obs-studio/deps/w32-pthreads/pthread_key_create.c

109 lines
3.7 KiB
C

/*
* 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.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
*/
#include "pthread.h"
#include "implement.h"
/* TLS_OUT_OF_INDEXES not defined on WinCE */
#if !defined(TLS_OUT_OF_INDEXES)
#define TLS_OUT_OF_INDEXES 0xffffffff
#endif
int
pthread_key_create (pthread_key_t * key, void (PTW32_CDECL *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 competing threads
* to gain exclusive access to the key->threads list.
*
* The mutex will only be created when it is first locked.
*/
newkey->keyLock = 0;
newkey->destructor = destructor;
}
*key = newkey;
return (result);
}