88 lines
2.4 KiB
Lua
88 lines
2.4 KiB
Lua
-----------------------------------------------------------------------------
|
|
-- MIME support for the Lua language.
|
|
-- Author: Diego Nehab
|
|
-- Conforming to RFCs 2045-2049
|
|
-- RCS ID: $Id: mime.lua,v 1.29 2007/06/11 23:44:54 diego Exp $
|
|
-----------------------------------------------------------------------------
|
|
|
|
-----------------------------------------------------------------------------
|
|
-- Declare module and import dependencies
|
|
-----------------------------------------------------------------------------
|
|
local base = _G
|
|
local ltn12 = require("ltn12")
|
|
local mime = require("mime.core")
|
|
local io = require("io")
|
|
local string = require("string")
|
|
module("mime")
|
|
|
|
-- encode, decode and wrap algorithm tables
|
|
encodet = {}
|
|
decodet = {}
|
|
wrapt = {}
|
|
|
|
-- creates a function that chooses a filter by name from a given table
|
|
local function choose(table)
|
|
return function(name, opt1, opt2)
|
|
if base.type(name) ~= "string" then
|
|
name, opt1, opt2 = "default", name, opt1
|
|
end
|
|
local f = table[name or "nil"]
|
|
if not f then
|
|
base.error("unknown key (" .. base.tostring(name) .. ")", 3)
|
|
else return f(opt1, opt2) end
|
|
end
|
|
end
|
|
|
|
-- define the encoding filters
|
|
encodet['base64'] = function()
|
|
return ltn12.filter.cycle(b64, "")
|
|
end
|
|
|
|
encodet['quoted-printable'] = function(mode)
|
|
return ltn12.filter.cycle(qp, "",
|
|
(mode == "binary") and "=0D=0A" or "\r\n")
|
|
end
|
|
|
|
-- define the decoding filters
|
|
decodet['base64'] = function()
|
|
return ltn12.filter.cycle(unb64, "")
|
|
end
|
|
|
|
decodet['quoted-printable'] = function()
|
|
return ltn12.filter.cycle(unqp, "")
|
|
end
|
|
|
|
local function format(chunk)
|
|
if chunk then
|
|
if chunk == "" then return "''"
|
|
else return string.len(chunk) end
|
|
else return "nil" end
|
|
end
|
|
|
|
-- define the line-wrap filters
|
|
wrapt['text'] = function(length)
|
|
length = length or 76
|
|
return ltn12.filter.cycle(wrp, length, length)
|
|
end
|
|
wrapt['base64'] = wrapt['text']
|
|
wrapt['default'] = wrapt['text']
|
|
|
|
wrapt['quoted-printable'] = function()
|
|
return ltn12.filter.cycle(qpwrp, 76, 76)
|
|
end
|
|
|
|
-- function that choose the encoding, decoding or wrap algorithm
|
|
encode = choose(encodet)
|
|
decode = choose(decodet)
|
|
wrap = choose(wrapt)
|
|
|
|
-- define the end-of-line normalization filter
|
|
function normalize(marker)
|
|
return ltn12.filter.cycle(eol, 0, marker)
|
|
end
|
|
|
|
-- high level stuffing filter
|
|
function stuff()
|
|
return ltn12.filter.cycle(dot, 2)
|
|
end
|