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

Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.167 by root, Tue Jul 8 23:44:51 2008 UTC vs.
Revision 1.208 by root, Sun Apr 26 18:12:53 2009 UTC

…		…
6		6
7	=head1 SYNOPSIS	7	=head1 SYNOPSIS
8		8
9	use AnyEvent;	9	use AnyEvent;
10		10
		11	# file descriptor readable
11	my $w = AnyEvent->io (fh => $fh, poll => "r\|w", cb => sub {	12	my $w = AnyEvent->io (fh => $fh, poll => "r", cb => sub { ... });
		13
		14	# one-shot or repeating timers
		15	my $w = AnyEvent->timer (after => $seconds, cb => sub { ... });
		16	my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ...
		17
		18	print AnyEvent->now; # prints current event loop time
		19	print AnyEvent->time; # think Time::HiRes::time or simply CORE::time.
		20
		21	# POSIX signal
		22	my $w = AnyEvent->signal (signal => "TERM", cb => sub { ... });
		23
		24	# child process exit
		25	my $w = AnyEvent->child (pid => $pid, cb => sub {
		26	my ($pid, $status) = @_;
12	...	27	...
13	});	28	});
14		29
15	my $w = AnyEvent->timer (after => $seconds, cb => sub {	30	# called when event loop idle (if applicable)
16	...	31	my $w = AnyEvent->idle (cb => sub { ... });
17	});
18		32
19	my $w = AnyEvent->condvar; # stores whether a condition was flagged	33	my $w = AnyEvent->condvar; # stores whether a condition was flagged
20	$w->send; # wake up current and all future recv's	34	$w->send; # wake up current and all future recv's
21	$w->recv; # enters "main loop" till $condvar gets ->send	35	$w->recv; # enters "main loop" till $condvar gets ->send
		36	# use a condvar in callback mode:
		37	$w->cb (sub { $_[0]->recv });
22		38
23	=head1 INTRODUCTION/TUTORIAL	39	=head1 INTRODUCTION/TUTORIAL
24		40
25	This manpage is mainly a reference manual. If you are interested	41	This manpage is mainly a reference manual. If you are interested
26	in a tutorial or some gentle introduction, have a look at the	42	in a tutorial or some gentle introduction, have a look at the
…		…
33		49
34	Executive Summary: AnyEvent is I<compatible>, AnyEvent is I<free of	50	Executive Summary: AnyEvent is I<compatible>, AnyEvent is I<free of
35	policy> and AnyEvent is I<small and efficient>.	51	policy> and AnyEvent is I<small and efficient>.
36		52
37	First and foremost, I<AnyEvent is not an event model> itself, it only	53	First and foremost, I<AnyEvent is not an event model> itself, it only
38	interfaces to whatever event model the main program happens to use in a	54	interfaces to whatever event model the main program happens to use, in a
39	pragmatic way. For event models and certain classes of immortals alike,	55	pragmatic way. For event models and certain classes of immortals alike,
40	the statement "there can only be one" is a bitter reality: In general,	56	the statement "there can only be one" is a bitter reality: In general,
41	only one event loop can be active at the same time in a process. AnyEvent	57	only one event loop can be active at the same time in a process. AnyEvent
42	helps hiding the differences between those event loops.	58	cannot change this, but it can hide the differences between those event
		59	loops.
43		60
44	The goal of AnyEvent is to offer module authors the ability to do event	61	The goal of AnyEvent is to offer module authors the ability to do event
45	programming (waiting for I/O or timer events) without subscribing to a	62	programming (waiting for I/O or timer events) without subscribing to a
46	religion, a way of living, and most importantly: without forcing your	63	religion, a way of living, and most importantly: without forcing your
47	module users into the same thing by forcing them to use the same event	64	module users into the same thing by forcing them to use the same event
48	model you use.	65	model you use.
49		66
50	For modules like POE or IO::Async (which is a total misnomer as it is	67	For modules like POE or IO::Async (which is a total misnomer as it is
51	actually doing all I/O I<synchronously>...), using them in your module is	68	actually doing all I/O I<synchronously>...), using them in your module is
52	like joining a cult: After you joined, you are dependent on them and you	69	like joining a cult: After you joined, you are dependent on them and you
53	cannot use anything else, as it is simply incompatible to everything that	70	cannot use anything else, as they are simply incompatible to everything
54	isn't itself. What's worse, all the potential users of your module are	71	that isn't them. What's worse, all the potential users of your
55	I<also> forced to use the same event loop you use.	72	module are I<also> forced to use the same event loop you use.
56		73
57	AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works	74	AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works
58	fine. AnyEvent + Tk works fine etc. etc. but none of these work together	75	fine. AnyEvent + Tk works fine etc. etc. but none of these work together
59	with the rest: POE + IO::Async? No go. Tk + Event? No go. Again: if	76	with the rest: POE + IO::Async? No go. Tk + Event? No go. Again: if
60	your module uses one of those, every user of your module has to use it,	77	your module uses one of those, every user of your module has to use it,
61	too. But if your module uses AnyEvent, it works transparently with all	78	too. But if your module uses AnyEvent, it works transparently with all
62	event models it supports (including stuff like POE and IO::Async, as long	79	event models it supports (including stuff like IO::Async, as long as those
63	as those use one of the supported event loops. It is trivial to add new	80	use one of the supported event loops. It is trivial to add new event loops
64	event loops to AnyEvent, too, so it is future-proof).	81	to AnyEvent, too, so it is future-proof).
