summaryrefslogtreecommitdiff
path: root/libpthread/linuxthreads/semaphore.c
diff options
context:
space:
mode:
Diffstat (limited to 'libpthread/linuxthreads/semaphore.c')
-rw-r--r--libpthread/linuxthreads/semaphore.c308
1 files changed, 0 insertions, 308 deletions
diff --git a/libpthread/linuxthreads/semaphore.c b/libpthread/linuxthreads/semaphore.c
deleted file mode 100644
index 5be1f5316..000000000
--- a/libpthread/linuxthreads/semaphore.c
+++ /dev/null
@@ -1,308 +0,0 @@
-/* Linuxthreads - a simple clone()-based implementation of Posix */
-/* threads for Linux. */
-/* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy@inria.fr) */
-/* */
-/* This program is free software; you can redistribute it and/or */
-/* modify it under the terms of the GNU Library General Public License */
-/* as published by the Free Software Foundation; either version 2 */
-/* of the License, or (at your option) any later version. */
-/* */
-/* This program is distributed in the hope that it will be useful, */
-/* but WITHOUT ANY WARRANTY; without even the implied warranty of */
-/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the */
-/* GNU Library General Public License for more details. */
-
-/* Semaphores a la POSIX 1003.1b */
-
-#include <features.h>
-#define __USE_GNU
-#include <errno.h>
-#include "pthread.h"
-#include "semaphore.h"
-#include "internals.h"
-#include "spinlock.h"
-#include "restart.h"
-#include "queue.h"
-
-int __new_sem_init(sem_t *sem, int pshared, unsigned int value)
-{
- if (value > SEM_VALUE_MAX) {
- errno = EINVAL;
- return -1;
- }
- if (pshared) {
- errno = ENOSYS;
- return -1;
- }
- __pthread_init_lock(&sem->__sem_lock);
- sem->__sem_value = value;
- sem->__sem_waiting = NULL;
- return 0;
-}
-
-/* Function called by pthread_cancel to remove the thread from
- waiting inside __new_sem_wait. */
-
-static int new_sem_extricate_func(void *obj, pthread_descr th)
-{
- volatile pthread_descr self = thread_self();
- sem_t *sem = obj;
- int did_remove = 0;
-
- __pthread_lock(&sem->__sem_lock, self);
- did_remove = remove_from_queue(&sem->__sem_waiting, th);
- __pthread_unlock(&sem->__sem_lock);
-
- return did_remove;
-}
-
-int __new_sem_wait(sem_t * sem)
-{
- volatile pthread_descr self = thread_self();
- pthread_extricate_if extr;
- int already_canceled = 0;
- int spurious_wakeup_count;
-
- /* Set up extrication interface */
- extr.pu_object = sem;
- extr.pu_extricate_func = new_sem_extricate_func;
-
- __pthread_lock(&sem->__sem_lock, self);
- if (sem->__sem_value > 0) {
- sem->__sem_value--;
- __pthread_unlock(&sem->__sem_lock);
- return 0;
- }
- /* Register extrication interface */
- THREAD_SETMEM(self, p_sem_avail, 0);
- __pthread_set_own_extricate_if(self, &extr);
- /* Enqueue only if not already cancelled. */
- if (!(THREAD_GETMEM(self, p_canceled)
- && THREAD_GETMEM(self, p_cancelstate) == PTHREAD_CANCEL_ENABLE))
- enqueue(&sem->__sem_waiting, self);
- else
- already_canceled = 1;
- __pthread_unlock(&sem->__sem_lock);
-
- if (already_canceled) {
- __pthread_set_own_extricate_if(self, 0);
- pthread_exit(PTHREAD_CANCELED);
- }
-
- /* Wait for sem_post or cancellation, or fall through if already canceled */
- spurious_wakeup_count = 0;
- while (1)
- {
- suspend(self);
- if (THREAD_GETMEM(self, p_sem_avail) == 0
- && (THREAD_GETMEM(self, p_woken_by_cancel) == 0
- || THREAD_GETMEM(self, p_cancelstate) != PTHREAD_CANCEL_ENABLE))
- {
- /* Count resumes that don't belong to us. */
- spurious_wakeup_count++;
- continue;
- }
- break;
- }
- __pthread_set_own_extricate_if(self, 0);
-
- /* Terminate only if the wakeup came from cancellation. */
- /* Otherwise ignore cancellation because we got the semaphore. */
-
- if (THREAD_GETMEM(self, p_woken_by_cancel)
- && THREAD_GETMEM(self, p_cancelstate) == PTHREAD_CANCEL_ENABLE) {
- THREAD_SETMEM(self, p_woken_by_cancel, 0);
- pthread_exit(PTHREAD_CANCELED);
- }
- /* We got the semaphore */
- return 0;
-}
-
-int __new_sem_trywait(sem_t * sem)
-{
- int retval;
-
- __pthread_lock(&sem->__sem_lock, NULL);
- if (sem->__sem_value == 0) {
- errno = EAGAIN;
- retval = -1;
- } else {
- sem->__sem_value--;
- retval = 0;
- }
- __pthread_unlock(&sem->__sem_lock);
- return retval;
-}
-
-int __new_sem_post(sem_t * sem)
-{
- pthread_descr self = thread_self();
- pthread_descr th;
- struct pthread_request request;
-
- if (THREAD_GETMEM(self, p_in_sighandler) == NULL) {
- __pthread_lock(&sem->__sem_lock, self);
- if (sem->__sem_waiting == NULL) {
- if (sem->__sem_value >= SEM_VALUE_MAX) {
- /* Overflow */
- errno = ERANGE;
- __pthread_unlock(&sem->__sem_lock);
- return -1;
- }
- sem->__sem_value++;
- __pthread_unlock(&sem->__sem_lock);
- } else {
- th = dequeue(&sem->__sem_waiting);
- __pthread_unlock(&sem->__sem_lock);
- th->p_sem_avail = 1;
- WRITE_MEMORY_BARRIER();
- restart(th);
- }
- } else {
- /* If we're in signal handler, delegate post operation to
- the thread manager. */
- if (__pthread_manager_request < 0) {
- if (__pthread_initialize_manager() < 0) {
- errno = EAGAIN;
- return -1;
- }
- }
- request.req_kind = REQ_POST;
- request.req_args.post = sem;
- TEMP_FAILURE_RETRY(__libc_write(__pthread_manager_request,
- (char *) &request, sizeof(request)));
- }
- return 0;
-}
-
-int __new_sem_getvalue(sem_t * sem, int * sval)
-{
- *sval = sem->__sem_value;
- return 0;
-}
-
-int __new_sem_destroy(sem_t * sem)
-{
- if (sem->__sem_waiting != NULL) {
- __set_errno (EBUSY);
- return -1;
- }
- return 0;
-}
-
-sem_t *sem_open(const char *name, int oflag, ...)
