diff options
Diffstat (limited to 'nptl/pthread_rwlock_timedrdlock.c')
| -rw-r--r-- | nptl/pthread_rwlock_timedrdlock.c | 137 |
1 files changed, 0 insertions, 137 deletions
diff --git a/nptl/pthread_rwlock_timedrdlock.c b/nptl/pthread_rwlock_timedrdlock.c deleted file mode 100644 index 80ea83a3dd..0000000000 --- a/nptl/pthread_rwlock_timedrdlock.c +++ /dev/null @@ -1,137 +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> - - -/* Try to acquire read lock for RWLOCK or return after specfied time. */ -int -pthread_rwlock_timedrdlock (rwlock, abstime) - pthread_rwlock_t *rwlock; - const struct timespec *abstime; -{ - int result = 0; - - /* Make sure we are along. */ - lll_mutex_lock(rwlock->__data.__lock); - - while (1) - { - int err; - - /* 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 (++rwlock->__data.__nr_readers == 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; - } - - /* Make sure the passed in timeout value is valid. Ideally this - test would be executed once. But since it must not be - performed if we would not block at all simply moving the test - to the front is no option. Replicating all the code is - costly while this test is not. */ - if (__builtin_expect (abstime->tv_nsec >= 1000000000 - || abstime->tv_nsec < 0, 0)) - { - result = EINVAL; - break; - } - - /* Get the current time. So far we support only one clock. */ - struct timeval tv; - (void) gettimeofday (&tv, NULL); - - /* Convert the absolute timeout value to a relative timeout. */ - struct timespec rt; - rt.tv_sec = abstime->tv_sec - tv.tv_sec; - rt.tv_nsec = abstime->tv_nsec - tv.tv_usec * 1000; - if (rt.tv_nsec < 0) - { - rt.tv_nsec += 1000000000; - --rt.tv_sec; - } - /* Did we already time out? */ - if (rt.tv_sec < 0) - { - /* Yep, return with an appropriate error. */ - result = ETIMEDOUT; - break; - } - - /* Remember that we are a reader. */ - if (++rwlock->__data.__nr_readers_queued == 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. */ - err = lll_futex_timed_wait (&rwlock->__data.__readers_wakeup, - waitval, &rt); - - /* Get the lock. */ - lll_mutex_lock (rwlock->__data.__lock); - - --rwlock->__data.__nr_readers_queued; - - /* Did the futex call time out? */ - if (err == -ETIMEDOUT) - { - /* Yep, report it. */ - result = ETIMEDOUT; - break; - } - } - - /* We are done, free the lock. */ - lll_mutex_unlock (rwlock->__data.__lock); - - return result; -} |