65		82
66	In addition to being free of having to use I<the one and only true event	83	In addition to being free of having to use I<the one and only true event
67	model>, AnyEvent also is free of bloat and policy: with POE or similar	84	model>, AnyEvent also is free of bloat and policy: with POE or similar
68	modules, you get an enormous amount of code and strict rules you have to	85	modules, you get an enormous amount of code and strict rules you have to
69	follow. AnyEvent, on the other hand, is lean and up to the point, by only	86	follow. AnyEvent, on the other hand, is lean and up to the point, by only
…		…
127	These watchers are normal Perl objects with normal Perl lifetime. After	144	These watchers are normal Perl objects with normal Perl lifetime. After
128	creating a watcher it will immediately "watch" for events and invoke the	145	creating a watcher it will immediately "watch" for events and invoke the
129	callback when the event occurs (of course, only when the event model	146	callback when the event occurs (of course, only when the event model
130	is in control).	147	is in control).
131		148
		149	Note that B<callbacks must not permanently change global variables>
		150	potentially in use by the event loop (such as C<$_> or C<$[>) and that B<<
		151	callbacks must not C<die> >>. The former is good programming practise in
		152	Perl and the latter stems from the fact that exception handling differs
		153	widely between event loops.
		154
132	To disable the watcher you have to destroy it (e.g. by setting the	155	To disable the watcher you have to destroy it (e.g. by setting the
133	variable you store it in to C<undef> or otherwise deleting all references	156	variable you store it in to C<undef> or otherwise deleting all references
134	to it).	157	to it).
135		158
136	All watchers are created by calling a method on the C<AnyEvent> class.	159	All watchers are created by calling a method on the C<AnyEvent> class.
…		…
152	=head2 I/O WATCHERS	175	=head2 I/O WATCHERS
153		176
154	You can create an I/O watcher by calling the C<< AnyEvent->io >> method	177	You can create an I/O watcher by calling the C<< AnyEvent->io >> method
155	with the following mandatory key-value pairs as arguments:	178	with the following mandatory key-value pairs as arguments:
156		179
157	C<fh> the Perl I<file handle> (I<not> file descriptor) to watch for events	180	C<fh> is the Perl I<file handle> (I<not> file descriptor) to watch
158	(AnyEvent might or might not keep a reference to this file handle). C<poll>	181	for events (AnyEvent might or might not keep a reference to this file
		182	handle). Note that only file handles pointing to things for which
		183	non-blocking operation makes sense are allowed. This includes sockets,
		184	most character devices, pipes, fifos and so on, but not for example files
		185	or block devices.
		186
159	must be a string that is either C<r> or C<w>, which creates a watcher	187	C<poll> must be a string that is either C<r> or C<w>, which creates a
160	waiting for "r"eadable or "w"ritable events, respectively. C<cb> is the	188	watcher waiting for "r"eadable or "w"ritable events, respectively.
		189
161	callback to invoke each time the file handle becomes ready.	190	C<cb> is the callback to invoke each time the file handle becomes ready.
162		191
163	Although the callback might get passed parameters, their value and	192	Although the callback might get passed parameters, their value and
164	presence is undefined and you cannot rely on them. Portable AnyEvent	193	presence is undefined and you cannot rely on them. Portable AnyEvent
165	callbacks cannot use arguments passed to I/O watcher callbacks.	194	callbacks cannot use arguments passed to I/O watcher callbacks.
166		195
…		…
298	In either case, if you care (and in most cases, you don't), then you	327	In either case, if you care (and in most cases, you don't), then you
299	can get whatever behaviour you want with any event loop, by taking the	328	can get whatever behaviour you want with any event loop, by taking the
300	difference between C<< AnyEvent->time >> and C<< AnyEvent->now >> into	329	difference between C<< AnyEvent->time >> and C<< AnyEvent->now >> into
301	account.	330	account.
302		331
		332	=item AnyEvent->now_update
		333
		334	Some event loops (such as L<EV> or L<AnyEvent::Impl::Perl>) cache
		335	the current time for each loop iteration (see the discussion of L<<
		336	AnyEvent->now >>, above).
		337
		338	When a callback runs for a long time (or when the process sleeps), then
		339	this "current" time will differ substantially from the real time, which
		340	might affect timers and time-outs.
		341
		342	When this is the case, you can call this method, which will update the
		343	event loop's idea of "current time".
		344
		345	Note that updating the time I<might> cause some events to be handled.
		346
303	=back	347	=back
304		348
305	=head2 SIGNAL WATCHERS	349	=head2 SIGNAL WATCHERS
306		350
307	You can watch for signals using a signal watcher, C<signal> is the signal	351	You can watch for signals using a signal watcher, C<signal> is the signal
…		…
330	=head2 CHILD PROCESS WATCHERS	374	=head2 CHILD PROCESS WATCHERS
331		375
332	You can also watch on a child process exit and catch its exit status.	376	You can also watch on a child process exit and catch its exit status.
333		377
334	The child process is specified by the C<pid> argument (if set to C<0>, it	378	The child process is specified by the C<pid> argument (if set to C<0>, it
335	watches for any child process exit). The watcher will trigger as often	379	watches for any child process exit). The watcher will triggered only when
336	as status change for the child are received. This works by installing a	380	the child process has finished and an exit status is available, not on
337	signal handler for C<SIGCHLD>. The callback will be called with the pid	381	any trace events (stopped/continued).
338	and exit status (as returned by waitpid), so unlike other watcher types,	382
339	you I<can> rely on child watcher callback arguments.	383	The callback will be called with the pid and exit status (as returned by
		384	waitpid), so unlike other watcher types, you I<can> rely on child watcher
		385	callback arguments.
		386
		387	This watcher type works by installing a signal handler for C<SIGCHLD>,
		388	and since it cannot be shared, nothing else should use SIGCHLD or reap
		389	random child processes (waiting for specific child processes, e.g. inside
		390	C<system>, is just fine).
340		391
341	There is a slight catch to child watchers, however: you usually start them	392	There is a slight catch to child watchers, however: you usually start them
342	I<after> the child process was created, and this means the process could	393	I<after> the child process was created, and this means the process could
343	have exited already (and no SIGCHLD will be sent anymore).	394	have exited already (and no SIGCHLD will be sent anymore).
