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):
  49         self.name = name
  50         self.root = root
  51         self.sep = sep
  52         self.messagelist = None
  53         self.repository = repository
  54         self.accountname = accountname
  55         BaseFolder.__init__(self)
  56
  57     def getaccountname(self):
  58         return self.accountname
  59
  60     def getfullname(self):
  61         return os.path.join(self.getroot(), self.getname())
  62
  63     def getuidvalidity(self):
  64         """Maildirs have no notion of uidvalidity, so we just return a magic
  65         token."""
  66         return 42
  67
  68     def _scanfolder(self):
  69         """Cache the message list.  Maildir flags are:
  70         R (replied)
  71         S (seen)
  72         T (trashed)
  73         D (draft)
  74         F (flagged)
  75         and must occur in ASCII order."""
  76         retval = {}
  77         files = []
  78         nouidcounter = -1               # Messages without UIDs get
  79                                         # negative UID numbers.
  80         foldermd5 = md5.new(self.getvisiblename()).hexdigest()
  81         folderstr = ',FMD5=' + foldermd5
  82         for dirannex in ['new', 'cur']:
  83             fulldirname = os.path.join(self.getfullname(), dirannex)
  84             files.extend([os.path.join(fulldirname, filename) for
  85                           filename in os.listdir(fulldirname)])
  86         for file in files:
  87             messagename = os.path.basename(file)
  88             foldermatch = messagename.find(folderstr) != -1
  89             if not foldermatch:
  90                 # If there is no folder MD5 specified, or if it mismatches,
  91                 # assume it is a foreign (new) message and generate a
  92                 # negative uid for it
  93                 uid = nouidcounter
  94                 nouidcounter -= 1
  95             else:                       # It comes from our folder.
  96                 uidmatch = uidmatchre.search(messagename)
  97                 uid = None
  98                 if not uidmatch:
  99                     uid = nouidcounter
 100                     nouidcounter -= 1
 101                 else:
 102                     uid = long(uidmatch.group(1))
 103             flagmatch = flagmatchre.search(messagename)
 104             flags = []
 105             if flagmatch:
 106                 flags = [x for x in flagmatch.group(1)]
 107             flags.sort()
 108             retval[uid] = {'uid': uid,
 109                            'flags': flags,
 110                            'filename': file}
 111         return retval
 112
 113     def quickchanged(self, statusfolder):
 114         self.cachemessagelist()
 115         savedmessages = statusfolder.getmessagelist()
 116         if len(self.messagelist) != len(savedmessages):
 117             return True
 118         for uid in self.messagelist.keys():
 119             if uid not in savedmessages:
 120                 return True
 121             if self.messagelist[uid]['flags'] != savedmessages[uid]['flags']:
 122                 return True
 123         return False
 124
 125     def cachemessagelist(self):
 126         if self.messagelist is None:
 127             self.messagelist = self._scanfolder()
 128
 129     def getmessagelist(self):
 130         return self.messagelist
 131
 132     def getmessage(self, uid):
 133         filename = self.messagelist[uid]['filename']
 134         file = open(filename, 'rt')
 135         retval = file.read()
 136         file.close()
 137         return retval.replace("\r\n", "\n")
 138
 139     def getmessagetime( self, uid ):
 140         filename = self.messagelist[uid]['filename']
 141         st = os.stat(filename)
 142         return st.st_mtime
 143
 144     def savemessage(self, uid, content, flags, rtime):
 145         # This function only ever saves to tmp/,
 146         # but it calls savemessageflags() to actually save to cur/ or new/.
 147         ui = UIBase.getglobalui()
 148         ui.debug('maildir', 'savemessage: called to write with flags %s and content %s' % \
 149                  (repr(flags), repr(content)))
 150         if uid < 0:
 151             # We cannot assign a new uid.
 152             return uid
 153         if uid in self.messagelist:
 154             # We already have it.
 155             self.savemessageflags(uid, flags)
 156             return uid
 157
 158         # Otherwise, save the message in tmp/ and then call savemessageflags()
 159         # to give it a permanent home.
