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#!/usr/bin/perl |
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|
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use Coro; |
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use Coro::Handle; |
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use Coro::Event; |
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use Coro::Semaphore; |
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use Coro::Channel; |
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use Coro::Signal; |
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use Coro::RWLock; |
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|
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use Set::Scalar; |
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|
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use Fcntl; |
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|
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our $VERSION = 0.1; |
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|
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our $NOW = time; |
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|
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require "config.pl"; |
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|
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use folder; |
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use vc; |
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|
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$v = $VERBOSE; |
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|
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# WARNING: |
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# Content-Length headers are deliberately being ignored. They |
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# are broken by design and will never be supported |
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|
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# TODO: real message-id parsing |
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|
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$|=1; |
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|
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my $ecnt; |
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|
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sub slog { |
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if ($_[0] <= $v) { |
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print STDERR "[$SLAVE] ", $_[1]; |
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} |
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} |
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|
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$lockdisk = new Coro::Semaphore; |
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|
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# give up a/the timeslice |
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sub give { |
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Coro::Event::do_timer(after => 0); |
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} |
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|
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my $quit = new Coro::RWLock; |
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|
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sub rwlock::DESTROY { |
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$quit->unlock; |
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} |
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|
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sub quit_guard { |
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$quit->rdlock; |
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bless [], rwlock; |
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} |
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|
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sub find_folders { |
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my @folders; |
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|
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opendir my $dh, $PREFIX |
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or die "$PREFIX: $!"; |
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|
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while (defined (my $folder = readdir $dh)) { |
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next if $folder =~ /^\./; |
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next if $folder =~ /~$/; |
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next unless -f "$PREFIX/$folder"; |
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push @folders, $folder; |
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} |
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|
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@folders; |
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} |
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|
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my $sync_folder = new Coro::Semaphore 3; # max 3 folders in parallel |
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|
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sub sync_offer { |
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my ($folder, $avc, $diff) = @_; |
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|
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my $vc = create vc pri => 1; |
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$avc->snd("offer", $vc->{port}); |
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|
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async { |
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$vc->rcv; # need to synchronize, argl. should open on other side |
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$vc->snd(join "\0", @$diff); |
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my %dup; @dup{split /\0/, $vc->rcv} = (); |
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|
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for (@$diff) { |
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$vc->snd($folder->fetch($_)) unless exists $dup{$_}; |
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} |
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|
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defined $vc->rcv and die "protocol error, expected close"; |
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}; |
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} |
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|
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sub sync_folder { |
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my $name = $_[0]; |
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|
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my $quit_guard = quit_guard; |
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async { |
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my $guard = $sync_folder->guard; |
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my $vc = create vc; |
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|
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my $folder = new folder name => $name; |
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|
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$vc->snd("open", $name); |
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$folder->read_mdif; |
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|
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my $ctime = $folder->{host}{$OTHERNAME} || -1; |
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|
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$vc->snd("diff", $ctime); |
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|
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my %diff; # |
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# 00 - local del |
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# 01 - local add |
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# 10 - remote del |
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# 11 - remote add |
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|
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my @diff = grep { $_->[0] > $ctime } @{$folder->{diff}}; |
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|
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$diff = $vc->rcv; |
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while () { |
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if ($diff >= 0 and (!@diff or $diff < $diff[0][0])) { |
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$diff{$_} = 0b01 for split /\0/, $vc->rcv; # add |
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$diff{$_} = 0b00 for split /\0/, $vc->rcv; # del |
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|
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$diff = $vc->rcv; |
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} elsif (@diff) { |
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$diff{$_} = 0b11 for @{$diff[0][1]}; |
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$diff{$_} = 0b10 for @{$diff[0][2]}; |
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|
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shift @diff; |
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} else { |
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last; |
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} |
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} |
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|
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# append or update, depending on wether there are messages to be deleted |
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$vc->snd("begin"); |
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$folder->begin_update; |
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|
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while (my ($k,$v) = each %diff) { |
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push @{$diff[$v]}, $k; |
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slog 0, "DIFF $k : $v\n";#d# |
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} |
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|
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$vc->snd("delete", join "\0", @{$diff[2]}); |
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$folder->delete(@{$diff[0]}); |
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|
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# offer ours |
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my $offer_coro = sync_offer($folder, $vc, $diff[3]); |
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|
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# request theirs |
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{ |
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my @send = grep { !$folder->exists($_) } @{$diff[1]}; |
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$vc->snd("send", join "\0", @send); |
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$folder->append($_, $vc->rcv) for @send; |
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$vc->snd("-"); # sync |
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} |
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|
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slog 0, "waiting...\n";#d# |
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$offer_coro->join; |
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|
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# sanity check |
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$vc->snd("inventory"); |
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if ($folder->inventory ne $vc->rcv) { |
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$folder->write_mdif; |
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slog 0, "FATAL: folder inventory mismatch after update\n"; |
