When scanning multiple lua scripts, create a new lua_State for each script....

When scanning multiple lua scripts, create a new lua_State for each script. This will prevent data corruption from a previous script affecting subsequent scripts.

modules/misc/lua/demux.c

@@ -116,18 +116,36 @@ static const luaL_Reg p_reg_parse[] =
  * the script pointed by psz_filename.
  *****************************************************************************/
 static int probe_luascript( vlc_object_t *p_this, const char * psz_filename,
-                            lua_State * L, void * user_data )
+                            void * user_data )
 {
     VLC_UNUSED(user_data);
     demux_t * p_demux = (demux_t *)p_this;
 
     p_demux->p_sys->psz_filename = strdup(psz_filename);
 
-    /* In lua, setting a variable's value to nil is equivalent to deleting it */
-    lua_pushnil( L );
-    lua_pushnil( L );
-    lua_setglobal( L, "probe" );
-    lua_setglobal( L, "parse" );
+    /* Initialise Lua state structure */
+    lua_State *L = luaL_newstate();
+    if( !L )
+    {
+        msg_Err( p_demux, "Could not create new Lua State" );
+        goto error;
+    }
+    p_demux->p_sys->L = L;
+
+    /* Load Lua libraries */
+    luaL_openlibs( L ); /* FIXME: Don't open all the libs? */
+
+    luaL_register( L, "vlc", p_reg );
+    luaopen_msg( L );
+    luaopen_strings( L );
+    lua_pushlightuserdata( L, p_demux );
+    lua_setfield( L, -2, "private" );
+    lua_pushstring( L, p_demux->psz_path );
+    lua_setfield( L, -2, "path" );
+    lua_pushstring( L, p_demux->psz_access );
+    lua_setfield( L, -2, "access" );
+
+    lua_pop( L, 1 );
 
     /* Load and run the script(s) */
     if( luaL_dofile( L, psz_filename ) )
@@ -167,6 +185,8 @@ static int probe_luascript( vlc_object_t *p_this, const char * psz_filename,
 
 error:
     lua_pop( L, 1 );
+    lua_close( p_demux->p_sys->L );
+    p_demux->p_sys->L = NULL;
     FREENULL( p_demux->p_sys->psz_filename );
     return VLC_EGENERIC;
 }
@@ -191,33 +211,8 @@ int Import_LuaPlaylist( vlc_object_t *p_this )
     p_demux->pf_control = Control;
     p_demux->pf_demux = Demux;
 
-    /* Initialise Lua state structure */
-    L = luaL_newstate();
-    if( !L )
-    {
-        msg_Err( p_demux, "Could not create new Lua State" );
-        free( p_demux->p_sys );
-        return VLC_EGENERIC;
-    }
-    p_demux->p_sys->L = L;
-
-    /* Load Lua libraries */
-    luaL_openlibs( L ); /* FIXME: Don't open all the libs? */
-
-    luaL_register( L, "vlc", p_reg );
-    luaopen_msg( L );
-    luaopen_strings( L );
-    lua_pushlightuserdata( L, p_demux );
-    lua_setfield( L, -2, "private" );
-    lua_pushstring( L, p_demux->psz_path );
-    lua_setfield( L, -2, "path" );
-    lua_pushstring( L, p_demux->psz_access );
-    lua_setfield( L, -2, "access" );
-
-    lua_pop( L, 1 );
-
     ret = vlclua_scripts_batch_execute( p_this, "playlist",
-                                        &probe_luascript, L, NULL );
+                                        &probe_luascript, NULL );
     if( ret )
         Close_LuaPlaylist( p_this );
     return ret;
@@ -230,7 +225,8 @@ int Import_LuaPlaylist( vlc_object_t *p_this )
 void Close_LuaPlaylist( vlc_object_t *p_this )
 {
     demux_t *p_demux = (demux_t *)p_this;
-    lua_close( p_demux->p_sys->L );
+    if( p_demux->p_sys->L )
+        lua_close( p_demux->p_sys->L );
     free( p_demux->p_sys->psz_filename );
     free( p_demux->p_sys );
 }

modules/misc/lua/extension.c

@@ -54,7 +54,7 @@ const char* const ppsz_capabilities[] = {
 
 static int ScanExtensions( extensions_manager_t *p_this );
 static int ScanLuaCallback( vlc_object_t *p_this, const char *psz_script,
-                            lua_State *L, void *pb_continue );
+                            void *pb_continue );
 static int Control( extensions_manager_t *, int, va_list );
 static int GetMenuEntries( extensions_manager_t *p_mgr, extension_t *p_ext,
                     char ***pppsz_titles, uint16_t **ppi_ids );
@@ -99,15 +99,6 @@ int Open_Extension( vlc_object_t *p_this )
     vlc_mutex_init( &p_mgr->lock );
     vlc_mutex_init( &p_mgr->p_sys->lock );
 
