[ViewVC] Diff of: cvs/Coro/Coro.pm

Comparing Coro/Coro.pm (file contents):
Revision 1.108 by root, Fri Jan 5 20:00:49 2007 UTC vs.
Revision 1.145 by root, Wed Oct 3 16:03:17 2007 UTC

…		…
20		20
21	=head1 DESCRIPTION	21	=head1 DESCRIPTION
22		22
23	This module collection manages coroutines. Coroutines are similar	23	This module collection manages coroutines. Coroutines are similar
24	to threads but don't run in parallel at the same time even on SMP	24	to threads but don't run in parallel at the same time even on SMP
25	machines. The specific flavor of coroutine use din this module also	25	machines. The specific flavor of coroutine used in this module also
26	guarentees you that it will not switch between coroutines unless	26	guarantees you that it will not switch between coroutines unless
27	necessary, at easily-identified points in your program, so locking and	27	necessary, at easily-identified points in your program, so locking and
28	parallel access are rarely an issue, making coroutine programming much	28	parallel access are rarely an issue, making coroutine programming much
29	safer than threads programming.	29	safer than threads programming.
30		30
31	(Perl, however, does not natively support real threads but instead does a	31	(Perl, however, does not natively support real threads but instead does a
…		…
50		50
51	our $idle; # idle handler	51	our $idle; # idle handler
52	our $main; # main coroutine	52	our $main; # main coroutine
53	our $current; # current coroutine	53	our $current; # current coroutine
54		54
55	our $VERSION = '3.3';	55	our $VERSION = '4.0';
56		56
57	our @EXPORT = qw(async async_pool cede schedule terminate current unblock_sub);	57	our @EXPORT = qw(async async_pool cede schedule terminate current unblock_sub);
58	our %EXPORT_TAGS = (	58	our %EXPORT_TAGS = (
59	prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],	59	prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],
60	);	60	);
…		…
108		108
109	The current coroutine (the last coroutine switched to). The initial value	109	The current coroutine (the last coroutine switched to). The initial value
110	is C<$main> (of course).	110	is C<$main> (of course).
111		111
112	This variable is B<strictly> I<read-only>. It is provided for performance	112	This variable is B<strictly> I<read-only>. It is provided for performance
113	reasons. If performance is not essentiel you are encouraged to use the	113	reasons. If performance is not essential you are encouraged to use the
114	C<Coro::current> function instead.	114	C<Coro::current> function instead.
115		115
116	=cut	116	=cut
117		117
		118	$main->{desc} = "[main::]";
		119
118	# maybe some other module used Coro::Specific before...	120	# maybe some other module used Coro::Specific before...
119	$main->{specific} = $current->{specific}	121	$main->{_specific} = $current->{_specific}
120	if $current;	122	if $current;
121		123
122	_set_current $main;	124	_set_current $main;
123		125
124	sub current() { $current }	126	sub current() { $current }
…		…
149	# free coroutine data and mark as destructed	151	# free coroutine data and mark as destructed
150	$self->_destroy	152	$self->_destroy
151	or return;	153	or return;
152		154
153	# call all destruction callbacks	155	# call all destruction callbacks
154	$_->(@{$self->{status}})	156	$_->(@{$self->{_status}})
155	for @{(delete $self->{destroy_cb}) \|\| []};	157	for @{(delete $self->{_on_destroy}) \|\| []};
156	}	158	}
157		159
158	# this coroutine is necessary because a coroutine	160	# this coroutine is necessary because a coroutine
159	# cannot destroy itself.	161	# cannot destroy itself.
160	my @destroy;	162	my @destroy;
…		…
166	while @destroy;	168	while @destroy;
167		169
168	&schedule;	170	&schedule;
169	}	171	}
170	};	172	};
171		173	$manager->desc ("[coro manager]");
172	$manager->prio (PRIO_MAX);	174	$manager->prio (PRIO_MAX);
173		175
174	# static methods. not really.	176	# static methods. not really.
175		177
176	=back	178	=back
…		…
185		187
186	Create a new asynchronous coroutine and return it's coroutine object	188	Create a new asynchronous coroutine and return it's coroutine object
187	(usually unused). When the sub returns the new coroutine is automatically	189	(usually unused). When the sub returns the new coroutine is automatically
188	terminated.	190	terminated.
189		191
190	Calling C<exit> in a coroutine will not work correctly, so do not do that.	192	See the C<Coro::State::new> constructor for info about the coroutine
		193	environment.
