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1=head1 NAME 1=head1 NAME
2 2
3AnyEvent - provide framework for multiple event loops 3AnyEvent - the DBI of event loop programming
4 4
5EV, Event, Glib, Tk, Perl, Event::Lib, Qt and POE are various supported 5EV, Event, Glib, Tk, Perl, Event::Lib, Irssi, rxvt-unicode, IO::Async, Qt
6event loops. 6and POE are various supported event loops/environments.
7 7
8=head1 SYNOPSIS 8=head1 SYNOPSIS
9 9
10 use AnyEvent; 10 use AnyEvent;
11 11
40=head1 INTRODUCTION/TUTORIAL 40=head1 INTRODUCTION/TUTORIAL
41 41
42This manpage is mainly a reference manual. If you are interested 42This manpage is mainly a reference manual. If you are interested
43in a tutorial or some gentle introduction, have a look at the 43in a tutorial or some gentle introduction, have a look at the
44L<AnyEvent::Intro> manpage. 44L<AnyEvent::Intro> manpage.
45
46=head1 SUPPORT
47
48There is a mailinglist for discussing all things AnyEvent, and an IRC
49channel, too.
50
51See the AnyEvent project page at the B<Schmorpforge Ta-Sa Software
52Repository>, at L<http://anyevent.schmorp.de>, for more info.
45 53
46=head1 WHY YOU SHOULD USE THIS MODULE (OR NOT) 54=head1 WHY YOU SHOULD USE THIS MODULE (OR NOT)
47 55
48Glib, POE, IO::Async, Event... CPAN offers event models by the dozen 56Glib, POE, IO::Async, Event... CPAN offers event models by the dozen
49nowadays. So what is different about AnyEvent? 57nowadays. So what is different about AnyEvent?
173my variables are only visible after the statement in which they are 181my variables are only visible after the statement in which they are
174declared. 182declared.
175 183
176=head2 I/O WATCHERS 184=head2 I/O WATCHERS
177 185
186 $w = AnyEvent->io (
187 fh => <filehandle_or_fileno>,
188 poll => <"r" or "w">,
189 cb => <callback>,
190 );
191
178You 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
179with the following mandatory key-value pairs as arguments: 193with the following mandatory key-value pairs as arguments:
180 194
181C<fh> is the Perl I<file handle> (I<not> file descriptor) to watch 195C<fh> is the Perl I<file handle> (or a naked file descriptor) to watch
182for 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
183handle). Note that only file handles pointing to things for which 197handle). Note that only file handles pointing to things for which
184non-blocking operation makes sense are allowed. This includes sockets, 198non-blocking operation makes sense are allowed. This includes sockets,
185most character devices, pipes, fifos and so on, but not for example files 199most character devices, pipes, fifos and so on, but not for example files
186or block devices. 200or block devices.
211 undef $w; 225 undef $w;
212 }); 226 });
213 227
214=head2 TIME WATCHERS 228=head2 TIME WATCHERS
215 229
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
216You can create a time watcher by calling the C<< AnyEvent->timer >> 238You can create a time watcher by calling the C<< AnyEvent->timer >>
217method with the following mandatory arguments: 239method with the following mandatory arguments:
218 240
219C<after> specifies after how many seconds (fractional values are 241C<after> specifies after how many seconds (fractional values are
220supported) 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
347 369
348=back 370=back
349 371
350=head2 SIGNAL WATCHERS 372=head2 SIGNAL WATCHERS
351 373
374 $w = AnyEvent->signal (signal => <uppercase_signal_name>, cb => <callback>);
375
352You 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
353I<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
354callback to be invoked whenever a signal occurs. 378callback to be invoked whenever a signal occurs.
355 379
356Although the callback might get passed parameters, their value and 380Although the callback might get passed parameters, their value and
361invocation, and callback invocation will be synchronous. Synchronous means 385invocation, and callback invocation will be synchronous. Synchronous means
362that it might take a while until the signal gets handled by the process, 386that it might take a while until the signal gets handled by the process,
363but it is guaranteed not to interrupt any other callbacks. 387but it is guaranteed not to interrupt any other callbacks.
364 388
365The main advantage of using these watchers is that you can share a signal 389The main advantage of using these watchers is that you can share a signal
366between multiple watchers. 390between multiple watchers, and AnyEvent will ensure that signals will not
391interrupt your program at bad times.
367 392
368This watcher might use C<%SIG>, so programs overwriting those signals 393This watcher might use C<%SIG> (depending on the event loop used),
369directly will likely not work correctly. 394so programs overwriting those signals directly will likely not work
395correctly.
370 396
371Example: exit on SIGINT 397Example: exit on SIGINT
372 398
373 my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 }); 399 my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });
374 400
401=head3 Signal Races, Delays and Workarounds
402
403Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching
404callbacks to signals in a generic way, which is a pity, as you cannot
405do race-free signal handling in perl, requiring C libraries for
406this. AnyEvent will try to do it's best, which means in some cases,
407signals will be delayed. The maximum time a signal might be delayed is
408specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This
409variable can be changed only before the first signal watcher is created,
410and should be left alone otherwise. This variable determines how often
411AnyEvent polls for signals (in case a wake-up was missed). Higher values
412will cause fewer spurious wake-ups, which is better for power and CPU
413saving.
414
415All these problems can be avoided by installing the optional
416L<Async::Interrupt> module, which works with most event loops. It will not
417work with inherently broken event loops such as L<Event> or L<Event::Lib>
418(and not with L<POE> currently, as POE does it's own workaround with
419one-second latency). For those, you just have to suffer the delays.
420
375=head2 CHILD PROCESS WATCHERS 421=head2 CHILD PROCESS WATCHERS
376 422
423 $w = AnyEvent->child (pid => <process id>, cb => <callback>);
424
377You 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.
378 426
379The child process is specified by the C<pid> argument (if set to C<0>, it 427The child process is specified by the C<pid> argument (one some backends,
380watches for any child process exit). The watcher will triggered only when 428using C<0> watches for any child process exit, on others this will
381the child process has finished and an exit status is available, not on 429croak). The watcher will be triggered only when the child process has
382any trace events (stopped/continued). 430finished and an exit status is available, not on any trace events
431(stopped/continued).
383 432
384The callback will be called with the pid and exit status (as returned by 433The callback will be called with the pid and exit status (as returned by
385waitpid), so unlike other watcher types, you I<can> rely on child watcher 434waitpid), so unlike other watcher types, you I<can> rely on child watcher
386callback arguments. 435callback arguments.
387 436
403 452
404This means you cannot create a child watcher as the very first 453This means you cannot create a child watcher as the very first
405thing in an AnyEvent program, you I<have> to create at least one 454thing in an AnyEvent program, you I<have> to create at least one
406watcher before you C<fork> the child (alternatively, you can call 455watcher before you C<fork> the child (alternatively, you can call
407C<AnyEvent::detect>). 456C<AnyEvent::detect>).
457
458As most event loops do not support waiting for child events, they will be
459emulated by AnyEvent in most cases, in which the latency and race problems
460mentioned in the description of signal watchers apply.
408 461
409Example: fork a process and wait for it 462Example: fork a process and wait for it
410 463
411 my $done = AnyEvent->condvar; 464 my $done = AnyEvent->condvar;
412 465
424 # do something else, then wait for process exit 477 # do something else, then wait for process exit
425 $done->recv; 478 $done->recv;
426 479
427=head2 IDLE WATCHERS 480=head2 IDLE WATCHERS
428 481
482 $w = AnyEvent->idle (cb => <callback>);
483
429Sometimes 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
430to 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
431"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
432attention by the event loop". 487attention by the event loop".
433 488
459 }); 514 });
460 }); 515 });
461 516
462=head2 CONDITION VARIABLES 517=head2 CONDITION VARIABLES
463 518
519 $cv = AnyEvent->condvar;
520
521 $cv->send (<list>);
522 my @res = $cv->recv;
523
464If 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
465require you to run some blocking "loop", "run" or similar function that 525require you to run some blocking "loop", "run" or similar function that
466will actively watch for new events and call your callbacks. 526will actively watch for new events and call your callbacks.
