code.delx.au - offlineimap/blob - offlineimap/folder/Maildir.py

   1 # Maildir folder support
   2 # Copyright (C) 2002 - 2007 John Goerzen
   3 # <jgoerzen@complete.org>
   4 #
   5 #    This program is free software; you can redistribute it and/or modify
   6 #    it under the terms of the GNU General Public License as published by
   7 #    the Free Software Foundation; either version 2 of the License, or
   8 #    (at your option) any later version.
   9 #
  10 #    This program is distributed in the hope that it will be useful,
  11 #    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 #    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 #    GNU General Public License for more details.
  14 #
  15 #    You should have received a copy of the GNU General Public License
  16 #    along with this program; if not, write to the Free Software
  17 #    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  18
  19 from Base import BaseFolder
  20 from offlineimap import imaputil
  21 from offlineimap.ui import UIBase
  22 from threading import Lock
  23 import os.path, os, re, time, socket, md5
  24
  25 uidmatchre = re.compile(',U=(\d+)')
  26 flagmatchre = re.compile(':.*2,([A-Z]+)')
  27
  28 timeseq = 0
  29 lasttime = long(0)
  30 timelock = Lock()
  31
  32 def gettimeseq():
  33     global lasttime, timeseq, timelock
  34     timelock.acquire()
  35     try:
  36         thistime = long(time.time())
  37         if thistime == lasttime:
  38             timeseq += 1
  39             return (thistime, timeseq)
  40         else:
  41             lasttime = thistime
  42             timeseq = 0
  43             return (thistime, timeseq)
  44     finally:
  45         timelock.release()
  46
  47 class MaildirFolder(BaseFolder):
  48     def __init__(self, root, name, sep, repository, accountname, config):
  49         self.name = name
  50         self.config = config
  51         self.dofsync = config.getdefaultboolean("general", "fsync", True)
  52         self.root = root
  53         self.sep = sep
  54         self.messagelist = None
  55         self.repository = repository
  56         self.accountname = accountname
  57         BaseFolder.__init__(self)
  58
  59     def getaccountname(self):
  60         return self.accountname
  61
  62     def getfullname(self):
  63         return os.path.join(self.getroot(), self.getname())
  64
  65     def getuidvalidity(self):
  66         """Maildirs have no notion of uidvalidity, so we just return a magic
  67         token."""
  68         return 42
  69
  70     def _scanfolder(self):
  71         """Cache the message list.  Maildir flags are:
  72         R (replied)
  73         S (seen)
  74         T (trashed)
  75         D (draft)
  76         F (flagged)
  77         and must occur in ASCII order."""
  78         retval = {}
  79         files = []
  80         nouidcounter = -1               # Messages without UIDs get
  81                                         # negative UID numbers.
  82         foldermd5 = md5.new(self.getvisiblename()).hexdigest()
  83         folderstr = ',FMD5=' + foldermd5
  84         for dirannex in ['new', 'cur']:
  85             fulldirname = os.path.join(self.getfullname(), dirannex)
  86             files.extend([os.path.join(fulldirname, filename) for
  87                           filename in os.listdir(fulldirname)])
  88         for file in files:
  89             messagename = os.path.basename(file)
  90             foldermatch = messagename.find(folderstr) != -1
  91             if not foldermatch:
  92                 # If there is no folder MD5 specified, or if it mismatches,
  93                 # assume it is a foreign (new) message and generate a
  94                 # negative uid for it
  95                 uid = nouidcounter
  96                 nouidcounter -= 1
  97             else:                       # It comes from our folder.
  98                 uidmatch = uidmatchre.search(messagename)
  99                 uid = None
 100                 if not uidmatch:
 101                     uid = nouidcounter
 102                     nouidcounter -= 1
 103                 else:
 104                     uid = long(uidmatch.group(1))
 105             flagmatch = flagmatchre.search(messagename)
 106             flags = []
 107             if flagmatch:
 108                 flags = [x for x in flagmatch.group(1)]
 109             flags.sort()
 110             retval[uid] = {'uid': uid,
 111                            'flags': flags,
 112                            'filename': file}
 113         return retval
 114
 115     def quickchanged(self, statusfolder):
 116         self.cachemessagelist()
 117         savedmessages = statusfolder.getmessagelist()
 118         if len(self.messagelist) != len(savedmessages):
 119             return True
 120         for uid in self.messagelist.keys():
 121             if uid not in savedmessages:
 122                 return True
 123             if self.messagelist[uid]['flags'] != savedmessages[uid]['flags']:
 124                 return True
 125         return False
 126
 127     def cachemessagelist(self):
 128         if self.messagelist is None:
 129             self.messagelist = self._scanfolder()
 130
 131     def getmessagelist(self):
 132         return self.messagelist
 133
 134     def getmessage(self, uid):
 135         filename = self.messagelist[uid]['filename']
 136         file = open(filename, 'rt')
 137         retval = file.read()
 138         file.close()
 139         return retval.replace("\r\n", "\n")
 140
 141     def getmessagetime( self, uid ):
 142         filename = self.messagelist[uid]['filename']
 143         st = os.stat(filename)
 144         return st.st_mtime
 145
 146     def savemessage(self, uid, content, flags, rtime):
 147         # This function only ever saves to tmp/,
 148         # but it calls savemessageflags() to actually save to cur/ or new/.
