code.delx.au - offlineimap/blob - src/Network/IMAP/Connection.hs

   1 {- offlineimap component
   2 Copyright (C) 2008 John Goerzen <jgoerzen@complete.org>
   3
   4 This program is free software; you can redistribute it and/or modify
   5 it under the terms of the GNU General Public License as published by
   6 the Free Software Foundation; either version 2 of the License, or
   7 (at your option) any later version.
   8
   9 This program is distributed in the hope that it will be useful,
  10 but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 GNU General Public License for more details.
  13
  14 You should have received a copy of the GNU General Public License
  15 along with this program; if not, write to the Free Software
  16 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  17 -}
  18
  19 module Network.IMAP.Connection where
  20 import Network.IMAP.Types
  21 import Control.Monad.State
  22 import Data.List.Utils(spanList)
  23 import Data.List(genericSplitAt, genericLength)
  24
  25 -- | Take an IMAPString and treat it as messages from the server.
  26 -- | Remember that EOL in IMAP protocols is \r\n!
  27
  28 stringConnection ::
  29     IMAPString ->               -- ^ The initial content of the buffer for the client to read from
  30     IMAPString ->               -- ^ The initial content of the buffer for the client to write to
  31     IMAPConnection (State (IMAPString, IMAPString))
  32 stringConnection sdata wdata =
  33     IMAPConnection {readBytes = lreadBytes,
  34                     readLine = lreadLine,
  35                     writeBytes = lwriteBytes,
  36                     closeConn = return ()}
  37     where
  38           lreadBytes count =
  39               do (s,sw) <- get
  40                  if genericLength s < count
  41                     then fail "EOF in input in readBytes"
  42                     else do let (r, s') = genericSplitAt count s
  43                             put (s', sw)
  44                             return r
  45           lreadLine =
  46               do (s, sw) <- get
  47                  let (line, remainder) = spanList (\x -> "\r\n" /= take 2 x) s
  48                  case remainder of
  49                    [] -> fail "EOF in input in readLine"
  50                    r -> do put (drop 2 r, sw) -- strip of \r\n
  51                            return line
  52
  53           lwriteBytes outdata =
  54               do (s, sw) <- get
  55                  put (s, sw ++ outdata)
  56