344		395
…		…
366	);	417	);
367		418
368	# do something else, then wait for process exit	419	# do something else, then wait for process exit
369	$done->recv;	420	$done->recv;
370		421
		422	=head2 IDLE WATCHERS
		423
		424	Sometimes there is a need to do something, but it is not so important
		425	to do it instantly, but only when there is nothing better to do. This
		426	"nothing better to do" is usually defined to be "no other events need
		427	attention by the event loop".
		428
		429	Idle watchers ideally get invoked when the event loop has nothing
		430	better to do, just before it would block the process to wait for new
		431	events. Instead of blocking, the idle watcher is invoked.
		432
		433	Most event loops unfortunately do not really support idle watchers (only
		434	EV, Event and Glib do it in a usable fashion) - for the rest, AnyEvent
		435	will simply call the callback "from time to time".
		436
		437	Example: read lines from STDIN, but only process them when the
		438	program is otherwise idle:
		439
		440	my @lines; # read data
		441	my $idle_w;
		442	my $io_w = AnyEvent->io (fh => \*STDIN, poll => 'r', cb => sub {
		443	push @lines, scalar <STDIN>;
		444
		445	# start an idle watcher, if not already done
		446	$idle_w \|\|= AnyEvent->idle (cb => sub {
		447	# handle only one line, when there are lines left
		448	if (my $line = shift @lines) {
		449	print "handled when idle: $line";
		450	} else {
		451	# otherwise disable the idle watcher again
		452	undef $idle_w;
		453	}
		454	});
		455	});
		456
371	=head2 CONDITION VARIABLES	457	=head2 CONDITION VARIABLES
372		458
373	If you are familiar with some event loops you will know that all of them	459	If you are familiar with some event loops you will know that all of them
374	require you to run some blocking "loop", "run" or similar function that	460	require you to run some blocking "loop", "run" or similar function that
375	will actively watch for new events and call your callbacks.	461	will actively watch for new events and call your callbacks.
…		…
380	The instrument to do that is called a "condition variable", so called	466	The instrument to do that is called a "condition variable", so called
381	because they represent a condition that must become true.	467	because they represent a condition that must become true.
382		468
383	Condition variables can be created by calling the C<< AnyEvent->condvar	469	Condition variables can be created by calling the C<< AnyEvent->condvar
384	>> method, usually without arguments. The only argument pair allowed is	470	>> method, usually without arguments. The only argument pair allowed is
		471
385	C<cb>, which specifies a callback to be called when the condition variable	472	C<cb>, which specifies a callback to be called when the condition variable
386	becomes true.	473	becomes true, with the condition variable as the first argument (but not
		474	the results).
387		475
388	After creation, the condition variable is "false" until it becomes "true"	476	After creation, the condition variable is "false" until it becomes "true"
389	by calling the C<send> method (or calling the condition variable as if it	477	by calling the C<send> method (or calling the condition variable as if it
390	were a callback, read about the caveats in the description for the C<<	478	were a callback, read about the caveats in the description for the C<<
391	->send >> method).	479	->send >> method).
…		…
447		535
448	my $done = AnyEvent->condvar;	536	my $done = AnyEvent->condvar;
449	my $delay = AnyEvent->timer (after => 5, cb => $done);	537	my $delay = AnyEvent->timer (after => 5, cb => $done);
450	$done->recv;	538	$done->recv;
451		539
		540	Example: Imagine an API that returns a condvar and doesn't support
		541	callbacks. This is how you make a synchronous call, for example from
		542	the main program:
		543
		544	use AnyEvent::CouchDB;
		545
		546	...
		547
		548	my @info = $couchdb->info->recv;
		549
		550	And this is how you would just ste a callback to be called whenever the
		551	results are available:
		552
		553	$couchdb->info->cb (sub {
		554	my @info = $_[0]->recv;
		555	});
		556
452	=head3 METHODS FOR PRODUCERS	557	=head3 METHODS FOR PRODUCERS
453		558
454	These methods should only be used by the producing side, i.e. the	559	These methods should only be used by the producing side, i.e. the
455	code/module that eventually sends the signal. Note that it is also	560	code/module that eventually sends the signal. Note that it is also
456	the producer side which creates the condvar in most cases, but it isn't	561	the producer side which creates the condvar in most cases, but it isn't
…		…
589	=item $bool = $cv->ready	694	=item $bool = $cv->ready
590		695
591	Returns true when the condition is "true", i.e. whether C<send> or	696	Returns true when the condition is "true", i.e. whether C<send> or
592	C<croak> have been called.	697	C<croak> have been called.
593		698
594	=item $cb = $cv->cb ([new callback])	699	=item $cb = $cv->cb ($cb->($cv))
595		700
596	This is a mutator function that returns the callback set and optionally	701	This is a mutator function that returns the callback set and optionally
597	replaces it before doing so.	702	replaces it before doing so.
598		703
599	The callback will be called when the condition becomes "true", i.e. when	704	The callback will be called when the condition becomes "true", i.e. when
…		…
789	=item L<AnyEvent::IGS>	894	=item L<AnyEvent::IGS>
790		895
791	A non-blocking interface to the Internet Go Server protocol (used by	896	A non-blocking interface to the Internet Go Server protocol (used by
792	L<App::IGS>).	897	L<App::IGS>).
793		898
794	=item L<Net::IRC3>	899	=item L<AnyEvent::IRC>
795		900
796	AnyEvent based IRC client module family.	901	AnyEvent based IRC client module family (replacing the older Net::IRC3).
