codec/avcodec/va.{c,h}: Initialize/terminate libva only once.

Initialize/terminate libva only once. VAAPI calls are now being used by
2 modules which only have interaction with each other through vlc core.
Both modules (codec and vout) can be initiated independently they should
not call vaIntialize (or vaTerminate) one after each other (or simultanously).

modules/codec/avcodec/va.c

@@ -47,7 +47,7 @@
 #ifdef HAVE_AVCODEC_VAAPI
 
 /* Global VAAPI connection state */
-static vlc_va_conn_t vlc_va_conn = { 0, 0, 0, 0 };
+static vlc_va_conn_t vlc_va_conn = { NULL, 0, 0, 0, 0 };
 
 static vlc_va_conn_t *vlc_va_get_conn( void )
 {
@@ -76,6 +76,7 @@ int vlc_va_Initialize( vlc_va_conn_t *conn, const char *display_name )
     if( vaInitialize(conn->p_display, &conn->i_version_major, &conn->i_version_minor) )
         goto error;
 
+    conn->i_ref_count++;
     b_va_inited = true;
     return VLC_SUCCESS;
 
@@ -83,4 +84,19 @@ error:
     return VLC_EGENERIC;
 }
 
+void vlc_va_Terminate( vlc_va_conn_t *conn )
+{
+    conn->i_ref_count--;
+    if (conn->i_ref_count <= 0)
+    {
+        if( conn->p_display )
+            vaTerminate( conn->p_display );
+        if( conn->p_display_x11 )
+            XCloseDisplay( conn->p_display_x11 );
+
+        conn->p_display = 0;
+        conn->p_display_x11 = NULL;
+    }
+}
+
 #endif

modules/codec/avcodec/va.h

@@ -69,9 +69,11 @@ struct vlc_va_conn_t
     VADisplay     p_display;
     int           i_version_major;
     int           i_version_minor;
+    int           i_ref_count; /* for internal use only */
 };
 
 int vlc_va_Initialize(vlc_va_conn_t *conn, const char *display_name);
+void vlc_va_Terminate(vlc_va_conn_t *conn);
 #endif
 
 #endif