-    /* Initialise Lua state structure */
-    lua_State *L = GetLuaState( p_mgr, NULL );
-    if( !L )
-    {
-        free( p_sys );
-        return VLC_EGENERIC;
-    }
-    p_sys->L = L;
-
     /* Scan available Lua Extensions */
     if( ScanExtensions( p_mgr ) != VLC_SUCCESS )
     {
@@ -115,9 +106,6 @@ int Open_Extension( vlc_object_t *p_this )
         return VLC_EGENERIC;
     }
 
-    lua_close( L );
-    p_sys->L = NULL;
-
     // Create the dialog-event variable
     var_Create( p_this, "dialog-event", VLC_VAR_ADDRESS );
     var_AddCallback( p_this, "dialog-event",
@@ -153,9 +141,6 @@ void Close_Extension( vlc_object_t *p_this )
     msg_Dbg( p_mgr, "All extensions are now deactivated" );
     ARRAY_RESET( p_mgr->p_sys->activated_extensions );
 
-    if( p_mgr->p_sys && p_mgr->p_sys->L )
-        lua_close( p_mgr->p_sys->L );
-
     vlc_mutex_destroy( &p_mgr->lock );
     vlc_mutex_destroy( &p_mgr->p_sys->lock );
     free( p_mgr->p_sys );
@@ -199,7 +184,7 @@ static int ScanExtensions( extensions_manager_t *p_mgr )
         vlclua_scripts_batch_execute( VLC_OBJECT( p_mgr ),
                                       "extensions",
                                       &ScanLuaCallback,
-                                      p_mgr->p_sys->L, &b_true );
+                                      &b_true );
 
     if( !i_ret )
         return VLC_EGENERIC;
@@ -215,7 +200,7 @@ static int ScanExtensions( extensions_manager_t *p_mgr )
  * @param pb_continue bool* that indicates whether to continue batch or not
  **/
 int ScanLuaCallback( vlc_object_t *p_this, const char *psz_script,
-                     lua_State *L, void *pb_continue )
+                     void *pb_continue )
 {
     extensions_manager_t *p_mgr = ( extensions_manager_t* ) p_this;
     bool b_ok = false;
@@ -250,6 +235,7 @@ int ScanLuaCallback( vlc_object_t *p_this, const char *psz_script,
     vlc_cond_init( &p_ext->p_sys->wait );
 
     /* Load and run the script(s) */
+    lua_State *L = luaL_newstate();
     if( luaL_dofile( L, psz_script ) )
     {
         msg_Warn( p_mgr, "Error loading script %s: %s", psz_script,
@@ -414,6 +400,7 @@ int ScanLuaCallback( vlc_object_t *p_this, const char *psz_script,
 
     b_ok = true;
 exit:
+    lua_close( L );
     if( !b_ok )
     {
         free( p_ext->psz_name );

modules/misc/lua/extension.h

@@ -48,9 +48,6 @@ struct extensions_manager_sys_t
     /* Lock for this list */
     vlc_mutex_t lock;
 
-    /* Lua specific */
-    lua_State *L;
-
     /* Flag indicating that the module is about to be unloaded */
     bool b_killed;
 };

modules/misc/lua/meta.c

@@ -126,14 +126,19 @@ error:
  * pointed by psz_filename.
  *****************************************************************************/
 static int fetch_art( vlc_object_t *p_this, const char * psz_filename,
-                      lua_State * L, void * user_data )
+                      void * user_data )
 {
-    input_item_t * p_input = user_data;
+    input_item_t * p_item = user_data;
     int s;
 
+    lua_State *L = init( p_this, p_item );
+
     int i_ret = run(p_this, psz_filename, L, "fetch_art");
     if(i_ret != VLC_SUCCESS)
+    {
+        lua_close( L );
         return i_ret;
+    }
 
     if((s = lua_gettop( L )))
     {
@@ -145,7 +150,8 @@ static int fetch_art( vlc_object_t *p_this, const char * psz_filename,
             if( psz_value && *psz_value != 0 )
             {
                 lua_Dbg( p_this, "setting arturl: %s", psz_value );
-                input_item_SetArtURL ( p_input, psz_value );
+                input_item_SetArtURL ( p_item, psz_value );
+                lua_close( L );
                 return VLC_SUCCESS;
             }
         }
@@ -160,6 +166,7 @@ static int fetch_art( vlc_object_t *p_this, const char * psz_filename,
         msg_Err( p_this, "Script went completely foobar" );
     }
 
