[ViewVC] Annotation of: cvs/syncmail/syncmail

#!/usr/bin/perl

use Coro;
use Coro::Handle;
use Coro::Event;
use Coro::Semaphore;
use Coro::Channel;
use Coro::Signal;
use Coro::RWLock;

use Set::Scalar;

use Fcntl;

our $VERSION = 0.1;

our $NOW = time;

require "config.pl";

use folder;
use vc;

$v = $VERBOSE;

# WARNING:
# Content-Length headers are deliberately being ignored. They
# are broken by design and will never be supported

# TODO: real message-id parsing

$|=1;

my $ecnt;

sub slog {
   if ($_[0] <= $v) {
      print STDERR "[$SLAVE] ", $_[1];
   }
}

$lockdisk = new Coro::Semaphore;

# give up a/the timeslice
sub give {
   Coro::Event::do_timer(after => 0);
}

my $quit = new Coro::RWLock;

sub rwlock::DESTROY {
   $quit->unlock;
}

sub quit_guard {
   $quit->rdlock;
   bless [], rwlock;
}

sub find_folders {
   my @folders;

   opendir my $dh, $PREFIX
      or die "$PREFIX: $!";

   while (defined (my $folder = readdir $dh)) {
      next if $folder =~ /^\./;
      next if $folder =~ /~$/;
      next unless -f "$PREFIX/$folder";
      push @folders, $folder;
   }

   @folders;
}

my $sync_folder = new Coro::Semaphore 3; # max 3 folders in parallel

sub sync_offer {
   my ($folder, $avc, $diff) = @_;

   my $vc = create vc pri => 1;
   $avc->snd("offer", $vc->{port});

   async {
      $vc->rcv; # need to synchronize, argl. should open on other side
      $vc->snd(join "\0", @$diff);
      my %dup; @dup{split /\0/, $vc->rcv} = ();

      for (@$diff) {
         $vc->snd($folder->fetch($_)) unless exists $dup{$_};
      }

      defined $vc->rcv and die "protocol error, expected close";
   };
}

sub sync_folder {
   my $name = $_[0];

   my $quit_guard = quit_guard;
   async {
      my $guard = $sync_folder->guard;
      my $vc = create vc;

      my $folder = new folder name => $name;

      $vc->snd("open", $name);
      $folder->read_mdif;

      my $ctime = $folder->{host}{$OTHERNAME} || -1;

      $vc->snd("diff", $ctime);

      my %diff; #
      # 00 - local del
      # 01 - local add
      # 10 - remote del
      # 11 - remote add

      my @diff = grep { $_->[0] > $ctime } @{$folder->{diff}};

      $diff = $vc->rcv;
      while () {
         if ($diff >= 0 and (!@diff or $diff < $diff[0][0])) {
            $diff{$_} = 0b01 for split /\0/, $vc->rcv; # add
            $diff{$_} = 0b00 for split /\0/, $vc->rcv; # del

            $diff = $vc->rcv;
         } elsif (@diff) {
            $diff{$_} = 0b11 for @{$diff[0][1]};
            $diff{$_} = 0b10 for @{$diff[0][2]};

            shift @diff;
         } else {
            last;
         }
      }

      # append or update, depending on wether there are messages to be deleted
      $vc->snd("begin");
      $folder->begin_update;

      while (my ($k,$v) = each %diff) {
         push @{$diff[$v]}, $k;
         slog 0, "DIFF $k : $v\n";#d#
      }

      $vc->snd("delete", join "\0", @{$diff[2]});
      $folder->delete(@{$diff[0]});

      # offer ours
      my $offer_coro = sync_offer($folder, $vc, $diff[3]);

      # request theirs
      {
         my @send = grep { !$folder->exists($_) } @{$diff[1]};
         $vc->snd("send", join "\0", @send);
         $folder->append($_, $vc->rcv) for @send;
         $vc->snd("-"); # sync
      }

      slog 0, "waiting...\n";#d#
      $offer_coro->join;

