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Diffstat (limited to 'lib/libthr/thread/thr_spec.c')
| -rw-r--r-- | lib/libthr/thread/thr_spec.c | 246 |
1 files changed, 246 insertions, 0 deletions
diff --git a/lib/libthr/thread/thr_spec.c b/lib/libthr/thread/thr_spec.c new file mode 100644 index 0000000000000..faa88e2fc8bac --- /dev/null +++ b/lib/libthr/thread/thr_spec.c @@ -0,0 +1,246 @@ +/*- + * SPDX-License-Identifier: BSD-3-Clause + * + * Copyright (c) 1995 John Birrell <jb@cimlogic.com.au>. + * 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. Neither the name of the author nor the names of any co-contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL 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 "namespace.h" +#include <sys/mman.h> +#include <signal.h> +#include <stdlib.h> +#include <string.h> +#include <errno.h> +#include <pthread.h> +#include "un-namespace.h" +#include "libc_private.h" + +#include "thr_private.h" + +/* Used in symbol lookup of libthread_db */ +struct pthread_key _thread_keytable[PTHREAD_KEYS_MAX]; + +__weak_reference(_pthread_key_create, pthread_key_create); +__weak_reference(_pthread_key_delete, pthread_key_delete); +__weak_reference(_pthread_getspecific, pthread_getspecific); +__weak_reference(_pthread_setspecific, pthread_setspecific); + + +int +_pthread_key_create(pthread_key_t *key, void (*destructor)(void *)) +{ + struct pthread *curthread; + int i; + + _thr_check_init(); + + curthread = _get_curthread(); + + THR_LOCK_ACQUIRE(curthread, &_keytable_lock); + for (i = 0; i < PTHREAD_KEYS_MAX; i++) { + + if (_thread_keytable[i].allocated == 0) { + _thread_keytable[i].allocated = 1; + _thread_keytable[i].destructor = destructor; + _thread_keytable[i].seqno++; + + THR_LOCK_RELEASE(curthread, &_keytable_lock); + *key = i + 1; + return (0); + } + + } + THR_LOCK_RELEASE(curthread, &_keytable_lock); + return (EAGAIN); +} + +int +_pthread_key_delete(pthread_key_t userkey) +{ + struct pthread *curthread; + int key, ret; + + key = userkey - 1; + if ((unsigned int)key >= PTHREAD_KEYS_MAX) + return (EINVAL); + curthread = _get_curthread(); + THR_LOCK_ACQUIRE(curthread, &_keytable_lock); + if (_thread_keytable[key].allocated) { + _thread_keytable[key].allocated = 0; + ret = 0; + } else { + ret = EINVAL; + } + THR_LOCK_RELEASE(curthread, &_keytable_lock); + return (ret); +} + +void +_thread_cleanupspecific(void) +{ + struct pthread *curthread; + void (*destructor)(void *); + const void *data; + int i, key; + + curthread = _get_curthread(); + if (curthread->specific == NULL) + return; + THR_LOCK_ACQUIRE(curthread, &_keytable_lock); + for (i = 0; i < PTHREAD_DESTRUCTOR_ITERATIONS && + curthread->specific_data_count > 0; i++) { + for (key = 0; key < PTHREAD_KEYS_MAX && + curthread->specific_data_count > 0; key++) { + destructor = NULL; + + if (_thread_keytable[key].allocated && + (curthread->specific[key].data != NULL)) { + if (curthread->specific[key].seqno == + _thread_keytable[key].seqno) { + data = curthread->specific[key].data; + destructor = _thread_keytable[key]. + destructor; + } + curthread->specific[key].data = NULL; + curthread->specific_data_count--; + } else if (curthread->specific[key].data != NULL) { + /* + * This can happen if the key is + * deleted via pthread_key_delete + * without first setting the value to + * NULL in all threads. POSIX says + * that the destructor is not invoked + * in this case. + */ + curthread->specific[key].data = NULL; + curthread->specific_data_count--; + } + + /* + * If there is a destructor, call it with the + * key table entry unlocked. + */ + if (destructor != NULL) { + THR_LOCK_RELEASE(curthread, &_keytable_lock); + destructor(__DECONST(void *, data)); + THR_LOCK_ACQUIRE(curthread, &_keytable_lock); + } + } + } + THR_LOCK_RELEASE(curthread, &_keytable_lock); + munmap(curthread->specific, PTHREAD_KEYS_MAX * sizeof(struct + pthread_specific_elem)); + curthread->specific = NULL; + if (curthread->specific_data_count > 0) { + stderr_debug("Thread %p has exited with leftover " + "thread-specific data after %d destructor iterations\n", + curthread, PTHREAD_DESTRUCTOR_ITERATIONS); + } +} + +int +_pthread_setspecific(pthread_key_t userkey, const void *value) +{ + struct pthread *pthread; + void *tmp; + pthread_key_t key; + + key = userkey - 1; + if ((unsigned int)key >= PTHREAD_KEYS_MAX || + !_thread_keytable[key].allocated) + return (EINVAL); + + pthread = _get_curthread(); + if (pthread->specific == NULL) { + tmp = mmap(NULL, PTHREAD_KEYS_MAX * + sizeof(struct pthread_specific_elem), + PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0); + if (tmp == MAP_FAILED) + return (ENOMEM); + pthread->specific = tmp; + } + if (pthread->specific[key].data == NULL) { + if (value != NULL) + pthread->specific_data_count++; + } else if (value == NULL) + pthread->specific_data_count--; + pthread->specific[key].data = value; + pthread->specific[key].seqno = _thread_keytable[key].seqno; + return (0); +} + +void * +_pthread_getspecific(pthread_key_t userkey) +{ + struct pthread *pthread; + const void *data; + pthread_key_t key; + + /* Check if there is specific data. */ + key = userkey - 1; + if ((unsigned int)key >= PTHREAD_KEYS_MAX) + return (NULL); + + pthread = _get_curthread(); + /* Check if this key has been used before. */ + if (_thread_keytable[key].allocated && pthread->specific != NULL && + pthread->specific[key].seqno == _thread_keytable[key].seqno) { + /* Return the value: */ + data = pthread->specific[key].data; + } else { + /* + * This key has not been used before, so return NULL + * instead. + */ + data = NULL; + } + return (__DECONST(void *, data)); +} + +void +_thr_tsd_unload(struct dl_phdr_info *phdr_info) +{ + struct pthread *curthread; + void (*destructor)(void *); + int key; + + curthread = _get_curthread(); + THR_LOCK_ACQUIRE(curthread, &_keytable_lock); + for (key = 0; key < PTHREAD_KEYS_MAX; key++) { + if (!_thread_keytable[key].allocated) + continue; + destructor = _thread_keytable[key].destructor; + if (destructor == NULL) + continue; + if (__elf_phdr_match_addr(phdr_info, destructor)) + _thread_keytable[key].destructor = NULL; + } + THR_LOCK_RELEASE(curthread, &_keytable_lock); +} |