+    lua_close( L );
     return VLC_EGENERIC;
 }
 
@@ -168,15 +175,20 @@ static int fetch_art( vlc_object_t *p_this, const char * psz_filename,
  * pointed by psz_filename.
  *****************************************************************************/
 static int read_meta( vlc_object_t *p_this, const char * psz_filename,
-                     lua_State * L, void * user_data )
+                      void * user_data )
 {
-    VLC_UNUSED(user_data);
+    input_item_t * p_item = user_data;
+    lua_State *L = init( p_this, p_item );
 
     int i_ret = run(p_this, psz_filename, L, "read_meta");
     if(i_ret != VLC_SUCCESS)
+    {
+        lua_close( L );
         return i_ret;
+    }
 
     // Continue, all "meta reader" are always run.
+    lua_close( L );
     return 1;
 }
 
@@ -186,11 +198,15 @@ static int read_meta( vlc_object_t *p_this, const char * psz_filename,
  * pointed by psz_filename.
  *****************************************************************************/
 static int fetch_meta( vlc_object_t *p_this, const char * psz_filename,
-                     lua_State * L, void * user_data )
+                       void * user_data )
 {
-    VLC_UNUSED(user_data);
+    input_item_t * p_item = user_data;
+    lua_State *L = init( p_this, p_item );
+
+    int ret = run(p_this, psz_filename, L, "fetch_meta");
+    lua_close( L );
 
-    return run(p_this, psz_filename, L, "fetch_meta");
+    return ret;
 }
 
 /*****************************************************************************
@@ -202,9 +218,7 @@ int ReadMeta( vlc_object_t *p_this )
     demux_meta_t *p_demux_meta = (demux_meta_t *)p_this;
     input_item_t *p_item = p_demux_meta->p_item;
 
-    lua_State *L = init( p_this, p_item );
-    int i_ret = vlclua_scripts_batch_execute( p_this, "meta/reader", &read_meta, L, NULL );
-    lua_close( L );
+    int i_ret = vlclua_scripts_batch_execute( p_this, "meta/reader", &read_meta, p_item );
 
     return i_ret;
 }
@@ -219,9 +233,7 @@ int FetchMeta( vlc_object_t *p_this )
     demux_meta_t *p_demux_meta = (demux_meta_t *)p_this;
     input_item_t *p_item = p_demux_meta->p_item;
 
-    lua_State *L = init( p_this, p_item );
-    int i_ret = vlclua_scripts_batch_execute( p_this, "meta/fetcher", &fetch_meta, L, NULL );
-    lua_close( L );
+    int i_ret = vlclua_scripts_batch_execute( p_this, "meta/fetcher", &fetch_meta, p_item );
 
     return i_ret;
 }
@@ -235,9 +247,7 @@ int FindArt( vlc_object_t *p_this )
     art_finder_t *p_finder = (art_finder_t *)p_this;
     input_item_t *p_item = p_finder->p_item;
 
-    lua_State *L = init( p_this, p_item );
-    int i_ret = vlclua_scripts_batch_execute( p_this, "meta/art", &fetch_art, L, p_item );
-    lua_close( L );
+    int i_ret = vlclua_scripts_batch_execute( p_this, "meta/art", &fetch_art, p_item );
 
     return i_ret;
 }

modules/misc/lua/vlc.c

@@ -202,8 +202,7 @@ void vlclua_dir_list_free( char **ppsz_dir_list )
  *****************************************************************************/
 int vlclua_scripts_batch_execute( vlc_object_t *p_this,
                                   const char * luadirname,
-                                  int (*func)(vlc_object_t *, const char *, lua_State *, void *),
-                                  lua_State * L,
+                                  int (*func)(vlc_object_t *, const char *, void *),
                                   void * user_data)
 {
     char  *ppsz_dir_list[] = { NULL, NULL, NULL, NULL };
@@ -240,7 +239,7 @@ int vlclua_scripts_batch_execute( vlc_object_t *p_this,
             {
                 msg_Dbg( p_this, "Trying Lua playlist script %s",
                          psz_filename );
-                i_ret = func( p_this, psz_filename, L, user_data );
+                i_ret = func( p_this, psz_filename, user_data );
                 free( psz_filename );
                 if( i_ret == VLC_SUCCESS )
                     break;

modules/misc/lua/vlc.h

@@ -104,8 +104,8 @@ int vlclua_push_ret( lua_State *, int i_error );
  * success.
  *****************************************************************************/
 int vlclua_scripts_batch_execute( vlc_object_t *p_this, const char * luadirname,
-        int (*func)(vlc_object_t *, const char *, lua_State *, void *),
-        lua_State * L, void * user_data );
+        int (*func)(vlc_object_t *, const char *, void *),
+        void * user_data );
 int vlclua_dir_list( vlc_object_t *p_this, const char *luadirname, char **ppsz_dir_list );
 void vlclua_dir_list_free( char **ppsz_dir_list );
 char *vlclua_find_file( vlc_object_t *p_this, const char *psz_luadirname, const char *psz_name );