## ftplib.rb

# Author: Shugo Maeda <shugo@po.aianet.ne.jp>
# Version: $Revision: 1.7 $

## Code:

require "socket"
require "monitor"

class FTPError < Exception; end
class FTPReplyError < FTPError; end
class FTPTempError < FTPError; end
class FTPPermError < FTPError; end
class FTPProtoError < FTPError; end

class FTP
  
  RCS_ID = %q$Id: ftplib.rb,v 1.7 1998/04/13 12:34:24 shugo Exp shugo $ 
  
  include MonitorMixin
  
  FTP_PORT = 21
  CRLF = "\r\n"
  
  attr_accessor :passive, :return_code, :debug_mode
  attr_reader :welcome, :lastresp
  
  def FTP.open(host, user = nil, passwd = nil, acct = nil)
    new(host, user, passwd, acct)
  end
    
  def initialize(host = nil, user = nil, passwd = nil, acct = nil)
    super
    @passive = false
    @return_code = "\n"
    @debug_mode = false
    if host
      connect(host)
      if user
	login(user, passwd, acct)
      end
    end
  end
  
  def open_socket(host, port)
    if defined? SOCKSsocket and ENV["SOCKS_SERVER"]
      @passive = true
      return SOCKSsocket.open(host, port)
    else
      return TCPsocket.open(host, port)
    end
  end
  private :open_socket
   
  def connect(host, port = FTP_PORT)
    if @debug_mode
      print "connect: ", host, ", ", port, "\n"
    end
    synchronize do
      @sock = open_socket(host, port)
      voidresp
    end
  end
  
  def sanitize(s)
    if s =~ /^PASS /i
      return s[0, 5] + "*" * (s.length - 5)
    else
      return s
    end
  end
  private :sanitize
  
  def putline(line)
    if @debug_mode
      print "put: ", sanitize(line), "\n"
    end
    line = line + CRLF
    @sock.write(line)
  end
  private :putline
   
  def getline
    line = @sock.readline # if get EOF, raise EOFError
    if line[-2, 2] == CRLF
      line = line[0 .. -3]
    elsif line[-1] == ?\r or
	line[-1] == ?\n
      line = line[0 .. -2]
    end
    if @debug_mode
      print "get: ", sanitize(line), "\n"
    end
    return line
  end
  private :getline
  
  def getmultiline
    line = getline
    buff = line
    if line[3] == ?-
      code = line[0, 3]
      begin
	line = getline
	buff << "\n" << line
      end until line[0, 3] == code and line[3] != ?-
    end
    return buff << "\n"
  end
  private :getmultiline
  
  def getresp
    resp = getmultiline
    @lastresp = resp[0, 3]
    c = resp[0]
    case c
    when ?1, ?2, ?3
      return resp
    when ?4
      raise FTPTempError, resp
    when ?5
      raise FTPPermError, resp
    else
      raise FTPProtoError, resp
    end
  end
  private :getresp
  
  def voidresp
    resp = getresp
    if resp[0] != ?2
      raise FTPReplyError, resp
    end
  end
  private :voidresp
  
  def sendcmd(cmd)
    synchronize do
      putline(cmd)
      return getresp
    end
  end
   
  def voidcmd(cmd)
    synchronize do
      putline(cmd)
      voidresp
    end
  end
   
  def sendport(host, port)
    hbytes = host.split(".")
    pbytes = [port / 256, port % 256]
    bytes = hbytes + pbytes
    cmd = "PORT " + bytes.join(",")
    voidcmd(cmd)
  end
  private :sendport
   
  def makeport
    sock = TCPserver.open(0)
    port = sock.addr[1]
    host = TCPsocket.getaddress(@sock.addr[2])
    resp = sendport(host, port)
    return sock
  end
  private :makeport
   
  def transfercmd(cmd)
    if @passive
      host, port = parse227(sendcmd("PASV"))
      conn = open_socket(host, port)
      resp = sendcmd(cmd)
      if resp[0] != ?1
	raise FTPReplyError, resp
      end
    else
      sock = makeport
      resp = sendcmd(cmd)
      if resp[0] != ?1
	raise FTPReplyError, resp
      end
      conn = sock.accept
    end
    return conn
  end
  private :transfercmd
   
