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Diffstat (limited to 'include/event2')
25 files changed, 9592 insertions, 0 deletions
diff --git a/include/event2/buffer.h b/include/event2/buffer.h new file mode 100644 index 000000000000..468588b9f141 --- /dev/null +++ b/include/event2/buffer.h @@ -0,0 +1,1076 @@ +/* + * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#ifndef EVENT2_BUFFER_H_INCLUDED_ +#define EVENT2_BUFFER_H_INCLUDED_ + +/** @file event2/buffer.h + + Functions for buffering data for network sending or receiving. + + An evbuffer can be used for preparing data before sending it to + the network or conversely for reading data from the network. + Evbuffers try to avoid memory copies as much as possible. As a + result, evbuffers can be used to pass data around without actually + incurring the overhead of copying the data. + + A new evbuffer can be allocated with evbuffer_new(), and can be + freed with evbuffer_free(). Most users will be using evbuffers via + the bufferevent interface. To access a bufferevent's evbuffers, use + bufferevent_get_input() and bufferevent_get_output(). + + There are several guidelines for using evbuffers. + + - if you already know how much data you are going to add as a result + of calling evbuffer_add() multiple times, it makes sense to use + evbuffer_expand() first to make sure that enough memory is allocated + before hand. + + - evbuffer_add_buffer() adds the contents of one buffer to the other + without incurring any unnecessary memory copies. + + - evbuffer_add() and evbuffer_add_buffer() do not mix very well: + if you use them, you will wind up with fragmented memory in your + buffer. + + - For high-performance code, you may want to avoid copying data into and out + of buffers. You can skip the copy step by using + evbuffer_reserve_space()/evbuffer_commit_space() when writing into a + buffer, and evbuffer_peek() when reading. + + In Libevent 2.0 and later, evbuffers are represented using a linked + list of memory chunks, with pointers to the first and last chunk in + the chain. + + As the contents of an evbuffer can be stored in multiple different + memory blocks, it cannot be accessed directly. Instead, evbuffer_pullup() + can be used to force a specified number of bytes to be contiguous. This + will cause memory reallocation and memory copies if the data is split + across multiple blocks. It is more efficient, however, to use + evbuffer_peek() if you don't require that the memory to be contiguous. + */ + +#include <event2/visibility.h> + +#ifdef __cplusplus +extern "C" { +#endif + +#include <event2/event-config.h> +#include <stdarg.h> +#ifdef EVENT__HAVE_SYS_TYPES_H +#include <sys/types.h> +#endif +#ifdef EVENT__HAVE_SYS_UIO_H +#include <sys/uio.h> +#endif +#include <event2/util.h> + +/** + An evbuffer is an opaque data type for efficiently buffering data to be + sent or received on the network. + + @see event2/event.h for more information +*/ +struct evbuffer +#ifdef EVENT_IN_DOXYGEN_ +{} +#endif +; + +/** + Pointer to a position within an evbuffer. + + Used when repeatedly searching through a buffer. Calling any function + that modifies or re-packs the buffer contents may invalidate all + evbuffer_ptrs for that buffer. Do not modify or contruct these values + except with evbuffer_ptr_set. + + An evbuffer_ptr can represent any position from the start of a buffer up + to a position immediately after the end of a buffer. + + @see evbuffer_ptr_set() + */ +struct evbuffer_ptr { + ev_ssize_t pos; + + /* Do not alter or rely on the values of fields: they are for internal + * use */ + struct { + void *chain; + size_t pos_in_chain; + } internal_; +}; + +/** Describes a single extent of memory inside an evbuffer. Used for + direct-access functions. + + @see evbuffer_reserve_space, evbuffer_commit_space, evbuffer_peek + */ +#ifdef EVENT__HAVE_SYS_UIO_H +#define evbuffer_iovec iovec +/* Internal use -- defined only if we are using the native struct iovec */ +#define EVBUFFER_IOVEC_IS_NATIVE_ +#else +struct evbuffer_iovec { + /** The start of the extent of memory. */ + void *iov_base; + /** The length of the extent of memory. */ + size_t iov_len; +}; +#endif + +/** + Allocate storage for a new evbuffer. + + @return a pointer to a newly allocated evbuffer struct, or NULL if an error + occurred + */ +EVENT2_EXPORT_SYMBOL +struct evbuffer *evbuffer_new(void); +/** + Deallocate storage for an evbuffer. + + @param buf pointer to the evbuffer to be freed + */ +EVENT2_EXPORT_SYMBOL +void evbuffer_free(struct evbuffer *buf); + +/** + Enable locking on an evbuffer so that it can safely be used by multiple + threads at the same time. + + NOTE: when locking is enabled, the lock will be held when callbacks are + invoked. This could result in deadlock if you aren't careful. Plan + accordingly! + + @param buf An evbuffer to make lockable. + @param lock A lock object, or NULL if we should allocate our own. + @return 0 on success, -1 on failure. + */ +EVENT2_EXPORT_SYMBOL +int evbuffer_enable_locking(struct evbuffer *buf, void *lock); + +/** + Acquire the lock on an evbuffer. Has no effect if locking was not enabled + with evbuffer_enable_locking. +*/ +EVENT2_EXPORT_SYMBOL +void evbuffer_lock(struct evbuffer *buf); + +/** + Release the lock on an evbuffer. Has no effect if locking was not enabled + with evbuffer_enable_locking. +*/ +EVENT2_EXPORT_SYMBOL +void evbuffer_unlock(struct evbuffer *buf); + + +/** If this flag is set, then we will not use evbuffer_peek(), + * evbuffer_remove(), evbuffer_remove_buffer(), and so on to read bytes + * from this buffer: we'll only take bytes out of this buffer by + * writing them to the network (as with evbuffer_write_atmost), by + * removing them without observing them (as with evbuffer_drain), + * or by copying them all out at once (as with evbuffer_add_buffer). + * + * Using this option allows the implementation to use sendfile-based + * operations for evbuffer_add_file(); see that function for more + * information. + * + * This flag is on by default for bufferevents that can take advantage + * of it; you should never actually need to set it on a bufferevent's + * output buffer. + */ +#define EVBUFFER_FLAG_DRAINS_TO_FD 1 + +/** Change the flags that are set for an evbuffer by adding more. + * + * @param buffer the evbuffer that the callback is watching. + * @param cb the callback whose status we want to change. + * @param flags One or more EVBUFFER_FLAG_* options + * @return 0 on success, -1 on failure. + */ +EVENT2_EXPORT_SYMBOL +int evbuffer_set_flags(struct evbuffer *buf, ev_uint64_t flags); +/** Change the flags that are set for an evbuffer by removing some. + * + * @param buffer the evbuffer that the callback is watching. + * @param cb the callback whose status we want to change. + * @param flags One or more EVBUFFER_FLAG_* options + * @return 0 on success, -1 on failure. + */ +EVENT2_EXPORT_SYMBOL +int evbuffer_clear_flags(struct evbuffer *buf, ev_uint64_t flags); + +/** + Returns the total number of bytes stored in the evbuffer + + @param buf pointer to the evbuffer + @return the number of bytes stored in the evbuffer +*/ +EVENT2_EXPORT_SYMBOL +size_t evbuffer_get_length(const struct evbuffer *buf); + +/** + Returns the number of contiguous available bytes in the first buffer chain. + + This is useful when processing data that might be split into multiple + chains, or that might all be in the first chain. Calls to + evbuffer_pullup() that cause reallocation and copying of data can thus be + avoided. + + @param buf pointer to the evbuffer + @return 0 if no data is available, otherwise the number of available bytes + in the first buffer chain. +*/ +EVENT2_EXPORT_SYMBOL +size_t evbuffer_get_contiguous_space(const struct evbuffer *buf); + +/** + Expands the available space in an evbuffer. + + Expands the available space in the evbuffer to at least datlen, so that + appending datlen additional bytes will not require any new allocations. + + @param buf the evbuffer to be expanded + @param datlen the new minimum length requirement + @return 0 if successful, or -1 if an error occurred +*/ +EVENT2_EXPORT_SYMBOL +int evbuffer_expand(struct evbuffer *buf, size_t datlen); + +/** + Reserves space in the last chain or chains of an evbuffer. + + Makes space available in the last chain or chains of an evbuffer that can + be arbitrarily written to by a user. The space does not become + available for reading until it has been committed with + evbuffer_commit_space(). + + The space is made available as one or more extents, represented by + an initial pointer and a length. You can force the memory to be + available as only one extent. Allowing more extents, however, makes the + function more efficient. + + Multiple subsequent calls to this function will make the same space + available until evbuffer_commit_space() has been called. + + It is an error to do anything that moves around the buffer's internal + memory structures before committing the space. + + NOTE: The code currently does not ever use more than two extents. + This may change in future versions. + + @param buf the evbuffer in which to reserve space. + @param size how much space to make available, at minimum. The + total length of the extents may be greater than the requested + length. + @param vec an array of one or more evbuffer_iovec structures to + hold pointers to the reserved extents of memory. + @param n_vec The length of the vec array. Must be at least 1; + 2 is more efficient. + @return the number of provided extents, or -1 on error. + @see evbuffer_commit_space() +*/ +EVENT2_EXPORT_SYMBOL +int +evbuffer_reserve_space(struct evbuffer *buf, ev_ssize_t size, + struct evbuffer_iovec *vec, int n_vec); + +/** + Commits previously reserved space. + + Commits some of the space previously reserved with + evbuffer_reserve_space(). It then becomes available for reading. + + This function may return an error if the pointer in the extents do + not match those returned from evbuffer_reserve_space, or if data + has been added to the buffer since the space was reserved. + + If you want to commit less data than you got reserved space for, + modify the iov_len pointer of the appropriate extent to a smaller + value. Note that you may have received more space than you + requested if it was available! + + @param buf the evbuffer in which to reserve space. + @param vec one or two extents returned by evbuffer_reserve_space. + @param n_vecs the number of extents. + @return 0 on success, -1 on error + @see evbuffer_reserve_space() +*/ +EVENT2_EXPORT_SYMBOL +int evbuffer_commit_space(struct evbuffer *buf, + struct evbuffer_iovec *vec, int n_vecs); + +/** + Append data to the end of an evbuffer. + + @param buf the evbuffer to be appended to + @param data pointer to the beginning of the data buffer + @param datlen the number of bytes to be copied from the data buffer + @return 0 on success, -1 on failure. + */ +EVENT2_EXPORT_SYMBOL +int evbuffer_add(struct evbuffer *buf, const void *data, size_t datlen); + + +/** + Read data from an evbuffer and drain the bytes read. + + If more bytes are requested than are available in the evbuffer, we + only extract as many bytes as were available. + + @param buf the evbuffer to be read from + @param data the destination buffer to store the result + @param datlen the maximum size of the destination buffer + @return the number of bytes read, or -1 if we can't drain the buffer. + */ +EVENT2_EXPORT_SYMBOL +int evbuffer_remove(struct evbuffer *buf, void *data, size_t datlen); + +/** + Read data from an evbuffer, and leave the buffer unchanged. + + If more bytes are requested than are available in the evbuffer, we + only extract as many bytes as were available. + + @param buf the evbuffer to be read from + @param data_out the destination buffer to store the result + @param datlen the maximum size of the destination buffer + @return the number of bytes read, or -1 if we can't drain the buffer. + */ +EVENT2_EXPORT_SYMBOL +ev_ssize_t evbuffer_copyout(struct evbuffer *buf, void *data_out, size_t datlen); + +/** + Read data from the middle of an evbuffer, and leave the buffer unchanged. + + If more bytes are requested than are available in the evbuffer, we + only extract as many bytes as were available. + + @param buf the evbuffer to be read from + @param pos the position to start reading from + @param data_out the destination buffer to store the result + @param datlen the maximum size of the destination buffer + @return the number of bytes read, or -1 if we can't drain the buffer. + */ +EVENT2_EXPORT_SYMBOL +ev_ssize_t evbuffer_copyout_from(struct evbuffer *buf, const struct evbuffer_ptr *pos, void *data_out, size_t datlen); + +/** + Read data from an evbuffer into another evbuffer, draining + the bytes from the source buffer. This function avoids copy + operations to the extent possible. + + If more bytes are requested than are available in src, the src + buffer is drained completely. + + @param src the evbuffer to be read from + @param dst the destination evbuffer to store the result into + @param datlen the maximum numbers of bytes to transfer + @return the number of bytes read + */ +EVENT2_EXPORT_SYMBOL +int evbuffer_remove_buffer(struct evbuffer *src, struct evbuffer *dst, + size_t datlen); + +/** Used to tell evbuffer_readln what kind of line-ending to look for. + */ +enum evbuffer_eol_style { + /** Any sequence of CR and LF characters is acceptable as an + * EOL. + * + * Note that this style can produce ambiguous results: the + * sequence "CRLF" will be treated as a single EOL if it is + * all in the buffer at once, but if you first read a CR from + * the network and later read an LF from the network, it will + * be treated as two EOLs. + */ + EVBUFFER_EOL_ANY, + /** An EOL is an LF, optionally preceded by a CR. This style is + * most useful for implementing text-based internet protocols. */ + EVBUFFER_EOL_CRLF, + /** An EOL is a CR followed by an LF. */ + EVBUFFER_EOL_CRLF_STRICT, + /** An EOL is a LF. */ + EVBUFFER_EOL_LF, + /** An EOL is a NUL character (that is, a single byte with value 0) */ + EVBUFFER_EOL_NUL +}; + +/** + * Read a single line from an evbuffer. + * + * Reads a line terminated by an EOL as determined by the evbuffer_eol_style + * argument. Returns a newly allocated nul-terminated string; the caller must + * free the returned value. The EOL is not included in the returned string. + * + * @param buffer the evbuffer to read from + * @param n_read_out if non-NULL, points to a size_t that is set to the + * number of characters in the returned string. This is useful for + * strings that can contain NUL characters. + * @param eol_style the style of line-ending to use. + * @return pointer to a single line, or NULL if an error occurred + */ +EVENT2_EXPORT_SYMBOL +char *evbuffer_readln(struct evbuffer *buffer, size_t *n_read_out, + enum evbuffer_eol_style eol_style); + +/** + Move all data from one evbuffer into another evbuffer. + + This is a destructive add. The data from one buffer moves into + the other buffer. However, no unnecessary memory copies occur. + + @param outbuf the output buffer + @param inbuf the input buffer + @return 0 if successful, or -1 if an error occurred + + @see evbuffer_remove_buffer() + */ +EVENT2_EXPORT_SYMBOL +int evbuffer_add_buffer(struct evbuffer *outbuf, struct evbuffer *inbuf); + +/** + Copy data from one evbuffer into another evbuffer. + + This is a non-destructive add. The data from one buffer is copied + into the other buffer. However, no unnecessary memory copies occur. + + Note that buffers already containing buffer references can't be added + to other buffers. + + @param outbuf the output buffer + @param inbuf the input buffer + @return 0 if successful, or -1 if an error occurred + */ +EVENT2_EXPORT_SYMBOL +int evbuffer_add_buffer_reference(struct evbuffer *outbuf, + struct evbuffer *inbuf); + +/** + A cleanup function for a piece of memory added to an evbuffer by + reference. + + @see evbuffer_add_reference() + */ +typedef void (*evbuffer_ref_cleanup_cb)(const void *data, + size_t datalen, void *extra); + +/** + Reference memory into an evbuffer without copying. + + The memory needs to remain valid until all the added data has been + read. This function keeps just a reference to the memory without + actually incurring the overhead of a copy. + + @param outbuf the output buffer + @param data the memory to reference + @param datlen how memory to reference + @param cleanupfn callback to be invoked when the memory is no longer + referenced by this evbuffer. + @param cleanupfn_arg optional argument to the cleanup callback + @return 0 if successful, or -1 if an error occurred + */ +EVENT2_EXPORT_SYMBOL +int evbuffer_add_reference(struct evbuffer *outbuf, + const void *data, size_t datlen, + evbuffer_ref_cleanup_cb cleanupfn, void *cleanupfn_arg); + +/** + Copy data from a file into the evbuffer for writing to a socket. + + This function avoids unnecessary data copies between userland and + kernel. If sendfile is available and the EVBUFFER_FLAG_DRAINS_TO_FD + flag is set, it uses those functions. Otherwise, it tries to use + mmap (or CreateFileMapping on Windows). + + The function owns the resulting file descriptor and will close it + when finished transferring data. + + The results of using evbuffer_remove() or evbuffer_pullup() on + evbuffers whose data was added using this function are undefined. + + For more fine-grained control, use evbuffer_add_file_segment. + + @param outbuf the output buffer + @param fd the file descriptor + @param offset the offset from which to read data + @param length how much data to read, or -1 to read as much as possible. + (-1 requires that 'fd' support fstat.) + @return 0 if successful, or -1 if an error occurred +*/ + +EVENT2_EXPORT_SYMBOL +int evbuffer_add_file(struct evbuffer *outbuf, int fd, ev_off_t offset, + ev_off_t length); + +/** + An evbuffer_file_segment holds a reference to a range of a file -- + possibly the whole file! -- for use in writing from an evbuffer to a + socket. It could be implemented with mmap, sendfile, splice, or (if all + else fails) by just pulling all the data into RAM. A single + evbuffer_file_segment can be added more than once, and to more than one + evbuffer. + */ +struct evbuffer_file_segment; + +/** + Flag for creating evbuffer_file_segment: If this flag is set, then when + the evbuffer_file_segment is freed and no longer in use by any + evbuffer, the underlying fd is closed. + */ +#define EVBUF_FS_CLOSE_ON_FREE 0x01 +/** + Flag for creating evbuffer_file_segment: Disable memory-map based + implementations. + */ +#define EVBUF_FS_DISABLE_MMAP 0x02 +/** + Flag for creating evbuffer_file_segment: Disable direct fd-to-fd + implementations (including sendfile and splice). + + You might want to use this option if data needs to be taken from the + evbuffer by any means other than writing it to the network: the sendfile + backend is fast, but it only works for sending files directly to the + network. + */ +#define EVBUF_FS_DISABLE_SENDFILE 0x04 +/** + Flag for creating evbuffer_file_segment: Do not allocate a lock for this + segment. If this option is set, then neither the segment nor any + evbuffer it is added to may ever be accessed from more than one thread + at a time. + */ +#define EVBUF_FS_DISABLE_LOCKING 0x08 + +/** + A cleanup function for a evbuffer_file_segment added to an evbuffer + for reference. + */ +typedef void (*evbuffer_file_segment_cleanup_cb)( + struct evbuffer_file_segment const* seg, int flags, void* arg); + +/** + Create and return a new evbuffer_file_segment for reading data from a + file and sending it out via an evbuffer. + + This function avoids unnecessary data copies between userland and + kernel. Where available, it uses sendfile or splice. + + The file descriptor must not be closed so long as any evbuffer is using + this segment. + + The results of using evbuffer_remove() or evbuffer_pullup() or any other + function that reads bytes from an evbuffer on any evbuffer containing + the newly returned segment are undefined, unless you pass the + EVBUF_FS_DISABLE_SENDFILE flag to this function. + + @param fd an open file to read from. + @param offset an index within the file at which to start reading + @param length how much data to read, or -1 to read as much as possible. + (-1 requires that 'fd' support fstat.) + @param flags any number of the EVBUF_FS_* flags + @return a new evbuffer_file_segment, or NULL on failure. + **/ +EVENT2_EXPORT_SYMBOL +struct evbuffer_file_segment *evbuffer_file_segment_new( + int fd, ev_off_t offset, ev_off_t length, unsigned flags); + +/** + Free an evbuffer_file_segment + + It is safe to call this function even if the segment has been added to + one or more evbuffers. The evbuffer_file_segment will not be freed + until no more references to it exist. + */ +EVENT2_EXPORT_SYMBOL +void evbuffer_file_segment_free(struct evbuffer_file_segment *seg); + +/** + Add cleanup callback and argument for the callback to an + evbuffer_file_segment. + + The cleanup callback will be invoked when no more references to the + evbuffer_file_segment exist. + **/ +EVENT2_EXPORT_SYMBOL +void evbuffer_file_segment_add_cleanup_cb(struct evbuffer_file_segment *seg, + evbuffer_file_segment_cleanup_cb cb, void* arg); + +/** + Insert some or all of an evbuffer_file_segment at the end of an evbuffer + + Note that the offset and length parameters of this function have a + different meaning from those provided to evbuffer_file_segment_new: When + you create the segment, the offset is the offset _within the file_, and + the length is the length _of the segment_, whereas when you add a + segment to an evbuffer, the offset is _within the segment_ and the + length is the length of the _part of the segment you want to use. + + In other words, if you have a 10 KiB file, and you create an + evbuffer_file_segment for it with offset 20 and length 1000, it will + refer to bytes 20..1019 inclusive. If you then pass this segment to + evbuffer_add_file_segment and specify an offset of 20 and a length of + 50, you will be adding bytes 40..99 inclusive. + + @param buf the evbuffer to append to + @param seg the segment to add + @param offset the offset within the segment to start from + @param length the amount of data to add, or -1 to add it all. + @return 0 on success, -1 on failure. + */ +EVENT2_EXPORT_SYMBOL +int evbuffer_add_file_segment(struct evbuffer *buf, + struct evbuffer_file_segment *seg, ev_off_t offset, ev_off_t length); + +/** + Append a formatted string to the end of an evbuffer. + + The string is formated as printf. + + @param buf the evbuffer that will be appended to + @param fmt a format string + @param ... arguments that will be passed to printf(3) + @return The number of bytes added if successful, or -1 if an error occurred. + + @see evutil_printf(), evbuffer_add_vprintf() + */ +EVENT2_EXPORT_SYMBOL +int evbuffer_add_printf(struct evbuffer *buf, const char *fmt, ...) +#ifdef __GNUC__ + __attribute__((format(printf, 2, 3))) +#endif +; + +/** + Append a va_list formatted string to the end of an evbuffer. + + @param buf the evbuffer that will be appended to + @param fmt a format string + @param ap a varargs va_list argument array that will be passed to vprintf(3) + @return The number of bytes added if successful, or -1 if an error occurred. + */ +EVENT2_EXPORT_SYMBOL +int evbuffer_add_vprintf(struct evbuffer *buf, const char *fmt, va_list ap) +#ifdef __GNUC__ + __attribute__((format(printf, 2, 0))) +#endif +; + + +/** + Remove a specified number of bytes data from the beginning of an evbuffer. + + @param buf the evbuffer to be drained + @param len the number of bytes to drain from the beginning of the buffer + @return 0 on success, -1 on failure. + */ +EVENT2_EXPORT_SYMBOL +int evbuffer_drain(struct evbuffer *buf, size_t len); + + +/** + Write the contents of an evbuffer to a file descriptor. + + The evbuffer will be drained after the bytes have been successfully written. + + @param buffer the evbuffer to be written and drained + @param fd the file descriptor to be written to + @return the number of bytes written, or -1 if an error occurred + @see evbuffer_read() + */ +EVENT2_EXPORT_SYMBOL +int evbuffer_write(struct evbuffer *buffer, evutil_socket_t fd); + +/** + Write some of the contents of an evbuffer to a file descriptor. + + The evbuffer will be drained after the bytes have been successfully written. + + @param buffer the evbuffer to be written and drained + @param fd the file descriptor to be written to + @param howmuch the largest allowable number of bytes to write, or -1 + to write as many bytes as we can. + @return the number of bytes written, or -1 if an error occurred + @see evbuffer_read() + */ +EVENT2_EXPORT_SYMBOL +int evbuffer_write_atmost(struct evbuffer *buffer, evutil_socket_t fd, + ev_ssize_t howmuch); + +/** + Read from a file descriptor and store the result in an evbuffer. + + @param buffer the evbuffer to store the result + @param fd the file descriptor to read from + @param howmuch the number of bytes to be read + @return the number of bytes read, or -1 if an error occurred + @see evbuffer_write() + */ +EVENT2_EXPORT_SYMBOL +int evbuffer_read(struct evbuffer *buffer, evutil_socket_t fd, int howmuch); + +/** + Search for a string within an evbuffer. + + @param buffer the evbuffer to be searched + @param what the string to be searched for + @param len the length of the search string + @param start NULL or a pointer to a valid struct evbuffer_ptr. + @return a struct evbuffer_ptr whose 'pos' field has the offset of the + first occurrence of the string in the buffer after 'start'. The 'pos' + field of the result is -1 if the string was not found. + */ +EVENT2_EXPORT_SYMBOL +struct evbuffer_ptr evbuffer_search(struct evbuffer *buffer, const char *what, size_t len, const struct evbuffer_ptr *start); + +/** + Search for a string within part of an evbuffer. + + @param buffer the evbuffer to be searched + @param what the string to be searched for + @param len the length of the search string + @param start NULL or a pointer to a valid struct evbuffer_ptr that + indicates where we should start searching. + @param end NULL or a pointer to a valid struct evbuffer_ptr that + indicates where we should stop searching. + @return a struct evbuffer_ptr whose 'pos' field has the offset of the + first occurrence of the string in the buffer after 'start'. The 'pos' + field of the result is -1 if the string was not found. + */ +EVENT2_EXPORT_SYMBOL +struct evbuffer_ptr evbuffer_search_range(struct evbuffer *buffer, const char *what, size_t len, const struct evbuffer_ptr *start, const struct evbuffer_ptr *end); + +/** + Defines how to adjust an evbuffer_ptr by evbuffer_ptr_set() + + @see evbuffer_ptr_set() */ +enum evbuffer_ptr_how { + /** Sets the pointer to the position; can be called on with an + uninitialized evbuffer_ptr. */ + EVBUFFER_PTR_SET, + /** Advances the pointer by adding to the current position. */ + EVBUFFER_PTR_ADD +}; + +/** + Sets the search pointer in the buffer to position. + + There are two ways to use this function: you can call + evbuffer_ptr_set(buf, &pos, N, EVBUFFER_PTR_SET) + to move 'pos' to a position 'N' bytes after the start of the buffer, or + evbuffer_ptr_set(buf, &pos, N, EVBUFFER_PTR_ADD) + to move 'pos' forward by 'N' bytes. + + If evbuffer_ptr is not initialized, this function can only be called + with EVBUFFER_PTR_SET. + + An evbuffer_ptr can represent any position from the start of the buffer to + a position immediately after the end of the buffer. + + @param buffer the evbuffer to be search + @param ptr a pointer to a struct evbuffer_ptr + @param position the position at which to start the next search + @param how determines how the pointer should be manipulated. + @returns 0 on success or -1 otherwise +*/ +EVENT2_EXPORT_SYMBOL +int +evbuffer_ptr_set(struct evbuffer *buffer, struct evbuffer_ptr *ptr, + size_t position, enum evbuffer_ptr_how how); + +/** + Search for an end-of-line string within an evbuffer. + + @param buffer the evbuffer to be searched + @param start NULL or a pointer to a valid struct evbuffer_ptr to start + searching at. + @param eol_len_out If non-NULL, the pointed-to value will be set to + the length of the end-of-line string. + @param eol_style The kind of EOL to look for; see evbuffer_readln() for + more information + @return a struct evbuffer_ptr whose 'pos' field has the offset of the + first occurrence EOL in the buffer after 'start'. The 'pos' + field of the result is -1 if the string was not found. + */ +EVENT2_EXPORT_SYMBOL +struct evbuffer_ptr evbuffer_search_eol(struct evbuffer *buffer, + struct evbuffer_ptr *start, size_t *eol_len_out, + enum evbuffer_eol_style eol_style); + +/** Function to peek at data inside an evbuffer without removing it or + copying it out. + + Pointers to the data are returned by filling the 'vec_out' array + with pointers to one or more extents of data inside the buffer. + + The total data in the extents that you get back may be more than + you requested (if there is more data last extent than you asked + for), or less (if you do not provide enough evbuffer_iovecs, or if + the buffer does not have as much data as you asked to see). + + @param buffer the evbuffer to peek into, + @param len the number of bytes to try to peek. If len is negative, we + will try to fill as much of vec_out as we can. If len is negative + and vec_out is not provided, we return the number of evbuffer_iovecs + that would be needed to get all the data in the buffer. + @param start_at an evbuffer_ptr indicating the point at which we + should start looking for data. NULL means, "At the start of the + buffer." + @param vec_out an array of evbuffer_iovec + @param n_vec the length of vec_out. If 0, we only count how many + extents would be necessary to point to the requested amount of + data. + @return The number of extents needed. This may be less than n_vec + if we didn't need all the evbuffer_iovecs we were given, or more + than n_vec if we would need more to return all the data that was + requested. + */ +EVENT2_EXPORT_SYMBOL +int evbuffer_peek(struct evbuffer *buffer, ev_ssize_t len, + struct evbuffer_ptr *start_at, + struct evbuffer_iovec *vec_out, int n_vec); + + +/** Structure passed to an evbuffer_cb_func evbuffer callback + + @see evbuffer_cb_func, evbuffer_add_cb() + */ +struct evbuffer_cb_info { + /** The number of bytes in this evbuffer when callbacks were last + * invoked. */ + size_t orig_size; + /** The number of bytes added since callbacks were last invoked. */ + size_t n_added; + /** The number of bytes removed since callbacks were last invoked. */ + size_t n_deleted; +}; + +/** Type definition for a callback that is invoked whenever data is added or + removed from an evbuffer. + + An evbuffer may have one or more callbacks set at a time. The order + in which they are executed is undefined. + + A callback function may add more callbacks, or remove itself from the + list of callbacks, or add or remove data from the buffer. It may not + remove another callback from the list. + + If a callback adds or removes data from the buffer or from another + buffer, this can cause a recursive invocation of your callback or + other callbacks. If you ask for an infinite loop, you might just get + one: watch out! + + @param buffer the buffer whose size has changed + @param info a structure describing how the buffer changed. + @param arg a pointer to user data +*/ +typedef void (*evbuffer_cb_func)(struct evbuffer *buffer, const struct evbuffer_cb_info *info, void *arg); + +struct evbuffer_cb_entry; +/** Add a new callback to an evbuffer. + + Subsequent calls to evbuffer_add_cb() add new callbacks. To remove this + callback, call evbuffer_remove_cb or evbuffer_remove_cb_entry. + + @param buffer the evbuffer to be monitored + @param cb the callback function to invoke when the evbuffer is modified, + or NULL to remove all callbacks. + @param cbarg an argument to be provided to the callback function + @return a handle to the callback on success, or NULL on failure. + */ +EVENT2_EXPORT_SYMBOL +struct evbuffer_cb_entry *evbuffer_add_cb(struct evbuffer *buffer, evbuffer_cb_func cb, void *cbarg); + +/** Remove a callback from an evbuffer, given a handle returned from + evbuffer_add_cb. + + Calling this function invalidates the handle. + + @return 0 if a callback was removed, or -1 if no matching callback was + found. + */ +EVENT2_EXPORT_SYMBOL +int evbuffer_remove_cb_entry(struct evbuffer *buffer, + struct evbuffer_cb_entry *ent); + +/** Remove a callback from an evbuffer, given the function and argument + used to add it. + + @return 0 if a callback was removed, or -1 if no matching callback was + found. + */ +EVENT2_EXPORT_SYMBOL +int evbuffer_remove_cb(struct evbuffer *buffer, evbuffer_cb_func cb, void *cbarg); + +/** If this flag is not set, then a callback is temporarily disabled, and + * should not be invoked. + * + * @see evbuffer_cb_set_flags(), evbuffer_cb_clear_flags() + */ +#define EVBUFFER_CB_ENABLED 1 + +/** Change the flags that are set for a callback on a buffer by adding more. + + @param buffer the evbuffer that the callback is watching. + @param cb the callback whose status we want to change. + @param flags EVBUFFER_CB_ENABLED to re-enable the callback. + @return 0 on success, -1 on failure. + */ +EVENT2_EXPORT_SYMBOL +int evbuffer_cb_set_flags(struct evbuffer *buffer, + struct evbuffer_cb_entry *cb, ev_uint32_t flags); + +/** Change the flags that are set for a callback on a buffer by removing some + + @param buffer the evbuffer that the callback is watching. + @param cb the callback whose status we want to change. + @param flags EVBUFFER_CB_ENABLED to disable the callback. + @return 0 on success, -1 on failure. + */ +EVENT2_EXPORT_SYMBOL +int evbuffer_cb_clear_flags(struct evbuffer *buffer, + struct evbuffer_cb_entry *cb, ev_uint32_t flags); + +#if 0 +/** Postpone calling a given callback until unsuspend is called later. + + This is different from disabling the callback, since the callback will get + invoked later if the buffer size changes between now and when we unsuspend + it. + + @param the buffer that the callback is watching. + @param cb the callback we want to suspend. + */ +EVENT2_EXPORT_SYMBOL +void evbuffer_cb_suspend(struct evbuffer *buffer, struct evbuffer_cb_entry *cb); +/** Stop postponing a callback that we postponed with evbuffer_cb_suspend. + + If data was added to or removed from the buffer while the callback was + suspended, the callback will get called once now. + + @param the buffer that the callback is watching. + @param cb the callback we want to stop suspending. + */ +EVENT2_EXPORT_SYMBOL +void evbuffer_cb_unsuspend(struct evbuffer *buffer, struct evbuffer_cb_entry *cb); +#endif + +/** + Makes the data at the beginning of an evbuffer contiguous. + + @param buf the evbuffer to make contiguous + @param size the number of bytes to make contiguous, or -1 to make the + entire buffer contiguous. + @return a pointer to the contiguous memory array, or NULL if param size + requested more data than is present in the buffer. +*/ + +EVENT2_EXPORT_SYMBOL +unsigned char *evbuffer_pullup(struct evbuffer *buf, ev_ssize_t size); + +/** + Prepends data to the beginning of the evbuffer + + @param buf the evbuffer to which to prepend data + @param data a pointer to the memory to prepend + @param size the number of bytes to prepend + @return 0 if successful, or -1 otherwise +*/ + +EVENT2_EXPORT_SYMBOL +int evbuffer_prepend(struct evbuffer *buf, const void *data, size_t size); + +/** + Prepends all data from the src evbuffer to the beginning of the dst + evbuffer. + + @param dst the evbuffer to which to prepend data + @param src the evbuffer to prepend; it will be emptied as a result + @return 0 if successful, or -1 otherwise +*/ +EVENT2_EXPORT_SYMBOL +int evbuffer_prepend_buffer(struct evbuffer *dst, struct evbuffer* src); + +/** + Prevent calls that modify an evbuffer from succeeding. A buffer may + frozen at the front, at the back, or at both the front and the back. + + If the front of a buffer is frozen, operations that drain data from + the front of the buffer, or that prepend data to the buffer, will + fail until it is unfrozen. If the back a buffer is frozen, operations + that append data from the buffer will fail until it is unfrozen. + + @param buf The buffer to freeze + @param at_front If true, we freeze the front of the buffer. If false, + we freeze the back. + @return 0 on success, -1 on failure. +*/ +EVENT2_EXPORT_SYMBOL +int evbuffer_freeze(struct evbuffer *buf, int at_front); +/** + Re-enable calls that modify an evbuffer. + + @param buf The buffer to un-freeze + @param at_front If true, we unfreeze the front of the buffer. If false, + we unfreeze the back. + @return 0 on success, -1 on failure. + */ +EVENT2_EXPORT_SYMBOL +int evbuffer_unfreeze(struct evbuffer *buf, int at_front); + +struct event_base; +/** + Force all the callbacks on an evbuffer to be run, not immediately after + the evbuffer is altered, but instead from inside the event loop. + + This can be used to serialize all the callbacks to a single thread + of execution. + */ +EVENT2_EXPORT_SYMBOL +int evbuffer_defer_callbacks(struct evbuffer *buffer, struct event_base *base); + +/** + Append data from 1 or more iovec's to an evbuffer + + Calculates the number of bytes needed for an iovec structure and guarantees + all data will fit into a single chain. Can be used in lieu of functionality + which calls evbuffer_add() constantly before being used to increase + performance. + + @param buffer the destination buffer + @param vec the source iovec + @param n_vec the number of iovec structures. + @return the number of bytes successfully written to the output buffer. +*/ +EVENT2_EXPORT_SYMBOL +size_t evbuffer_add_iovec(struct evbuffer * buffer, struct evbuffer_iovec * vec, int n_vec); + +#ifdef __cplusplus +} +#endif + +#endif /* EVENT2_BUFFER_H_INCLUDED_ */ diff --git a/include/event2/buffer_compat.h b/include/event2/buffer_compat.h new file mode 100644 index 000000000000..24f828c21033 --- /dev/null +++ b/include/event2/buffer_compat.h @@ -0,0 +1,115 @@ +/* + * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#ifndef EVENT2_BUFFER_COMPAT_H_INCLUDED_ +#define EVENT2_BUFFER_COMPAT_H_INCLUDED_ + +#include <event2/visibility.h> + +/** @file event2/buffer_compat.h + + Obsolete and deprecated versions of the functions in buffer.h: provided + only for backward compatibility. + */ + + +/** + Obsolete alias for evbuffer_readln(buffer, NULL, EVBUFFER_EOL_ANY). + + @deprecated This function is deprecated because its behavior is not correct + for almost any protocol, and also because it's wholly subsumed by + evbuffer_readln(). + + @param buffer the evbuffer to read from + @return pointer to a single line, or NULL if an error occurred + +*/ +EVENT2_EXPORT_SYMBOL +char *evbuffer_readline(struct evbuffer *buffer); + +/** Type definition for a callback that is invoked whenever data is added or + removed from an evbuffer. + + An evbuffer may have one or more callbacks set at a time. The order + in which they are executed is undefined. + + A callback function may add more callbacks, or remove itself from the + list of callbacks, or add or remove data from the buffer. It may not + remove another callback from the list. + + If a callback adds or removes data from the buffer or from another + buffer, this can cause a recursive invocation of your callback or + other callbacks. If you ask for an infinite loop, you might just get + one: watch out! + + @param buffer the buffer whose size has changed + @param old_len the previous length of the buffer + @param new_len the current length of the buffer + @param arg a pointer to user data +*/ +typedef void (*evbuffer_cb)(struct evbuffer *buffer, size_t old_len, size_t new_len, void *arg); + +/** + Replace all callbacks on an evbuffer with a single new callback, or + remove them. + + Subsequent calls to evbuffer_setcb() replace callbacks set by previous + calls. Setting the callback to NULL removes any previously set callback. + + @deprecated This function is deprecated because it clears all previous + callbacks set on the evbuffer, which can cause confusing behavior if + multiple parts of the code all want to add their own callbacks on a + buffer. Instead, use evbuffer_add(), evbuffer_del(), and + evbuffer_setflags() to manage your own evbuffer callbacks without + interfering with callbacks set by others. + + @param buffer the evbuffer to be monitored + @param cb the callback function to invoke when the evbuffer is modified, + or NULL to remove all callbacks. + @param cbarg an argument to be provided to the callback function + */ +EVENT2_EXPORT_SYMBOL +void evbuffer_setcb(struct evbuffer *buffer, evbuffer_cb cb, void *cbarg); + + +/** + Find a string within an evbuffer. + + @param buffer the evbuffer to be searched + @param what the string to be searched for + @param len the length of the search string + @return a pointer to the beginning of the search string, or NULL if the search failed. + */ +EVENT2_EXPORT_SYMBOL +unsigned char *evbuffer_find(struct evbuffer *buffer, const unsigned char *what, size_t len); + +/** deprecated in favor of calling the functions directly */ +#define EVBUFFER_LENGTH(x) evbuffer_get_length(x) +/** deprecated in favor of calling the functions directly */ +#define EVBUFFER_DATA(x) evbuffer_pullup((x), -1) + +#endif + diff --git a/include/event2/bufferevent.h b/include/event2/bufferevent.h new file mode 100644 index 000000000000..825918e3a452 --- /dev/null +++ b/include/event2/bufferevent.h @@ -0,0 +1,1021 @@ +/* + * Copyright (c) 2000-2007 Niels Provos <provos@citi.umich.edu> + * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#ifndef EVENT2_BUFFEREVENT_H_INCLUDED_ +#define EVENT2_BUFFEREVENT_H_INCLUDED_ + +/** + @file event2/bufferevent.h + + Functions for buffering data for network sending or receiving. Bufferevents + are higher level than evbuffers: each has an underlying evbuffer for reading + and one for writing, and callbacks that are invoked under certain + circumstances. + + A bufferevent provides input and output buffers that get filled and + drained automatically. The user of a bufferevent no longer deals + directly with the I/O, but instead is reading from input and writing + to output buffers. + + Once initialized, the bufferevent structure can be used repeatedly + with bufferevent_enable() and bufferevent_disable(). + + When reading is enabled, the bufferevent will try to read from the + file descriptor onto its input buffer, and call the read callback. + When writing is enabled, the bufferevent will try to write data onto its + file descriptor when the output buffer has enough data, and call the write + callback when the output buffer is sufficiently drained. + + Bufferevents come in several flavors, including: + + <dl> + <dt>Socket-based bufferevents</dt> + <dd>A bufferevent that reads and writes data onto a network + socket. Created with bufferevent_socket_new().