Add support for config chain for interface modules

[vlc] / include / vlc_gcrypt.h

diff --git a/include/vlc_gcrypt.h b/include/vlc_gcrypt.h
index 8a654607c5ecf1e09fec79fc600e23f2074f4f1f..cd5ffd54572cefabaf9f07270041a4da4cc938f5 100644 (file)
--- a/include/vlc_gcrypt.h
+++ b/include/vlc_gcrypt.h
@@ -18,6 +18,11 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  *****************************************************************************/
 
+/**
+ * \file
+ * This file implements gcrypt support functions in vlc
+ */
+
 #ifdef LIBVLC_USE_PTHREAD
 /**
  * If possible, use gcrypt-provided thread implementation. This is so that
@@ -26,6 +31,7 @@
 GCRY_THREAD_OPTION_PTHREAD_IMPL;
 # define gcry_threads_vlc gcry_threads_pthread
 #else
+
 /**
  * gcrypt thread option VLC implementation
  */
@@ -66,7 +72,7 @@ static int gcry_vlc_mutex_unlock( void **lock )
     return VLC_SUCCESS;
 }
 
-static struct gcry_thread_cbs gcry_threads_vlc =
+static const struct gcry_thread_cbs gcry_threads_vlc =
 {
     GCRY_THREAD_OPTION_USER,
     NULL,
@@ -79,11 +85,22 @@ static struct gcry_thread_cbs gcry_threads_vlc =
 
 /**
  * Initializes gcrypt with proper locking.
- * @return VLC_SUCCESS on success, a VLC error code otherwise.
  */
 static inline void vlc_gcrypt_init (void)
 {
-    vlc_mutex_t *lock = var_AcquireMutex ("gcrypt_mutex");
-    gcry_control (GCRYCTL_SET_THREAD_CBS, &gcry_threads_vlc);
-    vlc_mutex_unlock (lock);
+    /* This would need a process-wide static mutex with all libraries linking
+     * to a given instance of libgcrypt. We cannot do this as we have different
+     * plugins linking with gcrypt, and some underlying libraries may use it
+     * behind our back. Only way is to always link gcrypt statically (ouch!) or
+     * have upstream gcrypt provide one shared object per threading system. */
+    static vlc_mutex_t lock = VLC_STATIC_MUTEX;
+    static bool done = false;
+
+    vlc_mutex_lock (&lock);
+    if (!done)
+    {
+        gcry_control (GCRYCTL_SET_THREAD_CBS, &gcry_threads_vlc);
+        done = true;
+    }
+    vlc_mutex_unlock (&lock);
 }