  def getaddress
    thishost = Socket.gethostname
    if not thishost.index(".")
      thishost = Socket.gethostbyname(thishost)[0]
    end
    if ENV.has_key?("LOGNAME")
      realuser = ENV["LOGNAME"]
    elsif ENV.has_key?("USER")
      realuser = ENV["USER"]
    else
      realuser = "anonymous"
    end
    return realuser + "@" + thishost
  end
  private :getaddress
   
  def login(user = "anonymous", passwd = nil, acct = nil)
    if user == "anonymous" and passwd == nil
      passwd = getaddress
    end
    
    resp = ""
    synchronize do
      resp = sendcmd('USER ' + user)
      if resp[0] == ?3
	resp = sendcmd('PASS ' + passwd)
      end
      if resp[0] == ?3
	resp = sendcmd('ACCT ' + acct)
      end
    end
    if resp[0] != ?2
      raise FTPReplyError, resp
    end
    @welcome = resp
  end
  
  def retrbinary(cmd, blocksize, callback = Proc.new)
    synchronize do
      voidcmd("TYPE I")
      conn = transfercmd(cmd)
      loop do
	data = conn.read(blocksize)
	break if data == nil
	callback.call(data)
      end
      conn.close
      voidresp
    end
  end
   
  def retrlines(cmd, callback = nil)
    if iterator?
      callback = Proc.new
    elsif not callback.is_a?(Proc)
      callback = Proc.new {|line| print line, "\n"}
    end
    synchronize do
      voidcmd("TYPE A")
      conn = transfercmd(cmd)
      loop do
	line = conn.gets
	break if line == nil
	if line[-2, 2] == CRLF
	  line = line[0 .. -3]
	elsif line[-1] == ?\n
	  line = line[0 .. -2]
	end
	callback.call(line)
      end
      conn.close
      voidresp
    end
  end
  
  def storbinary(cmd, file, blocksize, callback = nil)
    if iterator?
      callback = Proc.new
    end
    use_callback = callback.is_a?(Proc)
    synchronize do
      voidcmd("TYPE I")
      conn = transfercmd(cmd)
      loop do
	buf = file.read(blocksize)
	break if buf == nil
	conn.write(buf)
	callback.call(buf) if use_callback
      end
      conn.close
      voidresp
    end
  end
   
  def storlines(cmd, file, callback = nil)
    if iterator?
      callback = Proc.new
    end
    use_callback = callback.is_a?(Proc)
    synchronize do
      voidcmd("TYPE A")
      conn = transfercmd(cmd)
      loop do
	buf = file.gets
	break if buf == nil
	if buf[-2, 2] != CRLF
	  if buf[-1] == ?\r or
	      buf[-1] == ?\n
	    buf = buf[0 .. -2]
	  end
	  buf = buf + CRLF
	end
	conn.write(buf)
	callback.call(buf) if use_callback
      end
      conn.close
      voidresp
    end
  end
  
  def getbinaryfile(remotefile, localfile, blocksize, callback = nil)
    if iterator?
      callback = Proc.new
    end
    use_callback = callback.is_a?(Proc)
    f = open(localfile, "w")
    begin
      f.binmode
      retrbinary("RETR " + remotefile, blocksize) do |data|
	f.write(data)
	callback.call(data) if use_callback
      end
    ensure
      f.close
    end
  end
   
  def gettextfile(remotefile, localfile, callback = nil)
    if iterator?
      callback = Proc.new
    end
    use_callback = callback.is_a?(Proc)
    f = open(localfile, "w")
    begin
      retrlines("RETR " + remotefile) do |line|
	line = line + @return_code
	f.write(line)
	callback.call(line) if use_callback
      end
    ensure
      f.close
    end
  end
   
  def putbinaryfile(localfile, remotefile, blocksize, callback = nil)
    if iterator?
      callback = Proc.new
    end
    use_callback = callback.is_a?(Proc)
    f = open(localfile)
    begin
      f.binmode
      storbinary("STOR " + remotefile, f, blocksize) do |data|
	callback.call(data) if use_callback
      end
    ensure
      f.close
    end
  end
  
  def puttextfile(localfile, remotefile, callback = nil)
    if iterator?
      callback = Proc.new
    end
    use_callback = callback.is_a?(Proc)
    f = open(localfile)
    begin
      storlines("STOR " + remotefile, f) do |line|
	callback.call(line) if use_callback
      end
    ensure
      f.close
    end
  end
   