797		902
798	=item L<Net::XMPP2>	903	=item L<Net::XMPP2>
799		904
800	AnyEvent based XMPP (Jabber protocol) module family.	905	AnyEvent based XMPP (Jabber protocol) module family.
801		906
…		…
821	=cut	926	=cut
822		927
823	package AnyEvent;	928	package AnyEvent;
824		929
825	no warnings;	930	no warnings;
826	use strict;	931	use strict qw(vars subs);
827		932
828	use Carp;	933	use Carp;
829		934
830	our $VERSION = 4.2;	935	our $VERSION = 4.4;
831	our $MODEL;	936	our $MODEL;
832		937
833	our $AUTOLOAD;	938	our $AUTOLOAD;
834	our @ISA;	939	our @ISA;
835		940
…		…
867	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza	972	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
868	[Wx:: => AnyEvent::Impl::POE::],	973	[Wx:: => AnyEvent::Impl::POE::],
869	[Prima:: => AnyEvent::Impl::POE::],	974	[Prima:: => AnyEvent::Impl::POE::],
870	);	975	);
871		976
872	our %method = map +($_ => 1), qw(io timer time now signal child condvar one_event DESTROY);	977	our %method = map +($_ => 1),
		978	qw(io timer time now now_update signal child idle condvar one_event DESTROY);
873		979
874	our @post_detect;	980	our @post_detect;
875		981
876	sub post_detect(&) {	982	sub post_detect(&) {
877	my ($cb) = @_;	983	my ($cb) = @_;
…		…
882	1	988	1
883	} else {	989	} else {
884	push @post_detect, $cb;	990	push @post_detect, $cb;
885		991
886	defined wantarray	992	defined wantarray
887	? bless \$cb, "AnyEvent::Util::PostDetect"	993	? bless \$cb, "AnyEvent::Util::postdetect"
888	: ()	994	: ()
889	}	995	}
890	}	996	}
891		997
892	sub AnyEvent::Util::PostDetect::DESTROY {	998	sub AnyEvent::Util::postdetect::DESTROY {
893	@post_detect = grep $_ != ${$_[0]}, @post_detect;	999	@post_detect = grep $_ != ${$_[0]}, @post_detect;
894	}	1000	}
895		1001
896	sub detect() {	1002	sub detect() {
897	unless ($MODEL) {	1003	unless ($MODEL) {
…		…
934	last;	1040	last;
935	}	1041	}
936	}	1042	}
937		1043
938	$MODEL	1044	$MODEL
939	or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.";	1045	or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.\n";
940	}	1046	}
941	}	1047	}
942		1048
943	push @{"$MODEL\::ISA"}, "AnyEvent::Base";	1049	push @{"$MODEL\::ISA"}, "AnyEvent::Base";
944		1050
945	if ($ENV{PERL_ANYEVENT_STRICT}) {
946	unshift @AnyEvent::Base::Strict::ISA, $MODEL;
947	unshift @ISA, AnyEvent::Base::Strict::
948	} else {
949	unshift @ISA, $MODEL;	1051	unshift @ISA, $MODEL;
950	}	1052
		1053	require AnyEvent::Strict if $ENV{PERL_ANYEVENT_STRICT};
951		1054
952	(shift @post_detect)->() while @post_detect;	1055	(shift @post_detect)->() while @post_detect;
953	}	1056	}
954		1057
955	$MODEL	1058	$MODEL
…		…
965		1068
966	my $class = shift;	1069	my $class = shift;
967	$class->$func (@_);	1070	$class->$func (@_);
968	}	1071	}
969		1072
		1073	# utility function to dup a filehandle. this is used by many backends
		1074	# to support binding more than one watcher per filehandle (they usually
		1075	# allow only one watcher per fd, so we dup it to get a different one).
		1076	sub _dupfh($$$$) {
		1077	my ($poll, $fh, $r, $w) = @_;
		1078
		1079	# cygwin requires the fh mode to be matching, unix doesn't
		1080	my ($rw, $mode) = $poll eq "r" ? ($r, "<")
		1081	: $poll eq "w" ? ($w, ">")
		1082	: Carp::croak "AnyEvent->io requires poll set to either 'r' or 'w'";
		1083
		1084	open my $fh2, "$mode&" . fileno $fh
		1085	or die "cannot dup() filehandle: $!,";
		1086
		1087	# we assume CLOEXEC is already set by perl in all important cases
		1088
		1089	($fh2, $rw)
		1090	}
		1091
970	package AnyEvent::Base;	1092	package AnyEvent::Base;
971		1093
972	# default implementation for now and time	1094	# default implementations for many methods
973		1095
974	use Time::HiRes ();	1096	BEGIN {
		1097	if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {
		1098	*_time = \&Time::HiRes::time;
		1099	# if (eval "use POSIX (); (POSIX::times())...
		1100	} else {
		1101	*_time = sub { time }; # epic fail
		1102	}
		1103	}
975		1104
976	sub time { Time::HiRes::time }	1105	sub time { _time }
977	sub now { Time::HiRes::time }	1106	sub now { _time }
		1107	sub now_update { }
978		1108
979	# default implementation for ->condvar	1109	# default implementation for ->condvar
980		1110
981	sub condvar {	1111	sub condvar {
982	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, AnyEvent::CondVar::	1112	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"
983	}	1113	}
984		1114
985	# default implementation for ->signal	1115	# default implementation for ->signal
986		1116
987	our %SIG_CB;	1117	our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);
		1118
		1119	sub _signal_exec {
		1120	sysread $SIGPIPE_R, my $dummy, 4;
		1121
		1122	while (%SIG_EV) {
		1123	for (keys %SIG_EV) {
		1124	delete $SIG_EV{$_};
		1125	$_->() for values %{ $SIG_CB{$_} \|\| {} };
		1126	}
		1127	}
		1128	}
988		1129
989	sub signal {	1130	sub signal {
990	my (undef, %arg) = @_;	1131	my (undef, %arg) = @_;
991		1132
		1133	unless ($SIGPIPE_R) {
		1134	require Fcntl;
		1135
		1136	if (AnyEvent::WIN32) {
		1137	require AnyEvent::Util;
		1138
		1139	($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
		1140	AnyEvent::Util::fh_nonblocking ($SIGPIPE_R) if $SIGPIPE_R;
		1141	AnyEvent::Util::fh_nonblocking ($SIGPIPE_W) if $SIGPIPE_W; # just in case
		1142	} else {
		1143	pipe $SIGPIPE_R, $SIGPIPE_W;
		1144	fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R;
		1145	fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case
		1146	}
		1147
		1148	$SIGPIPE_R
		1149	or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
		1150
		1151	# not strictly required, as $^F is normally 2, but let's make sure...