</dd> + + <dt>Paired bufferevents</dt> + <dd>A pair of bufferevents that send and receive data to one + another without touching the network. Created with + bufferevent_pair_new().</dd> + + <dt>Filtering bufferevents</dt> + <dd>A bufferevent that transforms data, and sends or receives it + over another underlying bufferevent. Created with + bufferevent_filter_new().</dd> + + <dt>SSL-backed bufferevents</dt> + <dd>A bufferevent that uses the openssl library to send and + receive data over an encrypted connection. Created with + bufferevent_openssl_socket_new() or + bufferevent_openssl_filter_new().</dd> + </dl> + */ + +#include <event2/visibility.h> + +#ifdef __cplusplus +extern "C" { +#endif + +#include <event2/event-config.h> +#ifdef EVENT__HAVE_SYS_TYPES_H +#include <sys/types.h> +#endif +#ifdef EVENT__HAVE_SYS_TIME_H +#include <sys/time.h> +#endif + +/* For int types. */ +#include <event2/util.h> + +/** @name Bufferevent event codes + + These flags are passed as arguments to a bufferevent's event callback. + + @{ +*/ +#define BEV_EVENT_READING 0x01 /**< error encountered while reading */ +#define BEV_EVENT_WRITING 0x02 /**< error encountered while writing */ +#define BEV_EVENT_EOF 0x10 /**< eof file reached */ +#define BEV_EVENT_ERROR 0x20 /**< unrecoverable error encountered */ +#define BEV_EVENT_TIMEOUT 0x40 /**< user-specified timeout reached */ +#define BEV_EVENT_CONNECTED 0x80 /**< connect operation finished. */ +/**@}*/ + +/** + An opaque type for handling buffered IO + + @see event2/bufferevent.h + */ +struct bufferevent +#ifdef EVENT_IN_DOXYGEN_ +{} +#endif +; +struct event_base; +struct evbuffer; +struct sockaddr; + +/** + A read or write callback for a bufferevent. + + The read callback is triggered when new data arrives in the input + buffer and the amount of readable data exceed the low watermark + which is 0 by default. + + The write callback is triggered if the write buffer has been + exhausted or fell below its low watermark. + + @param bev the bufferevent that triggered the callback + @param ctx the user-specified context for this bufferevent + */ +typedef void (*bufferevent_data_cb)(struct bufferevent *bev, void *ctx); + +/** + An event/error callback for a bufferevent. + + The event callback is triggered if either an EOF condition or another + unrecoverable error was encountered. + + For bufferevents with deferred callbacks, this is a bitwise OR of all errors + that have happened on the bufferevent since the last callback invocation. + + @param bev the bufferevent for which the error condition was reached + @param what a conjunction of flags: BEV_EVENT_READING or BEV_EVENT_WRITING + to indicate if the error was encountered on the read or write path, + and one of the following flags: BEV_EVENT_EOF, BEV_EVENT_ERROR, + BEV_EVENT_TIMEOUT, BEV_EVENT_CONNECTED. + + @param ctx the user-specified context for this bufferevent +*/ +typedef void (*bufferevent_event_cb)(struct bufferevent *bev, short what, void *ctx); + +/** Options that can be specified when creating a bufferevent */ +enum bufferevent_options { + /** If set, we close the underlying file + * descriptor/bufferevent/whatever when this bufferevent is freed. */ + BEV_OPT_CLOSE_ON_FREE = (1<<0), + + /** If set, and threading is enabled, operations on this bufferevent + * are protected by a lock */ + BEV_OPT_THREADSAFE = (1<<1), + + /** If set, callbacks are run deferred in the event loop. */ + BEV_OPT_DEFER_CALLBACKS = (1<<2), + + /** If set, callbacks are executed without locks being held on the + * bufferevent. This option currently requires that + * BEV_OPT_DEFER_CALLBACKS also be set; a future version of Libevent + * might remove the requirement.*/ + BEV_OPT_UNLOCK_CALLBACKS = (1<<3) +}; + +/** + Create a new socket bufferevent over an existing socket. + + @param base the event base to associate with the new bufferevent. + @param fd the file descriptor from which data is read and written to. + This file descriptor is not allowed to be a pipe(2). + It is safe to set the fd to -1, so long as you later + set it with bufferevent_setfd or bufferevent_socket_connect(). + @param options Zero or more BEV_OPT_* flags + @return a pointer to a newly allocated bufferevent struct, or NULL if an + error occurred + @see bufferevent_free() + */ +EVENT2_EXPORT_SYMBOL +struct bufferevent *bufferevent_socket_new(struct event_base *base, evutil_socket_t fd, int options); + +/** + Launch a connect() attempt with a socket-based bufferevent. + + When the connect succeeds, the eventcb will be invoked with + BEV_EVENT_CONNECTED set. + + If the bufferevent does not already have a socket set, we allocate a new + socket here and make it nonblocking before we begin. + + If no address is provided, we assume that the socket is already connecting, + and configure the bufferevent so that a BEV_EVENT_CONNECTED event will be + yielded when it is done connecting. + + @param bufev an existing bufferevent allocated with + bufferevent_socket_new(). + @param addr the address we should connect to + @param socklen The length of the address + @return 0 on success, -1 on failure. + */ +EVENT2_EXPORT_SYMBOL +int bufferevent_socket_connect(struct bufferevent *, const struct sockaddr *, int); + +struct evdns_base; +/** + Resolve the hostname 'hostname' and connect to it as with + bufferevent_socket_connect(). + + @param bufev An existing bufferevent allocated with bufferevent_socket_new() + @param evdns_base Optionally, an evdns_base to use for resolving hostnames + asynchronously. May be set to NULL for a blocking resolve. + @param family A preferred address family to resolve addresses to, or + AF_UNSPEC for no preference. Only AF_INET, AF_INET6, and AF_UNSPEC are + supported. + @param hostname The hostname to resolve; see below for notes on recognized + formats + @param port The port to connect to on the resolved address. + @return 0 if successful, -1 on failure. + + Recognized hostname formats are: + + www.example.com (hostname) + 1.2.3.4 (ipv4address) + ::1 (ipv6address) + [::1] ([ipv6address]) + + Performance note: If you do not provide an evdns_base, this function + may block while it waits for a DNS response. This is probably not + what you want. + */ +EVENT2_EXPORT_SYMBOL +int bufferevent_socket_connect_hostname(struct bufferevent *, + struct evdns_base *, int, const char *, int); + +/** + Return the error code for the last failed DNS lookup attempt made by + bufferevent_socket_connect_hostname(). + + @param bev The bufferevent object. + @return DNS error code. + @see evutil_gai_strerror() +*/ +EVENT2_EXPORT_SYMBOL +int bufferevent_socket_get_dns_error(struct bufferevent *bev); + +/** + Assign a bufferevent to a specific event_base. + + NOTE that only socket bufferevents support this function. + + @param base an event_base returned by event_init() + @param bufev a bufferevent struct returned by bufferevent_new() + or bufferevent_socket_new() + @return 0 if successful, or -1 if an error occurred + @see bufferevent_new() + */ +EVENT2_EXPORT_SYMBOL +int bufferevent_base_set(struct event_base *base, struct bufferevent *bufev); + +/** + Return the event_base used by a bufferevent +*/ +EVENT2_EXPORT_SYMBOL +struct event_base *bufferevent_get_base(struct bufferevent *bev); + +/** + Assign a priority to a bufferevent. + + Only supported for socket bufferevents. + + @param bufev a bufferevent struct + @param pri the priority to be assigned + @return 0 if successful, or -1 if an error occurred + */ +EVENT2_EXPORT_SYMBOL +int bufferevent_priority_set(struct bufferevent *bufev, int pri); + +/** + Return the priority of a bufferevent. + + Only supported for socket bufferevents + */ +EVENT2_EXPORT_SYMBOL +int bufferevent_get_priority(const struct bufferevent *bufev); + +/** + Deallocate the storage associated with a bufferevent structure. + + If there is pending data to write on the bufferevent, it probably won't be + flushed before the bufferevent is freed. + + @param bufev the bufferevent structure to be freed. + */ +EVENT2_EXPORT_SYMBOL +void bufferevent_free(struct bufferevent *bufev); + + +/** + Changes the callbacks for a bufferevent. + + @param bufev the bufferevent object for which to change callbacks + @param readcb callback to invoke when there is data to be read, or NULL if + no callback is desired + @param writecb callback to invoke when the file descriptor is ready for + writing, or NULL if no callback is desired + @param eventcb callback to invoke when there is an event on the file + descriptor + @param cbarg an argument that will be supplied to each of the callbacks + (readcb, writecb, and errorcb) + @see bufferevent_new() + */ +EVENT2_EXPORT_SYMBOL +void bufferevent_setcb(struct bufferevent *bufev, + bufferevent_data_cb readcb, bufferevent_data_cb writecb, + bufferevent_event_cb eventcb, void *cbarg); + +/** + Retrieves the callbacks for a bufferevent. + + @param bufev the bufferevent to examine. + @param readcb_ptr if readcb_ptr is nonnull, *readcb_ptr is set to the current + read callback for the bufferevent. + @param writecb_ptr if writecb_ptr is nonnull, *writecb_ptr is set to the + current write callback for the bufferevent. + @param eventcb_ptr if eventcb_ptr is nonnull, *eventcb_ptr is set to the + current event callback for the bufferevent. + @param cbarg_ptr if cbarg_ptr is nonnull, *cbarg_ptr is set to the current + callback argument for the bufferevent. + @see buffervent_setcb() +*/ +EVENT2_EXPORT_SYMBOL +void bufferevent_getcb(struct bufferevent *bufev, + bufferevent_data_cb *readcb_ptr, + bufferevent_data_cb *writecb_ptr, + bufferevent_event_cb *eventcb_ptr, + void **cbarg_ptr); + +/** + Changes the file descriptor on which the bufferevent operates. + Not supported for all bufferevent types. + + @param bufev the bufferevent object for which to change the file descriptor + @param fd the file descriptor to operate on +*/ +EVENT2_EXPORT_SYMBOL +int bufferevent_setfd(struct bufferevent *bufev, evutil_socket_t fd); + +/** + Returns the file descriptor associated with a bufferevent, or -1 if + no file descriptor is associated with the bufferevent. + */ +EVENT2_EXPORT_SYMBOL +evutil_socket_t bufferevent_getfd(struct bufferevent *bufev); + +/** + Returns the underlying bufferevent associated with a bufferevent (if + the bufferevent is a wrapper), or NULL if there is no underlying bufferevent. + */ +EVENT2_EXPORT_SYMBOL +struct bufferevent *bufferevent_get_underlying(struct bufferevent *bufev); + +/** + Write data to a bufferevent buffer. + + The bufferevent_write() function can be used to write data to the file + descriptor. The data is appended to the output buffer and written to the + descriptor automatically as it becomes available for writing. + + @param bufev the bufferevent to be written to + @param data a pointer to the data to be written + @param size the length of the data, in bytes + @return 0 if successful, or -1 if an error occurred + @see bufferevent_write_buffer() + */ +EVENT2_EXPORT_SYMBOL +int bufferevent_write(struct bufferevent *bufev, + const void *data, size_t size); + + +/** + Write data from an evbuffer to a bufferevent buffer. The evbuffer is + being drained as a result. + + @param bufev the bufferevent to be written to + @param buf the evbuffer to be written + @return 0 if successful, or -1 if an error occurred + @see bufferevent_write() + */ +EVENT2_EXPORT_SYMBOL +int bufferevent_write_buffer(struct bufferevent *bufev, struct evbuffer *buf); + + +/** + Read data from a bufferevent buffer. + + The bufferevent_read() function is used to read data from the input buffer. + + @param bufev the bufferevent to be read from + @param data pointer to a buffer that will store the data + @param size the size of the data buffer, in bytes + @return the amount of data read, in bytes. + */ +EVENT2_EXPORT_SYMBOL +size_t bufferevent_read(struct bufferevent *bufev, void *data, size_t size); + +/** + Read data from a bufferevent buffer into an evbuffer. This avoids + memory copies. + + @param bufev the bufferevent to be read from + @param buf the evbuffer to which to add data + @return 0 if successful, or -1 if an error occurred. + */ +EVENT2_EXPORT_SYMBOL +int bufferevent_read_buffer(struct bufferevent *bufev, struct evbuffer *buf); + +/** + Returns the input buffer. + + The user MUST NOT set the callback on this buffer. + + @param bufev the bufferevent from which to get the evbuffer + @return the evbuffer object for the input buffer + */ + +EVENT2_EXPORT_SYMBOL +struct evbuffer *bufferevent_get_input(struct bufferevent *bufev); + +/** + Returns the output buffer. + + The user MUST NOT set the callback on this buffer. + + When filters are being used, the filters need to be manually + triggered if the output buffer was manipulated. + + @param bufev the bufferevent from which to get the evbuffer + @return the evbuffer object for the output buffer + */ + +EVENT2_EXPORT_SYMBOL +struct evbuffer *bufferevent_get_output(struct bufferevent *bufev); + +/** + Enable a bufferevent. + + @param bufev the bufferevent to be enabled + @param event any combination of EV_READ | EV_WRITE. + @return 0 if successful, or -1 if an error occurred + @see bufferevent_disable() + */ +EVENT2_EXPORT_SYMBOL +int bufferevent_enable(struct bufferevent *bufev, short event); + +/** + Disable a bufferevent. + + @param bufev the bufferevent to be disabled + @param event any combination of EV_READ | EV_WRITE. + @return 0 if successful, or -1 if an error occurred + @see bufferevent_enable() + */ +EVENT2_EXPORT_SYMBOL +int bufferevent_disable(struct bufferevent *bufev, short event); + +/** + Return the events that are enabled on a given bufferevent. + + @param bufev the bufferevent to inspect + @return A combination of EV_READ | EV_WRITE + */ +EVENT2_EXPORT_SYMBOL +short bufferevent_get_enabled(struct bufferevent *bufev); + +/** + Set the read and write timeout for a bufferevent. + + A bufferevent's timeout will fire the first time that the indicated + amount of time has elapsed since a successful read or write operation, + during which the bufferevent was trying to read or write. + + (In other words, if reading or writing is disabled, or if the + bufferevent's read or write operation has been suspended because + there's no data to write, or not enough banwidth, or so on, the + timeout isn't active. The timeout only becomes active when we we're + willing to actually read or write.) + + Calling bufferevent_enable or setting a timeout for a bufferevent + whose timeout is already pending resets its timeout. + + If the timeout elapses, the corresponding operation (EV_READ or + EV_WRITE) becomes disabled until you re-enable it again. The + bufferevent's event callback is called with the + BEV_EVENT_TIMEOUT|BEV_EVENT_READING or + BEV_EVENT_TIMEOUT|BEV_EVENT_WRITING. + + @param bufev the bufferevent to be modified + @param timeout_read the read timeout, or NULL + @param timeout_write the write timeout, or NULL + */ +EVENT2_EXPORT_SYMBOL +int bufferevent_set_timeouts(struct bufferevent *bufev, + const struct timeval *timeout_read, const struct timeval *timeout_write); + +/** + Sets the watermarks for read and write events. + + On input, a bufferevent does not invoke the user read callback unless + there is at least low watermark data in the buffer. If the read buffer + is beyond the high watermark, the bufferevent stops reading from the network. + + On output, the user write callback is invoked whenever the buffered data + falls below the low watermark. Filters that write to this bufev will try + not to write more bytes to this buffer than the high watermark would allow, + except when flushing. + + @param bufev the bufferevent to be modified + @param events EV_READ, EV_WRITE or both + @param lowmark the lower watermark to set + @param highmark the high watermark to set +*/ + +EVENT2_EXPORT_SYMBOL +void bufferevent_setwatermark(struct bufferevent *bufev, short events, + size_t lowmark, size_t highmark); + +/** + Retrieves the watermarks for read or write events. + Returns non-zero if events contains not only EV_READ or EV_WRITE. + Returns zero if events equal EV_READ or EV_WRITE + + @param bufev the bufferevent to be examined + @param events EV_READ or EV_WRITE + @param lowmark receives the lower watermark if not NULL + @param highmark receives the high watermark if not NULL +*/ +EVENT2_EXPORT_SYMBOL +int bufferevent_getwatermark(struct bufferevent *bufev, short events, + size_t *lowmark, size_t *highmark); + +/** + Acquire the lock on a bufferevent. Has no effect if locking was not + enabled with BEV_OPT_THREADSAFE. + */ +EVENT2_EXPORT_SYMBOL +void bufferevent_lock(struct bufferevent *bufev); + +/** + Release the lock on a bufferevent. Has no effect if locking was not + enabled with BEV_OPT_THREADSAFE. + */ +EVENT2_EXPORT_SYMBOL +void bufferevent_unlock(struct bufferevent *bufev); + + +/** + * Public interface to manually increase the reference count of a bufferevent + * this is useful in situations where a user may reference the bufferevent + * somewhere eles (unknown to libevent) + * + * @param bufev the bufferevent to increase the refcount on + * + */ +EVENT2_EXPORT_SYMBOL +void bufferevent_incref(struct bufferevent *bufev); + +/** + * Public interface to manually decrement the reference count of a bufferevent + * + * Warning: make sure you know what you're doing. This is mainly used in + * conjunction with bufferevent_incref(). This will free up all data associated + * with a bufferevent if the reference count hits 0. + * + * @param bufev the bufferevent to decrement the refcount on + * + * @return 1 if the bufferevent was freed, otherwise 0 (still referenced) + */ +EVENT2_EXPORT_SYMBOL +int bufferevent_decref(struct bufferevent *bufev); + +/** + Flags that can be passed into filters to let them know how to + deal with the incoming data. +*/ +enum bufferevent_flush_mode { + /** usually set when processing data */ + BEV_NORMAL = 0, + + /** want to checkpoint all data sent. */ + BEV_FLUSH = 1, + + /** encountered EOF on read or done sending data */ + BEV_FINISHED = 2 +}; + +/** + Triggers the bufferevent to produce more data if possible. + + @param bufev the bufferevent object + @param iotype either EV_READ or EV_WRITE or both. + @param mode either BEV_NORMAL or BEV_FLUSH or BEV_FINISHED + @return -1 on failure, 0 if no data was produces, 1 if data was produced + */ +EVENT2_EXPORT_SYMBOL +int bufferevent_flush(struct bufferevent *bufev, + short iotype, + enum bufferevent_flush_mode mode); + +/** + Flags for bufferevent_trigger(_event) that modify when and how to trigger + the callback. +*/ +enum bufferevent_trigger_options { + /** trigger the callback regardless of the watermarks */ + BEV_TRIG_IGNORE_WATERMARKS = (1<<16), + + /** defer even if the callbacks are not */ + BEV_TRIG_DEFER_CALLBACKS = BEV_OPT_DEFER_CALLBACKS + + /* (Note: for internal reasons, these need to be disjoint from + * bufferevent_options, except when they mean the same thing. */ +}; + +/** + Triggers bufferevent data callbacks. + + The function will honor watermarks unless options contain + BEV_TRIG_IGNORE_WATERMARKS. If the options contain BEV_OPT_DEFER_CALLBACKS, + the callbacks are deferred. + + @param bufev the bufferevent object + @param iotype either EV_READ or EV_WRITE or both. + @param options + */ +EVENT2_EXPORT_SYMBOL +void bufferevent_trigger(struct bufferevent *bufev, short iotype, + int options); + +/** + Triggers the bufferevent event callback. + + If the options contain BEV_OPT_DEFER_CALLBACKS, the callbacks are deferred. + + @param bufev the bufferevent object + @param what the flags to pass onto the event callback + @param options + */ +EVENT2_EXPORT_SYMBOL +void bufferevent_trigger_event(struct bufferevent *bufev, short what, + int options); + +/** + @name Filtering support + + @{ +*/ +/** + Values that filters can return. + */ +enum bufferevent_filter_result { + /** everything is okay */ + BEV_OK = 0, + + /** the filter needs to read more data before output */ + BEV_NEED_MORE = 1, + + /** the filter encountered a critical error, no further data + can be processed. */ + BEV_ERROR = 2 +}; + +/** A callback function to implement a filter for a bufferevent. + + @param src An evbuffer to drain data from. + @param dst An evbuffer to add data to. + @param limit A suggested upper bound of bytes to write to dst. + The filter may ignore this value, but doing so means that + it will overflow the high-water mark associated with dst. + -1 means "no limit". + @param mode Whether we should write data as may be convenient + (BEV_NORMAL), or flush as much data as we can (BEV_FLUSH), + or flush as much as we can, possibly including an end-of-stream + marker (BEV_FINISH). + @param ctx A user-supplied pointer. + + @return BEV_OK if we wrote some data; BEV_NEED_MORE if we can't + produce any more output until we get some input; and BEV_ERROR + on an error. + */ +typedef enum bufferevent_filter_result (*bufferevent_filter_cb)( + struct evbuffer *src, struct evbuffer *dst, ev_ssize_t dst_limit, + enum bufferevent_flush_mode mode, void *ctx); + +/** + Allocate a new filtering bufferevent on top of an existing bufferevent. + + @param underlying the underlying bufferevent. + @param input_filter The filter to apply to data we read from the underlying + bufferevent + @param output_filter The filer to apply to data we write to the underlying + bufferevent + @param options A bitfield of bufferevent options. + @param free_context A function to use to free the filter context when + this bufferevent is freed. + @param ctx A context pointer to pass to the filter functions. + */ +EVENT2_EXPORT_SYMBOL +struct bufferevent * +bufferevent_filter_new(struct bufferevent *underlying, + bufferevent_filter_cb input_filter, + bufferevent_filter_cb output_filter, + int options, + void (*free_context)(void *), + void *ctx); +/**@}*/ + +/** + Allocate a pair of linked bufferevents. The bufferevents behave as would + two bufferevent_sock instances connected to opposite ends of a + socketpair(), except that no internal socketpair is allocated. + + @param base The event base to associate with the socketpair. + @param options A set of options for this bufferevent + @param pair A pointer to an array to hold the two new bufferevent objects. + @return 0 on success, -1 on failure. + */ +EVENT2_EXPORT_SYMBOL +int bufferevent_pair_new(struct event_base *base, int options, + struct bufferevent *pair[2]); + +/** + Given one bufferevent returned by bufferevent_pair_new(), returns the + other one if it still exists. Otherwise returns NULL. + */ +EVENT2_EXPORT_SYMBOL +struct bufferevent *bufferevent_pair_get_partner(struct bufferevent *bev); + +/** + Abstract type used to configure rate-limiting on a bufferevent or a group + of bufferevents. + */ +struct ev_token_bucket_cfg; + +/** + A group of bufferevents which are configured to respect the same rate + limit. +*/ +struct bufferevent_rate_limit_group; + +/** Maximum configurable rate- or burst-limit. */ +#define EV_RATE_LIMIT_MAX EV_SSIZE_MAX + +/** + Initialize and return a new object to configure the rate-limiting behavior + of bufferevents. + + @param read_rate The maximum number of bytes to read per tick on + average. + @param read_burst The maximum number of bytes to read in any single tick. + @param write_rate The maximum number of bytes to write per tick on + average. + @param write_burst The maximum number of bytes to write in any single tick. + @param tick_len The length of a single tick. Defaults to one second. + Any fractions of a millisecond are ignored. + + Note that all rate-limits hare are currently best-effort: future versions + of Libevent may implement them more tightly. + */ +EVENT2_EXPORT_SYMBOL +struct ev_token_bucket_cfg *ev_token_bucket_cfg_new( + size_t read_rate, size_t read_burst, + size_t write_rate, size_t write_burst, + const struct timeval *tick_len); + +/** Free all storage held in 'cfg'. + + Note: 'cfg' is not currently reference-counted; it is not safe to free it + until no bufferevent is using it. + */ +EVENT2_EXPORT_SYMBOL +void ev_token_bucket_cfg_free(struct ev_token_bucket_cfg *cfg); + +/** + Set the rate-limit of a the bufferevent 'bev' to the one specified in + 'cfg'. If 'cfg' is NULL, disable any per-bufferevent rate-limiting on + 'bev'. + + Note that only some bufferevent types currently respect rate-limiting. + They are: socket-based bufferevents (normal and IOCP-based), and SSL-based + bufferevents. + + Return 0 on sucess, -1 on failure. + */ +EVENT2_EXPORT_SYMBOL +int bufferevent_set_rate_limit(struct bufferevent *bev, + struct ev_token_bucket_cfg *cfg); + +/** + Create a new rate-limit group for bufferevents. A rate-limit group + constrains the maximum number of bytes sent and received, in toto, + by all of its bufferevents. + + @param base An event_base to run any necessary timeouts for the group. + Note that all bufferevents in the group do not necessarily need to share + this event_base. + @param cfg The rate-limit for this group. + + Note that all rate-limits hare are currently best-effort: future versions + of Libevent may implement them more tightly. + + Note also that only some bufferevent types currently respect rate-limiting. + They are: socket-based bufferevents (normal and IOCP-based), and SSL-based + bufferevents. + */ +EVENT2_EXPORT_SYMBOL +struct bufferevent_rate_limit_group *bufferevent_rate_limit_group_new( + struct event_base *base, + const struct ev_token_bucket_cfg *cfg); +/** + Change the rate-limiting settings for a given rate-limiting group. + + Return 0 on success, -1 on failure. +*/ +EVENT2_EXPORT_SYMBOL +int bufferevent_rate_limit_group_set_cfg( + struct bufferevent_rate_limit_group *, + const struct ev_token_bucket_cfg *); + +/** + Change the smallest quantum we're willing to allocate to any single + bufferevent in a group for reading or writing at a time. + + The rationale is that, because of TCP/IP protocol overheads and kernel + behavior, if a rate-limiting group is so tight on bandwidth that you're + only willing to send 1 byte per tick per bufferevent, you might instead + want to batch up the reads and writes so that you send N bytes per + 1/N of the bufferevents (chosen at random) each tick, so you still wind + up send 1 byte per tick per bufferevent on average, but you don't send + so many tiny packets. + + The default min-share is currently 64 bytes. + + Returns 0 on success, -1 on faulre. + */ +EVENT2_EXPORT_SYMBOL +int bufferevent_rate_limit_group_set_min_share( + struct bufferevent_rate_limit_group *, size_t); + +/** + Free a rate-limiting group. The group must have no members when + this function is called. +*/ +EVENT2_EXPORT_SYMBOL +void bufferevent_rate_limit_group_free(struct bufferevent_rate_limit_group *); + +/** + Add 'bev' to the list of bufferevents whose aggregate reading and writing + is restricted by 'g'. If 'g' is NULL, remove 'bev' from its current group. + + A bufferevent may belong to no more than one rate-limit group at a time. + If 'bev' is already a member of a group, it will be removed from its old + group before being added to 'g'. + + Return 0 on success and -1 on failure. + */ +EVENT2_EXPORT_SYMBOL +int bufferevent_add_to_rate_limit_group(struct bufferevent *bev, + struct bufferevent_rate_limit_group *g); + +/** Remove 'bev' from its current rate-limit group (if any). */ +EVENT2_EXPORT_SYMBOL +int bufferevent_remove_from_rate_limit_group(struct bufferevent *bev); + +/** + Set the size limit for single read operation. + + Set to 0 for a reasonable default. + + Return 0 on success and -1 on failure. + */ +EVENT2_EXPORT_SYMBOL +int bufferevent_set_max_single_read(struct bufferevent *bev, size_t size); + +/** + Set the size limit for single write operation. + + Set to 0 for a reasonable default. + + Return 0 on success and -1 on failure. + */ +EVENT2_EXPORT_SYMBOL +int bufferevent_set_max_single_write(struct bufferevent *bev, size_t size); + +/** Get the current size limit for single read operation. */ +EVENT2_EXPORT_SYMBOL +ev_ssize_t bufferevent_get_max_single_read(struct bufferevent *bev); + +/** Get the current size limit for single write operation. */ +EVENT2_EXPORT_SYMBOL +ev_ssize_t bufferevent_get_max_single_write(struct bufferevent *bev); + +/** + @name Rate limit inspection + + Return the current read or write bucket size for a bufferevent. + If it is not configured with a per-bufferevent ratelimit, return + EV_SSIZE_MAX. This function does not inspect the group limit, if any. + Note that it can return a negative value if the bufferevent has been + made to read or write more than its limit. + + @{ + */ +EVENT2_EXPORT_SYMBOL +ev_ssize_t bufferevent_get_read_limit(struct bufferevent *bev); +EVENT2_EXPORT_SYMBOL +ev_ssize_t bufferevent_get_write_limit(struct bufferevent *bev); +/*@}*/ + +EVENT2_EXPORT_SYMBOL +ev_ssize_t bufferevent_get_max_to_read(struct bufferevent *bev); +EVENT2_EXPORT_SYMBOL +ev_ssize_t bufferevent_get_max_to_write(struct bufferevent *bev); + +EVENT2_EXPORT_SYMBOL +const struct ev_token_bucket_cfg *bufferevent_get_token_bucket_cfg(const struct bufferevent * bev); + +/** + @name Group Rate limit inspection + + Return the read or write bucket size for a bufferevent rate limit + group. Note that it can return a negative value if bufferevents in + the group have been made to read or write more than their limits. + + @{ + */ +EVENT2_EXPORT_SYMBOL +ev_ssize_t bufferevent_rate_limit_group_get_read_limit( + struct bufferevent_rate_limit_group *); +EVENT2_EXPORT_SYMBOL +ev_ssize_t bufferevent_rate_limit_group_get_write_limit( + struct bufferevent_rate_limit_group *); +/*@}*/ + +/** + @name Rate limit manipulation + + Subtract a number of bytes from a bufferevent's read or write bucket. + The decrement value can be negative, if you want to manually refill + the bucket. If the change puts the bucket above or below zero, the + bufferevent will resume or suspend reading writing as appropriate. + These functions make no change in the buckets for the bufferevent's + group, if any. + + Returns 0 on success, -1 on internal error. + + @{ + */ +EVENT2_EXPORT_SYMBOL +int bufferevent_decrement_read_limit(struct bufferevent *bev, ev_ssize_t decr); +EVENT2_EXPORT_SYMBOL +int bufferevent_decrement_write_limit(struct bufferevent *bev, ev_ssize_t decr); +/*@}*/ + +/** + @name Group rate limit manipulation + + Subtract a number of bytes from a bufferevent rate-limiting group's + read or write bucket. The decrement value can be negative, if you + want to manually refill the bucket. If the change puts the bucket + above or below zero, the bufferevents in the group will resume or + suspend reading writing as appropriate. + + Returns 0 on success, -1 on internal error. + + @{ + */ +EVENT2_EXPORT_SYMBOL +int bufferevent_rate_limit_group_decrement_read( + struct bufferevent_rate_limit_group *, ev_ssize_t); +EVENT2_EXPORT_SYMBOL +int bufferevent_rate_limit_group_decrement_write( + struct bufferevent_rate_limit_group *, ev_ssize_t); +/*@}*/ + + +/** + * Inspect the total bytes read/written on a group. + * + * Set the variable pointed to by total_read_out to the total number of bytes + * ever read on grp, and the variable pointed to by total_written_out to the + * total number of bytes ever written on grp. */ +EVENT2_EXPORT_SYMBOL +void bufferevent_rate_limit_group_get_totals( + struct bufferevent_rate_limit_group *grp, + ev_uint64_t *total_read_out, ev_uint64_t *total_written_out); + +/** + * Reset the total bytes read/written on a group. + * + * Reset the number of bytes read or written on grp as given by + * bufferevent_rate_limit_group_reset_totals(). */ +EVENT2_EXPORT_SYMBOL +void +bufferevent_rate_limit_group_reset_totals( + struct bufferevent_rate_limit_group *grp); + +#ifdef __cplusplus +} +#endif + +#endif /* EVENT2_BUFFEREVENT_H_INCLUDED_ */ diff --git a/include/event2/bufferevent_compat.h b/include/event2/bufferevent_compat.h new file mode 100644 index 000000000000..65482042f9d1 --- /dev/null +++ b/include/event2/bufferevent_compat.h @@ -0,0 +1,100 @@ +/* + * Copyright (c) 2007-2012 Niels Provos, Nick Mathewson + * Copyright (c) 2000-2007 Niels Provos <provos@citi.umich.edu> + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#ifndef EVENT2_BUFFEREVENT_COMPAT_H_INCLUDED_ +#define EVENT2_BUFFEREVENT_COMPAT_H_INCLUDED_ + +#define evbuffercb bufferevent_data_cb +#define everrorcb bufferevent_event_cb + +/** + Create a new bufferevent for an fd. + + This function is deprecated. Use bufferevent_socket_new and + bufferevent_set_callbacks instead. + + Libevent provides an abstraction on top of the regular event callbacks. + This abstraction is called a buffered event. A buffered event provides + input and output buffers that get filled and drained automatically. The + user of a buffered event no longer deals directly with the I/O, but + instead is reading from input and writing to output buffers. + + Once initialized, the bufferevent structure can be used repeatedly with + bufferevent_enable() and bufferevent_disable(). + + When read enabled the bufferevent will try to read from the file descriptor + and call the read callback. The write callback is executed whenever the + output buffer is drained below the write low watermark, which is 0 by + default. + + If multiple bases are in use, bufferevent_base_set() must be called before + enabling the bufferevent for the first time. + + @deprecated This function is deprecated because it uses the current + event base, and as such can be error prone for multithreaded programs. + Use bufferevent_socket_new() instead. + + @param fd the file descriptor from which data is read and written to. + This file descriptor is not allowed to be a pipe(2). + @param readcb callback to invoke when there is data to be read, or NULL if + no callback is desired + @param writecb callback to invoke when the file descriptor is ready for + writing, or NULL if no callback is desired + @param errorcb callback to invoke when there is an error on the file + descriptor + @param cbarg an argument that will be supplied to each of the callbacks + (readcb, writecb, and errorcb) + @return a pointer to a newly allocated bufferevent struct, or NULL if an + error occurred + @see bufferevent_base_set(), bufferevent_free() + */ +struct bufferevent *bufferevent_new(evutil_socket_t fd, + evbuffercb readcb, evbuffercb writecb, everrorcb errorcb, void *cbarg); + + +/** + Set the read and write timeout for a buffered event. + + @param bufev the bufferevent to be modified + @param timeout_read the read timeout + @param timeout_write the write timeout + */ +void bufferevent_settimeout(struct bufferevent *bufev, + int timeout_read, int timeout_write); + +#define EVBUFFER_READ BEV_EVENT_READING +#define EVBUFFER_WRITE BEV_EVENT_WRITING +#define EVBUFFER_EOF BEV_EVENT_EOF +#define EVBUFFER_ERROR BEV_EVENT_ERROR +#define EVBUFFER_TIMEOUT BEV_EVENT_TIMEOUT + +/** macro for getting access to the input buffer of a bufferevent */ +#define EVBUFFER_INPUT(x) bufferevent_get_input(x) +/** macro for getting access to the output buffer of a bufferevent */ +#define EVBUFFER_OUTPUT(x) bufferevent_get_output(x) + +#endif diff --git a/include/event2/bufferevent_ssl.h b/include/event2/bufferevent_ssl.h new file mode 100644 index 000000000000..bf39b844a965 --- /dev/null +++ b/include/event2/bufferevent_ssl.h @@ -0,0 +1,134 @@ +/* + * Copyright (c) 2009-2012 Niels Provos and Nick Mathewson + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#ifndef EVENT2_BUFFEREVENT_SSL_H_INCLUDED_ +#define EVENT2_BUFFEREVENT_SSL_H_INCLUDED_ + +/** @file event2/bufferevent_ssl.h + + OpenSSL support for bufferevents. + */ +#include <event2/visibility.h> +#include <event2/event-config.h> +#include <event2/bufferevent.h> +#include <event2/util.h> + +#ifdef __cplusplus +extern "C" { +#endif + +/* This is what openssl's SSL objects are underneath. */ +struct ssl_st; + +/** + The