Thanks Timo.
I was writing out corrupted dovecot-uidlist files, fixing that solved the issue.
Attached is a script that fixes message names. It's not fully QA'ed yet, and
uses some of our site-specific stuff to figure out who owns the maildir and to
boot the user while making changes, but might be useful as a starting point.
Note that it handles compressed and uncompressed messages.
#!/usr/bin/perl
use strict;
use warnings;
package MaildirSizeFix;
=head1 SYNOPSIS
MaildirSizeFix - library and utility for checking and fixing message size in
maildir filenames
=head2 Library
MaildirSizeFix::fixmaildir(<maildir>, [<filehandle>]);
Find all mail folders in <maildir> (including '.', the INBOX folder) and call
fixfolder() on each. Print log messages to <filehandle> if provided.
MaildirSizeFix::fixfolder(<folder>, [<filehandle>]);
Find all mail message files in the cur and new subdirectories of <folder>,
compare the filename size and actual message size and if necessary
rename the file. Also updates file names in dovecot-uidlist.
Print log messages to <filehandle> if provided.
Locks the maildir and boots the user if changes need to be made.
=head2 Command Line
MaildirSizeFix.pm
[--maildir=<maildir>] [--folder=<folder>] [--help]
--maildir call fixmaildir on <maildir>
--folder call fixfolder on <folder>
Where maildir, folder and are full directory paths.
=head2 Note
For both command line and library usage, the environment variable
MAILDIRLOCK_BIN _must_ be set to the location of
the maildirlock binary from dovecot source. LD_LIBRARY_PATH will most
likely also have to be set to include libdovecot.
=cut
use IO::Zlib qw(:gzip_external 0);
use IO::Socket::INET;
use File::Basename;
use Getopt::Long;
use Pod::Usage;
sub fixmaildir($;$)
{
my ($dir, $outh) = @_;
die "Cannot access maildir [$dir]" unless ($dir && -d $dir);
my @folders = sort (grep { $_ !~ /\/..$/ } glob("$dir/.*"));
for my $f (@folders) # cur and new in every folder
{
_pout($outh, "FOLDER: [$f]\n");
fixfolder($f, $outh);
}
}
sub fixfolder($;$)
{
my ($folder, $outh) = @_;
# find files to rename
# lock maildir
# boot user
# rename files
# update dovecot-uidlist
# unlock maildir
unless ($folder && -d $folder)
{
_pout($outh, "DIRBAD: [$folder]\n");
return;
}
my %renames = _check_folder($folder, $outh);
if (%renames)
{
my $lock;
unless ($lock = _lock_maildir($folder))
{
_pout($outh, "LOCKBAD: [$folder]\n");
return;
}
_reap_owner($folder, $outh);
while (my ($old, $new) = each %renames)
{
if (rename("$old", "$new"))
{
_pout($outh, "FIXED: [$old] => [$new]\n");
}
else
{
_pout($outh, "RENAMEBAD: [$old] => [$new]: $!\n");
delete $renames{$old};
}
}
_fix_uidlist($folder, %renames);
_unlock_maildir($lock);
}
}
sub _check_folder($;$)
{
my ($folder, $outh) = @_;
my %renames = ();
for my $d (map {"$folder/$_"} qw(cur new))
{
opendir (my $dh, $d) || next; # TODO log error?
while (my $f = readdir($dh)) # every message file
{
my $fullpath = "$d/$f";
next unless -f $fullpath;
my ($filen_size) = $f =~ /S=(\d*)/;
next unless $filen_size;
my $quick_size = _uncompressed_size_quick($fullpath);
if (!defined $quick_size)
{
_pout($outh, "\tBAD1: [$fullpath]\n");
next;
}
if ($filen_size != $quick_size)
{
my ($actual_size, $actual_wsize) = _uncompressed_size($fullpath);
if (!defined $actual_size)
{
_pout($outh, "\tBAD2: [$fullpath]\n");
next;
}
my $newname = $f;
$newname =~ s/,S=(\d*)|,W=(\d*)//g; #remove old sizes if present
$newname =~ s/:2/,S=$actual_size,W=$actual_wsize:2/;
$renames{"$d/$f"} = "$d/$newname";
}
}
}
return %renames;
}
sub _lock_maildir($)
{
my ($folder) = @_;
my $lockbin = $ENV{MAILDIRLOCK_BIN};
open my $output, "-|", $lockbin, ($folder, "30") or return 0;
my $pid = <$output>;
close $output;
return $pid;
}
sub _unlock_maildir($)
{
my ($lock) = @_;
return unless $lock;
kill 15, $lock;
return;
}
sub _reap_owner($;$)
{
my ($folder, $outh) = @_;
my ($owner) = $folder =~ qr(/\d\d\d/\d\d\d/(.*?)/);
return unless $owner;
my $sock = IO::Socket::INET->new(PeerAddr=>'imap:1313', Proto=>'tcp');
return unless $sock;
scalar(<$sock>); # read banner
print $sock "GLOBAL KILL $owner\r\n";
$sock->autoflush();
close($sock);
}
sub _fix_uidlist($%)
{
my ($folder, %renames) = @_;
my $fn = "$folder/dovecot-uidlist";
return unless %renames;
open (my $fh, '+<', $fn) or return;
my $list = do { local $/; <$fh> }; # slurp whole file
while (my ($old, $new) = each %renames)
{
$old = basename($old);
$new = basename($new);
$list =~ s/$old/$new/;
}
truncate ($fh, 0);
seek($fh, 0,0);
print $fh $list;
close ($fh);
}
sub _pout($@)
{
my $h = shift;
print $h @_ if $h;
}
# get the message size, either from the last 4 bytes if compressed, or file size
sub _uncompressed_size_quick($)
{
my ($fn) = @_;
my $gzid = chr(0x1f) . chr(0x8b);
my ($flag, $buf);
open(my $fh, '<', $fn) or return undef;
return undef unless (sysread($fh, $flag, 2) == 2);
unless ($flag eq $gzid) # not a compressed file, return the size-on-disk
{
return sysseek($fh, 0, 2);
}
# gziped file, size is in last 4 bytes
return undef unless (sysseek($fh, -4, 2));
return undef unless (sysread($fh, $buf, 4));
return unpack('V', $buf);