		1152	fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;
		1153	fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;
		1154
		1155	$SIG_IO = AnyEvent->io (fh => $SIGPIPE_R, poll => "r", cb => \&_signal_exec);
		1156	}
		1157
992	my $signal = uc $arg{signal}	1158	my $signal = uc $arg{signal}
993	or Carp::croak "required option 'signal' is missing";	1159	or Carp::croak "required option 'signal' is missing";
994		1160
995	$SIG_CB{$signal}{$arg{cb}} = $arg{cb};	1161	$SIG_CB{$signal}{$arg{cb}} = $arg{cb};
996	$SIG{$signal} \|\|= sub {	1162	$SIG{$signal} \|\|= sub {
997	$_->() for values %{ $SIG_CB{$signal} \|\| {} };	1163	local $!;
		1164	syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
		1165	undef $SIG_EV{$signal};
998	};	1166	};
999		1167
1000	bless [$signal, $arg{cb}], "AnyEvent::Base::Signal"	1168	bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
1001	}	1169	}
1002		1170
1003	sub AnyEvent::Base::Signal::DESTROY {	1171	sub AnyEvent::Base::signal::DESTROY {
1004	my ($signal, $cb) = @{$_[0]};	1172	my ($signal, $cb) = @{$_[0]};
1005		1173
1006	delete $SIG_CB{$signal}{$cb};	1174	delete $SIG_CB{$signal}{$cb};
1007		1175
1008	delete $SIG{$signal} unless keys %{ $SIG_CB{$signal} };	1176	delete $SIG{$signal} unless keys %{ $SIG_CB{$signal} };
…		…
1049	$CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld);	1217	$CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld);
1050	# child could be a zombie already, so make at least one round	1218	# child could be a zombie already, so make at least one round
1051	&_sigchld;	1219	&_sigchld;
1052	}	1220	}
1053		1221
1054	bless [$pid, $arg{cb}], "AnyEvent::Base::Child"	1222	bless [$pid, $arg{cb}], "AnyEvent::Base::child"
1055	}	1223	}
1056		1224
1057	sub AnyEvent::Base::Child::DESTROY {	1225	sub AnyEvent::Base::child::DESTROY {
1058	my ($pid, $cb) = @{$_[0]};	1226	my ($pid, $cb) = @{$_[0]};
1059		1227
1060	delete $PID_CB{$pid}{$cb};	1228	delete $PID_CB{$pid}{$cb};
1061	delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} };	1229	delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} };
1062		1230
1063	undef $CHLD_W unless keys %PID_CB;	1231	undef $CHLD_W unless keys %PID_CB;
		1232	}
		1233
		1234	# idle emulation is done by simply using a timer, regardless
		1235	# of whether the proces sis idle or not, and not letting
		1236	# the callback use more than 50% of the time.
		1237	sub idle {
		1238	my (undef, %arg) = @_;
		1239
		1240	my ($cb, $w, $rcb) = $arg{cb};
		1241
		1242	$rcb = sub {
		1243	if ($cb) {
		1244	$w = _time;
		1245	&$cb;
		1246	$w = _time - $w;
		1247
		1248	# never use more then 50% of the time for the idle watcher,
		1249	# within some limits
		1250	$w = 0.0001 if $w < 0.0001;
		1251	$w = 5 if $w > 5;
		1252
		1253	$w = AnyEvent->timer (after => $w, cb => $rcb);
		1254	} else {
		1255	# clean up...
		1256	undef $w;
		1257	undef $rcb;
		1258	}
		1259	};
		1260
		1261	$w = AnyEvent->timer (after => 0.05, cb => $rcb);
		1262
		1263	bless \\$cb, "AnyEvent::Base::idle"
		1264	}
		1265
		1266	sub AnyEvent::Base::idle::DESTROY {
		1267	undef $${$_[0]};
1064	}	1268	}
1065		1269
1066	package AnyEvent::CondVar;	1270	package AnyEvent::CondVar;
1067		1271
1068	our @ISA = AnyEvent::CondVar::Base::;	1272	our @ISA = AnyEvent::CondVar::Base::;
…		…
1121		1325
1122	# undocumented/compatibility with pre-3.4	1326	# undocumented/compatibility with pre-3.4
1123	*broadcast = \&send;	1327	*broadcast = \&send;
1124	*wait = \&_wait;	1328	*wait = \&_wait;
1125		1329
1126	package AnyEvent::Base::Strict;	1330	=head1 ERROR AND EXCEPTION HANDLING
1127		1331
1128	use Carp qw(croak);	1332	In general, AnyEvent does not do any error handling - it relies on the
		1333	caller to do that if required. The L<AnyEvent::Strict> module (see also
		1334	the C<PERL_ANYEVENT_STRICT> environment variable, below) provides strict
		1335	checking of all AnyEvent methods, however, which is highly useful during
		1336	development.
1129		1337
1130	# supply checks for argument validity for many functions	1338	As for exception handling (i.e. runtime errors and exceptions thrown while
		1339	executing a callback), this is not only highly event-loop specific, but
		1340	also not in any way wrapped by this module, as this is the job of the main
		1341	program.
1131		1342
1132	sub io {	1343	The pure perl event loop simply re-throws the exception (usually
1133	my $class = shift;	1344	within C<< condvar->recv >>), the L<Event> and L<EV> modules call C<<
1134	my %arg = @_;	1345	$Event/EV::DIED->() >>, L<Glib> uses C<< install_exception_handler >> and
		1346	so on.