state of an SSL object to be used when creating a new + SSL bufferevent. + */ +enum bufferevent_ssl_state { + BUFFEREVENT_SSL_OPEN = 0, + BUFFEREVENT_SSL_CONNECTING = 1, + BUFFEREVENT_SSL_ACCEPTING = 2 +}; + +#if defined(EVENT__HAVE_OPENSSL) || defined(EVENT_IN_DOXYGEN_) +/** + Create a new SSL bufferevent to send its data over another bufferevent. + + @param base An event_base to use to detect reading and writing. It + must also be the base for the underlying bufferevent. + @param underlying A socket to use for this SSL + @param ssl A SSL* object from openssl. + @param state The current state of the SSL connection + @param options One or more bufferevent_options + @return A new bufferevent on success, or NULL on failure +*/ +EVENT2_EXPORT_SYMBOL +struct bufferevent * +bufferevent_openssl_filter_new(struct event_base *base, + struct bufferevent *underlying, + struct ssl_st *ssl, + enum bufferevent_ssl_state state, + int options); + +/** + Create a new SSL bufferevent to send its data over an SSL * on a socket. + + @param base An event_base to use to detect reading and writing + @param fd A socket to use for this SSL + @param ssl A SSL* object from openssl. + @param state The current state of the SSL connection + @param options One or more bufferevent_options + @return A new bufferevent on success, or NULL on failure. +*/ +EVENT2_EXPORT_SYMBOL +struct bufferevent * +bufferevent_openssl_socket_new(struct event_base *base, + evutil_socket_t fd, + struct ssl_st *ssl, + enum bufferevent_ssl_state state, + int options); + +/** Control how to report dirty SSL shutdowns. + + If the peer (or the network, or an attacker) closes the TCP + connection before closing the SSL channel, and the protocol is SSL >= v3, + this is a "dirty" shutdown. If allow_dirty_shutdown is 0 (default), + this is reported as BEV_EVENT_ERROR. + + If instead allow_dirty_shutdown=1, a dirty shutdown is reported as + BEV_EVENT_EOF. + + (Note that if the protocol is < SSLv3, you will always receive + BEV_EVENT_EOF, since SSL 2 and earlier cannot distinguish a secure + connection close from a dirty one. This is one reason (among many) + not to use SSL 2.) +*/ + +EVENT2_EXPORT_SYMBOL +int bufferevent_openssl_get_allow_dirty_shutdown(struct bufferevent *bev); +EVENT2_EXPORT_SYMBOL +void bufferevent_openssl_set_allow_dirty_shutdown(struct bufferevent *bev, + int allow_dirty_shutdown); + +/** Return the underlying openssl SSL * object for an SSL bufferevent. */ +EVENT2_EXPORT_SYMBOL +struct ssl_st * +bufferevent_openssl_get_ssl(struct bufferevent *bufev); + +/** Tells a bufferevent to begin SSL renegotiation. */ +EVENT2_EXPORT_SYMBOL +int bufferevent_ssl_renegotiate(struct bufferevent *bev); + +/** Return the most recent OpenSSL error reported on an SSL bufferevent. */ +EVENT2_EXPORT_SYMBOL +unsigned long bufferevent_get_openssl_error(struct bufferevent *bev); + +#endif + +#ifdef __cplusplus +} +#endif + +#endif /* EVENT2_BUFFEREVENT_SSL_H_INCLUDED_ */ diff --git a/include/event2/bufferevent_struct.h b/include/event2/bufferevent_struct.h new file mode 100644 index 000000000000..e84c082c30cc --- /dev/null +++ b/include/event2/bufferevent_struct.h @@ -0,0 +1,116 @@ +/* + * Copyright (c) 2000-2007 Niels Provos <provos@citi.umich.edu> + * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#ifndef EVENT2_BUFFEREVENT_STRUCT_H_INCLUDED_ +#define EVENT2_BUFFEREVENT_STRUCT_H_INCLUDED_ + +/** @file event2/bufferevent_struct.h + + Data structures for bufferevents. Using these structures may hurt forward + compatibility with later versions of Libevent: be careful! + + @deprecated Use of bufferevent_struct.h is completely deprecated; these + structures are only exposed for backward compatibility with programs + written before Libevent 2.0 that used them. + */ + +#ifdef __cplusplus +extern "C" { +#endif + +#include <event2/event-config.h> +#ifdef EVENT__HAVE_SYS_TYPES_H +#include <sys/types.h> +#endif +#ifdef EVENT__HAVE_SYS_TIME_H +#include <sys/time.h> +#endif + +/* For int types. */ +#include <event2/util.h> +/* For struct event */ +#include <event2/event_struct.h> + +struct event_watermark { + size_t low; + size_t high; +}; + +/** + Shared implementation of a bufferevent. + + This type is exposed only because it was exposed in previous versions, + and some people's code may rely on manipulating it. Otherwise, you + should really not rely on the layout, size, or contents of this structure: + it is fairly volatile, and WILL change in future versions of the code. +**/ +struct bufferevent { + /** Event base for which this bufferevent was created. */ + struct event_base *ev_base; + /** Pointer to a table of function pointers to set up how this + bufferevent behaves. */ + const struct bufferevent_ops *be_ops; + + /** A read event that triggers when a timeout has happened or a socket + is ready to read data. Only used by some subtypes of + bufferevent. */ + struct event ev_read; + /** A write event that triggers when a timeout has happened or a socket + is ready to write data. Only used by some subtypes of + bufferevent. */ + struct event ev_write; + + /** An input buffer. Only the bufferevent is allowed to add data to + this buffer, though the user is allowed to drain it. */ + struct evbuffer *input; + + /** An input buffer. Only the bufferevent is allowed to drain data + from this buffer, though the user is allowed to add it. */ + struct evbuffer *output; + + struct event_watermark wm_read; + struct event_watermark wm_write; + + bufferevent_data_cb readcb; + bufferevent_data_cb writecb; + /* This should be called 'eventcb', but renaming it would break + * backward compatibility */ + bufferevent_event_cb errorcb; + void *cbarg; + + struct timeval timeout_read; + struct timeval timeout_write; + + /** Events that are currently enabled: currently EV_READ and EV_WRITE + are supported. */ + short enabled; +}; + +#ifdef __cplusplus +} +#endif + +#endif /* EVENT2_BUFFEREVENT_STRUCT_H_INCLUDED_ */ diff --git a/include/event2/dns.h b/include/event2/dns.h new file mode 100644 index 000000000000..17cd86a2ec2d --- /dev/null +++ b/include/event2/dns.h @@ -0,0 +1,717 @@ +/* + * Copyright (c) 2006-2007 Niels Provos <provos@citi.umich.edu> + * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +/* + * The original DNS code is due to Adam Langley with heavy + * modifications by Nick Mathewson. Adam put his DNS software in the + * public domain. You can find his original copyright below. Please, + * aware that the code as part of Libevent is governed by the 3-clause + * BSD license above. + * + * This software is Public Domain. To view a copy of the public domain dedication, + * visit http://creativecommons.org/licenses/publicdomain/ or send a letter to + * Creative Commons, 559 Nathan Abbott Way, Stanford, California 94305, USA. + * + * I ask and expect, but do not require, that all derivative works contain an + * attribution similar to: + * Parts developed by Adam Langley <agl@imperialviolet.org> + * + * You may wish to replace the word "Parts" with something else depending on + * the amount of original code. + * + * (Derivative works does not include programs which link against, run or include + * the source verbatim in their source distributions) + */ + +/** @file event2/dns.h + * + * Welcome, gentle reader + * + * Async DNS lookups are really a whole lot harder than they should be, + * mostly stemming from the fact that the libc resolver has never been + * very good at them. Before you use this library you should see if libc + * can do the job for you with the modern async call getaddrinfo_a + * (see http://www.imperialviolet.org/page25.html#e498). Otherwise, + * please continue. + * + * The library keeps track of the state of nameservers and will avoid + * them when they go down. Otherwise it will round robin between them. + * + * Quick start guide: + * #include "evdns.h" + * void callback(int result, char type, int count, int ttl, + * void *addresses, void *arg); + * evdns_resolv_conf_parse(DNS_OPTIONS_ALL, "/etc/resolv.conf"); + * evdns_resolve("www.hostname.com", 0, callback, NULL); + * + * When the lookup is complete the callback function is called. The + * first argument will be one of the DNS_ERR_* defines in evdns.h. + * Hopefully it will be DNS_ERR_NONE, in which case type will be + * DNS_IPv4_A, count will be the number of IP addresses, ttl is the time + * which the data can be cached for (in seconds), addresses will point + * to an array of uint32_t's and arg will be whatever you passed to + * evdns_resolve. + * + * Searching: + * + * In order for this library to be a good replacement for glibc's resolver it + * supports searching. This involves setting a list of default domains, in + * which names will be queried for. The number of dots in the query name + * determines the order in which this list is used. + * + * Searching appears to be a single lookup from the point of view of the API, + * although many DNS queries may be generated from a single call to + * evdns_resolve. Searching can also drastically slow down the resolution + * of names. + * + * To disable searching: + * 1. Never set it up. If you never call evdns_resolv_conf_parse or + * evdns_search_add then no searching will occur. + * + * 2. If you do call evdns_resolv_conf_parse then don't pass + * DNS_OPTION_SEARCH (or DNS_OPTIONS_ALL, which implies it). + * + * 3. When calling evdns_resolve, pass the DNS_QUERY_NO_SEARCH flag. + * + * The order of searches depends on the number of dots in the name. If the + * number is greater than the ndots setting then the names is first tried + * globally. Otherwise each search domain is appended in turn. + * + * The ndots setting can either be set from a resolv.conf, or by calling + * evdns_search_ndots_set. + * + * For example, with ndots set to 1 (the default) and a search domain list of + * ["myhome.net"]: + * Query: www + * Order: www.myhome.net, www. + * + * Query: www.abc + * Order: www.abc., www.abc.myhome.net + * + * Internals: + * + * Requests are kept in two queues. The first is the inflight queue. In + * this queue requests have an allocated transaction id and nameserver. + * They will soon be transmitted if they haven't already been. + * + * The second is the waiting queue. The size of the inflight ring is + * limited and all other requests wait in waiting queue for space. This + * bounds the number of concurrent requests so that we don't flood the + * nameserver. Several algorithms require a full walk of the inflight + * queue and so bounding its size keeps thing going nicely under huge + * (many thousands of requests) loads. + * + * If a nameserver loses too many requests it is considered down and we + * try not to use it. After a while we send a probe to that nameserver + * (a lookup for google.com) and, if it replies, we consider it working + * again. If the nameserver fails a probe we wait longer to try again + * with the next probe. + */ + +#ifndef EVENT2_DNS_H_INCLUDED_ +#define EVENT2_DNS_H_INCLUDED_ + +#include <event2/visibility.h> + +#ifdef __cplusplus +extern "C" { +#endif + +/* For integer types. */ +#include <event2/util.h> + +/** Error codes 0-5 are as described in RFC 1035. */ +#define DNS_ERR_NONE 0 +/** The name server was unable to interpret the query */ +#define DNS_ERR_FORMAT 1 +/** The name server was unable to process this query due to a problem with the + * name server */ +#define DNS_ERR_SERVERFAILED 2 +/** The domain name does not exist */ +#define DNS_ERR_NOTEXIST 3 +/** The name server does not support the requested kind of query */ +#define DNS_ERR_NOTIMPL 4 +/** The name server refuses to reform the specified operation for policy + * reasons */ +#define DNS_ERR_REFUSED 5 +/** The reply was truncated or ill-formatted */ +#define DNS_ERR_TRUNCATED 65 +/** An unknown error occurred */ +#define DNS_ERR_UNKNOWN 66 +/** Communication with the server timed out */ +#define DNS_ERR_TIMEOUT 67 +/** The request was canceled because the DNS subsystem was shut down. */ +#define DNS_ERR_SHUTDOWN 68 +/** The request was canceled via a call to evdns_cancel_request */ +#define DNS_ERR_CANCEL 69 +/** There were no answers and no error condition in the DNS packet. + * This can happen when you ask for an address that exists, but a record + * type that doesn't. */ +#define DNS_ERR_NODATA 70 + +#define DNS_IPv4_A 1 +#define DNS_PTR 2 +#define DNS_IPv6_AAAA 3 + +#define DNS_QUERY_NO_SEARCH 1 + +#define DNS_OPTION_SEARCH 1 +#define DNS_OPTION_NAMESERVERS 2 +#define DNS_OPTION_MISC 4 +#define DNS_OPTION_HOSTSFILE 8 +#define DNS_OPTIONS_ALL 15 + +/* Obsolete name for DNS_QUERY_NO_SEARCH */ +#define DNS_NO_SEARCH DNS_QUERY_NO_SEARCH + +/** + * The callback that contains the results from a lookup. + * - result is one of the DNS_ERR_* values (DNS_ERR_NONE for success) + * - type is either DNS_IPv4_A or DNS_PTR or DNS_IPv6_AAAA + * - count contains the number of addresses of form type + * - ttl is the number of seconds the resolution may be cached for. + * - addresses needs to be cast according to type. It will be an array of + * 4-byte sequences for ipv4, or an array of 16-byte sequences for ipv6, + * or a nul-terminated string for PTR. + */ +typedef void (*evdns_callback_type) (int result, char type, int count, int ttl, void *addresses, void *arg); + +struct evdns_base; +struct event_base; + +/** Flag for evdns_base_new: process resolv.conf. */ +#define EVDNS_BASE_INITIALIZE_NAMESERVERS 1 +/** Flag for evdns_base_new: Do not prevent the libevent event loop from + * exiting when we have no active dns requests. */ +#define EVDNS_BASE_DISABLE_WHEN_INACTIVE 0x8000 + +/** + Initialize the asynchronous DNS library. + + This function initializes support for non-blocking name resolution by + calling evdns_resolv_conf_parse() on UNIX and + evdns_config_windows_nameservers() on Windows. + + @param event_base the event base to associate the dns client with + @param flags any of EVDNS_BASE_INITIALIZE_NAMESERVERS| + EVDNS_BASE_DISABLE_WHEN_INACTIVE + @return evdns_base object if successful, or NULL if an error occurred. + @see evdns_base_free() + */ +EVENT2_EXPORT_SYMBOL +struct evdns_base * evdns_base_new(struct event_base *event_base, int initialize_nameservers); + + +/** + Shut down the asynchronous DNS resolver and terminate all active requests. + + If the 'fail_requests' option is enabled, all active requests will return + an empty result with the error flag set to DNS_ERR_SHUTDOWN. Otherwise, + the requests will be silently discarded. + + @param evdns_base the evdns base to free + @param fail_requests if zero, active requests will be aborted; if non-zero, + active requests will return DNS_ERR_SHUTDOWN. + @see evdns_base_new() + */ +EVENT2_EXPORT_SYMBOL +void evdns_base_free(struct evdns_base *base, int fail_requests); + +/** + Remove all hosts entries that have been loaded into the event_base via + evdns_base_load_hosts or via event_base_resolv_conf_parse. + + @param evdns_base the evdns base to remove outdated host addresses from + */ +EVENT2_EXPORT_SYMBOL +void evdns_base_clear_host_addresses(struct evdns_base *base); + +/** + Convert a DNS error code to a string. + + @param err the DNS error code + @return a string containing an explanation of the error code +*/ +EVENT2_EXPORT_SYMBOL +const char *evdns_err_to_string(int err); + + +/** + Add a nameserver. + + The address should be an IPv4 address in network byte order. + The type of address is chosen so that it matches in_addr.s_addr. + + @param base the evdns_base to which to add the name server + @param address an IP address in network byte order + @return 0 if successful, or -1 if an error occurred + @see evdns_base_nameserver_ip_add() + */ +EVENT2_EXPORT_SYMBOL +int evdns_base_nameserver_add(struct evdns_base *base, + unsigned long int address); + +/** + Get the number of configured nameservers. + + This returns the number of configured nameservers (not necessarily the + number of running nameservers). This is useful for double-checking + whether our calls to the various nameserver configuration functions + have been successful. + + @param base the evdns_base to which to apply this operation + @return the number of configured nameservers + @see evdns_base_nameserver_add() + */ +EVENT2_EXPORT_SYMBOL +int evdns_base_count_nameservers(struct evdns_base *base); + +/** + Remove all configured nameservers, and suspend all pending resolves. + + Resolves will not necessarily be re-attempted until evdns_base_resume() is called. + + @param base the evdns_base to which to apply this operation + @return 0 if successful, or -1 if an error occurred + @see evdns_base_resume() + */ +EVENT2_EXPORT_SYMBOL +int evdns_base_clear_nameservers_and_suspend(struct evdns_base *base); + + +/** + Resume normal operation and continue any suspended resolve requests. + + Re-attempt resolves left in limbo after an earlier call to + evdns_base_clear_nameservers_and_suspend(). + + @param base the evdns_base to which to apply this operation + @return 0 if successful, or -1 if an error occurred + @see evdns_base_clear_nameservers_and_suspend() + */ +EVENT2_EXPORT_SYMBOL +int evdns_base_resume(struct evdns_base *base); + +/** + Add a nameserver by string address. + + This function parses a n IPv4 or IPv6 address from a string and adds it as a + nameserver. It supports the following formats: + - [IPv6Address]:port + - [IPv6Address] + - IPv6Address + - IPv4Address:port + - IPv4Address + + If no port is specified, it defaults to 53. + + @param base the evdns_base to which to apply this operation + @return 0 if successful, or -1 if an error occurred + @see evdns_base_nameserver_add() + */ +EVENT2_EXPORT_SYMBOL +int evdns_base_nameserver_ip_add(struct evdns_base *base, + const char *ip_as_string); + +/** + Add a nameserver by sockaddr. + **/ +EVENT2_EXPORT_SYMBOL +int +evdns_base_nameserver_sockaddr_add(struct evdns_base *base, + const struct sockaddr *sa, ev_socklen_t len, unsigned flags); + +struct evdns_request; + +/** + Lookup an A record for a given name. + + @param base the evdns_base to which to apply this operation + @param name a DNS hostname + @param flags either 0, or DNS_QUERY_NO_SEARCH to disable searching for this query. + @param callback a callback function to invoke when the request is completed + @param ptr an argument to pass to the callback function + @return an evdns_request object if successful, or NULL if an error occurred. + @see evdns_resolve_ipv6(), evdns_resolve_reverse(), evdns_resolve_reverse_ipv6(), evdns_cancel_request() + */ +EVENT2_EXPORT_SYMBOL +struct evdns_request *evdns_base_resolve_ipv4(struct evdns_base *base, const char *name, int flags, evdns_callback_type callback, void *ptr); + +/** + Lookup an AAAA record for a given name. + + @param base the evdns_base to which to apply this operation + @param name a DNS hostname + @param flags either 0, or DNS_QUERY_NO_SEARCH to disable searching for this query. + @param callback a callback function to invoke when the request is completed + @param ptr an argument to pass to the callback function + @return an evdns_request object if successful, or NULL if an error occurred. + @see evdns_resolve_ipv4(), evdns_resolve_reverse(), evdns_resolve_reverse_ipv6(), evdns_cancel_request() + */ +EVENT2_EXPORT_SYMBOL +struct evdns_request *evdns_base_resolve_ipv6(struct evdns_base *base, const char *name, int flags, evdns_callback_type callback, void *ptr); + +struct in_addr; +struct in6_addr; + +/** + Lookup a PTR record for a given IP address. + + @param base the evdns_base to which to apply this operation + @param in an IPv4 address + @param flags either 0, or DNS_QUERY_NO_SEARCH to disable searching for this query. + @param callback a callback function to invoke when the request is completed + @param ptr an argument to pass to the callback function + @return an evdns_request object if successful, or NULL if an error occurred. + @see evdns_resolve_reverse_ipv6(), evdns_cancel_request() + */ +EVENT2_EXPORT_SYMBOL +struct evdns_request *evdns_base_resolve_reverse(struct evdns_base *base, const struct in_addr *in, int flags, evdns_callback_type callback, void *ptr); + + +/** + Lookup a PTR record for a given IPv6 address. + + @param base the evdns_base to which to apply this operation + @param in an IPv6 address + @param flags either 0, or DNS_QUERY_NO_SEARCH to disable searching for this query. + @param callback a callback function to invoke when the request is completed + @param ptr an argument to pass to the callback function + @return an evdns_request object if successful, or NULL if an error occurred. + @see evdns_resolve_reverse_ipv6(), evdns_cancel_request() + */ +EVENT2_EXPORT_SYMBOL +struct evdns_request *evdns_base_resolve_reverse_ipv6(struct evdns_base *base, const struct in6_addr *in, int flags, evdns_callback_type callback, void *ptr); + +/** + Cancels a pending DNS resolution request. + + @param base the evdns_base that was used to make the request + @param req the evdns_request that was returned by calling a resolve function + @see evdns_base_resolve_ipv4(), evdns_base_resolve_ipv6, evdns_base_resolve_reverse +*/ +EVENT2_EXPORT_SYMBOL +void evdns_cancel_request(struct evdns_base *base, struct evdns_request *req); + +/** + Set the value of a configuration option. + + The currently available configuration options are: + + ndots, timeout, max-timeouts, max-inflight, attempts, randomize-case, + bind-to, initial-probe-timeout, getaddrinfo-allow-skew. + + In versions before Libevent 2.0.3-alpha, the option name needed to end with + a colon. + + @param base the evdns_base to which to apply this operation + @param option the name of the configuration option to be modified + @param val the value to be set + @return 0 if successful, or -1 if an error occurred + */ +EVENT2_EXPORT_SYMBOL +int evdns_base_set_option(struct evdns_base *base, const char *option, const char *val); + + +/** + Parse a resolv.conf file. + + The 'flags' parameter determines what information is parsed from the + resolv.conf file. See the man page for resolv.conf for the format of this + file. + + The following directives are not parsed from the file: sortlist, rotate, + no-check-names, inet6, debug. + + If this function encounters an error, the possible return values are: 1 = + failed to open file, 2 = failed to stat file, 3 = file too large, 4 = out of + memory, 5 = short read from file, 6 = no nameservers listed in the file + + @param base the evdns_base to which to apply this operation + @param flags any of DNS_OPTION_NAMESERVERS|DNS_OPTION_SEARCH|DNS_OPTION_MISC| + DNS_OPTION_HOSTSFILE|DNS_OPTIONS_ALL + @param filename the path to the resolv.conf file + @return 0 if successful, or various positive error codes if an error + occurred (see above) + @see resolv.conf(3), evdns_config_windows_nameservers() + */ +EVENT2_EXPORT_SYMBOL +int evdns_base_resolv_conf_parse(struct evdns_base *base, int flags, const char *const filename); + +/** + Load an /etc/hosts-style file from 'hosts_fname' into 'base'. + + If hosts_fname is NULL, add minimal entries for localhost, and nothing + else. + + Note that only evdns_getaddrinfo uses the /etc/hosts entries. + + This function does not replace previously loaded hosts entries; to do that, + call evdns_base_clear_host_addresses first. + + Return 0 on success, negative on failure. +*/ +EVENT2_EXPORT_SYMBOL +int evdns_base_load_hosts(struct evdns_base *base, const char *hosts_fname); + +/** + Obtain nameserver information using the Windows API. + + Attempt to configure a set of nameservers based on platform settings on + a win32 host. Preferentially tries to use GetNetworkParams; if that fails, + looks in the registry. + + @return 0 if successful, or -1 if an error occurred + @see evdns_resolv_conf_parse() + */ +#ifdef _WIN32 +EVENT2_EXPORT_SYMBOL +int evdns_base_config_windows_nameservers(struct evdns_base *); +#define EVDNS_BASE_CONFIG_WINDOWS_NAMESERVERS_IMPLEMENTED +#endif + + +/** + Clear the list of search domains. + */ +EVENT2_EXPORT_SYMBOL +void evdns_base_search_clear(struct evdns_base *base); + + +/** + Add a domain to the list of search domains + + @param domain the domain to be added to the search list + */ +EVENT2_EXPORT_SYMBOL +void evdns_base_search_add(struct evdns_base *base, const char *domain); + + +/** + Set the 'ndots' parameter for searches. + + Sets the number of dots which, when found in a name, causes + the first query to be without any search domain. + + @param ndots the new ndots parameter + */ +EVENT2_EXPORT_SYMBOL +void evdns_base_search_ndots_set(struct evdns_base *base, const int ndots); + +/** + A callback that is invoked when a log message is generated + + @param is_warning indicates if the log message is a 'warning' + @param msg the content of the log message + */ +typedef void (*evdns_debug_log_fn_type)(int is_warning, const char *msg); + + +/** + Set the callback function to handle DNS log messages. If this + callback is not set, evdns log messages are handled with the regular + Libevent logging system. + + @param fn the callback to be invoked when a log message is generated + */ +EVENT2_EXPORT_SYMBOL +void evdns_set_log_fn(evdns_debug_log_fn_type fn); + +/** + Set a callback that will be invoked to generate transaction IDs. By + default, we pick transaction IDs based on the current clock time, which + is bad for security. + + @param fn the new callback, or NULL to use the default. + + NOTE: This function has no effect in Libevent 2.0.4-alpha and later, + since Libevent now provides its own secure RNG. + */ +EVENT2_EXPORT_SYMBOL +void evdns_set_transaction_id_fn(ev_uint16_t (*fn)(void)); + +/** + Set a callback used to generate random bytes. By default, we use + the same function as passed to evdns_set_transaction_id_fn to generate + bytes two at a time. If a function is provided here, it's also used + to generate transaction IDs. + + NOTE: This function has no effect in Libevent 2.0.4-alpha and later, + since Libevent now provides its own secure RNG. +*/ +EVENT2_EXPORT_SYMBOL +void evdns_set_random_bytes_fn(void (*fn)(char *, size_t)); + +/* + * Functions used to implement a DNS server. + */ + +struct evdns_server_request; +struct evdns_server_question; + +/** + A callback to implement a DNS server. The callback function receives a DNS + request. It should then optionally add a number of answers to the reply + using the evdns_server_request_add_*_reply functions, before calling either + evdns_server_request_respond to send the reply back, or + evdns_server_request_drop to decline to answer the request. + + @param req A newly received request + @param user_data A pointer that was passed to + evdns_add_server_port_with_base(). + */ +typedef void (*evdns_request_callback_fn_type)(struct evdns_server_request *, void *); +#define EVDNS_ANSWER_SECTION 0 +#define EVDNS_AUTHORITY_SECTION 1 +#define EVDNS_ADDITIONAL_SECTION 2 + +#define EVDNS_TYPE_A 1 +#define EVDNS_TYPE_NS 2 +#define EVDNS_TYPE_CNAME 5 +#define EVDNS_TYPE_SOA 6 +#define EVDNS_TYPE_PTR 12 +#define EVDNS_TYPE_MX 15 +#define EVDNS_TYPE_TXT 16 +#define EVDNS_TYPE_AAAA 28 + +#define EVDNS_QTYPE_AXFR 252 +#define EVDNS_QTYPE_ALL 255 + +#define EVDNS_CLASS_INET 1 + +/* flags that can be set in answers; as part of the err parameter */ +#define EVDNS_FLAGS_AA 0x400 +#define EVDNS_FLAGS_RD 0x080 + +/** Create a new DNS server port. + + @param base The event base to handle events for the server port. + @param socket A UDP socket to accept DNS requests. + @param flags Always 0 for now. + @param callback A function to invoke whenever we get a DNS request + on the socket. + @param user_data Data to pass to the callback. + @return an evdns_server_port structure for this server port. + */ +EVENT2_EXPORT_SYMBOL +struct evdns_server_port *evdns_add_server_port_with_base(struct event_base *base, evutil_socket_t socket, int flags, evdns_request_callback_fn_type callback, void *user_data); +/** Close down a DNS server port, and free associated structures. */ +EVENT2_EXPORT_SYMBOL +void evdns_close_server_port(struct evdns_server_port *port); + +/** Sets some flags in a reply we're building. + Allows setting of the AA or RD flags + */ +EVENT2_EXPORT_SYMBOL +void evdns_server_request_set_flags(struct evdns_server_request *req, int flags); + +/* Functions to add an answer to an in-progress DNS reply. + */ +EVENT2_EXPORT_SYMBOL +int evdns_server_request_add_reply(struct evdns_server_request *req, int section, const char *name, int type, int dns_class, int ttl, int datalen, int is_name, const char *data); +EVENT2_EXPORT_SYMBOL +int evdns_server_request_add_a_reply(struct evdns_server_request *req, const char *name, int n, const void *addrs, int ttl); +EVENT2_EXPORT_SYMBOL +int evdns_server_request_add_aaaa_reply(struct evdns_server_request *req, const char *name, int n, const void *addrs, int ttl); +EVENT2_EXPORT_SYMBOL +int evdns_server_request_add_ptr_reply(struct evdns_server_request *req, struct in_addr *in, const char *inaddr_name, const char *hostname, int ttl); +EVENT2_EXPORT_SYMBOL +int evdns_server_request_add_cname_reply(struct evdns_server_request *req, const char *name, const char *cname, int ttl); + +/** + Send back a response to a DNS request, and free the request structure. +*/ +EVENT2_EXPORT_SYMBOL +int evdns_server_request_respond(struct evdns_server_request *req, int err); +/** + Free a DNS request without sending back a reply. +*/ +EVENT2_EXPORT_SYMBOL +int evdns_server_request_drop(struct evdns_server_request *req); +struct sockaddr; +/** + Get the address that made a DNS request. + */ +EVENT2_EXPORT_SYMBOL +int evdns_server_request_get_requesting_addr(struct evdns_server_request *req, struct sockaddr *sa, int addr_len); + +/** Callback for evdns_getaddrinfo. */ +typedef void (*evdns_getaddrinfo_cb)(int result, struct evutil_addrinfo *res, void *arg); + +struct evdns_base; +struct evdns_getaddrinfo_request; +/** Make a non-blocking getaddrinfo request using the dns_base in 'dns_base'. + * + * If we can answer the request immediately (with an error or not!), then we + * invoke cb immediately and return NULL. Otherwise we return + * an evdns_getaddrinfo_request and invoke cb later. + * + * When the callback is invoked, we pass as its first argument the error code + * that getaddrinfo would return (or 0 for no error). As its second argument, + * we pass the evutil_addrinfo structures we found (or NULL on error). We + * pass 'arg' as the third argument. + * + * Limitations: + * + * - The AI_V4MAPPED and AI_ALL flags are not currently implemented. + * - For ai_socktype, we only handle SOCKTYPE_STREAM, SOCKTYPE_UDP, and 0. + * - For ai_protocol, we only handle IPPROTO_TCP, IPPROTO_UDP, and 0. + */ +EVENT2_EXPORT_SYMBOL +struct evdns_getaddrinfo_request *evdns_getaddrinfo( + struct evdns_base *dns_base, + const char *nodename, const char *servname, + const struct evutil_addrinfo *hints_in, + evdns_getaddrinfo_cb cb, void *arg); + +/* Cancel an in-progress evdns_getaddrinfo. This MUST NOT be called after the + * getaddrinfo's callback has been invoked. The resolves will be canceled, + * and the callback will be invoked with the error EVUTIL_EAI_CANCEL. */ +EVENT2_EXPORT_SYMBOL +void evdns_getaddrinfo_cancel(struct evdns_getaddrinfo_request *req); + +/** + Retrieve the address of the 'idx'th configured nameserver. + + @param base The evdns_base to examine. + @param idx The index of the nameserver to get the address of. + @param sa A location to receive the server's address. + @param len The number of bytes available at sa. + + @return the number of bytes written into sa on success. On failure, returns + -1 if idx is greater than the number of configured nameservers, or a + value greater than 'len' if len was not high enough. + */ +EVENT2_EXPORT_SYMBOL +int evdns_base_get_nameserver_addr(struct evdns_base *base, int idx, + struct sockaddr *sa, ev_socklen_t len); + +#ifdef __cplusplus +} +#endif + +#endif /* !EVENT2_DNS_H_INCLUDED_ */ diff --git a/include/event2/dns_compat.h b/include/event2/dns_compat.h new file mode 100644 index 000000000000..965fd65445b4 --- /dev/null +++ b/include/event2/dns_compat.h @@ -0,0 +1,336 @@ +/* + * Copyright (c) 2006-2007 Niels Provos <provos@citi.umich.edu> + * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#ifndef EVENT2_DNS_COMPAT_H_INCLUDED_ +#define EVENT2_DNS_COMPAT_H_INCLUDED_ + +/** @file event2/dns_compat.h + + Potentially non-threadsafe versions of the functions in dns.h: provided + only for backwards compatibility. + + + */ + +#ifdef __cplusplus +extern "C" { +#endif + +#include <event2/event-config.h> +#ifdef EVENT__HAVE_SYS_TYPES_H +#include <sys/types.h> +#endif +#ifdef EVENT__HAVE_SYS_TIME_H +#include <sys/time.h> +#endif + +/* For int types. */ +#include <event2/util.h> + +/** + Initialize the asynchronous DNS library. + + This function initializes support for non-blocking name resolution by + calling evdns_resolv_conf_parse() on UNIX and + evdns_config_windows_nameservers() on Windows. + + @deprecated This function is deprecated because it always uses the current + event base, and is easily confused by multiple calls to event_init(), and + so is not safe for multithreaded use. Additionally, it allocates a global + structure that only one thread can use. The replacement is + evdns_base_new(). + + @return 0 if successful, or -1 if an error occurred + @see evdns_shutdown() + */ +int evdns_init(void); + +struct evdns_base; +/** + Return the global evdns_base created by event_init() and used by the other + deprecated functions. + + @deprecated This function is deprecated because use of the global + evdns_base is error-prone. + */ +struct evdns_base *evdns_get_global_base(void); + +/** + Shut down the asynchronous DNS resolver and terminate all active requests. + + If the 'fail_requests' option is enabled, all active requests will return + an empty result with the error flag set to DNS_ERR_SHUTDOWN. Otherwise, + the requests will be silently discarded. + + @deprecated This function is deprecated because it does not allow the + caller to specify which evdns_base it applies to. The recommended + function is evdns_base_shutdown(). + + @param fail_requests if zero, active requests will be aborted; if non-zero, + active requests will return DNS_ERR_SHUTDOWN. + @see evdns_init() + */ +void evdns_shutdown(int fail_requests); + +/** + Add a nameserver. + + The address should be an IPv4 address in network byte order. + The type of address is chosen so that it matches in_addr.s_addr. + + @deprecated This function is deprecated because it does not allow the + caller to specify which evdns_base it applies to. The recommended + function is evdns_base_nameserver_add(). + + @param address an IP address in network byte order + @return 0 if successful, or -1 if an error occurred + @see evdns_nameserver_ip_add() + */ +int evdns_nameserver_add(unsigned long int address); + +/** + Get the number of configured nameservers. + + This returns the number of configured nameservers (not necessarily the + number of running nameservers). This is useful for double-checking + whether our calls to the various nameserver configuration functions + have been successful. + + @deprecated This function is deprecated because it does not allow the + caller to specify which evdns_base it applies to. The recommended + function is evdns_base_count_nameservers(). + + @return the number of configured nameservers + @see evdns_nameserver_add() + */ +int evdns_count_nameservers(void); + +/** + Remove all configured nameservers, and suspend all pending resolves. + + Resolves will not necessarily be re-attempted until evdns_resume() is called. + + @deprecated This function is deprecated because it does not allow the + caller to specify which evdns_base it applies to. The recommended + function is evdns_base_clear_nameservers_and_suspend(). + + @return 0 if successful, or -1 if an error occurred + @see evdns_resume() + */ +int evdns_clear_nameservers_and_suspend(void); + +/** + Resume normal operation and continue any suspended resolve requests. + + Re-attempt resolves left in limbo after an earlier call to + evdns_clear_nameservers_and_suspend(). + + @deprecated This function is deprecated because it does not allow the + caller to specify which evdns_base it applies to. The recommended + function is evdns_base_resume(). + + @return 0 if successful, or -1 if an error occurred + @see evdns_clear_nameservers_and_suspend() + */ +int evdns_resume(void); + +/** + Add a nameserver. + + This wraps the evdns_nameserver_add() function by parsing a string as an IP + address and adds it as a nameserver. + + @deprecated This function is deprecated because it does not allow the + caller to specify which evdns_base it applies to. The recommended + function is evdns_base_nameserver_ip_add(). + + @return 0 if successful, or -1 if an error occurred + @see evdns_nameserver_add() + */ +int evdns_nameserver_ip_add(const char *ip_as_string); + +/** + Lookup an A record for a given name. + + @deprecated This function is deprecated because it does not allow the + caller to specify which evdns_base it applies to. The recommended + function is evdns_base_resolve_ipv4(). + + @param name a DNS hostname + @param flags either 0, or DNS_QUERY_NO_SEARCH to disable searching for this query. + @param callback a callback function to invoke when the request is completed + @param ptr an argument to pass to the callback function + @return 0 if successful, or -1 if an error occurred + @see evdns_resolve_ipv6(), evdns_resolve_reverse(), evdns_resolve_reverse_ipv6() + */ +int evdns_resolve_ipv4(const char *name, int flags, evdns_callback_type callback, void *ptr); + +/** + Lookup an AAAA record for a given name. + + @param name a DNS hostname + @param flags either 0, or DNS_QUERY_NO_SEARCH to disable searching for this query. + @param callback a callback function to invoke when the request is completed + @param ptr an argument to pass to the callback function + @return 0 if successful, or -1 if an error occurred + @see evdns_resolve_ipv4(), evdns_resolve_reverse(), evdns_resolve_reverse_ipv6() + */ +int evdns_resolve_ipv6(const char *name, int flags, evdns_callback_type callback, void *ptr); + +struct in_addr; +struct in6_addr; + +/** + Lookup a PTR record for a given IP address. + + @deprecated This function is deprecated because it does not allow the + caller to specify which evdns_base it applies to. The recommended + function is evdns_base_resolve_reverse(). + + @param in an IPv4 address + @param flags either 0, or DNS_QUERY_NO_SEARCH to disable searching for this query. + @param callback a callback function to invoke when the request is completed + @param ptr an argument to pass to the callback function + @return 0 if successful, or -1 if an error occurred + @see evdns_resolve_reverse_ipv6() + */ +int evdns_resolve_reverse(const struct in_addr *in, int flags, evdns_callback_type callback, void *ptr); + +/** + Lookup a PTR record for a given IPv6 address. + + @deprecated This function is deprecated because it does not allow the + caller to specify which evdns_base it applies to. The recommended + function is evdns_base_resolve_reverse_ipv6(). + + @param in an IPv6 address + @param flags either 0, or DNS_QUERY_NO_SEARCH to disable searching for this query. + @param callback a callback function to invoke when the request is completed + @param ptr an argument to pass to the callback function + @return 0 if successful, or -1 if an error occurred + @see evdns_resolve_reverse_ipv6() + */ +int evdns_resolve_reverse_ipv6(const