Merge branch 'master' into debian

4 files changed, 105 insertions, 121 deletions

diff --git a/imapsync b/imapsync
index fec37f0..339979c 100755
--- a/imapsync
+++ b/imapsync
@@ -47,7 +47,6 @@ sub usage(;$) {
         print STDERR "Synchronize the given MAILBOXes between two QRESYNC-capable IMAP4rev1 servers.\n"
             ."Options:\n"
             ."    --config=FILE    Specify an alternate configuration file\n"
-            ."    -1, --oneshot    Exit as soon as all mailboxes are synchronized\n"
             ."    --repair         List the database anomalies and try to repair them\n"
             ."    -q, --quiet      Try to be quiet\n"
             ."    --debug          Turn on debug mode\n"
@@ -55,7 +54,7 @@ sub usage(;$) {
     }
     exit $rv;
 }
-usage(1) unless GetOptions(\%CONFIG, qw/config=s quiet|q oneshot|1 repair debug help|h/);
+usage(1) unless GetOptions(\%CONFIG, qw/config=s quiet|q repair debug help|h/);
 usage(0) if $CONFIG{help};
 
 
@@ -93,13 +92,13 @@ my $DBH;
 
 # Clean after us
 sub cleanup() {
-    logger("Cleaning up...") if $CONFIG{debug};
+    logger(undef, "Cleaning up...") if $CONFIG{debug};
     unlink $LOCKFILE if defined $LOCKFILE and -f $LOCKFILE;
     close $LOGGER_FD if defined $LOGGER_FD;
     $DBH->disconnect() if defined $DBH;
 }
-$SIG{$_} = sub { cleanup(); msg($!); exit 1; } foreach qw/INT TERM/;
-$SIG{$_} = sub { cleanup(); msg($!); exit 0; } foreach qw/HUP/;
+$SIG{$_} = sub { msg(undef, $!); cleanup(); exit 1; } foreach qw/INT TERM/;
+$SIG{$_} = sub { msg(undef, $!); cleanup(); exit 0; } foreach qw/HUP/;
 
 
 #############################################################################
@@ -224,7 +223,9 @@ foreach my $name (qw/local remote/) {
     #my $mailboxes = $client->list((uc $config{'subscribed-only'} eq 'TRUE' ? '(SUBSCRIBED)' : '' )
     #                             .$config{mailboxes}, 'SUBSCRIBED');
     # $client->notify('SELECTED', 'MAILBOXES ('.join(' ', keys %$mailboxes).')');
-    $client->notify(qw/SELECTED SUBSCRIBED/) unless $CONFIG{oneshot};
+    # XXX NOTIFY doesn't work as expected for INBOX
+    #     http://dovecot.org/pipermail/dovecot/2015-July/101514.html
+    #$client->notify(qw/SELECTED SUBSCRIBED/) if $CONFIG{watch};
     # XXX We shouldn't need to ask for STATUS responses here, and use
     #     NOTIFY's STATUS indicator instead.  However Dovecot violates RFC
     #     5464: http://dovecot.org/pipermail/dovecot/2015-July/101474.html
@@ -337,7 +338,8 @@ sub sync_tree($$%) {
                 # $missing's $mbx2, which is not in the database and
                 # doesn't exist on $exists
                 msg($exists, "Rename mailbox $mbx to $mbx2[0]");
-                $sth->{rename}->execute($mbx2[0],$idx);
+                $sth->{rename}->execute($mbx2[0],$idx) or
+                    msg('database', "WARNING: Can't rename $mbx to $mbx2[0]");
                 $IMAP->{$exists}->{client}->rename($mbx, $mbx2[0]);
                 $DBH->commit();
                 mv_tree($IMAP->{$exists}->{mailboxes}, $mbx, $mbx2[0], %children);
@@ -375,7 +377,8 @@ sub sync_tree($$%) {
                 # database as associated with $mbx2, which exists on
                 # $missing but not on $exists
                 msg($missing, "Rename mailbox $mbx2 to $mbx");
-                $sth->{rename}->execute($mbx,$idx);
+                $sth->{rename}->execute($mbx,$idx) or
+                    msg('database', "WARNING: Can't rename $mbx2 to $mbx2");
                 $IMAP->{$missing}->{client}->rename($mbx2, $mbx);
                 $DBH->commit();
                 mv_tree($IMAP->{$missing}->{mailboxes}, $mbx2, $mbx, %children);
@@ -419,7 +422,7 @@ sub sync_tree($$%) {
         foreach qw/local remote/;
     $sth{$_.'_by_uidvalidity'} = $DBH->prepare("SELECT idx,mailbox FROM mailboxes NATURAL JOIN $_ WHERE UIDVALIDITY = ?")
         foreach qw/local remote/;
-    $sth{rename} = $DBH->prepare("UPDATE mailboxes SET mailbox = ? WHERE idx = ?");
+    $sth{rename} = $DBH->prepare(q{UPDATE mailboxes SET mailbox = ? WHERE idx = ?});
 
