[ViewVC] Diff of: cvs/AnyEvent/lib/AnyEvent.pm

Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.107 by root, Tue May 6 12:15:50 2008 UTC vs.
Revision 1.129 by elmex, Sat May 24 15:19:30 2008 UTC

…		…
1	=head1 NAME	1	=head1 => NAME
2		2
3	AnyEvent - provide framework for multiple event loops	3	AnyEvent - provide framework for multiple event loops
4		4
5	EV, Event, Coro::EV, Coro::Event, Glib, Tk, Perl, Event::Lib, Qt, POE - various supported event loops	5	EV, Event, Glib, Tk, Perl, Event::Lib, Qt, POE - various supported event loops
6		6
7	=head1 SYNOPSIS	7	=head1 SYNOPSIS
8		8
9	use AnyEvent;	9	use AnyEvent;
10		10
15	my $w = AnyEvent->timer (after => $seconds, cb => sub {	15	my $w = AnyEvent->timer (after => $seconds, cb => sub {
16	...	16	...
17	});	17	});
18		18
19	my $w = AnyEvent->condvar; # stores whether a condition was flagged	19	my $w = AnyEvent->condvar; # stores whether a condition was flagged
		20	$w->send; # wake up current and all future recv's
20	$w->wait; # enters "main loop" till $condvar gets ->send	21	$w->recv; # enters "main loop" till $condvar gets ->send
21	$w->send; # wake up current and all future wait's
22		22
23	=head1 WHY YOU SHOULD USE THIS MODULE (OR NOT)	23	=head1 WHY YOU SHOULD USE THIS MODULE (OR NOT)
24		24
25	Glib, POE, IO::Async, Event... CPAN offers event models by the dozen	25	Glib, POE, IO::Async, Event... CPAN offers event models by the dozen
26	nowadays. So what is different about AnyEvent?	26	nowadays. So what is different about AnyEvent?
…		…
57	as those use one of the supported event loops. It is trivial to add new	57	as those use one of the supported event loops. It is trivial to add new
58	event loops to AnyEvent, too, so it is future-proof).	58	event loops to AnyEvent, too, so it is future-proof).
59		59
60	In addition to being free of having to use I<the one and only true event	60	In addition to being free of having to use I<the one and only true event
61	model>, AnyEvent also is free of bloat and policy: with POE or similar	61	model>, AnyEvent also is free of bloat and policy: with POE or similar
62	modules, you get an enourmous amount of code and strict rules you have to	62	modules, you get an enormous amount of code and strict rules you have to
63	follow. AnyEvent, on the other hand, is lean and up to the point, by only	63	follow. AnyEvent, on the other hand, is lean and up to the point, by only
64	offering the functionality that is necessary, in as thin as a wrapper as	64	offering the functionality that is necessary, in as thin as a wrapper as
65	technically possible.	65	technically possible.
66		66
67	Of course, if you want lots of policy (this can arguably be somewhat	67	Of course, if you want lots of policy (this can arguably be somewhat
…		…
78	The interface itself is vaguely similar, but not identical to the L<Event>	78	The interface itself is vaguely similar, but not identical to the L<Event>
79	module.	79	module.
80		80
81	During the first call of any watcher-creation method, the module tries	81	During the first call of any watcher-creation method, the module tries
82	to detect the currently loaded event loop by probing whether one of the	82	to detect the currently loaded event loop by probing whether one of the
83	following modules is already loaded: L<Coro::EV>, L<Coro::Event>, L<EV>,	83	following modules is already loaded: L<EV>,
84	L<Event>, L<Glib>, L<AnyEvent::Impl::Perl>, L<Tk>, L<Event::Lib>, L<Qt>,	84	L<Event>, L<Glib>, L<AnyEvent::Impl::Perl>, L<Tk>, L<Event::Lib>, L<Qt>,
85	L<POE>. The first one found is used. If none are found, the module tries	85	L<POE>. The first one found is used. If none are found, the module tries
86	to load these modules (excluding Tk, Event::Lib, Qt and POE as the pure perl	86	to load these modules (excluding Tk, Event::Lib, Qt and POE as the pure perl
87	adaptor should always succeed) in the order given. The first one that can	87	adaptor should always succeed) in the order given. The first one that can
88	be successfully loaded will be used. If, after this, still none could be	88	be successfully loaded will be used. If, after this, still none could be
…		…
108		108
109	=head1 WATCHERS	109	=head1 WATCHERS
110		110
111	AnyEvent has the central concept of a I<watcher>, which is an object that	111	AnyEvent has the central concept of a I<watcher>, which is an object that
112	stores relevant data for each kind of event you are waiting for, such as	112	stores relevant data for each kind of event you are waiting for, such as
113	the callback to call, the filehandle to watch, etc.	113	the callback to call, the file handle to watch, etc.
114		114
115	These watchers are normal Perl objects with normal Perl lifetime. After	115	These watchers are normal Perl objects with normal Perl lifetime. After
116	creating a watcher it will immediately "watch" for events and invoke the	116	creating a watcher it will immediately "watch" for events and invoke the
117	callback when the event occurs (of course, only when the event model	117	callback when the event occurs (of course, only when the event model
118	is in control).	118	is in control).
…		…
237		237
238	Although the callback might get passed parameters, their value and	238	Although the callback might get passed parameters, their value and
239	presence is undefined and you cannot rely on them. Portable AnyEvent	239	presence is undefined and you cannot rely on them. Portable AnyEvent
240	callbacks cannot use arguments passed to signal watcher callbacks.	240	callbacks cannot use arguments passed to signal watcher callbacks.
241		241
242	Multiple signal occurances can be clumped together into one callback	242	Multiple signal occurrences can be clumped together into one callback
243	invocation, and callback invocation will be synchronous. synchronous means	243	invocation, and callback invocation will be synchronous. Synchronous means
244	that it might take a while until the signal gets handled by the process,	244	that it might take a while until the signal gets handled by the process,
245	but it is guarenteed not to interrupt any other callbacks.	245	but it is guaranteed not to interrupt any other callbacks.