467 527
468AnyEvent is different, it expects somebody else to run the event loop and 528AnyEvent is slightly different: it expects somebody else to run the event
469will only block when necessary (usually when told by the user). 529loop and will only block when necessary (usually when told by the user).
470 530
471The instrument to do that is called a "condition variable", so called 531The instrument to do that is called a "condition variable", so called
472because they represent a condition that must become true. 532because they represent a condition that must become true.
473 533
534Now is probably a good time to look at the examples further below.
535
474Condition variables can be created by calling the C<< AnyEvent->condvar 536Condition variables can be created by calling the C<< AnyEvent->condvar
475>> method, usually without arguments. The only argument pair allowed is 537>> method, usually without arguments. The only argument pair allowed is
476
477C<cb>, which specifies a callback to be called when the condition variable 538C<cb>, which specifies a callback to be called when the condition variable
478becomes true, with the condition variable as the first argument (but not 539becomes true, with the condition variable as the first argument (but not
479the results). 540the results).
480 541
481After creation, the condition variable is "false" until it becomes "true" 542After creation, the condition variable is "false" until it becomes "true"
486Condition variables are similar to callbacks, except that you can 547Condition variables are similar to callbacks, except that you can
487optionally wait for them. They can also be called merge points - points 548optionally wait for them. They can also be called merge points - points
488in time where multiple outstanding events have been processed. And yet 549in time where multiple outstanding events have been processed. And yet
489another way to call them is transactions - each condition variable can be 550another way to call them is transactions - each condition variable can be
490used to represent a transaction, which finishes at some point and delivers 551used to represent a transaction, which finishes at some point and delivers
491a result. 552a result. And yet some people know them as "futures" - a promise to
553compute/deliver something that you can wait for.
492 554
493Condition variables are very useful to signal that something has finished, 555Condition variables are very useful to signal that something has finished,
494for example, if you write a module that does asynchronous http requests, 556for example, if you write a module that does asynchronous http requests,
495then a condition variable would be the ideal candidate to signal the 557then a condition variable would be the ideal candidate to signal the
496availability of results. The user can either act when the callback is 558availability of results. The user can either act when the callback is
530 after => 1, 592 after => 1,
531 cb => sub { $result_ready->send }, 593 cb => sub { $result_ready->send },
532 ); 594 );
533 595
534 # this "blocks" (while handling events) till the callback 596 # this "blocks" (while handling events) till the callback
535 # calls send 597 # calls -<send
536 $result_ready->recv; 598 $result_ready->recv;
537 599
538Example: wait for a timer, but take advantage of the fact that 600Example: wait for a timer, but take advantage of the fact that condition
539condition variables are also code references. 601variables are also callable directly.
540 602
541 my $done = AnyEvent->condvar; 603 my $done = AnyEvent->condvar;
542 my $delay = AnyEvent->timer (after => 5, cb => $done); 604 my $delay = AnyEvent->timer (after => 5, cb => $done);
543 $done->recv; 605 $done->recv;
544 606
550 612
551 ... 613 ...
552 614
553 my @info = $couchdb->info->recv; 615 my @info = $couchdb->info->recv;
554 616
555And this is how you would just ste a callback to be called whenever the 617And this is how you would just set a callback to be called whenever the
556results are available: 618results are available:
557 619
558 $couchdb->info->cb (sub { 620 $couchdb->info->cb (sub {
559 my @info = $_[0]->recv; 621 my @info = $_[0]->recv;
560 }); 622 });
578immediately from within send. 640immediately from within send.
579 641
580Any arguments passed to the C<send> call will be returned by all 642Any arguments passed to the C<send> call will be returned by all
581future C<< ->recv >> calls. 643future C<< ->recv >> calls.
582 644
583Condition variables are overloaded so one can call them directly 645Condition variables are overloaded so one can call them directly (as if
584(as a code reference). Calling them directly is the same as calling 646they were a code reference). Calling them directly is the same as calling
585C<send>. Note, however, that many C-based event loops do not handle 647C<send>.
586overloading, so as tempting as it may be, passing a condition variable
587instead of a callback does not work. Both the pure perl and EV loops
588support overloading, however, as well as all functions that use perl to
589invoke a callback (as in L<AnyEvent::Socket> and L<AnyEvent::DNS> for
590example).
591 648
592=item $cv->croak ($error) 649=item $cv->croak ($error)
593 650
594Similar to send, but causes all call's to C<< ->recv >> to invoke 651Similar to send, but causes all call's to C<< ->recv >> to invoke
595C<Carp::croak> with the given error message/object/scalar. 652C<Carp::croak> with the given error message/object/scalar.
596 653
597This can be used to signal any errors to the condition variable 654This can be used to signal any errors to the condition variable
598user/consumer. 655user/consumer. Doing it this way instead of calling C<croak> directly
656delays the error detetcion, but has the overwhelmign advantage that it
657diagnoses the error at the place where the result is expected, and not
658deep in some event clalback without connection to the actual code causing
659the problem.
599 660
600=item $cv->begin ([group callback]) 661=item $cv->begin ([group callback])
601 662
602=item $cv->end 663=item $cv->end
603 664
699function will call C<croak>. 760function will call C<croak>.
700 761
701In list context, all parameters passed to C<send> will be returned, 762In list context, all parameters passed to C<send> will be returned,
702in scalar context only the first one will be returned. 763in scalar context only the first one will be returned.
703 764
765Note that doing a blocking wait in a callback is not supported by any
766event loop, that is, recursive invocation of a blocking C<< ->recv
767>> is not allowed, and the C<recv> call will C<croak> if such a
768condition is detected. This condition can be slightly loosened by using
769L<Coro::AnyEvent>, which allows you to do a blocking C<< ->recv >> from
770any thread that doesn't run the event loop itself.
771
704Not all event models support a blocking wait - some die in that case 772Not all event models support a blocking wait - some die in that case
705(programs might want to do that to stay interactive), so I<if you are 773(programs might want to do that to stay interactive), so I<if you are
706using this from a module, never require a blocking wait>, but let the 774using this from a module, never require a blocking wait>. Instead, let the
707caller decide whether the call will block or not (for example, by coupling 775caller decide whether the call will block or not (for example, by coupling
708condition variables with some kind of request results and supporting 776condition variables with some kind of request results and supporting
709callbacks so the caller knows that getting the result will not block, 777callbacks so the caller knows that getting the result will not block,
710while still supporting blocking waits if the caller so desires). 778while still supporting blocking waits if the caller so desires).
711 779
712Another reason I<never> to C<< ->recv >> in a module is that you cannot
713sensibly have two C<< ->recv >>'s in parallel, as that would require
714multiple interpreters or coroutines/threads, none of which C<AnyEvent>
715can supply.
716
717The L<Coro> module, however, I<can> and I<does> supply coroutines and, in
718fact, L<Coro::AnyEvent> replaces AnyEvent's condvars by coroutine-safe
719versions and also integrates coroutines into AnyEvent, making blocking
720C<< ->recv >> calls perfectly safe as long as they are done from another
721coroutine (one that doesn't run the event loop).
722
723You can ensure that C<< -recv >> never blocks by setting a callback and 780You can ensure that C<< -recv >> never blocks by setting a callback and
724only calling C<< ->recv >> from within that callback (or at a later 781only calling C<< ->recv >> from within that callback (or at a later
725time). This will work even when the event loop does not support blocking 782time). This will work even when the event loop does not support blocking
726waits otherwise. 783waits otherwise.
727 784
733=item $cb = $cv->cb ($cb->($cv)) 790=item $cb = $cv->cb ($cb->($cv))
734 791
735This is a mutator function that returns the callback set and optionally 792This is a mutator function that returns the callback set and optionally
736replaces it before doing so. 793replaces it before doing so.