     my $updated = 0;
     while (my ($mbx,$children) = each %$tree) {
@@ -442,78 +445,72 @@ sub sync_tree($$%) {
     }
 }
 
-# Syncronize subscription list
+# Synchronize subscription list
 my @SUBSCRIPTIONS;
 {
-    my $sth_search = $DBH->prepare("SELECT idx,subscribed FROM mailboxes WHERE mailbox = ?");
-    my $sth_subscribe = $DBH->prepare("UPDATE mailboxes SET subscribed = ? WHERE idx = ?");
+    my $sth_search = $DBH->prepare(q{SELECT idx,subscribed FROM mailboxes WHERE mailbox = ?});
+    my $sth_subscribe = $DBH->prepare(q{UPDATE mailboxes SET subscribed = ? WHERE idx = ?});
 
     my %mailboxes;
     $mailboxes{$_} = 1 foreach (keys %{$IMAP->{local}->{mailboxes}}, keys %{$IMAP->{remote}->{mailboxes}});
 
     foreach my $mbx (keys %mailboxes) {
-        if (subscribed_mbx('local',$mbx) xor subscribed_mbx('remote',$mbx)) {
-            my ($subscribed,$unsubscribed) = subscribed_mbx('local',$mbx) ? ('local','remote') : ('remote','local');
-
-            $sth_search->execute($mbx);
-            my $row = $sth_search->fetch();
-            die if defined $sth_search->fetch(); # sanity check
+        $sth_search->execute($mbx);
+        my $row = $sth_search->fetch();
+        die if defined $sth_search->fetch(); # sanity check
 
+        my ($lSubscribed,$rSubscribed) = map {subscribed_mbx($_,$mbx)} qw/local remote/;
+        if ($lSubscribed == $rSubscribed) {
+            if (defined $row) {
+                my ($idx,$status) = @$row;
+                if (defined $status and $status != $lSubscribed) {
+                    $sth_subscribe->execute($lSubscribed, $idx) or
+                        msg('database', "WARNING: Can't (un)subscribe $mbx");
+                    $DBH->commit();
+                }
+            }
+        }
+        else {
+            my ($subscribed,$unsubscribed) = $lSubscribed ? qw/local remote/ : qw/remote local/;
             if (defined $row) {
                 my ($idx,$status) = @$row;
                 if ($status) {
                     # $mbx was SUBSCRIBEd before, UNSUBSCRIBE it now
                     msg($subscribed, "Unsubscribe to mailbox $mbx");
-                    $sth_subscribe->execute(0,$idx);
+                    $sth_subscribe->execute(0,$idx) or
+                        msg('database', "WARNING: Can't unsubscribe $mbx");
                     $IMAP->{$subscribed}->{client}->unsubscribe($mbx);
                     $DBH->commit();
-                    $IMAP->{$subscribed}->{mailboxes}->{$mbx} =
-                        grep {lc $_ ne lc '\Subscribed'} @{$IMAP->{$subscribed}->{mailboxes}->{$mbx} // []};
+                    $lSubscribed = $rSubscribed = 0;
                 }
                 else {
                     # $mbx was UNSUBSCRIBEd before, SUBSCRIBE it now
                     msg($unsubscribed, "Subscribe to mailbox $mbx");
-                    $sth_subscribe->execute(1,$idx);
+                    $sth_subscribe->execute(1,$idx) or
+                        msg('database', "WARNING: Can't subscribe $mbx");
                     $IMAP->{$unsubscribed}->{client}->subscribe($mbx);
                     $DBH->commit();
-                    $IMAP->{$unsubscribed}->{mailboxes}->{$mbx} //= [];
-                    push @{$IMAP->{$unsubscribed}->{mailboxes}->{$mbx}}, '\Subscribed';
+                    $lSubscribed = $rSubscribed = 1;
                 }
             }
             else {
                 # $mbx is unknown; assume the user wants to SUBSCRIBE
                 msg($unsubscribed, "Subscribe to mailbox $mbx");
                 $IMAP->{$unsubscribed}->{client}->subscribe($mbx);
-                $IMAP->{$unsubscribed}->{mailboxes}->{$mbx} //= [];
-                push @{$IMAP->{$unsubscribed}->{mailboxes}->{$mbx}}, '\Subscribed';
+                $lSubscribed = $rSubscribed = 1;
             }
         }
-        else {
-            $sth_search->execute($mbx);
-            my $row = $sth_search->fetch();
-            die if defined $sth_search->fetch(); # sanity check
-
-            if (defined $row) {
-                my ($idx,$status) = @$row;
-                unless (defined $status and $status != 0) {
-                    my $subscribed = subscribed_mbx('local',$mbx) ? 1 : 0;
-                    $sth_subscribe->execute($subscribed, $idx);
-                    $DBH->commit();
-                }
-            }
-        }
-        push @SUBSCRIPTIONS, $mbx if subscribed_mbx('local', $mbx) and
-                                     subscribed_mbx('remote',$mbx);
+        push @SUBSCRIPTIONS, $mbx if $lSubscribed;
     }
 }
 
