ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/AnyEvent/lib/AnyEvent.pm
(Generate patch)

Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.183 by root, Wed Oct 1 07:40:39 2008 UTC vs.
Revision 1.198 by root, Thu Mar 26 20:17:44 2009 UTC

… …
136 136
137These watchers are normal Perl objects with normal Perl lifetime. After 137These watchers are normal Perl objects with normal Perl lifetime. After
138creating a watcher it will immediately "watch" for events and invoke the 138creating a watcher it will immediately "watch" for events and invoke the
139callback when the event occurs (of course, only when the event model 139callback when the event occurs (of course, only when the event model
140is in control). 140is in control).
141
142Note that B<callbacks must not permanently change global variables>
143potentially in use by the event loop (such as C<$_> or C<$[>) and that B<<
144callbacks must not C<die> >>. The former is good programming practise in
145Perl and the latter stems from the fact that exception handling differs
146widely between event loops.
141 147
142To disable the watcher you have to destroy it (e.g. by setting the 148To disable the watcher you have to destroy it (e.g. by setting the
143variable you store it in to C<undef> or otherwise deleting all references 149variable you store it in to C<undef> or otherwise deleting all references
144to it). 150to it).
145 151
… …
825=item L<AnyEvent::IGS> 831=item L<AnyEvent::IGS>
826 832
827A non-blocking interface to the Internet Go Server protocol (used by 833A non-blocking interface to the Internet Go Server protocol (used by
828L<App::IGS>). 834L<App::IGS>).
829 835
830=item L<Net::IRC3> 836=item L<AnyEvent::IRC>
831 837
832AnyEvent based IRC client module family. 838AnyEvent based IRC client module family (replacing the older Net::IRC3).
833 839
834=item L<Net::XMPP2> 840=item L<Net::XMPP2>
835 841
836AnyEvent based XMPP (Jabber protocol) module family. 842AnyEvent based XMPP (Jabber protocol) module family.
837 843
… …
861no warnings; 867no warnings;
862use strict qw(vars subs); 868use strict qw(vars subs);
863 869
864use Carp; 870use Carp;
865 871
866our $VERSION = 4.3; 872our $VERSION = 4.341;
867our $MODEL; 873our $MODEL;
868 874
869our $AUTOLOAD; 875our $AUTOLOAD;
870our @ISA; 876our @ISA;
871 877
… …
1004# to support binding more than one watcher per filehandle (they usually 1010# to support binding more than one watcher per filehandle (they usually
1005# allow only one watcher per fd, so we dup it to get a different one). 1011# allow only one watcher per fd, so we dup it to get a different one).
1006sub _dupfh($$$$) { 1012sub _dupfh($$$$) {
1007 my ($poll, $fh, $r, $w) = @_; 1013 my ($poll, $fh, $r, $w) = @_;
1008 1014
1009 require Fcntl;
1010
1011 # cygwin requires the fh mode to be matching, unix doesn't 1015 # cygwin requires the fh mode to be matching, unix doesn't
1012 my ($rw, $mode) = $poll eq "r" ? ($r, "<") 1016 my ($rw, $mode) = $poll eq "r" ? ($r, "<")
1013 : $poll eq "w" ? ($w, ">") 1017 : $poll eq "w" ? ($w, ">")
1014 : Carp::croak "AnyEvent->io requires poll set to either 'r' or 'w'"; 1018 : Carp::croak "AnyEvent->io requires poll set to either 'r' or 'w'";
1015 1019
… …
1043 bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, AnyEvent::CondVar:: 1047 bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, AnyEvent::CondVar::
1044} 1048}
1045 1049
1046# default implementation for ->signal 1050# default implementation for ->signal
1047 1051
1048our %SIG_CB; 1052our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);
1053
1054sub _signal_exec {