 149         ui = UIBase.getglobalui()
 150         ui.debug('maildir', 'savemessage: called to write with flags %s and content %s' % \
 151                  (repr(flags), repr(content)))
 152         if uid < 0:
 153             # We cannot assign a new uid.
 154             return uid
 155         if uid in self.messagelist:
 156             # We already have it.
 157             self.savemessageflags(uid, flags)
 158             return uid
 159
 160         # Otherwise, save the message in tmp/ and then call savemessageflags()
 161         # to give it a permanent home.
 162         tmpdir = os.path.join(self.getfullname(), 'tmp')
 163         messagename = None
 164         attempts = 0
 165         while 1:
 166             if attempts > 15:
 167                 raise IOError, "Couldn't write to file %s" % messagename
 168             timeval, timeseq = gettimeseq()
 169             messagename = '%d_%d.%d.%s,U=%d,FMD5=%s' % \
 170                           (timeval,
 171                            timeseq,
 172                            os.getpid(),
 173                            socket.gethostname(),
 174                            uid,
 175                            md5.new(self.getvisiblename()).hexdigest())
 176             if os.path.exists(os.path.join(tmpdir, messagename)):
 177                 time.sleep(2)
 178                 attempts += 1
 179             else:
 180                 break
 181         tmpmessagename = messagename.split(',')[0]
 182         ui.debug('maildir', 'savemessage: using temporary name %s' % tmpmessagename)
 183         file = open(os.path.join(tmpdir, tmpmessagename), "wt")
 184         file.write(content)
 185
 186         # Make sure the data hits the disk
 187         file.flush()
 188         if self.dofsync:
 189             os.fsync(file.fileno())
 190
 191         file.close()
 192         if rtime != None:
 193             os.utime(os.path.join(tmpdir,tmpmessagename), (rtime,rtime))
 194         ui.debug('maildir', 'savemessage: moving from %s to %s' % \
 195                  (tmpmessagename, messagename))
 196         if tmpmessagename != messagename: # then rename it
 197             os.link(os.path.join(tmpdir, tmpmessagename),
 198                     os.path.join(tmpdir, messagename))
 199             os.unlink(os.path.join(tmpdir, tmpmessagename))
 200
 201         if self.dofsync:
 202             try:
 203                 # fsync the directory (safer semantics in Linux)
 204                 fd = os.open(tmpdir, os.O_RDONLY)
 205                 os.fsync(fd)
 206                 os.close(fd)
 207             except:
 208                 pass
 209
 210         self.messagelist[uid] = {'uid': uid, 'flags': [],
 211                                  'filename': os.path.join(tmpdir, messagename)}
 212         self.savemessageflags(uid, flags)
 213         ui.debug('maildir', 'savemessage: returning uid %d' % uid)
 214         return uid
 215
 216     def getmessageflags(self, uid):
 217         return self.messagelist[uid]['flags']
 218
 219     def savemessageflags(self, uid, flags):
 220         oldfilename = self.messagelist[uid]['filename']
 221         newpath, newname = os.path.split(oldfilename)
 222         tmpdir = os.path.join(self.getfullname(), 'tmp')
 223         if 'S' in flags:
 224             # If a message has been seen, it goes into the cur
 225             # directory.  CR debian#152482, [complete.org #4]
 226             newpath = os.path.join(self.getfullname(), 'cur')
 227         else:
 228             newpath = os.path.join(self.getfullname(), 'new')
 229         infostr = ':'
 230         infomatch = re.search('(:.*)$', newname)
 231         if infomatch:                   # If the info string is present..
 232             infostr = infomatch.group(1)
 233             newname = newname.split(':')[0] # Strip off the info string.
 234         infostr = re.sub('2,[A-Z]*', '', infostr)
 235         flags.sort()
 236         infostr += '2,' + ''.join(flags)
 237         newname += infostr
 238
 239         newfilename = os.path.join(newpath, newname)
 240         if (newfilename != oldfilename):
 241             os.rename(oldfilename, newfilename)
 242             self.messagelist[uid]['flags'] = flags
 243             self.messagelist[uid]['filename'] = newfilename
 244
 245         # By now, the message had better not be in tmp/ land!
 246         final_dir, final_name = os.path.split(self.messagelist[uid]['filename'])
 247         assert final_dir != tmpdir
 248
 249     def deletemessage(self, uid):
 250         if not uid in self.messagelist:
 251             return
 252         filename = self.messagelist[uid]['filename']
 253         try:
 254             os.unlink(filename)
 255         except OSError:
 256             # Can't find the file -- maybe already deleted?
 257             newmsglist = self._scanfolder()
 258             if uid in newmsglist:       # Nope, try new filename.
 259                 os.unlink(newmsglist[uid]['filename'])
 260             # Yep -- return.
 261         del(self.messagelist[uid])
 262