  def acct(account)
    cmd = "ACCT " + account
    voidcmd(cmd)
  end
  
  def nlst(dir = nil)
    cmd = "NLST"
    if dir
      cmd = cmd + " " + dir
    end
    files = []
    retrlines(cmd) do |line|
      files.push(line)
    end
    return files
  end
  
  def list(*args, &block)
    cmd = "LIST"
    args.each do |arg|
      cmd = cmd + " " + arg
    end
    if block
      retrlines(cmd, &block)
    else
      lines = []
      retrlines(cmd) do |line|
	lines << line
      end
      return lines
    end
  end
  alias ls list
  alias dir list
  
  def rename(fromname, toname)
    resp = sendcmd("RNFR " + fromname)
    if resp[0] != ?3
      raise FTPReplyError, resp
    end
    voidcmd("RNTO " + toname)
  end
  
  def delete(filename)
    resp = sendcmd("DELE " + filename)
    if resp[0, 3] == "250"
      return
    elsif resp[0] == ?5
      raise FTPPermError, resp
    else
      raise FTPReplyError, resp
    end
  end
  
  def chdir(dirname)
    if dirname == ".."
      begin
	voidcmd("CDUP")
	return
      rescue FTPPermError
	if $![0, 3] != "500"
	  raise FTPPermError, $!
	end
      end
    end
    cmd = "CWD " + dirname
    voidcmd(cmd)
  end
   
  def size(filename)
    voidcmd("TYPE I")
    resp = sendcmd("SIZE " + filename)
    if resp[0, 3] != "213" 
      raise FTPReplyError, resp
    end
    return resp[3..-1].strip 
  end

  MDTM_REGEXP = /^(\d\d\d\d)(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/

  def mtime(filename) 
    str = mdtm(filename)
    ary = str.scan(MDTM_REGEXP)[0].collect {|i| i.to_i} 
    return Time.gm(*ary) 
  end

  def mkdir(dirname)
    resp = sendcmd("MKD " + dirname)
    return parse257(resp)
  end
  
  def rmdir(dirname)
    voidcmd("RMD " + dirname)
  end
  
  def pwd
    resp = sendcmd("PWD")
      return parse257(resp)
  end
  alias getdir pwd
  
  def system
    resp = sendcmd("SYST")
    if resp[0, 3] != "215"
      raise FTPReplyError, resp
    end
    return resp[4 .. -1]
  end
  
  def abort
    line = "ABOR" + CRLF
    print "put: ABOR\n" if @debug_mode
    @sock.send(line, Socket::MSG_OOB)
    resp = getmultiline
    unless ["426", "226", "225"].include?(resp[0, 3])
      raise FTPProtoError, resp
    end
    return resp
  end
   
  def status
    line = "STAT" + CRLF
    print "put: STAT\n" if @debug_mode
    @sock.send(line, Socket::MSG_OOB)
    return getresp
  end
  
  def mdtm(filename)
    resp = sendcmd("MDTM " + filename)
    if resp[0, 3] == "213"
      return resp[3 .. -1].strip
    end
  end
  
  def help(arg = nil)
    cmd = "HELP"
    if arg
      cmd = cmd + " " + arg
    end
    sendcmd(cmd)
  end
  
  def quit
    voidcmd("QUIT")
  end
  
  def close
    @sock.close if @sock and not @sock.closed?
  end
  
  def closed?
    @sock == nil or @sock.closed?
  end
  
  def parse227(resp)
    if resp[0, 3] != "227"
      raise FTPReplyError, resp
    end
    left = resp.index("(")
    right = resp.index(")")
    if left == nil or right == nil
      raise FTPProtoError, resp
    end
    numbers = resp[left + 1 .. right - 1].split(",")
    if numbers.length != 6
      raise FTPProtoError, resp
    end
    host = numbers[0, 4].join(".")
    port = (numbers[4].to_i << 8) + numbers[5].to_i
    return host, port
  end
  private :parse227
  
  def parse257(resp)
    if resp[0, 3] != "257"
      raise FTPReplyError, resp
    end
    if resp[3, 2] != ' "'
      return ""
    end
    dirname = ""
    i = 5
    n = resp.length
    while i < n
      c = resp[i, 1]
      i = i + 1
      if c == '"'
	if i > n or resp[i, 1] != '"'
	  break
	end
	i = i + 1
      end
      dirname = dirname + c
    end
    return dirname
  end
  private :parse257
end

## ftplib.rb ends here