File

util/envload.lua @ 10571:cfeb0077c9e9

net.server_epoll: Avoid concatenating buffer with single item Saves creating a string that'll be identical to buffer[1] anyways, as well as a C function call. Depending on Lua version and length of the string, this could be reusing an interned string, but a longer one would probably be duplicated for no reason. Having exactly one item in the buffer seems like it would be fairly common, but I have not done an extensive study. If opportunistic writes are enabled then it will be even more likely. This special case could be optimized like this in table.concat but it does not look like it is.
author Kim Alvefur <zash@zash.se>
date Sat, 28 Dec 2019 06:18:58 +0100
parent 8416:bc9cb23b604a
child 12576:d1aacc6a81ac
line wrap: on
line source

-- Prosody IM
-- Copyright (C) 2008-2011 Florian Zeitz
--
-- This project is MIT/X11 licensed. Please see the
-- COPYING file in the source package for more information.
--
-- luacheck: ignore 113/setfenv 113/loadstring

local load, loadstring, setfenv = load, loadstring, setfenv;
local io_open = io.open;
local envload;
local envloadfile;

if setfenv then
	function envload(code, source, env)
		local f, err = loadstring(code, source);
		if f and env then setfenv(f, env); end
		return f, err;
	end

	function envloadfile(file, env)
		local fh, err, errno = io_open(file);
		if not fh then return fh, err, errno; end
		local f, err = load(function () return fh:read(2048); end, "@"..file);
		fh:close();
		if f and env then setfenv(f, env); end
		return f, err;
	end
else
	function envload(code, source, env)
		return load(code, source, nil, env);
	end

	function envloadfile(file, env)
		local fh, err, errno = io_open(file);
		if not fh then return fh, err, errno; end
		local f, err = load(fh:lines(2048), "@"..file, nil, env);
		fh:close();
		return f, err;
	end
end

return { envload = envload, envloadfile = envloadfile };