1055 sysread $SIGPIPE_R, my $dummy, 4;
1056
1057 while (%SIG_EV) {
1058 for (keys %SIG_EV) {
1059 delete $SIG_EV{$_};
1060 $_->() for values %{ $SIG_CB{$_} || {} };
1061 }
1062 }
1063}
1049 1064
1050sub signal { 1065sub signal {
1051 my (undef, %arg) = @_; 1066 my (undef, %arg) = @_;
1052 1067
1068 unless ($SIGPIPE_R) {
1069 if (AnyEvent::WIN32) {
1070 ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
1071 AnyEvent::Util::fh_nonblocking ($SIGPIPE_R) if $SIGPIPE_R;
1072 AnyEvent::Util::fh_nonblocking ($SIGPIPE_W) if $SIGPIPE_W; # just in case
1073 } else {
1074 pipe $SIGPIPE_R, $SIGPIPE_W;
1075 require Fcntl;
1076 fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R;
1077 fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case
1078 }
1079
1080 $SIGPIPE_R
1081 or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
1082
1083 $SIG_IO = AnyEvent->io (fh => $SIGPIPE_R, poll => "r", cb => \&_signal_exec);
1084 }
1085
1053 my $signal = uc $arg{signal} 1086 my $signal = uc $arg{signal}
1054 or Carp::croak "required option 'signal' is missing"; 1087 or Carp::croak "required option 'signal' is missing";
1055 1088
1056 $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; 1089 $SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1057 $SIG{$signal} ||= sub { 1090 $SIG{$signal} ||= sub {
1058 $_->() for values %{ $SIG_CB{$signal} || {} }; 1091 syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
1092 undef $SIG_EV{$signal};
1059 }; 1093 };
1060 1094
1061 bless [$signal, $arg{cb}], "AnyEvent::Base::Signal" 1095 bless [$signal, $arg{cb}], "AnyEvent::Base::Signal"
1062} 1096}
1063 1097
… …
1263used, and preference will be given to protocols mentioned earlier in the 1297used, and preference will be given to protocols mentioned earlier in the
1264list. 1298list.
1265 1299
1266This variable can effectively be used for denial-of-service attacks 1300This variable can effectively be used for denial-of-service attacks
1267against local programs (e.g. when setuid), although the impact is likely 1301against local programs (e.g. when setuid), although the impact is likely
1268small, as the program has to handle connection errors already- 1302small, as the program has to handle conenction and other failures anyways.
1269 1303
1270Examples: C<PERL_ANYEVENT_PROTOCOLS=ipv4,ipv6> - prefer IPv4 over IPv6, 1304Examples: C<PERL_ANYEVENT_PROTOCOLS=ipv4,ipv6> - prefer IPv4 over IPv6,
1271but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4> 1305but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4>
1272- only support IPv4, never try to resolve or contact IPv6 1306- only support IPv4, never try to resolve or contact IPv6
1273addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or 1307addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or
… …
1533watcher. 1567watcher.
1534 1568
1535=head3 Results 1569=head3 Results
1536 1570
1537 name watchers bytes create invoke destroy comment 1571 name watchers bytes create invoke destroy comment
1538 EV/EV 400000 244 0.56 0.46 0.31 EV native interface 1572 EV/EV 400000 224 0.47 0.35 0.27 EV native interface
1539 EV/Any 100000 244 2.50 0.46 0.29 EV + AnyEvent watchers 1573 EV/Any 100000 224 2.88 0.34 0.27 EV + AnyEvent watchers
1540 CoroEV/Any 100000 244 2.49 0.44 0.29 coroutines + Coro::Signal 1574 CoroEV/Any 100000 224 2.85 0.35 0.28 coroutines + Coro::Signal
1541 Perl/Any 100000 513 4.92 0.87 1.12 pure perl implementation 1575 Perl/Any 100000 452 4.13 0.73 0.95 pure perl implementation
1542 Event/Event 16000 516 31.88 31.30 0.85 Event native interface 1576 Event/Event 16000 517 32.20 31.80 0.81 Event native interface