737 794
738The callback will be called when the condition becomes "true", i.e. when 795The callback will be called when the condition becomes (or already was)
739C<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
740variable itself. Calling C<recv> inside the callback or at any later time 797the only argument being the condition variable itself. Calling C<recv>
741is guaranteed not to block. 798inside the callback or at any later time is guaranteed not to block.
742 799
743=back 800=back
744 801
802=head1 SUPPORTED EVENT LOOPS/BACKENDS
803
804The available backend classes are (every class has its own manpage):
805
806=over 4
807
808=item Backends that are autoprobed when no other event loop can be found.
809
810EV is the preferred backend when no other event loop seems to be in
811use. If EV is not installed, then AnyEvent will try Event, and, failing
812that, will fall back to its own pure-perl implementation, which is
813available everywhere as it comes with AnyEvent itself.
814
815 AnyEvent::Impl::EV based on EV (interface to libev, best choice).
816 AnyEvent::Impl::Event based on Event, very stable, few glitches.
817 AnyEvent::Impl::Perl pure-perl implementation, fast and portable.
818
819=item Backends that are transparently being picked up when they are used.
820
821These will be used when they are currently loaded when the first watcher
822is created, in which case it is assumed that the application is using
823them. This means that AnyEvent will automatically pick the right backend
824when the main program loads an event module before anything starts to
825create watchers. Nothing special needs to be done by the main program.
826
827 AnyEvent::Impl::Glib based on Glib, slow but very stable.
828 AnyEvent::Impl::Tk based on Tk, very broken.
829 AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
830 AnyEvent::Impl::POE based on POE, very slow, some limitations.
831 AnyEvent::Impl::Irssi used when running within irssi.
832
833=item Backends with special needs.
834
835Qt requires the Qt::Application to be instantiated first, but will
836otherwise be picked up automatically. As long as the main program
837instantiates the application before any AnyEvent watchers are created,
838everything should just work.
839
840 AnyEvent::Impl::Qt based on Qt.
841
842Support for IO::Async can only be partial, as it is too broken and
843architecturally limited to even support the AnyEvent API. It also
844is the only event loop that needs the loop to be set explicitly, so
845it can only be used by a main program knowing about AnyEvent. See
846L<AnyEvent::Impl::Async> for the gory details.
847
848 AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed.
849
850=item Event loops that are indirectly supported via other backends.
851
852Some event loops can be supported via other modules:
853
854There is no direct support for WxWidgets (L<Wx>) or L<Prima>.
855
856B<WxWidgets> has no support for watching file handles. However, you can
857use WxWidgets through the POE adaptor, as POE has a Wx backend that simply
858polls 20 times per second, which was considered to be too horrible to even
859consider for AnyEvent.
860
861B<Prima> is not supported as nobody seems to be using it, but it has a POE
862backend, so it can be supported through POE.
863
864AnyEvent knows about both L<Prima> and L<Wx>, however, and will try to
865load L<POE> when detecting them, in the hope that POE will pick them up,
866in which case everything will be automatic.
867
868=back
869
745=head1 GLOBAL VARIABLES AND FUNCTIONS 870=head1 GLOBAL VARIABLES AND FUNCTIONS
746 871
872These are not normally required to use AnyEvent, but can be useful to
873write AnyEvent extension modules.
874
747=over 4 875=over 4
748 876
749=item $AnyEvent::MODEL 877=item $AnyEvent::MODEL
750 878
751Contains C<undef> until the first watcher is being created. Then it 879Contains C<undef> until the first watcher is being created, before the
880backend has been autodetected.
881
752contains the event model that is being used, which is the name of the 882Afterwards it contains the event model that is being used, which is the
753Perl class implementing the model. This class is usually one of the 883name of the Perl class implementing the model. This class is usually one
754C<AnyEvent::Impl:xxx> modules, but can be any other class in the case 884of the C<AnyEvent::Impl:xxx> modules, but can be any other class in the
755AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode>). 885case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it
756 886will be C<urxvt::anyevent>).
757The known classes so far are:
758
759 AnyEvent::Impl::EV based on EV (an interface to libev, best choice).
760 AnyEvent::Impl::Event based on Event, second best choice.
761 AnyEvent::Impl::Perl pure-perl implementation, fast and portable.
762 AnyEvent::Impl::Glib based on Glib, third-best choice.
763 AnyEvent::Impl::Tk based on Tk, very bad choice.
764 AnyEvent::Impl::Qt based on Qt, cannot be autoprobed (see its docs).
765 AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
766 AnyEvent::Impl::POE based on POE, not generic enough for full support.
767
768 # warning, support for IO::Async is only partial, as it is too broken
769 # and limited toe ven support the AnyEvent API. See AnyEvent::Impl::Async.
770 AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed (see its docs).
771
772There is no support for WxWidgets, as WxWidgets has no support for
773watching file handles. However, you can use WxWidgets through the
774POE Adaptor, as POE has a Wx backend that simply polls 20 times per
775second, which was considered to be too horrible to even consider for
776AnyEvent. Likewise, other POE backends can be used by AnyEvent by using
777it's adaptor.
778
779AnyEvent knows about L<Prima> and L<Wx> and will try to use L<POE> when
780autodetecting them.
781 887
782=item AnyEvent::detect 888=item AnyEvent::detect
783 889
784Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model 890Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model
785if necessary. You should only call this function right before you would 891if necessary. You should only call this function right before you would
786have created an AnyEvent watcher anyway, that is, as late as possible at 892have created an AnyEvent watcher anyway, that is, as late as possible at
787runtime. 893runtime, and not e.g. while initialising of your module.
894
895If you need to do some initialisation before AnyEvent watchers are
896created, use C<post_detect>.
788 897
789=item $guard = AnyEvent::post_detect { BLOCK } 898=item $guard = AnyEvent::post_detect { BLOCK }
790 899
791Arranges for the code block to be executed as soon as the event model is 900Arranges for the code block to be executed as soon as the event model is
792autodetected (or immediately if this has already happened). 901autodetected (or immediately if this has already happened).
793 902
903The block will be executed I<after> the actual backend has been detected
904(C<$AnyEvent::MODEL> is set), but I<before> any watchers have been
905created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do
906other initialisations - see the sources of L<AnyEvent::Strict> or
907L<AnyEvent::AIO> to see how this is used.
908
909The most common usage is to create some global watchers, without forcing
910event module detection too early, for example, L<AnyEvent::AIO> creates
911and installs the global L<IO::AIO> watcher in a C<post_detect> block to
912avoid autodetecting the event module at load time.
913
794If called in scalar or list context, then it creates and returns an object 914If called in scalar or list context, then it creates and returns an object
795that automatically removes the callback again when it is destroyed. See 915that automatically removes the callback again when it is destroyed (or
916C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for
796L<Coro::BDB> for a case where this is useful. 917a case where this is useful.
918
919Example: Create a watcher for the IO::AIO module and store it in
920C<$WATCHER>. Only do so after the event loop is initialised, though.
921
922 our WATCHER;
923
924 my $guard = AnyEvent::post_detect {
925 $WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb);
926 };
927
928 # the ||= is important in case post_detect immediately runs the block,
929 # as to not clobber the newly-created watcher. assigning both watcher and
930 # post_detect guard to the same variable has the advantage of users being
931 # able to just C<undef $WATCHER> if the watcher causes them grief.
932
933 $WATCHER ||= $guard;
797 934
798=item @AnyEvent::post_detect 935=item @AnyEvent::post_detect
799 936
800If there are any code references in this array (you can C<push> to it 937If there are any code references in this array (you can C<push> to it
801before or after loading AnyEvent), then they will called directly after 938before or after loading AnyEvent), then they will called directly after
802the event loop has been chosen. 939the event loop has been chosen.
803 940
804You should check C<$AnyEvent::MODEL> before adding to this array, though: 941You should check C<$AnyEvent::MODEL> before adding to this array, though:
805if it contains a true value then the event loop has already been detected, 942if it is defined then the event loop has already been detected, and the
806and the array will be ignored. 943array will be ignored.
