Setup lua module search path

For example, if runing script <user dir>/lua/intf/script.lua, the following paths will be added:
  <user dir>/lua/modules/?.lua
  <user dir>/lua/intf/modules/?.lua
  <share dir>/lua/modules/?.lua
  <share dir>/lua/intf/modules/?.lua

If runing script <share dir>/lua/intf/script.lua, the following paths will be added:
  <share dir>/lua/modules/?.lua
  <share dir>/lua/intf/modules/?.lua

modules/misc/lua/demux.c

@@ -147,6 +147,14 @@ static int probe_luascript( vlc_object_t *p_this, const char * psz_filename,
 
     lua_pop( L, 1 );
 
+    /* Setup the module search path */
+    if( vlclua_add_modules_path( p_demux, L, psz_filename ) )
+    {
+        msg_Warn( p_demux, "Error while setting the module search path for %s",
+                  psz_filename );
+        goto error;
+    }
+
     /* Load and run the script(s) */
     if( luaL_dofile( L, psz_filename ) )
     {
@@ -197,7 +205,6 @@ error:
 int Import_LuaPlaylist( vlc_object_t *p_this )
 {
     demux_t *p_demux = (demux_t *)p_this;
-    lua_State *L;
     int ret;
 
     p_demux->p_sys = (demux_sys_t*)malloc( sizeof( demux_sys_t ) );

modules/misc/lua/extension.c

@@ -742,6 +742,13 @@ static lua_State* GetLuaState( extensions_manager_t *p_mgr,
             lua_pushcfunction( L, vlclua_extension_deactivate );
             lua_setfield( L, -2, "deactivate" );
 
+            /* Setup the module search path */
+            if( vlclua_add_modules_path( p_mgr, L, p_ext->psz_name ) )
+            {
+                msg_Warn( p_mgr, "Error while setting the module search path for %s", p_ext->psz_name );
+                return NULL;
+            }
+
             /* Load and run the script(s) */
             if( luaL_dofile( L, p_ext->psz_name ) != 0 )
             {

modules/misc/lua/intf.c

@@ -201,28 +201,13 @@ int Open_LuaIntf( vlc_object_t *p_this )
     /* clean up */
     lua_pop( L, 1 );
 
-    /* <gruik> */
     /* Setup the module search path */
+    if( vlclua_add_modules_path( p_intf, L, p_sys->psz_filename ) )
     {
-    char *psz_command;
-    char *psz_char = strrchr(p_sys->psz_filename,DIR_SEP_CHAR);
-    *psz_char = '\0';
-    /* FIXME: don't use luaL_dostring */
-    if( asprintf( &psz_command,
-                  "package.path = [[%s"DIR_SEP"modules"DIR_SEP"?.lua;]]..package.path",
-                  p_sys->psz_filename ) < 0 )
-    {
+        msg_Warn( p_intf, "Error while setting the module search path for %s",
+                  p_sys->psz_filename );
         goto error;
     }
-    *psz_char = DIR_SEP_CHAR;
-    if( luaL_dostring( L, psz_command ) )
-    {
-        free( psz_command );
-        goto error;
-    }
-    free( psz_command );
-    }
-    /* </gruik> */
 
     psz_config = var_CreateGetString( p_intf, "lua-config" );
     if( psz_config && *psz_config )

modules/misc/lua/meta.c

@@ -51,7 +51,7 @@
  *****************************************************************************/
 static const luaL_Reg p_reg[] = { { NULL, NULL } };
 
-static lua_State * init( vlc_object_t *p_this, input_item_t * p_item )
+static lua_State * init( vlc_object_t *p_this, input_item_t * p_item, const char *psz_filename )
 {
     lua_State * L = luaL_newstate();
     if( !L )
@@ -76,6 +76,14 @@ static lua_State * init( vlc_object_t *p_this, input_item_t * p_item )
     lua_pushlightuserdata( L, p_this );
     lua_setfield( L, -2, "private" );
 
+    if( vlclua_add_modules_path( p_this, L, psz_filename ) )
+    {
+        msg_Warn( p_this, "Error while setting the module search path for %s",
+                  psz_filename );
+        lua_close( L );
+        return NULL;
+    }
+
     return L;
 }
 
@@ -131,7 +139,9 @@ static int fetch_art( vlc_object_t *p_this, const char * psz_filename,
     input_item_t * p_item = user_data;
     int s;
 
