diff options
author | rpj <rpj> | 2002-02-23 02:08:22 +0000 |
---|---|---|
committer | rpj <rpj> | 2002-02-23 02:08:22 +0000 |
commit | 6b1e904f36dd621b2bcaf813a43dba8c836d20b3 (patch) | |
tree | a940ce963af51033d34ba4e31ea1d64c27d586a7 /pthread_rwlock_timedrdlock.c | |
parent | d2b870cd9b6d91261a304e156819571acc309b55 (diff) |
New functions from POSIX 1003.1 2001. Untested.
Diffstat (limited to 'pthread_rwlock_timedrdlock.c')
-rw-r--r-- | pthread_rwlock_timedrdlock.c | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/pthread_rwlock_timedrdlock.c b/pthread_rwlock_timedrdlock.c new file mode 100644 index 0000000..fb56548 --- /dev/null +++ b/pthread_rwlock_timedrdlock.c @@ -0,0 +1,105 @@ +/* + * pthread_rwlock_timedrdlock.c + * + * Description: + * This translation unit implements read/write lock primitives. + * + * -------------------------------------------------------------------------- + * + * Pthreads-win32 - POSIX Threads Library for Win32 + * Copyright(C) 1998 John E. Bossom + * Copyright(C) 1999,2002 Pthreads-win32 contributors + * + * Contact Email: rpj@ise.canberra.edu.au + * + * The current list of contributors is contained + * in the file CONTRIBUTORS included with the source + * code distribution. The list can also be seen at the + * following World Wide Web location: + * http://sources.redhat.com/pthreads-win32/contributors.html + * + * This 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 of the License, or (at your option) any later version. + * + * This 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 this library in the file COPYING.LIB; + * if not, write to the Free Software Foundation, Inc., + * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA + */ + +#include <errno.h> +#include <limits.h> + +#include "pthread.h" +#include "implement.h" + +int +pthread_rwlock_timedrdlock(pthread_rwlock_t *rwlock, const struct timespec * abstime) +{ + int result; + pthread_rwlock_t rwl; + + if (rwlock == NULL || *rwlock == NULL) + { + return EINVAL; + } + + /* + * We do a quick check to see if we need to do more work + * to initialise a static rwlock. We check + * again inside the guarded section of ptw32_rwlock_check_need_init() + * to avoid race conditions. + */ + if (*rwlock == PTHREAD_RWLOCK_INITIALIZER) + { + result = ptw32_rwlock_check_need_init(rwlock); + + if (result != 0 && result != EBUSY) + { + return result; + } + } + + rwl = *rwlock; + + if (rwl->nMagic != PTW32_RWLOCK_MAGIC) + { + return EINVAL; + } + + if ((result = pthread_mutex_timedlock(&(rwl->mtxExclusiveAccess), abstime)) != 0) + { + return result; + } + + if (++rwl->nSharedAccessCount == INT_MAX) + { + if ((result = pthread_mutex_timedlock(&(rwl->mtxSharedAccessCompleted), abstime)) != 0) + { + if (result == ETIMEDOUT) + { + ++rwl->nCompletedSharedAccessCount; + } + (void) pthread_mutex_unlock(&(rwl->mtxExclusiveAccess)); + return result; + } + + rwl->nSharedAccessCount -= rwl->nCompletedSharedAccessCount; + rwl->nCompletedSharedAccessCount = 0; + + if ((result = pthread_mutex_unlock(&(rwl->mtxSharedAccessCompleted))) != 0) + { + (void) pthread_mutex_unlock(&(rwl->mtxExclusiveAccess)); + return result; + } + } + + return (pthread_mutex_unlock(&(rwl->mtxExclusiveAccess))); +} |