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Diffstat (limited to 'nptl/sysdeps/pthread/pthread_rwlock_unlock.c')
-rw-r--r--nptl/sysdeps/pthread/pthread_rwlock_unlock.c57
1 files changed, 57 insertions, 0 deletions
diff --git a/nptl/sysdeps/pthread/pthread_rwlock_unlock.c b/nptl/sysdeps/pthread/pthread_rwlock_unlock.c
new file mode 100644
index 0000000000..9cae8b6c22
--- /dev/null
+++ b/nptl/sysdeps/pthread/pthread_rwlock_unlock.c
@@ -0,0 +1,57 @@
+/* Copyright (C) 2003 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Martin Schwidefsky <schwidefsky@de.ibm.com>, 2003.
+
+   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 <errno.h>
+#include <sysdep.h>
+#include <lowlevellock.h>
+#include <pthread.h>
+#include <pthreadP.h>
+
+/* Unlock RWLOCK.  */
+int
+__pthread_rwlock_unlock (pthread_rwlock_t *rwlock)
+{
+  lll_mutex_lock (rwlock->__data.__lock);
+  if (rwlock->__data.__writer)
+    rwlock->__data.__writer = 0;
+  else
+    --rwlock->__data.__nr_readers;
+  if (rwlock->__data.__nr_readers == 0)
+    {
+      if (rwlock->__data.__nr_writers_queued)
+	{
+	  ++rwlock->__data.__writer_wakeup;
+	  lll_mutex_unlock (rwlock->__data.__lock);
+	  lll_futex_wake (&rwlock->__data.__writer_wakeup, 1);
+	  return 0;
+	}
+      else if (rwlock->__data.__nr_readers_queued)
+	{
+	  ++rwlock->__data.__readers_wakeup;
+	  lll_mutex_unlock (rwlock->__data.__lock);
+	  lll_futex_wake (&rwlock->__data.__readers_wakeup, INT_MAX);
+	  return 0;
+	}
+    }
+  lll_mutex_unlock (rwlock->__data.__lock);
+  return 0;
+}
+
+weak_alias (__pthread_rwlock_unlock, pthread_rwlock_unlock)
+strong_alias (__pthread_rwlock_unlock, __pthread_rwlock_unlock_internal)