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      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 (at) 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 }
    131