lib/locks.h

   1 /*
   2  * Copyright (C) 2010-2012 Free Software Foundation, Inc.
   3  *
   4  * Author: Nikos Mavrogiannopoulos
   5  *
   6  * This file is part of GnuTLS.
   7  *
   8  * The GnuTLS is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public License
  10  * as published by the Free Software Foundation; either version 2.1 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This library is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public License
  19  * along with this program.  If not, see <http://www.gnu.org/licenses/>
  20  *
  21  */
  22
  23 #ifndef GNUTLS_LOCKS_H
  24 #define GNUTLS_LOCKS_H
  25
  26 #include <gnutls/gnutls.h>
  27 #include <gnutls_int.h>
  28 #include <system.h>
  29
  30 extern mutex_init_func gnutls_mutex_init;
  31 extern mutex_deinit_func gnutls_mutex_deinit;
  32 extern mutex_lock_func gnutls_mutex_lock;
  33 extern mutex_unlock_func gnutls_mutex_unlock;
  34
  35 #if defined(HAVE_WIN32_LOCKS)
  36 # include <windows.h>
  37
  38 /* Idea based based on comment 2 at:
  39  * http://stackoverflow.com/questions/3555859/is-it-possible-to-do-static-initialization-of-mutexes-in-windows
  40  */
  41 # define GNUTLS_STATIC_MUTEX(mutex) \
  42         static CRITICAL_SECTION *mutex = NULL
  43
  44 # define GNUTLS_STATIC_MUTEX_LOCK(mutex) \
  45         if (mutex == NULL) { \
  46                 CRITICAL_SECTION *mutex##tmp = malloc(sizeof(CRITICAL_SECTION)); \
  47                 InitializeCriticalSection(mutex##tmp); \
  48                 if (InterlockedCompareExchangePointer((PVOID*)&mutex, (PVOID)mutex##tmp, NULL) != NULL) { \
  49                         DeleteCriticalSection(mutex##tmp); \
  50                         free(mutex##tmp); \
  51                 } \
  52         } \
  53         EnterCriticalSection(mutex)
  54
  55 # define GNUTLS_STATIC_MUTEX_UNLOCK(mutex) \
  56         LeaveCriticalSection(mutex)
  57
  58 #elif defined(HAVE_PTHREAD_LOCKS)
  59 # include <pthread.h>
  60 # define GNUTLS_STATIC_MUTEX(mutex) \
  61         static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER
  62
  63 # define GNUTLS_STATIC_MUTEX_LOCK(mutex) \
  64         pthread_mutex_lock(&mutex)
  65
  66 # define GNUTLS_STATIC_MUTEX_UNLOCK(mutex) \
  67         pthread_mutex_unlock(&mutex)
  68
  69 #else
  70 # define GNUTLS_STATIC_MUTEX(mutex)
  71 # define GNUTLS_STATIC_MUTEX_LOCK(mutex)
  72 # define GNUTLS_STATIC_MUTEX_UNLOCK(mutex)
  73 #endif
  74
  75 #endif