      # sanity check
      $vc->snd("inventory");
      if ($folder->inventory ne $vc->rcv) {
         $folder->write_mdif;
         slog 0, "FATAL: folder inventory mismatch after update\n";
      }

      $vc->snd("end");
      $folder->end_update;
      
      $vc->snd("setctime", $folder->{ctime});

      $vc->snd("mtime");
      $folder->{host}{$OTHERNAME} = $vc->rcv;

      $vc->snd("close");
      $folder->close;

      undef $quit_guard;
   }
}

sub main {
   my $vc = create vc;

   # time checking done symmetrically
   {
      my $time = time;
      $vc->snd("time");
      my $othertime = $vc->rcv;
      abs (($time + time)*0.5 - $othertime) <= $::MAXTIMEDIFF
         or die "ERROR: time difference between hosts larger than $::MAXTIMEDIFF";
   }

   $vc->snd("setname", $MYNAME); $OTHERNAME = $vc->rcv;

   if ($SLAVE) {
      #
   } else {
      $vc->snd("list");
      for (split /\0/, $vc->rcv) {
         if (!-e "$PREFIX/$_") {
            slog 2, "created new empty folder $_\n";
            sysopen my $fh, "$PREFIX/$_", O_RDWR|O_CREAT, 0666;
         }
      }

      for my $folder (find_folders) {
         sync_folder $folder;
      }

      $quit->wrlock;

      vc::snd_quit;
   }
}

sub serve_folder {
   my $vc = shift;
   my $name = $vc->rcv;
   my $folder = new folder name => $name;

   slog 8, "serving folder $name\n";

   $folder->read_mdif;

   while (my $msg = $vc->rcv) {
      if ($msg eq "mtime") {
         $vc->snd($folder->{mtime});
      } elsif ($msg eq "inventory") {
         $vc->snd($folder->inventory);
      } elsif ($msg eq "diff") {
         my $time = $vc->rcv;
         for (@{$folder->{diff}}) {
            next if $_->[0] <= $time;
            $vc->snd($_->[0],
                     (join "\0", @{$_->[1]}),
                     (join "\0", @{$_->[2]}),
                    );
         }
         $vc->snd(-1);
      } elsif ($msg eq "begin") {
         $folder->begin_update;
      } elsif ($msg eq "delete") {
         $folder->delete(split /\0/, $vc->rcv);
      } elsif ($msg eq "offer") {
         my $ovc = catch vc port => $vc->rcv;
         async {
            my @offer;
            {
               my @dup;

               $ovc->snd("-"); # synchronize
               for (split /\0/, $ovc->rcv) {
                  if ($folder->exists($_)) {
                     push @dup, $_;
                  } else {
                     push @offer, $_;
                  }
               }

               $ovc->snd(join "\0", @dup);
            }

            # now we'll get everything in @offer, in order
            $folder->append($_, $ovc->rcv) for @offer;
            $ovc->close;
         };
      } elsif ($msg eq "send") {
         $vc->pri(1);
         $vc->snd($folder->fetch($_)) for split /\0/, $vc->rcv;
         $vc->rcv; # sync
         $vc->pri(0);
      } elsif ($msg eq "end") {
         $folder->end_update;
      } elsif ($msg eq "mtime") {
         $vc->snd($folder->{mtime});
      } elsif ($msg eq "setctime") {
         $folder->{host}{$OTHERNAME} = $vc->rcv;
      } elsif ($msg eq "close") {
         $folder->close;
      } else {
         die "protocol error, unknown folder command ($msg)\n";
      }
   }
}

sub serve {
   my $vc = shift;

   slog 8, "new connection $vc->{port}\n";

   while (my $msg = $vc->rcv) {
      if ($msg eq "setname") {
         $vc->snd($MYNAME);
         $OTHERNAME = $vc->rcv;
      } elsif ($msg eq "pri") {
         $vc->{pri} = $vc->rcv;
      } elsif ($msg eq "time") {
         $vc->snd(time);
      } elsif ($msg eq "list") {
         $vc->snd(join "\0", find_folders);
      } elsif ($msg eq "open") {
         serve_folder($vc);
      } else {
         die "protocol error, unknown command ($msg)\n";
      }
   }
}

