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pthreads/pthread_cond.c /dev/null Libc-391
--- /dev/null
+++ Libc/Libc-391/pthreads/pthread_cond.c
@@ -0,0 +1,577 @@
+/*
+ * Copyright (c) 2000-2003 Apple Computer, Inc. All rights reserved.
+ *
+ * @APPLE_LICENSE_HEADER_START@
+ * 
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this
+ * file.
+ * 
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ * 
+ * @APPLE_LICENSE_HEADER_END@
+ */
+/*
+ * Copyright 1996 1995 by Open Software Foundation, Inc. 1997 1996 1995 1994 1993 1992 1991  
+ *              All Rights Reserved 
+ *  
+ * Permission to use, copy, modify, and distribute this software and 
+ * its documentation for any purpose and without fee is hereby granted,
+ * provided that the above copyright notice appears in all copies and 
+ * that both the copyright notice and this permission notice appear in 
+ * supporting documentation. 
+ *  
+ * OSF DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE 
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 
+ * FOR A PARTICULAR PURPOSE. 
+ *  
+ * IN NO EVENT SHALL OSF BE LIABLE FOR ANY SPECIAL, INDIRECT, OR 
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM 
+ * LOSS OF USE, DATA OR PROFITS, WHETHER IN ACTION OF CONTRACT, 
+ * NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION 
+ * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 
+ */
+/*
+ * MkLinux
+ */
+
+/*
+ * POSIX Pthread Library
+ */
+
+#include "pthread_internals.h"
+#include <sys/time.h>              /* For struct timespec and getclock(). */
+#include <stdio.h>
+    
+extern void _pthread_mutex_remove(pthread_mutex_t *, pthread_t);
+extern int __unix_conforming;
+
+#ifndef BUILDING_VARIANT /* [ */
+
+/*
+ * Destroy a condition variable.
+ */
+int       
+pthread_cond_destroy(pthread_cond_t *cond)
+{
+	int ret;
+	int sig = cond->sig;
+
+	/* to provide backwards compat for apps using united condtn vars */
+	if((sig != _PTHREAD_COND_SIG) && (sig !=_PTHREAD_COND_SIG_init))
+		return(EINVAL);
+
+	LOCK(cond->lock);
+	if (cond->sig == _PTHREAD_COND_SIG)
+	{
+		if (cond->busy == (pthread_mutex_t *)NULL)
+		{
+			cond->sig = _PTHREAD_NO_SIG;
+			ret = ESUCCESS;
+		} else
+			ret = EBUSY;
+	} else
+		ret = EINVAL; /* Not an initialized condition variable structure */
+	UNLOCK(cond->lock);
+	return (ret);
+}
+
+/*
+ * Initialize a condition variable.  Note: 'attr' is ignored.
+ */
+static int       
+_pthread_cond_init(pthread_cond_t *cond,
+		  const pthread_condattr_t *attr)
+{
+	cond->next = (pthread_cond_t *)NULL;
+	cond->prev = (pthread_cond_t *)NULL;
+	cond->busy = (pthread_mutex_t *)NULL;
+	cond->waiters = 0;
+	cond->sigspending = 0;
+	cond->sem = SEMAPHORE_NULL;
+	cond->sig = _PTHREAD_COND_SIG;
+	return (ESUCCESS);
+}
+
+/*
+ * Initialize a condition variable.  This is the public interface.
+ * We can't trust the lock, so initialize it first before taking
+ * it.
+ */
+int       
+pthread_cond_init(pthread_cond_t *cond,
+		  const pthread_condattr_t *attr)
+{
+	LOCK_INIT(cond->lock);
+	return (_pthread_cond_init(cond, attr));
+}
+
+/*
+ * Signal a condition variable, waking up all threads waiting for it.
+ */
+int       
+pthread_cond_broadcast(pthread_cond_t *cond)
+{
+	kern_return_t kern_res;
+	semaphore_t sem;
+	int sig = cond->sig;
+
+	/* to provide backwards compat for apps using united condtn vars */
+	if((sig != _PTHREAD_COND_SIG) && (sig !=_PTHREAD_COND_SIG_init))
+		return(EINVAL);
+
+	LOCK(cond->lock);
+	if (cond->sig != _PTHREAD_COND_SIG)
+	{
+		int res;
+
+		if (cond->sig == _PTHREAD_COND_SIG_init)
+		{
+			_pthread_cond_init(cond, NULL);
+			res = ESUCCESS;
+		} else 
+			res = EINVAL;  /* Not a condition variable */
+		UNLOCK(cond->lock);
+		return (res);
+	}
+	else if ((sem = cond->sem) == SEMAPHORE_NULL)
+	{
+		/* Avoid kernel call since there are no waiters... */
+		UNLOCK(cond->lock);
+		return (ESUCCESS);
+	}
+	cond->sigspending++;
+	UNLOCK(cond->lock);
+
+	PTHREAD_MACH_CALL(semaphore_signal_all(sem), kern_res);
+
+	LOCK(cond->lock);
+	cond->sigspending--;
+	if (cond->waiters == 0 && cond->sigspending == 0)
+	{
+		cond->sem = SEMAPHORE_NULL;
+		restore_sem_to_pool(sem);
+	}
+	UNLOCK(cond->lock);
+	if (kern_res != KERN_SUCCESS)
+		return (EINVAL);
+	return (ESUCCESS);
+}
+
+/*
+ * Signal a condition variable, waking a specified thread.