 # Clean database: remove mailboxes that no longer exist
 {
-    my $sth = $DBH->prepare("SELECT idx,mailbox,subscribed FROM mailboxes");
-    my $sth_delete_mailboxes = $DBH->prepare("DELETE FROM mailboxes WHERE idx = ?");
-    my $sth_delete_local     = $DBH->prepare("DELETE FROM local     WHERE idx = ?");
-    my $sth_delete_remote    = $DBH->prepare("DELETE FROM remote    WHERE idx = ?");
-    my $sth_delete_mapping   = $DBH->prepare("DELETE FROM mapping   WHERE idx = ?");
+    my $sth = $DBH->prepare(q{SELECT idx,mailbox,subscribed FROM mailboxes});
+    my $sth_delete_mailboxes = $DBH->prepare(q{DELETE FROM mailboxes WHERE idx = ?});
+    my $sth_delete_local     = $DBH->prepare(q{DELETE FROM local     WHERE idx = ?});
+    my $sth_delete_remote    = $DBH->prepare(q{DELETE FROM remote    WHERE idx = ?});
+    my $sth_delete_mapping   = $DBH->prepare(q{DELETE FROM mapping   WHERE idx = ?});
 
     my @idx;
     $sth->execute();
@@ -620,7 +617,7 @@ sub download_missing($$$@) {
         my $uid = $mail->{UID};
         my $from = first { defined $_ and @$_ } @{$mail->{ENVELOPE}}[2,3,4];
         $from = (defined $from and @$from) ? $from->[0]->[2].'@'.$from->[0]->[3] : '';
-        msg("$source($mailbox): UID $uid from <$from> ($mail->{INTERNALDATE})") unless $CONFIG{quiet};
+        msg(undef, "$source($mailbox): UID $uid from <$from> ($mail->{INTERNALDATE})") unless $CONFIG{quiet};
 
         callback_new_message($idx, $mailbox, $source, $mail, \@uids, $buff, \$bufflen)
     });
@@ -631,12 +628,12 @@ sub download_missing($$$@) {
 
 # Solve a flag update conflict (by taking the union of the two flag lists).
 sub flag_conflict($$$$$) {
-    my ($mailbox, $lUID, $lFlags, $rUID, $rFlags);
+    my ($mailbox, $lUID, $lFlags, $rUID, $rFlags) = @_;
 
     my %flags = map {$_ => 1} (split(/ /, $lFlags), split(/ /, $rFlags));
     my $flags = join ' ', sort(keys %flags);
-    msg("WARNING: Conflicting flag update in $mailbox for local UID $lUID ($lFlags) ".
-        "and remote UID $rUID ($rFlags). Setting both to the union ($flags).");
+    msg(undef, "WARNING: Conflicting flag update in $mailbox for local UID $lUID ($lFlags) ".
+               "and remote UID $rUID ($rFlags). Setting both to the union ($flags).");
 
     return $flags
 }
@@ -647,7 +644,7 @@ sub delete_mapping($$) {
     my ($idx, $lUID) = @_;
     my $r = $STH_DELETE_MAPPING->execute($idx, $lUID);
     die if $r > 1; # sanity check
-    msg("WARNING: Can't delete (idx,lUID) = ($idx,$lUID) from the database") if $r == 0;
+    msg('database', "WARNING: Can't delete (idx,lUID) = ($idx,$lUID)") if $r == 0;
 }
 
