lua optimize current_path function

frees up around 500 bytes by using the builtin string functionality

Change-Id: Icd4ec921d3fec339b8a4b7f80c9c63d51d4c101c

apps/plugins/lua/loadlib.c

@@ -54,7 +54,10 @@ static const char *pushnexttemplate (lua_State *L, const char *path) {
 
 static const char *findfile (lua_State *L, const char *name,
                                            const char *pname) {
-  const char *path, *current_path = get_current_path(L, 2);
+  get_current_path(L, 2);
+  const char *current_path = lua_tostring(L, -1);
+  const char *path;
+
   name = luaL_gsub(L, name, ".", LUA_DIRSEP);
   lua_getfield(L, LUA_ENVIRONINDEX, pname);
   path = lua_tostring(L, -1);

apps/plugins/lua/rockaux.c

@@ -73,9 +73,8 @@ int strcoll(const char * str1, const char * str2)
     return rb->strcmp(str1, str2);
 }
 
-const char* get_current_path(lua_State *L, int level)
+int get_current_path(lua_State *L, int level)
 {
-    static char buffer[MAX_PATH];
     lua_Debug ar;
 
     if(lua_getstack(L, level, &ar))
@@ -84,22 +83,15 @@ const char* get_current_path(lua_State *L, int level)
             and write it to dest. */
         lua_getinfo(L, "S", &ar);
 
-        char* curfile = (char*) &ar.source[1];
-        char* pos = rb->strrchr(curfile, '/');
+        const char* curfile = &ar.source[1];
+        const char* pos = rb->strrchr(curfile, '/');
         if(pos != NULL)
         {
-            unsigned int len = (unsigned int)(pos - curfile);
-            len = len + 1 > sizeof(buffer) ? sizeof(buffer) - 1 : len;
-
-            if(len > 0)
-                memcpy(buffer, curfile, len);
-
-            buffer[len] = '/';
-            buffer[len+1] = '\0';
-
-            return buffer;
+            lua_pushlstring (L, curfile, pos - curfile + 1);
+            return 1;
         }
     }
 
-    return NULL;
+    lua_pushnil(L);    
+    return 1;
 }

apps/plugins/lua/rocklib.c

@@ -194,13 +194,7 @@ RB_WRAP(font_getstringsize)
 
 RB_WRAP(current_path)
 {
-    const char *current_path = get_current_path(L, 1);
-    if(current_path != NULL)
-        lua_pushstring(L, current_path);
-    else
-        lua_pushnil(L);
-
-    return 1;
+    return get_current_path(L, 1);
 }
 
 static void fill_text_message(lua_State *L, struct text_message * message,

apps/plugins/lua/rocklib.h

@@ -46,7 +46,7 @@ struct lua_str_reg {
 };
 
 LUALIB_API int (luaopen_rock) (lua_State *L);
-const char* get_current_path(lua_State *L, int level);
+int get_current_path(lua_State *L, int level);
 
 #endif /* _ROCKLIB_H_ */