--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/smtp.lua	Tue Aug 26 18:40:01 2008 -0700
@@ -0,0 +1,251 @@
+-----------------------------------------------------------------------------
+-- SMTP client support for the Lua language.
+-- LuaSocket toolkit.
+-- Author: Diego Nehab
+-- RCS ID: $Id: smtp.lua,v 1.46 2007/03/12 04:08:40 diego Exp $
+-----------------------------------------------------------------------------
+
+-----------------------------------------------------------------------------
+-- Declare module and import dependencies
+-----------------------------------------------------------------------------
+local base = _G
+local coroutine = require("coroutine")
+local string = require("string")
+local math = require("math")
+local os = require("os")
+local socket = require("socket")
+local tp = require("socket.tp")
+local ltn12 = require("ltn12")
+local mime = require("mime")
+module("socket.smtp")
+
+-----------------------------------------------------------------------------
+-- Program constants
+-----------------------------------------------------------------------------
+-- timeout for connection
+TIMEOUT = 60
+-- default server used to send e-mails
+SERVER = "localhost"
+-- default port
+PORT = 25
+-- domain used in HELO command and default sendmail
+-- If we are under a CGI, try to get from environment
+DOMAIN = os.getenv("SERVER_NAME") or "localhost"
+-- default time zone (means we don't know)
+ZONE = "-0000"
+
+---------------------------------------------------------------------------
+-- Low level SMTP API
+-----------------------------------------------------------------------------
+local metat = { __index = {} }
+
+function metat.__index:greet(domain)
+    self.try(self.tp:check("2.."))
+    self.try(self.tp:command("EHLO", domain or DOMAIN))
+    return socket.skip(1, self.try(self.tp:check("2..")))
+end
+
+function metat.__index:mail(from)
+    self.try(self.tp:command("MAIL", "FROM:" .. from))
+    return self.try(self.tp:check("2.."))
+end
+
+function metat.__index:rcpt(to)
+    self.try(self.tp:command("RCPT", "TO:" .. to))
+    return self.try(self.tp:check("2.."))
+end
+
+function metat.__index:data(src, step)
+    self.try(self.tp:command("DATA"))
+    self.try(self.tp:check("3.."))
+    self.try(self.tp:source(src, step))
+    self.try(self.tp:send("\r\n.\r\n"))
+    return self.try(self.tp:check("2.."))
+end
+
+function metat.__index:quit()
+    self.try(self.tp:command("QUIT"))
+    return self.try(self.tp:check("2.."))
+end
+
+function metat.__index:close()
+    return self.tp:close()
+end
+
+function metat.__index:login(user, password)
+    self.try(self.tp:command("AUTH", "LOGIN"))
+    self.try(self.tp:check("3.."))
+    self.try(self.tp:command(mime.b64(user)))
+    self.try(self.tp:check("3.."))
+    self.try(self.tp:command(mime.b64(password)))
+    return self.try(self.tp:check("2.."))
+end
+
+function metat.__index:plain(user, password)
+    local auth = "PLAIN " .. mime.b64("\0" .. user .. "\0" .. password)
+    self.try(self.tp:command("AUTH", auth))
+    return self.try(self.tp:check("2.."))
