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-rw-r--r--linuxthreads/mutex.c362
1 files changed, 0 insertions, 362 deletions
diff --git a/linuxthreads/mutex.c b/linuxthreads/mutex.c
deleted file mode 100644
index d5f7a335cc..0000000000
--- a/linuxthreads/mutex.c
+++ /dev/null
@@ -1,362 +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. */
-
-/* Mutexes */
-
-#include <bits/libc-lock.h>
-#include <errno.h>
-#include <sched.h>
-#include <stddef.h>
-#include <limits.h>
-#include "pthread.h"
-#include "internals.h"
-#include "spinlock.h"
-#include "queue.h"
-#include "restart.h"
-
-int __pthread_mutex_init(pthread_mutex_t * mutex,
- const pthread_mutexattr_t * mutex_attr)
-{
- __pthread_init_lock(&mutex->__m_lock);
- mutex->__m_kind =
- mutex_attr == NULL ? PTHREAD_MUTEX_TIMED_NP : mutex_attr->__mutexkind;
- mutex->__m_count = 0;
- mutex->__m_owner = NULL;
- return 0;
-}
-strong_alias (__pthread_mutex_init, pthread_mutex_init)
-hidden_def (__pthread_mutex_init)
-
-int __pthread_mutex_destroy(pthread_mutex_t * mutex)
-{
- switch (mutex->__m_kind) {
- case PTHREAD_MUTEX_ADAPTIVE_NP:
- case PTHREAD_MUTEX_RECURSIVE_NP:
- if ((mutex->__m_lock.__status & 1) != 0)
- return EBUSY;
- return 0;
- case PTHREAD_MUTEX_ERRORCHECK_NP:
- case PTHREAD_MUTEX_TIMED_NP:
- if (mutex->__m_lock.__status != 0)
- return EBUSY;
- return 0;
- default:
- return EINVAL;
- }
-}
-strong_alias (__pthread_mutex_destroy, pthread_mutex_destroy)
-hidden_def (__pthread_mutex_destroy)
-
-int __pthread_mutex_trylock(pthread_mutex_t * mutex)
-{
- pthread_descr self;
- int retcode;
-
- switch(mutex->__m_kind) {
- case PTHREAD_MUTEX_ADAPTIVE_NP:
- retcode = __pthread_trylock(&mutex->__m_lock);
- return retcode;
- case PTHREAD_MUTEX_RECURSIVE_NP:
- self = thread_self();
- if (mutex->__m_owner == self) {
- mutex->__m_count++;
- return 0;
- }
- retcode = __pthread_trylock(&mutex->__m_lock);
- if (retcode == 0) {
- mutex->__m_owner = self;
- mutex->__m_count = 0;
- }
- return retcode;
- case PTHREAD_MUTEX_ERRORCHECK_NP:
- retcode = __pthread_alt_trylock(&mutex->__m_lock);
- if (retcode == 0) {
- mutex->__m_owner = thread_self();
- }
- return retcode;
- case PTHREAD_MUTEX_TIMED_NP:
- retcode = __pthread_alt_trylock(&mutex->__m_lock);
- return retcode;
- default:
- return EINVAL;
- }
-}
-strong_alias (__pthread_mutex_trylock, pthread_mutex_trylock)
-hidden_def (__pthread_mutex_trylock)
-
-int __pthread_mutex_lock(pthread_mutex_t * mutex)
-{
- pthread_descr self;
-
- switch(mutex->__m_kind) {
- case PTHREAD_MUTEX_ADAPTIVE_NP:
- __pthread_lock(&mutex->__m_lock, NULL);
- return 0;
- case PTHREAD_MUTEX_RECURSIVE_NP:
- self = thread_self();
- if (mutex->__m_owner == self) {
- mutex->__m_count++;
- return 0;
- }
- __pthread_lock(&mutex->__m_lock, self);
- mutex->__m_owner = self;
- mutex->__m_count = 0;
- return 0;
- case PTHREAD_MUTEX_ERRORCHECK_NP:
- self = thread_self();
- if (mutex->__m_owner == self) return EDEADLK;
- __pthread_alt_lock(&mutex->__m_lock, self);
- mutex->__m_owner = self;
- return 0;
- case PTHREAD_MUTEX_TIMED_NP:
- __pthread_alt_lock(&mutex->__m_lock, NULL);
- return 0;
- default:
- return EINVAL;
- }
-}
-strong_alias (__pthread_mutex_lock, pthread_mutex_lock)
-hidden_def (__pthread_mutex_lock)
-
-int __pthread_mutex_timedlock (pthread_mutex_t *mutex,
