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Diffstat (limited to 'pthreads/src/pthread_mutex_unlock.c')
| -rw-r--r-- | pthreads/src/pthread_mutex_unlock.c | 175 |
1 files changed, 175 insertions, 0 deletions
diff --git a/pthreads/src/pthread_mutex_unlock.c b/pthreads/src/pthread_mutex_unlock.c new file mode 100644 index 0000000..3d65d1a --- /dev/null +++ b/pthreads/src/pthread_mutex_unlock.c @@ -0,0 +1,175 @@ +/* + * pthread_mutex_unlock.c + * + * Description: + * This translation unit implements mutual exclusion (mutex) primitives. + * + * -------------------------------------------------------------------------- + * + * Pthreads-win32 - POSIX Threads Library for Win32 + * Copyright(C) 1998 John E. Bossom + * Copyright(C) 1999,2005 Pthreads-win32 contributors + * + * Contact Email: rpj@callisto.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 "pthread.h" +#include "implement.h" + + +int +pthread_mutex_unlock (pthread_mutex_t * mutex) +{ + int result = 0; + int kind; + pthread_mutex_t mx; + + /* + * Let the system deal with invalid pointers. + */ + + mx = *mutex; + + /* + * If the thread calling us holds the mutex then there is no + * race condition. If another thread holds the + * lock then we shouldn't be in here. + */ + if (mx < PTHREAD_ERRORCHECK_MUTEX_INITIALIZER) + { + kind = mx->kind; + + if (kind >= 0) + { + if (kind == PTHREAD_MUTEX_NORMAL) + { + LONG idx; + + idx = (LONG) PTW32_INTERLOCKED_EXCHANGE_LONG ((PTW32_INTERLOCKED_LONGPTR)&mx->lock_idx, + (PTW32_INTERLOCKED_LONG)0); + if (idx != 0) + { + if (idx < 0) + { + /* + * Someone may be waiting on that mutex. + */ + if (SetEvent (mx->event) == 0) + { + result = EINVAL; + } + } + } + } + else + { + if (pthread_equal (mx->ownerThread, pthread_self())) + { + if (kind != PTHREAD_MUTEX_RECURSIVE + || 0 == --mx->recursive_count) + { + mx->ownerThread.p = NULL; + + if ((LONG) PTW32_INTERLOCKED_EXCHANGE_LONG ((PTW32_INTERLOCKED_LONGPTR)&mx->lock_idx, + (PTW32_INTERLOCKED_LONG)0) < 0L) + { + /* Someone may be waiting on that mutex */ + if (SetEvent (mx->event) == 0) + { + result = EINVAL; + } + } + } + } + else + { + result = EPERM; + } + } + } + else + { + /* Robust types */ + pthread_t self = pthread_self(); + kind = -kind - 1; /* Convert to non-robust range */ + + /* + * The thread must own the lock regardless of type if the mutex + * is robust. + */ + if (pthread_equal (mx->ownerThread, self)) + { + PTW32_INTERLOCKED_COMPARE_EXCHANGE_LONG((PTW32_INTERLOCKED_LONGPTR) &mx->robustNode->stateInconsistent, + (PTW32_INTERLOCKED_LONG)PTW32_ROBUST_NOTRECOVERABLE, + (PTW32_INTERLOCKED_LONG)PTW32_ROBUST_INCONSISTENT); + if (PTHREAD_MUTEX_NORMAL == kind) + { + ptw32_robust_mutex_remove(mutex, NULL); + + if ((LONG) PTW32_INTERLOCKED_EXCHANGE_LONG((PTW32_INTERLOCKED_LONGPTR) &mx->lock_idx, + (PTW32_INTERLOCKED_LONG) 0) < 0) + { + /* + * Someone may be waiting on that mutex. + */ + if (SetEvent (mx->event) == 0) + { + result = EINVAL; + } + } + } + else + { + if (kind != PTHREAD_MUTEX_RECURSIVE + || 0 == --mx->recursive_count) + { + ptw32_robust_mutex_remove(mutex, NULL); + + if ((LONG) PTW32_INTERLOCKED_EXCHANGE_LONG((PTW32_INTERLOCKED_LONGPTR) &mx->lock_idx, + (PTW32_INTERLOCKED_LONG) 0) < 0) + { + /* + * Someone may be waiting on that mutex. + */ + if (SetEvent (mx->event) == 0) + { + result = EINVAL; + } + } + } + } + } + else + { + result = EPERM; + } + } + } + else if (mx != PTHREAD_MUTEX_INITIALIZER) + { + result = EINVAL; + } + + return (result); +} |