246		246
247	The main advantage of using these watchers is that you can share a signal	247	The main advantage of using these watchers is that you can share a signal
248	between multiple watchers.	248	between multiple watchers.
249		249
250	This watcher might use C<%SIG>, so programs overwriting those signals	250	This watcher might use C<%SIG>, so programs overwriting those signals
…		…
278	C<fork> the child (alternatively, you can call C<AnyEvent::detect>).	278	C<fork> the child (alternatively, you can call C<AnyEvent::detect>).
279		279
280	Example: fork a process and wait for it	280	Example: fork a process and wait for it
281		281
282	my $done = AnyEvent->condvar;	282	my $done = AnyEvent->condvar;
283
284	AnyEvent::detect; # force event module to be initialised
285		283
286	my $pid = fork or exit 5;	284	my $pid = fork or exit 5;
287		285
288	my $w = AnyEvent->child (	286	my $w = AnyEvent->child (
289	pid => $pid,	287	pid => $pid,
…		…
293	$done->send;	291	$done->send;
294	},	292	},
295	);	293	);
296		294
297	# do something else, then wait for process exit	295	# do something else, then wait for process exit
298	$done->wait;	296	$done->recv;
299		297
300	=head2 CONDITION VARIABLES	298	=head2 CONDITION VARIABLES
301		299
302	If you are familiar with some event loops you will know that all of them	300	If you are familiar with some event loops you will know that all of them
303	require you to run some blocking "loop", "run" or similar function that	301	require you to run some blocking "loop", "run" or similar function that
…		…
312	Condition variables can be created by calling the C<< AnyEvent->condvar	310	Condition variables can be created by calling the C<< AnyEvent->condvar
313	>> method, usually without arguments. The only argument pair allowed is	311	>> method, usually without arguments. The only argument pair allowed is
314	C<cb>, which specifies a callback to be called when the condition variable	312	C<cb>, which specifies a callback to be called when the condition variable
315	becomes true.	313	becomes true.
316		314
317	After creation, the conditon variable is "false" until it becomes "true"	315	After creation, the condition variable is "false" until it becomes "true"
318	by calling the C<send> method.	316	by calling the C<send> method.
319		317
320	Condition variables are similar to callbacks, except that you can	318	Condition variables are similar to callbacks, except that you can
321	optionally wait for them. They can also be called merge points - points	319	optionally wait for them. They can also be called merge points - points
322	in time where multiple outstandign events have been processed. And yet	320	in time where multiple outstanding events have been processed. And yet
323	another way to call them is transations - each condition variable can be	321	another way to call them is transactions - each condition variable can be
324	used to represent a transaction, which finishes at some point and delivers	322	used to represent a transaction, which finishes at some point and delivers
325	a result.	323	a result.
326		324
327	Condition variables are very useful to signal that something has finished,	325	Condition variables are very useful to signal that something has finished,
328	for example, if you write a module that does asynchronous http requests,	326	for example, if you write a module that does asynchronous http requests,
329	then a condition variable would be the ideal candidate to signal the	327	then a condition variable would be the ideal candidate to signal the
330	availability of results. The user can either act when the callback is	328	availability of results. The user can either act when the callback is
331	called or can synchronously C<< ->wait >> for the results.	329	called or can synchronously C<< ->recv >> for the results.
332		330
333	You can also use them to simulate traditional event loops - for example,	331	You can also use them to simulate traditional event loops - for example,
334	you can block your main program until an event occurs - for example, you	332	you can block your main program until an event occurs - for example, you
335	could C<< ->wait >> in your main program until the user clicks the Quit	333	could C<< ->recv >> in your main program until the user clicks the Quit
336	button of your app, which would C<< ->send >> the "quit" event.	334	button of your app, which would C<< ->send >> the "quit" event.
337		335
338	Note that condition variables recurse into the event loop - if you have	336	Note that condition variables recurse into the event loop - if you have
339	two pieces of code that call C<< ->wait >> in a round-robbin fashion, you	337	two pieces of code that call C<< ->recv >> in a round-robin fashion, you
340	lose. Therefore, condition variables are good to export to your caller, but	338	lose. Therefore, condition variables are good to export to your caller, but
341	you should avoid making a blocking wait yourself, at least in callbacks,	339	you should avoid making a blocking wait yourself, at least in callbacks,
342	as this asks for trouble.	340	as this asks for trouble.
343		341
344	Condition variables are represented by hash refs in perl, and the keys	342	Condition variables are represented by hash refs in perl, and the keys
…		…
365	cb => sub { $result_ready->send },	363	cb => sub { $result_ready->send },
366	);	364	);
367		365
368	# this "blocks" (while handling events) till the callback	366	# this "blocks" (while handling events) till the callback
369	# calls send	367	# calls send
370	$result_ready->wait;	368	$result_ready->recv;
371		369
372	=head3 METHODS FOR PRODUCERS	370	=head3 METHODS FOR PRODUCERS
373		371
374	These methods should only be used by the producing side, i.e. the	372	These methods should only be used by the producing side, i.e. the
375	code/module that eventually sends the signal. Note that it is also	373	code/module that eventually sends the signal. Note that it is also
…		…
378		376
379	=over 4	377	=over 4
380		378
381	=item $cv->send (...)	379	=item $cv->send (...)
382		380
383	Flag the condition as ready - a running C<< ->wait >> and all further	381	Flag the condition as ready - a running C<< ->recv >> and all further
384	calls to C<wait> will (eventually) return after this method has been	382	calls to C<recv> will (eventually) return after this method has been
385	called. If nobody is waiting the send will be remembered.	383	called. If nobody is waiting the send will be remembered.
