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 1.264 by root, Wed Jul 29 12:42:09 2009 UTC vs.
Revision 1.272 by root, Thu Aug 6 13:31:01 2009 UTC

… …
181my variables are only visible after the statement in which they are 181my variables are only visible after the statement in which they are
182declared. 182declared.
183 183
184=head2 I/O WATCHERS 184=head2 I/O WATCHERS
185 185
186 $w = AnyEvent->io (
187 fh => <filehandle_or_fileno>,
188 poll => <"r" or "w">,
189 cb => <callback>,
190 );
191
186You can create an I/O watcher by calling the C<< AnyEvent->io >> method 192You can create an I/O watcher by calling the C<< AnyEvent->io >> method
187with the following mandatory key-value pairs as arguments: 193with the following mandatory key-value pairs as arguments:
188 194
189C<fh> is the Perl I<file handle> (or a naked file descriptor) to watch 195C<fh> is the Perl I<file handle> (or a naked file descriptor) to watch
190for events (AnyEvent might or might not keep a reference to this file 196for events (AnyEvent might or might not keep a reference to this file
… …
219 undef $w; 225 undef $w;
220 }); 226 });
221 227
222=head2 TIME WATCHERS 228=head2 TIME WATCHERS
223 229
230 $w = AnyEvent->timer (after => <seconds>, cb => <callback>);
231
232 $w = AnyEvent->timer (
233 after => <fractional_seconds>,
234 interval => <fractional_seconds>,
235 cb => <callback>,
236 );
237
224You can create a time watcher by calling the C<< AnyEvent->timer >> 238You can create a time watcher by calling the C<< AnyEvent->timer >>
225method with the following mandatory arguments: 239method with the following mandatory arguments:
226 240
227C<after> specifies after how many seconds (fractional values are 241C<after> specifies after how many seconds (fractional values are
228supported) the callback should be invoked. C<cb> is the callback to invoke 242supported) the callback should be invoked. C<cb> is the callback to invoke
… …
355 369
356=back 370=back
357 371
358=head2 SIGNAL WATCHERS 372=head2 SIGNAL WATCHERS
359 373
374 $w = AnyEvent->signal (signal => <uppercase_signal_name>, cb => <callback>);
375
360You can watch for signals using a signal watcher, C<signal> is the signal 376You can watch for signals using a signal watcher, C<signal> is the signal
361I<name> in uppercase and without any C<SIG> prefix, C<cb> is the Perl 377I<name> in uppercase and without any C<SIG> prefix, C<cb> is the Perl
362callback to be invoked whenever a signal occurs. 378callback to be invoked whenever a signal occurs.
363 379
364Although the callback might get passed parameters, their value and 380Although the callback might get passed parameters, their value and
… …
383 my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 }); 399 my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });
384 400
385=head3 Signal Races, Delays and Workarounds 401=head3 Signal Races, Delays and Workarounds
386 402
387Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching 403Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching
388callbacks to signals in a generic way, which is a pity, as you cannot do 404callbacks to signals in a generic way, which is a pity, as you cannot
389race-free signal handling in perl. AnyEvent will try to do it's best, but 405do race-free signal handling in perl, requiring C libraries for
406this. AnyEvent will try to do it's best, which means in some cases,
390in some cases, signals will be delayed. The maximum time a signal might 407signals will be delayed. The maximum time a signal might be delayed is
391be delayed is specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 408specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This
392seconds). This variable can be changed only before the first signal 409variable can be changed only before the first signal watcher is created,
393watcher is created, and should be left alone otherwise. Higher values 410and should be left alone otherwise. This variable determines how often
411AnyEvent polls for signals (in case a wake-up was missed). Higher values
394will cause fewer spurious wake-ups, which is better for power and CPU 412will cause fewer spurious wake-ups, which is better for power and CPU
413saving.
414
395saving. All these problems can be avoided by installing the optional 415All these problems can be avoided by installing the optional
396L<Async::Interrupt> module. This will not work with inherently broken 416L<Async::Interrupt> module, which works with most event loops. It will not
397event loops such as L<Event> or L<Event::Lib> (and not with L<POE> 417work with inherently broken event loops such as L<Event> or L<Event::Lib>
398currently, as POE does it's own workaround with one-second latency). With 418(and not with L<POE> currently, as POE does it's own workaround with
399those, you just have to suffer the delays. 419one-second latency). For those, you just have to suffer the delays.
400 420
401=head2 CHILD PROCESS WATCHERS 421=head2 CHILD PROCESS WATCHERS
422
423 $w = AnyEvent->child (pid => <process id>, cb => <callback>);
402 424
403You can also watch on a child process exit and catch its exit status. 425You can also watch on a child process exit and catch its exit status.
