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-rw-r--r--libpthread/linuxthreads/condvar.c296
1 files changed, 0 insertions, 296 deletions
diff --git a/libpthread/linuxthreads/condvar.c b/libpthread/linuxthreads/condvar.c
deleted file mode 100644
index f9c46a331..000000000
--- a/libpthread/linuxthreads/condvar.c
+++ /dev/null
@@ -1,296 +0,0 @@
-/* Linuxthreads - a simple clone()-based implementation of Posix */
-/* threads for Linux. */
-/* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy@inria.fr) */
-/* and Pavel Krauz (krauz@fsid.cvut.cz). */
-/* */
-/* 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. */
-
-/* Condition variables */
-
-#include <errno.h>
-#include <sched.h>
-#include <stddef.h>
-#include <sys/time.h>
-#include "pthread.h"
-#include "internals.h"
-#include "spinlock.h"
-#include "queue.h"
-#include "restart.h"
-
-int pthread_cond_init(pthread_cond_t *cond,
- const pthread_condattr_t *cond_attr)
-{
- __pthread_init_lock(&cond->__c_lock);
- cond->__c_waiting = NULL;
- return 0;
-}
-
-int pthread_cond_destroy(pthread_cond_t *cond)
-{
- if (cond->__c_waiting != NULL) return EBUSY;
- return 0;
-}
-
-/* Function called by pthread_cancel to remove the thread from
- waiting on a condition variable queue. */
-
-static int cond_extricate_func(void *obj, pthread_descr th)
-{
- volatile pthread_descr self = thread_self();
- pthread_cond_t *cond = obj;
- int did_remove = 0;
-
- __pthread_lock(&cond->__c_lock, self);
- did_remove = remove_from_queue(&cond->__c_waiting, th);
- __pthread_unlock(&cond->__c_lock);
-
- return did_remove;
-}
-
-int pthread_cond_wait(pthread_cond_t *cond, pthread_mutex_t *mutex)
-{
- volatile pthread_descr self = thread_self();
- pthread_extricate_if extr;
- int already_canceled = 0;
- int spurious_wakeup_count;
-
- /* Check whether the mutex is locked and owned by this thread. */
- if (mutex->__m_kind != PTHREAD_MUTEX_TIMED_NP
- && mutex->__m_kind != PTHREAD_MUTEX_ADAPTIVE_NP
- && mutex->__m_owner != self)
- return EINVAL;
-
- /* Set up extrication interface */
- extr.pu_object = cond;
- extr.pu_extricate_func = cond_extricate_func;
-
- /* Register extrication interface */
- THREAD_SETMEM(self, p_condvar_avail, 0);
- __pthread_set_own_extricate_if(self, &extr);
-
- /* Atomically enqueue thread for waiting, but only if it is not
- canceled. If the thread is canceled, then it will fall through the
- suspend call below, and then call pthread_exit without
- having to worry about whether it is still on the condition variable queue.
- This depends on pthread_cancel setting p_canceled before calling the
- extricate function. */
-
- __pthread_lock(&cond->__c_lock, self);
- if (!(THREAD_GETMEM(self, p_canceled)
- && THREAD_GETMEM(self, p_cancelstate) == PTHREAD_CANCEL_ENABLE))
- enqueue(&cond->__c_waiting, self);
- else
- already_canceled = 1;
- __pthread_unlock(&cond->__c_lock);
-
- if (already_canceled) {
- __pthread_set_own_extricate_if(self, 0);
- pthread_exit(PTHREAD_CANCELED);
- }
-
- pthread_mutex_unlock(mutex);
-
- spurious_wakeup_count = 0;
- while (1)
- {
- suspend(self);
- if (THREAD_GETMEM(self, p_condvar_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);
-
- /* Check for cancellation again, to provide correct cancellation
- point behavior */
-
- 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_mutex_lock(mutex);
- pthread_exit(PTHREAD_CANCELED);
- }
-
- /* Put back any resumes we caught that don't belong to us. */
- while (spurious_wakeup_count--)
- restart(self);
-
- pthread_mutex_lock(mutex);
- return 0;
-}
-
-static int
-pthread_cond_timedwait_relative(pthread_cond_t *cond,
- pthread_mutex_t *mutex,
- const struct timespec * abstime)
-{
- volatile pthread_descr self = thread_self();