386		384
387	If a callback has been set on the condition variable, it is called	385	If a callback has been set on the condition variable, it is called
388	immediately from within send.	386	immediately from within send.
389		387
390	Any arguments passed to the C<send> call will be returned by all	388	Any arguments passed to the C<send> call will be returned by all
391	future C<< ->wait >> calls.	389	future C<< ->recv >> calls.
392		390
393	=item $cv->croak ($error)	391	=item $cv->croak ($error)
394		392
395	Similar to send, but causes all call's wait C<< ->wait >> to invoke	393	Similar to send, but causes all call's to C<< ->recv >> to invoke
396	C<Carp::croak> with the given error message/object/scalar.	394	C<Carp::croak> with the given error message/object/scalar.
397		395
398	This can be used to signal any errors to the condition variable	396	This can be used to signal any errors to the condition variable
399	user/consumer.	397	user/consumer.
400		398
401	=item $cv->begin ([group callback])	399	=item $cv->begin ([group callback])
402		400
403	=item $cv->end	401	=item $cv->end
		402
		403	These two methods are EXPERIMENTAL and MIGHT CHANGE.
404		404
405	These two methods can be used to combine many transactions/events into	405	These two methods can be used to combine many transactions/events into
406	one. For example, a function that pings many hosts in parallel might want	406	one. For example, a function that pings many hosts in parallel might want
407	to use a condition variable for the whole process.	407	to use a condition variable for the whole process.
408		408
…		…
443	doesn't execute once).	443	doesn't execute once).
444		444
445	This is the general pattern when you "fan out" into multiple subrequests:	445	This is the general pattern when you "fan out" into multiple subrequests:
446	use an outer C<begin>/C<end> pair to set the callback and ensure C<end>	446	use an outer C<begin>/C<end> pair to set the callback and ensure C<end>
447	is called at least once, and then, for each subrequest you start, call	447	is called at least once, and then, for each subrequest you start, call
448	C<begin> and for eahc subrequest you finish, call C<end>.	448	C<begin> and for each subrequest you finish, call C<end>.
449		449
450	=back	450	=back
451		451
452	=head3 METHODS FOR CONSUMERS	452	=head3 METHODS FOR CONSUMERS
453		453
454	These methods should only be used by the consuming side, i.e. the	454	These methods should only be used by the consuming side, i.e. the
455	code awaits the condition.	455	code awaits the condition.
456		456
457	=over 4	457	=over 4
458		458
459	=item $cv->wait	459	=item $cv->recv
460		460
461	Wait (blocking if necessary) until the C<< ->send >> or C<< ->croak	461	Wait (blocking if necessary) until the C<< ->send >> or C<< ->croak
462	>> methods have been called on c<$cv>, while servicing other watchers	462	>> methods have been called on c<$cv>, while servicing other watchers
463	normally.	463	normally.
464		464
…		…
475	(programs might want to do that to stay interactive), so I<if you are	475	(programs might want to do that to stay interactive), so I<if you are
476	using this from a module, never require a blocking wait>, but let the	476	using this from a module, never require a blocking wait>, but let the
477	caller decide whether the call will block or not (for example, by coupling	477	caller decide whether the call will block or not (for example, by coupling
478	condition variables with some kind of request results and supporting	478	condition variables with some kind of request results and supporting
479	callbacks so the caller knows that getting the result will not block,	479	callbacks so the caller knows that getting the result will not block,
480	while still suppporting blocking waits if the caller so desires).	480	while still supporting blocking waits if the caller so desires).
481		481
482	Another reason I<never> to C<< ->wait >> in a module is that you cannot	482	Another reason I<never> to C<< ->recv >> in a module is that you cannot
483	sensibly have two C<< ->wait >>'s in parallel, as that would require	483	sensibly have two C<< ->recv >>'s in parallel, as that would require
484	multiple interpreters or coroutines/threads, none of which C<AnyEvent>	484	multiple interpreters or coroutines/threads, none of which C<AnyEvent>
485	can supply (the coroutine-aware backends L<AnyEvent::Impl::CoroEV> and	485	can supply.
486	L<AnyEvent::Impl::CoroEvent> explicitly support concurrent C<< ->wait >>'s
487	from different coroutines, however).
488		486
		487	The L<Coro> module, however, I<can> and I<does> supply coroutines and, in
		488	fact, L<Coro::AnyEvent> replaces AnyEvent's condvars by coroutine-safe
		489	versions and also integrates coroutines into AnyEvent, making blocking
		490	C<< ->recv >> calls perfectly safe as long as they are done from another
		491	coroutine (one that doesn't run the event loop).
		492
489	You can ensure that C<< -wait >> never blocks by setting a callback and	493	You can ensure that C<< -recv >> never blocks by setting a callback and
490	only calling C<< ->wait >> from within that callback (or at a later	494	only calling C<< ->recv >> from within that callback (or at a later
491	time). This will work even when the event loop does not support blocking	495	time). This will work even when the event loop does not support blocking
492	waits otherwise.	496	waits otherwise.
493		497
494	=item $bool = $cv->ready	498	=item $bool = $cv->ready
495		499
…		…
500		504
501	This is a mutator function that returns the callback set and optionally	505	This is a mutator function that returns the callback set and optionally
502	replaces it before doing so.	506	replaces it before doing so.
503		507
504	The callback will be called when the condition becomes "true", i.e. when	508	The callback will be called when the condition becomes "true", i.e. when
505	C<send> or C<croak> are called. Calling C<wait> inside the callback	509	C<send> or C<croak> are called. Calling C<recv> inside the callback
506	or at any later time is guaranteed not to block.	510	or at any later time is guaranteed not to block.
