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-rw-r--r--nptl/pthread_cond_wait.c66
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diff --git a/nptl/pthread_cond_wait.c b/nptl/pthread_cond_wait.c
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+/* Copyright (C) 2002 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include "pthreadP.h"
+#include <lowlevellock.h>
+
+
+int
+pthread_cond_wait (cond, mutex)
+ pthread_cond_t *cond;
+ pthread_mutex_t *mutex;
+{
+ int err;
+
+ /* This function is a cancellation point. Test before we potentially
+ go to sleep. */
+ CANCELLATION_P (THREAD_SELF);
+
+ /* Make sure the condition is modified atomically. */
+ lll_mutex_lock (cond->__data.__lock);
+
+ /* Release the mutex. This might fail. */
+ err = pthread_mutex_unlock (mutex);
+ if (__builtin_expect (err != 0, 0))
+ {
+ lll_mutex_unlock (cond->__data.__lock);
+ return err;
+ }
+
+ /* One more tread waiting. */
+ ++cond->__data.__nr_sleepers;
+
+ /* The actual conditional variable implementation. */
+ lll_cond_wait (cond);
+
+ if (--cond->__data.__nr_sleepers == 0)
+ /* Forget about the current wakeups now that they are done. */
+ cond->__data.__nr_wakers = 0;
+
+ /* Lose the condvar lock. */
+ lll_mutex_unlock (cond->__data.__lock);
+
+ /* We have to get the mutex before returning. */
+ err = pthread_mutex_lock (mutex);
+
+ /* Cancellation handling. */
+ CANCELLATION_P (THREAD_SELF);
+
+ return err;
+}