diff options
-rwxr-xr-x | archivemail.py | 40 |
1 files changed, 35 insertions, 5 deletions
diff --git a/archivemail.py b/archivemail.py index fbbbc28..bdc26f5 100755 --- a/archivemail.py +++ b/archivemail.py @@ -67,6 +67,7 @@ import tempfile import time import urlparse import errno +import socket # From_ mangling regex. from_re = re.compile(r'^From ', re.MULTILINE) @@ -393,7 +394,6 @@ class Mbox(mailbox.UnixMailbox): def _dotlock_lock(self): """Create a dotlock file for the 'mbox' mailbox""" - import socket hostname = socket.gethostname() pid = os.getpid() box_dir, prelock_prefix = os.path.split(self.mbox_file_name) @@ -460,7 +460,14 @@ class ArchiveMbox: def append(self, filename): """Append the content of the given file to the mbox.""" fin = open(filename, "r") - shutil.copyfileobj(fin, self.mbox_file) + oldsize = os.fstat(self.mbox_file.fileno()).st_size + try: + shutil.copyfileobj(fin, self.mbox_file) + except: + # We can safely abort here without data loss, because + # we have not yet changed the original mailbox + self.mbox_file.truncate(oldsize) + raise fin.close() def close(self): @@ -529,6 +536,12 @@ class TempMbox: vprint("closing file '%s'" % self.mbox_file_name) self.mbox_file.close() + def saveas(self, filename): + """Rename this temporary mbox file to the given name, making it + permanent. Emergency use only.""" + os.rename(self.mbox_file_name, filename) + _stale.temp_mboxes.remove(retain.mbox_file_name) + def remove(self): """Delete the temporary mbox file.""" os.remove(self.mbox_file_name) @@ -1126,14 +1139,29 @@ def _archive_mbox(mailbox_name, final_archive_name): if original.starting_size != original.get_size(): unexpected_error("the mailbox '%s' changed size during reading!" % \ mailbox_name) + # Write the new archive before modifying the mailbox, to prevent + # losing data if something goes wrong commit_archive(archive, final_archive_name) if retain: pending_changes = original.mbox_file.tell() != retain.mbox_file.tell() retain.close() if pending_changes: - vprint("overwriting mbox '%s' with temporary mbox '%s'" % \ - (original.mbox_file_name, retain.mbox_file_name)) - original.overwrite_with(retain.mbox_file_name) + vprint("writing back changed mailbox '%s'..." % \ + original.mbox_file_name) + # Prepare for recovery on error. + # FIXME: tempfile.tempdir is our nested dir. + saved_name = "%s/%s.%s.%s-%s-%s" % \ + (tempfile.tempdir, options.script_name, + os.path.basename(original.mbox_file_name), + socket.gethostname(), os.getuid(), + os.getpid()) + try: + original.overwrite_with(retain.mbox_file_name) + except: + retain.saveas(saved_name) + print "Error writing back changed mailbox; saved good copy to " \ + "%s" % saved_name + raise else: vprint("no changes to mbox '%s'" % original.mbox_file_name) retain.remove() @@ -1185,6 +1213,8 @@ def _archive_dir(mailbox_name, final_archive_name, type): else: vprint("decision: retain message") vprint("finished reading messages") + # Write the new archive before modifying the mailbox, to prevent + # losing data if something goes wrong commit_archive(archive, final_archive_name) for file_name in delete_queue: vprint("removing original message: '%s'" % file_name) |