807 944
808Best use C<AnyEvent::post_detect { BLOCK }> instead. 945Best use C<AnyEvent::post_detect { BLOCK }> when your application allows
946it,as it takes care of these details.
947
948This variable is mainly useful for modules that can do something useful
949when AnyEvent is used and thus want to know when it is initialised, but do
950not need to even load it by default. This array provides the means to hook
951into AnyEvent passively, without loading it.
809 952
810=back 953=back
811 954
812=head1 WHAT TO DO IN A MODULE 955=head1 WHAT TO DO IN A MODULE
813 956
868 1011
869 1012
870=head1 OTHER MODULES 1013=head1 OTHER MODULES
871 1014
872The following is a non-exhaustive list of additional modules that use 1015The following is a non-exhaustive list of additional modules that use
873AnyEvent and can therefore be mixed easily with other AnyEvent modules 1016AnyEvent as a client and can therefore be mixed easily with other AnyEvent
874in the same program. Some of the modules come with AnyEvent, some are 1017modules and other event loops in the same program. Some of the modules
875available via CPAN. 1018come with AnyEvent, most are available via CPAN.
876 1019
877=over 4 1020=over 4
878 1021
879=item L<AnyEvent::Util> 1022=item L<AnyEvent::Util>
880 1023
889 1032
890=item L<AnyEvent::Handle> 1033=item L<AnyEvent::Handle>
891 1034
892Provide read and write buffers, manages watchers for reads and writes, 1035Provide read and write buffers, manages watchers for reads and writes,
893supports raw and formatted I/O, I/O queued and fully transparent and 1036supports raw and formatted I/O, I/O queued and fully transparent and
894non-blocking SSL/TLS. 1037non-blocking SSL/TLS (via L<AnyEvent::TLS>.
895 1038
896=item L<AnyEvent::DNS> 1039=item L<AnyEvent::DNS>
897 1040
898Provides rich asynchronous DNS resolver capabilities. 1041Provides rich asynchronous DNS resolver capabilities.
899 1042
927 1070
928=item L<AnyEvent::GPSD> 1071=item L<AnyEvent::GPSD>
929 1072
930A non-blocking interface to gpsd, a daemon delivering GPS information. 1073A non-blocking interface to gpsd, a daemon delivering GPS information.
931 1074
1075=item L<AnyEvent::IRC>
1076
1077AnyEvent based IRC client module family (replacing the older Net::IRC3).
1078
1079=item L<AnyEvent::XMPP>
1080
1081AnyEvent based XMPP (Jabber protocol) module family (replacing the older
1082Net::XMPP2>.
1083
932=item L<AnyEvent::IGS> 1084=item L<AnyEvent::IGS>
933 1085
934A non-blocking interface to the Internet Go Server protocol (used by 1086A non-blocking interface to the Internet Go Server protocol (used by
935L<App::IGS>). 1087L<App::IGS>).
936 1088
937=item L<AnyEvent::IRC>
938
939AnyEvent based IRC client module family (replacing the older Net::IRC3).
940
941=item L<Net::XMPP2>
942
943AnyEvent based XMPP (Jabber protocol) module family.
944
945=item L<Net::FCP> 1089=item L<Net::FCP>
946 1090
947AnyEvent-based implementation of the Freenet Client Protocol, birthplace 1091AnyEvent-based implementation of the Freenet Client Protocol, birthplace
948of AnyEvent. 1092of AnyEvent.
949 1093
953 1097
954=item L<Coro> 1098=item L<Coro>
955 1099
956Has special support for AnyEvent via L<Coro::AnyEvent>. 1100Has special support for AnyEvent via L<Coro::AnyEvent>.
957 1101
958=item L<IO::Lambda>
959
960The lambda approach to I/O - don't ask, look there. Can use AnyEvent.
961
962=back 1102=back
963 1103
964=cut 1104=cut
965 1105
966package AnyEvent; 1106package AnyEvent;
967 1107
1108# basically a tuned-down version of common::sense
1109sub common_sense {
968no warnings; 1110 # no warnings
1111 ${^WARNING_BITS} ^= ${^WARNING_BITS};
969use strict qw(vars subs); 1112 # use strict vars subs
1113 $^H |= 0x00000600;
1114}
970 1115
1116BEGIN { AnyEvent::common_sense }
1117
971use Carp; 1118use Carp ();
972 1119
973our $VERSION = 4.45; 1120our $VERSION = 4.92;
974our $MODEL; 1121our $MODEL;
975 1122
976our $AUTOLOAD; 1123our $AUTOLOAD;
977our @ISA; 1124our @ISA;
978 1125
979our @REGISTRY; 1126our @REGISTRY;
980 1127
981our $WIN32; 1128our $WIN32;
1129
1130our $VERBOSE;
982 1131
983BEGIN { 1132BEGIN {
984 eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }"; 1133 eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }";
985 eval "sub TAINT(){ " . (${^TAINT}*1) . " }"; 1134 eval "sub TAINT(){ " . (${^TAINT}*1) . " }";
986 1135
987 delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV} 1136 delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}
988 if ${^TAINT}; 1137 if ${^TAINT};
989}
990 1138
991our $verbose = $ENV{PERL_ANYEVENT_VERBOSE}*1; 1139 $VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1;
1140
1141}
1142
1143our $MAX_SIGNAL_LATENCY = 10;
992 1144
993our %PROTOCOL; # (ipv4|ipv6) => (1|2), higher numbers are preferred 1145our %PROTOCOL; # (ipv4|ipv6) => (1|2), higher numbers are preferred
994 1146
995{ 1147{
996 my $idx; 1148 my $idx;
998 for reverse split /\s*,\s*/, 1150 for reverse split /\s*,\s*/,
999 $ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6"; 1151 $ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6";
1000} 1152}
1001 1153
1002my @models = ( 1154my @models = (
1003 [EV:: => AnyEvent::Impl::EV::], 1155 [EV:: => AnyEvent::Impl::EV:: , 1],
1004 [Event:: => AnyEvent::Impl::Event::], 1156 [Event:: => AnyEvent::Impl::Event::, 1],
1005 [AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl::], 1157 [AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl:: , 1],
1006 # everything below here will not be autoprobed 1158 # everything below here will not (normally) be autoprobed
1007 # as the pureperl backend should work everywhere 1159 # as the pureperl backend should work everywhere
1008 # and is usually faster 1160 # and is usually faster
1161 [Glib:: => AnyEvent::Impl::Glib:: , 1], # becomes extremely slow with many watchers
1162 [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy
1163 [Irssi:: => AnyEvent::Impl::Irssi::], # Irssi has a bogus "Event" package
1009 [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles 1164 [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
1010 [Glib:: => AnyEvent::Impl::Glib::], # becomes extremely slow with many watchers
1011 [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy
1012 [Qt:: => AnyEvent::Impl::Qt::], # requires special main program 1165 [Qt:: => AnyEvent::Impl::Qt::], # requires special main program
1013 [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza 1166 [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
1014 [Wx:: => AnyEvent::Impl::POE::], 1167 [Wx:: => AnyEvent::Impl::POE::],
1015 [Prima:: => AnyEvent::Impl::POE::], 1168 [Prima:: => AnyEvent::Impl::POE::],
1016 # IO::Async is just too broken - we would need workaorunds for its 1169 # IO::Async is just too broken - we would need workarounds for its
1017 # byzantine signal and broken child handling, among others. 1170 # byzantine signal and broken child handling, among others.
1018 # IO::Async is rather hard to detect, as it doesn't have any 1171 # IO::Async is rather hard to detect, as it doesn't have any
1019 # obvious default class. 1172 # obvious default class.