struct in6_addr *in, int flags, evdns_callback_type callback, void *ptr); + +/** + Set the value of a configuration option. + + The currently available configuration options are: + + ndots, timeout, max-timeouts, max-inflight, and attempts + + @deprecated This function is deprecated because it does not allow the + caller to specify which evdns_base it applies to. The recommended + function is evdns_base_set_option(). + + @param option the name of the configuration option to be modified + @param val the value to be set + @param flags Ignored. + @return 0 if successful, or -1 if an error occurred + */ +int evdns_set_option(const char *option, const char *val, int flags); + +/** + Parse a resolv.conf file. + + The 'flags' parameter determines what information is parsed from the + resolv.conf file. See the man page for resolv.conf for the format of this + file. + + The following directives are not parsed from the file: sortlist, rotate, + no-check-names, inet6, debug. + + If this function encounters an error, the possible return values are: 1 = + failed to open file, 2 = failed to stat file, 3 = file too large, 4 = out of + memory, 5 = short read from file, 6 = no nameservers listed in the file + + @deprecated This function is deprecated because it does not allow the + caller to specify which evdns_base it applies to. The recommended + function is evdns_base_resolv_conf_parse(). + + @param flags any of DNS_OPTION_NAMESERVERS|DNS_OPTION_SEARCH|DNS_OPTION_MISC| + DNS_OPTIONS_ALL + @param filename the path to the resolv.conf file + @return 0 if successful, or various positive error codes if an error + occurred (see above) + @see resolv.conf(3), evdns_config_windows_nameservers() + */ +int evdns_resolv_conf_parse(int flags, const char *const filename); + +/** + Clear the list of search domains. + + @deprecated This function is deprecated because it does not allow the + caller to specify which evdns_base it applies to. The recommended + function is evdns_base_search_clear(). + */ +void evdns_search_clear(void); + +/** + Add a domain to the list of search domains + + @deprecated This function is deprecated because it does not allow the + caller to specify which evdns_base it applies to. The recommended + function is evdns_base_search_add(). + + @param domain the domain to be added to the search list + */ +void evdns_search_add(const char *domain); + +/** + Set the 'ndots' parameter for searches. + + Sets the number of dots which, when found in a name, causes + the first query to be without any search domain. + + @deprecated This function is deprecated because it does not allow the + caller to specify which evdns_base it applies to. The recommended + function is evdns_base_search_ndots_set(). + + @param ndots the new ndots parameter + */ +void evdns_search_ndots_set(const int ndots); + +/** + As evdns_server_new_with_base. + + @deprecated This function is deprecated because it does not allow the + caller to specify which even_base it uses. The recommended + function is evdns_add_server_port_with_base(). + +*/ +struct evdns_server_port *evdns_add_server_port(evutil_socket_t socket, int flags, evdns_request_callback_fn_type callback, void *user_data); + +#ifdef _WIN32 +int evdns_config_windows_nameservers(void); +#define EVDNS_CONFIG_WINDOWS_NAMESERVERS_IMPLEMENTED +#endif + +#ifdef __cplusplus +} +#endif + +#endif /* EVENT2_EVENT_COMPAT_H_INCLUDED_ */ diff --git a/include/event2/dns_struct.h b/include/event2/dns_struct.h new file mode 100644 index 000000000000..593a8a70b649 --- /dev/null +++ b/include/event2/dns_struct.h @@ -0,0 +1,80 @@ +/* + * Copyright (c) 2000-2007 Niels Provos <provos@citi.umich.edu> + * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#ifndef EVENT2_DNS_STRUCT_H_INCLUDED_ +#define EVENT2_DNS_STRUCT_H_INCLUDED_ + +/** @file event2/dns_struct.h + + Data structures for dns. Using these structures may hurt forward + compatibility with later versions of Libevent: be careful! + + */ + +#ifdef __cplusplus +extern "C" { +#endif + +#include <event2/event-config.h> +#ifdef EVENT__HAVE_SYS_TYPES_H +#include <sys/types.h> +#endif +#ifdef EVENT__HAVE_SYS_TIME_H +#include <sys/time.h> +#endif + +/* For int types. */ +#include <event2/util.h> + +/* + * Structures used to implement a DNS server. + */ + +struct evdns_server_request { + int flags; + int nquestions; + struct evdns_server_question **questions; +}; +struct evdns_server_question { + int type; +#ifdef __cplusplus + int dns_question_class; +#else + /* You should refer to this field as "dns_question_class". The + * name "class" works in C for backward compatibility, and will be + * removed in a future version. (1.5 or later). */ + int class; +#define dns_question_class class +#endif + char name[1]; +}; + +#ifdef __cplusplus +} +#endif + +#endif /* EVENT2_DNS_STRUCT_H_INCLUDED_ */ + diff --git a/include/event2/event.h b/include/event2/event.h new file mode 100644 index 000000000000..6e0a4f04c739 --- /dev/null +++ b/include/event2/event.h @@ -0,0 +1,1675 @@ +/* + * Copyright (c) 2000-2007 Niels Provos <provos@citi.umich.edu> + * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#ifndef EVENT2_EVENT_H_INCLUDED_ +#define EVENT2_EVENT_H_INCLUDED_ + +/** + @mainpage + + @section intro Introduction + + Libevent is an event notification library for developing scalable network + servers. The Libevent API provides a mechanism to execute a callback + function when a specific event occurs on a file descriptor or after a + timeout has been reached. Furthermore, Libevent also support callbacks due + to signals or regular timeouts. + + Libevent is meant to replace the event loop found in event driven network + servers. An application just needs to call event_base_dispatch() and then add or + remove events dynamically without having to change the event loop. + + + Currently, Libevent supports /dev/poll, kqueue(2), select(2), poll(2), + epoll(4), and evports. The internal event mechanism is completely + independent of the exposed event API, and a simple update of Libevent can + provide new functionality without having to redesign the applications. As a + result, Libevent allows for portable application development and provides + the most scalable event notification mechanism available on an operating + system. Libevent can also be used for multithreaded programs. Libevent + should compile on Linux, *BSD, Mac OS X, Solaris and, Windows. + + @section usage Standard usage + + Every program that uses Libevent must include the <event2/event.h> + header, and pass the -levent flag to the linker. (You can instead link + -levent_core if you only want the main event and buffered IO-based code, + and don't want to link any protocol code.) + + @section setup Library setup + + Before you call any other Libevent functions, you need to set up the + library. If you're going to use Libevent from multiple threads in a + multithreaded application, you need to initialize thread support -- + typically by using evthread_use_pthreads() or + evthread_use_windows_threads(). See <event2/thread.h> for more + information. + + This is also the point where you can replace Libevent's memory + management functions with event_set_mem_functions, and enable debug mode + with event_enable_debug_mode(). + + @section base Creating an event base + + Next, you need to create an event_base structure, using event_base_new() + or event_base_new_with_config(). The event_base is responsible for + keeping track of which events are "pending" (that is to say, being + watched to see if they become active) and which events are "active". + Every event is associated with a single event_base. + + @section event Event notification + + For each file descriptor that you wish to monitor, you must create an + event structure with event_new(). (You may also declare an event + structure and call event_assign() to initialize the members of the + structure.) To enable notification, you add the structure to the list + of monitored events by calling event_add(). The event structure must + remain allocated as long as it is active, so it should generally be + allocated on the heap. + + @section loop Dispatching events. + + Finally, you call event_base_dispatch() to loop and dispatch events. + You can also use event_base_loop() for more fine-grained control. + + Currently, only one thread can be dispatching a given event_base at a + time. If you want to run events in multiple threads at once, you can + either have a single event_base whose events add work to a work queue, + or you can create multiple event_base objects. + + @section bufferevent I/O Buffers + + Libevent provides a buffered I/O abstraction on top of the regular event + callbacks. This abstraction is called a bufferevent. A bufferevent + provides input and output buffers that get filled and drained + automatically. The user of a buffered event no longer deals directly + with the I/O, but instead is reading from input and writing to output + buffers. + + Once initialized via bufferevent_socket_new(), the bufferevent structure + can be used repeatedly with bufferevent_enable() and + bufferevent_disable(). Instead of reading and writing directly to a + socket, you would call bufferevent_read() and bufferevent_write(). + + When read enabled the bufferevent will try to read from the file descriptor + and call the read callback. The write callback is executed whenever the + output buffer is drained below the write low watermark, which is 0 by + default. + + See <event2/bufferevent*.h> for more information. + + @section timers Timers + + Libevent can also be used to create timers that invoke a callback after a + certain amount of time has expired. The evtimer_new() macro returns + an event struct to use as a timer. To activate the timer, call + evtimer_add(). Timers can be deactivated by calling evtimer_del(). + (These macros are thin wrappers around event_new(), event_add(), + and event_del(); you can also use those instead.) + + @section evdns Asynchronous DNS resolution + + Libevent provides an asynchronous DNS resolver that should be used instead + of the standard DNS resolver functions. See the <event2/dns.h> + functions for more detail. + + @section evhttp Event-driven HTTP servers + + Libevent provides a very simple event-driven HTTP server that can be + embedded in your program and used to service HTTP requests. + + To use this capability, you need to include the <event2/http.h> header in your + program. See that header for more information. + + @section evrpc A framework for RPC servers and clients + + Libevent provides a framework for creating RPC servers and clients. It + takes care of marshaling and unmarshaling all data structures. + + @section api API Reference + + To browse the complete documentation of the libevent API, click on any of + the following links. + + event2/event.h + The primary libevent header + + event2/thread.h + Functions for use by multithreaded programs + + event2/buffer.h and event2/bufferevent.h + Buffer management for network reading and writing + + event2/util.h + Utility functions for portable nonblocking network code + + event2/dns.h + Asynchronous DNS resolution + + event2/http.h + An embedded libevent-based HTTP server + + event2/rpc.h + A framework for creating RPC servers and clients + + */ + +/** @file event2/event.h + + Core functions for waiting for and receiving events, and using event bases. +*/ + +#include <event2/visibility.h> + +#ifdef __cplusplus +extern "C" { +#endif + +#include <event2/event-config.h> +#ifdef EVENT__HAVE_SYS_TYPES_H +#include <sys/types.h> +#endif +#ifdef EVENT__HAVE_SYS_TIME_H +#include <sys/time.h> +#endif + +#include <stdio.h> + +/* For int types. */ +#include <event2/util.h> + +/** + * Structure to hold information and state for a Libevent dispatch loop. + * + * The event_base lies at the center of Libevent; every application will + * have one. It keeps track of all pending and active events, and + * notifies your application of the active ones. + * + * This is an opaque structure; you can allocate one using + * event_base_new() or event_base_new_with_config(). + * + * @see event_base_new(), event_base_free(), event_base_loop(), + * event_base_new_with_config() + */ +struct event_base +#ifdef EVENT_IN_DOXYGEN_ +{/*Empty body so that doxygen will generate documentation here.*/} +#endif +; + +/** + * @struct event + * + * Structure to represent a single event. + * + * An event can have some underlying condition it represents: a socket + * becoming readable or writeable (or both), or a signal becoming raised. + * (An event that represents no underlying condition is still useful: you + * can use one to implement a timer, or to communicate between threads.) + * + * Generally, you can create events with event_new(), then make them + * pending with event_add(). As your event_base runs, it will run the + * callbacks of an events whose conditions are triggered. When you + * longer want the event, free it with event_free(). + * + * In more depth: + * + * An event may be "pending" (one whose condition we are watching), + * "active" (one whose condition has triggered and whose callback is about + * to run), neither, or both. Events come into existence via + * event_assign() or event_new(), and are then neither active nor pending. + * + * To make an event pending, pass it to event_add(). When doing so, you + * can also set a timeout for the event. + * + * Events become active during an event_base_loop() call when either their + * condition has triggered, or when their timeout has elapsed. You can + * also activate an event manually using event_active(). The even_base + * loop will run the callbacks of active events; after it has done so, it + * marks them as no longer active. + * + * You can make an event non-pending by passing it to event_del(). This + * also makes the event non-active. + * + * Events can be "persistent" or "non-persistent". A non-persistent event + * becomes non-pending as soon as it is triggered: thus, it only runs at + * most once per call to event_add(). A persistent event remains pending + * even when it becomes active: you'll need to event_del() it manually in + * order to make it non-pending. When a persistent event with a timeout + * becomes active, its timeout is reset: this means you can use persistent + * events to implement periodic timeouts. + * + * This should be treated as an opaque structure; you should never read or + * write any of its fields directly. For backward compatibility with old + * code, it is defined in the event2/event_struct.h header; including this + * header may make your code incompatible with other versions of Libevent. + * + * @see event_new(), event_free(), event_assign(), event_get_assignment(), + * event_add(), event_del(), event_active(), event_pending(), + * event_get_fd(), event_get_base(), event_get_events(), + * event_get_callback(), event_get_callback_arg(), + * event_priority_set() + */ +struct event +#ifdef EVENT_IN_DOXYGEN_ +{/*Empty body so that doxygen will generate documentation here.*/} +#endif +; + +/** + * Configuration for an event_base. + * + * There are many options that can be used to alter the behavior and + * implementation of an event_base. To avoid having to pass them all in a + * complex many-argument constructor, we provide an abstract data type + * wrhere you set up configation information before passing it to + * event_base_new_with_config(). + * + * @see event_config_new(), event_config_free(), event_base_new_with_config(), + * event_config_avoid_method(), event_config_require_features(), + * event_config_set_flag(), event_config_set_num_cpus_hint() + */ +struct event_config +#ifdef EVENT_IN_DOXYGEN_ +{/*Empty body so that doxygen will generate documentation here.*/} +#endif +; + +/** + * Enable some relatively expensive debugging checks in Libevent that + * would normally be turned off. Generally, these checks cause code that + * would otherwise crash mysteriously to fail earlier with an assertion + * failure. Note that this method MUST be called before any events or + * event_bases have been created. + * + * Debug mode can currently catch the following errors: + * An event is re-assigned while it is added + * Any function is called on a non-assigned event + * + * Note that debugging mode uses memory to track every event that has been + * initialized (via event_assign, event_set, or event_new) but not yet + * released (via event_free or event_debug_unassign). If you want to use + * debug mode, and you find yourself running out of memory, you will need + * to use event_debug_unassign to explicitly stop tracking events that + * are no longer considered set-up. + * + * @see event_debug_unassign() + */ +EVENT2_EXPORT_SYMBOL +void event_enable_debug_mode(void); + +/** + * When debugging mode is enabled, informs Libevent that an event should no + * longer be considered as assigned. When debugging mode is not enabled, does + * nothing. + * + * This function must only be called on a non-added event. + * + * @see event_enable_debug_mode() + */ +EVENT2_EXPORT_SYMBOL +void event_debug_unassign(struct event *); + +/** + * Create and return a new event_base to use with the rest of Libevent. + * + * @return a new event_base on success, or NULL on failure. + * + * @see event_base_free(), event_base_new_with_config() + */ +EVENT2_EXPORT_SYMBOL +struct event_base *event_base_new(void); + +/** + Reinitialize the event base after a fork + + Some event mechanisms do not survive across fork. The event base needs + to be reinitialized with the event_reinit() function. + + @param base the event base that needs to be re-initialized + @return 0 if successful, or -1 if some events could not be re-added. + @see event_base_new() +*/ +EVENT2_EXPORT_SYMBOL +int event_reinit(struct event_base *base); + +/** + Event dispatching loop + + This loop will run the event base until either there are no more pending or + active, or until something calls event_base_loopbreak() or + event_base_loopexit(). + + @param base the event_base structure returned by event_base_new() or + event_base_new_with_config() + @return 0 if successful, -1 if an error occurred, or 1 if we exited because + no events were pending or active. + @see event_base_loop() + */ +EVENT2_EXPORT_SYMBOL +int event_base_dispatch(struct event_base *); + +/** + Get the kernel event notification mechanism used by Libevent. + + @param eb the event_base structure returned by event_base_new() + @return a string identifying the kernel event mechanism (kqueue, epoll, etc.) + */ +EVENT2_EXPORT_SYMBOL +const char *event_base_get_method(const struct event_base *); + +/** + Gets all event notification mechanisms supported by Libevent. + + This functions returns the event mechanism in order preferred by + Libevent. Note that this list will include all backends that + Libevent has compiled-in support for, and will not necessarily check + your OS to see whether it has the required resources. + + @return an array with pointers to the names of support methods. + The end of the array is indicated by a NULL pointer. If an + error is encountered NULL is returned. +*/ +EVENT2_EXPORT_SYMBOL +const char **event_get_supported_methods(void); + +/** Query the current monotonic time from a the timer for a struct + * event_base. + */ +EVENT2_EXPORT_SYMBOL +int event_gettime_monotonic(struct event_base *base, struct timeval *tp); + +/** + @name event type flag + + Flags to pass to event_base_get_num_events() to specify the kinds of events + we want to aggregate counts for +*/ +/**@{*/ +/** count the number of active events, which have been triggered.*/ +#define EVENT_BASE_COUNT_ACTIVE 1U +/** count the number of virtual events, which is used to represent an internal + * condition, other than a pending event, that keeps the loop from exiting. */ +#define EVENT_BASE_COUNT_VIRTUAL 2U +/** count the number of events which have been added to event base, including + * internal events. */ +#define EVENT_BASE_COUNT_ADDED 4U +/**@}*/ + +/** + Gets the number of events in event_base, as specified in the flags. + + Since event base has some internal events added to make some of its + functionalities work, EVENT_BASE_COUNT_ADDED may return more than the + number of events you added using event_add(). + + If you pass EVENT_BASE_COUNT_ACTIVE and EVENT_BASE_COUNT_ADDED together, an + active event will be counted twice. However, this might not be the case in + future libevent versions. The return value is an indication of the work + load, but the user shouldn't rely on the exact value as this may change in + the future. + + @param eb the event_base structure returned by event_base_new() + @param flags a bitwise combination of the kinds of events to aggregate + counts for + @return the number of events specified in the flags +*/ +EVENT2_EXPORT_SYMBOL +int event_base_get_num_events(struct event_base *, unsigned int); + +/** + Get the maximum number of events in a given event_base as specified in the + flags. + + @param eb the event_base structure returned by event_base_new() + @param flags a bitwise combination of the kinds of events to aggregate + counts for + @param clear option used to reset the maximum count. + @return the number of events specified in the flags + */ +EVENT2_EXPORT_SYMBOL +int event_base_get_max_events(struct event_base *, unsigned int, int); + +/** + Allocates a new event configuration object. + + The event configuration object can be used to change the behavior of + an event base. + + @return an event_config object that can be used to store configuration, or + NULL if an error is encountered. + @see event_base_new_with_config(), event_config_free(), event_config +*/ +EVENT2_EXPORT_SYMBOL +struct event_config *event_config_new(void); + +/** + Deallocates all memory associated with an event configuration object + + @param cfg the event configuration object to be freed. +*/ +EVENT2_EXPORT_SYMBOL +void event_config_free(struct event_config *cfg); + +/** + Enters an event method that should be avoided into the configuration. + + This can be used to avoid event mechanisms that do not support certain + file descriptor types, or for debugging to avoid certain event + mechanisms. An application can make use of multiple event bases to + accommodate incompatible file descriptor types. + + @param cfg the event configuration object + @param method the name of the event method to avoid + @return 0 on success, -1 on failure. +*/ +EVENT2_EXPORT_SYMBOL +int event_config_avoid_method(struct event_config *cfg, const char *method); + +/** + A flag used to describe which features an event_base (must) provide. + + Because of OS limitations, not every Libevent backend supports every + possible feature. You can use this type with + event_config_require_features() to tell Libevent to only proceed if your + event_base implements a given feature, and you can receive this type from + event_base_get_features() to see which features are available. +*/ +enum event_method_feature { + /** Require an event method that allows edge-triggered events with EV_ET. */ + EV_FEATURE_ET = 0x01, + /** Require an event method where having one event triggered among + * many is [approximately] an O(1) operation. This excludes (for + * example) select and poll, which are approximately O(N) for N + * equal to the total number of possible events. */ + EV_FEATURE_O1 = 0x02, + /** Require an event method that allows file descriptors as well as + * sockets. */ + EV_FEATURE_FDS = 0x04, + /** Require an event method that allows you to use EV_CLOSED to detect + * connection close without the necessity of reading all the pending data. + * + * Methods that do support EV_CLOSED may not be able to provide support on + * all kernel versions. + **/ + EV_FEATURE_EARLY_CLOSE = 0x08 +}; + +/** + A flag passed to event_config_set_flag(). + + These flags change the behavior of an allocated event_base. + + @see event_config_set_flag(), event_base_new_with_config(), + event_method_feature + */ +enum event_base_config_flag { + /** Do not allocate a lock for the event base, even if we have + locking set up. + + Setting this option will make it unsafe and nonfunctional to call + functions on the base concurrently from multiple threads. + */ + EVENT_BASE_FLAG_NOLOCK = 0x01, + /** Do not check the EVENT_* environment variables when configuring + an event_base */ + EVENT_BASE_FLAG_IGNORE_ENV = 0x02, + /** Windows only: enable the IOCP dispatcher at startup + + If this flag is set then bufferevent_socket_new() and + evconn_listener_new() will use IOCP-backed implementations + instead of the usual select-based one on Windows. + */ + EVENT_BASE_FLAG_STARTUP_IOCP = 0x04, + /** Instead of checking the current time every time the event loop is + ready to run timeout callbacks, check after each timeout callback. + */ + EVENT_BASE_FLAG_NO_CACHE_TIME = 0x08, + + /** If we are using the epoll backend, this flag says that it is + safe to use Libevent's internal change-list code to batch up + adds and deletes in order to try to do as few syscalls as + possible. Setting this flag can make your code run faster, but + it may trigger a Linux bug: it is not safe to use this flag + if you have any fds cloned by dup() or its variants. Doing so + will produce strange and hard-to-diagnose bugs. + + This flag can also be activated by setting the + EVENT_EPOLL_USE_CHANGELIST environment variable. + + This flag has no effect if you wind up using a backend other than + epoll. + */ + EVENT_BASE_FLAG_EPOLL_USE_CHANGELIST = 0x10, + + /** Ordinarily, Libevent implements its time and timeout code using + the fastest monotonic timer that we have. If this flag is set, + however, we use less efficient more precise timer, assuming one is + present. + */ + EVENT_BASE_FLAG_PRECISE_TIMER = 0x20 +}; + +/** + Return a bitmask of the features implemented by an event base. This + will be a bitwise OR of one or more of the values of + event_method_feature + + @see event_method_feature + */ +EVENT2_EXPORT_SYMBOL +int event_base_get_features(const struct event_base *base); + +/** + Enters a required event method feature that the application demands. + + Note that not every feature or combination of features is supported + on every platform. Code that requests features should be prepared + to handle the case where event_base_new_with_config() returns NULL, as in: + <pre> + event_config_require_features(cfg, EV_FEATURE_ET); + base = event_base_new_with_config(cfg); + if (base == NULL) { + // We can't get edge-triggered behavior here. + event_config_require_features(cfg, 0); + base = event_base_new_with_config(cfg); + } + </pre> + + @param cfg the event configuration object + @param feature a bitfield of one or more event_method_feature values. + Replaces values from previous calls to this function. + @return 0 on success, -1 on failure. + @see event_method_feature, event_base_new_with_config() +*/ +EVENT2_EXPORT_SYMBOL +int event_config_require_features(struct event_config *cfg, int feature); + +/** + * Sets one or more flags to configure what parts of the eventual event_base + * will be initialized, and how they'll work. + * + * @see event_base_config_flags, event_base_new_with_config() + **/ +EVENT2_EXPORT_SYMBOL +int event_config_set_flag(struct event_config *cfg, int flag); + +/** + * Records a hint for the number of CPUs in the system. This is used for + * tuning thread pools, etc, for optimal performance. In Libevent 2.0, + * it is only on Windows, and only when IOCP is in use. + * + * @param cfg the event configuration object + * @param cpus the number of cpus + * @return 0 on success, -1 on failure. + */ +EVENT2_EXPORT_SYMBOL +int event_config_set_num_cpus_hint(struct event_config *cfg, int cpus); + +/** + * Record an interval and/or a number of callbacks after which the event base + * should check for new events. By default, the event base will run as many + * events are as activated at the higest activated priority before checking + * for new events. If you configure it by setting max_interval, it will check + * the time after each callback, and not allow more than max_interval to + * elapse before checking for new events. If you configure it by setting + * max_callbacks to a value >= 0, it will run no more than max_callbacks + * callbacks before checking for new events. + * + * This option can decrease the latency of high-priority events, and + * avoid priority inversions where multiple low-priority events keep us from + * polling for high-priority events, but at the expense of slightly decreasing + * the throughput. Use it with caution! + * + * @param cfg The event_base configuration object. + * @param max_interval An interval after which Libevent should stop running + * callbacks and check for more events, or NULL if there should be + * no such interval. + * @param max_callbacks A number of callbacks after which Libevent should + * stop running callbacks and check for more events, or -1 if there + * should be no such limit. + * @param min_priority A priority below which max_interval and max_callbacks + * should not be enforced. If this is set to 0, they are enforced + * for events of every priority; if it's set to 1, they're enforced + * for events of priority 1 and above, and so on. + * @return 0 on success, -1 on failure. + **/ +EVENT2_EXPORT_SYMBOL +int event_config_set_max_dispatch_interval(struct event_config *cfg, + const struct timeval *max_interval, int max_callbacks, + int min_priority); + +/** + Initialize the event API. + + Use event_base_new_with_config() to initialize a new event base, taking + the specified configuration under consideration. The configuration object + can currently be used to avoid certain event notification mechanisms. + + @param cfg the event configuration object + @return an initialized event_base that can be used to registering events, + or NULL if no event base can be created with the requested event_config. + @see event_base_new(), event_base_free(), event_init(), event_assign() +*/ +EVENT2_EXPORT_SYMBOL +struct event_base *event_base_new_with_config(const struct event_config *); + +/** + Deallocate all memory associated with an event_base, and free the base. + + Note that this function will not close any fds or free any memory passed + to event_new as the argument to callback. + + If there are any pending finalizer callbacks, this function will invoke + them. + + @param eb an event_base to be freed + */ +EVENT2_EXPORT_SYMBOL +void event_base_free(struct event_base *); + +/** + As event_free, but do not run finalizers. + + THIS IS AN EXPERIMENTAL API. IT MIGHT CHANGE BEFORE THE LIBEVENT 2.1 SERIES + BECOMES STABLE. + */ +EVENT2_EXPORT_SYMBOL +void event_base_free_nofinalize(struct event_base *); + +/** @name Log severities + */ +/**@{*/ +#define EVENT_LOG_DEBUG 0 +#define EVENT_LOG_MSG 1 +#define EVENT_LOG_WARN 2 +#define EVENT_LOG_ERR 3 +/**@}*/ + +/* Obsolete names: these are deprecated, but older programs might use them. + * They violate the reserved-identifier namespace. */ +#define _EVENT_LOG_DEBUG EVENT_LOG_DEBUG +#define _EVENT_LOG_MSG EVENT_LOG_MSG +#define _EVENT_LOG_WARN EVENT_LOG_WARN +#define _EVENT_LOG_ERR EVENT_LOG_ERR + +/** + A callback function used to intercept Libevent's log messages. + + @see event_set_log_callback + */ +typedef void (*event_log_cb)(int severity, const char *msg); +/** + Redirect Libevent's log messages. + + @param cb a function taking two arguments: an integer severity between + EVENT_LOG_DEBUG and EVENT_LOG_ERR, and a string. If cb is NULL, + then the default log is used. + + NOTE: The function you provide *must not* call any other libevent + functionality. Doing so can produce undefined behavior. + */ +EVENT2_EXPORT_SYMBOL +void event_set_log_callback(event_log_cb cb); + +/** + A function to be called if Libevent encounters a fatal internal error. + + @see event_set_fatal_callback + */ +typedef void (*event_fatal_cb)(int err); + +/** + Override Libevent's behavior in the event of a fatal internal error. + + By default, Libevent will call exit(1) if a programming error makes it + impossible to continue correct operation. This function allows you to supply + another callback instead. Note that if the function is ever invoked, + something is wrong with your program, or with Libevent: any subsequent calls + to Libevent may result in undefined behavior. + + Libevent will (almost) always log an EVENT_LOG_ERR message before calling + this function; look at the last log message to see why Libevent has died. + */ +EVENT2_EXPORT_SYMBOL +void event_set_fatal_callback(event_fatal_cb cb); + +#define EVENT_DBG_ALL 0xffffffffu +#define EVENT_DBG_NONE 0 + +/** + Turn on debugging logs and have them sent to the default log handler. + + This is a global setting; if you are going to call it, you must call this + before any calls that create an event-base. You must call it before any + multithreaded use of Libevent. + + Debug logs are verbose. + + @param which Controls which debug messages are turned on. This option is + unused for now; for forward compatibility, you must pass in the constant + "EVENT_DBG_ALL" to turn debugging logs on, or "EVENT_DBG_NONE" to turn + debugging logs off. + */ +EVENT2_EXPORT_SYMBOL +void event_enable_debug_logging(ev_uint32_t which); + +/** + Associate a different event base with an event. + + The event to be associated must not be currently active or pending. + + @param eb the event base + @param ev the event + @return 0 on success, -1 on failure. + */ +EVENT2_EXPORT_SYMBOL +int event_base_set(struct event_base *, struct event *); + +/** @name Loop flags + + These flags control the behavior of event_base_loop(). + */ +/**@{*/ +/** Block until we have an active event, then exit once all active events + * have had their callbacks run. */ +#define EVLOOP_ONCE 0x01 +/** Do not block: see which events are ready now, run the callbacks + * of the highest-priority ones, then exit. */ +#define EVLOOP_NONBLOCK 0x02 +/** Do not exit the loop because we have no pending events. Instead, keep + * running until event_base_loopexit() or event_base_loopbreak() makes us + * stop. + */ +#define EVLOOP_NO_EXIT_ON_EMPTY 0x04 +/**@}*/ + +/** + Wait for events to become active, and run their callbacks. + + This is a more flexible version of event_base_dispatch(). + + By default, this loop will run the event base until either there are no more + pending or active events, or until something calls event_base_loopbreak() or + event_base_loopexit(). You can override this behavior with the 'flags' + argument. + + @param eb the event_base structure returned by event_base_new() or + event_base_new_with_config() + @param flags any combination of EVLOOP_ONCE | EVLOOP_NONBLOCK + @return 0 if successful, -1 if an error occurred, or 1 if we exited because + no events were pending or active. + @see event_base_loopexit(), event_base_dispatch(), EVLOOP_ONCE, + EVLOOP_NONBLOCK + */ +EVENT2_EXPORT_SYMBOL +int event_base_loop(struct event_base *, int); + +/** + Exit the event loop after the specified time + + The next event_base_loop() iteration after the given timer expires will + complete normally (handling all queued events) then exit without + blocking for events again. + + Subsequent invocations of event_base_loop() will proceed normally. + + @param eb the event_base structure returned by event_init() + @param tv the amount of time after which the loop should terminate, + or NULL to exit after running all currently active events. + @return 0 if successful, or -1 if an error occurred + @see event_base_loopbreak() + */ +EVENT2_EXPORT_SYMBOL +int event_base_loopexit(struct event_base *, const struct timeval *); + +/** + Abort the active event_base_loop() immediately. + + event_base_loop() will abort the loop after the next event is completed; + event_base_loopbreak() is typically invoked from this event's callback. + This behavior is analogous to the "break;" statement. + + Subsequent invocations of event_base_loop() will proceed normally. + + @param eb the event_base structure returned by event_init() + @return 0 if successful, or -1 if an error occurred + @see event_base_loopexit() + */ +EVENT2_EXPORT_SYMBOL +int event_base_loopbreak(struct event_base *); + +/** + Tell the active event_base_loop() to scan for new events immediately. + + Calling this function makes the currently active event_base_loop() + start the loop over again (scanning for new events) after the current + event callback finishes. If the event loop is not running, this + function has no effect. + + event_base_loopbreak() is typically invoked from this event's callback. + This behavior is analogous to the "continue;" statement. + + Subsequent invocations of event loop will proceed normally. + + @param eb the event_base structure returned by event_init() + @return 0 if successful, or -1 if an error occurred + @see event_base_loopbreak() + */ +EVENT2_EXPORT_SYMBOL +int event_base_loopcontinue(struct event_base *); + +/** + Checks if the event loop was told to exit by event_base_loopexit(). + + This function will return true for an event_base at every point after + event_loopexit() is called, until the event loop is next entered. + + @param eb the event_base structure returned by event_init() + @return true if event_base_loopexit() was called on this event base, + or 0 otherwise + @see event_base_loopexit() + @see event_base_got_break() + */ +EVENT2_EXPORT_SYMBOL +int event_base_got_exit(struct event_base *); + +/** + Checks if the event loop was told to abort immediately by event_base_loopbreak(). + + This function will return true for an event_base at every point after + event_base_loopbreak() is called, until the event loop is next entered. + + @param eb the event_base structure returned by event_init() + @return true if event_base_loopbreak() was called on this event base, + or 0 otherwise + @see event_base_loopbreak() + @see event_base_got_exit() + */ +EVENT2_EXPORT_SYMBOL +int event_base_got_break(struct event_base *); + +/** + * @name event flags + * + * Flags to pass to event_new(), event_assign(), event_pending(), and + * anything else with an argument of the form "short events" + */ +/**@{*/ +/** Indicates that a timeout has occurred. It's not necessary to pass + * this flag to event_for new()/event_assign() to get a timeout. */ +#define EV_TIMEOUT 0x01 +/** Wait for a socket or FD to become readable */ +#define EV_READ 0x02 +/** Wait for a socket or FD to become writeable */ +#define EV_WRITE 0x04 +/** Wait for a POSIX signal to be raised*/ +#define EV_SIGNAL 0x08 +/** + * Persistent event: won't get removed automatically when activated. + * + * When a persistent event with a timeout becomes activated, its timeout + * is reset to 0. + */ +#define EV_PERSIST 0x10 +/** Select edge-triggered behavior, if supported by the backend. */ +#define EV_ET 0x20 +/** + * If this option is provided, then event_del() will not block in one thread + * while waiting for the event callback to complete in another thread. + * + * To use this option safely, you may need to use event_finalize() or + * event_free_finalize() in order to safely tear down an event in a + * multithreaded application. See those functions for more information. + * + * THIS IS AN EXPERIMENTAL API. IT MIGHT CHANGE BEFORE THE LIBEVENT 2.1 SERIES + * BECOMES STABLE. + **/ +#define EV_FINALIZE 0x40 +/** + * Detects connection close events. You can use this to detect when a + * connection has been closed, without having to read