| /* |
| * pthread_mutex_destroy.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_destroy (pthread_mutex_t * mutex) |
| { |
| int result = 0; |
| pthread_mutex_t mx; |
| |
| /* |
| * Let the system deal with invalid pointers. |
| */ |
| |
| /* |
| * Check to see if we have something to delete. |
| */ |
| if (*mutex < PTHREAD_ERRORCHECK_MUTEX_INITIALIZER) |
| { |
| mx = *mutex; |
| |
| result = pthread_mutex_trylock (&mx); |
| |
| /* |
| * If trylock succeeded and the mutex is not recursively locked it |
| * can be destroyed. |
| */ |
| if (0 == result || ENOTRECOVERABLE == result) |
| { |
| if (mx->kind != PTHREAD_MUTEX_RECURSIVE || 1 == mx->recursive_count) |
| { |
| /* |
| * FIXME!!! |
| * The mutex isn't held by another thread but we could still |
| * be too late invalidating the mutex below since another thread |
| * may already have entered mutex_lock and the check for a valid |
| * *mutex != NULL. |
| */ |
| *mutex = NULL; |
| |
| result = (0 == result)?pthread_mutex_unlock(&mx):0; |
| |
| if (0 == result) |
| { |
| if (mx->robustNode != NULL) |
| { |
| free(mx->robustNode); |
| } |
| if (!CloseHandle (mx->event)) |
| { |
| *mutex = mx; |
| result = EINVAL; |
| } |
| else |
| { |
| free (mx); |
| } |
| } |
| else |
| { |
| /* |
| * Restore the mutex before we return the error. |
| */ |
| *mutex = mx; |
| } |
| } |
| else /* mx->recursive_count > 1 */ |
| { |
| /* |
| * The mutex must be recursive and already locked by us (this thread). |
| */ |
| mx->recursive_count--; /* Undo effect of pthread_mutex_trylock() above */ |
| result = EBUSY; |
| } |
| } |
| } |
| else |
| { |
| ptw32_mcs_local_node_t node; |
| |
| /* |
| * See notes in ptw32_mutex_check_need_init() above also. |
| */ |
| |
| ptw32_mcs_lock_acquire(&ptw32_mutex_test_init_lock, &node); |
| |
| /* |
| * Check again. |
| */ |
| if (*mutex >= PTHREAD_ERRORCHECK_MUTEX_INITIALIZER) |
| { |
| /* |
| * This is all we need to do to destroy a statically |
| * initialised mutex that has not yet been used (initialised). |
| * If we get to here, another thread |
| * waiting to initialise this mutex will get an EINVAL. |
| */ |
| *mutex = NULL; |
| } |
| else |
| { |
| /* |
| * The mutex has been initialised while we were waiting |
| * so assume it's in use. |
| */ |
| result = EBUSY; |
| } |
| ptw32_mcs_lock_release(&node); |
| } |
| |
| return (result); |
| } |