1020# [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program 1173# [0, IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program
1021# [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program 1174# [0, IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program
1022# [IO::Async::Notifier:: => AnyEvent::Impl::IOAsync::], # requires special main program 1175# [0, IO::Async::Notifier:: => AnyEvent::Impl::IOAsync::], # requires special main program
1023); 1176);
1024 1177
1025our %method = map +($_ => 1), 1178our %method = map +($_ => 1),
1026 qw(io timer time now now_update signal child idle condvar one_event DESTROY); 1179 qw(io timer time now now_update signal child idle condvar one_event DESTROY);
1027 1180
1031 my ($cb) = @_; 1184 my ($cb) = @_;
1032 1185
1033 if ($MODEL) { 1186 if ($MODEL) {
1034 $cb->(); 1187 $cb->();
1035 1188
1036 1 1189 undef
1037 } else { 1190 } else {
1038 push @post_detect, $cb; 1191 push @post_detect, $cb;
1039 1192
1040 defined wantarray 1193 defined wantarray
1041 ? bless \$cb, "AnyEvent::Util::postdetect" 1194 ? bless \$cb, "AnyEvent::Util::postdetect"
1047 @post_detect = grep $_ != ${$_[0]}, @post_detect; 1200 @post_detect = grep $_ != ${$_[0]}, @post_detect;
1048} 1201}
1049 1202
1050sub detect() { 1203sub detect() {
1051 unless ($MODEL) { 1204 unless ($MODEL) {
1052 no strict 'refs';
1053 local $SIG{__DIE__}; 1205 local $SIG{__DIE__};
1054 1206
1055 if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) { 1207 if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {
1056 my $model = "AnyEvent::Impl::$1"; 1208 my $model = "AnyEvent::Impl::$1";
1057 if (eval "require $model") { 1209 if (eval "require $model") {
1058 $MODEL = $model; 1210 $MODEL = $model;
1059 warn "AnyEvent: loaded model '$model' (forced by \$PERL_ANYEVENT_MODEL), using it.\n" if $verbose > 1; 1211 warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2;
1060 } else { 1212 } else {
1061 warn "AnyEvent: unable to load model '$model' (from \$PERL_ANYEVENT_MODEL):\n$@" if $verbose; 1213 warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE;
1062 } 1214 }
1063 } 1215 }
1064 1216
1065 # check for already loaded models 1217 # check for already loaded models
1066 unless ($MODEL) { 1218 unless ($MODEL) {
1067 for (@REGISTRY, @models) { 1219 for (@REGISTRY, @models) {
1068 my ($package, $model) = @$_; 1220 my ($package, $model) = @$_;
1069 if (${"$package\::VERSION"} > 0) { 1221 if (${"$package\::VERSION"} > 0) {
1070 if (eval "require $model") { 1222 if (eval "require $model") {
1071 $MODEL = $model; 1223 $MODEL = $model;
1072 warn "AnyEvent: autodetected model '$model', using it.\n" if $verbose > 1; 1224 warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2;
1073 last; 1225 last;
1074 } 1226 }
1075 } 1227 }
1076 } 1228 }
1077 1229
1078 unless ($MODEL) { 1230 unless ($MODEL) {
1079 # try to load a model 1231 # try to autoload a model
1080
1081 for (@REGISTRY, @models) { 1232 for (@REGISTRY, @models) {
1082 my ($package, $model) = @$_; 1233 my ($package, $model, $autoload) = @$_;
1234 if (
1235 $autoload
1083 if (eval "require $package" 1236 and eval "require $package"
1084 and ${"$package\::VERSION"} > 0 1237 and ${"$package\::VERSION"} > 0
1085 and eval "require $model") { 1238 and eval "require $model"
1239 ) {
1086 $MODEL = $model; 1240 $MODEL = $model;
1087 warn "AnyEvent: autoprobed model '$model', using it.\n" if $verbose > 1; 1241 warn "AnyEvent: autoloaded model '$model', using it.\n" if $VERBOSE >= 2;
1088 last; 1242 last;
1089 } 1243 }
1090 } 1244 }
1091 1245
1092 $MODEL 1246 $MODEL
1108 1262
1109sub AUTOLOAD { 1263sub AUTOLOAD {
1110 (my $func = $AUTOLOAD) =~ s/.*://; 1264 (my $func = $AUTOLOAD) =~ s/.*://;
1111 1265
1112 $method{$func} 1266 $method{$func}
1113 or croak "$func: not a valid method for AnyEvent objects"; 1267 or Carp::croak "$func: not a valid method for AnyEvent objects";
1114 1268
1115 detect unless $MODEL; 1269 detect unless $MODEL;
1116 1270
1117 my $class = shift; 1271 my $class = shift;
1118 $class->$func (@_); 1272 $class->$func (@_);
1123# allow only one watcher per fd, so we dup it to get a different one). 1277# allow only one watcher per fd, so we dup it to get a different one).
1124sub _dupfh($$;$$) { 1278sub _dupfh($$;$$) {
1125 my ($poll, $fh, $r, $w) = @_; 1279 my ($poll, $fh, $r, $w) = @_;
1126 1280
1127 # cygwin requires the fh mode to be matching, unix doesn't 1281 # cygwin requires the fh mode to be matching, unix doesn't
1128 my ($rw, $mode) = $poll eq "r" ? ($r, "<") 1282 my ($rw, $mode) = $poll eq "r" ? ($r, "<&") : ($w, ">&");
1129 : $poll eq "w" ? ($w, ">")
1130 : Carp::croak "AnyEvent->io requires poll set to either 'r' or 'w'";
1131 1283
1132 open my $fh2, "$mode&" . fileno $fh 1284 open my $fh2, $mode, $fh
1133 or die "cannot dup() filehandle: $!,"; 1285 or die "AnyEvent->io: cannot dup() filehandle in mode '$poll': $!,";
1134 1286
1135 # we assume CLOEXEC is already set by perl in all important cases 1287 # we assume CLOEXEC is already set by perl in all important cases
1136 1288
1137 ($fh2, $rw) 1289 ($fh2, $rw)
1138} 1290}
1139 1291
1292#############################################################################
1293# "new" API, currently only emulation of it
1294#############################################################################
1295
1296package AE;
1297
1298sub io($$$) {
1299 AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2])
1300}
1301
1302sub timer($$$) {
1303 AnyEvent->timer (after => $_[0], interval => $_[1], cb => $_[2]);
1304}
1305
1306sub signal($$) {
1307 AnyEvent->signal (signal => $_[0], cb => $_[1]);
1308}
1309
1310sub child($$) {
1311 AnyEvent->child (pid => $_[0], cb => $_[1]);
1312}
1313
1314sub idle($) {
1315 AnyEvent->idle (cb => $_[0]);
1316}
1317
1318sub cv(;&) {
1319 AnyEvent->condvar (@_ ? (cb => $_[0]) : ())
1320}
1321
1322sub now() {
1323 AnyEvent->now
1324}
1325
1326sub now_update() {
1327 AnyEvent->now_update
1328}
1329
1330sub time() {
1331 AnyEvent->time
1332}
1333
1140package AnyEvent::Base; 1334package AnyEvent::Base;
1141 1335
1142# default implementations for many methods 1336# default implementations for many methods
1143 1337
1144BEGIN { 1338sub _time {
1339 # probe for availability of Time::HiRes
1145 if (eval "use Time::HiRes (); Time::HiRes::time (); 1") { 1340 if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {
1341 warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8;
1146 *_time = \&Time::HiRes::time; 1342 *_time = \&Time::HiRes::time;
1147 # if (eval "use POSIX (); (POSIX::times())... 1343 # if (eval "use POSIX (); (POSIX::times())...
