Function lua_callvalue

src/lua.cc:344–396

* @brief Call a lua function to get a single value. */

 * @brief Call a lua function to get a single value.
 */
gchar *lua_callvalue(FileData *fd, const gchar *file, const gchar *function)
{
	g_autofree gchar *path = g_build_filename(get_rc_dir(), "lua", file, NULL);
	if (access(path, R_OK) == -1)
		{
		g_free(path);
		path = g_build_filename(gq_bindir, file, NULL);
		if (access(path, R_OK) == -1)
			{
			return g_strdup("");
			}
		}

	/* Collection Table (Dummy at the moment) */
	lua_newtable(L);
	lua_setglobal(L, "Collection");

	/* Current Image */
	auto image_data = static_cast<FileData **>(lua_newuserdata(L, sizeof(FileData *)));
	luaL_getmetatable(L, "Image");
	lua_setmetatable(L, -2);
	lua_setglobal(L, "Image");

	*image_data = fd;

	gint result;
	if (file[0] == '\0')
		{
		result = luaL_dostring(L, function);
		}
	else
		{
		result = luaL_dofile(L, path);
		}

	if (result)
		{
		return g_strdup_printf("Error running lua script: %s", lua_tostring(L, -1));
		}

	gchar *data = g_strdup(lua_tostring(L, -1));
	g_autoptr(GError) error = nullptr;
	g_autofree gchar *tmp = g_locale_to_utf8(data, strlen(data), nullptr, nullptr, &error);
	if (error)
		{
		log_printf("Error converting lua output from locale to UTF-8: %s\n", error->message);
		}
	else
		{
		std::swap(data, tmp);
		}
	return data;
}

/* vim: set shiftwidth=8 softtabstop=0 cindent cinoptions={1s: */