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-rw-r--r--lib/libstand/gzipfs.c324
1 files changed, 324 insertions, 0 deletions
diff --git a/lib/libstand/gzipfs.c b/lib/libstand/gzipfs.c
new file mode 100644
index 000000000000..00c8f8f73634
--- /dev/null
+++ b/lib/libstand/gzipfs.c
@@ -0,0 +1,324 @@
+/*
+ * Copyright (c) 1998 Michael Smith.
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include "stand.h"
+
+#include <sys/stat.h>
+#include <string.h>
+#include <zlib.h>
+
+#define Z_BUFSIZE 2048 /* XXX larger? */
+
+struct z_file
+{
+ int zf_rawfd;
+ z_stream zf_zstream;
+ char zf_buf[Z_BUFSIZE];
+};
+
+static int zf_fill(struct z_file *z);
+static int zf_open(const char *path, struct open_file *f);
+static int zf_close(struct open_file *f);
+static int zf_read(struct open_file *f, void *buf, size_t size, size_t *resid);
+static off_t zf_seek(struct open_file *f, off_t offset, int where);
+static int zf_stat(struct open_file *f, struct stat *sb);
+
+struct fs_ops zipfs_fsops = {
+ "zip",
+ zf_open,
+ zf_close,
+ zf_read,
+ null_write,
+ zf_seek,
+ zf_stat,
+ null_readdir
+};
+
+#if 0
+void *
+calloc(int items, size_t size)
+{
+ return(malloc(items * size));
+}
+#endif
+
+static int
+zf_fill(struct z_file *zf)
+{
+ int result;
+ int req;
+
+ req = Z_BUFSIZE - zf->zf_zstream.avail_in;
+ result = 0;
+
+ /* If we need more */
+ if (req > 0) {
+ /* move old data to bottom of buffer */
+ if (req < Z_BUFSIZE)
+ bcopy(zf->zf_buf + req, zf->zf_buf, Z_BUFSIZE - req);
+
+ /* read to fill buffer and update availibility data */
+ result = read(zf->zf_rawfd, zf->zf_buf + zf->zf_zstream.avail_in, req);
+ zf->zf_zstream.next_in = zf->zf_buf;
+ if (result >= 0)
+ zf->zf_zstream.avail_in += result;
+ }
+ return(result);
+}
+
+/*
+ * Adapted from get_byte/check_header in libz
+ *
+ * Returns 0 if the header is OK, nonzero if not.
+ */
+static int
+get_byte(struct z_file *zf)
+{
+ if ((zf->zf_zstream.avail_in == 0) && (zf_fill(zf) == -1))
+ return(-1);
+ zf->zf_zstream.avail_in--;
+ return(*(zf->zf_zstream.next_in)++);
+}
+
+static int gz_magic[2] = {0x1f, 0x8b}; /* gzip magic header */
+
+/* gzip flag byte */
+#define ASCII_FLAG 0x01 /* bit 0 set: file probably ascii text */
+#define HEAD_CRC 0x02 /* bit 1 set: header CRC present */
+#define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */
+#define ORIG_NAME 0x08 /* bit 3 set: original file name present */
+#define COMMENT 0x10 /* bit 4 set: file comment present */
+#define RESERVED 0xE0 /* bits 5..7: reserved */
+
+static int
+check_header(struct z_file *zf)
+{
+ int method; /* method byte */
+ int flags; /* flags byte */
+ uInt len;
+ int c;
+
+ /* Check the gzip magic header */
+ for (len = 0; len < 2; len++) {
+ c = get_byte(zf);
+ if (c != gz_magic[len]) {
+ return(1);
+ }
+ }
+ method = get_byte(zf);
+ flags = get_byte(zf);
+ if (method != Z_DEFLATED || (flags & RESERVED) != 0) {
+ return(1);
+ }
+
+ /* Discard time, xflags and OS code: */
+ for (len = 0; len < 6; len++) (void)get_byte(zf);
+
+ if ((flags & EXTRA_FIELD) != 0) { /* skip the extra field */
+ len = (uInt)get_byte(zf);
+ len += ((uInt)get_byte(zf))<<8;
+ /* len is garbage if EOF but the loop below will quit anyway */
+ while (len-- != 0 && get_byte(zf) != -1) ;
+ }
+ if ((flags & ORIG_NAME) != 0) { /* skip the original file name */
+ while ((c = get_byte(zf)) != 0 && c != -1) ;
+ }
+ if ((flags & COMMENT) != 0) { /* skip the .gz file comment */
+ while ((c = get_byte(zf)) != 0 && c != -1) ;
+ }
+ if ((flags & HEAD_CRC) != 0) { /* skip the header crc */
+ for (len = 0; len < 2; len++) c = get_byte(zf);
+ }
+ /* if there's data left, we're in business */
+ return((c == -1) ? 1 : 0);
+}
+
+static int
+zf_open(const char *fname, struct open_file *f)