404 426
405The child process is specified by the C<pid> argument (one some backends, 427The child process is specified by the C<pid> argument (one some backends,
406using C<0> watches for any child process exit, on others this will 428using C<0> watches for any child process exit, on others this will
… …
455 # do something else, then wait for process exit 477 # do something else, then wait for process exit
456 $done->recv; 478 $done->recv;
457 479
458=head2 IDLE WATCHERS 480=head2 IDLE WATCHERS
459 481
482 $w = AnyEvent->idle (cb => <callback>);
483
460Sometimes there is a need to do something, but it is not so important 484Sometimes there is a need to do something, but it is not so important
461to do it instantly, but only when there is nothing better to do. This 485to do it instantly, but only when there is nothing better to do. This
462"nothing better to do" is usually defined to be "no other events need 486"nothing better to do" is usually defined to be "no other events need
463attention by the event loop". 487attention by the event loop".
464 488
… …
490 }); 514 });
491 }); 515 });
492 516
493=head2 CONDITION VARIABLES 517=head2 CONDITION VARIABLES
494 518
519 $cv = AnyEvent->condvar;
520
521 $cv->send (<list>);
522 my @res = $cv->recv;
523
495If you are familiar with some event loops you will know that all of them 524If you are familiar with some event loops you will know that all of them
496require you to run some blocking "loop", "run" or similar function that 525require you to run some blocking "loop", "run" or similar function that
497will actively watch for new events and call your callbacks. 526will actively watch for new events and call your callbacks.
498 527
499AnyEvent is slightly different: it expects somebody else to run the event 528AnyEvent is slightly different: it expects somebody else to run the event
… …
761=item $cb = $cv->cb ($cb->($cv)) 790=item $cb = $cv->cb ($cb->($cv))
762 791
763This is a mutator function that returns the callback set and optionally 792This is a mutator function that returns the callback set and optionally
764replaces it before doing so. 793replaces it before doing so.
765 794
766The callback will be called when the condition becomes "true", i.e. when 795The callback will be called when the condition becomes (or already was)
767C<send> or C<croak> are called, with the only argument being the condition 796"true", i.e. when C<send> or C<croak> are called (or were called), with
768variable itself. Calling C<recv> inside the callback or at any later time 797the only argument being the condition variable itself. Calling C<recv>
769is guaranteed not to block. 798inside the callback or at any later time is guaranteed not to block.
770 799
771=back 800=back
772 801
773=head1 SUPPORTED EVENT LOOPS/BACKENDS 802=head1 SUPPORTED EVENT LOOPS/BACKENDS
774 803
… …
1086 1115
1087BEGIN { AnyEvent::common_sense } 1116BEGIN { AnyEvent::common_sense }
1088 1117
1089use Carp (); 1118use Carp ();
1090 1119
1091our $VERSION = 4.881; 1120our $VERSION = 4.901;
1092our $MODEL; 1121our $MODEL;
1093 1122
1094our $AUTOLOAD; 1123our $AUTOLOAD;
1095our @ISA; 1124our @ISA;
1096 1125
… …
1335 undef $SIG_TW 1364 undef $SIG_TW
1336 unless --$SIG_COUNT; 1365 unless --$SIG_COUNT;
1337} 1366}
1338 1367
1339our $_sig_name_init; $_sig_name_init = sub { 1368our $_sig_name_init; $_sig_name_init = sub {
1369 eval q{ # poor man's autoloading
1340 undef $_sig_name_init; 1370 undef $_sig_name_init;
1341 1371
1342 if (_have_async_interrupt) { 1372 if (_have_async_interrupt) {
1343 *sig2num = \&Async::Interrupt::sig2num; 1373 *sig2num = \&Async::Interrupt::sig2num;
1344 *sig2name = \&Async::Interrupt::sig2name; 1374 *sig2name = \&Async::Interrupt::sig2name;
1345 } else { 1375 } else {
1346 require Config; 1376 require Config;
1347 1377
1348 my %signame2num; 1378 my %signame2num;
1349 @signame2num{ split ' ', $Config::Config{sig_name} } 1379 @signame2num{ split ' ', $Config::Config{sig_name} }
1350 = split ' ', $Config::Config{sig_num}; 1380 = split ' ', $Config::Config{sig_num};
1351 1381
1352 my @signum2name; 1382 my @signum2name;
1353 @signum2name[values %signame2num] = keys %signame2num; 1383 @signum2name[values %signame2num] = keys %signame2num;
1354 1384
1355 *sig2num = sub($) { 1385 *sig2num = sub($) {
1356 $_[0] > 0 ? shift : $signame2num{+shift} 1386 $_[0] > 0 ? shift : $signame2num{+shift}
1357 }; 1387 };