1148 } else { 1344 } else {
1345 warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE;
1149 *_time = sub { time }; # epic fail 1346 *_time = sub { time }; # epic fail
1150 } 1347 }
1348
1349 &_time
1151} 1350}
1152 1351
1153sub time { _time } 1352sub time { _time }
1154sub now { _time } 1353sub now { _time }
1155sub now_update { } 1354sub now_update { }
1160 bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar" 1359 bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"
1161} 1360}
1162 1361
1163# default implementation for ->signal 1362# default implementation for ->signal
1164 1363
1364our $HAVE_ASYNC_INTERRUPT;
1365
1366sub _have_async_interrupt() {
1367 $HAVE_ASYNC_INTERRUPT = 1*(!$ENV{PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT}
1368 && eval "use Async::Interrupt 1.0 (); 1")
1369 unless defined $HAVE_ASYNC_INTERRUPT;
1370
1371 $HAVE_ASYNC_INTERRUPT
1372}
1373
1165our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO); 1374our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);
1375our (%SIG_ASY, %SIG_ASY_W);
1376our ($SIG_COUNT, $SIG_TW);
1166 1377
1167sub _signal_exec { 1378sub _signal_exec {
1379 $HAVE_ASYNC_INTERRUPT
1380 ? $SIGPIPE_R->drain
1168 sysread $SIGPIPE_R, my $dummy, 4; 1381 : sysread $SIGPIPE_R, my $dummy, 9;
1169 1382
1170 while (%SIG_EV) { 1383 while (%SIG_EV) {
1171 for (keys %SIG_EV) { 1384 for (keys %SIG_EV) {
1172 delete $SIG_EV{$_}; 1385 delete $SIG_EV{$_};
1173 $_->() for values %{ $SIG_CB{$_} || {} }; 1386 $_->() for values %{ $SIG_CB{$_} || {} };
1174 } 1387 }
1175 } 1388 }
1176} 1389}
1177 1390
1391# install a dummy wakeup watcher to reduce signal catching latency
1392sub _sig_add() {
1393 unless ($SIG_COUNT++) {
1394 # try to align timer on a full-second boundary, if possible
1395 my $NOW = AE::now;
1396
1397 $SIG_TW = AE::timer
1398 $MAX_SIGNAL_LATENCY - ($NOW - int $NOW),
1399 $MAX_SIGNAL_LATENCY,
1400 sub { } # just for the PERL_ASYNC_CHECK
1401 ;
1402 }
1403}
1404
1405sub _sig_del {
1406 undef $SIG_TW
1407 unless --$SIG_COUNT;
1408}
1409
1410our $_sig_name_init; $_sig_name_init = sub {
1411 eval q{ # poor man's autoloading
1412 undef $_sig_name_init;
1413
1414 if (_have_async_interrupt) {
1415 *sig2num = \&Async::Interrupt::sig2num;
1416 *sig2name = \&Async::Interrupt::sig2name;
1417 } else {
1418 require Config;
1419
1420 my %signame2num;
1421 @signame2num{ split ' ', $Config::Config{sig_name} }
1422 = split ' ', $Config::Config{sig_num};
1423
1424 my @signum2name;
1425 @signum2name[values %signame2num] = keys %signame2num;
1426
1427 *sig2num = sub($) {
1428 $_[0] > 0 ? shift : $signame2num{+shift}
1429 };
1430 *sig2name = sub ($) {
1431 $_[0] > 0 ? $signum2name[+shift] : shift
1432 };
1433 }
1434 };
1435 die if $@;
1436};
1437
1438sub sig2num ($) { &$_sig_name_init; &sig2num }
1439sub sig2name($) { &$_sig_name_init; &sig2name }
1440
1178sub signal { 1441sub signal {
1179 my (undef, %arg) = @_; 1442 eval q{ # poor man's autoloading {}
1443 # probe for availability of Async::Interrupt
1444 if (_have_async_interrupt) {
1445 warn "AnyEvent: using Async::Interrupt for race-free signal handling.\n" if $VERBOSE >= 8;
1180 1446
1181 unless ($SIGPIPE_R) { 1447 $SIGPIPE_R = new Async::Interrupt::EventPipe;
1182 require Fcntl; 1448 $SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec;
1183 1449
1184 if (AnyEvent::WIN32) {
1185 require AnyEvent::Util;
1186
1187 ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
1188 AnyEvent::Util::fh_nonblocking ($SIGPIPE_R) if $SIGPIPE_R;
1189 AnyEvent::Util::fh_nonblocking ($SIGPIPE_W) if $SIGPIPE_W; # just in case
1190 } else { 1450 } else {
1451 warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;
1452
1453 require Fcntl;
1454
1455 if (AnyEvent::WIN32) {
1456 require AnyEvent::Util;
1457
1458 ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
1459 AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R;
1460 AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case
1461 } else {
1191 pipe $SIGPIPE_R, $SIGPIPE_W; 1462 pipe $SIGPIPE_R, $SIGPIPE_W;
1192 fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R; 1463 fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R;
1193 fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case 1464 fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case
1194 1465
1195 # not strictly required, as $^F is normally 2, but let's make sure... 1466 # not strictly required, as $^F is normally 2, but let's make sure...
1196 fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC; 1467 fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;
1197 fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC; 1468 fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;
1469 }
1470
1471 $SIGPIPE_R
1472 or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
1473
1474 $SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec;
1198 } 1475 }
1199 1476
1200 $SIGPIPE_R 1477 *signal = sub {
1201 or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n"; 1478 my (undef, %arg) = @_;
1202 1479
1203 $SIG_IO = AnyEvent->io (fh => $SIGPIPE_R, poll => "r", cb => \&_signal_exec);
1204 }
1205
1206 my $signal = uc $arg{signal} 1480 my $signal = uc $arg{signal}
1207 or Carp::croak "required option 'signal' is missing"; 1481 or Carp::croak "required option 'signal' is missing";
1208 1482
1483 if ($HAVE_ASYNC_INTERRUPT) {
1484 # async::interrupt
1485
1486 $signal = sig2num $signal;
1209 $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; 1487 $SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1488
1489 $SIG_ASY{$signal} ||= new Async::Interrupt
1490 cb => sub { undef $SIG_EV{$signal} },
1491 signal => $signal,
1492 pipe => [$SIGPIPE_R->filenos],
1493 pipe_autodrain => 0,
1494 ;
1495
1496 } else {
1497 # pure perl
1498
1499 # AE::Util has been loaded in signal
1500 $signal = sig2name $signal;
1501 $SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1502
1210 $SIG{$signal} ||= sub { 1503 $SIG{$signal} ||= sub {
1211 local $!; 1504 local $!;
1212 syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV; 1505 syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
1213 undef $SIG_EV{$signal}; 1506 undef $SIG_EV{$signal};
1507 };
1508
1509 # can't do signal processing without introducing races in pure perl,
1510 # so limit the signal latency.
1511 _sig_add;
1512 }
1513
1514 bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
1515 };
1516
1517 *AnyEvent::Base::signal::DESTROY = sub {
1518 my ($signal, $cb) = @{$_[0]};
1519
1520 _sig_del;
1521
1522 delete $SIG_CB{$signal}{$cb};
1523
1524 $HAVE_ASYNC_INTERRUPT
1525 ? delete $SIG_ASY{$signal}
1526 : # delete doesn't work with older perls - they then
1527 # print weird messages, or just unconditionally exit
1528 # instead of getting the default action.
1529 undef $SIG{$signal}
1530 unless keys %{ $SIG_CB{$signal} };
1531 };
1214 }; 1532 };
1215 1533 die if $@;
1216 bless [$signal, $arg{cb}], "AnyEvent::Base::signal" 1534 &signal
1217}
1218
1219sub AnyEvent::Base::signal::DESTROY {
1220 my ($signal, $cb) = @{$_[0]};
1221
1222 delete $SIG_CB{$signal}{$cb};
1223
1224 # delete doesn't work with older perls - they then
1225 # print weird messages, or just unconditionally exit
1226 # instead of getting the default action.