+{
+ static char *zfname;
+ int rawfd;
+ struct z_file *zf;
+ char *cp;
+ int error;
+ struct stat sb;
+
+ /* Have to be in "just read it" mode */
+ if (f->f_flags != F_READ)
+ return(EPERM);
+
+ /* If the name already ends in .gz or .bz2, ignore it */
+ if ((cp = strrchr(fname, '.')) && (!strcmp(cp, ".gz")
+ || !strcmp(cp, ".bz2") || !strcmp(cp, ".split")))
+ return(ENOENT);
+
+ /* Construct new name */
+ zfname = malloc(strlen(fname) + 4);
+ if (zfname == NULL)
+ return(ENOMEM);
+ sprintf(zfname, "%s.gz", fname);
+
+ /* Try to open the compressed datafile */
+ rawfd = open(zfname, O_RDONLY);
+ free(zfname);
+ if (rawfd == -1)
+ return(ENOENT);
+
+ if (fstat(rawfd, &sb) < 0) {
+ printf("zf_open: stat failed\n");
+ close(rawfd);
+ return(ENOENT);
+ }
+ if (!S_ISREG(sb.st_mode)) {
+ printf("zf_open: not a file\n");
+ close(rawfd);
+ return(EISDIR); /* best guess */
+ }
+
+ /* Allocate a z_file structure, populate it */
+ zf = malloc(sizeof(struct z_file));
+ if (zf == NULL)
+ return(ENOMEM);
+ bzero(zf, sizeof(struct z_file));
+ zf->zf_rawfd = rawfd;
+
+ /* Verify that the file is gzipped (XXX why do this afterwards?) */
+ if (check_header(zf)) {
+ close(zf->zf_rawfd);
+ inflateEnd(&(zf->zf_zstream));
+ free(zf);
+ return(EFTYPE);
+ }
+
+ /* Initialise the inflation engine */
+ if ((error = inflateInit2(&(zf->zf_zstream), -15)) != Z_OK) {
+ printf("zf_open: inflateInit returned %d : %s\n", error, zf->zf_zstream.msg);
+ close(zf->zf_rawfd);
+ free(zf);
+ return(EIO);
+ }
+
+ /* Looks OK, we'll take it */
+ f->f_fsdata = zf;
+ return(0);
+}
+
+static int
+zf_close(struct open_file *f)
+{
+ struct z_file *zf = (struct z_file *)f->f_fsdata;
+
+ inflateEnd(&(zf->zf_zstream));
+ close(zf->zf_rawfd);
+ free(zf);
+ return(0);
+}
+
+static int
+zf_read(struct open_file *f, void *buf, size_t size, size_t *resid)
+{
+ struct z_file *zf = (struct z_file *)f->f_fsdata;
+ int error;
+
+ zf->zf_zstream.next_out = buf; /* where and how much */
+ zf->zf_zstream.avail_out = size;
+
+ while (zf->zf_zstream.avail_out) {
+ if ((zf->zf_zstream.avail_in == 0) && (zf_fill(zf) == -1)) {
+ printf("zf_read: fill error\n");
+ return(-1);
+ }
+ if (zf->zf_zstream.avail_in == 0) { /* oops, unexpected EOF */
+ printf("zf_read: unexpected EOF\n");
+ break;
+ }
+
+ error = inflate(&zf->zf_zstream, Z_SYNC_FLUSH); /* decompression pass */
+ if (error == Z_STREAM_END) { /* EOF, all done */
+ break;
+ }
+ if (error != Z_OK) { /* argh, decompression error */
+ printf("inflate: %s\n", zf->zf_zstream.msg);
+ errno = EIO;
+ return(-1);
+ }
+ }
+ if (resid != NULL)
+ *resid = zf->zf_zstream.avail_out;
+ return(0);
+}
+
+static off_t
+zf_seek(struct open_file *f, off_t offset, int where)
+{
+ struct z_file *zf = (struct z_file *)f->f_fsdata;
+ off_t target;
+ char discard[16];
+
+ switch (where) {
+ case SEEK_SET:
+ target = offset;
+ break;
+ case SEEK_CUR:
+ target = offset + zf->zf_zstream.total_out;
+ break;
+ default:
+ target = -1;
+ }
+
+ /* Can we get there from here? */
+ if (target < zf->zf_zstream.total_out) {
+ errno = EOFFSET;
+ return -1;
+ }
+
+ /* skip forwards if required */
+ while (target > zf->zf_zstream.total_out) {
+ if (zf_read(f, discard, min(sizeof(discard), target - zf->zf_zstream.total_out), NULL) == -1)
+ return(-1);
+ }
+ /* This is where we are (be honest if we overshot) */
+ return (zf->zf_zstream.total_out);
+}
+
+
+static int
+zf_stat(struct open_file *f, struct stat *sb)
+{
+ struct z_file *zf = (struct z_file *)f->f_fsdata;
+ int result;
+
+ /* stat as normal, but indicate that size is unknown */
+ if ((result = fstat(zf->zf_rawfd, sb)) == 0)
+ sb->st_size = -1;
+ return(result);
+}
+
+
+
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