1135		1347
1136	ref $arg{cb}	1348	=head1 ENVIRONMENT VARIABLES
1137	or croak "AnyEvent->io called with illegal cb argument '$arg{cb}'";
1138	delete $arg{cb};
1139
1140	fileno $arg{fh}
1141	or croak "AnyEvent->io called with illegal fh argument '$arg{fh}'";
1142	delete $arg{fh};
1143
1144	$arg{poll} =~ /^[rw]$/
1145	or croak "AnyEvent->io called with illegal poll argument '$arg{poll}'";
1146	delete $arg{poll};
1147
1148	croak "AnyEvent->io called with unsupported parameter(s) " . join ", ", keys %arg
1149	if keys %arg;
1150		1349
1151	$class->SUPER::io (@_)	1350	The following environment variables are used by this module or its
1152	}	1351	submodules:
1153		1352
1154	sub timer {	1353	=over 4
1155	my $class = shift;
1156	my %arg = @_;
1157		1354
1158	ref $arg{cb}	1355	=item C<PERL_ANYEVENT_VERBOSE>
1159	or croak "AnyEvent->timer called with illegal cb argument '$arg{cb}'";
1160	delete $arg{cb};
1161
1162	exists $arg{after}
1163	or croak "AnyEvent->timer called without mandatory 'after' parameter";
1164	delete $arg{after};
1165
1166	$arg{interval} > 0 \|\| !$arg{interval}
1167	or croak "AnyEvent->timer called with illegal interval argument '$arg{interval}'";
1168	delete $arg{interval};
1169
1170	croak "AnyEvent->timer called with unsupported parameter(s) " . join ", ", keys %arg
1171	if keys %arg;
1172		1356
1173	$class->SUPER::timer (@_)	1357	By default, AnyEvent will be completely silent except in fatal
1174	}	1358	conditions. You can set this environment variable to make AnyEvent more
		1359	talkative.
1175		1360
1176	sub signal {	1361	When set to C<1> or higher, causes AnyEvent to warn about unexpected
1177	my $class = shift;	1362	conditions, such as not being able to load the event model specified by
1178	my %arg = @_;	1363	C<PERL_ANYEVENT_MODEL>.
1179		1364
1180	ref $arg{cb}	1365	When set to C<2> or higher, cause AnyEvent to report to STDERR which event
1181	or croak "AnyEvent->signal called with illegal cb argument '$arg{cb}'";	1366	model it chooses.
1182	delete $arg{cb};
1183
1184	eval "require POSIX; defined &POSIX::SIG$arg{signal}"
1185	or croak "AnyEvent->signal called with illegal signal name '$arg{signal}'";
1186	delete $arg{signal};
1187
1188	croak "AnyEvent->signal called with unsupported parameter(s) " . join ", ", keys %arg
1189	if keys %arg;
1190		1367
1191	$class->SUPER::signal (@_)	1368	=item C<PERL_ANYEVENT_STRICT>
1192	}
1193		1369
1194	sub child {	1370	AnyEvent does not do much argument checking by default, as thorough
1195	my $class = shift;	1371	argument checking is very costly. Setting this variable to a true value
1196	my %arg = @_;	1372	will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly
		1373	check the arguments passed to most method calls. If it finds any problems
		1374	it will croak.
1197		1375
1198	ref $arg{cb}	1376	In other words, enables "strict" mode.
1199	or croak "AnyEvent->signal called with illegal cb argument '$arg{cb}'";
1200	delete $arg{cb};
1201
1202	$arg{pid} =~ /^-?\d+$/
1203	or croak "AnyEvent->signal called with illegal pid value '$arg{pid}'";
1204	delete $arg{pid};
1205
1206	croak "AnyEvent->signal called with unsupported parameter(s) " . join ", ", keys %arg
1207	if keys %arg;
1208		1377
1209	$class->SUPER::child (@_)	1378	Unlike C<use strict>, it is definitely recommended ot keep it off in
1210	}	1379	production. Keeping C<PERL_ANYEVENT_STRICT=1> in your environment while
		1380	developing programs can be very useful, however.
1211		1381
1212	sub condvar {	1382	=item C<PERL_ANYEVENT_MODEL>
1213	my $class = shift;
1214	my %arg = @_;
1215		1383
1216	!exists $arg{cb} or ref $arg{cb}	1384	This can be used to specify the event model to be used by AnyEvent, before
1217	or croak "AnyEvent->condvar called with illegal cb argument '$arg{cb}'";	1385	auto detection and -probing kicks in. It must be a string consisting
1218	delete $arg{cb};	1386	entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended
1219		1387	and the resulting module name is loaded and if the load was successful,
1220	croak "AnyEvent->condvar called with unsupported parameter(s) " . join ", ", keys %arg	1388	used as event model. If it fails to load AnyEvent will proceed with
1221	if keys %arg;	1389	auto detection and -probing.
1222		1390
1223	$class->SUPER::condvar (@_)	1391	This functionality might change in future versions.
1224	}
1225		1392
1226	sub time {	1393	For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you
1227	my $class = shift;	1394	could start your program like this:
1228		1395
1229	@_	1396	PERL_ANYEVENT_MODEL=Perl perl ...
1230	and croak "AnyEvent->time wrongly called with paramaters";
1231		1397
1232	$class->SUPER::time (@_)	1398	=item C<PERL_ANYEVENT_PROTOCOLS>
1233	}
1234		1399
1235	sub now {	1400	Used by both L<AnyEvent::DNS> and L<AnyEvent::Socket> to determine preferences
1236	my $class = shift;	1401	for IPv4 or IPv6. The default is unspecified (and might change, or be the result
		1402	of auto probing).