507		511
508	=back	512	=back
509		513
510	=head1 GLOBAL VARIABLES AND FUNCTIONS	514	=head1 GLOBAL VARIABLES AND FUNCTIONS
…		…
519	C<AnyEvent::Impl:xxx> modules, but can be any other class in the case	523	C<AnyEvent::Impl:xxx> modules, but can be any other class in the case
520	AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode>).	524	AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode>).
521		525
522	The known classes so far are:	526	The known classes so far are:
523		527
524	AnyEvent::Impl::CoroEV based on Coro::EV, best choice.
525	AnyEvent::Impl::CoroEvent based on Coro::Event, second best choice.
526	AnyEvent::Impl::EV based on EV (an interface to libev, best choice).	528	AnyEvent::Impl::EV based on EV (an interface to libev, best choice).
527	AnyEvent::Impl::Event based on Event, second best choice.	529	AnyEvent::Impl::Event based on Event, second best choice.
528	AnyEvent::Impl::Perl pure-perl implementation, fast and portable.	530	AnyEvent::Impl::Perl pure-perl implementation, fast and portable.
529	AnyEvent::Impl::Glib based on Glib, third-best choice.	531	AnyEvent::Impl::Glib based on Glib, third-best choice.
530	AnyEvent::Impl::Tk based on Tk, very bad choice.	532	AnyEvent::Impl::Tk based on Tk, very bad choice.
…		…
547	Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model	549	Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model
548	if necessary. You should only call this function right before you would	550	if necessary. You should only call this function right before you would
549	have created an AnyEvent watcher anyway, that is, as late as possible at	551	have created an AnyEvent watcher anyway, that is, as late as possible at
550	runtime.	552	runtime.
551		553
		554	=item $guard = AnyEvent::post_detect { BLOCK }
		555
		556	Arranges for the code block to be executed as soon as the event model is
		557	autodetected (or immediately if this has already happened).
		558
		559	If called in scalar or list context, then it creates and returns an object
		560	that automatically removes the callback again when it is destroyed. See
		561	L<Coro::BDB> for a case where this is useful.
		562
		563	=item @AnyEvent::post_detect
		564
		565	If there are any code references in this array (you can C<push> to it
		566	before or after loading AnyEvent), then they will called directly after
		567	the event loop has been chosen.
		568
		569	You should check C<$AnyEvent::MODEL> before adding to this array, though:
		570	if it contains a true value then the event loop has already been detected,
		571	and the array will be ignored.
		572
		573	Best use C<AnyEvent::post_detect { BLOCK }> instead.
		574
552	=back	575	=back
553		576
554	=head1 WHAT TO DO IN A MODULE	577	=head1 WHAT TO DO IN A MODULE
555		578
556	As a module author, you should C<use AnyEvent> and call AnyEvent methods	579	As a module author, you should C<use AnyEvent> and call AnyEvent methods
…		…
559	Be careful when you create watchers in the module body - AnyEvent will	582	Be careful when you create watchers in the module body - AnyEvent will
560	decide which event module to use as soon as the first method is called, so	583	decide which event module to use as soon as the first method is called, so
561	by calling AnyEvent in your module body you force the user of your module	584	by calling AnyEvent in your module body you force the user of your module
562	to load the event module first.	585	to load the event module first.
563		586
564	Never call C<< ->wait >> on a condition variable unless you I<know> that	587	Never call C<< ->recv >> on a condition variable unless you I<know> that
565	the C<< ->send >> method has been called on it already. This is	588	the C<< ->send >> method has been called on it already. This is
566	because it will stall the whole program, and the whole point of using	589	because it will stall the whole program, and the whole point of using
567	events is to stay interactive.	590	events is to stay interactive.
568		591
569	It is fine, however, to call C<< ->wait >> when the user of your module	592	It is fine, however, to call C<< ->recv >> when the user of your module
570	requests it (i.e. if you create a http request object ad have a method	593	requests it (i.e. if you create a http request object ad have a method
571	called C<results> that returns the results, it should call C<< ->wait >>	594	called C<results> that returns the results, it should call C<< ->recv >>
572	freely, as the user of your module knows what she is doing. always).	595	freely, as the user of your module knows what she is doing. always).
573		596
574	=head1 WHAT TO DO IN THE MAIN PROGRAM	597	=head1 WHAT TO DO IN THE MAIN PROGRAM
575		598
576	There will always be a single main program - the only place that should	599	There will always be a single main program - the only place that should
…		…
610		633
611	Provide read and write buffers and manages watchers for reads and writes.	634	Provide read and write buffers and manages watchers for reads and writes.
612		635
613	=item L<AnyEvent::Socket>	636	=item L<AnyEvent::Socket>
614		637
615	Provides a means to do non-blocking connects, accepts etc.	638	Provides various utility functions for (internet protocol) sockets,
		639	addresses and name resolution. Also functions to create non-blocking tcp
		640	connections or tcp servers, with IPv6 and SRV record support and more.
616		641
617	=item L<AnyEvent::HTTPD>	642	=item L<AnyEvent::HTTPD>
618		643
619	Provides a simple web application server framework.	644	Provides a simple web application server framework.
620		645
621	=item L<AnyEvent::DNS>	646	=item L<AnyEvent::DNS>
622		647
623	Provides asynchronous DNS resolver capabilities, beyond what	648	Provides rich asynchronous DNS resolver capabilities.
624	L<AnyEvent::Util> offers.
625		649
626	=item L<AnyEvent::FastPing>	650	=item L<AnyEvent::FastPing>
627		651
628	The fastest ping in the west.	652	The fastest ping in the west.
629		653
…		…
644		668
645	High level API for event-based execution flow control.	669	High level API for event-based execution flow control.
646		670
647	=item L<Coro>	671	=item L<Coro>
648		672
649	Has special support for AnyEvent.	673	Has special support for AnyEvent via L<Coro::AnyEvent>.
		674
		675	=item L<AnyEvent::AIO>, L<IO::AIO>
		676
		677	Truly asynchronous I/O, should be in the toolbox of every event
		678	programmer. AnyEvent::AIO transparently fuses IO::AIO and AnyEvent
		679	together.
