native_client_sdk/src/libraries/third_party/pthreads-win32/pthread_mutex_init.c

   1 /*
   2  * pthread_mutex_init.c
   3  *
   4  * Description:
   5  * This translation unit implements mutual exclusion (mutex) primitives.
   6  *
   7  * --------------------------------------------------------------------------
   8  *
   9  *      Pthreads-win32 - POSIX Threads Library for Win32
  10  *      Copyright(C) 1998 John E. Bossom
  11  *      Copyright(C) 1999,2005 Pthreads-win32 contributors
  12  *
  13  *      Contact Email: rpj@callisto.canberra.edu.au
  14  *
  15  *      The current list of contributors is contained
  16  *      in the file CONTRIBUTORS included with the source
  17  *      code distribution. The list can also be seen at the
  18  *      following World Wide Web location:
  19  *      http://sources.redhat.com/pthreads-win32/contributors.html
  20  *
  21  *      This library is free software; you can redistribute it and/or
  22  *      modify it under the terms of the GNU Lesser General Public
  23  *      License as published by the Free Software Foundation; either
  24  *      version 2 of the License, or (at your option) any later version.
  25  *
  26  *      This library is distributed in the hope that it will be useful,
  27  *      but WITHOUT ANY WARRANTY; without even the implied warranty of
  28  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  29  *      Lesser General Public License for more details.
  30  *
  31  *      You should have received a copy of the GNU Lesser General Public
  32  *      License along with this library in the file COPYING.LIB;
  33  *      if not, write to the Free Software Foundation, Inc.,
  34  *      59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  35  */
  36
  37 #include "pthread.h"
  38 #include "implement.h"
  39
  40
  41 int
  42 pthread_mutex_init (pthread_mutex_t * mutex, const pthread_mutexattr_t * attr)
  43 {
  44   int result = 0;
  45   pthread_mutex_t mx;
  46
  47   if (mutex == NULL)
  48     {
  49       return EINVAL;
  50     }
  51
  52   if (attr != NULL && *attr != NULL)
  53     {
  54       if ((*attr)->pshared == PTHREAD_PROCESS_SHARED)
  55         {
  56           /*
  57            * Creating mutex that can be shared between
  58            * processes.
  59            */
  60 #if _POSIX_THREAD_PROCESS_SHARED >= 0
  61
  62           /*
  63            * Not implemented yet.
  64            */
  65
  66 #error ERROR [__FILE__, line __LINE__]: Process shared mutexes are not supported yet.
  67
  68 #else
  69
  70           return ENOSYS;
  71
  72 #endif /* _POSIX_THREAD_PROCESS_SHARED */
  73         }
  74     }
  75
  76   mx = (pthread_mutex_t) calloc (1, sizeof (*mx));
  77
  78   if (mx == NULL)
  79     {
  80       result = ENOMEM;
  81     }
  82   else
  83     {
  84       mx->lock_idx = 0;
  85       mx->recursive_count = 0;
  86       mx->robustNode = NULL;
  87       if (attr == NULL || *attr == NULL)
  88         {
  89           mx->kind = PTHREAD_MUTEX_DEFAULT;
  90         }
  91       else
  92         {
  93           mx->kind = (*attr)->kind;
  94           if ((*attr)->robustness == PTHREAD_MUTEX_ROBUST)
  95             {
  96               /*
  97                * Use the negative range to represent robust types.
  98                * Replaces a memory fetch with a register negate and incr
  99                * in pthread_mutex_lock etc.
 100                *
 101                * Map 0,1,..,n to -1,-2,..,(-n)-1
 102                */
 103               mx->kind = -mx->kind - 1;
 104
 105               mx->robustNode = (ptw32_robust_node_t*) malloc(sizeof(ptw32_robust_node_t));
 106               mx->robustNode->stateInconsistent = PTW32_ROBUST_CONSISTENT;
 107               mx->robustNode->mx = mx;
 108               mx->robustNode->next = NULL;
 109               mx->robustNode->prev = NULL;
 110             }
 111         }
 112
 113       mx->ownerThread.p = NULL;
 114
 115       mx->event = CreateEvent (NULL, PTW32_FALSE,    /* manual reset = No */
 116                               PTW32_FALSE,           /* initial state = not signaled */
 117                               NULL);                 /* event name */
 118
 119       if (0 == mx->event)
 120         {
 121           result = ENOSPC;
 122           free (mx);
 123           mx = NULL;
 124         }
 125     }
 126
 127   *mutex = mx;
 128
 129   return (result);
 130 }