+ */
+int       
+pthread_cond_signal_thread_np(pthread_cond_t *cond, pthread_t thread)
+{
+	kern_return_t kern_res;
+	semaphore_t sem;
+	int sig = cond->sig;
+
+	/* to provide backwards compat for apps using united condtn vars */
+	if((sig != _PTHREAD_COND_SIG) && (sig !=_PTHREAD_COND_SIG_init))
+		return(EINVAL);
+
+	LOCK(cond->lock);
+	if (cond->sig != _PTHREAD_COND_SIG)
+	{
+		int ret;
+
+		if (cond->sig == _PTHREAD_COND_SIG_init) 
+		{
+			_pthread_cond_init(cond, NULL);
+			ret = ESUCCESS;
+		}
+		else
+			ret = EINVAL; /* Not a condition variable */
+		UNLOCK(cond->lock);
+		return (ret);
+	}
+	else if ((sem = cond->sem) == SEMAPHORE_NULL)
+	{
+		/* Avoid kernel call since there are not enough waiters... */
+		UNLOCK(cond->lock);
+		return (ESUCCESS);
+	}
+	cond->sigspending++;
+	UNLOCK(cond->lock);
+
+	if (thread == (pthread_t)NULL)
+	{
+		kern_res = semaphore_signal_thread(sem, THREAD_NULL);
+		if (kern_res == KERN_NOT_WAITING)
+			kern_res = KERN_SUCCESS;
+	}
+	else if (thread->sig == _PTHREAD_SIG)
+	{
+	        PTHREAD_MACH_CALL(semaphore_signal_thread(
+			sem, pthread_mach_thread_np(thread)), kern_res);
+	}
+	else
+		kern_res = KERN_FAILURE;
+
+	LOCK(cond->lock);
+	cond->sigspending--;
+	if (cond->waiters == 0 && cond->sigspending == 0)
+	{
+		cond->sem = SEMAPHORE_NULL;
+		restore_sem_to_pool(sem);
+	}
+	UNLOCK(cond->lock);
+	if (kern_res != KERN_SUCCESS)
+		return (EINVAL);
+	return (ESUCCESS);
+}
+
+/*
+ * Signal a condition variable, waking only one thread.
+ */
+int
+pthread_cond_signal(pthread_cond_t *cond)
+{
+	return pthread_cond_signal_thread_np(cond, NULL);
+}
+
+/*
+ * Manage a list of condition variables associated with a mutex
+ */
+
+static void
+_pthread_cond_add(pthread_cond_t *cond, pthread_mutex_t *mutex)
+{
+	pthread_cond_t *c;
+	LOCK(mutex->lock);
+	if ((c = mutex->busy) != (pthread_cond_t *)NULL)
+	{
+		c->prev = cond;
+	} 
+	cond->next = c;
+	cond->prev = (pthread_cond_t *)NULL;
+	mutex->busy = cond;
+	UNLOCK(mutex->lock);
+	if (cond->sem == SEMAPHORE_NULL)
+		cond->sem = new_sem_from_pool();
+}
+
+static void
+_pthread_cond_remove(pthread_cond_t *cond, pthread_mutex_t *mutex)
+{
+	pthread_cond_t *n, *p;
+
+	LOCK(mutex->lock);
+	if ((n = cond->next) != (pthread_cond_t *)NULL)
+	{
+		n->prev = cond->prev;
+	}
+	if ((p = cond->prev) != (pthread_cond_t *)NULL)
+	{
+		p->next = cond->next;
+	} 
+	else
+	{ /* This is the first in the list */
+		mutex->busy = n;
+	}
+	UNLOCK(mutex->lock);
+	if (cond->sigspending == 0)
+	{
+		restore_sem_to_pool(cond->sem);
+		cond->sem = SEMAPHORE_NULL;
+	}
+}
+
+static void cond_cleanup(void *arg)
+{
+    pthread_cond_t *cond = (pthread_cond_t *)arg;
+    pthread_mutex_t *mutex;
+    LOCK(cond->lock);
+    mutex = cond->busy;
+    cond->waiters--;
+    if (cond->waiters == 0) {
+        _pthread_cond_remove(cond, mutex);
+        cond->busy = (pthread_mutex_t *)NULL;
+    }
+    UNLOCK(cond->lock);
+    /*
+    ** Can't do anything if this fails -- we're on the way out
+    */
+    (void)pthread_mutex_lock(mutex);
+}
+
+/*
+ * Suspend waiting for a condition variable.