		680
		681	=item L<AnyEvent::BDB>, L<BDB>
		682
		683	Truly asynchronous Berkeley DB access. AnyEvent::AIO transparently fuses
		684	IO::AIO and AnyEvent together.
650		685
651	=item L<IO::Lambda>	686	=item L<IO::Lambda>
652		687
653	The lambda approach to I/O - don't ask, look there. Can use AnyEvent.	688	The lambda approach to I/O - don't ask, look there. Can use AnyEvent.
654
655	=item L<IO::AIO>
656
657	Truly asynchronous I/O, should be in the toolbox of every event
658	programmer. Can be trivially made to use AnyEvent.
659
660	=item L<BDB>
661
662	Truly asynchronous Berkeley DB access. Can be trivially made to use
663	AnyEvent.
664		689
665	=back	690	=back
666		691
667	=cut	692	=cut
668		693
…		…
671	no warnings;	696	no warnings;
672	use strict;	697	use strict;
673		698
674	use Carp;	699	use Carp;
675		700
676	our $VERSION = '3.3';	701	our $VERSION = '3.6';
677	our $MODEL;	702	our $MODEL;
678		703
679	our $AUTOLOAD;	704	our $AUTOLOAD;
680	our @ISA;	705	our @ISA;
681		706
682	our $verbose = $ENV{PERL_ANYEVENT_VERBOSE}*1;	707	our $verbose = $ENV{PERL_ANYEVENT_VERBOSE}*1;
683		708
684	our @REGISTRY;	709	our @REGISTRY;
685		710
		711	our %PROTOCOL; # (ipv4\|ipv6) => (1\|2)
		712
		713	{
		714	my $idx;
		715	$PROTOCOL{$_} = ++$idx
		716	for split /\s,\s/, $ENV{PERL_ANYEVENT_PROTOCOLS} \|\| "ipv4,ipv6";
		717	}
		718
686	my @models = (	719	my @models = (
687	[Coro::EV:: => AnyEvent::Impl::CoroEV::],
688	[Coro::Event:: => AnyEvent::Impl::CoroEvent::],
689	[EV:: => AnyEvent::Impl::EV::],	720	[EV:: => AnyEvent::Impl::EV::],
690	[Event:: => AnyEvent::Impl::Event::],	721	[Event:: => AnyEvent::Impl::Event::],
691	[Tk:: => AnyEvent::Impl::Tk::],	722	[Tk:: => AnyEvent::Impl::Tk::],
692	[Wx:: => AnyEvent::Impl::POE::],	723	[Wx:: => AnyEvent::Impl::POE::],
693	[Prima:: => AnyEvent::Impl::POE::],	724	[Prima:: => AnyEvent::Impl::POE::],
…		…
699	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza	730	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
700	);	731	);
701		732
702	our %method = map +($_ => 1), qw(io timer signal child condvar one_event DESTROY);	733	our %method = map +($_ => 1), qw(io timer signal child condvar one_event DESTROY);
703		734
		735	our @post_detect;
		736
		737	sub post_detect(&) {
		738	my ($cb) = @_;
		739
		740	if ($MODEL) {
		741	$cb->();
		742
		743	1
		744	} else {
		745	push @post_detect, $cb;
		746
		747	defined wantarray
		748	? bless \$cb, "AnyEvent::Util::PostDetect"
		749	: ()
		750	}
		751	}
		752
		753	sub AnyEvent::Util::PostDetect::DESTROY {
		754	@post_detect = grep $_ != ${$_[0]}, @post_detect;
		755	}
		756
704	sub detect() {	757	sub detect() {
705	unless ($MODEL) {	758	unless ($MODEL) {
706	no strict 'refs';	759	no strict 'refs';
707		760
708	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {	761	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {
…		…
741	last;	794	last;
742	}	795	}
743	}	796	}
744		797
745	$MODEL	798	$MODEL
746	or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV (or Coro+EV), Event (or Coro+Event) or Glib.";	799	or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.";
747	}	800	}
748	}	801	}
749		802
750	unshift @ISA, $MODEL;	803	unshift @ISA, $MODEL;
751	push @{"$MODEL\::ISA"}, "AnyEvent::Base";	804	push @{"$MODEL\::ISA"}, "AnyEvent::Base";
		805
		806	(shift @post_detect)->() while @post_detect;
752	}	807	}
753		808
754	$MODEL	809	$MODEL
755	}	810	}
756		811
…		…
766	$class->$func (@_);	821	$class->$func (@_);
767	}	822	}
768		823
769	package AnyEvent::Base;	824	package AnyEvent::Base;
770		825
771	# default implementation for ->condvar, ->wait, ->broadcast	826	# default implementation for ->condvar
772		827
773	sub condvar {	828	sub condvar {
774	bless \my $flag, "AnyEvent::Base::CondVar"	829	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, AnyEvent::CondVar::
775	}
776
777	sub AnyEvent::Base::CondVar::broadcast {
778	${$_[0]}++;
779	}
780
781	sub AnyEvent::Base::CondVar::wait {
782	AnyEvent->one_event while !${$_[0]};
783	}	830	}
784		831
785	# default implementation for ->signal	832	# default implementation for ->signal
786		833
787	our %SIG_CB;	834	our %SIG_CB;
…		…
861	delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} };	908	delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} };
862		909
863	undef $CHLD_W unless keys %PID_CB;	910	undef $CHLD_W unless keys %PID_CB;
864	}	911	}
865		912
		913	package AnyEvent::CondVar;
		914
		915	our @ISA = AnyEvent::CondVar::Base::;
		916
		917	package AnyEvent::CondVar::Base;
		918
		919	sub _send {
		920	# nop
		921	}
		922
		923	sub send {
		924	my $cv = shift;
		925	$cv->{_ae_sent} = [@_];
		926	(delete $cv->{_ae_cb})->($cv) if $cv->{_ae_cb};
		927	$cv->_send;
		928	}
		929
		930	sub croak {
		931	$_[0]{_ae_croak} = $_[1];
		932	$_[0]->send;
		933	}
		934
		935	sub ready {
		936	$_[0]{_ae_sent}
		937	}
		938
		939	sub _wait {
		940	AnyEvent->one_event while !$_[0]{_ae_sent};
		941	}
		942
		943	sub recv {
		944	$_[0]->_wait;
		945
		946	Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak};
		947	wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0]
		948	}
		949
		950	sub cb {
		951	$_[0]{_ae_cb} = $_[1] if @_ > 1;
		952	$_[0]{_ae_cb}
		953	}
		954
		955	sub begin {
		956	++$_[0]{_ae_counter};
		957	$_[0]{_ae_end_cb} = $_[1] if @_ > 1;
		958	}
		959
		960	sub end {
		961	return if --$_[0]{_ae_counter};
		962	&{ $_[0]{_ae_end_cb} \|\| sub { $_[0]->send } };
		963	}
		964
		965	# undocumented/compatibility with pre-3.4
		966	*broadcast = \&send;
		967	*wait = \&_wait;
		968
866	=head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE	969	=head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE
867		970
868	This is an advanced topic that you do not normally need to use AnyEvent in	971	This is an advanced topic that you do not normally need to use AnyEvent in
869	a module. This section is only of use to event loop authors who want to	972	a module. This section is only of use to event loop authors who want to
870	provide AnyEvent compatibility.	973	provide AnyEvent compatibility.