 
@@ -699,7 +696,7 @@ sub repair($$) {
             }
             else {
                 # conflict
-                msg("WARNING: Missed flag update in $mailbox for (lUID,rUID) = ($lUID,$rUID). Repairing.")
+                msg(undef, "WARNING: Missed flag update in $mailbox for (lUID,rUID) = ($lUID,$rUID). Repairing.")
                     if $lModified->{$lUID}->[0] <= $cache->{lHIGHESTMODSEQ} and
                        $rModified->{$rUID}->[0] <= $cache->{rHIGHESTMODSEQ};
                 # set both $lUID and $rUID to the union of $lFlags and $rFlags
@@ -712,7 +709,7 @@ sub repair($$) {
         }
         elsif (!defined $lModified->{$lUID} and !defined $rModified->{$rUID}) {
             unless ($lVanished{$lUID} and $rVanished{$rUID}) {
-                msg("WARNING: Pair (lUID,rUID) = ($lUID,$rUID) vanished from $mailbox. Repairing.");
+                msg(undef, "WARNING: Pair (lUID,rUID) = ($lUID,$rUID) vanished from $mailbox. Repairing.");
                 push @delete_mapping, $lUID;
             }
         }
@@ -721,7 +718,7 @@ sub repair($$) {
             if ($lVanished{$lUID}) {
                 push @rToRemove, $rUID;
             } else {
-                msg("local($mailbox): WARNING: UID $lUID disappeared. Downloading remote UID $rUID again.");
+                msg("local($mailbox)", "WARNING: UID $lUID disappeared. Downloading remote UID $rUID again.");
                 push @rMissing, $rUID;
             }
         }
@@ -730,7 +727,7 @@ sub repair($$) {
             if ($rVanished{$rUID}) {
                 push @lToRemove, $lUID;
             } else {
-                msg("remote($mailbox): WARNING: UID $rUID disappeared. Downloading local UID $lUID again.");
+                msg("remote($mailbox)", "WARNING: UID $rUID disappeared. Downloading local UID $lUID again.");
                 push @lMissing, $lUID;
             }
         }
@@ -759,15 +756,15 @@ sub repair($$) {
 
 
     # Process UID found in IMAP but not in the mapping table.
-    msg("remote($mailbox): WARNING: No match for vanished local UID $_. Ignoring.") foreach keys %lVanished;
-    msg("local($mailbox): WARNING: No match for vanished remote UID $_. Ignoring.") foreach keys %rVanished;
+    msg("remote($mailbox)", "WARNING: No match for vanished local UID $_. Ignoring.") foreach keys %lVanished;
+    msg("local($mailbox)", "WARNING: No match for vanished remote UID $_. Ignoring.") foreach keys %rVanished;
 
     foreach my $lUID (keys %$lModified) {
-        msg("remote($mailbox): WARNING: No match for modified local UID $lUID. Downloading again.");
+        msg("remote($mailbox)", "WARNING: No match for modified local UID $lUID. Downloading again.");
         push @lMissing, $lUID;
     }
     foreach my $rUID (keys %$rModified) {
-        msg("local($mailbox): WARNING: No match for modified remote UID $rUID. Downloading again.");
+        msg("local($mailbox)", "WARNING: No match for modified remote UID $rUID. Downloading again.");
         push @rMissing, $rUID;
     }
 