+ * Note: we have to keep a list of condition variables which are using
+ * this same mutex variable so we can detect invalid 'destroy' sequences.
+ */
+__private_extern__ int       
+_pthread_cond_wait(pthread_cond_t *cond, 
+		   pthread_mutex_t *mutex,
+		   const struct timespec *abstime,
+		   int isRelative,
+		    int isconforming)
+{
+	int res;
+	kern_return_t kern_res;
+	int wait_res;
+	pthread_mutex_t *busy;
+	mach_timespec_t then;
+	struct timespec cthen = {0,0};
+	int sig = cond->sig;
+
+	/* to provide backwards compat for apps using united condtn vars */
+	if((sig != _PTHREAD_COND_SIG) && (sig !=_PTHREAD_COND_SIG_init))
+		return(EINVAL);
+	LOCK(cond->lock);
+	if (cond->sig != _PTHREAD_COND_SIG)
+	{
+		if (cond->sig != _PTHREAD_COND_SIG_init)
+		{
+			UNLOCK(cond->lock);
+			return (EINVAL);        /* Not a condition variable */
+		}
+		_pthread_cond_init(cond, NULL);
+	}
+
+	if (abstime) {
+		if (!isconforming)
+		{
+			if (isRelative == 0) {
+				struct timespec now;
+				struct timeval tv;
+				gettimeofday(&tv, NULL);
+				TIMEVAL_TO_TIMESPEC(&tv, &now);
+
+				/* Compute relative time to sleep */
+				then.tv_nsec = abstime->tv_nsec - now.tv_nsec;
+				then.tv_sec = abstime->tv_sec - now.tv_sec;
+				if (then.tv_nsec < 0)
+				{
+					then.tv_nsec += NSEC_PER_SEC;
+					then.tv_sec--;
+				}
+				if (((int)then.tv_sec < 0) ||
+					((then.tv_sec == 0) && (then.tv_nsec == 0)))
+				{
+					UNLOCK(cond->lock);
+					return ETIMEDOUT;
+				}
+			} else {
+				then.tv_sec = abstime->tv_sec;
+				then.tv_nsec = abstime->tv_nsec;
+			}
+			if (then.tv_nsec >= NSEC_PER_SEC) {
+				UNLOCK(cond->lock);
+				return EINVAL;
+			}
+		} else {
+			cthen.tv_sec = abstime->tv_sec;
+            cthen.tv_nsec = abstime->tv_nsec;
+            if ((cthen.tv_sec < 0) || (cthen.tv_nsec < 0)) {
+                UNLOCK(cond->lock);
+                return EINVAL;
+            }
+            if (cthen.tv_nsec >= NSEC_PER_SEC) {
+                UNLOCK(cond->lock);
+                return EINVAL;
+            }
+        }
+	}
+
+	if (++cond->waiters == 1)
+	{
+		_pthread_cond_add(cond, mutex);
+		cond->busy = mutex;
+	}
+	else if ((busy = cond->busy) != mutex)
+	{
+		/* Must always specify the same mutex! */
+		cond->waiters--;
+		UNLOCK(cond->lock);
+		return (EINVAL);
+	}
+	UNLOCK(cond->lock);
+	
+#if defined(DEBUG)
+	_pthread_mutex_remove(mutex, pthread_self());
+#endif
+	LOCK(mutex->lock);
+	if (--mutex->lock_count == 0)
+	{
+		if (mutex->sem == SEMAPHORE_NULL)
+			mutex->sem = new_sem_from_pool();
+		mutex->owner = _PTHREAD_MUTEX_OWNER_SWITCHING;
+		UNLOCK(mutex->lock);
+
+		if (!isconforming) {
+			if (abstime) {
+				kern_res = semaphore_timedwait_signal(cond->sem, mutex->sem, then);
+			} else {
+				PTHREAD_MACH_CALL(semaphore_wait_signal(cond->sem, mutex->sem), kern_res);
+			}
+		} else {
+            pthread_cleanup_push(cond_cleanup, (void *)cond);
+            wait_res = __semwait_signal(cond->sem, mutex->sem, abstime != NULL, isRelative,
+			cthen.tv_sec, cthen.tv_nsec);
+            pthread_cleanup_pop(0);
+		}
+	} else {
+		UNLOCK(mutex->lock);
+		if (!isconforming) {
+			if (abstime) {
+				kern_res = semaphore_timedwait(cond->sem, then);
+			} else {
+				PTHREAD_MACH_CALL(semaphore_wait(cond->sem), kern_res);
+			}
+		 } else {
+				pthread_cleanup_push(cond_cleanup, (void *)cond);
