/* * pthread_key_create.c * * Description: * POSIX thread functions which implement thread-specific data (TSD). * * -------------------------------------------------------------------------- * *      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., *      59 Temple Place - Suite 330, Boston, MA 02111-1307, USA */#include "pthread.h"#include "implement.h"/* TLS_OUT_OF_INDEXES not defined on WinCE */#ifndef TLS_OUT_OF_INDEXES#define TLS_OUT_OF_INDEXES 0xffffffff#endifintpthread_key_create (pthread_key_t * key, void (*destructor) (void *))     /*      * ------------------------------------------------------      * DOCPUBLIC      *      This function creates a thread-specific data key visible      *      to all threads. All existing and new threads have a value      *      NULL for key until set using pthread_setspecific. When any      *      thread with a non-NULL value for key terminates, 'destructor'      *      is called with key's current value for that thread.      *      * PARAMETERS      *      key      *              pointer to an instance of pthread_key_t      *      *      * DESCRIPTION      *      This function creates a thread-specific data key visible      *      to all threads. All existing and new threads have a value      *      NULL for key until set using pthread_setspecific. When any      *      thread with a non-NULL value for key terminates, 'destructor'      *      is called with key's current value for that thread.      *      * RESULTS      *              0               successfully created semaphore,      *              EAGAIN          insufficient resources or PTHREAD_KEYS_MAX      *                              exceeded,      *              ENOMEM          insufficient memory to create the key,      *      * ------------------------------------------------------      */{  int result = 0;  pthread_key_t newkey;  if ((newkey = (pthread_key_t) calloc (1, sizeof (*newkey))) == NULL)    {      result = ENOMEM;    }  else if ((newkey->key = TlsAlloc ()) == TLS_OUT_OF_INDEXES)    {      result = EAGAIN;      free (newkey);      newkey = NULL;    }  else if (destructor != NULL)    {      /*       * Have to manage associations between thread and key;       * Therefore, need a lock that allows multiple threads       * to gain exclusive access to the key->threads list.       *       * The mutex will only be created when it is first locked.       */      newkey->keyLock = PTHREAD_MUTEX_INITIALIZER;      newkey->destructor = destructor;    }  *key = newkey;  return (result);}