all the pending data + * from a connection. + * + * Not all backends support EV_CLOSED. To detect or require it, use the + * feature flag EV_FEATURE_EARLY_CLOSE. + **/ +#define EV_CLOSED 0x80 +/**@}*/ + +/** + @name evtimer_* macros + + Aliases for working with one-shot timer events */ +/**@{*/ +#define evtimer_assign(ev, b, cb, arg) \ + event_assign((ev), (b), -1, 0, (cb), (arg)) +#define evtimer_new(b, cb, arg) event_new((b), -1, 0, (cb), (arg)) +#define evtimer_add(ev, tv) event_add((ev), (tv)) +#define evtimer_del(ev) event_del(ev) +#define evtimer_pending(ev, tv) event_pending((ev), EV_TIMEOUT, (tv)) +#define evtimer_initialized(ev) event_initialized(ev) +/**@}*/ + +/** + @name evsignal_* macros + + Aliases for working with signal events + */ +/**@{*/ +#define evsignal_add(ev, tv) event_add((ev), (tv)) +#define evsignal_assign(ev, b, x, cb, arg) \ + event_assign((ev), (b), (x), EV_SIGNAL|EV_PERSIST, cb, (arg)) +#define evsignal_new(b, x, cb, arg) \ + event_new((b), (x), EV_SIGNAL|EV_PERSIST, (cb), (arg)) +#define evsignal_del(ev) event_del(ev) +#define evsignal_pending(ev, tv) event_pending((ev), EV_SIGNAL, (tv)) +#define evsignal_initialized(ev) event_initialized(ev) +/**@}*/ + +/** + A callback function for an event. + + It receives three arguments: + + @param fd An fd or signal + @param events One or more EV_* flags + @param arg A user-supplied argument. + + @see event_new() + */ +typedef void (*event_callback_fn)(evutil_socket_t, short, void *); + +/** + Return a value used to specify that the event itself must be used as the callback argument. + + The function event_new() takes a callback argument which is passed + to the event's callback function. To specify that the argument to be + passed to the callback function is the event that event_new() returns, + pass in the return value of event_self_cbarg() as the callback argument + for event_new(). + + For example: + <pre> + struct event *ev = event_new(base, sock, events, callback, %event_self_cbarg()); + </pre> + + For consistency with event_new(), it is possible to pass the return value + of this function as the callback argument for event_assign() – this + achieves the same result as passing the event in directly. + + @return a value to be passed as the callback argument to event_new() or + event_assign(). + @see event_new(), event_assign() + */ +EVENT2_EXPORT_SYMBOL +void *event_self_cbarg(void); + +/** + Allocate and asssign a new event structure, ready to be added. + + The function event_new() returns a new event that can be used in + future calls to event_add() and event_del(). The fd and events + arguments determine which conditions will trigger the event; the + callback and callback_arg arguments tell Libevent what to do when the + event becomes active. + + If events contains one of EV_READ, EV_WRITE, or EV_READ|EV_WRITE, then + fd is a file descriptor or socket that should get monitored for + readiness to read, readiness to write, or readiness for either operation + (respectively). If events contains EV_SIGNAL, then fd is a signal + number to wait for. If events contains none of those flags, then the + event can be triggered only by a timeout or by manual activation with + event_active(): In this case, fd must be -1. + + The EV_PERSIST flag can also be passed in the events argument: it makes + event_add() persistent until event_del() is called. + + The EV_ET flag is compatible with EV_READ and EV_WRITE, and supported + only by certain backends. It tells Libevent to use edge-triggered + events. + + The EV_TIMEOUT flag has no effect here. + + It is okay to have multiple events all listening on the same fds; but + they must either all be edge-triggered, or all not be edge triggerd. + + When the event becomes active, the event loop will run the provided + callbuck function, with three arguments. The first will be the provided + fd value. The second will be a bitfield of the events that triggered: + EV_READ, EV_WRITE, or EV_SIGNAL. Here the EV_TIMEOUT flag indicates + that a timeout occurred, and EV_ET indicates that an edge-triggered + event occurred. The third event will be the callback_arg pointer that + you provide. + + @param base the event base to which the event should be attached. + @param fd the file descriptor or signal to be monitored, or -1. + @param events desired events to monitor: bitfield of EV_READ, EV_WRITE, + EV_SIGNAL, EV_PERSIST, EV_ET. + @param callback callback function to be invoked when the event occurs + @param callback_arg an argument to be passed to the callback function + + @return a newly allocated struct event that must later be freed with + event_free(). + @see event_free(), event_add(), event_del(), event_assign() + */ +EVENT2_EXPORT_SYMBOL +struct event *event_new(struct event_base *, evutil_socket_t, short, event_callback_fn, void *); + + +/** + Prepare a new, already-allocated event structure to be added. + + The function event_assign() prepares the event structure ev to be used + in future calls to event_add() and event_del(). Unlike event_new(), it + doesn't allocate memory itself: it requires that you have already + allocated a struct event, probably on the heap. Doing this will + typically make your code depend on the size of the event structure, and + thereby create incompatibility with future versions of Libevent. + + The easiest way to avoid this problem is just to use event_new() and + event_free() instead. + + A slightly harder way to future-proof your code is to use + event_get_struct_event_size() to determine the required size of an event + at runtime. + + Note that it is NOT safe to call this function on an event that is + active or pending. Doing so WILL corrupt internal data structures in + Libevent, and lead to strange, hard-to-diagnose bugs. You _can_ use + event_assign to change an existing event, but only if it is not active + or pending! + + The arguments for this function, and the behavior of the events that it + makes, are as for event_new(). + + @param ev an event struct to be modified + @param base the event base to which ev should be attached. + @param fd the file descriptor to be monitored + @param events desired events to monitor; can be EV_READ and/or EV_WRITE + @param callback callback function to be invoked when the event occurs + @param callback_arg an argument to be passed to the callback function + + @return 0 if success, or -1 on invalid arguments. + + @see event_new(), event_add(), event_del(), event_base_once(), + event_get_struct_event_size() + */ +EVENT2_EXPORT_SYMBOL +int event_assign(struct event *, struct event_base *, evutil_socket_t, short, event_callback_fn, void *); + +/** + Deallocate a struct event * returned by event_new(). + + If the event is pending or active, first make it non-pending and + non-active. + */ +EVENT2_EXPORT_SYMBOL +void event_free(struct event *); + +/** + * Callback type for event_finalize and event_free_finalize(). + * + * THIS IS AN EXPERIMENTAL API. IT MIGHT CHANGE BEFORE THE LIBEVENT 2.1 SERIES + * BECOMES STABLE. + * + **/ +typedef void (*event_finalize_callback_fn)(struct event *, void *); +/** + @name Finalization functions + + These functions are used to safely tear down an event in a multithreaded + application. If you construct your events with EV_FINALIZE to avoid + deadlocks, you will need a way to remove an event in the certainty that + it will definitely not be running its callback when you deallocate it + and its callback argument. + + To do this, call one of event_finalize() or event_free_finalize with + 0 for its first argument, the event to tear down as its second argument, + and a callback function as its third argument. The callback will be + invoked as part of the event loop, with the event's priority. + + After you call a finalizer function, event_add() and event_active() will + no longer work on the event, and event_del() will produce a no-op. You + must not try to change the event's fields with event_assign() or + event_set() while the finalize callback is in progress. Once the + callback has been invoked, you should treat the event structure as + containing uninitialized memory. + + The event_free_finalize() function frees the event after it's finalized; + event_finalize() does not. + + A finalizer callback must not make events pending or active. It must not + add events, activate events, or attempt to "resucitate" the event being + finalized in any way. + + THIS IS AN EXPERIMENTAL API. IT MIGHT CHANGE BEFORE THE LIBEVENT 2.1 SERIES + BECOMES STABLE. + + @return 0 on succes, -1 on failure. + */ +/**@{*/ +EVENT2_EXPORT_SYMBOL +int event_finalize(unsigned, struct event *, event_finalize_callback_fn); +EVENT2_EXPORT_SYMBOL +int event_free_finalize(unsigned, struct event *, event_finalize_callback_fn); +/**@}*/ + +/** + Schedule a one-time event + + The function event_base_once() is similar to event_new(). However, it + schedules a callback to be called exactly once, and does not require the + caller to prepare an event structure. + + Note that in Libevent 2.0 and earlier, if the event is never triggered, the + internal memory used to hold it will never be freed. In Libevent 2.1, + the internal memory will get freed by event_base_free() if the event + is never triggered. The 'arg' value, however, will not get freed in either + case--you'll need to free that on your own if you want it to go away. + + @param base an event_base + @param fd a file descriptor to monitor, or -1 for no fd. + @param events event(s) to monitor; can be any of EV_READ | + EV_WRITE, or EV_TIMEOUT + @param callback callback function to be invoked when the event occurs + @param arg an argument to be passed to the callback function + @param timeout the maximum amount of time to wait for the event. NULL + makes an EV_READ/EV_WRITE event make forever; NULL makes an + EV_TIMEOUT event succees immediately. + @return 0 if successful, or -1 if an error occurred + */ +EVENT2_EXPORT_SYMBOL +int event_base_once(struct event_base *, evutil_socket_t, short, event_callback_fn, void *, const struct timeval *); + +/** + Add an event to the set of pending events. + + The function event_add() schedules the execution of the event 'ev' when the + condition specified by event_assign() or event_new() occurs, or when the time + specified in timeout has elapesed. If atimeout is NULL, no timeout + occurs and the function will only be + called if a matching event occurs. The event in the + ev argument must be already initialized by event_assign() or event_new() + and may not be used + in calls to event_assign() until it is no longer pending. + + If the event in the ev argument already has a scheduled timeout, calling + event_add() replaces the old timeout with the new one if tv is non-NULL. + + @param ev an event struct initialized via event_assign() or event_new() + @param timeout the maximum amount of time to wait for the event, or NULL + to wait forever + @return 0 if successful, or -1 if an error occurred + @see event_del(), event_assign(), event_new() + */ +EVENT2_EXPORT_SYMBOL +int event_add(struct event *ev, const struct timeval *timeout); + +/** + Remove a timer from a pending event without removing the event itself. + + If the event has a scheduled timeout, this function unschedules it but + leaves the event otherwise pending. + + @param ev an event struct initialized via event_assign() or event_new() + @return 0 on success, or -1 if an error occurrect. +*/ +EVENT2_EXPORT_SYMBOL +int event_remove_timer(struct event *ev); + +/** + Remove an event from the set of monitored events. + + The function event_del() will cancel the event in the argument ev. If the + event has already executed or has never been added the call will have no + effect. + + @param ev an event struct to be removed from the working set + @return 0 if successful, or -1 if an error occurred + @see event_add() + */ +EVENT2_EXPORT_SYMBOL +int event_del(struct event *); + +/** + As event_del(), but never blocks while the event's callback is running + in another thread, even if the event was constructed without the + EV_FINALIZE flag. + + THIS IS AN EXPERIMENTAL API. IT MIGHT CHANGE BEFORE THE LIBEVENT 2.1 SERIES + BECOMES STABLE. + */ +EVENT2_EXPORT_SYMBOL +int event_del_noblock(struct event *ev); +/** + As event_del(), but always blocks while the event's callback is running + in another thread, even if the event was constructed with the + EV_FINALIZE flag. + + THIS IS AN EXPERIMENTAL API. IT MIGHT CHANGE BEFORE THE LIBEVENT 2.1 SERIES + BECOMES STABLE. + */ +EVENT2_EXPORT_SYMBOL +int event_del_block(struct event *ev); + +/** + Make an event active. + + You can use this function on a pending or a non-pending event to make it + active, so that its callback will be run by event_base_dispatch() or + event_base_loop(). + + One common use in multithreaded programs is to wake the thread running + event_base_loop() from another thread. + + @param ev an event to make active. + @param res a set of flags to pass to the event's callback. + @param ncalls an obsolete argument: this is ignored. + **/ +EVENT2_EXPORT_SYMBOL +void event_active(struct event *ev, int res, short ncalls); + +/** + Checks if a specific event is pending or scheduled. + + @param ev an event struct previously passed to event_add() + @param events the requested event type; any of EV_TIMEOUT|EV_READ| + EV_WRITE|EV_SIGNAL + @param tv if this field is not NULL, and the event has a timeout, + this field is set to hold the time at which the timeout will + expire. + + @return true if the event is pending on any of the events in 'what', (that + is to say, it has been added), or 0 if the event is not added. + */ +EVENT2_EXPORT_SYMBOL +int event_pending(const struct event *ev, short events, struct timeval *tv); + +/** + If called from within the callback for an event, returns that event. + + The behavior of this function is not defined when called from outside the + callback function for an event. + */ +EVENT2_EXPORT_SYMBOL +struct event *event_base_get_running_event(struct event_base *base); + +/** + Test if an event structure might be initialized. + + The event_initialized() function can be used to check if an event has been + initialized. + + Warning: This function is only useful for distinguishing a a zeroed-out + piece of memory from an initialized event, it can easily be confused by + uninitialized memory. Thus, it should ONLY be used to distinguish an + initialized event from zero. + + @param ev an event structure to be tested + @return 1 if the structure might be initialized, or 0 if it has not been + initialized + */ +EVENT2_EXPORT_SYMBOL +int event_initialized(const struct event *ev); + +/** + Get the signal number assigned to a signal event +*/ +#define event_get_signal(ev) ((int)event_get_fd(ev)) + +/** + Get the socket or signal assigned to an event, or -1 if the event has + no socket. +*/ +EVENT2_EXPORT_SYMBOL +evutil_socket_t event_get_fd(const struct event *ev); + +/** + Get the event_base associated with an event. +*/ +EVENT2_EXPORT_SYMBOL +struct event_base *event_get_base(const struct event *ev); + +/** + Return the events (EV_READ, EV_WRITE, etc) assigned to an event. +*/ +EVENT2_EXPORT_SYMBOL +short event_get_events(const struct event *ev); + +/** + Return the callback assigned to an event. +*/ +EVENT2_EXPORT_SYMBOL +event_callback_fn event_get_callback(const struct event *ev); + +/** + Return the callback argument assigned to an event. +*/ +EVENT2_EXPORT_SYMBOL +void *event_get_callback_arg(const struct event *ev); + +/** + Return the priority of an event. + @see event_priority_init(), event_get_priority() +*/ +EVENT2_EXPORT_SYMBOL +int event_get_priority(const struct event *ev); + +/** + Extract _all_ of arguments given to construct a given event. The + event_base is copied into *base_out, the fd is copied into *fd_out, and so + on. + + If any of the "_out" arguments is NULL, it will be ignored. + */ +EVENT2_EXPORT_SYMBOL +void event_get_assignment(const struct event *event, + struct event_base **base_out, evutil_socket_t *fd_out, short *events_out, + event_callback_fn *callback_out, void **arg_out); + +/** + Return the size of struct event that the Libevent library was compiled + with. + + This will be NO GREATER than sizeof(struct event) if you're running with + the same version of Libevent that your application was built with, but + otherwise might not. + + Note that it might be SMALLER than sizeof(struct event) if some future + version of Libevent adds extra padding to the end of struct event. + We might do this to help ensure ABI-compatibility between different + versions of Libevent. + */ +EVENT2_EXPORT_SYMBOL +size_t event_get_struct_event_size(void); + +/** + Get the Libevent version. + + Note that this will give you the version of the library that you're + currently linked against, not the version of the headers that you've + compiled against. + + @return a string containing the version number of Libevent +*/ +EVENT2_EXPORT_SYMBOL +const char *event_get_version(void); + +/** + Return a numeric representation of Libevent's version. + + Note that this will give you the version of the library that you're + currently linked against, not the version of the headers you've used to + compile. + + The format uses one byte each for the major, minor, and patchlevel parts of + the version number. The low-order byte is unused. For example, version + 2.0.1-alpha has a numeric representation of 0x02000100 +*/ +EVENT2_EXPORT_SYMBOL +ev_uint32_t event_get_version_number(void); + +/** As event_get_version, but gives the version of Libevent's headers. */ +#define LIBEVENT_VERSION EVENT__VERSION +/** As event_get_version_number, but gives the version number of Libevent's + * headers. */ +#define LIBEVENT_VERSION_NUMBER EVENT__NUMERIC_VERSION + +/** Largest number of priorities that Libevent can support. */ +#define EVENT_MAX_PRIORITIES 256 +/** + Set the number of different event priorities + + By default Libevent schedules all active events with the same priority. + However, some time it is desirable to process some events with a higher + priority than others. For that reason, Libevent supports strict priority + queues. Active events with a lower priority are always processed before + events with a higher priority. + + The number of different priorities can be set initially with the + event_base_priority_init() function. This function should be called + before the first call to event_base_dispatch(). The + event_priority_set() function can be used to assign a priority to an + event. By default, Libevent assigns the middle priority to all events + unless their priority is explicitly set. + + Note that urgent-priority events can starve less-urgent events: after + running all urgent-priority callbacks, Libevent checks for more urgent + events again, before running less-urgent events. Less-urgent events + will not have their callbacks run until there are no events more urgent + than them that want to be active. + + @param eb the event_base structure returned by event_base_new() + @param npriorities the maximum number of priorities + @return 0 if successful, or -1 if an error occurred + @see event_priority_set() + */ +EVENT2_EXPORT_SYMBOL +int event_base_priority_init(struct event_base *, int); + +/** + Get the number of different event priorities. + + @param eb the event_base structure returned by event_base_new() + @return Number of different event priorities + @see event_base_priority_init() +*/ +EVENT2_EXPORT_SYMBOL +int event_base_get_npriorities(struct event_base *eb); + +/** + Assign a priority to an event. + + @param ev an event struct + @param priority the new priority to be assigned + @return 0 if successful, or -1 if an error occurred + @see event_priority_init(), event_get_priority() + */ +EVENT2_EXPORT_SYMBOL +int event_priority_set(struct event *, int); + +/** + Prepare an event_base to use a large number of timeouts with the same + duration. + + Libevent's default scheduling algorithm is optimized for having a large + number of timeouts with their durations more or less randomly + distributed. But if you have a large number of timeouts that all have + the same duration (for example, if you have a large number of + connections that all have a 10-second timeout), then you can improve + Libevent's performance by telling Libevent about it. + + To do this, call this function with the common duration. It will return a + pointer to a different, opaque timeout value. (Don't depend on its actual + contents!) When you use this timeout value in event_add(), Libevent will + schedule the event more efficiently. + + (This optimization probably will not be worthwhile until you have thousands + or tens of thousands of events with the same timeout.) + */ +EVENT2_EXPORT_SYMBOL +const struct timeval *event_base_init_common_timeout(struct event_base *base, + const struct timeval *duration); + +#if !defined(EVENT__DISABLE_MM_REPLACEMENT) || defined(EVENT_IN_DOXYGEN_) +/** + Override the functions that Libevent uses for memory management. + + Usually, Libevent uses the standard libc functions malloc, realloc, and + free to allocate memory. Passing replacements for those functions to + event_set_mem_functions() overrides this behavior. + + Note that all memory returned from Libevent will be allocated by the + replacement functions rather than by malloc() and realloc(). Thus, if you + have replaced those functions, it will not be appropriate to free() memory + that you get from Libevent. Instead, you must use the free_fn replacement + that you provided. + + Note also that if you are going to call this function, you should do so + before any call to any Libevent function that does allocation. + Otherwise, those funtions will allocate their memory using malloc(), but + then later free it using your provided free_fn. + + @param malloc_fn A replacement for malloc. + @param realloc_fn A replacement for realloc + @param free_fn A replacement for free. + **/ +EVENT2_EXPORT_SYMBOL +void event_set_mem_functions( + void *(*malloc_fn)(size_t sz), + void *(*realloc_fn)(void *ptr, size_t sz), + void (*free_fn)(void *ptr)); +/** This definition is present if Libevent was built with support for + event_set_mem_functions() */ +#define EVENT_SET_MEM_FUNCTIONS_IMPLEMENTED +#endif + +/** + Writes a human-readable description of all inserted and/or active + events to a provided stdio stream. + + This is intended for debugging; its format is not guaranteed to be the same + between libevent versions. + + @param base An event_base on which to scan the events. + @param output A stdio file to write on. + */ +EVENT2_EXPORT_SYMBOL +void event_base_dump_events(struct event_base *, FILE *); + + +/** + Activates all pending events for the given fd and event mask. + + This function activates pending events only. Events which have not been + added will not become active. + + @param base the event_base on which to activate the events. + @param fd An fd to active events on. + @param events One or more of EV_{READ,WRITE}. + */ +EVENT2_EXPORT_SYMBOL +void event_base_active_by_fd(struct event_base *base, evutil_socket_t fd, short events); + +/** + Activates all pending signals with a given signal number + + This function activates pending events only. Events which have not been + added will not become active. + + @param base the event_base on which to activate the events. + @param fd The signal to active events on. + */ +EVENT2_EXPORT_SYMBOL +void event_base_active_by_signal(struct event_base *base, int sig); + +/** + * Callback for iterating events in an event base via event_base_foreach_event + */ +typedef int (*event_base_foreach_event_cb)(const struct event_base *, const struct event *, void *); + +/** + Iterate over all added or active events events in an event loop, and invoke + a given callback on each one. + + The callback must not call any function that modifies the event base, that + modifies any event in the event base, or that adds or removes any event to + the event base. Doing so is unsupported and will lead to undefined + behavior -- likely, to crashes. + + event_base_foreach_event() holds a lock on the event_base() for the whole + time it's running: slow callbacks are not advisable. + + Note that Libevent adds some events of its own to make pieces of its + functionality work. You must not assume that the only events you'll + encounter will be the ones you added yourself. + + The callback function must return 0 to continue iteration, or some other + integer to stop iterating. + + @param base An event_base on which to scan the events. + @param fn A callback function to receive the events. + @param arg An argument passed to the callback function. + @return 0 if we iterated over every event, or the value returned by the + callback function if the loop exited early. +*/ +EVENT2_EXPORT_SYMBOL +int event_base_foreach_event(struct event_base *base, event_base_foreach_event_cb fn, void *arg); + + +/** Sets 'tv' to the current time (as returned by gettimeofday()), + looking at the cached value in 'base' if possible, and calling + gettimeofday() or clock_gettime() as appropriate if there is no + cached time. + + Generally, this value will only be cached while actually + processing event callbacks, and may be very inaccuate if your + callbacks take a long time to execute. + + Returns 0 on success, negative on failure. + */ +EVENT2_EXPORT_SYMBOL +int event_base_gettimeofday_cached(struct event_base *base, + struct timeval *tv); + +/** Update cached_tv in the 'base' to the current time + * + * You can use this function is useful for selectively increasing + * the accuracy of the cached time value in 'base' during callbacks + * that take a long time to execute. + * + * This function has no effect if the base is currently not in its + * event loop, or if timeval caching is disabled via + * EVENT_BASE_FLAG_NO_CACHE_TIME. + * + * @return 0 on success, -1 on failure + */ +EVENT2_EXPORT_SYMBOL +int event_base_update_cache_time(struct event_base *base); + +/** Release up all globally-allocated resources allocated by Libevent. + + This function does not free developer-controlled resources like + event_bases, events, bufferevents, listeners, and so on. It only releases + resources like global locks that there is no other way to free. + + It is not actually necessary to call this function before exit: every + resource that it frees would be released anyway on exit. It mainly exists + so that resource-leak debugging tools don't see Libevent as holding + resources at exit. + + You should only call this function when no other Libevent functions will + be invoked -- e.g., when cleanly exiting a program. + */ +EVENT2_EXPORT_SYMBOL +void libevent_global_shutdown(void); + +#ifdef __cplusplus +} +#endif + +#endif /* EVENT2_EVENT_H_INCLUDED_ */ diff --git a/include/event2/event_compat.h b/include/event2/event_compat.h new file mode 100644 index 000000000000..5110175a1b91 --- /dev/null +++ b/include/event2/event_compat.h @@ -0,0 +1,230 @@ +/* + * Copyright (c) 2000-2007 Niels Provos <provos@citi.umich.edu> + * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#ifndef EVENT2_EVENT_COMPAT_H_INCLUDED_ +#define EVENT2_EVENT_COMPAT_H_INCLUDED_ + +/** @file event2/event_compat.h + + Potentially non-threadsafe versions of the functions in event.h: provided + only for backwards compatibility. + + In the oldest versions of Libevent, event_base was not a first-class + structure. Instead, there was a single event base that every function + manipulated. Later, when separate event bases were added, the old functions + that didn't take an event_base argument needed to work by manipulating the + "current" event base. This could lead to thread-safety issues, and obscure, + hard-to-diagnose bugs. + + @deprecated All functions in this file are by definition deprecated. + */ +#include <event2/visibility.h> + +#ifdef __cplusplus +extern "C" { +#endif + +#include <event2/event-config.h> +#ifdef EVENT__HAVE_SYS_TYPES_H +#include <sys/types.h> +#endif +#ifdef EVENT__HAVE_SYS_TIME_H +#include <sys/time.h> +#endif + +/* For int types. */ +#include <event2/util.h> + +/** + Initialize the event API. + + The event API needs to be initialized with event_init() before it can be + used. Sets the global current base that gets used for events that have no + base associated with them. + + @deprecated This function is deprecated because it replaces the "current" + event_base, and is totally unsafe for multithreaded use. The replacement + is event_base_new(). + + @see event_base_set(), event_base_new() + */ +EVENT2_EXPORT_SYMBOL +struct event_base *event_init(void); + +/** + Loop to process events. + + Like event_base_dispatch(), but uses the "current" base. + + @deprecated This function is deprecated because it is easily confused by + multiple calls to event_init(), and because it is not safe for + multithreaded use. The replacement is event_base_dispatch(). + + @see event_base_dispatch(), event_init() + */ +EVENT2_EXPORT_SYMBOL +int event_dispatch(void); + +/** + Handle events. + + This function behaves like event_base_loop(), but uses the "current" base + + @deprecated This function is deprecated because it uses the event base from + the last call to event_init, and is therefore not safe for multithreaded + use. The replacement is event_base_loop(). + + @see event_base_loop(), event_init() +*/ +EVENT2_EXPORT_SYMBOL +int event_loop(int); + + +/** + Exit the event loop after the specified time. + + This function behaves like event_base_loopexit(), except that it uses the + "current" base. + + @deprecated This function is deprecated because it uses the event base from + the last call to event_init, and is therefore not safe for multithreaded + use. The replacement is event_base_loopexit(). + + @see event_init, event_base_loopexit() + */ +EVENT2_EXPORT_SYMBOL +int event_loopexit(const struct timeval *); + + +/** + Abort the active event_loop() immediately. + + This function behaves like event_base_loopbreakt(), except that it uses the + "current" base. + + @deprecated This function is deprecated because it uses the event base from + the last call to event_init, and is therefore not safe for multithreaded + use. The replacement is event_base_loopbreak(). + + @see event_base_loopbreak(), event_init() + */ +EVENT2_EXPORT_SYMBOL +int event_loopbreak(void); + +/** + Schedule a one-time event to occur. + + @deprecated This function is obsolete, and has been replaced by + event_base_once(). Its use is deprecated because it relies on the + "current" base configured by event_init(). + + @see event_base_once() + */ +EVENT2_EXPORT_SYMBOL +int event_once(evutil_socket_t , short, + void (*)(evutil_socket_t, short, void *), void *, const struct timeval *); + + +/** + Get the kernel event notification mechanism used by Libevent. + + @deprecated This function is obsolete, and has been replaced by + event_base_get_method(). Its use is deprecated because it relies on the + "current" base configured by event_init(). + + @see event_base_get_method() + */ +EVENT2_EXPORT_SYMBOL +const char *event_get_method(void); + + +/** + Set the number of different event priorities. + + @deprecated This function is deprecated because it is easily confused by + multiple calls to event_init(), and because it is not safe for + multithreaded use. The replacement is event_base_priority_init(). + + @see event_base_priority_init() + */ +EVENT2_EXPORT_SYMBOL +int event_priority_init(int); + +/** + Prepare an event structure to be added. + + @deprecated event_set() is not recommended for new code, because it requires + a subsequent call to event_base_set() to be safe under most circumstances. + Use event_assign() or event_new() instead. + */ +EVENT2_EXPORT_SYMBOL +void event_set(struct event *, evutil_socket_t, short, void (*)(evutil_socket_t, short, void *), void *); + +#define evtimer_set(ev, cb, arg) event_set((ev), -1, 0, (cb), (arg)) +#define evsignal_set(ev, x, cb, arg) \ + event_set((ev), (x), EV_SIGNAL|EV_PERSIST, (cb), (arg)) + + +/** + @name timeout_* macros + + @deprecated These macros are deprecated because their naming is inconsistent + with the rest of Libevent. Use the evtimer_* macros instead. + @{ + */ +#define timeout_add(ev, tv) event_add((ev), (tv)) +#define timeout_set(ev, cb, arg) event_set((ev), -1, 0, (cb), (arg)) +#define timeout_del(ev) event_del(ev) +#define timeout_pending(ev, tv) event_pending((ev), EV_TIMEOUT, (tv)) +#define timeout_initialized(ev) event_initialized(ev) +/**@}*/ + +/** + @name signal_* macros + + @deprecated These macros are deprecated because their naming is inconsistent + with the rest of Libevent. Use the evsignal_* macros instead. + @{ + */ +#define signal_add(ev, tv) event_add((ev), (tv)) +#define signal_set(ev, x, cb, arg) \ + event_set((ev), (x), EV_SIGNAL|EV_PERSIST, (cb), (arg)) +#define signal_del(ev) event_del(ev) +#define signal_pending(ev, tv) event_pending((ev), EV_SIGNAL, (tv)) +#define signal_initialized(ev) event_initialized(ev) +/**@}*/ + +#ifndef EVENT_FD +/* These macros are obsolete; use event_get_fd and event_get_signal instead. */ +#define EVENT_FD(ev) ((int)event_get_fd(ev)) +#define EVENT_SIGNAL(ev) event_get_signal(ev) +#endif + +#ifdef __cplusplus +} +#endif + +#endif /* EVENT2_EVENT_COMPAT_H_INCLUDED_ */ diff --git a/include/event2/event_struct.h b/include/event2/event_struct.h new file mode 100644 index 000000000000..1c8b71b6b0df --- /dev/null +++ b/include/event2/event_struct.h @@ -0,0 +1,180 @@ +/* + * Copyright (c) 2000-2007 Niels Provos <provos@citi.umich.edu> + * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#ifndef EVENT2_EVENT_STRUCT_H_INCLUDED_ +#define EVENT2_EVENT_STRUCT_H_INCLUDED_ + +/** @file event2/event_struct.h + + Structures used by event.h. Using these structures directly WILL harm + forward compatibility: be careful. + + No field declared in this file should be used directly in user code. Except + for historical reasons, these fields would not be exposed at all. + */ + +#ifdef __cplusplus +extern "C" { +#endif + +#include <event2/event-config.h> +#ifdef EVENT__HAVE_SYS_TYPES_H +#include <sys/types.h> +#endif +#ifdef EVENT__HAVE_SYS_TIME_H +#include <sys/time.h> +#endif + +/* For int types. */ +#include <event2/util.h> + +/* For evkeyvalq */ +#include <event2/keyvalq_struct.h> + +#define EVLIST_TIMEOUT 0x01 +#define EVLIST_INSERTED 0x02 +#define EVLIST_SIGNAL 0x04 +#define EVLIST_ACTIVE 0x08 +#define EVLIST_INTERNAL 0x10 +#define EVLIST_ACTIVE_LATER 0x20 +#define EVLIST_FINALIZING 0x40 +#define EVLIST_INIT 0x80 + +#define EVLIST_ALL 0xff + +/* Fix so that people don't have to run with <sys/queue.h> */ +#ifndef TAILQ_ENTRY +#define EVENT_DEFINED_TQENTRY_ +#define TAILQ_ENTRY(type) \ +struct { \ + struct type *tqe_next; /* next element */ \ + struct type **tqe_prev; /* address of previous next element */ \ +} +#endif /* !TAILQ_ENTRY */ + +#ifndef TAILQ_HEAD +#define EVENT_DEFINED_TQHEAD_ +#define TAILQ_HEAD(name, type) \ +struct name { \ + struct type *tqh_first; \ + struct type **tqh_last; \ +} +#endif + +/* Fix so that people don't have to run with <sys/queue.h> */ +#ifndef LIST_ENTRY +#define EVENT_DEFINED_LISTENTRY_ +#define LIST_ENTRY(type) \ +struct { \ + struct type *le_next; /* next element */ \ + struct type **le_prev; /* address of previous next element */ \ +} +#endif /* !LIST_ENTRY */ + +#ifndef LIST_HEAD +#define EVENT_DEFINED_LISTHEAD_ +#define LIST_HEAD(name, type) \ +struct name { \ + struct type *lh_first; /* first element */ \ + } +#endif /* !LIST_HEAD */ + +struct event; + +struct event_callback { + TAILQ_ENTRY(event_callback) evcb_active_next; + short evcb_flags; + ev_uint8_t evcb_pri; /* smaller numbers are higher priority */ + ev_uint8_t evcb_closure; + /* allows us to adopt for different types of events */ + union { + void (*evcb_callback)(evutil_socket_t, short, void *); + void (*evcb_selfcb)(struct event_callback *, void *); + void (*evcb_evfinalize)(struct event *, void *); + void (*evcb_cbfinalize)(struct event_callback *, void *); + } evcb_cb_union; + void *evcb_arg; +}; + +struct event_base; +struct event { + struct event_callback ev_evcallback; + + /* for managing timeouts */ + union { + TAILQ_ENTRY(event) ev_next_with_common_timeout; + int min_heap_idx; + } ev_timeout_pos; + evutil_socket_t ev_fd; + + struct event_base *ev_base; + + union { + /* used for io events */ + struct { + LIST_ENTRY (event) ev_io_next; + struct timeval ev_timeout; + } ev_io; + + /* used by signal events */ + struct { + LIST_ENTRY (event) ev_signal_next; + short ev_ncalls; + /* Allows deletes in callback */ + short *ev_pncalls; + } ev_signal; + } ev_; + + short ev_events; + short ev_res; /* result passed to event callback */ + struct timeval ev_timeout; +}; + +TAILQ_HEAD (event_list, event); + +#ifdef EVENT_DEFINED_TQENTRY_ +#undef TAILQ_ENTRY +#endif + +#ifdef EVENT_DEFINED_TQHEAD_ +#undef TAILQ_HEAD +#endif + +LIST_HEAD (event_dlist, event); + +#ifdef EVENT_DEFINED_LISTENTRY_ +#undef LIST_ENTRY +#endif + +#ifdef EVENT_DEFINED_LISTHEAD_ +#undef LIST_HEAD +#endif + +#ifdef __cplusplus +} +#endif + +#endif /* EVENT2_EVENT_STRUCT_H_INCLUDED_ */ diff --git a/include/event2/http.h b/include/event2/http.h new file mode 100644 index 000000000000..8fb5642f7f48 --- /dev/null +++ b/include/event2/http.h @@ -0,0 +1,1189 @@ +/* + * Copyright (c) 2000-2007 Niels Provos <provos@citi.umich.edu> + * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#ifndef EVENT2_HTTP_H_INCLUDED_ +#define EVENT2_HTTP_H_INCLUDED_ + +/* For int types. */ +#include <event2/util.h> +#include <event2/visibility.h> + +#ifdef __cplusplus +extern "C" { +#endif + +/* In case we haven't included the right headers yet. */ +struct evbuffer; +struct event_base; +struct bufferevent; +struct evhttp_connection; + +/** @file event2/http.h + * + * Basic support for HTTP serving. + * + * As Libevent is a library for dealing with event notification and most + * interesting applications are networked today, I have often found the + * need to write HTTP code. The following prototypes and definitions provide + * an application with a minimal interface for making HTTP requests and for + * creating a very simple HTTP server. + */ + +/* Response codes */ +#define HTTP_OK 200 /**< request completed ok */ +#define HTTP_NOCONTENT 204 /**< request does not have content */ +#define HTTP_MOVEPERM 301 /**< the uri moved permanently */ +#define HTTP_MOVETEMP 302 /**< the uri moved temporarily */ +#define HTTP_NOTMODIFIED 304 /**< page was not modified from last */ +#define HTTP_BADREQUEST 400 /**< invalid http request was made */ +#define HTTP_NOTFOUND 404 /**< could not find content for uri */ +#define HTTP_BADMETHOD 405 /**< method not allowed for this uri */ +#define HTTP_ENTITYTOOLARGE 413 /**< */ +#define HTTP_EXPECTATIONFAILED 417 /**< we can't handle this expectation */ +#define HTTP_INTERNAL 500 /**< internal error */ +#define HTTP_NOTIMPLEMENTED 501 /**< not implemented */ +#define HTTP_SERVUNAVAIL 503 /**< the server is not available */ + +struct evhttp; +struct evhttp_request; +struct evkeyvalq; +struct evhttp_bound_socket; +struct evconnlistener; +struct evdns_base; + +/** + * Create a new HTTP server. + * + * @param base (optional) the event base to receive the HTTP events + * @return a pointer to a newly initialized evhttp server structure + * @see evhttp_free() + */ +EVENT2_EXPORT_SYMBOL +struct evhttp *evhttp_new(struct event_base *base); + +/** + * Binds an HTTP server on the specified address and port. + * + * Can