obs-studio/deps/w32-pthreads/pthread_mutex_init.c

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2013-09-30 19:37:13 -07:00
/*
* pthread_mutex_init.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.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
2013-09-30 19:37:13 -07:00
*/
#include "pthread.h"
#include "implement.h"
int
pthread_mutex_init (pthread_mutex_t * mutex, const pthread_mutexattr_t * attr)
{
int result = 0;
pthread_mutex_t mx;
if (mutex == NULL)
{
return EINVAL;
}
if (attr != NULL && *attr != NULL)
{
if ((*attr)->pshared == PTHREAD_PROCESS_SHARED)
{
/*
* Creating mutex that can be shared between
* processes.
*/
#if _POSIX_THREAD_PROCESS_SHARED >= 0
/*
* Not implemented yet.
*/
#error ERROR [__FILE__, line __LINE__]: Process shared mutexes are not supported yet.
#else
return ENOSYS;
#endif /* _POSIX_THREAD_PROCESS_SHARED */
}
}
mx = (pthread_mutex_t) calloc (1, sizeof (*mx));
if (mx == NULL)
{
result = ENOMEM;
}
else
{
mx->lock_idx = 0;
mx->recursive_count = 0;
mx->robustNode = NULL;
if (attr == NULL || *attr == NULL)
{
mx->kind = PTHREAD_MUTEX_DEFAULT;
}
else
{
mx->kind = (*attr)->kind;
if ((*attr)->robustness == PTHREAD_MUTEX_ROBUST)
{
/*
* Use the negative range to represent robust types.
* Replaces a memory fetch with a register negate and incr
* in pthread_mutex_lock etc.
*
* Map 0,1,..,n to -1,-2,..,(-n)-1
*/
mx->kind = -mx->kind - 1;
mx->robustNode = (ptw32_robust_node_t*) malloc(sizeof(ptw32_robust_node_t));
mx->robustNode->stateInconsistent = PTW32_ROBUST_CONSISTENT;
mx->robustNode->mx = mx;
mx->robustNode->next = NULL;
mx->robustNode->prev = NULL;
}
}
mx->ownerThread.p = NULL;
mx->event = CreateEvent (NULL, PTW32_FALSE, /* manual reset = No */
PTW32_FALSE, /* initial state = not signaled */
NULL); /* event name */
if (0 == mx->event)
{
result = ENOSPC;
free (mx);
mx = NULL;
}
}
*mutex = mx;
return (result);
}