1227 undef $SIG{$signal} unless keys %{ $SIG_CB{$signal} };
1228} 1535}
1229 1536
1230# default implementation for ->child 1537# default implementation for ->child
1231 1538
1232our %PID_CB; 1539our %PID_CB;
1233our $CHLD_W; 1540our $CHLD_W;
1234our $CHLD_DELAY_W; 1541our $CHLD_DELAY_W;
1235our $WNOHANG; 1542our $WNOHANG;
1236 1543
1544sub _emit_childstatus($$) {
1545 my (undef, $rpid, $rstatus) = @_;
1546
1547 $_->($rpid, $rstatus)
1548 for values %{ $PID_CB{$rpid} || {} },
1549 values %{ $PID_CB{0} || {} };
1550}
1551
1237sub _sigchld { 1552sub _sigchld {
1553 my $pid;
1554
1555 AnyEvent->_emit_childstatus ($pid, $?)
1238 while (0 < (my $pid = waitpid -1, $WNOHANG)) { 1556 while ($pid = waitpid -1, $WNOHANG) > 0;
1239 $_->($pid, $?) for (values %{ $PID_CB{$pid} || {} }),
1240 (values %{ $PID_CB{0} || {} });
1241 }
1242} 1557}
1243 1558
1244sub child { 1559sub child {
1245 my (undef, %arg) = @_; 1560 my (undef, %arg) = @_;
1246 1561
1247 defined (my $pid = $arg{pid} + 0) 1562 defined (my $pid = $arg{pid} + 0)
1248 or Carp::croak "required option 'pid' is missing"; 1563 or Carp::croak "required option 'pid' is missing";
1249 1564
1250 $PID_CB{$pid}{$arg{cb}} = $arg{cb}; 1565 $PID_CB{$pid}{$arg{cb}} = $arg{cb};
1251 1566
1567 # WNOHANG is almost cetrainly 1 everywhere
1568 $WNOHANG ||= $^O =~ /^(?:openbsd|netbsd|linux|freebsd|cygwin|MSWin32)$/
1569 ? 1
1252 $WNOHANG ||= eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1; 1570 : eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1;
1253 1571
1254 unless ($CHLD_W) { 1572 unless ($CHLD_W) {
1255 $CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld); 1573 $CHLD_W = AE::signal CHLD => \&_sigchld;
1256 # child could be a zombie already, so make at least one round 1574 # child could be a zombie already, so make at least one round
1257 &_sigchld; 1575 &_sigchld;
1258 } 1576 }
1259 1577
1260 bless [$pid, $arg{cb}], "AnyEvent::Base::child" 1578 bless [$pid, $arg{cb}], "AnyEvent::Base::child"
1286 # never use more then 50% of the time for the idle watcher, 1604 # never use more then 50% of the time for the idle watcher,
1287 # within some limits 1605 # within some limits
1288 $w = 0.0001 if $w < 0.0001; 1606 $w = 0.0001 if $w < 0.0001;
1289 $w = 5 if $w > 5; 1607 $w = 5 if $w > 5;
1290 1608
1291 $w = AnyEvent->timer (after => $w, cb => $rcb); 1609 $w = AE::timer $w, 0, $rcb;
1292 } else { 1610 } else {
1293 # clean up... 1611 # clean up...
1294 undef $w; 1612 undef $w;
1295 undef $rcb; 1613 undef $rcb;
1296 } 1614 }
1297 }; 1615 };
1298 1616
1299 $w = AnyEvent->timer (after => 0.05, cb => $rcb); 1617 $w = AE::timer 0.05, 0, $rcb;
1300 1618
1301 bless \\$cb, "AnyEvent::Base::idle" 1619 bless \\$cb, "AnyEvent::Base::idle"
1302} 1620}
1303 1621
1304sub AnyEvent::Base::idle::DESTROY { 1622sub AnyEvent::Base::idle::DESTROY {
1309 1627
1310our @ISA = AnyEvent::CondVar::Base::; 1628our @ISA = AnyEvent::CondVar::Base::;
1311 1629
1312package AnyEvent::CondVar::Base; 1630package AnyEvent::CondVar::Base;
1313 1631
1314use overload 1632#use overload
1315 '&{}' => sub { my $self = shift; sub { $self->send (@_) } }, 1633# '&{}' => sub { my $self = shift; sub { $self->send (@_) } },
1316 fallback => 1; 1634# fallback => 1;
1635
1636# save 300+ kilobytes by dirtily hardcoding overloading
1637${"AnyEvent::CondVar::Base::OVERLOAD"}{dummy}++; # Register with magic by touching.
1638*{'AnyEvent::CondVar::Base::()'} = sub { }; # "Make it findable via fetchmethod."
1639*{'AnyEvent::CondVar::Base::(&{}'} = sub { my $self = shift; sub { $self->send (@_) } }; # &{}
1640${'AnyEvent::CondVar::Base::()'} = 1; # fallback
1641
1642our $WAITING;
1317 1643
1318sub _send { 1644sub _send {
1319 # nop 1645 # nop
1320} 1646}
1321 1647
1334sub ready { 1660sub ready {
1335 $_[0]{_ae_sent} 1661 $_[0]{_ae_sent}
1336} 1662}
1337 1663
1338sub _wait { 1664sub _wait {
1665 $WAITING
1666 and !$_[0]{_ae_sent}
1667 and Carp::croak "AnyEvent::CondVar: recursive blocking wait detected";
1668
1669 local $WAITING = 1;
1339 AnyEvent->one_event while !$_[0]{_ae_sent}; 1670 AnyEvent->one_event while !$_[0]{_ae_sent};
1340} 1671}
1341 1672
1342sub recv { 1673sub recv {
1343 $_[0]->_wait; 1674 $_[0]->_wait;
1345 Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak}; 1676 Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak};
1346 wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0] 1677 wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0]
1347} 1678}
1348 1679
1349sub cb { 1680sub cb {
1350 $_[0]{_ae_cb} = $_[1] if @_ > 1; 1681 my $cv = shift;
1682
1683 @_
1684 and $cv->{_ae_cb} = shift
1685 and $cv->{_ae_sent}
1686 and (delete $cv->{_ae_cb})->($cv);
1687
1351 $_[0]{_ae_cb} 1688 $cv->{_ae_cb}
1352} 1689}
1353 1690
1354sub begin { 1691sub begin {
1355 ++$_[0]{_ae_counter}; 1692 ++$_[0]{_ae_counter};
1356 $_[0]{_ae_end_cb} = $_[1] if @_ > 1; 1693 $_[0]{_ae_end_cb} = $_[1] if @_ > 1;
1405C<PERL_ANYEVENT_MODEL>. 1742C<PERL_ANYEVENT_MODEL>.
1406 1743
1407When set to C<2> or higher, cause AnyEvent to report to STDERR which event 1744When set to C<2> or higher, cause AnyEvent to report to STDERR which event
1408model it chooses. 1745model it chooses.
1409 1746
1747When set to C<8> or higher, then AnyEvent will report extra information on
1748which optional modules it loads and how it implements certain features.
1749
1410=item C<PERL_ANYEVENT_STRICT> 1750=item C<PERL_ANYEVENT_STRICT>
1411 1751
1412AnyEvent does not do much argument checking by default, as thorough 1752AnyEvent does not do much argument checking by default, as thorough
1413argument checking is very costly. Setting this variable to a true value 1753argument checking is very costly. Setting this variable to a true value
1414will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly 1754will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly
1415check the arguments passed to most method calls. If it finds any problems, 1755check the arguments passed to most method calls. If it finds any problems,
1416it will croak. 1756it will croak.
1417 1757
1418In other words, enables "strict" mode. 1758In other words, enables "strict" mode.
1419 1759
1420Unlike C<use strict>, it is definitely recommended to keep it off in 1760Unlike C<use strict> (or it's modern cousin, C<< use L<common::sense>
1421production. Keeping C<PERL_ANYEVENT_STRICT=1> in your environment while 1761>>, it is definitely recommended to keep it off in production. Keeping
1422developing programs can be very useful, however. 1762C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs
1763can be very useful, however.
1423 1764
1424=item C<PERL_ANYEVENT_MODEL> 1765=item C<PERL_ANYEVENT_MODEL>
1425 1766
1426This can be used to specify the event model to be used by AnyEvent, before 1767This can be used to specify the event model to be used by AnyEvent, before
1427auto detection and -probing kicks in. It must be a string consisting 1768auto detection and -probing kicks in. It must be a string consisting
1470 1811
1471=item C<PERL_ANYEVENT_MAX_FORKS> 1812=item C<PERL_ANYEVENT_MAX_FORKS>
1472 1813
1473The maximum number of child processes that C<AnyEvent::Util::fork_call> 1814The maximum number of child processes that C<AnyEvent::Util::fork_call>
1474will create in parallel. 1815will create in parallel.