- int already_canceled = 0;
- pthread_extricate_if extr;
- int spurious_wakeup_count;
-
- /* Check whether the mutex is locked and owned by this thread. */
- if (mutex->__m_kind != PTHREAD_MUTEX_TIMED_NP
- && mutex->__m_kind != PTHREAD_MUTEX_ADAPTIVE_NP
- && mutex->__m_owner != self)
- return EINVAL;
-
- /* Set up extrication interface */
- extr.pu_object = cond;
- extr.pu_extricate_func = cond_extricate_func;
-
- /* Register extrication interface */
- THREAD_SETMEM(self, p_condvar_avail, 0);
- __pthread_set_own_extricate_if(self, &extr);
-
- /* Enqueue to wait on the condition and check for cancellation. */
- __pthread_lock(&cond->__c_lock, self);
- if (!(THREAD_GETMEM(self, p_canceled)
- && THREAD_GETMEM(self, p_cancelstate) == PTHREAD_CANCEL_ENABLE))
- enqueue(&cond->__c_waiting, self);
- else
- already_canceled = 1;
- __pthread_unlock(&cond->__c_lock);
-
- if (already_canceled) {
- __pthread_set_own_extricate_if(self, 0);
- pthread_exit(PTHREAD_CANCELED);
- }
-
- pthread_mutex_unlock(mutex);
-
- spurious_wakeup_count = 0;
- while (1)
- {
- if (!timedsuspend(self, abstime)) {
- int was_on_queue;
-
- /* __pthread_lock will queue back any spurious restarts that
- may happen to it. */
-
- __pthread_lock(&cond->__c_lock, self);
- was_on_queue = remove_from_queue(&cond->__c_waiting, self);
- __pthread_unlock(&cond->__c_lock);
-
- if (was_on_queue) {
- __pthread_set_own_extricate_if(self, 0);
- pthread_mutex_lock(mutex);
- return ETIMEDOUT;
- }
-
- /* Eat the outstanding restart() from the signaller */
- suspend(self);
- }
-
- if (THREAD_GETMEM(self, p_condvar_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);
-
- /* The remaining logic is the same as in other cancellable waits,
- such as pthread_join sem_wait or pthread_cond wait. */
-
- 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_mutex_lock(mutex);
- pthread_exit(PTHREAD_CANCELED);
- }
-
- /* Put back any resumes we caught that don't belong to us. */
- while (spurious_wakeup_count--)
- restart(self);
-
- pthread_mutex_lock(mutex);
- return 0;
-}
-
-int pthread_cond_timedwait(pthread_cond_t *cond, pthread_mutex_t *mutex,
- const struct timespec * abstime)
-{
- /* Indirect call through pointer! */
- return pthread_cond_timedwait_relative(cond, mutex, abstime);
-}
-
-int pthread_cond_signal(pthread_cond_t *cond)
-{
- pthread_descr th;
-
- __pthread_lock(&cond->__c_lock, NULL);
- th = dequeue(&cond->__c_waiting);
- __pthread_unlock(&cond->__c_lock);
- if (th != NULL) {
- th->p_condvar_avail = 1;
- WRITE_MEMORY_BARRIER();
- restart(th);
- }
- return 0;
-}
-
-int pthread_cond_broadcast(pthread_cond_t *cond)
-{
- pthread_descr tosignal, th;
-
- __pthread_lock(&cond->__c_lock, NULL);
- /* Copy the current state of the waiting queue and empty it */
- tosignal = cond->__c_waiting;
- cond->__c_waiting = NULL;
- __pthread_unlock(&cond->__c_lock);
- /* Now signal each process in the queue */
- while ((th = dequeue(&tosignal)) != NULL) {
- th->p_condvar_avail = 1;
- WRITE_MEMORY_BARRIER();
- restart(th);
- }
- return 0;
-}
-
-int pthread_condattr_init(pthread_condattr_t *attr)
-{
- return 0;
-}
-
-int pthread_condattr_destroy(pthread_condattr_t *attr)
-{
- return 0;
-}
-
-int pthread_condattr_getpshared (const pthread_condattr_t *attr, int *pshared)
-{
- *pshared = PTHREAD_PROCESS_PRIVATE;
- return 0;
-}
-
-int pthread_condattr_setpshared (pthread_condattr_t *attr, int pshared)
-{
- if (pshared != PTHREAD_PROCESS_PRIVATE && pshared != PTHREAD_PROCESS_SHARED)
- return EINVAL;
-
- /* For now it is not possible to shared a conditional variable. */
- if (pshared != PTHREAD_PROCESS_PRIVATE)
- return ENOSYS;
-
- return 0;
-}
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