1237		1403
1238	@_	1404	Must be set to a comma-separated list of protocols or address families,
1239	and croak "AnyEvent->now wrongly called with paramaters";	1405	current supported: C<ipv4> and C<ipv6>. Only protocols mentioned will be
		1406	used, and preference will be given to protocols mentioned earlier in the
		1407	list.
1240		1408
1241	$class->SUPER::now (@_)	1409	This variable can effectively be used for denial-of-service attacks
1242	}	1410	against local programs (e.g. when setuid), although the impact is likely
		1411	small, as the program has to handle conenction and other failures anyways.
		1412
		1413	Examples: C<PERL_ANYEVENT_PROTOCOLS=ipv4,ipv6> - prefer IPv4 over IPv6,
		1414	but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4>
		1415	- only support IPv4, never try to resolve or contact IPv6
		1416	addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or
		1417	IPv6, but prefer IPv6 over IPv4.
		1418
		1419	=item C<PERL_ANYEVENT_EDNS0>
		1420
		1421	Used by L<AnyEvent::DNS> to decide whether to use the EDNS0 extension
		1422	for DNS. This extension is generally useful to reduce DNS traffic, but
		1423	some (broken) firewalls drop such DNS packets, which is why it is off by
		1424	default.
		1425
		1426	Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce
		1427	EDNS0 in its DNS requests.
		1428
		1429	=item C<PERL_ANYEVENT_MAX_FORKS>
		1430
		1431	The maximum number of child processes that C<AnyEvent::Util::fork_call>
		1432	will create in parallel.
		1433
		1434	=back
1243		1435
1244	=head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE	1436	=head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE
1245		1437
1246	This is an advanced topic that you do not normally need to use AnyEvent in	1438	This is an advanced topic that you do not normally need to use AnyEvent in
1247	a module. This section is only of use to event loop authors who want to	1439	a module. This section is only of use to event loop authors who want to
…		…
1281		1473
1282	I<rxvt-unicode> also cheats a bit by not providing blocking access to	1474	I<rxvt-unicode> also cheats a bit by not providing blocking access to
1283	condition variables: code blocking while waiting for a condition will	1475	condition variables: code blocking while waiting for a condition will
1284	C<die>. This still works with most modules/usages, and blocking calls must	1476	C<die>. This still works with most modules/usages, and blocking calls must
1285	not be done in an interactive application, so it makes sense.	1477	not be done in an interactive application, so it makes sense.
1286
1287	=head1 ENVIRONMENT VARIABLES
1288
1289	The following environment variables are used by this module:
1290
1291	=over 4
1292
1293	=item C<PERL_ANYEVENT_VERBOSE>
1294
1295	By default, AnyEvent will be completely silent except in fatal
1296	conditions. You can set this environment variable to make AnyEvent more
1297	talkative.
1298
1299	When set to C<1> or higher, causes AnyEvent to warn about unexpected
1300	conditions, such as not being able to load the event model specified by
1301	C<PERL_ANYEVENT_MODEL>.
1302
1303	When set to C<2> or higher, cause AnyEvent to report to STDERR which event
1304	model it chooses.
1305
1306	=item C<PERL_ANYEVENT_STRICT>
1307
1308	AnyEvent does not do much argument checking by default, as thorough
1309	argument checking is very costly. Setting this variable to a true value
1310	will cause AnyEvent to thoroughly check the arguments passed to most
1311	method calls and croaks if it finds any problems. In other words, enables
1312	"strict" mode. Unlike C<use strict> it is definitely recommended ot keep
1313	it off in production.
1314
1315	=item C<PERL_ANYEVENT_MODEL>
1316
1317	This can be used to specify the event model to be used by AnyEvent, before
1318	auto detection and -probing kicks in. It must be a string consisting
1319	entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended
1320	and the resulting module name is loaded and if the load was successful,
1321	used as event model. If it fails to load AnyEvent will proceed with
1322	auto detection and -probing.
1323
1324	This functionality might change in future versions.
1325
1326	For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you
1327	could start your program like this:
1328
1329	PERL_ANYEVENT_MODEL=Perl perl ...
1330
1331	=item C<PERL_ANYEVENT_PROTOCOLS>
1332
1333	Used by both L<AnyEvent::DNS> and L<AnyEvent::Socket> to determine preferences
1334	for IPv4 or IPv6. The default is unspecified (and might change, or be the result
1335	of auto probing).
1336
1337	Must be set to a comma-separated list of protocols or address families,
1338	current supported: C<ipv4> and C<ipv6>. Only protocols mentioned will be
1339	used, and preference will be given to protocols mentioned earlier in the
1340	list.
1341
1342	This variable can effectively be used for denial-of-service attacks
1343	against local programs (e.g. when setuid), although the impact is likely
1344	small, as the program has to handle connection errors already-
1345
1346	Examples: C<PERL_ANYEVENT_PROTOCOLS=ipv4,ipv6> - prefer IPv4 over IPv6,
1347	but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4>
1348	- only support IPv4, never try to resolve or contact IPv6
1349	addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or
1350	IPv6, but prefer IPv6 over IPv4.
1351
1352	=item C<PERL_ANYEVENT_EDNS0>
1353
1354	Used by L<AnyEvent::DNS> to decide whether to use the EDNS0 extension
1355	for DNS. This extension is generally useful to reduce DNS traffic, but
1356	some (broken) firewalls drop such DNS packets, which is why it is off by
1357	default.
1358
1359	Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce
1360	EDNS0 in its DNS requests.
1361
1362	=item C<PERL_ANYEVENT_MAX_FORKS>
1363
1364	The maximum number of child processes that C<AnyEvent::Util::fork_call>
1365	will create in parallel.
1366
1367	=back
1368		1478
1369	=head1 EXAMPLE PROGRAM	1479	=head1 EXAMPLE PROGRAM
1370		1480
1371	The following program uses an I/O watcher to read data from STDIN, a timer	1481	The following program uses an I/O watcher to read data from STDIN, a timer
1372	to display a message once per second, and a condition variable to quit the	1482	to display a message once per second, and a condition variable to quit the
…		…
1566	watcher.	1676	watcher.