1816
1817=item C<PERL_ANYEVENT_MAX_OUTSTANDING_DNS>
1818
1819The default value for the C<max_outstanding> parameter for the default DNS
1820resolver - this is the maximum number of parallel DNS requests that are
1821sent to the DNS server.
1822
1823=item C<PERL_ANYEVENT_RESOLV_CONF>
1824
1825The file to use instead of F</etc/resolv.conf> (or OS-specific
1826configuration) in the default resolver. When set to the empty string, no
1827default config will be used.
1828
1829=item C<PERL_ANYEVENT_CA_FILE>, C<PERL_ANYEVENT_CA_PATH>.
1830
1831When neither C<ca_file> nor C<ca_path> was specified during
1832L<AnyEvent::TLS> context creation, and either of these environment
1833variables exist, they will be used to specify CA certificate locations
1834instead of a system-dependent default.
1835
1836=item C<PERL_ANYEVENT_AVOID_GUARD> and C<PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT>
1837
1838When these are set to C<1>, then the respective modules are not
1839loaded. Mostly good for testing AnyEvent itself.
1475 1840
1476=back 1841=back
1477 1842
1478=head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE 1843=head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE
1479 1844
2018 2383
2019A handler for C<SIGCHLD> is installed by AnyEvent's child watcher 2384A handler for C<SIGCHLD> is installed by AnyEvent's child watcher
2020emulation for event loops that do not support them natively. Also, some 2385emulation for event loops that do not support them natively. Also, some
2021event loops install a similar handler. 2386event loops install a similar handler.
2022 2387
2023If, when AnyEvent is loaded, SIGCHLD is set to IGNORE, then AnyEvent will 2388Additionally, when AnyEvent is loaded and SIGCHLD is set to IGNORE, then
2024reset it to default, to avoid losing child exit statuses. 2389AnyEvent will reset it to default, to avoid losing child exit statuses.
2025 2390
2026=item SIGPIPE 2391=item SIGPIPE
2027 2392
2028A no-op handler is installed for C<SIGPIPE> when C<$SIG{PIPE}> is C<undef> 2393A no-op handler is installed for C<SIGPIPE> when C<$SIG{PIPE}> is C<undef>
2029when AnyEvent gets loaded. 2394when AnyEvent gets loaded.
2047 if $SIG{CHLD} eq 'IGNORE'; 2412 if $SIG{CHLD} eq 'IGNORE';
2048 2413
2049$SIG{PIPE} = sub { } 2414$SIG{PIPE} = sub { }
2050 unless defined $SIG{PIPE}; 2415 unless defined $SIG{PIPE};
2051 2416
2417=head1 RECOMMENDED/OPTIONAL MODULES
2418
2419One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and
2420it's built-in modules) are required to use it.
2421
2422That does not mean that AnyEvent won't take advantage of some additional
2423modules if they are installed.
2424
2425This section epxlains which additional modules will be used, and how they
2426affect AnyEvent's operetion.
2427
2428=over 4
2429
2430=item L<Async::Interrupt>
2431
2432This slightly arcane module is used to implement fast signal handling: To
2433my knowledge, there is no way to do completely race-free and quick
2434signal handling in pure perl. To ensure that signals still get
2435delivered, AnyEvent will start an interval timer to wake up perl (and
2436catch the signals) with some delay (default is 10 seconds, look for
2437C<$AnyEvent::MAX_SIGNAL_LATENCY>).
2438
2439If this module is available, then it will be used to implement signal
2440catching, which means that signals will not be delayed, and the event loop
2441will not be interrupted regularly, which is more efficient (And good for
2442battery life on laptops).
2443
2444This affects not just the pure-perl event loop, but also other event loops
2445that have no signal handling on their own (e.g. Glib, Tk, Qt).
2446
2447Some event loops (POE, Event, Event::Lib) offer signal watchers natively,
2448and either employ their own workarounds (POE) or use AnyEvent's workaround
2449(using C<$AnyEvent::MAX_SIGNAL_LATENCY>). Installing L<Async::Interrupt>
2450does nothing for those backends.
2451
2452=item L<EV>
2453
2454This module isn't really "optional", as it is simply one of the backend
2455event loops that AnyEvent can use. However, it is simply the best event
2456loop available in terms of features, speed and stability: It supports
2457the AnyEvent API optimally, implements all the watcher types in XS, does
2458automatic timer adjustments even when no monotonic clock is available,
2459can take avdantage of advanced kernel interfaces such as C<epoll> and
2460C<kqueue>, and is the fastest backend I<by far>. You can even embed
2461L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>).
2462
2463=item L<Guard>
2464
2465The guard module, when used, will be used to implement
2466C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a
2467lot less memory), but otherwise doesn't affect guard operation much. It is
2468purely used for performance.
2469
2470=item L<JSON> and L<JSON::XS>
2471
2472This module is required when you want to read or write JSON data via
2473L<AnyEvent::Handle>. It is also written in pure-perl, but can take
2474advantage of the ultra-high-speed L<JSON::XS> module when it is installed.
2475
2476In fact, L<AnyEvent::Handle> will use L<JSON::XS> by default if it is
2477installed.
2478
2479=item L<Net::SSLeay>
2480
2481Implementing TLS/SSL in Perl is certainly interesting, but not very
2482worthwhile: If this module is installed, then L<AnyEvent::Handle> (with
2483the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL.
2484
2485=item L<Time::HiRes>
2486
2487This module is part of perl since release 5.008. It will be used when the
2488chosen event library does not come with a timing source on it's own. The
2489pure-perl event loop (L<AnyEvent::Impl::Perl>) will additionally use it to
2490try to use a monotonic clock for timing stability.
2491
2492=back
2493
2494
2052=head1 FORK 2495=head1 FORK
2053 2496
2054Most event libraries are not fork-safe. The ones who are usually are 2497Most event libraries are not fork-safe. The ones who are usually are
2055because they rely on inefficient but fork-safe C<select> or C<poll> 2498because they rely on inefficient but fork-safe C<select> or C<poll>
2056calls. Only L<EV> is fully fork-aware. 2499calls. Only L<EV> is fully fork-aware.
2057 2500
2058If you have to fork, you must either do so I<before> creating your first 2501If you have to fork, you must either do so I<before> creating your first
2059watcher OR you must not use AnyEvent at all in the child. 2502watcher OR you must not use AnyEvent at all in the child OR you must do
2503something completely out of the scope of AnyEvent.
2060 2504
2061 2505
2062=head1 SECURITY CONSIDERATIONS 2506=head1 SECURITY CONSIDERATIONS
2063 2507
2064AnyEvent can be forced to load any event model via 2508AnyEvent can be forced to load any event model via
2102L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>. 2546L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.
2103 2547
2104Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>, 2548Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,
2105L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>, 2549L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,
2106L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>, 2550L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,
2107L<AnyEvent::Impl::POE>. 2551L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>, L<Anyevent::Impl::Irssi>.
2108 2552
2109Non-blocking file handles, sockets, TCP clients and 2553Non-blocking file handles, sockets, TCP clients and
2110servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>. 2554servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.
2111 2555
2112Asynchronous DNS: L<AnyEvent::DNS>. 2556Asynchronous DNS: L<AnyEvent::DNS>.
2113 2557
2114Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>, 2558Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>,
2559L<Coro::Event>,
2115 2560
2116Nontrivial usage examples: L<Net::FCP>, L<Net::XMPP2>, L<AnyEvent::DNS>. 2561Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::XMPP>,
2562L<AnyEvent::HTTP>.
2117 2563
2118 2564
2119=head1 AUTHOR 2565=head1 AUTHOR
2120 2566
2121 Marc Lehmann <schmorp@schmorp.de> 2567 Marc Lehmann <schmorp@schmorp.de>

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