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authorJakub Jelinek <jakub@redhat.com>2007-07-31 13:33:18 +0000
committerJakub Jelinek <jakub@redhat.com>2007-07-31 13:33:18 +0000
commit32c075e1f01849e161724bbd400ba77244e482cc (patch)
tree5f083a3f352104f32bb6c902d57fa3f294bd8d4d /nptl/pthread_rwlock_rdlock.c
parentd6220e9ee38c1c9285221b023346201ec5f511b3 (diff)
downloadglibc-32c075e1f01849e161724bbd400ba77244e482cc.tar.gz
.
Diffstat (limited to 'nptl/pthread_rwlock_rdlock.c')
-rw-r--r--nptl/pthread_rwlock_rdlock.c95
1 files changed, 0 insertions, 95 deletions
diff --git a/nptl/pthread_rwlock_rdlock.c b/nptl/pthread_rwlock_rdlock.c
deleted file mode 100644
index e225d7030d..0000000000
--- a/nptl/pthread_rwlock_rdlock.c
+++ /dev/null
@@ -1,95 +0,0 @@
-/* Copyright (C) 2003, 2004 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>
-
-
-/* Acquire read lock for RWLOCK. */
-int
-__pthread_rwlock_rdlock (rwlock)
- pthread_rwlock_t *rwlock;
-{
- int result = 0;
-
- /* Make sure we are along. */
- lll_mutex_lock (rwlock->__data.__lock);
-
- while (1)
- {
- /* Get the rwlock if there is no writer... */
- if (rwlock->__data.__writer == 0
- /* ...and if either no writer is waiting or we prefer readers. */
- && (!rwlock->__data.__nr_writers_queued
- || rwlock->__data.__flags == 0))
- {
- /* Increment the reader counter. Avoid overflow. */
- if (__builtin_expect (++rwlock->__data.__nr_readers == 0, 0))
- {
- /* Overflow on number of readers. */
- --rwlock->__data.__nr_readers;
- result = EAGAIN;
- }
-
- break;
- }
-
- /* Make sure we are not holding the rwlock as a writer. This is
- a deadlock situation we recognize and report. */
- if (__builtin_expect (rwlock->__data.__writer
- == THREAD_GETMEM (THREAD_SELF, tid), 0))
- {
- result = EDEADLK;
- break;
- }
-
- /* Remember that we are a reader. */
- if (__builtin_expect (++rwlock->__data.__nr_readers_queued == 0, 0))
- {
- /* Overflow on number of queued readers. */
- --rwlock->__data.__nr_readers_queued;
- result = EAGAIN;
- break;
- }
-
- int waitval = rwlock->__data.__readers_wakeup;
-
- /* Free the lock. */
- lll_mutex_unlock (rwlock->__data.__lock);
-
- /* Wait for the writer to finish. */
- lll_futex_wait (&rwlock->__data.__readers_wakeup, waitval);
-
- /* Get the lock. */
- lll_mutex_lock (rwlock->__data.__lock);
-
- --rwlock->__data.__nr_readers_queued;
- }
-
- /* We are done, free the lock. */
- lll_mutex_unlock (rwlock->__data.__lock);
-
- return result;
-}
-
-weak_alias (__pthread_rwlock_rdlock, pthread_rwlock_rdlock)
-strong_alias (__pthread_rwlock_rdlock, __pthread_rwlock_rdlock_internal)