…		…
926	model it chooses.	1029	model it chooses.
927		1030
928	=item C<PERL_ANYEVENT_MODEL>	1031	=item C<PERL_ANYEVENT_MODEL>
929		1032
930	This can be used to specify the event model to be used by AnyEvent, before	1033	This can be used to specify the event model to be used by AnyEvent, before
931	autodetection and -probing kicks in. It must be a string consisting	1034	auto detection and -probing kicks in. It must be a string consisting
932	entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended	1035	entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended
933	and the resulting module name is loaded and if the load was successful,	1036	and the resulting module name is loaded and if the load was successful,
934	used as event model. If it fails to load AnyEvent will proceed with	1037	used as event model. If it fails to load AnyEvent will proceed with
935	autodetection and -probing.	1038	auto detection and -probing.
936		1039
937	This functionality might change in future versions.	1040	This functionality might change in future versions.
938		1041
939	For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you	1042	For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you
940	could start your program like this:	1043	could start your program like this:
941		1044
942	PERL_ANYEVENT_MODEL=Perl perl ...	1045	PERL_ANYEVENT_MODEL=Perl perl ...
		1046
		1047	=item C<PERL_ANYEVENT_PROTOCOLS>
		1048
		1049	Used by both L<AnyEvent::DNS> and L<AnyEvent::Socket> to determine preferences
		1050	for IPv4 or IPv6. The default is unspecified (and might change, or be the result
		1051	of auto probing).
		1052
		1053	Must be set to a comma-separated list of protocols or address families,
		1054	current supported: C<ipv4> and C<ipv6>. Only protocols mentioned will be
		1055	used, and preference will be given to protocols mentioned earlier in the
		1056	list.
		1057
		1058	This variable can effectively be used for denial-of-service attacks
		1059	against local programs (e.g. when setuid), although the impact is likely
		1060	small, as the program has to handle connection errors already-
		1061
		1062	Examples: C<PERL_ANYEVENT_PROTOCOLS=ipv4,ipv6> - prefer IPv4 over IPv6,
		1063	but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4>
		1064	- only support IPv4, never try to resolve or contact IPv6
		1065	addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or
		1066	IPv6, but prefer IPv6 over IPv4.
		1067
		1068	=item C<PERL_ANYEVENT_EDNS0>
		1069
		1070	Used by L<AnyEvent::DNS> to decide whether to use the EDNS0 extension
		1071	for DNS. This extension is generally useful to reduce DNS traffic, but
		1072	some (broken) firewalls drop such DNS packets, which is why it is off by
		1073	default.