be called multiple times to bind the same http server + * to multiple different ports. + * + * @param http a pointer to an evhttp object + * @param address a string containing the IP address to listen(2) on + * @param port the port number to listen on + * @return 0 on success, -1 on failure. + * @see evhttp_accept_socket() + */ +EVENT2_EXPORT_SYMBOL +int evhttp_bind_socket(struct evhttp *http, const char *address, ev_uint16_t port); + +/** + * Like evhttp_bind_socket(), but returns a handle for referencing the socket. + * + * The returned pointer is not valid after \a http is freed. + * + * @param http a pointer to an evhttp object + * @param address a string containing the IP address to listen(2) on + * @param port the port number to listen on + * @return Handle for the socket on success, NULL on failure. + * @see evhttp_bind_socket(), evhttp_del_accept_socket() + */ +EVENT2_EXPORT_SYMBOL +struct evhttp_bound_socket *evhttp_bind_socket_with_handle(struct evhttp *http, const char *address, ev_uint16_t port); + +/** + * Makes an HTTP server accept connections on the specified socket. + * + * This may be useful to create a socket and then fork multiple instances + * of an http server, or when a socket has been communicated via file + * descriptor passing in situations where an http servers does not have + * permissions to bind to a low-numbered port. + * + * Can be called multiple times to have the http server listen to + * multiple different sockets. + * + * @param http a pointer to an evhttp object + * @param fd a socket fd that is ready for accepting connections + * @return 0 on success, -1 on failure. + * @see evhttp_bind_socket() + */ +EVENT2_EXPORT_SYMBOL +int evhttp_accept_socket(struct evhttp *http, evutil_socket_t fd); + +/** + * Like evhttp_accept_socket(), but returns a handle for referencing the socket. + * + * The returned pointer is not valid after \a http is freed. + * + * @param http a pointer to an evhttp object + * @param fd a socket fd that is ready for accepting connections + * @return Handle for the socket on success, NULL on failure. + * @see evhttp_accept_socket(), evhttp_del_accept_socket() + */ +EVENT2_EXPORT_SYMBOL +struct evhttp_bound_socket *evhttp_accept_socket_with_handle(struct evhttp *http, evutil_socket_t fd); + +/** + * The most low-level evhttp_bind/accept method: takes an evconnlistener, and + * returns an evhttp_bound_socket. The listener will be freed when the bound + * socket is freed. + */ +EVENT2_EXPORT_SYMBOL +struct evhttp_bound_socket *evhttp_bind_listener(struct evhttp *http, struct evconnlistener *listener); + +/** + * Return the listener used to implement a bound socket. + */ +EVENT2_EXPORT_SYMBOL +struct evconnlistener *evhttp_bound_socket_get_listener(struct evhttp_bound_socket *bound); + +typedef void evhttp_bound_socket_foreach_fn(struct evhttp_bound_socket *, void *); +/** + * Applies the function specified in the first argument to all + * evhttp_bound_sockets associated with "http". The user must not + * attempt to free or remove any connections, sockets or listeners + * in the callback "function". + * + * @param http pointer to an evhttp object + * @param function function to apply to every bound socket + * @param argument pointer value passed to function for every socket iterated + */ +EVENT2_EXPORT_SYMBOL +void evhttp_foreach_bound_socket(struct evhttp *http, evhttp_bound_socket_foreach_fn *function, void *argument); + +/** + * Makes an HTTP server stop accepting connections on the specified socket + * + * This may be useful when a socket has been sent via file descriptor passing + * and is no longer needed by the current process. + * + * If you created this bound socket with evhttp_bind_socket_with_handle or + * evhttp_accept_socket_with_handle, this function closes the fd you provided. + * If you created this bound socket with evhttp_bind_listener, this function + * frees the listener you provided. + * + * \a bound_socket is an invalid pointer after this call returns. + * + * @param http a pointer to an evhttp object + * @param bound_socket a handle returned by evhttp_{bind,accept}_socket_with_handle + * @see evhttp_bind_socket_with_handle(), evhttp_accept_socket_with_handle() + */ +EVENT2_EXPORT_SYMBOL +void evhttp_del_accept_socket(struct evhttp *http, struct evhttp_bound_socket *bound_socket); + +/** + * Get the raw file descriptor referenced by an evhttp_bound_socket. + * + * @param bound_socket a handle returned by evhttp_{bind,accept}_socket_with_handle + * @return the file descriptor used by the bound socket + * @see evhttp_bind_socket_with_handle(), evhttp_accept_socket_with_handle() + */ +EVENT2_EXPORT_SYMBOL +evutil_socket_t evhttp_bound_socket_get_fd(struct evhttp_bound_socket *bound_socket); + +/** + * Free the previously created HTTP server. + * + * Works only if no requests are currently being served. + * + * @param http the evhttp server object to be freed + * @see evhttp_start() + */ +EVENT2_EXPORT_SYMBOL +void evhttp_free(struct evhttp* http); + +/** XXX Document. */ +EVENT2_EXPORT_SYMBOL +void evhttp_set_max_headers_size(struct evhttp* http, ev_ssize_t max_headers_size); +/** XXX Document. */ +EVENT2_EXPORT_SYMBOL +void evhttp_set_max_body_size(struct evhttp* http, ev_ssize_t max_body_size); + +/** + Set the value to use for the Content-Type header when none was provided. If + the content type string is NULL, the Content-Type header will not be + automatically added. + + @param http the http server on which to set the default content type + @param content_type the value for the Content-Type header +*/ +EVENT2_EXPORT_SYMBOL +void evhttp_set_default_content_type(struct evhttp *http, + const char *content_type); + +/** + Sets the what HTTP methods are supported in requests accepted by this + server, and passed to user callbacks. + + If not supported they will generate a "405 Method not allowed" response. + + By default this includes the following methods: GET, POST, HEAD, PUT, DELETE + + @param http the http server on which to set the methods + @param methods bit mask constructed from evhttp_cmd_type values +*/ +EVENT2_EXPORT_SYMBOL +void evhttp_set_allowed_methods(struct evhttp* http, ev_uint16_t methods); + +/** + Set a callback for a specified URI + + @param http the http sever on which to set the callback + @param path the path for which to invoke the callback + @param cb the callback function that gets invoked on requesting path + @param cb_arg an additional context argument for the callback + @return 0 on success, -1 if the callback existed already, -2 on failure +*/ +EVENT2_EXPORT_SYMBOL +int evhttp_set_cb(struct evhttp *http, const char *path, + void (*cb)(struct evhttp_request *, void *), void *cb_arg); + +/** Removes the callback for a specified URI */ +EVENT2_EXPORT_SYMBOL +int evhttp_del_cb(struct evhttp *, const char *); + +/** + Set a callback for all requests that are not caught by specific callbacks + + Invokes the specified callback for all requests that do not match any of + the previously specified request paths. This is catchall for requests not + specifically configured with evhttp_set_cb(). + + @param http the evhttp server object for which to set the callback + @param cb the callback to invoke for any unmatched requests + @param arg an context argument for the callback +*/ +EVENT2_EXPORT_SYMBOL +void evhttp_set_gencb(struct evhttp *http, + void (*cb)(struct evhttp_request *, void *), void *arg); + +/** + Set a callback used to create new bufferevents for connections + to a given evhttp object. + + You can use this to override the default bufferevent type -- for example, + to make this evhttp object use SSL bufferevents rather than unencrypted + ones. + + New bufferevents must be allocated with no fd set on them. + + @param http the evhttp server object for which to set the callback + @param cb the callback to invoke for incoming connections + @param arg an context argument for the callback + */ +EVENT2_EXPORT_SYMBOL +void evhttp_set_bevcb(struct evhttp *http, + struct bufferevent *(*cb)(struct event_base *, void *), void *arg); + +/** + Adds a virtual host to the http server. + + A virtual host is a newly initialized evhttp object that has request + callbacks set on it via evhttp_set_cb() or evhttp_set_gencb(). It + most not have any listing sockets associated with it. + + If the virtual host has not been removed by the time that evhttp_free() + is called on the main http server, it will be automatically freed, too. + + It is possible to have hierarchical vhosts. For example: A vhost + with the pattern *.example.com may have other vhosts with patterns + foo.example.com and bar.example.com associated with it. + + @param http the evhttp object to which to add a virtual host + @param pattern the glob pattern against which the hostname is matched. + The match is case insensitive and follows otherwise regular shell + matching. + @param vhost the virtual host to add the regular http server. + @return 0 on success, -1 on failure + @see evhttp_remove_virtual_host() +*/ +EVENT2_EXPORT_SYMBOL +int evhttp_add_virtual_host(struct evhttp* http, const char *pattern, + struct evhttp* vhost); + +/** + Removes a virtual host from the http server. + + @param http the evhttp object from which to remove the virtual host + @param vhost the virtual host to remove from the regular http server. + @return 0 on success, -1 on failure + @see evhttp_add_virtual_host() +*/ +EVENT2_EXPORT_SYMBOL +int evhttp_remove_virtual_host(struct evhttp* http, struct evhttp* vhost); + +/** + Add a server alias to an http object. The http object can be a virtual + host or the main server. + + @param http the evhttp object + @param alias the alias to add + @see evhttp_add_remove_alias() +*/ +EVENT2_EXPORT_SYMBOL +int evhttp_add_server_alias(struct evhttp *http, const char *alias); + +/** + Remove a server alias from an http object. + + @param http the evhttp object + @param alias the alias to remove + @see evhttp_add_server_alias() +*/ +EVENT2_EXPORT_SYMBOL +int evhttp_remove_server_alias(struct evhttp *http, const char *alias); + +/** + * Set the timeout for an HTTP request. + * + * @param http an evhttp object + * @param timeout_in_secs the timeout, in seconds + */ +EVENT2_EXPORT_SYMBOL +void evhttp_set_timeout(struct evhttp *http, int timeout_in_secs); + +/** + * Set the timeout for an HTTP request. + * + * @param http an evhttp object + * @param tv the timeout, or NULL + */ +EVENT2_EXPORT_SYMBOL +void evhttp_set_timeout_tv(struct evhttp *http, const struct timeval* tv); + +/* Read all the clients body, and only after this respond with an error if the + * clients body exceed max_body_size */ +#define EVHTTP_SERVER_LINGERING_CLOSE 0x0001 +/** + * Set connection flags for HTTP server. + * + * @see EVHTTP_SERVER_* + * @return 0 on success, otherwise non zero (for example if flag doesn't + * supported). + */ +EVENT2_EXPORT_SYMBOL +int evhttp_set_flags(struct evhttp *http, int flags); + +/* Request/Response functionality */ + +/** + * Send an HTML error message to the client. + * + * @param req a request object + * @param error the HTTP error code + * @param reason a brief explanation of the error. If this is NULL, we'll + * just use the standard meaning of the error code. + */ +EVENT2_EXPORT_SYMBOL +void evhttp_send_error(struct evhttp_request *req, int error, + const char *reason); + +/** + * Send an HTML reply to the client. + * + * The body of the reply consists of the data in databuf. After calling + * evhttp_send_reply() databuf will be empty, but the buffer is still + * owned by the caller and needs to be deallocated by the caller if + * necessary. + * + * @param req a request object + * @param code the HTTP response code to send + * @param reason a brief message to send with the response code + * @param databuf the body of the response + */ +EVENT2_EXPORT_SYMBOL +void evhttp_send_reply(struct evhttp_request *req, int code, + const char *reason, struct evbuffer *databuf); + +/* Low-level response interface, for streaming/chunked replies */ + +/** + Initiate a reply that uses Transfer-Encoding chunked. + + This allows the caller to stream the reply back to the client and is + useful when either not all of the reply data is immediately available + or when sending very large replies. + + The caller needs to supply data chunks with evhttp_send_reply_chunk() + and complete the reply by calling evhttp_send_reply_end(). + + @param req a request object + @param code the HTTP response code to send + @param reason a brief message to send with the response code +*/ +EVENT2_EXPORT_SYMBOL +void evhttp_send_reply_start(struct evhttp_request *req, int code, + const char *reason); + +/** + Send another data chunk as part of an ongoing chunked reply. + + The reply chunk consists of the data in databuf. After calling + evhttp_send_reply_chunk() databuf will be empty, but the buffer is + still owned by the caller and needs to be deallocated by the caller + if necessary. + + @param req a request object + @param databuf the data chunk to send as part of the reply. +*/ +EVENT2_EXPORT_SYMBOL +void evhttp_send_reply_chunk(struct evhttp_request *req, + struct evbuffer *databuf); + +/** + Send another data chunk as part of an ongoing chunked reply. + + The reply chunk consists of the data in databuf. After calling + evhttp_send_reply_chunk() databuf will be empty, but the buffer is + still owned by the caller and needs to be deallocated by the caller + if necessary. + + @param req a request object + @param databuf the data chunk to send as part of the reply. + @param cb callback funcion + @param call back's argument. +*/ +EVENT2_EXPORT_SYMBOL +void evhttp_send_reply_chunk_with_cb(struct evhttp_request *, struct evbuffer *, + void (*cb)(struct evhttp_connection *, void *), void *arg); + +/** + Complete a chunked reply, freeing the request as appropriate. + + @param req a request object +*/ +EVENT2_EXPORT_SYMBOL +void evhttp_send_reply_end(struct evhttp_request *req); + +/* + * Interfaces for making requests + */ + +/** The different request types supported by evhttp. These are as specified + * in RFC2616, except for PATCH which is specified by RFC5789. + * + * By default, only some of these methods are accepted and passed to user + * callbacks; use evhttp_set_allowed_methods() to change which methods + * are allowed. + */ +enum evhttp_cmd_type { + EVHTTP_REQ_GET = 1 << 0, + EVHTTP_REQ_POST = 1 << 1, + EVHTTP_REQ_HEAD = 1 << 2, + EVHTTP_REQ_PUT = 1 << 3, + EVHTTP_REQ_DELETE = 1 << 4, + EVHTTP_REQ_OPTIONS = 1 << 5, + EVHTTP_REQ_TRACE = 1 << 6, + EVHTTP_REQ_CONNECT = 1 << 7, + EVHTTP_REQ_PATCH = 1 << 8 +}; + +/** a request object can represent either a request or a reply */ +enum evhttp_request_kind { EVHTTP_REQUEST, EVHTTP_RESPONSE }; + +/** + * Create and return a connection object that can be used to for making HTTP + * requests. The connection object tries to resolve address and establish the + * connection when it is given an http request object. + * + * @param base the event_base to use for handling the connection + * @param dnsbase the dns_base to use for resolving host names; if not + * specified host name resolution will block. + * @param bev a bufferevent to use for connecting to the server; if NULL, a + * socket-based bufferevent will be created. This buffrevent will be freed + * when the connection closes. It must have no fd set on it. + * @param address the address to which to connect + * @param port the port to connect to + * @return an evhttp_connection object that can be used for making requests + */ +EVENT2_EXPORT_SYMBOL +struct evhttp_connection *evhttp_connection_base_bufferevent_new( + struct event_base *base, struct evdns_base *dnsbase, struct bufferevent* bev, const char *address, ev_uint16_t port); + +/** + * Return the bufferevent that an evhttp_connection is using. + */ +EVENT2_EXPORT_SYMBOL +struct bufferevent* evhttp_connection_get_bufferevent(struct evhttp_connection *evcon); + +/** + * Return the HTTP server associated with this connection, or NULL. + */ +EVENT2_EXPORT_SYMBOL +struct evhttp *evhttp_connection_get_server(struct evhttp_connection *evcon); + +/** + * Creates a new request object that needs to be filled in with the request + * parameters. The callback is executed when the request completed or an + * error occurred. + */ +EVENT2_EXPORT_SYMBOL +struct evhttp_request *evhttp_request_new( + void (*cb)(struct evhttp_request *, void *), void *arg); + +/** + * Enable delivery of chunks to requestor. + * @param cb will be called after every read of data with the same argument + * as the completion callback. Will never be called on an empty + * response. May drain the input buffer; it will be drained + * automatically on return. + */ +EVENT2_EXPORT_SYMBOL +void evhttp_request_set_chunked_cb(struct evhttp_request *, + void (*cb)(struct evhttp_request *, void *)); + +/** + * Register callback for additional parsing of request headers. + * @param cb will be called after receiving and parsing the full header. + * It allows analyzing the header and possibly closing the connection + * by returning a value < 0. + */ +EVENT2_EXPORT_SYMBOL +void evhttp_request_set_header_cb(struct evhttp_request *, + int (*cb)(struct evhttp_request *, void *)); + +/** + * The different error types supported by evhttp + * + * @see evhttp_request_set_error_cb() + */ +enum evhttp_request_error { + /** + * Timeout reached, also @see evhttp_connection_set_timeout() + */ + EVREQ_HTTP_TIMEOUT, + /** + * EOF reached + */ + EVREQ_HTTP_EOF, + /** + * Error while reading header, or invalid header + */ + EVREQ_HTTP_INVALID_HEADER, + /** + * Error encountered while reading or writing + */ + EVREQ_HTTP_BUFFER_ERROR, + /** + * The evhttp_cancel_request() called on this request. + */ + EVREQ_HTTP_REQUEST_CANCEL, + /** + * Body is greater then evhttp_connection_set_max_body_size() + */ + EVREQ_HTTP_DATA_TOO_LONG +}; +/** + * Set a callback for errors + * @see evhttp_request_error for error types. + * + * On error, both the error callback and the regular callback will be called, + * error callback is called before the regular callback. + **/ +EVENT2_EXPORT_SYMBOL +void evhttp_request_set_error_cb(struct evhttp_request *, + void (*)(enum evhttp_request_error, void *)); + +/** + * Set a callback to be called on request completion of evhttp_send_* function. + * + * The callback function will be called on the completion of the request after + * the output data has been written and before the evhttp_request object + * is destroyed. This can be useful for tracking resources associated with a + * request (ex: timing metrics). + * + * @param req a request object + * @param cb callback function that will be called on request completion + * @param cb_arg an additional context argument for the callback + */ +EVENT2_EXPORT_SYMBOL +void evhttp_request_set_on_complete_cb(struct evhttp_request *req, + void (*cb)(struct evhttp_request *, void *), void *cb_arg); + +/** Frees the request object and removes associated events. */ +EVENT2_EXPORT_SYMBOL +void evhttp_request_free(struct evhttp_request *req); + +/** + * Create and return a connection object that can be used to for making HTTP + * requests. The connection object tries to resolve address and establish the + * connection when it is given an http request object. + * + * @param base the event_base to use for handling the connection + * @param dnsbase the dns_base to use for resolving host names; if not + * specified host name resolution will block. + * @param address the address to which to connect + * @param port the port to connect to + * @return an evhttp_connection object that can be used for making requests + */ +EVENT2_EXPORT_SYMBOL +struct evhttp_connection *evhttp_connection_base_new( + struct event_base *base, struct evdns_base *dnsbase, + const char *address, ev_uint16_t port); + +/** + * Set family hint for DNS requests. + */ +EVENT2_EXPORT_SYMBOL +void evhttp_connection_set_family(struct evhttp_connection *evcon, + int family); + +/* reuse connection address on retry */ +#define EVHTTP_CON_REUSE_CONNECTED_ADDR 0x0008 +/* Try to read error, since server may already send and close + * connection, but if at that time we have some data to send then we + * can send get EPIPE and fail, while we can read that HTTP error. */ +#define EVHTTP_CON_READ_ON_WRITE_ERROR 0x0010 +/* @see EVHTTP_SERVER_LINGERING_CLOSE */ +#define EVHTTP_CON_LINGERING_CLOSE 0x0020 +/* Padding for public flags, @see EVHTTP_CON_* in http-internal.h */ +#define EVHTTP_CON_PUBLIC_FLAGS_END 0x100000 +/** + * Set connection flags. + * + * @see EVHTTP_CON_* + * @return 0 on success, otherwise non zero (for example if flag doesn't + * supported). + */ +EVENT2_EXPORT_SYMBOL +int evhttp_connection_set_flags(struct evhttp_connection *evcon, + int flags); + +/** Takes ownership of the request object + * + * Can be used in a request callback to keep onto the request until + * evhttp_request_free() is explicitly called by the user. + */ +EVENT2_EXPORT_SYMBOL +void evhttp_request_own(struct evhttp_request *req); + +/** Returns 1 if the request is owned by the user */ +EVENT2_EXPORT_SYMBOL +int evhttp_request_is_owned(struct evhttp_request *req); + +/** + * Returns the connection object associated with the request or NULL + * + * The user needs to either free the request explicitly or call + * evhttp_send_reply_end(). + */ +EVENT2_EXPORT_SYMBOL +struct evhttp_connection *evhttp_request_get_connection(struct evhttp_request *req); + +/** + * Returns the underlying event_base for this connection + */ +EVENT2_EXPORT_SYMBOL +struct event_base *evhttp_connection_get_base(struct evhttp_connection *req); + +EVENT2_EXPORT_SYMBOL +void evhttp_connection_set_max_headers_size(struct evhttp_connection *evcon, + ev_ssize_t new_max_headers_size); + +EVENT2_EXPORT_SYMBOL +void evhttp_connection_set_max_body_size(struct evhttp_connection* evcon, + ev_ssize_t new_max_body_size); + +/** Frees an http connection */ +EVENT2_EXPORT_SYMBOL +void evhttp_connection_free(struct evhttp_connection *evcon); + +/** Disowns a given connection object + * + * Can be used to tell libevent to free the connection object after + * the last request has completed or failed. + */ +EVENT2_EXPORT_SYMBOL +void evhttp_connection_free_on_completion(struct evhttp_connection *evcon); + +/** sets the ip address from which http connections are made */ +EVENT2_EXPORT_SYMBOL +void evhttp_connection_set_local_address(struct evhttp_connection *evcon, + const char *address); + +/** sets the local port from which http connections are made */ +EVENT2_EXPORT_SYMBOL +void evhttp_connection_set_local_port(struct evhttp_connection *evcon, + ev_uint16_t port); + +/** Sets the timeout in seconds for events related to this connection */ +EVENT2_EXPORT_SYMBOL +void evhttp_connection_set_timeout(struct evhttp_connection *evcon, + int timeout_in_secs); + +/** Sets the timeout for events related to this connection. Takes a struct + * timeval. */ +EVENT2_EXPORT_SYMBOL +void evhttp_connection_set_timeout_tv(struct evhttp_connection *evcon, + const struct timeval *tv); + +/** Sets the delay before retrying requests on this connection. This is only + * used if evhttp_connection_set_retries is used to make the number of retries + * at least one. Each retry after the first is twice as long as the one before + * it. */ +EVENT2_EXPORT_SYMBOL +void evhttp_connection_set_initial_retry_tv(struct evhttp_connection *evcon, + const struct timeval *tv); + +/** Sets the retry limit for this connection - -1 repeats indefinitely */ +EVENT2_EXPORT_SYMBOL +void evhttp_connection_set_retries(struct evhttp_connection *evcon, + int retry_max); + +/** Set a callback for connection close. */ +EVENT2_EXPORT_SYMBOL +void evhttp_connection_set_closecb(struct evhttp_connection *evcon, + void (*)(struct evhttp_connection *, void *), void *); + +/** Get the remote address and port associated with this connection. */ +EVENT2_EXPORT_SYMBOL +void evhttp_connection_get_peer(struct evhttp_connection *evcon, + char **address, ev_uint16_t *port); + +/** Get the remote address associated with this connection. + * extracted from getpeername() OR from nameserver. + * + * @return NULL if getpeername() return non success, + * or connection is not connected, + * otherwise it return pointer to struct sockaddr_storage */ +EVENT2_EXPORT_SYMBOL +const struct sockaddr* +evhttp_connection_get_addr(struct evhttp_connection *evcon); + +/** + Make an HTTP request over the specified connection. + + The connection gets ownership of the request. On failure, the + request object is no longer valid as it has been freed. + + @param evcon the evhttp_connection object over which to send the request + @param req the previously created and configured request object + @param type the request type EVHTTP_REQ_GET, EVHTTP_REQ_POST, etc. + @param uri the URI associated with the request + @return 0 on success, -1 on failure + @see evhttp_cancel_request() +*/ +EVENT2_EXPORT_SYMBOL +int evhttp_make_request(struct evhttp_connection *evcon, + struct evhttp_request *req, + enum evhttp_cmd_type type, const char *uri); + +/** + Cancels a pending HTTP request. + + Cancels an ongoing HTTP request. The callback associated with this request + is not executed and the request object is freed. If the request is + currently being processed, e.g. it is ongoing, the corresponding + evhttp_connection object is going to get reset. + + A request cannot be canceled if its callback has executed already. A request + may be canceled reentrantly from its chunked callback. + + @param req the evhttp_request to cancel; req becomes invalid after this call. +*/ +EVENT2_EXPORT_SYMBOL +void evhttp_cancel_request(struct evhttp_request *req); + +/** + * A structure to hold a parsed URI or Relative-Ref conforming to RFC3986. + */ +struct evhttp_uri; + +/** Returns the request URI */ +EVENT2_EXPORT_SYMBOL +const char *evhttp_request_get_uri(const struct evhttp_request *req); +/** Returns the request URI (parsed) */ +EVENT2_EXPORT_SYMBOL +const struct evhttp_uri *evhttp_request_get_evhttp_uri(const struct evhttp_request *req); +/** Returns the request command */ +EVENT2_EXPORT_SYMBOL +enum evhttp_cmd_type evhttp_request_get_command(const struct evhttp_request *req); + +EVENT2_EXPORT_SYMBOL +int evhttp_request_get_response_code(const struct evhttp_request *req); +EVENT2_EXPORT_SYMBOL +const char * evhttp_request_get_response_code_line(const struct evhttp_request *req); + +/** Returns the input headers */ +EVENT2_EXPORT_SYMBOL +struct evkeyvalq *evhttp_request_get_input_headers(struct evhttp_request *req); +/** Returns the output headers */ +EVENT2_EXPORT_SYMBOL +struct evkeyvalq *evhttp_request_get_output_headers(struct evhttp_request *req); +/** Returns the input buffer */ +EVENT2_EXPORT_SYMBOL +struct evbuffer *evhttp_request_get_input_buffer(struct evhttp_request *req); +/** Returns the output buffer */ +EVENT2_EXPORT_SYMBOL +struct evbuffer *evhttp_request_get_output_buffer(struct evhttp_request *req); +/** Returns the host associated with the request. If a client sends an absolute + URI, the host part of that is preferred. Otherwise, the input headers are + searched for a Host: header. NULL is returned if no absolute URI or Host: + header is provided. */ +EVENT2_EXPORT_SYMBOL +const char *evhttp_request_get_host(struct evhttp_request *req); + +/* Interfaces for dealing with HTTP headers */ + +/** + Finds the value belonging to a header. + + @param headers the evkeyvalq object in which to find the header + @param key the name of the header to find + @returns a pointer to the value for the header or NULL if the header + could not be found. + @see evhttp_add_header(), evhttp_remove_header() +*/ +EVENT2_EXPORT_SYMBOL +const char *evhttp_find_header(const struct evkeyvalq *headers, + const char *key); + +/** + Removes a header from a list of existing headers. + + @param headers the evkeyvalq object from which to remove a header + @param key the name of the header to remove + @returns 0 if the header was removed, -1 otherwise. + @see evhttp_find_header(), evhttp_add_header() +*/ +EVENT2_EXPORT_SYMBOL +int evhttp_remove_header(struct evkeyvalq *headers, const char *key); + +/** + Adds a header to a list of existing headers. + + @param headers the evkeyvalq object to which to add a header + @param key the name of the header + @param value the value belonging to the header + @returns 0 on success, -1 otherwise. + @see evhttp_find_header(), evhttp_clear_headers() +*/ +EVENT2_EXPORT_SYMBOL +int evhttp_add_header(struct evkeyvalq *headers, const char *key, const char *value); + +/** + Removes all headers from the header list. + + @param headers the evkeyvalq object from which to remove all headers +*/ +EVENT2_EXPORT_SYMBOL +void evhttp_clear_headers(struct evkeyvalq *headers); + +/* Miscellaneous utility functions */ + + +/** + Helper function to encode a string for inclusion in a URI. All + characters are replaced by their hex-escaped (%22) equivalents, + except for characters explicitly unreserved by RFC3986 -- that is, + ASCII alphanumeric characters, hyphen, dot, underscore, and tilde. + + The returned string must be freed by the caller. + + @param str an unencoded string + @return a newly allocated URI-encoded string or NULL on failure + */ +EVENT2_EXPORT_SYMBOL +char *evhttp_encode_uri(const char *str); + +/** + As evhttp_encode_uri, but if 'size' is nonnegative, treat the string + as being 'size' bytes long. This allows you to encode strings that + may contain 0-valued bytes. + + The returned string must be freed by the caller. + + @param str an unencoded string + @param size the length of the string to encode, or -1 if the string + is NUL-terminated + @param space_to_plus if true, space characters in 'str' are encoded + as +, not %20. + @return a newly allocate URI-encoded string, or NULL on failure. + */ +EVENT2_EXPORT_SYMBOL +char *evhttp_uriencode(const char *str, ev_ssize_t size, int space_to_plus); + +/** + Helper function to sort of decode a URI-encoded string. Unlike + evhttp_get_decoded_uri, it decodes all plus characters that appear + _after_ the first question mark character, but no plusses that occur + before. This is not a good way to decode URIs in whole or in part. + + The returned string must be freed by the caller + + @deprecated This function is deprecated; you probably want to use + evhttp_get_decoded_uri instead. + + @param uri an encoded URI + @return a newly allocated unencoded URI or NULL on failure + */ +EVENT2_EXPORT_SYMBOL +char *evhttp_decode_uri(const char *uri); + +/** + Helper function to decode a URI-escaped string or HTTP parameter. + + If 'decode_plus' is 1, then we decode the string as an HTTP parameter + value, and convert all plus ('+') characters to spaces. If + 'decode_plus' is 0, we leave all plus characters unchanged. + + The returned string must be freed by the caller. + + @param uri a URI-encode encoded URI + @param decode_plus determines whether we convert '+' to space. + @param size_out if size_out is not NULL, *size_out is set to the size of the + returned string + @return a newly allocated unencoded URI or NULL on failure + */ +EVENT2_EXPORT_SYMBOL +char *evhttp_uridecode(const char *uri, int decode_plus, + size_t *size_out); + +/** + Helper function to parse out arguments in a query. + + Parsing a URI like + + http://foo.com/?q=test&s=some+thing + + will result in two entries in the key value queue. + + The first entry is: key="q", value="test" + The second entry is: key="s", value="some thing" + + @deprecated This function is deprecated as of Libevent 2.0.9. Use + evhttp_uri_parse and evhttp_parse_query_str instead. + + @param uri the request URI + @param headers the head of the evkeyval queue + @return 0 on success, -1 on failure + */ +EVENT2_EXPORT_SYMBOL +int evhttp_parse_query(const char *uri, struct evkeyvalq *headers); + +/** + Helper function to parse out arguments from the query portion of an + HTTP URI. + + Parsing a query string like + + q=test&s=some+thing + + will result in two entries in the key value queue. + + The first entry is: key="q", value="test" + The second entry is: key="s", value="some thing" + + @param query_parse the query portion of the URI + @param headers the head of the evkeyval queue + @return 0 on success, -1 on failure + */ +EVENT2_EXPORT_SYMBOL +int evhttp_parse_query_str(const char *uri, struct evkeyvalq *headers); + +/** + * Escape HTML character entities in a string. + * + * Replaces <, >, ", ' and & with <, >, ", + * ' and & correspondingly. + * + * The returned string needs to be freed by the caller. + * + * @param html an unescaped HTML string + * @return an escaped HTML string or NULL on error + */ +EVENT2_EXPORT_SYMBOL +char *evhttp_htmlescape(const char *html); + +/** + * Return a new empty evhttp_uri with no fields set. + */ +EVENT2_EXPORT_SYMBOL +struct evhttp_uri *evhttp_uri_new(void); + +/** + * Changes the flags set on a given URI. See EVHTTP_URI_* for + * a list of flags. + **/ +EVENT2_EXPORT_SYMBOL +void evhttp_uri_set_flags(struct evhttp_uri *uri, unsigned flags); + +/** Return the scheme of an evhttp_uri, or NULL if there is no scheme has + * been set and the evhttp_uri contains a Relative-Ref. */ +EVENT2_EXPORT_SYMBOL +const char *evhttp_uri_get_scheme(const struct evhttp_uri *uri); +/** + * Return the userinfo part of an evhttp_uri, or NULL if it has no userinfo + * set. + */ +EVENT2_EXPORT_SYMBOL +const char *evhttp_uri_get_userinfo(const struct evhttp_uri *uri); +/** + * Return the host part of an evhttp_uri, or NULL if it has no host set. + * The host may either be a regular hostname (conforming to the RFC 3986 + * "regname" production), or an IPv4 address, or the empty string, or a + * bracketed IPv6 address, or a bracketed 'IP-Future' address. + * + * Note that having a NULL host means that the URI has no authority + * section, but having an empty-string host means that the URI has an + * authority section with no host part. For example, + * "mailto:user@example.com" has a host of NULL, but "file:///etc/motd" + * has a host of "". + */ +EVENT2_EXPORT_SYMBOL +const char *evhttp_uri_get_host(const struct evhttp_uri *uri); +/** Return the port part of an evhttp_uri, or -1 if there is no port set. */ +EVENT2_EXPORT_SYMBOL +int evhttp_uri_get_port(const struct evhttp_uri *uri); +/** Return the path part of an evhttp_uri, or NULL if it has no path set */ +EVENT2_EXPORT_SYMBOL +const char *evhttp_uri_get_path(const struct evhttp_uri *uri); +/** Return the query part of an evhttp_uri (excluding the leading "?"), or + * NULL if it has no query set */ +EVENT2_EXPORT_SYMBOL +const char *evhttp_uri_get_query(const struct evhttp_uri *uri); +/** Return the fragment part of an evhttp_uri (excluding the leading "#"), + * or NULL if it has no fragment set */ +EVENT2_EXPORT_SYMBOL +const char *evhttp_uri_get_fragment(const struct evhttp_uri *uri); + +/** Set the scheme of an evhttp_uri, or clear the scheme if scheme==NULL. + * Returns 0 on success, -1 if scheme is not well-formed. */ +EVENT2_EXPORT_SYMBOL +int evhttp_uri_set_scheme(struct evhttp_uri *uri, const char *scheme); +/** Set the userinfo of an evhttp_uri, or clear the userinfo if userinfo==NULL. + * Returns 0 on success, -1 if userinfo is not well-formed. */ +EVENT2_EXPORT_SYMBOL +int evhttp_uri_set_userinfo(struct evhttp_uri *uri, const char *userinfo); +/** Set the host of an evhttp_uri, or clear the host if host==NULL. + * Returns 0 on success, -1 if host is not well-formed. */ +EVENT2_EXPORT_SYMBOL +int evhttp_uri_set_host(struct evhttp_uri *uri, const char *host); +/** Set the port of an evhttp_uri, or clear the port if port==-1. + * Returns 0 on success, -1 if port is not well-formed. */ +EVENT2_EXPORT_SYMBOL +int evhttp_uri_set_port(struct evhttp_uri *uri, int port); +/** Set the path of an evhttp_uri, or clear the path if path==NULL. + * Returns 0 on success, -1 if path is not well-formed. */ +EVENT2_EXPORT_SYMBOL +int evhttp_uri_set_path(struct evhttp_uri *uri, const char *path); +/** Set the query of an evhttp_uri, or clear the query if query==NULL. + * The query should not include a leading "?". + * Returns 0 on success, -1 if query is not well-formed. */ +EVENT2_EXPORT_SYMBOL +int evhttp_uri_set_query(struct evhttp_uri *uri, const char *query); +/** Set the fragment of an evhttp_uri, or clear the fragment if fragment==NULL. + * The fragment should not include a leading "#". + * Returns 0 on success, -1 if fragment is not well-formed. */ +EVENT2_EXPORT_SYMBOL +int evhttp_uri_set_fragment(struct evhttp_uri *uri, const char *fragment); + +/** + * Helper function to parse a URI-Reference as specified by RFC3986. + * + * This function matches the URI-Reference production from RFC3986, + * which includes both URIs like + * + * scheme://[[userinfo]@]foo.com[:port]]/[path][?query][#fragment] + * + * and relative-refs like + * + * [path][?query][#fragment] + * + * Any optional elements portions not present in the original URI are + * left set to NULL in the resulting evhttp_uri. If no port is + * specified, the port is set to -1. + * + * Note that no decoding is performed on percent-escaped characters in + * the string; if you want to parse them, use evhttp_uridecode or + * evhttp_parse_query_str as appropriate. + * + * Note also that most URI schemes will have additional constraints that + * this function does not know about, and cannot check. For example, + * mailto://www.example.com/cgi-bin/fortune.pl is not a reasonable + * mailto url, http://www.example.com:99999/ is not a reasonable HTTP + * URL, and ftp:username@example.com is not a reasonable FTP URL. + * Nevertheless, all of these URLs conform to RFC3986, and this function + * accepts all of them as valid. + * + * @param source_uri the request URI + * @param flags Zero or more EVHTTP_URI_* flags to affect the behavior + * of the parser. + * @return uri container to hold parsed data, or NULL if there is error + * @see evhttp_uri_free() + */ +EVENT2_EXPORT_SYMBOL +struct evhttp_uri *evhttp_uri_parse_with_flags(const char *source_uri, + unsigned flags); + +/** Tolerate URIs that do not conform to RFC3986. + * + * Unfortunately, some HTTP clients generate URIs that, according to RFC3986, + * are not conformant URIs. If you need to support these URIs, you can + * do so by passing this flag to evhttp_uri_parse_with_flags. + * + * Currently, these changes are: + * <ul> + * <li> Nonconformant URIs are allowed to contain otherwise unreasonable + * characters in their path, query, and fragment components. + * </ul> + */ +#define EVHTTP_URI_NONCONFORMANT 0x01 + +/** Alias for evhttp_uri_parse_with_flags(source_uri, 0) */ +EVENT2_EXPORT_SYMBOL +struct evhttp_uri *evhttp_uri_parse(const char *source_uri); + +/** + * Free all memory allocated for a parsed uri. Only use this for URIs + * generated by evhttp_uri_parse. + * + * @param uri container with parsed data + * @see evhttp_uri_parse() + */ +EVENT2_EXPORT_SYMBOL +void evhttp_uri_free(struct evhttp_uri *uri); + +/** + * Join together the uri parts from parsed data to form a URI-Reference. + * + * Note that no escaping of reserved characters is done on the members + * of the evhttp_uri, so the generated string might not be a valid URI + * unless the members of evhttp_uri are themselves valid. + * + * @param uri container with parsed data + * @param buf destination buffer + * @param limit destination buffer size + * @return an joined uri as string or NULL on error + * @see evhttp_uri_parse() + */ +EVENT2_EXPORT_SYMBOL +char *evhttp_uri_join(struct evhttp_uri *uri, char *buf, size_t limit); + +#ifdef __cplusplus +} +#endif + +#endif /* EVENT2_HTTP_H_INCLUDED_ */ diff --git a/include/event2/http_compat.h b/include/event2/http_compat.h new file mode 100644 index 000000000000..43c2c43e46b5 --- /dev/null +++ b/include/event2/http_compat.h @@ -0,0 +1,90 @@ +/* + * Copyright (c) 2000-2007 Niels Provos <provos@citi.umich.edu> + * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#ifndef EVENT2_HTTP_COMPAT_H_INCLUDED_ +#define EVENT2_HTTP_COMPAT_H_INCLUDED_ + +/** @file event2/http_compat.h + + Potentially non-threadsafe versions of the functions in http.h: provided + only for backwards compatibility. + + */ + +#ifdef __cplusplus +extern "C" { +#endif + +#include <event2/event-config.h> +#ifdef EVENT__HAVE_SYS_TYPES_H +#include <sys/types.h> +#endif +#ifdef EVENT__HAVE_SYS_TIME_H +#include <sys/time.h> +#endif + +/* For int types. */ +#include <event2/util.h> + +/** + * Start an HTTP server on the specified address and port + * + * @deprecated It does not allow an event base to be specified + * + * @param address the address to which the HTTP server should be bound + * @param port the port number on which the HTTP server should listen + * @return an struct evhttp object + */ +struct evhttp *evhttp_start(const char *address, ev_uint16_t port); + +/** + * A connection object that can be used to for making HTTP requests. The + * connection object tries to establish the connection when it is given an + * http request object. + * + * @deprecated It does not allow an event base to be specified + */ +struct evhttp_connection *evhttp_connection_new( + const char *address, ev_uint16_t port); + +/** + * Associates an event base with the connection - can only be called + * on a freshly created connection object that has not been used yet. + * + * @deprecated XXXX Why? + */ +void evhttp_connection_set_base(struct evhttp_connection *evcon, + struct event_base *base); + + +/** Returns the request URI */ +#define evhttp_request_uri evhttp_request_get_uri + +#ifdef __cplusplus +} +#endif + +#endif /* EVENT2_EVENT_COMPAT_H_INCLUDED_ */ diff --git a/include/event2/http_struct.h b/include/event2/http_struct.h new file mode 100644 index 000000000000..4bf5b1ff60f5 --- /dev/null +++ b/include/event2/http_struct.h @@ -0,0 +1,152 @@ +/* + * Copyright (c) 2000-2007 Niels Provos <provos@citi.umich.edu> + * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#ifndef EVENT2_HTTP_STRUCT_H_INCLUDED_ +#define EVENT2_HTTP_STRUCT_H_INCLUDED_ + +/** @file event2/http_struct.h + + Data structures for http. Using these structures may hurt forward + compatibility with later versions of Libevent: be careful! + + */ + +#ifdef __cplusplus +extern "C" { +#endif + +#include <event2/event-config.h> +#ifdef EVENT__HAVE_SYS_TYPES_H +#include <sys/types.h> +#endif +#ifdef EVENT__HAVE_SYS_TIME_H +#include <sys/time.h> +#endif + +/* For int types. */ +#include <event2/util.h> + +/** + * the request structure that a server receives. + * WARNING: expect this structure to change. I will try to provide + * reasonable accessors. + */ +struct evhttp_request { +#if defined(TAILQ_ENTRY) + TAILQ_ENTRY(evhttp_request) next; +#else +struct { + struct evhttp_request *tqe_next; + struct evhttp_request **tqe_prev; +} next; +#endif + + /* the connection object that this request belongs to */ + struct evhttp_connection *evcon; + int flags; +/** The request obj owns the evhttp connection and needs to free it */ +#define EVHTTP_REQ_OWN_CONNECTION 0x0001 +/** Request was made via a proxy */ +#define EVHTTP_PROXY_REQUEST 0x0002 +/** The request object is owned by the user; the user must free it */ +#define EVHTTP_USER_OWNED 0x0004 +/** The request will be used again upstack; freeing must be deferred */ +#define EVHTTP_REQ_DEFER_FREE 0x0008 +/** The request should be freed upstack */ +#define EVHTTP_REQ_NEEDS_FREE 0x0010 + + struct evkeyvalq *input_headers; + struct evkeyvalq *output_headers; + + /* address of the remote host and the port connection came from */ + char *remote_host; + ev_uint16_t remote_port; + + /* cache of the hostname for evhttp_request_get_host */ + char *host_cache; + + enum evhttp_request_kind kind; + enum evhttp_cmd_type type; + + size_t headers_size; + size_t body_size; + + char *uri; /* uri after HTTP request was parsed */ + struct evhttp_uri *uri_elems; /* uri elements */ + + char major; /* HTTP Major number */ + char minor; /* HTTP Minor number */ + + int response_code; /* HTTP Response code */ + char *response_code_line; /* Readable response */ + + struct evbuffer *input_buffer; /* read data */ + ev_int64_t ntoread; + unsigned chunked:1, /* a chunked request */ + userdone:1; /* the user has sent all data */ + + struct evbuffer *output_buffer; /* outgoing post or data */ + + /* Callback */ + void (*cb)(struct evhttp_request *, void *); + void *cb_arg; + + /* + * Chunked data callback - call for each completed chunk if + * specified. If not specified, all the data is delivered via + * the regular callback. + */ + void (*chunk_cb)(struct evhttp_request *, void *); + + /* + * Callback added for forked-daapd so they can collect ICY + * (shoutcast) metadata from the http header. If return + * int is negative the connection will be closed. + */ + int (*header_cb)(struct evhttp_request *, void *); + + /* + * Error callback - called when error is occured. + * @see evhttp_request_error for error types. + * + * @see evhttp_request_set_error_cb() + */ + void (*error_cb)(enum evhttp_request_error, void *); + + /* + * Send complete callback - called when the request is actually + * sent and completed. + */ + void (*on_complete_cb)(struct evhttp_request *, void *); + void *on_complete_cb_arg; +}; + +#ifdef __cplusplus +} +#endif + +#endif /* EVENT2_HTTP_STRUCT_H_INCLUDED_ */ + diff --git a/include/event2/keyvalq_struct.h b/include/event2/keyvalq_struct.h new file mode 100644 index 000000000000..bffa54b3a766 --- /dev/null +++ b/include/event2/keyvalq_struct.h @@ -0,0 +1,80 @@ +/* + * Copyright (c) 2000-2007 Niels Provos <provos@citi.umich.edu> + * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#ifndef EVENT2_KEYVALQ_STRUCT_H_INCLUDED_ +#define EVENT2_KEYVALQ_STRUCT_H_INCLUDED_ + +#ifdef __cplusplus +extern "C" { +#endif + +/* Fix so that people don't have to run with <sys/queue.h> */ +/* XXXX This code is duplicated with event_struct.h */ +#ifndef TAILQ_ENTRY +#define EVENT_DEFINED_TQENTRY_ +#define TAILQ_ENTRY(type) \ +struct { \ + struct type *tqe_next; /* next element */ \ + struct type **tqe_prev; /* address of previous next element */ \ +} +#endif /* !TAILQ_ENTRY */ + +#ifndef TAILQ_HEAD +#define EVENT_DEFINED_TQHEAD_ +#define TAILQ_HEAD(name, type) \ +struct name { \ + struct type *tqh_first; \ + struct type **tqh_last; \ +} +#endif + +/* + * Key-Value pairs. Can be used for HTTP headers but also for + * query argument parsing. + */ +struct evkeyval { + TAILQ_ENTRY(evkeyval) next; + + char *key; + char *value; +}; + +TAILQ_HEAD (evkeyvalq, evkeyval); + +/* XXXX This code is duplicated with event_struct.h */ +#ifdef EVENT_DEFINED_TQENTRY_ +#undef TAILQ_ENTRY +#endif + +#ifdef EVENT_DEFINED_TQHEAD_ +#undef TAILQ_HEAD +#endif + +#ifdef __cplusplus +} +#endif + +#endif diff --git a/include/event2/listener.h b/include/event2/listener.h new file mode 100644 index 000000000000..84b4da055d8d --- /dev/null +++ b/include/event2/listener.h @@ -0,0 +1,180 @@ +/* + * Copyright (c) 2000-2007 Niels Provos <provos@citi.umich.edu> + * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#ifndef EVENT2_LISTENER_H_INCLUDED_ +#define EVENT2_LISTENER_H_INCLUDED_ + +#include <event2/visibility.h> + +#ifdef __cplusplus +extern "C" { +#endif + +#include <event2/event.h> + +struct sockaddr; +struct evconnlistener; + +/** + A callback that we invoke when a listener has a new connection. + + @param listener The evconnlistener + @param fd The new file descriptor + @param addr The source address of the connection + @param socklen The length of addr + @param user_arg the pointer passed to evconnlistener_new() + */ +typedef void (*evconnlistener_cb)(struct evconnlistener *, evutil_socket_t, struct sockaddr *, int socklen, void *); + +/** + A callback that we invoke when a listener encounters a non-retriable error. + + @param listener The evconnlistener + @param user_arg the pointer passed to evconnlistener_new() + */ +typedef void (*evconnlistener_errorcb)(struct evconnlistener *, void *); + +/** Flag: Indicates that we should not make incoming sockets nonblocking + * before passing them to the callback. */ +#define LEV_OPT_LEAVE_SOCKETS_BLOCKING (1u<<0) +/** Flag: Indicates that freeing the listener should close the underlying + * socket. */ +#define LEV_OPT_CLOSE_ON_FREE (1u<<1) +/** Flag: Indicates that we should set the close-on-exec flag, if possible */ +#define LEV_OPT_CLOSE_ON_EXEC (1u<<2) +/** Flag: Indicates that we should disable the timeout (if any) between when + * this socket is closed and when we can listen again on the same port. */ +#define LEV_OPT_REUSEABLE (1u<<3) +/** Flag: Indicates that the listener should be locked so it's safe to use + * from multiple threadcs at once. */ +#define LEV_OPT_THREADSAFE (1u<<4) +/** Flag: Indicates that the listener should be created in disabled + * state. Use evconnlistener_enable() to enable it later. */ +#define LEV_OPT_DISABLED (1u<<5) +/** Flag: Indicates that the listener should defer accept() until data is + * available, if possible. Ignored on platforms that do not support this. + * + * This option can help performance for protocols where the client transmits + * immediately after connecting. Do not use this option if your protocol + * _doesn't_ start out with the client transmitting data, since in that case + * this option will sometimes cause the kernel to never tell you about the + * connection. + * + * This option is only supported by evconnlistener_new_bind(): it can't + * work with evconnlistener_new_fd(), since the listener needs to be told + * to use the option before it is actually bound. + */ +#define LEV_OPT_DEFERRED_ACCEPT (1u<<6) +/** Flag: Indicates that we ask to allow multiple servers (processes or + * threads) to bind to the same port if they each set the option. + * + * SO_REUSEPORT is what most people would expect SO_REUSEADDR to be, however + * SO_REUSEPORT does not imply SO_REUSEADDR. + * + * This is only available on Linux and kernel 3.9+ + */ +#define LEV_OPT_REUSEABLE_PORT (1u<<7) + +/** + Allocate a new evconnlistener object to listen for incoming TCP connections + on a given file descriptor. + + @param base The event base to associate the listener with. + @param cb A callback to be invoked when a new connection arrives. If the + callback is NULL, the listener will be treated as disabled until the + callback is set. + @param ptr A user-supplied pointer to give to the callback. + @param flags Any number of LEV_OPT_* flags + @param backlog Passed to the listen() call to determine the length of the + acceptable connection backlog. Set to -1 for a reasonable default. + Set to 0 if the socket is already listening. + @param fd The file descriptor to listen on. It must be a nonblocking + file descriptor, and it should already be bound to an appropriate + port and address. +*/ +EVENT2_EXPORT_SYMBOL +struct evconnlistener *evconnlistener_new(struct event_base *base, + evconnlistener_cb cb, void *ptr, unsigned flags, int backlog, + evutil_socket_t fd); +/** + Allocate a new evconnlistener object to listen for incoming TCP connections + on a given address. + + @param base The event base to associate the listener with. + @param cb A callback to be invoked when a new connection arrives. If the + callback is NULL, the listener will be treated as disabled until the + callback is set. + @param ptr A user-supplied pointer to give to the callback. + @param flags Any number of LEV_OPT_* flags + @param backlog Passed to the listen() call to determine the length of the + acceptable connection backlog. Set to -1 for a reasonable default. + @param addr The address to listen for connections on. + @param socklen The length of the address. + */ +EVENT2_EXPORT_SYMBOL +struct evconnlistener *evconnlistener_new_bind(struct event_base *base, + evconnlistener_cb cb, void *ptr, unsigned flags, int backlog, + const struct sockaddr *sa, int socklen); +/** + Disable and deallocate an evconnlistener. + */ +EVENT2_EXPORT_SYMBOL +void evconnlistener_free(struct evconnlistener *lev); +/** + Re-enable an evconnlistener that has been disabled. + */ +EVENT2_EXPORT_SYMBOL +int evconnlistener_enable(struct evconnlistener *lev); +/** + Stop listening for connections on an evconnlistener. + */ +EVENT2_EXPORT_SYMBOL +int evconnlistener_disable(struct evconnlistener *lev); + +/** Return an evconnlistener's associated event_base. */ +EVENT2_EXPORT_SYMBOL +struct event_base *evconnlistener_get_base(struct evconnlistener *lev); + +/** Return the socket that an evconnlistner is listening on. */ +EVENT2_EXPORT_SYMBOL +evutil_socket_t evconnlistener_get_fd(struct evconnlistener *lev); + +/** Change the callback on the listener to cb and its user_data to arg. + */ +EVENT2_EXPORT_SYMBOL +void evconnlistener_set_cb(struct evconnlistener *lev, + evconnlistener_cb cb, void *arg); + +/** Set an evconnlistener's error callback. */ +EVENT2_EXPORT_SYMBOL +void evconnlistener_set_error_cb(struct evconnlistener *lev, + evconnlistener_errorcb errorcb); + +#ifdef __cplusplus +} +#endif + +#endif diff --git a/include/event2/rpc.h b/include/event2/rpc.h new file mode 100644 index 000000000000..dd43df266a17 --- /dev/null +++ b/include/event2/rpc.h @@ -0,0 +1,596 @@ +/* + * Copyright (c) 2006-2007 Niels Provos <provos@citi.umich.edu> + * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#ifndef EVENT2_RPC_H_INCLUDED_ +#define EVENT2_RPC_H_INCLUDED_ + +#ifdef __cplusplus +extern "C" { +#endif + +/** @file rpc.h + * + * This header files provides basic support for an RPC server and client. + * + * To support RPCs in a server, every supported RPC command needs to be + * defined and registered. + * + * EVRPC_HEADER(SendCommand, Request, Reply); + * + * SendCommand is the name of the RPC command. + * Request is the name of a structure generated by event_rpcgen.py. + * It contains all parameters relating to the SendCommand RPC. The + * server needs to fill in the Reply structure. + * Reply is the name of a structure generated by event_rpcgen.py. It + * contains the answer to the RPC. + * + * To register an RPC with an HTTP server, you need to first create an RPC + * base with: + * + * struct evrpc_base *base = evrpc_init(http); + * + * A specific RPC can then be registered with + * + * EVRPC_REGISTER(base, SendCommand, Request, Reply, FunctionCB, arg); + * + * when the server receives an appropriately formatted RPC, the user callback + * is invoked. The callback needs to fill in the reply structure. + * + * void FunctionCB(EVRPC_STRUCT(SendCommand)* rpc, void *arg); + * + * To send the reply, call EVRPC_REQUEST_DONE(rpc); + * + * See the regression test for an example. + */ + +/** + Determines if the member has been set in the message + + @param msg the message to inspect + @param member the member variable to test for presences + @return 1 if it's present or 0 otherwise. +*/ +#define EVTAG_HAS(msg, member) \ + ((msg)->member##_set == 1) + +#ifndef EVENT2_RPC_COMPAT_H_INCLUDED_ + +/** + Assigns a value to the member in the message. + + @param msg the message to which to assign a value + @param member the name of the member variable + @param value the value to assign +*/ +#define EVTAG_ASSIGN(msg, member, value) \ + (*(msg)->base->member##_assign)((msg), (value)) +/** + Assigns a value to the member in the message. + + @param msg the message to which to assign a value + @param member the name of the member variable + @param value the value to assign + @param len the length of the value +*/ +#define EVTAG_ASSIGN_WITH_LEN(msg, member, value, len) \ + (*(msg)->base->member##_assign)((msg), (value), (len)) +/** + Returns the value for a member. + + @param msg the message from which to get the value + @param member the name of the member variable + @param pvalue a pointer to the variable to hold the value + @return 0 on success, -1 otherwise. +*/ +#define EVTAG_GET(msg, member, pvalue) \ + (*(msg)->base->member##_get)((msg), (pvalue)) +/** + Returns the value for a member. + + @param msg the message from which to get the value + @param member the name of the member variable + @param pvalue a pointer to the variable to hold the value + @param plen a pointer to the length of the value + @return 0 on success, -1 otherwise. +*/ +#define EVTAG_GET_WITH_LEN(msg, member, pvalue, plen) \ + (*(msg)->base->member##_get)((msg), (pvalue), (plen)) + +#endif /* EVENT2_RPC_COMPAT_H_INCLUDED_ */ + +/** + Adds a value to an array. +*/ +#define EVTAG_ARRAY_ADD_VALUE(msg, member, value) \ + (*(msg)->base->member##_add)((msg), (value)) +/** + Allocates a new entry in the array and returns it. +*/ +#define EVTAG_ARRAY_ADD(msg, member) \ + (*(msg)->base->member##_add)(msg) +/** + Gets a variable at the specified offset from the array. +*/ +#define EVTAG_ARRAY_GET(msg, member, offset, pvalue) \ + (*(msg)->base->member##_get)((msg), (offset), (pvalue)) +/** + Returns the number of entries in the array. +*/ +#define EVTAG_ARRAY_LEN(msg, member) ((msg)->member##_length) + + +struct evbuffer; +struct event_base; +struct evrpc_req_generic; +struct evrpc_request_wrapper; +struct evrpc; + +/** The type of a specific RPC Message + * + * @param rpcname the name of the RPC message + */ +#define EVRPC_STRUCT(rpcname) struct evrpc_req__##rpcname + +struct evhttp_request; +struct evrpc_status; +struct evrpc_hook_meta; + +/** Creates the definitions and prototypes for an RPC + * + * You need to use EVRPC_HEADER to create structures and function prototypes + * needed by the server and client implementation. The structures have to be + * defined in an .rpc file and converted to source code via event_rpcgen.py + * + * @param rpcname the name of the RPC + * @param reqstruct the name of the RPC request structure + * @param replystruct the name of the RPC reply structure + * @see EVRPC_GENERATE() + */ +#define EVRPC_HEADER(rpcname, reqstruct, rplystruct) \ +EVRPC_STRUCT(rpcname) { \ + struct evrpc_hook_meta *hook_meta; \ + struct reqstruct* request; \ + struct rplystruct* reply; \ + struct evrpc* rpc; \ + struct evhttp_request* http_req; \ + struct evbuffer* rpc_data; \ +}; \ +int evrpc_send_request_##rpcname(struct evrpc_pool *, \ + struct reqstruct *, struct rplystruct *, \ + void (*)(struct evrpc_status *, \ + struct reqstruct *, struct rplystruct *, void *cbarg), \ + void *); + +struct evrpc_pool; + +/** use EVRPC_GENERATE instead */ +struct evrpc_request_wrapper *evrpc_make_request_ctx( + struct evrpc_pool *pool, void *request, void *reply, + const char *rpcname, + void (*req_marshal)(struct evbuffer*, void *), + void (*rpl_clear)(void *), + int (*rpl_unmarshal)(void *, struct evbuffer *), + void (*cb)(struct evrpc_status *, void *, void *, void *), + void *cbarg); + +/** Creates a context structure that contains rpc specific information. + * + * EVRPC_MAKE_CTX is used to populate a RPC specific context that + * contains information about marshaling the RPC data types. + * + * @param rpcname the name of the RPC + * @param reqstruct the name of the RPC request structure + * @param replystruct the name of the RPC reply structure + * @param pool the evrpc_pool over which to make the request + * @param request a pointer to the RPC request structure object + * @param reply a pointer to the RPC reply structure object + * @param cb the callback function to call when the RPC has completed + * @param cbarg the argument to supply to the callback + */ +#define EVRPC_MAKE_CTX(rpcname, reqstruct, rplystruct, \ + pool, request, reply, cb, cbarg) \ + evrpc_make_request_ctx(pool, request, reply, \ + #rpcname, \ + (void (*)(struct evbuffer *, void *))reqstruct##_marshal, \ + (void (*)(void *))rplystruct##_clear, \ + (int (*)(void *, struct evbuffer *))rplystruct##_unmarshal, \ + (void (*)(struct evrpc_status *, void *, void *, void *))cb, \ + cbarg) + +/** Generates the code for receiving and sending an RPC message + * + * EVRPC_GENERATE is used to create the code corresponding to sending + * and receiving a particular RPC message + * + * @param rpcname the name of the RPC + * @param reqstruct the name of the RPC request structure + * @param replystruct the name of the RPC reply structure + * @see EVRPC_HEADER() + */ +#define EVRPC_GENERATE(rpcname, reqstruct, rplystruct) \ + int evrpc_send_request_##rpcname(struct evrpc_pool *pool, \ + struct reqstruct *request, struct rplystruct *reply, \ + void (*cb)(struct evrpc_status *, \ + struct reqstruct *, struct rplystruct *, void *cbarg), \ + void *cbarg) { \ + return evrpc_send_request_generic(pool, request, reply, \ + (void (*)(struct evrpc_status *, void *, void *, void *))cb, \ + cbarg, \ + #rpcname, \ + (void (*)(struct evbuffer *, void *))reqstruct##_marshal, \ + (void (*)(void *))rplystruct##_clear, \ + (int (*)(void *, struct evbuffer *))rplystruct##_unmarshal); \ +} + +/** Provides access to the HTTP request object underlying an RPC + * + * Access to the underlying http object; can be used to look at headers or + * for getting the remote ip address + * + * @param rpc_req the rpc request structure provided to the server callback + * @return an struct evhttp_request object that can be inspected for + * HTTP headers or sender information. + */ +#define EVRPC_REQUEST_HTTP(rpc_req) (rpc_req)->http_req + +/** completes the server response to an rpc request */ +void evrpc_request_done(struct evrpc_req_generic *req); + +/** accessors for request and reply */ +void *evrpc_get_request(struct evrpc_req_generic *req); +void *evrpc_get_reply(struct evrpc_req_generic *req); + +/** Creates the reply to an RPC request + * + * EVRPC_REQUEST_DONE is used to answer a request; the reply is expected + * to have been filled in. The request and reply pointers become invalid + * after this call has finished. + * + * @param rpc_req the rpc request structure provided to the server callback + */ +#define EVRPC_REQUEST_DONE(rpc_req) do { \ + struct evrpc_req_generic *req_ = (struct evrpc_req_generic *)(rpc_req); \ + evrpc_request_done(req_); \ +} while (0) + + +struct evrpc_base; +struct evhttp; + +/* functions to start up the rpc system */ + +/** Creates a new rpc base from which RPC requests can be received + * + * @param server a pointer to an existing HTTP server + * @return a newly allocated evrpc_base struct + * @see evrpc_free() + */ +struct evrpc_base *evrpc_init(struct evhttp *server); + +/** + * Frees the evrpc base + * + * For now, you are responsible for making sure that no rpcs are ongoing. + * + * @param base the evrpc_base object to be freed + * @see evrpc_init + */ +void evrpc_free(struct evrpc_base *base); + +/** register RPCs with the HTTP Server + * + * registers a new RPC with the HTTP server, each RPC needs to have + * a unique name under which it can be identified. + * + * @param base the evrpc_base structure in which the RPC should be + * registered. + * @param name the name of the RPC + * @param request the name of the RPC request structure + * @param reply the name of the RPC reply structure + * @param callback the callback that should be invoked when the RPC + * is received. The callback has the following prototype + * void (*callback)(EVRPC_STRUCT(Message)* rpc, void *arg) + * @param cbarg an additional parameter that can be passed to the callback. + * The parameter can be used to carry around state. + */ +#define EVRPC_REGISTER(base, name, request, reply, callback, cbarg) \ + evrpc_register_generic(base, #name, \ + (void (*)(struct evrpc_req_generic *, void *))callback, cbarg, \ + (void *(*)(void *))request##_new, NULL, \ + (void (*)(void *))request##_free, \ + (int (*)(void *, struct evbuffer *))request##_unmarshal, \ + (void *(*)(void *))reply##_new, NULL, \ + (void (*)(void *))reply##_free, \ + (int (*)(void *))reply##_complete, \ + (void (*)(struct evbuffer *, void *))reply##_marshal) + +/** + Low level function for registering an RPC with a server. + + Use EVRPC_REGISTER() instead. + + @see EVRPC_REGISTER() +*/ +int evrpc_register_rpc(struct evrpc_base *, struct evrpc *, + void (*)(struct evrpc_req_generic*, void *), void *); + +/** + * Unregisters an already registered RPC + * + * @param base the evrpc_base object from which to unregister an RPC + * @param name the name of the rpc to unregister + * @return -1 on error or 0 when successful. + * @see EVRPC_REGISTER() + */ +#define EVRPC_UNREGISTER(base, name) evrpc_unregister_rpc((base), #name) + +int evrpc_unregister_rpc(struct evrpc_base *base, const char *name); + +/* + * Client-side RPC support + */ + +struct evhttp_connection; +struct evrpc_status; + +/** launches an RPC and sends it to the server + * + * EVRPC_MAKE_REQUEST() is used by the client to send an RPC to the server. + * + * @param name the name of the RPC + * @param pool the evrpc_pool that contains the connection objects over which + * the request should be sent. + * @param request a pointer to the RPC request structure - it contains the + * data to be sent to the server. + * @param reply a pointer to the RPC reply structure. It is going to be filled + * if the request was answered successfully + * @param cb the callback to invoke when the RPC request has been answered + * @param cbarg an additional argument to be passed to the client + * @return 0 on success, -1 on failure + */ +#define EVRPC_MAKE_REQUEST(name, pool, request, reply, cb, cbarg) \ + evrpc_send_request_##name((pool), (request), (reply), (cb), (cbarg)) + +/** + Makes an RPC request based on the provided context. + + This is a low-level function and should not be used directly + unless a custom context object is provided. Use EVRPC_MAKE_REQUEST() + instead. + + @param ctx a context from EVRPC_MAKE_CTX() + @returns 0 on success, -1 otherwise. + @see EVRPC_MAKE_REQUEST(), EVRPC_MAKE_CTX() +*/ +int evrpc_make_request(struct evrpc_request_wrapper *ctx); + +/** creates an rpc connection pool + * + * a pool has a number of connections associated with it. + * rpc requests are always made via a pool. + * + * @param base a pointer to an struct event_based object; can be left NULL + * in singled-threaded applications + * @return a newly allocated struct evrpc_pool object + * @see evrpc_pool_free() + */ +struct evrpc_pool *evrpc_pool_new(struct event_base *base); +/** frees an rpc connection pool + * + * @param pool a pointer to an evrpc_pool allocated via evrpc_pool_new() + * @see evrpc_pool_new() + */ +void evrpc_pool_free(struct evrpc_pool *pool); + +/** + * Adds a connection over which rpc can be dispatched to the pool. + * + * The connection object must have been newly created. + * + * @param pool the pool to which to add the connection + * @param evcon the connection to add to the pool. + */ +void evrpc_pool_add_connection(struct evrpc_pool *pool, + struct evhttp_connection *evcon); + +/** + * Removes a connection from the pool. + * + * The connection object must have been newly created. + * + * @param pool the pool from which to remove the connection + * @param evcon the connection to remove from the pool. + */ +void evrpc_pool_remove_connection(struct evrpc_pool *pool, + struct evhttp_connection *evcon); + +/** + * Sets the timeout in secs after which a request has to complete. The + * RPC is completely aborted if it does not complete by then. Setting + * the timeout to 0 means that it never timeouts and can be used to + * implement callback type RPCs. + * + * Any connection already in the pool will be updated with the new + * timeout. Connections added to the pool after set_timeout has be + * called receive the pool timeout only if no timeout has been set + * for the connection itself. + * + * @param pool a pointer to a struct evrpc_pool object + * @param timeout_in_secs the number of seconds after which a request should + * timeout and a failure be returned to the callback. + */ +void evrpc_pool_set_timeout(struct evrpc_pool *pool, int timeout_in_secs); + +/** + * Hooks for changing the input and output of RPCs; this can be used to + * implement compression, authentication, encryption, ... + */ + +enum EVRPC_HOOK_TYPE { + EVRPC_INPUT, /**< apply the function to an input hook */ + EVRPC_OUTPUT /**< apply the function to an output hook */ +}; + +#ifndef _WIN32 +/** Deprecated alias for EVRPC_INPUT. Not available on windows, where it + * conflicts with platform headers. */ +#define INPUT EVRPC_INPUT +/** Deprecated alias for EVRPC_OUTPUT. Not available on windows, where it + * conflicts with platform headers. */ +#define OUTPUT EVRPC_OUTPUT +#endif + +/** + * Return value from hook processing functions + */ + +enum EVRPC_HOOK_RESULT { + EVRPC_TERMINATE = -1, /**< indicates the rpc should be terminated */ + EVRPC_CONTINUE = 0, /**< continue processing the rpc */ + EVRPC_PAUSE = 1 /**< pause processing request until resumed */ +}; + +/** adds a processing hook to either an rpc base or rpc pool + * + * If a hook returns TERMINATE, the processing is aborted. On CONTINUE, + * the request is immediately processed after the hook returns. If the + * hook returns PAUSE, request processing stops until evrpc_resume_request() + * has been called. + * + * The add functions return handles that can be used for removing hooks. + * + * @param vbase a pointer to either struct evrpc_base or struct evrpc_pool + * @param hook_type either INPUT or OUTPUT + * @param cb the callback to call when the hook is activated + * @param cb_arg an additional argument for the callback + * @return a handle to the hook so it can be removed later + * @see evrpc_remove_hook() + */ +void *evrpc_add_hook(void *vbase, + enum EVRPC_HOOK_TYPE hook_type, + int (*cb)(void *, struct evhttp_request *, struct evbuffer *, void *), + void *cb_arg); + +/** removes a previously added hook + * + * @param vbase a pointer to either struct evrpc_base or struct evrpc_pool + * @param hook_type either INPUT or OUTPUT + * @param handle a handle returned by evrpc_add_hook() + * @return 1 on success or 0 on failure + * @see evrpc_add_hook() + */ +int evrpc_remove_hook(void *vbase, + enum EVRPC_HOOK_TYPE hook_type, + void *handle); + +/** resume a paused request + * + * @param vbase a pointer to either struct evrpc_base or struct evrpc_pool + * @param ctx the context pointer provided to the original hook call + */ +int +evrpc_resume_request(void *vbase, void *ctx, enum EVRPC_HOOK_RESULT res); + +/** adds meta data to request + * + * evrpc_hook_add_meta() allows hooks to add meta data to a request. for + * a client request, the meta data can be inserted by an outgoing request hook + * and retrieved by the incoming request hook. + * + * @param ctx the context provided to the hook call + * @param key a NUL-terminated c-string + * @param data the data to be associated with the key + * @param data_size the size of the data + */ +void evrpc_hook_add_meta(void *ctx, const char *key, + const void *data, size_t data_size); + +/** retrieves meta data previously associated + * + * evrpc_hook_find_meta() can be used to retrieve meta data associated to a + * request by a previous hook. + * @param ctx the context provided to the hook call + * @param key a NUL-terminated c-string + * @param data pointer to a data pointer that will contain the retrieved data + * @param data_size pointer to the size of the data + * @return 0 on success or -1 on failure + */ +int evrpc_hook_find_meta(void *ctx, const char *key, + void **data, size_t *data_size); + +/** + * returns the connection object associated with the request + * + * @param ctx the context provided to the hook call + * @return a pointer to the evhttp_connection object + */ +struct evhttp_connection *evrpc_hook_get_connection(void *ctx); + +/** + Function for sending a generic RPC request. + + Do not call this function directly, use EVRPC_MAKE_REQUEST() instead. + + @see EVRPC_MAKE_REQUEST() + */ +int evrpc_send_request_generic(struct evrpc_pool *pool, + void *request, void *reply, + void (*cb)(struct evrpc_status *, void *, void *, void *), + void *cb_arg, + const char *rpcname, + void (*req_marshal)(struct evbuffer *, void *), + void (*rpl_clear)(void *), + int (*rpl_unmarshal)(void *, struct evbuffer *)); + +/** + Function for registering a generic RPC with the RPC base. + + Do not call this function directly, use EVRPC_REGISTER() instead. + + @see EVRPC_REGISTER() + */ +int +evrpc_register_generic(struct evrpc_base *base, const char *name, + void (*callback)(struct evrpc_req_generic *, void *), void *cbarg, + void *(*req_new)(void *), void *req_new_arg, void (*req_free)(void *), + int (*req_unmarshal)(void *, struct evbuffer *), + void *(*rpl_new)(void *), void *rpl_new_arg, void (*rpl_free)(void *), + int (*rpl_complete)(void *), + void (*rpl_marshal)(struct evbuffer *, void *)); + +/** accessors for obscure and undocumented functionality */ +struct evrpc_pool* evrpc_request_get_pool(struct evrpc_request_wrapper *ctx); +void evrpc_request_set_pool(struct evrpc_request_wrapper *ctx, + struct evrpc_pool *pool); +void evrpc_request_set_cb(struct evrpc_request_wrapper *ctx, + void (*cb)(struct evrpc_status*, void *request, void *reply, void *arg), + void *cb_arg); + +#ifdef __cplusplus +} +#endif + +#endif /* EVENT2_RPC_H_INCLUDED_ */ diff --git a/include/event2/rpc_compat.h b/include/event2/rpc_compat.h new file mode 100644 index 000000000000..8d8334d25f9d --- /dev/null +++ b/include/event2/rpc_compat.h @@ -0,0 +1,61 @@ +/* + * Copyright (c) 2006-2007 Niels Provos <provos@citi.umich.edu> + * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#ifndef EVENT2_RPC_COMPAT_H_INCLUDED_ +#define EVENT2_RPC_COMPAT_H_INCLUDED_ + +/** @file event2/rpc_compat.h + + Deprecated versions of the functions in rpc.h: provided only for + backwards compatibility. + + */ + +#ifdef __cplusplus +extern "C" { +#endif + +/** backwards compatible accessors that work only with gcc */ +#if defined(__GNUC__) && !defined(__STRICT_ANSI__) + +#undef EVTAG_ASSIGN +#undef EVTAG_GET +#undef EVTAG_ADD + +#define EVTAG_ASSIGN(msg, member, args...) \ + (*(msg)->base->member##_assign)(msg, ## args) +#define EVTAG_GET(msg, member, args...) \ + (*(msg)->base->member##_get)(msg, ## args) +#define EVTAG_ADD(msg, member, args...) \ + (*(msg)->base->member##_add)(msg, ## args) +#endif +#define EVTAG_LEN(msg, member) ((msg)->member##_length) + +#ifdef __cplusplus +} +#endif + +#endif /* EVENT2_EVENT_COMPAT_H_INCLUDED_ */ diff --git a/include/event2/rpc_struct.h b/include/event2/rpc_struct.h new file mode 100644 index 000000000000..8f691f49fbcd --- /dev/null +++ b/include/event2/rpc_struct.h @@ -0,0 +1,100 @@ +/* + * Copyright (c) 2006-2007 Niels Provos <provos@citi.umich.edu> + * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#ifndef EVENT2_RPC_STRUCT_H_INCLUDED_ +#define EVENT2_RPC_STRUCT_H_INCLUDED_ + +#ifdef __cplusplus +extern "C" { +#endif + +/** @file event2/rpc_struct.h + + Structures used by rpc.h. Using these structures directly may harm + forward compatibility: be careful! + + */ + +/** + * provides information about the completed RPC request. + */ +struct evrpc_status { +#define EVRPC_STATUS_ERR_NONE 0 +#define EVRPC_STATUS_ERR_TIMEOUT 1 +#define EVRPC_STATUS_ERR_BADPAYLOAD 2 +#define EVRPC_STATUS_ERR_UNSTARTED 3 +#define EVRPC_STATUS_ERR_HOOKABORTED 4 + int error; + + /* for looking at headers or other information */ + struct evhttp_request *http_req; +}; + +/* the structure below needs to be synchronized with evrpc_req_generic */ + +/* Encapsulates a request */ +struct evrpc { + TAILQ_ENTRY(evrpc) next; + + /* the URI at which the request handler lives */ + const char* uri; + + /* creates a new request structure */ + void *(*request_new)(void *); + void *request_new_arg; + + /* frees the request structure */ + void (*request_free)(void *); + + /* unmarshals the buffer into the proper request structure */ + int (*request_unmarshal)(void *, struct evbuffer *); + + /* creates a new reply structure */ + void *(*reply_new)(void *); + void *reply_new_arg; + + /* frees the reply structure */ + void (*reply_free)(void *); + + /* verifies that the reply is valid */ + int (*reply_complete)(void *); + + /* marshals the reply into a buffer */ + void (*reply_marshal)(struct evbuffer*, void *); + + /* the callback invoked for each received rpc */ + void (*cb)(struct evrpc_req_generic *, void *); + void *cb_arg; + + /* reference for further configuration */ + struct evrpc_base *base; +}; + +#ifdef __cplusplus +} +#endif + +#endif /* EVENT2_RPC_STRUCT_H_INCLUDED_ */ diff --git a/include/event2/tag.h b/include/event2/tag.h new file mode 100644 index 000000000000..2f73bfc00e93 --- /dev/null +++ b/include/event2/tag.h @@ -0,0 +1,146 @@ +/* + * Copyright (c) 2000-2007 Niels Provos <provos@citi.umich.edu> + * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#ifndef EVENT2_TAG_H_INCLUDED_ +#define EVENT2_TAG_H_INCLUDED_ + +/** @file event2/tag.h + + Helper functions for reading and writing tagged data onto buffers. + + */ + +#include <event2/visibility.h> + +#ifdef __cplusplus +extern "C" { +#endif + +#include <event2/event-config.h> +#ifdef EVENT__HAVE_SYS_TYPES_H +#include <sys/types.h> +#endif +#ifdef EVENT__HAVE_SYS_TIME_H +#include <sys/time.h> +#endif + +/* For int types. */ +#include <event2/util.h> + +struct evbuffer; + +/* + * Marshaling tagged data - We assume that all tags are inserted in their + * numeric order - so that unknown tags will always be higher than the + * known ones - and we can just ignore the end of an event buffer. + */ + +EVENT2_EXPORT_SYMBOL +void evtag_init(void); + +/** + Unmarshals the header and returns the length of the payload + + @param evbuf the buffer from which to unmarshal data + @param ptag a pointer in which the tag id is being stored + @returns -1 on failure or the number of bytes in the remaining payload. +*/ +EVENT2_EXPORT_SYMBOL +int evtag_unmarshal_header(struct evbuffer *evbuf, ev_uint32_t *ptag); + +EVENT2_EXPORT_SYMBOL +void evtag_marshal(struct evbuffer *evbuf, ev_uint32_t tag, const void *data, + ev_uint32_t len); +EVENT2_EXPORT_SYMBOL +void evtag_marshal_buffer(struct evbuffer *evbuf, ev_uint32_t tag, + struct evbuffer *data); + +/** + Encode an integer and store it in an evbuffer. + + We encode integers by nybbles; the first nibble contains the number + of significant nibbles - 1; this allows us to encode up to 64-bit + integers. This function is byte-order independent. + + @param evbuf evbuffer to store the encoded number + @param number a 32-bit integer + */ +EVENT2_EXPORT_SYMBOL +void evtag_encode_int(struct evbuffer *evbuf, ev_uint32_t number); +EVENT2_EXPORT_SYMBOL +void evtag_encode_int64(struct evbuffer *evbuf, ev_uint64_t number); + +EVENT2_EXPORT_SYMBOL +void evtag_marshal_int(struct evbuffer *evbuf, ev_uint32_t tag, + ev_uint32_t integer); +EVENT2_EXPORT_SYMBOL +void evtag_marshal_int64(struct evbuffer *evbuf, ev_uint32_t tag, + ev_uint64_t integer); + +EVENT2_EXPORT_SYMBOL +void evtag_marshal_string(struct evbuffer *buf, ev_uint32_t tag, + const char *string); + +EVENT2_EXPORT_SYMBOL +void evtag_marshal_timeval(struct evbuffer *evbuf, ev_uint32_t tag, + struct timeval *tv); + +EVENT2_EXPORT_SYMBOL +int evtag_unmarshal(struct evbuffer *src, ev_uint32_t *ptag, + struct evbuffer *dst); +EVENT2_EXPORT_SYMBOL +int evtag_peek(struct evbuffer *evbuf, ev_uint32_t *ptag); +EVENT2_EXPORT_SYMBOL +int evtag_peek_length(struct evbuffer *evbuf, ev_uint32_t *plength); +EVENT2_EXPORT_SYMBOL +int evtag_payload_length(struct evbuffer *evbuf, ev_uint32_t *plength); +EVENT2_EXPORT_SYMBOL +int evtag_consume(struct evbuffer *evbuf); + +EVENT2_EXPORT_SYMBOL +int evtag_unmarshal_int(struct evbuffer *evbuf, ev_uint32_t need_tag, + ev_uint32_t *pinteger); +EVENT2_EXPORT_SYMBOL +int evtag_unmarshal_int64(struct evbuffer *evbuf, ev_uint32_t need_tag, + ev_uint64_t *pinteger); + +EVENT2_EXPORT_SYMBOL +int evtag_unmarshal_fixed(struct evbuffer *src, ev_uint32_t need_tag, + void *data, size_t len); + +EVENT2_EXPORT_SYMBOL +int evtag_unmarshal_string(struct evbuffer *evbuf, ev_uint32_t need_tag, + char **pstring); + +EVENT2_EXPORT_SYMBOL +int evtag_unmarshal_timeval(struct evbuffer *evbuf, ev_uint32_t need_tag, + struct timeval *ptv); + +#ifdef __cplusplus +} +#endif + +#endif /* EVENT2_TAG_H_INCLUDED_ */ diff --git a/include/event2/tag_compat.h b/include/event2/tag_compat.h new file mode 100644 index 000000000000..a276c0d35b6e --- /dev/null +++ b/include/event2/tag_compat.h @@ -0,0 +1,49 @@ +/* + * Copyright (c) 2000-2007 Niels Provos <provos@citi.umich.edu> + * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#ifndef EVENT2_TAG_COMPAT_H_INCLUDED_ +#define EVENT2_TAG_COMPAT_H_INCLUDED_ + +/** @file event2/tag_compat.h + + Obsolete/deprecated functions from tag.h; provided only for backwards + compatibility. + */ + +/** + @name Misnamed functions + + @deprecated These macros are deprecated because their names don't follow + Libevent's naming conventions. Use evtag_encode_int and + evtag_encode_int64 instead. + + @{ +*/ +#define encode_int(evbuf, number) evtag_encode_int((evbuf), (number)) +#define encode_int64(evbuf, number) evtag_encode_int64((evbuf), (number)) +/**@}*/ + +#endif /* EVENT2_TAG_H_INCLUDED_ */ diff --git a/include/event2/thread.h b/include/event2/thread.h new file mode 100644 index 000000000000..b51998631b7a --- /dev/null +++ b/include/event2/thread.h @@ -0,0 +1,253 @@ +/* + * Copyright (c) 2008-2012 Niels Provos and Nick Mathewson + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#ifndef EVENT2_THREAD_H_INCLUDED_ +#define EVENT2_THREAD_H_INCLUDED_ + +/** @file event2/thread.h + + Functions for multi-threaded applications using Libevent. + + When using a multi-threaded application in which multiple threads + add and delete events from a single event base, Libevent needs to + lock its data structures. + + Like the memory-management function hooks, all of the threading functions + _must_ be set up before an event_base is created if you want the base to + use them. + + Most programs will either be using Windows threads or Posix threads. You + can configure Libevent to use one of these event_use_windows_threads() or + event_use_pthreads() respectively. If you're using another threading + library, you'll need to configure threading functions manually using + evthread_set_lock_callbacks() and evthread_set_condition_callbacks(). + + */ + +#include <event2/visibility.h> + +#ifdef __cplusplus +extern "C" { +#endif + +#include <event2/event-config.h> + +/** + @name Flags passed to lock functions + + @{ +*/ +/** A flag passed to a locking callback when the lock was allocated as a + * read-write lock, and we want to acquire or release the lock for writing. */ +#define EVTHREAD_WRITE 0x04 +/** A flag passed to a locking callback when the lock was allocated as a + * read-write lock, and we want to acquire or release the lock for reading. */ +#define EVTHREAD_READ 0x08 +/** A flag passed to a locking callback when we don't want to block waiting + * for the lock; if we can't get the lock immediately, we will instead + * return nonzero from the locking callback. */ +#define EVTHREAD_TRY 0x10 +/**@}*/ + +#if !defined(EVENT__DISABLE_THREAD_SUPPORT) || defined(EVENT_IN_DOXYGEN_) + +#define EVTHREAD_LOCK_API_VERSION 1 + +/** + @name Types of locks + + @{*/ +/** A recursive lock is one that can be acquired multiple times at once by the + * same thread. No other process can allocate the lock until the thread that + * has been holding it has unlocked it as many times as it locked it. */ +#define EVTHREAD_LOCKTYPE_RECURSIVE 1 +/* A read-write lock is one that allows multiple simultaneous readers, but + * where any one writer excludes all other writers and readers. */ +#define EVTHREAD_LOCKTYPE_READWRITE 2 +/**@}*/ + +/** This structure describes the interface a threading library uses for + * locking. It's used to tell evthread_set_lock_callbacks() how to use + * locking on this platform. + */ +struct evthread_lock_callbacks { + /** The current version of the locking API. Set this to + * EVTHREAD_LOCK_API_VERSION */ + int lock_api_version; + /** Which kinds of locks does this version of the locking API + * support? A bitfield of EVTHREAD_LOCKTYPE_RECURSIVE and + * EVTHREAD_LOCKTYPE_READWRITE. + * + * (Note that RECURSIVE locks are currently mandatory, and + * READWRITE locks are not currently used.) + **/ + unsigned supported_locktypes; + /** Function to allocate and initialize new lock of type 'locktype'. + * Returns NULL on failure. */ + void *(*alloc)(unsigned locktype); + /** Funtion to release all storage held in 'lock', which was created + * with type 'locktype'. */ + void (*free)(void *lock, unsigned locktype); + /** Acquire an already-allocated lock at 'lock' with mode 'mode'. + * Returns 0 on success, and nonzero on failure. */ + int (*lock)(unsigned mode, void *lock); + /** Release a lock at 'lock' using mode 'mode'. Returns 0 on success, + * and nonzero on failure. */ + int (*unlock)(unsigned mode, void *lock); +}; + +/** Sets a group of functions that Libevent should use for locking. + * For full information on the required callback API, see the + * documentation for the individual members of evthread_lock_callbacks. + * + * Note that if you're using Windows or the Pthreads threading library, you + * probably shouldn't call this function; instead, use + * evthread_use_windows_threads() or evthread_use_posix_threads() if you can. + */ +EVENT2_EXPORT_SYMBOL +int evthread_set_lock_callbacks(const struct evthread_lock_callbacks *); + +#define EVTHREAD_CONDITION_API_VERSION 1 + +struct timeval; + +/** This structure describes the interface a threading library uses for + * condition variables. It's used to tell evthread_set_condition_callbacks + * how to use locking on this platform. + */ +struct evthread_condition_callbacks { + /** The current version of the conditions API. Set this to + * EVTHREAD_CONDITION_API_VERSION */ + int condition_api_version; + /** Function to allocate and initialize a new condition variable. + * Returns the condition variable on success, and NULL on failure. + * The 'condtype' argument will be 0 with this API version. + */ + void *(*alloc_condition)(unsigned condtype); + /** Function to free a condition variable. */ + void (*free_condition)(void *cond); + /** Function to signal a condition variable. If 'broadcast' is 1, all + * threads waiting on 'cond' should be woken; otherwise, only on one + * thread is worken. Should return 0 on success, -1 on failure. + * This function will only be called while holding the associated + * lock for the condition. + */ + int (*signal_condition)(void *cond, int broadcast); + /** Function to wait for a condition variable. The lock 'lock' + * will be held when this function is called; should be released + * while waiting for the condition to be come signalled, and + * should be held again when this function returns. + * If timeout is provided, it is interval of seconds to wait for + * the event to become signalled; if it is NULL, the function + * should wait indefinitely. + * + * The function should return -1 on error; 0 if the condition + * was signalled, or 1 on a timeout. */ + int (*wait_condition)(void *cond, void *lock, + const struct timeval *timeout); +}; + +/** Sets a group of functions that Libevent should use for condition variables. + * For full information on the required callback API, see the + * documentation for the individual members of evthread_condition_callbacks. + * + * Note that if you're using Windows or the Pthreads threading library, you + * probably shouldn't call this function; instead, use + * evthread_use_windows_threads() or evthread_use_pthreads() if you can. + */ +EVENT2_EXPORT_SYMBOL +int evthread_set_condition_callbacks( + const struct evthread_condition_callbacks *); + +/** + Sets the function for determining the thread id. + + @param base the event base for which to set the id function + @param id_fn the identify function Libevent should invoke to + determine the identity of a thread. +*/ +EVENT2_EXPORT_SYMBOL +void evthread_set_id_callback( + unsigned long (*id_fn)(void)); + +#if (defined(_WIN32) && !defined(EVENT__DISABLE_THREAD_SUPPORT)) || defined(EVENT_IN_DOXYGEN_) +/** Sets up Libevent for use with Windows builtin locking and thread ID + functions. Unavailable if Libevent is not built for Windows. + + @return 0 on success, -1 on failure. */ +EVENT2_EXPORT_SYMBOL +int evthread_use_windows_threads(void); +/** + Defined if Libevent was built with support for evthread_use_windows_threads() +*/ +#define EVTHREAD_USE_WINDOWS_THREADS_IMPLEMENTED 1 +#endif + +#if defined(EVENT__HAVE_PTHREADS) || defined(EVENT_IN_DOXYGEN_) +/** Sets up Libevent for use with Pthreads locking and thread ID functions. + Unavailable if Libevent is not build for use with pthreads. Requires + libraries to link against Libevent_pthreads as well as Libevent. + + @return 0 on success, -1 on failure. */ +EVENT2_EXPORT_SYMBOL +int evthread_use_pthreads(void); +/** Defined if Libevent was built with support for evthread_use_pthreads() */ +#define EVTHREAD_USE_PTHREADS_IMPLEMENTED 1 + +#endif + +/** Enable debugging wrappers around the current lock callbacks. If Libevent + * makes one of several common locking errors, exit with an assertion failure. + * + * If you're going to call this function, you must do so before any locks are + * allocated. + **/ +EVENT2_EXPORT_SYMBOL +void evthread_enable_lock_debugging(void); + +/* Old (misspelled) version: This is deprecated; use + * evthread_enable_log_debugging instead. */ +EVENT2_EXPORT_SYMBOL +void evthread_enable_lock_debuging(void); + +#endif /* EVENT__DISABLE_THREAD_SUPPORT */ + +struct event_base; +/** Make sure it's safe to tell an event base to wake up from another thread + or a signal handler. + + You shouldn't need to call this by hand; configuring the base with thread + support should be necessary and sufficient. + + @return 0 on success, -1 on failure. + */ +EVENT2_EXPORT_SYMBOL +int evthread_make_base_notifiable(struct event_base *base); + +#ifdef __cplusplus +} +#endif + +#endif /* EVENT2_THREAD_H_INCLUDED_ */ diff --git a/include/event2/util.h b/include/event2/util.h new file mode 100644 index 000000000000..dd4bbb69d081 --- /dev/null +++ b/include/event2/util.h @@ -0,0 +1,866 @@ +/* + * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#ifndef EVENT2_UTIL_H_INCLUDED_ +#define EVENT2_UTIL_H_INCLUDED_ + +/** @file event2/util.h + + Common convenience functions for cross-platform portability and + related socket manipulations. + + */ +#include <event2/visibility.h> + +#ifdef __cplusplus +extern "C" { +#endif + +#include <event2/event-config.h> +#ifdef EVENT__HAVE_SYS_TIME_H +#include <sys/time.h> +#endif +#ifdef EVENT__HAVE_STDINT_H +#include <stdint.h> +#elif defined(EVENT__HAVE_INTTYPES_H) +#include <inttypes.h> +#endif +#ifdef EVENT__HAVE_SYS_TYPES_H +#include <sys/types.h> +#endif +#ifdef EVENT__HAVE_STDDEF_H +#include <stddef.h> +#endif +#ifdef _MSC_VER +#include <BaseTsd.h> +#endif +#include <stdarg.h> +#ifdef EVENT__HAVE_NETDB_H +#if !defined(_GNU_SOURCE) +#define _GNU_SOURCE +#endif +#include <netdb.h> +#endif + +#ifdef _WIN32 +#include <winsock2.h> +#ifdef EVENT__HAVE_GETADDRINFO +/* for EAI_* definitions. */ +#include <ws2tcpip.h> +#endif +#else +#ifdef EVENT__HAVE_ERRNO_H +#include <errno.h> +#endif +#include <sys/socket.h> +#endif + +#include <time.h> + +/* Some openbsd autoconf versions get the name of this macro wrong. */ +#if defined(EVENT__SIZEOF_VOID__) && !defined(EVENT__SIZEOF_VOID_P) +#define EVENT__SIZEOF_VOID_P EVENT__SIZEOF_VOID__ +#endif + +/** + * @name Standard integer types. + * + * Integer type definitions for types that are supposed to be defined in the + * C99-specified stdint.h. Shamefully, some platforms do not include + * stdint.h, so we need to replace it. (If you are on a platform like this, + * your C headers are now over 10 years out of date. You should bug them to + * do something about this.) + * + * We define: + * + * <dl> + * <dt>ev_uint64_t, ev_uint32_t, ev_uint16_t, ev_uint8_t</dt> + * <dd>unsigned integer types of exactly 64, 32, 16, and 8 bits + * respectively.</dd> + * <dt>ev_int64_t, ev_int32_t, ev_int16_t, ev_int8_t</dt> + * <dd>signed integer types of exactly 64, 32, 16, and 8 bits + * respectively.</dd> + * <dt>ev_uintptr_t, ev_intptr_t</dt> + * <dd>unsigned/signed integers large enough + * to hold a pointer without loss of bits.</dd> + * <dt>ev_ssize_t</dt> + * <dd>A signed type of the same size as size_t</dd> + * <dt>ev_off_t</dt> + * <dd>A signed type typically used to represent offsets within a + * (potentially large) file</dd> + * + * @{ + */ +#ifdef EVENT__HAVE_UINT64_T +#define ev_uint64_t uint64_t +#define ev_int64_t int64_t +#elif defined(_WIN32) +#define ev_uint64_t unsigned __int64 +#define ev_int64_t signed __int64 +#elif EVENT__SIZEOF_LONG_LONG == 8 +#define ev_uint64_t unsigned long long +#define ev_int64_t long long +#elif EVENT__SIZEOF_LONG == 8 +#define ev_uint64_t unsigned long +#define ev_int64_t long +#elif defined(EVENT_IN_DOXYGEN_) +#define ev_uint64_t ... +#define ev_int64_t ... +#else +#error "No way to define ev_uint64_t" +#endif + +#ifdef EVENT__HAVE_UINT32_T +#define ev_uint32_t uint32_t +#define ev_int32_t int32_t +#elif defined(_WIN32) +#define ev_uint32_t unsigned int +#define ev_int32_t signed int +#elif EVENT__SIZEOF_LONG == 4 +#define ev_uint32_t unsigned long +#define ev_int32_t signed long +#elif EVENT__SIZEOF_INT == 4 +#define ev_uint32_t unsigned int +#define ev_int32_t signed int +#elif defined(EVENT_IN_DOXYGEN_) +#define ev_uint32_t ... +#define ev_int32_t ... +#else +#error "No way to define ev_uint32_t" +#endif + +#ifdef EVENT__HAVE_UINT16_T +#define ev_uint16_t uint16_t +#define ev_int16_t int16_t +#elif defined(_WIN32) +#define ev_uint16_t unsigned short +#define ev_int16_t signed short +#elif EVENT__SIZEOF_INT == 2 +#define ev_uint16_t unsigned int +#define ev_int16_t signed int +#elif EVENT__SIZEOF_SHORT == 2 +#define ev_uint16_t unsigned short +#define ev_int16_t signed short +#elif defined(EVENT_IN_DOXYGEN_) +#define ev_uint16_t ... +#define ev_int16_t ... +#else +#error "No way to define ev_uint16_t" +#endif + +#ifdef EVENT__HAVE_UINT8_T +#define ev_uint8_t uint8_t +#define ev_int8_t int8_t +#elif defined(EVENT_IN_DOXYGEN_) +#define ev_uint8_t ... +#define ev_int8_t ... +#else +#define ev_uint8_t unsigned char +#define ev_int8_t signed char +#endif + +#ifdef EVENT__HAVE_UINTPTR_T +#define ev_uintptr_t uintptr_t +#define ev_intptr_t intptr_t +#elif EVENT__SIZEOF_VOID_P <= 4 +#define ev_uintptr_t ev_uint32_t +#define ev_intptr_t ev_int32_t +#elif EVENT__SIZEOF_VOID_P <= 8 +#define ev_uintptr_t ev_uint64_t +#define ev_intptr_t ev_int64_t +#elif defined(EVENT_IN_DOXYGEN_) +#define ev_uintptr_t ... +#define ev_intptr_t ... +#else +#error "No way to define ev_uintptr_t" +#endif + +#ifdef EVENT__ssize_t +#define ev_ssize_t EVENT__ssize_t +#else +#define ev_ssize_t ssize_t +#endif + +/* Note that we define ev_off_t based on the compile-time size of off_t that + * we used to build Libevent, and not based on the current size of off_t. + * (For example, we don't define ev_off_t to off_t.). We do this because + * some systems let you build your software with different off_t sizes + * at runtime, and so putting in any dependency on off_t would risk API + * mismatch. + */ +#ifdef _WIN32 +#define ev_off_t ev_int64_t +#elif EVENT__SIZEOF_OFF_T == 8 +#define ev_off_t ev_int64_t +#elif EVENT__SIZEOF_OFF_T == 4 +#define ev_off_t ev_int32_t +#elif defined(EVENT_IN_DOXYGEN_) +#define ev_off_t ... +#else +#define ev_off_t off_t +#endif +/**@}*/ + +/* Limits for integer types. + + We're making two assumptions here: + - The compiler does constant folding properly. + - The platform does signed arithmetic in two's complement. +*/ + +/** + @name Limits for integer types + + These macros hold the largest or smallest values possible for the + ev_[u]int*_t types. + + @{ +*/ +#ifndef EVENT__HAVE_STDINT_H +#define EV_UINT64_MAX ((((ev_uint64_t)0xffffffffUL) << 32) | 0xffffffffUL) +#define EV_INT64_MAX ((((ev_int64_t) 0x7fffffffL) << 32) | 0xffffffffL) +#define EV_INT64_MIN ((-EV_INT64_MAX) - 1) +#define EV_UINT32_MAX ((ev_uint32_t)0xffffffffUL) +#define EV_INT32_MAX ((ev_int32_t) 0x7fffffffL) +#define EV_INT32_MIN ((-EV_INT32_MAX) - 1) +#define EV_UINT16_MAX ((ev_uint16_t)0xffffUL) +#define EV_INT16_MAX ((ev_int16_t) 0x7fffL) +#define EV_INT16_MIN ((-EV_INT16_MAX) - 1) +#define EV_UINT8_MAX 255 +#define EV_INT8_MAX 127 +#define EV_INT8_MIN ((-EV_INT8_MAX) - 1) +#else +#define EV_UINT64_MAX UINT64_MAX +#define EV_INT64_MAX INT64_MAX +#define EV_INT64_MIN INT64_MIN +#define EV_UINT32_MAX UINT32_MAX +#define EV_INT32_MAX INT32_MAX +#define EV_INT32_MIN INT32_MIN +#define EV_UINT16_MAX UINT16_MAX +#define EV_INT16_MAX INT16_MAX +#define EV_UINT8_MAX UINT8_MAX +#define EV_INT8_MAX INT8_MAX +#define EV_INT8_MIN INT8_MIN +/** @} */ +#endif + + +/** + @name Limits for SIZE_T and SSIZE_T + + @{ +*/ +#if EVENT__SIZEOF_SIZE_T == 8 +#define EV_SIZE_MAX EV_UINT64_MAX +#define EV_SSIZE_MAX EV_INT64_MAX +#elif EVENT__SIZEOF_SIZE_T == 4 +#define EV_SIZE_MAX EV_UINT32_MAX +#define EV_SSIZE_MAX EV_INT32_MAX +#elif defined(EVENT_IN_DOXYGEN_) +#define EV_SIZE_MAX ... +#define EV_SSIZE_MAX ... +#else +#error "No way to define SIZE_MAX" +#endif + +#define EV_SSIZE_MIN ((-EV_SSIZE_MAX) - 1) +/**@}*/ + +#ifdef _WIN32 +#define ev_socklen_t int +#elif defined(EVENT__socklen_t) +#define ev_socklen_t EVENT__socklen_t +#else +#define ev_socklen_t socklen_t +#endif + +#ifdef EVENT__HAVE_STRUCT_SOCKADDR_STORAGE___SS_FAMILY +#if !defined(EVENT__HAVE_STRUCT_SOCKADDR_STORAGE_SS_FAMILY) \ + && !defined(ss_family) +#define ss_family __ss_family +#endif +#endif + +/** + * A type wide enough to hold the output of "socket()" or "accept()". On + * Windows, this is an intptr_t; elsewhere, it is an int. */ +#ifdef _WIN32 +#define evutil_socket_t intptr_t +#else +#define evutil_socket_t int +#endif + +/** + * Structure to hold information about a monotonic timer + * + * Use this with evutil_configure_monotonic_time() and + * evutil_gettime_monotonic(). + * + * This is an opaque structure; you can allocate one using + * evutil_monotonic_timer_new(). + * + * @see evutil_monotonic_timer_new(), evutil_monotonic_timer_free(), + * evutil_configure_monotonic_time(), evutil_gettime_monotonic() + */ +struct evutil_monotonic_timer +#ifdef EVENT_IN_DOXYGEN_ +{/*Empty body so that doxygen will generate documentation here.*/} +#endif +; + +#define EV_MONOT_PRECISE 1 +#define EV_MONOT_FALLBACK 2 + +/** Format a date string using RFC 1123 format (used in HTTP). + * If `tm` is NULL, current system's time will be used. + * The number of characters written will be returned. + * One should check if the return value is smaller than `datelen` to check if + * the result is truncated or not. + */ +EVENT2_EXPORT_SYMBOL int +evutil_date_rfc1123(char *date, const size_t datelen, const struct tm *tm); + +/** Allocate a new struct evutil_monotonic_timer for use with the + * evutil_configure_monotonic_time() and evutil_gettime_monotonic() + * functions. You must configure the timer with + * evutil_configure_monotonic_time() before using it. + */ +EVENT2_EXPORT_SYMBOL +struct evutil_monotonic_timer * evutil_monotonic_timer_new(void); + +/** Free a struct evutil_monotonic_timer that was allocated using + * evutil_monotonic_timer_new(). + */ +EVENT2_EXPORT_SYMBOL +void evutil_monotonic_timer_free(struct evutil_monotonic_timer *timer); + +/** Set up a struct evutil_monotonic_timer; flags can include + * EV_MONOT_PRECISE and EV_MONOT_FALLBACK. + */ +EVENT2_EXPORT_SYMBOL +int evutil_configure_monotonic_time(struct evutil_monotonic_timer *timer, + int flags); + +/** Query the current monotonic time from a struct evutil_monotonic_timer + * previously configured with evutil_configure_monotonic_time(). Monotonic + * time is guaranteed never to run in reverse, but is not necessarily epoch- + * based, or relative to any other definite point. Use it to make reliable + * measurements of elapsed time between events even when the system time + * may be changed. + * + * It is not safe to use this funtion on the same timer from multiple + * threads. + */ +EVENT2_EXPORT_SYMBOL +int evutil_gettime_monotonic(struct evutil_monotonic_timer *timer, + struct timeval *tp); + +/** Create two new sockets that are connected to each other. + + On Unix, this simply calls socketpair(). On Windows, it uses the + loopback network interface on 127.0.0.1, and only + AF_INET,SOCK_STREAM are supported. + + (This may fail on some Windows hosts where firewall software has cleverly + decided to keep 127.0.0.1 from talking to itself.) + + Parameters and return values are as for socketpair() +*/ +EVENT2_EXPORT_SYMBOL +int evutil_socketpair(int d, int type, int protocol, evutil_socket_t sv[2]); +/** Do platform-specific operations as needed to make a socket nonblocking. + + @param sock The socket to make nonblocking + @return 0 on success, -1 on failure + */ +EVENT2_EXPORT_SYMBOL +int evutil_make_socket_nonblocking(evutil_socket_t sock); + +/** Do platform-specific operations to make a listener socket reusable. + + Specifically, we want to make sure that another program will be able + to bind this address right after we've closed the listener. + + This differs from Windows's interpretation of "reusable", which + allows multiple listeners to bind the same address at the same time. + + @param sock The socket to make reusable + @return 0 on success, -1 on failure + */ +EVENT2_EXPORT_SYMBOL +int evutil_make_listen_socket_reuseable(evutil_socket_t sock); + +/** Do platform-specific operations to make a listener port reusable. + + Specifically, we want to make sure that multiple programs which also + set the same socket option will be able to bind, listen at the same time. + + This is a feature available only to Linux 3.9+ + + @param sock The socket to make reusable + @return 0 on success, -1 on failure + */ +EVENT2_EXPORT_SYMBOL +int evutil_make_listen_socket_reuseable_port(evutil_socket_t sock); + +/** Do platform-specific operations as needed to close a socket upon a + successful execution of one of the exec*() functions. + + @param sock The socket to be closed + @return 0 on success, -1 on failure + */ +EVENT2_EXPORT_SYMBOL +int evutil_make_socket_closeonexec(evutil_socket_t sock); + +/** Do the platform-specific call needed to close a socket returned from + socket() or accept(). + + @param sock The socket to be closed + @return 0 on success, -1 on failure + */ +EVENT2_EXPORT_SYMBOL +int evutil_closesocket(evutil_socket_t sock); +#define EVUTIL_CLOSESOCKET(s) evutil_closesocket(s) + +/** Do platform-specific operations, if possible, to make a tcp listener + * socket defer accept()s until there is data to read. + * + * Not all platforms support this. You don't want to do this for every + * listener socket: only the ones that implement a protocol where the + * client transmits before the server needs to respond. + * + * @param sock The listening socket to to make deferred + * @return 0 on success (whether the operation is supported or not), + * -1 on failure +*/ +EVENT2_EXPORT_SYMBOL +int evutil_make_tcp_listen_socket_deferred(evutil_socket_t sock); + +#ifdef _WIN32 +/** Return the most recent socket error. Not idempotent on all platforms. */ +#define EVUTIL_SOCKET_ERROR() WSAGetLastError() +/** Replace the most recent socket error with errcode */ +#define EVUTIL_SET_SOCKET_ERROR(errcode) \ + do { WSASetLastError(errcode); } while (0) +/** Return the most recent socket error to occur on sock. */ +EVENT2_EXPORT_SYMBOL +int evutil_socket_geterror(evutil_socket_t sock); +/** Convert a socket error to a string. */ +EVENT2_EXPORT_SYMBOL +const char *evutil_socket_error_to_string(int errcode); +#elif defined(EVENT_IN_DOXYGEN_) +/** + @name Socket error functions + + These functions are needed for making programs compatible between + Windows and Unix-like platforms. + + You see, Winsock handles socket errors differently from the rest of + the world. Elsewhere, a socket error is like any other error and is + stored in errno. But winsock functions require you to retrieve the + error with a special function, and don't let you use strerror for + the error codes. And handling EWOULDBLOCK is ... different. + + @{ +*/ +/** Return the most recent socket error. Not idempotent on all platforms. */ +#define EVUTIL_SOCKET_ERROR() ... +/** Replace the most recent socket error with errcode */ +#define EVUTIL_SET_SOCKET_ERROR(errcode) ... +/** Return the most recent socket error to occur on sock. */ +#define evutil_socket_geterror(sock) ... +/** Convert a socket error to a string. */ +#define evutil_socket_error_to_string(errcode) ... +/**@}*/ +#else +#define EVUTIL_SOCKET_ERROR() (errno) +#define EVUTIL_SET_SOCKET_ERROR(errcode) \ + do { errno = (errcode); } while (0) +#define evutil_socket_geterror(sock) (errno) +#define evutil_socket_error_to_string(errcode) (strerror(errcode)) +#endif + + +/** + * @name Manipulation macros for struct timeval. + * + * We define replacements + * for timeradd, timersub, timerclear, timercmp, and timerisset. + * + * @{ + */ +#ifdef EVENT__HAVE_TIMERADD +#define evutil_timeradd(tvp, uvp, vvp) timeradd((tvp), (uvp), (vvp)) +#define evutil_timersub(tvp, uvp, vvp) timersub((tvp), (uvp), (vvp)) +#else +#define evutil_timeradd(tvp, uvp, vvp) \ + do { \ + (vvp)->tv_sec = (tvp)->tv_sec + (uvp)->tv_sec; \ + (vvp)->tv_usec = (tvp)->tv_usec + (uvp)->tv_usec; \ + if ((vvp)->tv_usec >= 1000000) { \ + (vvp)->tv_sec++; \ + (vvp)->tv_usec -= 1000000; \ + } \ + } while (0) +#define evutil_timersub(tvp, uvp, vvp) \ + do { \ + (vvp)->tv_sec = (tvp)->tv_sec - (uvp)->tv_sec; \ + (vvp)->tv_usec = (tvp)->tv_usec - (uvp)->tv_usec; \ + if ((vvp)->tv_usec < 0) { \ + (vvp)->tv_sec--; \ + (vvp)->tv_usec += 1000000; \ + } \ + } while (0) +#endif /* !EVENT__HAVE_TIMERADD */ + +#ifdef EVENT__HAVE_TIMERCLEAR +#define evutil_timerclear(tvp) timerclear(tvp) +#else +#define evutil_timerclear(tvp) (tvp)->tv_sec = (tvp)->tv_usec = 0 +#endif +/**@}*/ + +/** Return true iff the tvp is related to uvp according to the relational + * operator cmp. Recognized values for cmp are ==, <=, <, >=, and >. */ +#define evutil_timercmp(tvp, uvp, cmp) \ + (((tvp)->tv_sec == (uvp)->tv_sec) ? \ + ((tvp)->tv_usec cmp (uvp)->tv_usec) : \ + ((tvp)->tv_sec cmp (uvp)->tv_sec)) + +#ifdef EVENT__HAVE_TIMERISSET +#define evutil_timerisset(tvp) timerisset(tvp) +#else +#define evutil_timerisset(tvp) ((tvp)->tv_sec || (tvp)->tv_usec) +#endif + +/** Replacement for offsetof on platforms that don't define it. */ +#ifdef offsetof +#define evutil_offsetof(type, field) offsetof(type, field) +#else +#define evutil_offsetof(type, field) ((off_t)(&((type *)0)->field)) +#endif + +/* big-int related functions */ +/** Parse a 64-bit value from a string. Arguments are as for strtol. */ +EVENT2_EXPORT_SYMBOL +ev_int64_t evutil_strtoll(const char *s, char **endptr, int base); + +/** Replacement for gettimeofday on platforms that lack it. */ +#ifdef EVENT__HAVE_GETTIMEOFDAY +#define evutil_gettimeofday(tv, tz) gettimeofday((tv), (tz)) +#else +struct timezone; +EVENT2_EXPORT_SYMBOL +int evutil_gettimeofday(struct timeval *tv, struct timezone *tz); +#endif + +/** Replacement for snprintf to get consistent behavior on platforms for + which the return value of snprintf does not conform to C99. + */ +EVENT2_EXPORT_SYMBOL +int evutil_snprintf(char *buf, size_t buflen, const char *format, ...) +#ifdef __GNUC__ + __attribute__((format(printf, 3, 4))) +#endif +; +/** Replacement for vsnprintf to get consistent behavior on platforms for + which the return value of snprintf does not conform to C99. + */ +EVENT2_EXPORT_SYMBOL +int evutil_vsnprintf(char *buf, size_t buflen, const char *format, va_list ap) +#ifdef __GNUC__ + __attribute__((format(printf, 3, 0))) +#endif +; + +/** Replacement for inet_ntop for platforms which lack it. */ +EVENT2_EXPORT_SYMBOL +const char *evutil_inet_ntop(int af, const void *src, char *dst, size_t len); +/** Replacement for inet_pton for platforms which lack it. */ +EVENT2_EXPORT_SYMBOL +int evutil_inet_pton(int af, const char *src, void *dst); +struct sockaddr; + +/** Parse an IPv4 or IPv6 address, with optional port, from a string. + + Recognized formats are: + - [IPv6Address]:port + - [IPv6Address] + - IPv6Address + - IPv4Address:port + - IPv4Address + + If no port is specified, the port in the output is set to 0. + + @param str The string to parse. + @param out A struct sockaddr to hold the result. This should probably be + a struct sockaddr_storage. + @param outlen A pointer to the number of bytes that that 'out' can safely + hold. Set to the number of bytes used in 'out' on success. + @return -1 if the address is not well-formed, if the port is out of range, + or if out is not large enough to hold the result. Otherwise returns + 0 on success. +*/ +EVENT2_EXPORT_SYMBOL +int evutil_parse_sockaddr_port(const char *str, struct sockaddr *out, int *outlen); + +/** Compare two sockaddrs; return 0 if they are equal, or less than 0 if sa1 + * preceeds sa2, or greater than 0 if sa1 follows sa2. If include_port is + * true, consider the port as well as the address. Only implemented for + * AF_INET and AF_INET6 addresses. The ordering is not guaranteed to remain + * the same between Libevent versions. */ +EVENT2_EXPORT_SYMBOL +int evutil_sockaddr_cmp(const struct sockaddr *sa1, const struct sockaddr *sa2, + int include_port); + +/** As strcasecmp, but always compares the characters in locale-independent + ASCII. That's useful if you're handling data in ASCII-based protocols. + */ +EVENT2_EXPORT_SYMBOL +int evutil_ascii_strcasecmp(const char *str1, const char *str2); +/** As strncasecmp, but always compares the characters in locale-independent + ASCII. That's useful if you're handling data in ASCII-based protocols. + */ +EVENT2_EXPORT_SYMBOL +int evutil_ascii_strncasecmp(const char *str1, const char *str2, size_t n); + +/* Here we define evutil_addrinfo to the native addrinfo type, or redefine it + * if this system has no getaddrinfo(). */ +#ifdef EVENT__HAVE_STRUCT_ADDRINFO +#define evutil_addrinfo addrinfo +#else +/** A definition of struct addrinfo for systems that lack it. + + (This is just an alias for struct addrinfo if the system defines + struct addrinfo.) +*/ +struct evutil_addrinfo { + int ai_flags; /* AI_PASSIVE, AI_CANONNAME, AI_NUMERICHOST */ + int ai_family; /* PF_xxx */ + int ai_socktype; /* SOCK_xxx */ + int ai_protocol; /* 0 or IPPROTO_xxx for IPv4 and IPv6 */ + size_t ai_addrlen; /* length of ai_addr */ + char *ai_canonname; /* canonical name for nodename */ + struct sockaddr *ai_addr; /* binary address */ + struct evutil_addrinfo *ai_next; /* next structure in linked list */ +}; +#endif +/** @name evutil_getaddrinfo() error codes + + These values are possible error codes for evutil_getaddrinfo() and + related functions. + + @{ +*/ +#if defined(EAI_ADDRFAMILY) && defined(EVENT__HAVE_GETADDRINFO) +#define EVUTIL_EAI_ADDRFAMILY EAI_ADDRFAMILY +#else +#define EVUTIL_EAI_ADDRFAMILY -901 +#endif +#if defined(EAI_AGAIN) && defined(EVENT__HAVE_GETADDRINFO) +#define EVUTIL_EAI_AGAIN EAI_AGAIN +#else +#define EVUTIL_EAI_AGAIN -902 +#endif +#if defined(EAI_BADFLAGS) && defined(EVENT__HAVE_GETADDRINFO) +#define EVUTIL_EAI_BADFLAGS EAI_BADFLAGS +#else +#define EVUTIL_EAI_BADFLAGS -903 +#endif +#if defined(EAI_FAIL) && defined(EVENT__HAVE_GETADDRINFO) +#define EVUTIL_EAI_FAIL EAI_FAIL +#else +#define EVUTIL_EAI_FAIL -904 +#endif +#if defined(EAI_FAMILY) && defined(EVENT__HAVE_GETADDRINFO) +#define EVUTIL_EAI_FAMILY EAI_FAMILY +#else +#define EVUTIL_EAI_FAMILY -905 +#endif +#if defined(EAI_MEMORY) && defined(EVENT__HAVE_GETADDRINFO) +#define EVUTIL_EAI_MEMORY EAI_MEMORY +#else +#define EVUTIL_EAI_MEMORY -906 +#endif +/* This test is a bit complicated, since some MS SDKs decide to + * remove NODATA or redefine it to be the same as NONAME, in a + * fun interpretation of RFC 2553 and RFC 3493. */ +#if defined(EAI_NODATA) && defined(EVENT__HAVE_GETADDRINFO) && (!defined(EAI_NONAME) || EAI_NODATA != EAI_NONAME) +#define EVUTIL_EAI_NODATA EAI_NODATA +#else +#define EVUTIL_EAI_NODATA -907 +#endif +#if defined(EAI_NONAME) && defined(EVENT__HAVE_GETADDRINFO) +#define EVUTIL_EAI_NONAME EAI_NONAME +#else +#define EVUTIL_EAI_NONAME -908 +#endif +#if defined(EAI_SERVICE) && defined(EVENT__HAVE_GETADDRINFO) +#define EVUTIL_EAI_SERVICE EAI_SERVICE +#else +#define EVUTIL_EAI_SERVICE -909 +#endif +#if defined(EAI_SOCKTYPE) && defined(EVENT__HAVE_GETADDRINFO) +#define EVUTIL_EAI_SOCKTYPE EAI_SOCKTYPE +#else +#define EVUTIL_EAI_SOCKTYPE -910 +#endif +#if defined(EAI_SYSTEM) && defined(EVENT__HAVE_GETADDRINFO) +#define EVUTIL_EAI_SYSTEM EAI_SYSTEM +#else +#define EVUTIL_EAI_SYSTEM -911 +#endif + +#define EVUTIL_EAI_CANCEL -90001 + +#if defined(AI_PASSIVE) && defined(EVENT__HAVE_GETADDRINFO) +#define EVUTIL_AI_PASSIVE AI_PASSIVE +#else +#define EVUTIL_AI_PASSIVE 0x1000 +#endif +#if defined(AI_CANONNAME) && defined(EVENT__HAVE_GETADDRINFO) +#define EVUTIL_AI_CANONNAME AI_CANONNAME +#else +#define EVUTIL_AI_CANONNAME 0x2000 +#endif +#if defined(AI_NUMERICHOST) && defined(EVENT__HAVE_GETADDRINFO) +#define EVUTIL_AI_NUMERICHOST AI_NUMERICHOST +#else +#define EVUTIL_AI_NUMERICHOST 0x4000 +#endif +#if defined(AI_NUMERICSERV) && defined(EVENT__HAVE_GETADDRINFO) +#define EVUTIL_AI_NUMERICSERV AI_NUMERICSERV +#else +#define EVUTIL_AI_NUMERICSERV 0x8000 +#endif +#if defined(AI_V4MAPPED) && defined(EVENT__HAVE_GETADDRINFO) +#define EVUTIL_AI_V4MAPPED AI_V4MAPPED +#else +#define EVUTIL_AI_V4MAPPED 0x10000 +#endif +#if defined(AI_ALL) && defined(EVENT__HAVE_GETADDRINFO) +#define EVUTIL_AI_ALL AI_ALL +#else +#define EVUTIL_AI_ALL 0x20000 +#endif +#if defined(AI_ADDRCONFIG) && defined(EVENT__HAVE_GETADDRINFO) +#define EVUTIL_AI_ADDRCONFIG AI_ADDRCONFIG +#else +#define EVUTIL_AI_ADDRCONFIG 0x40000 +#endif +/**@}*/ + +struct evutil_addrinfo; +/** + * This function clones getaddrinfo for systems that don't have it. For full + * details, see RFC 3493, section 6.1. + * + * Limitations: + * - When the system has no getaddrinfo, we fall back to gethostbyname_r or + * gethostbyname, with their attendant issues. + * - The AI_V4MAPPED and AI_ALL flags are not currently implemented. + * + * For a nonblocking variant, see evdns_getaddrinfo. + */ +EVENT2_EXPORT_SYMBOL +int evutil_getaddrinfo(const char *nodename, const char *servname, + const struct evutil_addrinfo *hints_in, struct evutil_addrinfo **res); + +/** Release storage allocated by evutil_getaddrinfo or evdns_getaddrinfo. */ +EVENT2_EXPORT_SYMBOL +void evutil_freeaddrinfo(struct evutil_addrinfo *ai); + +EVENT2_EXPORT_SYMBOL +const char *evutil_gai_strerror(int err); + +/** Generate n bytes of secure pseudorandom data, and store them in buf. + * + * Current versions of Libevent use an ARC4-based random number generator, + * seeded using the platform's entropy source (/dev/urandom on Unix-like + * systems; CryptGenRandom on Windows). This is not actually as secure as it + * should be: ARC4 is a pretty lousy cipher, and the current implementation + * provides only rudimentary prediction- and backtracking-resistance. Don't + * use this for serious cryptographic applications. + */ +EVENT2_EXPORT_SYMBOL +void evutil_secure_rng_get_bytes(void *buf, size_t n); + +/** + * Seed the secure random number generator if needed, and return 0 on + * success or -1 on failure. + * + * It is okay to call this function more than once; it will still return + * 0 if the RNG has been successfully seeded and -1 if it can't be + * seeded. + * + * Ordinarily you don't need to call this function from your own code; + * Libevent will seed the RNG itself the first time it needs good random + * numbers. You only need to call it if (a) you want to double-check + * that one of the seeding methods did succeed, or (b) you plan to drop + * the capability to seed (by chrooting, or dropping capabilities, or + * whatever), and you want to make sure that seeding happens before your + * program loses the ability to do it. + */ +EVENT2_EXPORT_SYMBOL +int evutil_secure_rng_init(void); + +/** + * Set a filename to use in place of /dev/urandom for seeding the secure + * PRNG. Return 0 on success, -1 on failure. + * + * Call this function BEFORE calling any other initialization or RNG + * functions. + * + * (This string will _NOT_ be copied internally. Do not free it while any + * user of the secure RNG might be running. Don't pass anything other than a + * real /dev/...random device file here, or you might lose security.) + * + * This API is unstable, and might change in a future libevent version. + */ +EVENT2_EXPORT_SYMBOL +int evutil_secure_rng_set_urandom_device_file(char *fname); + +/** Seed the random number generator with extra random bytes. + + You should almost never need to call this function; it should be + sufficient to invoke evutil_secure_rng_init(), or let Libevent take + care of calling evutil_secure_rng_init() on its own. + + If you call this function as a _replacement_ for the regular + entropy sources, then you need to be sure that your input + contains a fairly large amount of strong entropy. Doing so is + notoriously hard: most people who try get it wrong. Watch out! + + @param dat a buffer full of a strong source of random numbers + @param datlen the number of bytes to read from datlen + */ +EVENT2_EXPORT_SYMBOL +void evutil_secure_rng_add_bytes(const char *dat, size_t datlen); + +#ifdef __cplusplus +} +#endif + +#endif /* EVENT1_EVUTIL_H_INCLUDED_ */ diff --git a/include/event2/visibility.h b/include/event2/visibility.h new file mode 100644 index 000000000000..fb16dbeeddd0 --- /dev/null +++ b/include/event2/visibility.h @@ -0,0 +1,50 @@ +/* -*- Mode: C; tab-width: 4; c-basic-offset: 4; indent-tabs-mode: nil -*- */ +/* + * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#ifndef EVENT2_VISIBILITY_H_INCLUDED_ +#define EVENT2_VISIBILITY_H_INCLUDED_ + +#include <event2/event-config.h> + +#if defined(event_EXPORTS) || defined(event_extra_EXPORTS) || defined(event_core_EXPORTS) +# if defined (__SUNPRO_C) && (__SUNPRO_C >= 0x550) +# define EVENT2_EXPORT_SYMBOL __global +# elif defined __GNUC__ +# define EVENT2_EXPORT_SYMBOL __attribute__ ((visibility("default"))) +# elif defined(_MSC_VER) +# define EVENT2_EXPORT_SYMBOL extern __declspec(dllexport) +# else +# define EVENT2_EXPORT_SYMBOL /* unknown compiler */ +# endif +#else +# if defined(EVENT__NEED_DLLIMPORT) && defined(_MSC_VER) && !defined(EVENT_BUILDING_REGRESS_TEST) +# define EVENT2_EXPORT_SYMBOL extern __declspec(dllimport) +# else +# define EVENT2_EXPORT_SYMBOL +# endif +#endif + +#endif /* EVENT2_VISIBILITY_H_INCLUDED_ */ |