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Diffstat (limited to 'nptl/sysdeps/unix/sysv/solaris2/kopensolaris-gnu/rw_timedrdlock.c')
-rw-r--r--nptl/sysdeps/unix/sysv/solaris2/kopensolaris-gnu/rw_timedrdlock.c79
1 files changed, 79 insertions, 0 deletions
diff --git a/nptl/sysdeps/unix/sysv/solaris2/kopensolaris-gnu/rw_timedrdlock.c b/nptl/sysdeps/unix/sysv/solaris2/kopensolaris-gnu/rw_timedrdlock.c
new file mode 100644
index 0000000000..1fd5356f12
--- /dev/null
+++ b/nptl/sysdeps/unix/sysv/solaris2/kopensolaris-gnu/rw_timedrdlock.c
@@ -0,0 +1,79 @@
+/* Copyright (C) 2008 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by David Bartley <dtbartle@csclub.uwaterloo.ca>, 2008.
+
+ 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 <pthreadP.h>
+#include <synch.h>
+#include <abstime-to-reltime.h>
+
+
+int __rw_timedrdlock (rwlock, abstime)
+ rwlock_t *rwlock;
+ struct timespec *abstime;
+{
+ /* Reject invalid timeouts. */
+ if (INVALID_TIMESPEC (abstime))
+ return EINVAL;
+
+ struct timespec _reltime;
+ struct timespec *reltime = abstime_to_reltime (abstime, &_reltime);
+ if (reltime && reltime->tv_sec < 0)
+ return ETIME;
+
+ int errval = mutex_lock (&rwlock->mutex);
+ if (errval != 0)
+ return errval;
+
+ /* Check for deadlock. */
+ if (__builtin_expect (rwlock->owner == (uintptr_t)THREAD_SELF, 0) ||
+ ((rwlock->type & LOCK_SHARED) && __builtin_expect (
+ rwlock->ownerpid == THREAD_GETMEM (THREAD_SELF, pid), 0)))
+ {
+ (void)mutex_unlock (&rwlock->mutex);
+ return EDEADLK;
+ }
+
+ /* Wait until we can acquire the read lock. */
+ while ((rwlock->readers & _RWLOCK_WR_LOCK) ||
+ (__cond_has_waiters (&rwlock->writercv) &&
+ !PTHREAD_RWLOCK_PREFER_READER_P (rwlock)))
+ {
+ /* Wait for writer to wake us up. */
+ errval = __cond_reltimedwait_internal ((cond_t *)&rwlock->readercv,
+ (mutex_t *)&rwlock->mutex, reltime, 0);
+ if (errval != 0 && errval != EINTR)
+ {
+ (void)mutex_unlock (&rwlock->mutex);
+ return errval;
+ }
+ }
+
+ /* Increment readers (note that no other bits are set). */
+ if (rwlock->readers == _RWLOCK_RD_MAX)
+ {
+ /* XXX: Solaris mutexes have no overflow check and don't know about
+ EAGAIN; in practice overflow will not occur so we don't care. */
+ (void)mutex_unlock (&rwlock->mutex);
+ return EAGAIN;
+ }
+ ++rwlock->readers;
+
+ (void)mutex_unlock (&rwlock->mutex);
+ return 0;
+}