if ($SLAVE) {
   $HOSTID = "slave";
   async \&main;
   vc::multiplex unblock \*STDIN, $SLAVE;
} else {
   $HOSTID = "master";
   {
      use Socket;
      socketpair S1, S2, AF_UNIX, SOCK_STREAM, PF_UNSPEC;
      if (fork == 0) {
         close S1;
         open STDIN, "<&S2" or die;
         open STDOUT, ">&S2" or die;
         exec $0, "--slave";
         exit 255;
      }
      close S2;
      async \&main;
      vc::multiplex unblock \*S1, $SLAVE;
   }
}

Revision:	1.8
Committed:	Mon Oct 29 02:36:32 2001 UTC (22 years, 6 months ago) by root
Branch:	MAIN
CVS Tags:	HEAD
Changes since 1.7:	+0 -3 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	#!/usr/bin/perl
2
3			use Coro;
4			use Coro::Handle;
5			use Coro::Event;
6			use Coro::Semaphore;
7			use Coro::Channel;
8			use Coro::Signal;
9	root	1.2	use Coro::RWLock;
10	root	1.1
11	root	1.4	use Set::Scalar;
12
13	root	1.2	use Fcntl;
14	root	1.1
15	root	1.6	our $VERSION = 0.1;
16	root	1.2
17	root	1.6	our $NOW = time;
18	root	1.2
19	root	1.3	require "config.pl";
20
21			use folder;
22			use vc;
23
24			$v = $VERBOSE;
25	root	1.2
26			# WARNING:
27			# Content-Length headers are deliberately being ignored. They
28			# are broken by design and will never be supported
29	root	1.1
30			# TODO: real message-id parsing
31
32			$\|=1;
33
34			my $ecnt;
35
36			sub slog {
37			if ($_[0] <= $v) {
38	root	1.2	print STDERR "[$SLAVE] ", $_[1];
39	root	1.1	}
40			}
41
42	root	1.3	$lockdisk = new Coro::Semaphore;
43	root	1.2
44			# give up a/the timeslice
45			sub give {
46			Coro::Event::do_timer(after => 0);
47			}
48
49			my $quit = new Coro::RWLock;
50
51			sub rwlock::DESTROY {
52			$quit->unlock;
53			}
54
55			sub quit_guard {
56			$quit->rdlock;
57			bless [], rwlock;
58			}
59
60			sub find_folders {
61			my @folders;
62
63			opendir my $dh, $PREFIX
64			or die "$PREFIX: $!";
65
66			while (defined (my $folder = readdir $dh)) {
67			next if $folder =~ /^\./;
68	root	1.6	next if $folder =~ /~$/;
69	root	1.2	next unless -f "$PREFIX/$folder";
70			push @folders, $folder;
71			}
72
73			@folders;
74			}
75
76			my $sync_folder = new Coro::Semaphore 3; # max 3 folders in parallel
77
78	root	1.7	sub sync_offer {
79			my ($folder, $avc, $diff) = @_;
80
81			my $vc = create vc pri => 1;
82			$avc->snd("offer", $vc->{port});
83
84			async {
85			$vc->rcv; # need to synchronize, argl. should open on other side
86			$vc->snd(join "\0", @$diff);
87			my %dup; @dup{split /\0/, $vc->rcv} = ();
88
89			for (@$diff) {
90			$vc->snd($folder->fetch($_)) unless exists $dup{$_};
91			}
92
93			defined $vc->rcv and die "protocol error, expected close";
94			};
95			}
96
97	root	1.2	sub sync_folder {
98			my $name = $_[0];
99
100			my $quit_guard = quit_guard;
101			async {
102			my $guard = $sync_folder->guard;
103	root	1.6	my $vc = create vc;
104	root	1.2
105	root	1.3	my $folder = new folder name => $name;
106	root	1.2
107	root	1.3	$vc->snd("open", $name);
108	root	1.2	$folder->read_mdif;