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} |
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|
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$vc->snd("end"); |
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$folder->end_update; |
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|
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$vc->snd("setctime", $folder->{ctime}); |
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|
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$vc->snd("mtime"); |
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$folder->{host}{$OTHERNAME} = $vc->rcv; |
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|
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$vc->snd("close"); |
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$folder->close; |
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|
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undef $quit_guard; |
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} |
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} |
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|
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sub main { |
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my $vc = create vc; |
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|
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# time checking done symmetrically |
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{ |
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my $time = time; |
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$vc->snd("time"); |
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my $othertime = $vc->rcv; |
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abs (($time + time)*0.5 - $othertime) <= $::MAXTIMEDIFF |
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or die "ERROR: time difference between hosts larger than $::MAXTIMEDIFF"; |
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} |
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|
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$vc->snd("setname", $MYNAME); $OTHERNAME = $vc->rcv; |
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|
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if ($SLAVE) { |
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# |
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} else { |
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$vc->snd("list"); |
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for (split /\0/, $vc->rcv) { |
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if (!-e "$PREFIX/$_") { |
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slog 2, "created new empty folder $_\n"; |
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sysopen my $fh, "$PREFIX/$_", O_RDWR|O_CREAT, 0666; |
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} |
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} |
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|
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for my $folder (find_folders) { |
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sync_folder $folder; |
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} |
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|
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$quit->wrlock; |
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|
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vc::snd_quit; |
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} |
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} |
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|
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sub serve_folder { |
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my $vc = shift; |
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my $name = $vc->rcv; |
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my $folder = new folder name => $name; |
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|
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slog 8, "serving folder $name\n"; |
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|
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$folder->read_mdif; |
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|
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while (my $msg = $vc->rcv) { |
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if ($msg eq "mtime") { |
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$vc->snd($folder->{mtime}); |
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} elsif ($msg eq "inventory") { |
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$vc->snd($folder->inventory); |
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} elsif ($msg eq "diff") { |
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my $time = $vc->rcv; |
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for (@{$folder->{diff}}) { |
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next if $_->[0] <= $time; |
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$vc->snd($_->[0], |
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(join "\0", @{$_->[1]}), |
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(join "\0", @{$_->[2]}), |
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); |
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} |
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$vc->snd(-1); |
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} elsif ($msg eq "begin") { |
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$folder->begin_update; |
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} elsif ($msg eq "delete") { |
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$folder->delete(split /\0/, $vc->rcv); |
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} elsif ($msg eq "offer") { |
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my $ovc = catch vc port => $vc->rcv; |
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async { |
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my @offer; |
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{ |
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my @dup; |
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|
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$ovc->snd("-"); # synchronize |
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for (split /\0/, $ovc->rcv) { |
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if ($folder->exists($_)) { |
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push @dup, $_; |
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} else { |
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push @offer, $_; |
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} |
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} |
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|
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$ovc->snd(join "\0", @dup); |
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} |
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|
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# now we'll get everything in @offer, in order |
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$folder->append($_, $ovc->rcv) for @offer; |
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$ovc->close; |
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}; |
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} elsif ($msg eq "send") { |
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$vc->pri(1); |
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$vc->snd($folder->fetch($_)) for split /\0/, $vc->rcv; |
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$vc->rcv; # sync |
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$vc->pri(0); |
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} elsif ($msg eq "end") { |
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$folder->end_update; |
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} elsif ($msg eq "mtime") { |
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$vc->snd($folder->{mtime}); |
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} elsif ($msg eq "setctime") { |
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$folder->{host}{$OTHERNAME} = $vc->rcv; |
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} elsif ($msg eq "close") { |
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$folder->close; |
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} else { |
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die "protocol error, unknown folder command ($msg)\n"; |
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} |
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} |
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} |
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|
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sub serve { |
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my $vc = shift; |
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|
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slog 8, "new connection $vc->{port}\n"; |
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|
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while (my $msg = $vc->rcv) { |
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if ($msg eq "setname") { |
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$vc->snd($MYNAME); |
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$OTHERNAME = $vc->rcv; |
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} elsif ($msg eq "pri") { |
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$vc->{pri} = $vc->rcv; |
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} elsif ($msg eq "time") { |
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$vc->snd(time); |
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} elsif ($msg eq "list") { |
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$vc->snd(join "\0", find_folders); |
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} elsif ($msg eq "open") { |
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serve_folder($vc); |
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} else { |
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die "protocol error, unknown command ($msg)\n"; |
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} |
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} |
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} |
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|
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if ($SLAVE) { |
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$HOSTID = "slave"; |
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async \&main; |
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vc::multiplex unblock \*STDIN, $SLAVE; |
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} else { |
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$HOSTID = "master"; |
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{ |
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use Socket; |
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socketpair S1, S2, AF_UNIX, SOCK_STREAM, PF_UNSPEC; |
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if (fork == 0) { |
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close S1; |
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open STDIN, "<&S2" or die; |
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open STDOUT, ">&S2" or die; |
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exec $0, "--slave"; |
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exit 255; |
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} |
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close S2; |
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async \&main; |
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vc::multiplex unblock \*S1, $SLAVE; |
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} |
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} |
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|