1358 *sig2name = sub ($) { 1388 *sig2name = sub ($) {
1359 $_[0] > 0 ? $signum2name[+shift] : shift 1389 $_[0] > 0 ? $signum2name[+shift] : shift
1390 };
1360 }; 1391 }
1361 } 1392 };
1393 die if $@;
1362}; 1394};
1363 1395
1364sub sig2num ($) { &$_sig_name_init; &sig2num } 1396sub sig2num ($) { &$_sig_name_init; &sig2num }
1365sub sig2name($) { &$_sig_name_init; &sig2name } 1397sub sig2name($) { &$_sig_name_init; &sig2name }
1366 1398
1367sub _signal { 1399sub signal {
1400 eval q{ # poor man's autoloading {}
1401 # probe for availability of Async::Interrupt
1402 if (_have_async_interrupt) {
1403 warn "AnyEvent: using Async::Interrupt for race-free signal handling.\n" if $VERBOSE >= 8;
1404
1405 $SIGPIPE_R = new Async::Interrupt::EventPipe;
1406 $SIG_IO = AnyEvent->io (fh => $SIGPIPE_R->fileno, poll => "r", cb => \&_signal_exec);
1407
1408 } else {
1409 warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;
1410
1411 require Fcntl;
1412
1413 if (AnyEvent::WIN32) {
1414 require AnyEvent::Util;
1415
1416 ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
1417 AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R;
1418 AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case
1419 } else {
1420 pipe $SIGPIPE_R, $SIGPIPE_W;
1421 fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R;
1422 fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case
1423
1424 # not strictly required, as $^F is normally 2, but let's make sure...
1425 fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;
1426 fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;
1427 }
1428
1429 $SIGPIPE_R
1430 or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
1431
1432 $SIG_IO = AnyEvent->io (fh => $SIGPIPE_R, poll => "r", cb => \&_signal_exec);
1433 }
1434
1435 *signal = sub {
1368 my (undef, %arg) = @_; 1436 my (undef, %arg) = @_;
1369 1437
1370 my $signal = uc $arg{signal} 1438 my $signal = uc $arg{signal}
1371 or Carp::croak "required option 'signal' is missing"; 1439 or Carp::croak "required option 'signal' is missing";
1372 1440
1373 if ($HAVE_ASYNC_INTERRUPT) { 1441 if ($HAVE_ASYNC_INTERRUPT) {
1374 # async::interrupt 1442 # async::interrupt
1375 1443
1376 $signal = sig2num $signal; 1444 $signal = sig2num $signal;
1377 $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; 1445 $SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1378 1446
1379 $SIG_ASY{$signal} ||= new Async::Interrupt 1447 $SIG_ASY{$signal} ||= new Async::Interrupt
1380 cb => sub { undef $SIG_EV{$signal} }, 1448 cb => sub { undef $SIG_EV{$signal} },
1381 signal => $signal, 1449 signal => $signal,
1382 pipe => [$SIGPIPE_R->filenos], 1450 pipe => [$SIGPIPE_R->filenos],
1383 pipe_autodrain => 0, 1451 pipe_autodrain => 0,
1384 ; 1452 ;
1385 1453
1386 } else { 1454 } else {
1387 # pure perl 1455 # pure perl
1388 1456
1389 # AE::Util has been loaded in signal 1457 # AE::Util has been loaded in signal
1390 $signal = sig2name $signal; 1458 $signal = sig2name $signal;
1391 $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; 1459 $SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1392 1460
1393 $SIG{$signal} ||= sub { 1461 $SIG{$signal} ||= sub {
1394 local $!; 1462 local $!;
1395 syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV; 1463 syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
1396 undef $SIG_EV{$signal}; 1464 undef $SIG_EV{$signal};
1465 };
1466
1467 # can't do signal processing without introducing races in pure perl,
1468 # so limit the signal latency.
1469 _sig_add;
1470 }
1471
1472 bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
1397 }; 1473 };
1398 1474
1399 # can't do signal processing without introducing races in pure perl, 1475 *AnyEvent::Base::signal::DESTROY = sub {
1400 # so limit the signal latency. 1476 my ($signal, $cb) = @{$_[0]};
1477
1401 _sig_add; 1478 _sig_del;
1402 }
1403 1479
1404 bless [$signal, $arg{cb}], "AnyEvent::Base::signal" 1480 delete $SIG_CB{$signal}{$cb};
1405}
1406 1481
1407sub signal { 1482 $HAVE_ASYNC_INTERRUPT
1408 # probe for availability of Async::Interrupt 1483 ? delete $SIG_ASY{$signal}
1409 if (_have_async_interrupt) { 1484 : # delete doesn't work with older perls - they then
1410 warn "AnyEvent: using Async::Interrupt for race-free signal handling.\n" if $VERBOSE >= 8; 1485 # print weird messages, or just unconditionally exit
1411 1486 # instead of getting the default action.
