util/hex.lua
author Kim Alvefur <zash@zash.se>
Sun, 22 Jan 2023 14:45:47 +0100
branch0.12
changeset 12867 891edd1ebde6
parent 12359 a0ff5c438e9d
permissions -rw-r--r--
util.startup: Close state on exit to ensure GC finalizers are called Ensures a last round of garbage collection and that finalizers are called. Fixes things like proper closing of SQLite3 state. There are more calls to os.exit() but most of them exit with an error or in a case where a final GC sweep might not matter as much. It would be nice if this was the default. Calling util.statup.exit() everywhere may be sensible, but would be more involved, requiring imports everywhere.

local s_char = string.char;
local s_format = string.format;
local s_gsub = string.gsub;
local s_lower = string.lower;

local char_to_hex = {};
local hex_to_char = {};

do
	local char, hex;
	for i = 0,255 do
		char, hex = s_char(i), s_format("%02x", i);
		char_to_hex[char] = hex;
		hex_to_char[hex] = char;
	end
end

local function to(s)
	return (s_gsub(s, ".", char_to_hex));
end

local function from(s)
	return (s_gsub(s_lower(s), "%X*(%x%x)%X*", hex_to_char));
end

return {
	encode = to, decode = from;
	-- COMPAT w/pre-0.12:
	to = to, from = from;
};