1543 Event/Any 16000 590 35.75 31.42 1.08 Event + AnyEvent watchers 1577 Event/Any 16000 590 35.85 31.55 1.06 Event + AnyEvent watchers
1544 Glib/Any 16000 1357 98.22 12.41 54.00 quadratic behaviour 1578 Glib/Any 16000 1357 102.33 12.31 51.00 quadratic behaviour
1545 Tk/Any 2000 1860 26.97 67.98 14.00 SEGV with >> 2000 watchers 1579 Tk/Any 2000 1860 27.20 66.31 14.00 SEGV with >> 2000 watchers
1546 POE/Event 2000 6644 108.64 736.02 14.73 via POE::Loop::Event 1580 POE/Event 2000 6328 109.99 751.67 14.02 via POE::Loop::Event
1547 POE/Select 2000 6343 94.13 809.12 565.96 via POE::Loop::Select 1581 POE/Select 2000 6027 94.54 809.13 579.80 via POE::Loop::Select
1548 1582
1549=head3 Discussion 1583=head3 Discussion
1550 1584
1551The benchmark does I<not> measure scalability of the event loop very 1585The benchmark does I<not> measure scalability of the event loop very
1552well. For example, a select-based event loop (such as the pure perl one) 1586well. For example, a select-based event loop (such as the pure perl one)
… …
1754watchers, as the management overhead dominates. 1788watchers, as the management overhead dominates.
1755 1789
1756=back 1790=back
1757 1791
1758 1792
1793=head1 SIGNALS
1794
1795AnyEvent currently installs handlers for these signals:
1796
1797=over 4
1798
1799=item SIGCHLD
1800
1801A handler for C<SIGCHLD> is installed by AnyEvent's child watcher
1802emulation for event loops that do not support them natively. Also, some
1803event loops install a similar handler.
1804
1805=item SIGPIPE
1806
1807A no-op handler is installed for C<SIGPIPE> when C<$SIG{PIPE}> is C<undef>
1808when AnyEvent gets loaded.
1809
1810The rationale for this is that AnyEvent users usually do not really depend
1811on SIGPIPE delivery (which is purely an optimisation for shell use, or
1812badly-written programs), but C<SIGPIPE> can cause spurious and rare
1813program exits as a lot of people do not expect C<SIGPIPE> when writing to
1814some random socket.
1815
1816The rationale for installing a no-op handler as opposed to ignoring it is
1817that this way, the handler will be restored to defaults on exec.
1818
1819Feel free to install your own handler, or reset it to defaults.
1820
1821=back
1822
1823=cut
1824
1825$SIG{PIPE} = sub { }
1826 unless defined $SIG{PIPE};
1827
1828
1759=head1 FORK 1829=head1 FORK
1760 1830
1761Most event libraries are not fork-safe. The ones who are usually are 1831Most event libraries are not fork-safe. The ones who are usually are
1762because they rely on inefficient but fork-safe C<select> or C<poll> 1832because they rely on inefficient but fork-safe C<select> or C<poll>
1763calls. Only L<EV> is fully fork-aware. 1833calls. Only L<EV> is fully fork-aware.
… …
1791=head1 BUGS 1861=head1 BUGS
1792 1862
1793Perl 5.8 has numerous memleaks that sometimes hit this module and are hard 1863Perl 5.8 has numerous memleaks that sometimes hit this module and are hard
1794to work around. If you suffer from memleaks, first upgrade to Perl 5.10 1864to work around. If you suffer from memleaks, first upgrade to Perl 5.10
1795and check wether the leaks still show up. (Perl 5.10.0 has other annoying 1865and check wether the leaks still show up. (Perl 5.10.0 has other annoying
1796mamleaks, such as leaking on C<map> and C<grep> but it is usually not as 1866memleaks, such as leaking on C<map> and C<grep> but it is usually not as
1797pronounced). 1867pronounced).
1798 1868
1799 1869
1800=head1 SEE ALSO 1870=head1 SEE ALSO
1801 1871

Diff Legend

– Removed lines
+ Added lines
< Changed lines
> Changed lines