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

   1 /*
   2  * pthread_setspecific.c
   3  *
   4  * Description:
   5  * POSIX thread functions which implement thread-specific data (TSD).
   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_setspecific (pthread_key_t key, const void *value)
  43      /*
  44       * ------------------------------------------------------
  45       * DOCPUBLIC
  46       *      This function sets the value of the thread specific
  47       *      key in the calling thread.
  48       *
  49       * PARAMETERS
  50       *      key
  51       *              an instance of pthread_key_t
  52       *      value
  53       *              the value to set key to
  54       *
  55       *
  56       * DESCRIPTION
  57       *      This function sets the value of the thread specific
  58       *      key in the calling thread.
  59       *
  60       * RESULTS
  61       *              0               successfully set value
  62       *              EAGAIN          could not set value
  63       *              ENOENT          SERIOUS!!
  64       *
  65       * ------------------------------------------------------
  66       */
  67 {
  68   pthread_t self;
  69   int result = 0;
  70
  71   if (key != ptw32_selfThreadKey)
  72     {
  73       /*
  74        * Using pthread_self will implicitly create
  75        * an instance of pthread_t for the current
  76        * thread if one wasn't explicitly created
  77        */
  78       self = pthread_self ();
  79       if (self.p == NULL)
  80         {
  81           return ENOENT;
  82         }
  83     }
  84   else
  85     {
  86       /*
  87        * Resolve catch-22 of registering thread with selfThread
  88        * key
  89        */
  90       ptw32_thread_t * sp = (ptw32_thread_t *) pthread_getspecific (ptw32_selfThreadKey);
  91
  92       if (sp == NULL)
  93         {
  94           if (value == NULL)
  95             {
  96               return ENOENT;
  97             }
  98           self = *((pthread_t *) value);
  99         }
 100       else
 101         {
 102           self = sp->ptHandle;
 103         }
 104     }
 105
 106   result = 0;
 107
 108   if (key != NULL)
 109     {
 110       if (self.p != NULL && key->destructor != NULL && value != NULL)
 111         {
 112           ptw32_mcs_local_node_t keyLock;
 113           ptw32_mcs_local_node_t threadLock;
 114           ptw32_thread_t * sp = (ptw32_thread_t *) self.p;
 115           /*
 116            * Only require associations if we have to
 117            * call user destroy routine.
 118            * Don't need to locate an existing association
 119            * when setting data to NULL for WIN32 since the
 120            * data is stored with the operating system; not
 121            * on the association; setting assoc to NULL short
 122            * circuits the search.
 123            */
 124           ThreadKeyAssoc *assoc;
 125
 126           ptw32_mcs_lock_acquire(&(key->keyLock), &keyLock);
 127           ptw32_mcs_lock_acquire(&(sp->threadLock), &threadLock);
 128
 129           assoc = (ThreadKeyAssoc *) sp->keys;
 130           /*
 131            * Locate existing association
 132            */
 133           while (assoc != NULL)
 134             {
 135               if (assoc->key == key)
 136                 {
 137                   /*
 138                    * Association already exists
 139                    */
 140                   break;
 141                 }
 142                 assoc = assoc->nextKey;
 143             }
 144
 145           /*
 146            * create an association if not found
 147            */
 148           if (assoc == NULL)
 149             {
 150               result = ptw32_tkAssocCreate (sp, key);
 151             }
 152
 153           ptw32_mcs_lock_release(&threadLock);
 154           ptw32_mcs_lock_release(&keyLock);
 155         }
 156
 157       if (result == 0)
 158         {
 159           if (!TlsSetValue (key->key, (LPVOID) value))
 160             {
 161               result = EAGAIN;
 162             }
 163         }
 164     }
 165
 166   return (result);
 167 }                               /* pthread_setspecific */