109	root	1.3
110	root	1.4	my $ctime = $folder->{host}{$OTHERNAME} \|\| -1;
111	root	1.1
112	root	1.4	$vc->snd("diff", $ctime);
113
114	root	1.6	my %diff; #
115			# 00 - local del
116			# 01 - local add
117			# 10 - remote del
118			# 11 - remote add
119	root	1.4
120			my @diff = grep { $_->[0] > $ctime } @{$folder->{diff}};
121	root	1.7
122	root	1.4	$diff = $vc->rcv;
123			while () {
124	root	1.7	if ($diff >= 0 and (!@diff or $diff < $diff[0][0])) {
125	root	1.6	$diff{$_} = 0b01 for split /\0/, $vc->rcv; # add
126			$diff{$_} = 0b00 for split /\0/, $vc->rcv; # del
127
128	root	1.4	$diff = $vc->rcv;
129			} elsif (@diff) {
130	root	1.6	$diff{$_} = 0b11 for @{$diff[0][1]};
131			$diff{$_} = 0b10 for @{$diff[0][2]};
132
133	root	1.4	shift @diff;
134			} else {
135			last;
136			}
137			}
138
139	root	1.6	# append or update, depending on wether there are messages to be deleted
140			$vc->snd("begin");
141			$folder->begin_update;
142
143			while (my ($k,$v) = each %diff) {
144			push @{$diff[$v]}, $k;
145			slog 0, "DIFF $k : $v\n";#d#
146			}
147
148			$vc->snd("delete", join "\0", @{$diff[2]});
149			$folder->delete(@{$diff[0]});
150
151	root	1.7	# offer ours
152			my $offer_coro = sync_offer($folder, $vc, $diff[3]);
153
154			# request theirs
155			{
156			my @send = grep { !$folder->exists($_) } @{$diff[1]};
157			$vc->snd("send", join "\0", @send);
158			$folder->append($_, $vc->rcv) for @send;
159			$vc->snd("-"); # sync
160			}
161
162			slog 0, "waiting...\n";#d#
163			$offer_coro->join;
164
165			# sanity check
166			$vc->snd("inventory");
167			if ($folder->inventory ne $vc->rcv) {
168			$folder->write_mdif;
169			slog 0, "FATAL: folder inventory mismatch after update\n";
170			}
171
172	root	1.6	$vc->snd("end");
173			$folder->end_update;
174	root	1.4
175	root	1.7	$vc->snd("setctime", $folder->{ctime});
176
177			$vc->snd("mtime");
178	root	1.6	$folder->{host}{$OTHERNAME} = $vc->rcv;
179
180	root	1.7	$vc->snd("close");
181			$folder->close;
182	root	1.1
183	root	1.2	undef $quit_guard;
184	root	1.1	}
185			}
186
187	root	1.2	sub main {
188	root	1.6	my $vc = create vc;
189	root	1.3
190	root	1.2	# time checking done symmetrically
191			{
192			my $time = time;
193	root	1.3	$vc->snd("time");
194			my $othertime = $vc->rcv;
195	root	1.2	abs (($time + time)*0.5 - $othertime) <= $::MAXTIMEDIFF
196			or die "ERROR: time difference between hosts larger than $::MAXTIMEDIFF";
197			}
198	root	1.3
199	root	1.6	$vc->snd("setname", $MYNAME); $OTHERNAME = $vc->rcv;
200	root	1.1
201	root	1.2	if ($SLAVE) {
202			#
203			} else {
204	root	1.3	$vc->snd("list");
205			for (split /\0/, $vc->rcv) {
206	root	1.2	if (!-e "$PREFIX/$_") {
207			slog 2, "created new empty folder $_\n";
208			sysopen my $fh, "$PREFIX/$_", O_RDWR\|O_CREAT, 0666;
209			}
210			}
211	root	1.1
212	root	1.2	for my $folder (find_folders) {
213			sync_folder $folder;
214	root	1.1	}
215	root	1.2
216			$quit->wrlock;
217	root	1.3
218			vc::snd_quit;
219			}
220			}
221
