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      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 (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_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 */
    168