- const struct timespec *abstime)
-{
- pthread_descr self;
- int res;
-
- if (__builtin_expect (abstime->tv_nsec, 0) < 0
- || __builtin_expect (abstime->tv_nsec, 0) >= 1000000000)
- return EINVAL;
-
- switch(mutex->__m_kind) {
- case PTHREAD_MUTEX_ADAPTIVE_NP:
- __pthread_lock(&mutex->__m_lock, NULL);
- return 0;
- case PTHREAD_MUTEX_RECURSIVE_NP:
- self = thread_self();
- if (mutex->__m_owner == self) {
- mutex->__m_count++;
- return 0;
- }
- __pthread_lock(&mutex->__m_lock, self);
- mutex->__m_owner = self;
- mutex->__m_count = 0;
- return 0;
- case PTHREAD_MUTEX_ERRORCHECK_NP:
- self = thread_self();
- if (mutex->__m_owner == self) return EDEADLK;
- res = __pthread_alt_timedlock(&mutex->__m_lock, self, abstime);
- if (res != 0)
- {
- mutex->__m_owner = self;
- return 0;
- }
- return ETIMEDOUT;
- case PTHREAD_MUTEX_TIMED_NP:
- /* Only this type supports timed out lock. */
- return (__pthread_alt_timedlock(&mutex->__m_lock, NULL, abstime)
- ? 0 : ETIMEDOUT);
- default:
- return EINVAL;
- }
-}
-strong_alias (__pthread_mutex_timedlock, pthread_mutex_timedlock)
-
-int __pthread_mutex_unlock(pthread_mutex_t * mutex)
-{
- switch (mutex->__m_kind) {
- case PTHREAD_MUTEX_ADAPTIVE_NP:
- __pthread_unlock(&mutex->__m_lock);
- return 0;
- case PTHREAD_MUTEX_RECURSIVE_NP:
- if (mutex->__m_owner != thread_self())
- return EPERM;
- if (mutex->__m_count > 0) {
- mutex->__m_count--;
- return 0;
- }
- mutex->__m_owner = NULL;
- __pthread_unlock(&mutex->__m_lock);
- return 0;
- case PTHREAD_MUTEX_ERRORCHECK_NP:
- if (mutex->__m_owner != thread_self() || mutex->__m_lock.__status == 0)
- return EPERM;
- mutex->__m_owner = NULL;
- __pthread_alt_unlock(&mutex->__m_lock);
- return 0;
- case PTHREAD_MUTEX_TIMED_NP:
- __pthread_alt_unlock(&mutex->__m_lock);
- return 0;
- default:
- return EINVAL;
- }
-}
-strong_alias (__pthread_mutex_unlock, pthread_mutex_unlock)
-hidden_def (__pthread_mutex_unlock)
-
-int __pthread_mutexattr_init(pthread_mutexattr_t *attr)
-{
- attr->__mutexkind = PTHREAD_MUTEX_TIMED_NP;
- return 0;
-}
-strong_alias (__pthread_mutexattr_init, pthread_mutexattr_init)
-
-int __pthread_mutexattr_destroy(pthread_mutexattr_t *attr)
-{
- return 0;
-}
-strong_alias (__pthread_mutexattr_destroy, pthread_mutexattr_destroy)
-
-int __pthread_mutexattr_settype(pthread_mutexattr_t *attr, int kind)
-{
- if (kind != PTHREAD_MUTEX_ADAPTIVE_NP
- && kind != PTHREAD_MUTEX_RECURSIVE_NP
- && kind != PTHREAD_MUTEX_ERRORCHECK_NP
- && kind != PTHREAD_MUTEX_TIMED_NP)
- return EINVAL;
- attr->__mutexkind = kind;
- return 0;
-}
-weak_alias (__pthread_mutexattr_settype, pthread_mutexattr_settype)
-strong_alias ( __pthread_mutexattr_settype, __pthread_mutexattr_setkind_np)
-weak_alias (__pthread_mutexattr_setkind_np, pthread_mutexattr_setkind_np)
-
-int __pthread_mutexattr_gettype(const pthread_mutexattr_t *attr, int *kind)
-{
- *kind = attr->__mutexkind;
- return 0;
-}
-weak_alias (__pthread_mutexattr_gettype, pthread_mutexattr_gettype)
-strong_alias (__pthread_mutexattr_gettype, __pthread_mutexattr_getkind_np)
-weak_alias (__pthread_mutexattr_getkind_np, pthread_mutexattr_getkind_np)
-
-int __pthread_mutexattr_getpshared (const pthread_mutexattr_t *attr,
- int *pshared)
-{
- *pshared = PTHREAD_PROCESS_PRIVATE;
- return 0;
-}
-weak_alias (__pthread_mutexattr_getpshared, pthread_mutexattr_getpshared)