-    lua_State *L = init( p_this, p_item );
+    lua_State *L = init( p_this, p_item, psz_filename );
+    if( !L )
+        return VLC_EGENERIC;
 
     int i_ret = run(p_this, psz_filename, L, "fetch_art");
     if(i_ret != VLC_SUCCESS)
@@ -178,7 +188,9 @@ static int read_meta( vlc_object_t *p_this, const char * psz_filename,
                       void * user_data )
 {
     input_item_t * p_item = user_data;
-    lua_State *L = init( p_this, p_item );
+    lua_State *L = init( p_this, p_item, psz_filename );
+    if( !L )
+        return VLC_EGENERIC;
 
     int i_ret = run(p_this, psz_filename, L, "read_meta");
     if(i_ret != VLC_SUCCESS)
@@ -201,7 +213,9 @@ static int fetch_meta( vlc_object_t *p_this, const char * psz_filename,
                        void * user_data )
 {
     input_item_t * p_item = user_data;
-    lua_State *L = init( p_this, p_item );
+    lua_State *L = init( p_this, p_item, psz_filename );
+    if( !L )
+        return VLC_EGENERIC;
 
     int ret = run(p_this, psz_filename, L, "fetch_meta");
     lua_close( L );

modules/misc/lua/vlc.c

@@ -660,3 +660,100 @@ error:
     vlclua_dir_list_free( ppsz_dir_list );
     return VLC_ENOMEM;
 }
+
+static int vlclua_add_modules_path_inner( lua_State *L, const char *psz_path )
+{
+    /* FIXME: don't use luaL_dostring */
+    char *psz_command = NULL;
+    if( asprintf( &psz_command,
+                  "package.path =[[%s"DIR_SEP"modules"DIR_SEP"?.lua;]]..package.path",
+                  psz_path ) < 0 )
+    {
+        return 1;
+    }
+
+    if( luaL_dostring( L, psz_command ) )
+    {
+        free( psz_command );
+        return 1;
+    }
+    free( psz_command );
+
+    return 0;
+}
+
+int __vlclua_add_modules_path( vlc_object_t *obj, lua_State *L, const char *psz_filename )
+{
+    /* Setup the module search path:
+     *   * "The script's directory"/modules
+     *   * "The script's parent directory"/modules
+     *   * and so on for all the next directories in the directory list
+     */
+
+    char *psz_path = strdup( psz_filename );
+    if( !psz_path )
+        return 1;
+
+    char *psz_char = strrchr( psz_path, DIR_SEP_CHAR );
+    if( !psz_char )
+    {
+        free( psz_path );
+        return 1;
+    }
+    *psz_char = '\0';
+
+    /* psz_path now holds the file's directory */
+    psz_char = strrchr( psz_path, DIR_SEP_CHAR );
+    if( !psz_char )
+    {
+        free( psz_path );
+        return 1;
+    }
+    *psz_char = '\0';
+
+    /* psz_path now holds the file's parent directory */
+    if( vlclua_add_modules_path_inner( L, psz_path ) )
+    {
+        free( psz_path );
+        return 1;
+    }
+    *psz_char = DIR_SEP_CHAR;
+
+    /* psz_path now holds the file's directory */
+    if( vlclua_add_modules_path_inner( L, psz_path ) )
+    {
+        free( psz_path );
+        return 1;
+    }
+
+    char  *ppsz_dir_list[] = { NULL, NULL, NULL, NULL };
+    vlclua_dir_list( obj, psz_char+1/* gruik? */, ppsz_dir_list );
+    char **ppsz_dir = ppsz_dir_list;
+
+    for( ; *ppsz_dir && strcmp( *ppsz_dir, psz_path ); ppsz_dir++ );
+    free( psz_path );
+
+    for( ; *ppsz_dir; ppsz_dir++ )
+    {
+        psz_path = *ppsz_dir;
+        psz_char = strrchr( psz_path, DIR_SEP_CHAR );
+        if( !psz_char )
+            goto exit;
+
+        *psz_char = '\0';
+        if( vlclua_add_modules_path_inner( L, psz_path ) )
+            goto exit;
+        *psz_char = DIR_SEP_CHAR;
+
+        if( vlclua_add_modules_path_inner( L, psz_path ) )
+            goto exit;
+    }
+
+    vlclua_dir_list_free( ppsz_dir_list );
+    return 0;
+
+    exit:
+    vlclua_dir_list_free( ppsz_dir_list );
+    return 1;
+}
+

modules/misc/lua/vlc.h

@@ -124,6 +124,9 @@ int __vlclua_playlist_add_internal( vlc_object_t *, lua_State *, playlist_t *,
                                     input_item_t *, bool );
 #define vlclua_playlist_add_internal(a,b,c,d,e) __vlclua_playlist_add_internal(VLC_OBJECT(a),b,c,d,e)
 
+int __vlclua_add_modules_path( vlc_object_t *, lua_State *, const char *psz_filename );
+#define vlclua_add_modules_path( a, b, c ) __vlclua_add_modules_path(VLC_OBJECT(a), b, c)
+
 /**
  * Per-interface private state
  */