1412 $SIGPIPE_R = new Async::Interrupt::EventPipe; 1487 undef $SIG{$signal}
1413 $SIG_IO = AnyEvent->io (fh => $SIGPIPE_R->fileno, poll => "r", cb => \&_signal_exec); 1488 unless keys %{ $SIG_CB{$signal} };
1414
1415 } else {
1416 warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;
1417
1418 require Fcntl;
1419
1420 if (AnyEvent::WIN32) {
1421 require AnyEvent::Util;
1422
1423 ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
1424 AnyEvent::Util::fh_nonblocking ($SIGPIPE_R) if $SIGPIPE_R;
1425 AnyEvent::Util::fh_nonblocking ($SIGPIPE_W) if $SIGPIPE_W; # just in case
1426 } else {
1427 pipe $SIGPIPE_R, $SIGPIPE_W;
1428 fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R;
1429 fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case
1430
1431 # not strictly required, as $^F is normally 2, but let's make sure...
1432 fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;
1433 fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;
1434 } 1489 };
1435
1436 $SIGPIPE_R
1437 or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
1438
1439 $SIG_IO = AnyEvent->io (fh => $SIGPIPE_R, poll => "r", cb => \&_signal_exec);
1440 } 1490 };
1441 1491 die if $@;
1442 *signal = \&_signal;
1443 &signal 1492 &signal
1444}
1445
1446sub AnyEvent::Base::signal::DESTROY {
1447 my ($signal, $cb) = @{$_[0]};
1448
1449 _sig_del;
1450
1451 delete $SIG_CB{$signal}{$cb};
1452
1453 $HAVE_ASYNC_INTERRUPT
1454 ? delete $SIG_ASY{$signal}
1455 : # delete doesn't work with older perls - they then
1456 # print weird messages, or just unconditionally exit
1457 # instead of getting the default action.
1458 undef $SIG{$signal}
1459 unless keys %{ $SIG_CB{$signal} };
1460} 1493}
1461 1494
1462# default implementation for ->child 1495# default implementation for ->child
1463 1496
1464our %PID_CB; 1497our %PID_CB;
… …
1601 Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak}; 1634 Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak};
1602 wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0] 1635 wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0]
1603} 1636}
1604 1637
1605sub cb { 1638sub cb {
1606 $_[0]{_ae_cb} = $_[1] if @_ > 1; 1639 my $cv = shift;
1640
1641 @_
1642 and $cv->{_ae_cb} = shift
1643 and $cv->{_ae_sent}
1644 and (delete $cv->{_ae_cb})->($cv);
1645
1607 $_[0]{_ae_cb} 1646 $cv->{_ae_cb}
1608} 1647}
1609 1648
1610sub begin { 1649sub begin {
1611 ++$_[0]{_ae_counter}; 1650 ++$_[0]{_ae_counter};
1612 $_[0]{_ae_end_cb} = $_[1] if @_ > 1; 1651 $_[0]{_ae_end_cb} = $_[1] if @_ > 1;
… …
1618} 1657}
1619 1658
1620# undocumented/compatibility with pre-3.4 1659# undocumented/compatibility with pre-3.4
1621*broadcast = \&send; 1660*broadcast = \&send;
1622*wait = \&_wait; 1661*wait = \&_wait;
1662
1663#############################################################################
1664# "new" API, currently only emulation of it
1665#############################################################################
1666
1667package AE;
1668
1669sub io($$$) {
1670 AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2])
1671}
1672
1673sub timer($$$) {
1674 AnyEvent->timer (after => $_[0], interval => $_[1], cb => $_[2]);
1675}
1676
1677sub signal($$) {
1678 AnyEvent->signal (signal => $_[0], cb => $_[1]);
1679}
1680
1681sub child($$) {
1682 AnyEvent->child (pid => $_[0], cb => $_[1]);
1683}
1684
1685sub idle($) {
1686 AnyEvent->idle (cb => $_[0]);
1687}
1688
1689sub cv(;&) {
1690 AnyEvent->condvar (@_ ? (cb => $_[0]) : ())
1691}
1692
1693sub now() {
1694 AnyEvent->now
1695}
1696
1697sub now_update() {
1698 AnyEvent->now_update
1699}
1700
1701sub time() {
1702 AnyEvent->time
1703}
1623 1704
1624=head1 ERROR AND EXCEPTION HANDLING 1705=head1 ERROR AND EXCEPTION HANDLING
1625 1706
1626In general, AnyEvent does not do any error handling - it relies on the 1707In general, AnyEvent does not do any error handling - it relies on the
1627caller to do that if required. The L<AnyEvent::Strict> module (see also 1708caller to do that if required. The L<AnyEvent::Strict> module (see also

Diff Legend

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