+end
+
+function metat.__index:auth(user, password, ext)
+    if not user or not password then return 1 end
+    if string.find(ext, "AUTH[^\n]+LOGIN") then
+        return self:login(user, password)
+    elseif string.find(ext, "AUTH[^\n]+PLAIN") then
+        return self:plain(user, password)
+    else
+        self.try(nil, "authentication not supported")
+    end
+end
+
+-- send message or throw an exception
+function metat.__index:send(mailt)
+    self:mail(mailt.from)
+    if base.type(mailt.rcpt) == "table" then
+        for i,v in base.ipairs(mailt.rcpt) do
+            self:rcpt(v)
+        end
+    else
+        self:rcpt(mailt.rcpt)
+    end
+    self:data(ltn12.source.chain(mailt.source, mime.stuff()), mailt.step)
+end
+
+function open(server, port, create)
+    local tp = socket.try(tp.connect(server or SERVER, port or PORT,
+        TIMEOUT, create))
+    local s = base.setmetatable({tp = tp}, metat)
+    -- make sure tp is closed if we get an exception
+    s.try = socket.newtry(function()
+        s:close()
+    end)
+    return s
+end
+
+-- convert headers to lowercase
+local function lower_headers(headers)
+    local lower = {}
+    for i,v in base.pairs(headers or lower) do
+        lower[string.lower(i)] = v
+    end
+    return lower
+end
+
+---------------------------------------------------------------------------
+-- Multipart message source
+-----------------------------------------------------------------------------
+-- returns a hopefully unique mime boundary
+local seqno = 0
+local function newboundary()
+    seqno = seqno + 1
+    return string.format('%s%05d==%05u', os.date('%d%m%Y%H%M%S'),
+        math.random(0, 99999), seqno)
+end
+
+-- send_message forward declaration
+local send_message
+
+-- yield the headers all at once, it's faster
+local function send_headers(headers)
+    local h = "\r\n"
+    for i,v in base.pairs(headers) do
+        h = i .. ': ' .. v .. "\r\n" .. h
+    end
+    coroutine.yield(h)
+end
+
+-- yield multipart message body from a multipart message table
+local function send_multipart(mesgt)
+    -- make sure we have our boundary and send headers
+    local bd = newboundary()
+    local headers = lower_headers(mesgt.headers or {})
+    headers['content-type'] = headers['content-type'] or 'multipart/mixed'
+    headers['content-type'] = headers['content-type'] ..
+        '; boundary="' ..  bd .. '"'
+    send_headers(headers)
+    -- send preamble
+    if mesgt.body.preamble then
+        coroutine.yield(mesgt.body.preamble)
+        coroutine.yield("\r\n")
+    end
+    -- send each part separated by a boundary
+    for i, m in base.ipairs(mesgt.body) do
+        coroutine.yield("\r\n--" .. bd .. "\r\n")
+        send_message(m)
+    end
+    -- send last boundary
+    coroutine.yield("\r\n--" .. bd .. "--\r\n\r\n")
+    -- send epilogue
+    if mesgt.body.epilogue then
+        coroutine.yield(mesgt.body.epilogue)
+        coroutine.yield("\r\n")
+    end
+end
+
+-- yield message body from a source
+local function send_source(mesgt)
+    -- make sure we have a content-type
+    local headers = lower_headers(mesgt.headers or {})
+    headers['content-type'] = headers['content-type'] or
+        'text/plain; charset="iso-8859-1"'
+    send_headers(headers)
+    -- send body from source
+    while true do
+        local chunk, err = mesgt.body()
+        if err then coroutine.yield(nil, err)
+        elseif chunk then coroutine.yield(chunk)
+        else break end
+    end
+end
+
+-- yield message body from a string
+local function send_string(mesgt)
+    -- make sure we have a content-type
+    local headers = lower_headers(mesgt.headers or {})
+    headers['content-type'] = headers['content-type'] or
+        'text/plain; charset="iso-8859-1"'
+    send_headers(headers)
+    -- send body from string
+    coroutine.yield(mesgt.body)
+end
+
+-- message source
+function send_message(mesgt)
+    if base.type(mesgt.body) == "table" then send_multipart(mesgt)
+    elseif base.type(mesgt.body) == "function" then send_source(mesgt)
+    else send_string(mesgt) end
+end
+
+-- set defaul headers
+local function adjust_headers(mesgt)
+    local lower = lower_headers(mesgt.headers)
+    lower["date"] = lower["date"] or
+        os.date("!%a, %d %b %Y %H:%M:%S ") .. (mesgt.zone or ZONE)
+    lower["x-mailer"] = lower["x-mailer"] or socket._VERSION
+    -- this can't be overriden
+    lower["mime-version"] = "1.0"
+    return lower
+end
+
+function message(mesgt)
+    mesgt.headers = adjust_headers(mesgt)
+    -- create and return message source
+    local co = coroutine.create(function() send_message(mesgt) end)
+    return function()
+        local ret, a, b = coroutine.resume(co)
+        if ret then return a, b
+        else return nil, a end
+    end
+end
+
+---------------------------------------------------------------------------
+-- High level SMTP API
+-----------------------------------------------------------------------------
+send = socket.protect(function(mailt)
+    local s = open(mailt.server, mailt.port, mailt.create)
+    local ext = s:greet(mailt.domain)
+    s:auth(mailt.user, mailt.password, ext)
+    s:send(mailt)
+    s:quit()
+    return s:close()
+end)