		1074
		1075	Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce
		1076	EDNS0 in its DNS requests.
943		1077
944	=back	1078	=back
945		1079
946	=head1 EXAMPLE PROGRAM	1080	=head1 EXAMPLE PROGRAM
947		1081
…		…
958	poll => 'r',	1092	poll => 'r',
959	cb => sub {	1093	cb => sub {
960	warn "io event <$_[0]>\n"; # will always output <r>	1094	warn "io event <$_[0]>\n"; # will always output <r>
961	chomp (my $input = <STDIN>); # read a line	1095	chomp (my $input = <STDIN>); # read a line
962	warn "read: $input\n"; # output what has been read	1096	warn "read: $input\n"; # output what has been read
963	$cv->broadcast if $input =~ /^q/i; # quit program if /^q/i	1097	$cv->send if $input =~ /^q/i; # quit program if /^q/i
964	},	1098	},
965	);	1099	);
966		1100
967	my $time_watcher; # can only be used once	1101	my $time_watcher; # can only be used once
968		1102
…		…
973	});	1107	});
974	}	1108	}
975		1109
976	new_timer; # create first timer	1110	new_timer; # create first timer
977		1111
978	$cv->wait; # wait until user enters /^q/i	1112	$cv->recv; # wait until user enters /^q/i
979		1113
980	=head1 REAL-WORLD EXAMPLE	1114	=head1 REAL-WORLD EXAMPLE
981		1115
982	Consider the L<Net::FCP> module. It features (among others) the following	1116	Consider the L<Net::FCP> module. It features (among others) the following
983	API calls, which are to freenet what HTTP GET requests are to http:	1117	API calls, which are to freenet what HTTP GET requests are to http:
…		…
1033	syswrite $txn->{fh}, $txn->{request}	1167	syswrite $txn->{fh}, $txn->{request}
1034	or die "connection or write error";	1168	or die "connection or write error";
1035	$txn->{w} = AnyEvent->io (fh => $txn->{fh}, poll => 'r', cb => sub { $txn->fh_ready_r });	1169	$txn->{w} = AnyEvent->io (fh => $txn->{fh}, poll => 'r', cb => sub { $txn->fh_ready_r });
1036		1170
1037	Again, C<fh_ready_r> waits till all data has arrived, and then stores the	1171	Again, C<fh_ready_r> waits till all data has arrived, and then stores the
1038	result and signals any possible waiters that the request ahs finished:	1172	result and signals any possible waiters that the request has finished:
1039		1173
1040	sysread $txn->{fh}, $txn->{buf}, length $txn->{$buf};	1174	sysread $txn->{fh}, $txn->{buf}, length $txn->{$buf};
1041		1175
1042	if (end-of-file or data complete) {	1176	if (end-of-file or data complete) {
1043	$txn->{result} = $txn->{buf};	1177	$txn->{result} = $txn->{buf};
1044	$txn->{finished}->broadcast;	1178	$txn->{finished}->send;
1045	$txb->{cb}->($txn) of $txn->{cb}; # also call callback	1179	$txb->{cb}->($txn) of $txn->{cb}; # also call callback
1046	}	1180	}
1047		1181
1048	The C<result> method, finally, just waits for the finished signal (if the	1182	The C<result> method, finally, just waits for the finished signal (if the
1049	request was already finished, it doesn't wait, of course, and returns the	1183	request was already finished, it doesn't wait, of course, and returns the
1050	data:	1184	data:
1051		1185
1052	$txn->{finished}->wait;	1186	$txn->{finished}->recv;
1053	return $txn->{result};	1187	return $txn->{result};
1054		1188
1055	The actual code goes further and collects all errors (C<die>s, exceptions)	1189	The actual code goes further and collects all errors (C<die>s, exceptions)
1056	that occured during request processing. The C<result> method detects	1190	that occurred during request processing. The C<result> method detects
1057	whether an exception as thrown (it is stored inside the $txn object)	1191	whether an exception as thrown (it is stored inside the $txn object)
1058	and just throws the exception, which means connection errors and other	1192	and just throws the exception, which means connection errors and other
1059	problems get reported tot he code that tries to use the result, not in a	1193	problems get reported tot he code that tries to use the result, not in a
1060	random callback.	1194	random callback.
1061		1195
…		…
1092		1226
1093	my $quit = AnyEvent->condvar;	1227	my $quit = AnyEvent->condvar;
1094		1228
1095	$fcp->txn_client_get ($url)->cb (sub {	1229	$fcp->txn_client_get ($url)->cb (sub {
1096	...	1230	...
1097	$quit->broadcast;	1231	$quit->send;
1098	});	1232	});
1099		1233
1100	$quit->wait;	1234	$quit->recv;
1101		1235
1102		1236
1103	=head1 BENCHMARKS	1237	=head1 BENCHMARKS
1104		1238
1105	To give you an idea of the performance and overheads that AnyEvent adds	1239	To give you an idea of the performance and overheads that AnyEvent adds
…		…
1107	of various event loops I prepared some benchmarks.	1241	of various event loops I prepared some benchmarks.
1108		1242
1109	=head2 BENCHMARKING ANYEVENT OVERHEAD	1243	=head2 BENCHMARKING ANYEVENT OVERHEAD
1110		1244
1111	Here is a benchmark of various supported event models used natively and	1245	Here is a benchmark of various supported event models used natively and
1112	through anyevent. The benchmark creates a lot of timers (with a zero	1246	through AnyEvent. The benchmark creates a lot of timers (with a zero
1113	timeout) and I/O watchers (watching STDOUT, a pty, to become writable,	1247	timeout) and I/O watchers (watching STDOUT, a pty, to become writable,
1114	which it is), lets them fire exactly once and destroys them again.	1248	which it is), lets them fire exactly once and destroys them again.
1115		1249
1116	Source code for this benchmark is found as F<eg/bench> in the AnyEvent	1250	Source code for this benchmark is found as F<eg/bench> in the AnyEvent
1117	distribution.	1251	distribution.
…		…
1134	all watchers, to avoid adding memory overhead. That means closure creation	1268	all watchers, to avoid adding memory overhead. That means closure creation
1135	and memory usage is not included in the figures.	1269	and memory usage is not included in the figures.
1136		1270
1137	I<invoke> is the time, in microseconds, used to invoke a simple	1271	I<invoke> is the time, in microseconds, used to invoke a simple
1138	callback. The callback simply counts down a Perl variable and after it was	1272	callback. The callback simply counts down a Perl variable and after it was
1139	invoked "watcher" times, it would C<< ->broadcast >> a condvar once to	1273	invoked "watcher" times, it would C<< ->send >> a condvar once to
1140	signal the end of this phase.	1274	signal the end of this phase.
1141		1275
1142	I<destroy> is the time, in microseconds, that it takes to destroy a single	1276	I<destroy> is the time, in microseconds, that it takes to destroy a single
1143	watcher.	1277	watcher.