@@ -815,7 +812,7 @@ sub sync_known_messages($$) {
                 my ($rUID) = $STH_GET_REMOTE_UID->fetchrow_array();
                 die if defined $STH_GET_REMOTE_UID->fetchrow_arrayref(); # sanity check
                 if (!defined $rUID) {
-                    msg("remote($mailbox): WARNING: No match for vanished local UID $lUID. Ignoring.");
+                    msg("remote($mailbox)", "WARNING: No match for vanished local UID $lUID. Ignoring.");
                 }
                 elsif (!exists $rVanished{$rUID}) {
                     push @rToRemove, $rUID;
@@ -826,7 +823,7 @@ sub sync_known_messages($$) {
                 my ($lUID) = $STH_GET_LOCAL_UID->fetchrow_array();
                 die if defined $STH_GET_LOCAL_UID->fetchrow_arrayref(); # sanity check
                 if (!defined $lUID) {
-                    msg("local($mailbox): WARNING: No match for vanished remote UID $rUID. Ignoring.");
+                    msg("local($mailbox)", "WARNING: No match for vanished remote UID $rUID. Ignoring.");
                 }
                 elsif (!exists $lVanished{$lUID}) {
                     push @lToRemove, $lUID;
@@ -861,7 +858,7 @@ sub sync_known_messages($$) {
                 my ($rUID) = $STH_GET_REMOTE_UID->fetchrow_array();
                 die if defined $STH_GET_REMOTE_UID->fetchrow_arrayref(); # sanity check
                 if (!defined $rUID) {
-                    msg("remote($mailbox): WARNING: No match for modified local UID $lUID. Try '--repair'.");
+                    msg("remote($mailbox)", "WARNING: No match for modified local UID $lUID. Try '--repair'.");
                 }
                 elsif (defined (my $rFlags = $rModified->{$rUID})) {
                     unless ($lFlags eq $rFlags) {
@@ -882,7 +879,7 @@ sub sync_known_messages($$) {
                 my ($lUID) = $STH_GET_LOCAL_UID->fetchrow_array();
                 die if defined $STH_GET_LOCAL_UID->fetchrow_arrayref(); # sanity check
                 if (!defined $lUID) {
-                    msg("local($mailbox): WARNING: No match for modified remote UID $rUID. Try '--repair'.");
+                    msg("local($mailbox)", "WARNING: No match for modified remote UID $rUID. Try '--repair'.");
                 }
                 elsif (!exists $lModified->{$lUID}) {
                     # conflicts are taken care of above
@@ -915,7 +912,7 @@ sub callback_new_message($$$$;$$$) {
 
     my $length = length $mail->{RFC822};
     if ($length == 0) {
-        msg("$name($mailbox): WARNING: Ignoring new 0-length message (UID $mail->{UID})");
+        msg("$name($mailbox)", "WARNING: Ignoring new 0-length message (UID $mail->{UID})");
         return;
     }
 
@@ -951,7 +948,8 @@ sub callback_new_message_flush($$$@) {
 
     my ($lUIDs, $rUIDs) = $name eq 'local' ? (\@sUID,\@tUID) : (\@tUID,\@sUID);
     for (my $k=0; $k<=$#messages; $k++) {
-        logger("Adding mapping (lUID,rUID) = ($lUIDs->[$k],$rUIDs->[$k]) for $mailbox") if $CONFIG{debug};
+        logger(undef, "Adding mapping (lUID,rUID) = ($lUIDs->[$k],$rUIDs->[$k]) for $mailbox")
+            if $CONFIG{debug};
         $STH_INSERT_MAPPING->execute($idx, $lUIDs->[$k], $rUIDs->[$k]);
     }
     $DBH->commit(); # commit only once per batch
@@ -965,26 +963,32 @@ sub callback_new_message_flush($$$@) {
 # the given UIDs.
 sub sync_messages($$;$$) {
     my ($idx, $mailbox, $lIgnore, $rIgnore) = @_;
-    my ($buff, $bufflen, @lUIDs);
-
-    # get new messages from remote (except @$rIgnore) and APPEND them to local
-    ($buff, $bufflen) = ([], 0);
-    undef $buff if $lIMAP->incapable('MULTIAPPEND');
-    $rIMAP->pull_new_messages(sub($) {
-        callback_new_message($idx, $mailbox, 'remote', shift, \@lUIDs, $buff, \$bufflen)
-    }, @{$rIgnore // []});
-    push @lUIDs, callback_new_message_flush($idx, $mailbox, 'remote', @$buff)
-        if defined $buff and @$buff;
-
-    # get new messages from local (except @$lIgnore and the newly allocated local
-    # UIDs @lUIDs) and APPEND them to remote
-    ($buff, $bufflen) = ([], 0);
-    undef $buff if $rIMAP->incapable('MULTIAPPEND');
-    $lIMAP->pull_new_messages(sub($) {
-        callback_new_message($idx, $mailbox, 'local', shift, undef, $buff, \$bufflen)
-    }, @{$lIgnore // []}, @lUIDs);
-    callback_new_message_flush($idx, $mailbox, 'local', @$buff)
-        if defined $buff and @$buff;
+
+    my %ignore = (local => ($lIgnore // []), remote => ($rIgnore // []));
+    my $loop;
+    do {
+        # get new messages from $source (except @{$ignore{$source}}) and APPEND them to $target
+        foreach my $source (qw/remote local/) { # pull remote mails first
+            my $target = $source eq 'remote' ? 'local' : 'remote';
+            my $buff    = [] unless ($target eq 'local' ? $lIMAP : $rIMAP)->incapable('MULTIAPPEND');
+            my $bufflen = 0;
+            my @tUIDs;
+
+            ($source eq 'remote' ? $rIMAP : $lIMAP)->pull_new_messages(sub($) {
+                callback_new_message($idx, $mailbox, $source, shift, \@tUIDs, $buff, \$bufflen)
+            }, @{$ignore{$source}});
+
+            push @tUIDs, callback_new_message_flush($idx, $mailbox, $source, @$buff)
+                if defined $buff and @$buff;
+            push @{$ignore{$target}}, @tUIDs;
+
+            $loop = @tUIDs ? 1 : 0;
+        }
+        # since $source modifies $target's UIDNEXT upon new mails, we
+        # need to check again the first $source (remote) whenever the
+        # last one (local) added new messages to it
+    }
+    while ($loop);
 