-{
- __set_errno (ENOSYS);
- return SEM_FAILED;
-}
-
-int sem_close(sem_t *sem)
-{
- __set_errno (ENOSYS);
- return -1;
-}
-
-int sem_unlink(const char *name)
-{
- __set_errno (ENOSYS);
- return -1;
-}
-
-int sem_timedwait(sem_t *sem, const struct timespec *abstime)
-{
- pthread_descr self = thread_self();
- pthread_extricate_if extr;
- int already_canceled = 0;
- int spurious_wakeup_count;
-
- __pthread_lock(&sem->__sem_lock, self);
- if (sem->__sem_value > 0) {
- --sem->__sem_value;
- __pthread_unlock(&sem->__sem_lock);
- return 0;
- }
-
- if (abstime->tv_nsec < 0 || abstime->tv_nsec >= 1000000000) {
- /* The standard requires that if the function would block and the
- time value is illegal, the function returns with an error. */
- __pthread_unlock(&sem->__sem_lock);
- __set_errno (EINVAL);
- return -1;
- }
-
- /* Set up extrication interface */
- extr.pu_object = sem;
- extr.pu_extricate_func = new_sem_extricate_func;
-
- /* Register extrication interface */
- THREAD_SETMEM(self, p_sem_avail, 0);
- __pthread_set_own_extricate_if(self, &extr);
- /* Enqueue only if not already cancelled. */
- if (!(THREAD_GETMEM(self, p_canceled)
- && THREAD_GETMEM(self, p_cancelstate) == PTHREAD_CANCEL_ENABLE))
- enqueue(&sem->__sem_waiting, self);
- else
- already_canceled = 1;
- __pthread_unlock(&sem->__sem_lock);
-
- if (already_canceled) {
- __pthread_set_own_extricate_if(self, 0);
- pthread_exit(PTHREAD_CANCELED);
- }
-
- spurious_wakeup_count = 0;
- while (1)
- {
- if (timedsuspend(self, abstime) == 0) {
- int was_on_queue;
-
- /* __pthread_lock will queue back any spurious restarts that
- may happen to it. */
-
- __pthread_lock(&sem->__sem_lock, self);
- was_on_queue = remove_from_queue(&sem->__sem_waiting, self);
- __pthread_unlock(&sem->__sem_lock);
-
- if (was_on_queue) {
- __pthread_set_own_extricate_if(self, 0);
- __set_errno (ETIMEDOUT);
- return -1;
- }
-
- /* Eat the outstanding restart() from the signaller */
- suspend(self);
- }
-
- if (THREAD_GETMEM(self, p_sem_avail) == 0
- && (THREAD_GETMEM(self, p_woken_by_cancel) == 0
- || THREAD_GETMEM(self, p_cancelstate) != PTHREAD_CANCEL_ENABLE))
- {
- /* Count resumes that don't belong to us. */
- spurious_wakeup_count++;
- continue;
- }
- break;
- }
-
- __pthread_set_own_extricate_if(self, 0);
-
- /* Terminate only if the wakeup came from cancellation. */
- /* Otherwise ignore cancellation because we got the semaphore. */
-
- if (THREAD_GETMEM(self, p_woken_by_cancel)
- && THREAD_GETMEM(self, p_cancelstate) == PTHREAD_CANCEL_ENABLE) {
- THREAD_SETMEM(self, p_woken_by_cancel, 0);
- pthread_exit(PTHREAD_CANCELED);
- }
- /* We got the semaphore */
- return 0;
-}
-
-
-weak_alias (__new_sem_init, sem_init)
-weak_alias (__new_sem_wait, sem_wait)
-weak_alias (__new_sem_trywait, sem_trywait)
-weak_alias (__new_sem_post, sem_post)
-weak_alias (__new_sem_getvalue, sem_getvalue)
-weak_alias (__new_sem_destroy, sem_destroy)
-
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-22 03:37:37 +0000