lua: implement timers in vlc.misc

modules/misc/lua/libs/misc.c

@@ -6,6 +6,7 @@
  *
  * Authors: Antoine Cellerier <dionoea at videolan tod org>
  *          Pierre d'Herbemont <pdherbemont # videolan.org>
+ *          Rémi Duraffort <ivoire # videolan tod org>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -243,6 +244,91 @@ static int vlclua_action_id( lua_State *L )
     return 1;
 }
 
+/*****************************************************************************
+ * Timer functions
+ *****************************************************************************/
+static int vlclua_timer_schedule( lua_State *L );
+
+static const luaL_Reg vlclua_timer_reg[] = {
+    { "schedule",   vlclua_timer_schedule },
+    { NULL,         NULL                  }
+};
+
+typedef struct
+{
+    lua_State *L;
+    vlc_timer_t timer;
+    char *psz_callback;
+} vlclua_timer_t;
+
+static int vlclua_timer_schedule( lua_State *L )
+{
+    vlclua_timer_t **pp_timer = (vlclua_timer_t**)luaL_checkudata( L, 1, "timer" );
+    if( !pp_timer || !*pp_timer )
+        luaL_error( L, "Can't get pointer to timer" );
+
+    bool b_relative = luaL_checkboolean( L, 2 );
+    mtime_t i_value = luaL_checkinteger( L, 3 );
+    mtime_t i_interval = luaL_checkinteger( L, 4 );
+
+    vlc_timer_schedule( (*pp_timer)->timer, b_relative, i_value, i_interval );
+    return 0;
+}
+
+static void vlclua_timer_callback( void *data )
+{
+    vlclua_timer_t *p_timer = (vlclua_timer_t*)data;
+    lua_State *L = p_timer->L;
+
+    lua_getglobal( L, p_timer->psz_callback );
+    if( lua_pcall( L, 0, 0, 0 ) )
+    {
+        const char *psz_err = lua_tostring( L, -1 );
+        fprintf( stderr, "Error while running the timer callback: %s\n", psz_err );
+        lua_settop( L, 0 );
+    }
+}
+
+static int vlclua_timer_delete( lua_State *L )
+{
+    vlclua_timer_t **pp_timer = (vlclua_timer_t**)luaL_checkudata( L, 1, "timer" );
+    if( !pp_timer || !*pp_timer )
+        luaL_error( L, "Can't get pointer to timer" );
+
+    vlc_timer_destroy( (*pp_timer)->timer );
+    free( (*pp_timer)->psz_callback );
+    return 0;
+}
+
+static int vlclua_timer_create( lua_State *L )
+{
+    vlclua_timer_t *p_timer = malloc( sizeof( vlclua_timer_t ) );
+    if( !lua_isstring( L, 1 ) )
+        return luaL_error( L, "timer(function_name)" );
+
+    if( vlc_timer_create( &p_timer->timer, vlclua_timer_callback, p_timer ) )
+        return luaL_error( L, "Cannot initialize the timer" );
+
+    p_timer->L = L;
+    p_timer->psz_callback = strdup( luaL_checkstring( L, 1 ) );
+
+    vlclua_timer_t **pp_timer = lua_newuserdata( L, sizeof( vlclua_timer_t* ) );
+    *pp_timer = p_timer;
+
+    /* Create the object */
+    if( luaL_newmetatable( L, "timer" ) )
+    {
+        lua_newtable( L );
+        luaL_register( L, NULL, vlclua_timer_reg );
+        lua_setfield( L, -2, "__index" );
+        lua_pushcfunction( L, vlclua_timer_delete );
+        lua_setfield( L, -2, "__gc" );
+    }
+    lua_setmetatable( L, -2 );
+
+    return 1;
+}
+
 /*****************************************************************************
  *
  *****************************************************************************/
@@ -268,6 +354,8 @@ static const luaL_Reg vlclua_misc_reg[] = {
     { "should_die", vlclua_intf_should_die },
     { "quit", vlclua_quit },
 
+    { "timer", vlclua_timer_create },
+
     { NULL, NULL }
 };