 160         tmpdir = os.path.join(self.getfullname(), 'tmp')
 161         messagename = None
 162         attempts = 0
 163         while 1:
 164             if attempts > 15:
 165                 raise IOError, "Couldn't write to file %s" % messagename
 166             timeval, timeseq = gettimeseq()
 167             messagename = '%d_%d.%d.%s,U=%d,FMD5=%s' % \
 168                           (timeval,
 169                            timeseq,
 170                            os.getpid(),
 171                            socket.gethostname(),
 172                            uid,
 173                            md5.new(self.getvisiblename()).hexdigest())
 174             if os.path.exists(os.path.join(tmpdir, messagename)):
 175                 time.sleep(2)
 176                 attempts += 1
 177             else:
 178                 break
 179         tmpmessagename = messagename.split(',')[0]
 180         ui.debug('maildir', 'savemessage: using temporary name %s' % tmpmessagename)
 181         file = open(os.path.join(tmpdir, tmpmessagename), "wt")
 182         file.write(content)
 183
 184         # Make sure the data hits the disk
 185         file.flush()
 186         os.fsync(file.fileno())
 187
 188         file.close()
 189         if rtime != None:
 190             os.utime(os.path.join(tmpdir,tmpmessagename), (rtime,rtime))
 191         ui.debug('maildir', 'savemessage: moving from %s to %s' % \
 192                  (tmpmessagename, messagename))
 193         if tmpmessagename != messagename: # then rename it
 194             os.link(os.path.join(tmpdir, tmpmessagename),
 195                     os.path.join(tmpdir, messagename))
 196             os.unlink(os.path.join(tmpdir, tmpmessagename))
 197
 198         try:
 199             # fsync the directory (safer semantics in Linux)
 200             fd = os.open(tmpdir, os.O_RDONLY)
 201             os.fsync(fd)
 202             os.close(fd)
 203         except:
 204             pass
 205
 206         self.messagelist[uid] = {'uid': uid, 'flags': [],
 207                                  'filename': os.path.join(tmpdir, messagename)}
 208         self.savemessageflags(uid, flags)
 209         ui.debug('maildir', 'savemessage: returning uid %d' % uid)
 210         return uid
 211
 212     def getmessageflags(self, uid):
 213         return self.messagelist[uid]['flags']
 214
 215     def savemessageflags(self, uid, flags):
 216         oldfilename = self.messagelist[uid]['filename']
 217         newpath, newname = os.path.split(oldfilename)
 218         tmpdir = os.path.join(self.getfullname(), 'tmp')
 219         if 'S' in flags:
 220             # If a message has been seen, it goes into the cur
 221             # directory.  CR debian#152482, [complete.org #4]
 222             newpath = os.path.join(self.getfullname(), 'cur')
 223         else:
 224             newpath = os.path.join(self.getfullname(), 'new')
 225         infostr = ':'
 226         infomatch = re.search('(:.*)$', newname)
 227         if infomatch:                   # If the info string is present..
 228             infostr = infomatch.group(1)
 229             newname = newname.split(':')[0] # Strip off the info string.
 230         infostr = re.sub('2,[A-Z]*', '', infostr)
 231         flags.sort()
 232         infostr += '2,' + ''.join(flags)
 233         newname += infostr
 234
 235         newfilename = os.path.join(newpath, newname)
 236         if (newfilename != oldfilename):
 237             os.rename(oldfilename, newfilename)
 238             self.messagelist[uid]['flags'] = flags
 239             self.messagelist[uid]['filename'] = newfilename
 240
 241         # By now, the message had better not be in tmp/ land!
 242         final_dir, final_name = os.path.split(self.messagelist[uid]['filename'])
 243         assert final_dir != tmpdir
 244
 245     def deletemessage(self, uid):
 246         if not uid in self.messagelist:
 247             return
 248         filename = self.messagelist[uid]['filename']
 249         try:
 250             os.unlink(filename)
 251         except OSError:
 252             # Can't find the file -- maybe already deleted?
 253             newmsglist = self._scanfolder()
 254             if uid in newmsglist:       # Nope, try new filename.
 255                 os.unlink(newmsglist[uid]['filename'])
 256             # Yep -- return.
 257         del(self.messagelist[uid])
 258