+                wait_res = __semwait_signal(cond->sem, NULL, abstime != NULL, isRelative,
+			cthen.tv_sec, cthen.tv_nsec);
+                pthread_cleanup_pop(0);
+		}
+
+	}
+
+	LOCK(cond->lock);
+	cond->waiters--;
+	if (cond->waiters == 0)
+	{
+		_pthread_cond_remove(cond, mutex);
+		cond->busy = (pthread_mutex_t *)NULL;
+	}
+	UNLOCK(cond->lock);
+	if ((res = pthread_mutex_lock(mutex)) != ESUCCESS)
+		return (res);
+
+	if (!isconforming) {
+		/* KERN_ABORTED can be treated as a spurious wakeup */
+		if ((kern_res == KERN_SUCCESS) || (kern_res == KERN_ABORTED))
+			return (ESUCCESS);
+		else if (kern_res == KERN_OPERATION_TIMED_OUT)
+			return (ETIMEDOUT);
+		return (EINVAL);
+	} else {
+    	if (wait_res < 0) {
+			if (errno == ETIMEDOUT) {
+				return ETIMEDOUT;
+			} else if (errno == EINTR) {
+				/*
+				**  EINTR can be treated as a spurious wakeup unless we were canceled.
+				*/
+				return 0;	
+				}
+			return EINVAL;
+    	}
+    	return 0;
+	}
+}
+
+
+int       
+pthread_cond_timedwait_relative_np(pthread_cond_t *cond, 
+		       pthread_mutex_t *mutex,
+		       const struct timespec *abstime)
+{
+	return (_pthread_cond_wait(cond, mutex, abstime, 1, 0));
+}
+
+int
+pthread_condattr_init(pthread_condattr_t *attr)
+{
+        attr->sig = _PTHREAD_COND_ATTR_SIG;
+        return (ESUCCESS);
+}
+
+int       
+pthread_condattr_destroy(pthread_condattr_t *attr)
+{
+        attr->sig = _PTHREAD_NO_SIG;  /* Uninitialized */
+        return (ESUCCESS);
+}
+
+int
+pthread_condattr_getpshared(const pthread_condattr_t *attr,
+				int *pshared)
+{
+        if (attr->sig == _PTHREAD_COND_ATTR_SIG)
+        {
+                *pshared = (int)PTHREAD_PROCESS_PRIVATE;
+                return (ESUCCESS);
+        } else
+        {
+                return (EINVAL); /* Not an initialized 'attribute' structure */
+        }
+}
+
+
+int
+pthread_condattr_setpshared(pthread_condattr_t * attr, int pshared)
+{
+        if (attr->sig == _PTHREAD_COND_ATTR_SIG)
+        {
+                if ( pshared == PTHREAD_PROCESS_PRIVATE)
+                {
+			/* attr->pshared = pshared */
+                        return (ESUCCESS);
+                } else
+                {
+                        return (EINVAL); /* Invalid parameter */
+                }
+        } else
+        {
+                return (EINVAL); /* Not an initialized 'attribute' structure */
+        }
+
+}
+
+#else /* !BUILDING_VARIANT */
+extern int _pthread_cond_wait(pthread_cond_t *cond, 
+			pthread_mutex_t *mutex,
+			const struct timespec *abstime,
+			int isRelative,
+			int isconforming);
+
+#endif /* !BUILDING_VARIANT ] */
+
+int       
+pthread_cond_wait(pthread_cond_t *cond, 
+		  pthread_mutex_t *mutex)
+{
+	int conforming;
+#if __DARWIN_UNIX03
+
+	if (__unix_conforming == 0)
+		__unix_conforming = 1;
+
+	conforming = 1;
+#else /* __DARWIN_UNIX03 */
+	conforming = 0;
+#endif /* __DARWIN_UNIX03 */
+	return (_pthread_cond_wait(cond, mutex, (struct timespec *)NULL, 0, conforming));
+}
+
+int       
+pthread_cond_timedwait(pthread_cond_t *cond, 
+		       pthread_mutex_t *mutex,
+		       const struct timespec *abstime)
+{
+	int conforming;
+#if __DARWIN_UNIX03
+	if (__unix_conforming == 0)
+		__unix_conforming = 1;
+
+        conforming = 1;
+#else /* __DARWIN_UNIX03 */
+        conforming = 0;
+#endif /* __DARWIN_UNIX03 */
+
+	return (_pthread_cond_wait(cond, mutex, abstime, 0, conforming));
+}
+