     # both local and remote UIDNEXT are now up to date; proceed with
     # pending flag updates and vanished messages
@@ -992,8 +996,10 @@ sub sync_messages($$;$$) {
 
     # don't store the new UIDNEXTs before to avoid downloading these
     # mails again in the event of a crash
-    $STH_UPDATE_LOCAL->execute($lIMAP->get_cache( qw/UIDNEXT HIGHESTMODSEQ/), $idx);
-    $STH_UPDATE_REMOTE->execute($rIMAP->get_cache(qw/UIDNEXT HIGHESTMODSEQ/), $idx);
+    $STH_UPDATE_LOCAL->execute($lIMAP->get_cache( qw/UIDNEXT HIGHESTMODSEQ/), $idx) or
+        msg('database', "WARNING: Can't update remote UIDNEXT/HIGHESTMODSEQ for $mailbox");
+    $STH_UPDATE_REMOTE->execute($rIMAP->get_cache(qw/UIDNEXT HIGHESTMODSEQ/), $idx) or
+        msg('database', "WARNING: Can't update remote UIDNEXT/HIGHESTMODSEQ for $mailbox");
     $DBH->commit();
 }
 
@@ -1023,7 +1029,7 @@ my ($MAILBOX, $IDX);
 $STH_LIST_INTERRUPTED->execute();
 while (defined (my $row = $STH_LIST_INTERRUPTED->fetchrow_arrayref())) {
     ($IDX, $MAILBOX) = @$row;
-    msg("Resuming interrupted sync for $MAILBOX");
+    msg(undef, "Resuming interrupted sync for $MAILBOX");
 
     my %lUIDs;
     $STH_GET_INTERRUPTED_BY_IDX->execute($IDX);
@@ -1098,10 +1104,7 @@ while (@REPAIR) {
     $rIMAP->select($MAILBOX);
     repair($IDX, $MAILBOX);
 }
-if ($CONFIG{repair}) {
-    cleanup();
-    exit 0;
-}
+exit 0 if $CONFIG{repair};
 
 
 while(1) {
@@ -1139,18 +1142,17 @@ while(1) {
             elsif (sync_known_messages($IDX, $MAILBOX)) {
                 # sync updates to known messages before fetching new messages
                 # get_cache is safe after pull_update
-                $STH_UPDATE_LOCAL_HIGHESTMODSEQ->execute( $lIMAP->get_cache('HIGHESTMODSEQ'), $IDX);
-                $STH_UPDATE_REMOTE_HIGHESTMODSEQ->execute($rIMAP->get_cache('HIGHESTMODSEQ'), $IDX);
+                $STH_UPDATE_LOCAL_HIGHESTMODSEQ->execute( $lIMAP->get_cache('HIGHESTMODSEQ'), $IDX) or
+                    msg('database', "WARNING: Can't update local HIGHESTMODSEQ for $MAILBOX");
+                $STH_UPDATE_REMOTE_HIGHESTMODSEQ->execute($rIMAP->get_cache('HIGHESTMODSEQ'), $IDX) or
+                    msg('database', "WARNING: Can't update remote HIGHESTMODSEQ for $MAILBOX");
                 $DBH->commit();
             }
             sync_messages($IDX, $MAILBOX);
         }
     }
     # clean state!
-    if ($CONFIG{oneshot}) {
-        cleanup();
-        exit 0;
-    }
+    exit 0 unless $CONFIG{watch};
     wait_notifications(900);
 }
 