222			sub serve_folder {
223			my $vc = shift;
224			my $name = $vc->rcv;
225			my $folder = new folder name => $name;
226
227			slog 8, "serving folder $name\n";
228
229			$folder->read_mdif;
230
231			while (my $msg = $vc->rcv) {
232			if ($msg eq "mtime") {
233			$vc->snd($folder->{mtime});
234	root	1.6	} elsif ($msg eq "inventory") {
235			$vc->snd($folder->inventory);
236	root	1.4	} elsif ($msg eq "diff") {
237			my $time = $vc->rcv;
238			for (@{$folder->{diff}}) {
239			next if $_->[0] <= $time;
240			$vc->snd($_->[0],
241			(join "\0", @{$_->[1]}),
242			(join "\0", @{$_->[2]}),
243			);
244			}
245			$vc->snd(-1);
246	root	1.6	} elsif ($msg eq "begin") {
247			$folder->begin_update;
248	root	1.7	} elsif ($msg eq "delete") {
249			$folder->delete(split /\0/, $vc->rcv);
250			} elsif ($msg eq "offer") {
251			my $ovc = catch vc port => $vc->rcv;
252			async {
253			my @offer;
254			{
255			my @dup;
256
257			$ovc->snd("-"); # synchronize
258			for (split /\0/, $ovc->rcv) {
259			if ($folder->exists($_)) {
260			push @dup, $_;
261			} else {
262			push @offer, $_;
263			}
264			}
265
266			$ovc->snd(join "\0", @dup);
267			}
268
269			# now we'll get everything in @offer, in order
270			$folder->append($_, $ovc->rcv) for @offer;
271			$ovc->close;
272			};
273			} elsif ($msg eq "send") {
274			$vc->pri(1);
275			$vc->snd($folder->fetch($_)) for split /\0/, $vc->rcv;
276			$vc->rcv; # sync
277			$vc->pri(0);
278	root	1.6	} elsif ($msg eq "end") {
279			$folder->end_update;
280			} elsif ($msg eq "mtime") {
281			$vc->snd($folder->{mtime});
282	root	1.4	} elsif ($msg eq "setctime") {
283			$folder->{host}{$OTHERNAME} = $vc->rcv;
284	root	1.7	} elsif ($msg eq "close") {
285			$folder->close;
286	root	1.3	} else {
287			die "protocol error, unknown folder command ($msg)\n";
288			}
289			}
290			}
291
292			sub serve {
293			my $vc = shift;
294
295			slog 8, "new connection $vc->{port}\n";
296
297			while (my $msg = $vc->rcv) {
298	root	1.6	if ($msg eq "setname") {
299			$vc->snd($MYNAME);
300			$OTHERNAME = $vc->rcv;
301	root	1.3	} elsif ($msg eq "pri") {
302	root	1.6	$vc->{pri} = $vc->rcv;
303	root	1.3	} elsif ($msg eq "time") {
304			$vc->snd(time);
305			} elsif ($msg eq "list") {
306			$vc->snd(join "\0", find_folders);
307			} elsif ($msg eq "open") {
308			serve_folder($vc);
309			} else {
310			die "protocol error, unknown command ($msg)\n";
311			}
312	root	1.1	}
313			}
314
315			if ($SLAVE) {
316			$HOSTID = "slave";
317	root	1.2	async \&main;
318	root	1.3	vc::multiplex unblock \*STDIN, $SLAVE;
319	root	1.1	} else {
320			$HOSTID = "master";
321			{
322			use Socket;
323			socketpair S1, S2, AF_UNIX, SOCK_STREAM, PF_UNSPEC;
324			if (fork == 0) {
325	root	1.2	close S1;
326	root	1.1	open STDIN, "<&S2" or die;
327			open STDOUT, ">&S2" or die;
328			exec $0, "--slave";
329			exit 255;
330			}
331	root	1.2	close S2;
332			async \&main;
333	root	1.3	vc::multiplex unblock \*S1, $SLAVE;
334	root	1.1	}
335			}
336