}
# get the S= and W= size by reading the whole file.
sub _uncompressed_size($)
{
my $fn = $_[0];
my $fh = IO::Zlib->new($fn, "rb") || IO::File->new("< $fn");
return undef unless $fh;
my $sz = 0; #uncompressed size
my $wsz = 0; #uncompressed size with /n converted to /r/n
my $read;
my $chunk = 4096; # TODO tune
my $buf;
my $cusp = 0;
while ($read = read($fh, $buf, $chunk))
{
$sz += $read;
$wsz += $read;
$wsz += () = $buf =~ /(?<!\r)\n/sg; #count \ns not preceded by an \r
if ($cusp)
{
# last chunk ended with \r and this chunk starts with \n, so we counted
# an /n we shouldn't have above
$wsz -=1 if ($buf =~ /^\n/s);
}
$cusp = $buf =~ /\r$/s;
}
return ($sz, $wsz);
}
unless(caller())
{
my ($maildir, $folder, $mail, $lockbin);
GetOptions(
"maildir=s" => \$maildir,
"folder=s" => \$folder,
"help" => sub {pod2usage(-verbose =>1 )},
"man" => sub {pod2usage(-verbose =>2 )})
|| pod2usage(-verbose => 1);
$lockbin = $ENV{MAILDIRLOCK_BIN};
pod2usage(-verbose=>1) unless ($lockbin && ($maildir || $folder || $mail));
die "Could not execute maildirlock [$lockbin]" unless -x $lockbin;
system("$lockbin >/dev/null 2>&1 ");
die "Could not execute maildirlock [$lockbin], " .
"maybe you need to set LD_LIBRARY_PATH" unless ($? >> 8) == 1;
if ($maildir)
{
print "Fixing maildir: [$maildir]\n";
fixmaildir($maildir, \*STDOUT);
}
if ($folder)
{
print "Fixing folder: [$folder]\n";
fixfolder($folder, \*STDOUT);
}
}
1;
On 2013-01-22, at 7:01 AM, Timo Sirainen <t...@iki.fi> wrote:
> On 21.1.2013, at 21.54, Richard Platel <rpla...@tucows.com> wrote:
>
>> As stated in my previous message, we have some old compressed maildir
>> messages with incorrect sizes in the filename. These messages cause dovecot
>> 2.x problems.
>>
>> I'm trying to write a script to crawl all our messages, check the actual
>> message size and if necessary, fix the filename. However, when I do this,
>> dovecot gives the message a new UID on next login. If I change the filename
>> in dovecot-uidlist, dovecot still gives a new UID on next login. If I
>> change dovecot-uidlist and delete the index, then the UID is preserved.
>
> I don't really understand why deleting dovecot.index* would make a difference
> here, except maybe as a workaround in case the user has that mailbox
> selected, because the filenames could be cached in memory.
>
> http://dovecot.org/tools/maildir-size-fix.pl
> http://dovecot.org/tools/maildir-size-check.sh
>
> Those scripts kind of do what you want, except not fully, so it would be nice
> to get one fully finished one :) The best way for the script to would would
> be to:
>
> * scan through a maildir, figure out what needs to be renamed to what, but
> don't actually do it
> * lock the maildir with dovecot-uidlist.lock (src/util/maildirlock comes with
> dovecot)
> * doveadm kick user's imap/pop3 sessions, and even better if it was possible
> to kill -9 any pending processes
> * rename the files and update dovecot-uidlist
> * delete dovecot-uidlist.lock
>
> This separately for each folder.
>