1567		1677
1568	=head3 Results	1678	=head3 Results
1569		1679
1570	name watchers bytes create invoke destroy comment	1680	name watchers bytes create invoke destroy comment
1571	EV/EV 400000 244 0.56 0.46 0.31 EV native interface	1681	EV/EV 400000 224 0.47 0.35 0.27 EV native interface
1572	EV/Any 100000 244 2.50 0.46 0.29 EV + AnyEvent watchers	1682	EV/Any 100000 224 2.88 0.34 0.27 EV + AnyEvent watchers
1573	CoroEV/Any 100000 244 2.49 0.44 0.29 coroutines + Coro::Signal	1683	CoroEV/Any 100000 224 2.85 0.35 0.28 coroutines + Coro::Signal
1574	Perl/Any 100000 513 4.92 0.87 1.12 pure perl implementation	1684	Perl/Any 100000 452 4.13 0.73 0.95 pure perl implementation
1575	Event/Event 16000 516 31.88 31.30 0.85 Event native interface	1685	Event/Event 16000 517 32.20 31.80 0.81 Event native interface
1576	Event/Any 16000 590 35.75 31.42 1.08 Event + AnyEvent watchers	1686	Event/Any 16000 590 35.85 31.55 1.06 Event + AnyEvent watchers
1577	Glib/Any 16000 1357 98.22 12.41 54.00 quadratic behaviour	1687	Glib/Any 16000 1357 102.33 12.31 51.00 quadratic behaviour
1578	Tk/Any 2000 1860 26.97 67.98 14.00 SEGV with >> 2000 watchers	1688	Tk/Any 2000 1860 27.20 66.31 14.00 SEGV with >> 2000 watchers
1579	POE/Event 2000 6644 108.64 736.02 14.73 via POE::Loop::Event	1689	POE/Event 2000 6328 109.99 751.67 14.02 via POE::Loop::Event
1580	POE/Select 2000 6343 94.13 809.12 565.96 via POE::Loop::Select	1690	POE/Select 2000 6027 94.54 809.13 579.80 via POE::Loop::Select
1581		1691
1582	=head3 Discussion	1692	=head3 Discussion
1583		1693
1584	The benchmark does I<not> measure scalability of the event loop very	1694	The benchmark does I<not> measure scalability of the event loop very
1585	well. For example, a select-based event loop (such as the pure perl one)	1695	well. For example, a select-based event loop (such as the pure perl one)
…		…
1787	watchers, as the management overhead dominates.	1897	watchers, as the management overhead dominates.
1788		1898
1789	=back	1899	=back
1790		1900
1791		1901
		1902	=head1 SIGNALS
		1903
		1904	AnyEvent currently installs handlers for these signals:
		1905
		1906	=over 4
		1907
		1908	=item SIGCHLD
		1909
		1910	A handler for C<SIGCHLD> is installed by AnyEvent's child watcher
		1911	emulation for event loops that do not support them natively. Also, some
		1912	event loops install a similar handler.
		1913
		1914	=item SIGPIPE
		1915
		1916	A no-op handler is installed for C<SIGPIPE> when C<$SIG{PIPE}> is C<undef>
		1917	when AnyEvent gets loaded.
		1918
		1919	The rationale for this is that AnyEvent users usually do not really depend
		1920	on SIGPIPE delivery (which is purely an optimisation for shell use, or
		1921	badly-written programs), but C<SIGPIPE> can cause spurious and rare
		1922	program exits as a lot of people do not expect C<SIGPIPE> when writing to
		1923	some random socket.
		1924
		1925	The rationale for installing a no-op handler as opposed to ignoring it is
		1926	that this way, the handler will be restored to defaults on exec.
		1927
		1928	Feel free to install your own handler, or reset it to defaults.
		1929
		1930	=back
		1931
		1932	=cut
		1933
		1934	$SIG{PIPE} = sub { }
		1935	unless defined $SIG{PIPE};
		1936
		1937
1792	=head1 FORK	1938	=head1 FORK
1793		1939
1794	Most event libraries are not fork-safe. The ones who are usually are	1940	Most event libraries are not fork-safe. The ones who are usually are
1795	because they rely on inefficient but fork-safe C<select> or C<poll>	1941	because they rely on inefficient but fork-safe C<select> or C<poll>
1796	calls. Only L<EV> is fully fork-aware.	1942	calls. Only L<EV> is fully fork-aware.
…		…
1824	=head1 BUGS	1970	=head1 BUGS
1825		1971
1826	Perl 5.8 has numerous memleaks that sometimes hit this module and are hard	1972	Perl 5.8 has numerous memleaks that sometimes hit this module and are hard
1827	to work around. If you suffer from memleaks, first upgrade to Perl 5.10	1973	to work around. If you suffer from memleaks, first upgrade to Perl 5.10
1828	and check wether the leaks still show up. (Perl 5.10.0 has other annoying	1974	and check wether the leaks still show up. (Perl 5.10.0 has other annoying
1829	mamleaks, such as leaking on C<map> and C<grep> but it is usually not as	1975	memleaks, such as leaking on C<map> and C<grep> but it is usually not as
1830	pronounced).	1976	pronounced).
1831		1977
1832		1978
1833	=head1 SEE ALSO	1979	=head1 SEE ALSO
1834		1980

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Comparing AnyEvent/lib/AnyEvent.pm (file contents): Revision 1.167 by root, Tue Jul 8 23:44:51 2008 UTC vs. Revision 1.208 by root, Sun Apr 26 18:12:53 2009 UTC

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Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.167 by root, Tue Jul 8 23:44:51 2008 UTC vs.
Revision 1.208 by root, Sun Apr 26 18:12:53 2009 UTC