-
-int __pthread_mutexattr_setpshared (pthread_mutexattr_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;
-}
-weak_alias (__pthread_mutexattr_setpshared, pthread_mutexattr_setpshared)
-
-/* Once-only execution */
-
-static pthread_mutex_t once_masterlock = PTHREAD_MUTEX_INITIALIZER;
-static pthread_cond_t once_finished = PTHREAD_COND_INITIALIZER;
-static int fork_generation = 0; /* Child process increments this after fork. */
-
-enum { NEVER = 0, IN_PROGRESS = 1, DONE = 2 };
-
-/* If a thread is canceled while calling the init_routine out of
- pthread once, this handler will reset the once_control variable
- to the NEVER state. */
-
-static void pthread_once_cancelhandler(void *arg)
-{
- pthread_once_t *once_control = arg;
-
- pthread_mutex_lock(&once_masterlock);
- *once_control = NEVER;
- pthread_mutex_unlock(&once_masterlock);
- pthread_cond_broadcast(&once_finished);
-}
-
-int __pthread_once(pthread_once_t * once_control, void (*init_routine)(void))
-{
- /* flag for doing the condition broadcast outside of mutex */
- int state_changed;
-
- /* Test without locking first for speed */
- if (*once_control == DONE) {
- READ_MEMORY_BARRIER();
- return 0;
- }
- /* Lock and test again */
-
- state_changed = 0;
-
- pthread_mutex_lock(&once_masterlock);
-
- /* If this object was left in an IN_PROGRESS state in a parent
- process (indicated by stale generation field), reset it to NEVER. */
- if ((*once_control & 3) == IN_PROGRESS && (*once_control & ~3) != fork_generation)
- *once_control = NEVER;
-
- /* If init_routine is being called from another routine, wait until
- it completes. */
- while ((*once_control & 3) == IN_PROGRESS) {
- pthread_cond_wait(&once_finished, &once_masterlock);
- }
- /* Here *once_control is stable and either NEVER or DONE. */
- if (*once_control == NEVER) {
- *once_control = IN_PROGRESS | fork_generation;
- pthread_mutex_unlock(&once_masterlock);
- pthread_cleanup_push(pthread_once_cancelhandler, once_control);
- init_routine();
- pthread_cleanup_pop(0);
- pthread_mutex_lock(&once_masterlock);
- WRITE_MEMORY_BARRIER();
- *once_control = DONE;
- state_changed = 1;
- }
- pthread_mutex_unlock(&once_masterlock);
-
- if (state_changed)
- pthread_cond_broadcast(&once_finished);
-
- return 0;
-}
-strong_alias (__pthread_once, pthread_once)
-
-/*
- * Handle the state of the pthread_once mechanism across forks. The
- * once_masterlock is acquired in the parent process prior to a fork to ensure
- * that no thread is in the critical region protected by the lock. After the
- * fork, the lock is released. In the child, the lock and the condition
- * variable are simply reset. The child also increments its generation
- * counter which lets pthread_once calls detect stale IN_PROGRESS states
- * and reset them back to NEVER.
- */
-
-void __pthread_once_fork_prepare(void)
-{
- pthread_mutex_lock(&once_masterlock);
-}
-
-void __pthread_once_fork_parent(void)
-{
- pthread_mutex_unlock(&once_masterlock);
-}
-
-void __pthread_once_fork_child(void)
-{
- pthread_mutex_init(&once_masterlock, NULL);
- pthread_cond_init(&once_finished, NULL);
- if (fork_generation <= INT_MAX - 4)
- fork_generation += 4; /* leave least significant two bits zero */
- else
- fork_generation = 0;
-}
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