diff --git a/imapsync.1 b/imapsync.1
index f4f6965..8c22222 100644
--- a/imapsync.1
+++ b/imapsync.1
@@ -10,8 +10,7 @@ imapsync \- IMAP-to-IMAP synchronization program for QRESYNC-capable servers
 .SH DESCRIPTION
 .PP
 .B imapsync\fR performs stateful synchronization between two IMAP4rev1
-servers, then (unless the flag \fB\-\-oneshot\fR is set) keeps both
-connection open and wait for new changes to arrive.
+servers.
 Such synchronization is made possible by the QRESYNC extension from
 [RFC7162]; for convenience reasons support for LIST\-EXTENDED [RFC5258],
 LIST\-STATUS [RFC5819] and UIDPLUS [RFC4315] is also required.
@@ -77,15 +76,6 @@ providing extra arguments limits the synchronization to the given
 \fIMAILBOX\fRes only.
 
 .PP
-In its default mode (unless the flag \fB\-\-oneshot\fR or
-\fB\-\-repair\fR is set), \fBimapsync\fR does not exit once all
-mailboxes have been synchronized.  Instead, it keeps both connection
-open and uses the NOTIFY command from [RFC5465] to be notified of new
-changes (on any mailbox) as soon as they arrive.  If no update is sent
-in 15 minutes, a NOOP command is issued in order not to trigger the
-servers' inactivity timeout and be logged out.
-
-.PP
 If the synchronization was interrupted during a previous run while some
 messages were being replicated (but before the UIDNEXT or HIGHESTMODSEQ
 values have been updated), \fBimapsync\fR performs a \(lqfull
@@ -104,13 +94,6 @@ Specify an alternate configuration file.  Relative paths start from
 environment variable is unset.
 
 .TP
-.B \-1\fR, \fB\-\-oneshot\fR
-Exit as soon as all mailboxes are synchronized, instead of passively
-waiting for updates from the open connections.
-Using \fB\-\-oneshot\fR removes the requirement that IMAP servers must
-advertise support the NOTIFY extension [RFC5465].
-
-.TP
 .B \-\-repair
 List the database anomalies and try to repair them.
 This is done by performing a so\-called \(lqfull synchronization\(rq,
diff --git a/imapsync.service b/imapsync.service
index e3a47e4..af63425 100644
--- a/imapsync.service
+++ b/imapsync.service
@@ -6,4 +6,4 @@ After=network.target
 ExecStart=/usr/bin/imapsync
 
 [Install]
-WantedBy=multi-user.target
+WantedBy=default.target
diff --git a/lib/Net/IMAP/Sync.pm b/lib/Net/IMAP/Sync.pm
index 26303a6..3216483 100644
--- a/lib/Net/IMAP/Sync.pm
+++ b/lib/Net/IMAP/Sync.pm
@@ -657,12 +657,12 @@ sub append($$@) {
     my @uids;
     foreach (split /,/, $uidset) {
         if (/\A([0-9]+)\z/) {
-            $UIDNEXT = $1 + 1 if $UIDNEXT <= $1;
+            $UIDNEXT = $1 + 1 if defined $UIDNEXT and $UIDNEXT <= $1;
             push @uids, $1;
         } elsif (/\A([0-9]+):([0-9]+)\z/) {
             my ($min, $max) = $1 <= $2 ? ($1,$2) : ($2,$1);
             push @uids, ($min .. $max);
-            $UIDNEXT = $max + 1 if $UIDNEXT <= $max;
+            $UIDNEXT = $max + 1 if defined $UIDNEXT and $UIDNEXT <= $max;
         } else {
             $self->panic($_);
         }
@@ -736,7 +736,6 @@ sub slurp($) {
         # select(2) to block/timeout due to the raw socket not being
         # ready.
         unless (ref $stdout eq 'IO::Socket::SSL' and $stdout->pending() > 0) {
-            my $sel = IO::Select::->new($stdout);
             my ($ok) = $self->{_SEL_OUT}->can_read(0);
             return $read unless defined $ok;
         }