include/vlc_gcrypt.h

   1 /*****************************************************************************
   2  * vlc_gcrypt.h: VLC thread support for gcrypt
   3  *****************************************************************************
   4  * Copyright (C) 2004-2008 Rémi Denis-Courmont
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  19  *****************************************************************************/
  20
  21 #ifdef LIBVLC_USE_PTHREAD
  22 /**
  23  * If possible, use gcrypt-provided thread implementation. This is so that
  24  * other non-VLC components (inside the process) can also use gcrypt safely.
  25  */
  26 GCRY_THREAD_OPTION_PTHREAD_IMPL;
  27 # define gcry_threads_vlc gcry_threads_pthread
  28 #else
  29 /**
  30  * gcrypt thread option VLC implementation
  31  */
  32
  33 static int gcry_vlc_mutex_init( void **p_sys )
  34 {
  35     int i_val;
  36     vlc_mutex_t *p_lock = (vlc_mutex_t *)malloc( sizeof( vlc_mutex_t ) );
  37
  38     if( p_lock == NULL)
  39         return ENOMEM;
  40
  41     i_val = vlc_mutex_init( p_lock );
  42     if( i_val )
  43         free( p_lock );
  44     else
  45         *p_sys = p_lock;
  46     return i_val;
  47 }
  48
  49 static int gcry_vlc_mutex_destroy( void **p_sys )
  50 {
  51     vlc_mutex_t *p_lock = (vlc_mutex_t *)*p_sys;
  52     vlc_mutex_destroy( p_lock );
  53     free( p_lock );
  54     return VLC_SUCCESS;
  55 }
  56
  57 static int gcry_vlc_mutex_lock( void **p_sys )
  58 {
  59     vlc_mutex_lock( (vlc_mutex_t *)*p_sys );
  60     return VLC_SUCCESS;
  61 }
  62
  63 static int gcry_vlc_mutex_unlock( void **lock )
  64 {
  65     vlc_mutex_unlock( (vlc_mutex_t *)*lock );
  66     return VLC_SUCCESS;
  67 }
  68
  69 static struct gcry_thread_cbs gcry_threads_vlc =
  70 {
  71     GCRY_THREAD_OPTION_USER,
  72     NULL,
  73     gcry_vlc_mutex_init,
  74     gcry_vlc_mutex_destroy,
  75     gcry_vlc_mutex_lock,
  76     gcry_vlc_mutex_unlock
  77 };
  78 #endif
  79
  80 /**
  81  * Initializes gcrypt with proper locking.
  82  */
  83 static inline void vlc_gcrypt_init (void)
  84 {
  85     vlc_mutex_t *lock = var_AcquireMutex ("gcrypt_mutex");
  86     gcry_control (GCRYCTL_SET_THREAD_CBS, &gcry_threads_vlc);
  87     vlc_mutex_unlock (lock);
  88 }