1144		1278
…		…
1240		1374
1241	=back	1375	=back
1242		1376
1243	=head2 BENCHMARKING THE LARGE SERVER CASE	1377	=head2 BENCHMARKING THE LARGE SERVER CASE
1244		1378
1245	This benchmark atcually benchmarks the event loop itself. It works by	1379	This benchmark actually benchmarks the event loop itself. It works by
1246	creating a number of "servers": each server consists of a socketpair, a	1380	creating a number of "servers": each server consists of a socket pair, a
1247	timeout watcher that gets reset on activity (but never fires), and an I/O	1381	timeout watcher that gets reset on activity (but never fires), and an I/O
1248	watcher waiting for input on one side of the socket. Each time the socket	1382	watcher waiting for input on one side of the socket. Each time the socket
1249	watcher reads a byte it will write that byte to a random other "server".	1383	watcher reads a byte it will write that byte to a random other "server".
1250		1384
1251	The effect is that there will be a lot of I/O watchers, only part of which	1385	The effect is that there will be a lot of I/O watchers, only part of which
1252	are active at any one point (so there is a constant number of active	1386	are active at any one point (so there is a constant number of active
1253	fds for each loop iterstaion, but which fds these are is random). The	1387	fds for each loop iteration, but which fds these are is random). The
1254	timeout is reset each time something is read because that reflects how	1388	timeout is reset each time something is read because that reflects how
1255	most timeouts work (and puts extra pressure on the event loops).	1389	most timeouts work (and puts extra pressure on the event loops).
1256		1390
1257	In this benchmark, we use 10000 socketpairs (20000 sockets), of which 100	1391	In this benchmark, we use 10000 socket pairs (20000 sockets), of which 100
1258	(1%) are active. This mirrors the activity of large servers with many	1392	(1%) are active. This mirrors the activity of large servers with many
1259	connections, most of which are idle at any one point in time.	1393	connections, most of which are idle at any one point in time.
1260		1394
1261	Source code for this benchmark is found as F<eg/bench2> in the AnyEvent	1395	Source code for this benchmark is found as F<eg/bench2> in the AnyEvent
1262	distribution.	1396	distribution.
…		…
1264	=head3 Explanation of the columns	1398	=head3 Explanation of the columns
1265		1399
1266	I<sockets> is the number of sockets, and twice the number of "servers" (as	1400	I<sockets> is the number of sockets, and twice the number of "servers" (as
1267	each server has a read and write socket end).	1401	each server has a read and write socket end).
1268		1402
1269	I<create> is the time it takes to create a socketpair (which is	1403	I<create> is the time it takes to create a socket pair (which is
1270	nontrivial) and two watchers: an I/O watcher and a timeout watcher.	1404	nontrivial) and two watchers: an I/O watcher and a timeout watcher.
1271		1405
1272	I<request>, the most important value, is the time it takes to handle a	1406	I<request>, the most important value, is the time it takes to handle a
1273	single "request", that is, reading the token from the pipe and forwarding	1407	single "request", that is, reading the token from the pipe and forwarding
1274	it to another server. This includes deleting the old timeout and creating	1408	it to another server. This includes deleting the old timeout and creating
…		…
1347	speed most when you have lots of watchers, not when you only have a few of	1481	speed most when you have lots of watchers, not when you only have a few of
1348	them).	1482	them).
1349		1483
1350	EV is again fastest.	1484	EV is again fastest.
1351		1485
1352	Perl again comes second. It is noticably faster than the C-based event	1486	Perl again comes second. It is noticeably faster than the C-based event
1353	loops Event and Glib, although the difference is too small to really	1487	loops Event and Glib, although the difference is too small to really
1354	matter.	1488	matter.
1355		1489
1356	POE also performs much better in this case, but is is still far behind the	1490	POE also performs much better in this case, but is is still far behind the
1357	others.	1491	others.
…		…
1397	probably even less useful to an attacker than PERL_ANYEVENT_MODEL).	1531	probably even less useful to an attacker than PERL_ANYEVENT_MODEL).
1398		1532
1399		1533
1400	=head1 SEE ALSO	1534	=head1 SEE ALSO
1401		1535
1402	Event modules: L<Coro::EV>, L<EV>, L<EV::Glib>, L<Glib::EV>,	1536	Utility functions: L<AnyEvent::Util>.
1403	L<Coro::Event>, L<Event>, L<Glib::Event>, L<Glib>, L<Coro>, L<Tk>,	1537
		1538	Event modules: L<EV>, L<EV::Glib>, L<Glib::EV>, L<Event>, L<Glib::Event>,
1404	L<Event::Lib>, L<Qt>, L<POE>.	1539	L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.
1405		1540
1406	Implementations: L<AnyEvent::Impl::CoroEV>, L<AnyEvent::Impl::EV>,	1541	Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,
1407	L<AnyEvent::Impl::CoroEvent>, L<AnyEvent::Impl::Event>, L<AnyEvent::Impl::Glib>,	1542	L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,
1408	L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>, L<AnyEvent::Impl::EventLib>,	1543	L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,
1409	L<AnyEvent::Impl::Qt>, L<AnyEvent::Impl::POE>.	1544	L<AnyEvent::Impl::POE>.
1410		1545
		1546	Non-blocking file handles, sockets, TCP clients and
		1547	servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>.
		1548
		1549	Asynchronous DNS: L<AnyEvent::DNS>.
		1550
		1551	Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>,
		1552
1411	Nontrivial usage examples: L<Net::FCP>, L<Net::XMPP2>.	1553	Nontrivial usage examples: L<Net::FCP>, L<Net::XMPP2>, L<AnyEvent::DNS>.
1412		1554
1413		1555
1414	=head1 AUTHOR	1556	=head1 AUTHOR
1415		1557
1416	Marc Lehmann <schmorp@schmorp.de>	1558	Marc Lehmann <schmorp@schmorp.de>

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Comparing AnyEvent/lib/AnyEvent.pm (file contents): Revision 1.107 by root, Tue May 6 12:15:50 2008 UTC vs. Revision 1.129 by elmex, Sat May 24 15:19:30 2008 UTC

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Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.107 by root, Tue May 6 12:15:50 2008 UTC vs.
Revision 1.129 by elmex, Sat May 24 15:19:30 2008 UTC