191		194
192	When the coroutine dies, the program will exit, just as in the main	195	Calling C<exit> in a coroutine will do the same as calling exit outside
193	program.	196	the coroutine. Likewise, when the coroutine dies, the program will exit,
		197	just as it would in the main program.
194		198
195	# create a new coroutine that just prints its arguments	199	# create a new coroutine that just prints its arguments
196	async {	200	async {
197	print "@_\n";	201	print "@_\n";
198	} 1,2,3,4;	202	} 1,2,3,4;
…		…
223	The pool size is limited to 8 idle coroutines (this can be adjusted by	227	The pool size is limited to 8 idle coroutines (this can be adjusted by
224	changing $Coro::POOL_SIZE), and there can be as many non-idle coros as	228	changing $Coro::POOL_SIZE), and there can be as many non-idle coros as
225	required.	229	required.
226		230
227	If you are concerned about pooled coroutines growing a lot because a	231	If you are concerned about pooled coroutines growing a lot because a
228	single C<async_pool> used a lot of stackspace you can e.g. C<async_pool {	232	single C<async_pool> used a lot of stackspace you can e.g. C<async_pool
229	terminate }> once per second or so to slowly replenish the pool.	233	{ terminate }> once per second or so to slowly replenish the pool. In
		234	addition to that, when the stacks used by a handler grows larger than 16kb
		235	(adjustable with $Coro::POOL_RSS) it will also exit.
230		236
231	=cut	237	=cut
232		238
233	our $POOL_SIZE = 8;	239	our $POOL_SIZE = 8;
		240	our $POOL_RSS = 16 * 1024;
234	our @pool;	241	our @async_pool;
235		242
236	sub pool_handler {	243	sub pool_handler {
		244	my $cb;
		245
237	while () {	246	while () {
238	my ($cb, @arg) = @{ delete $current->{_invoke} };
239
240	eval {	247	eval {
241	$cb->(@arg);	248	while () {
		249	_pool_1 $cb;
		250	&$cb;
		251	_pool_2 $cb;
		252	&schedule;
		253	}
242	};	254	};
		255
		256	last if $@ eq "\3terminate\2\n";
243	warn $@ if $@;	257	warn $@ if $@;
244
245	last if @pool >= $POOL_SIZE;
246	push @pool, $current;
247
248	$current->prio (0);
249	schedule;
250	}	258	}
251	}	259	}
252		260
253	sub async_pool(&@) {	261	sub async_pool(&@) {
254	# this is also inlined into the unlock_scheduler	262	# this is also inlined into the unlock_scheduler
255	my $coro = (pop @pool or new Coro \&pool_handler);	263	my $coro = (pop @async_pool) \|\| new Coro \&pool_handler;
256		264
257	$coro->{_invoke} = [@_];	265	$coro->{_invoke} = [@_];
258	$coro->ready;	266	$coro->ready;
259		267
260	$coro	268	$coro
…		…
278	# wake up sleeping coroutine	286	# wake up sleeping coroutine
279	$current->ready;	287	$current->ready;
280	undef $current;	288	undef $current;
281	};	289	};
282		290
283	# call schedule until event occured.	291	# call schedule until event occurred.
284	# in case we are woken up for other reasons	292	# in case we are woken up for other reasons
285	# (current still defined), loop.	293	# (current still defined), loop.
286	Coro::schedule while $current;	294	Coro::schedule while $current;
287	}	295	}
288		296
…		…
303		311
304	=item terminate [arg...]	312	=item terminate [arg...]
305		313
306	Terminates the current coroutine with the given status values (see L<cancel>).	314	Terminates the current coroutine with the given status values (see L<cancel>).
307		315
		316	=item killall
		317
		318	Kills/terminates/cancels all coroutines except the currently running
		319	one. This is useful after a fork, either in the child or the parent, as
		320	usually only one of them should inherit the running coroutines.
		321
308	=cut	322	=cut
309		323
310	sub terminate {	324	sub terminate {
311	$current->cancel (@_);	325	$current->cancel (@_);
		326	}
		327
		328	sub killall {
		329	for (Coro::State::list) {
		330	$_->cancel
		331	if $_ != $current && UNIVERSAL::isa $_, "Coro";
		332	}
312	}	333	}
313		334
314	=back	335	=back
315		336
316	# dynamic methods	337	# dynamic methods
…		…
326	Create a new coroutine and return it. When the sub returns the coroutine	347	Create a new coroutine and return it. When the sub returns the coroutine
327	automatically terminates as if C<terminate> with the returned values were	348	automatically terminates as if C<terminate> with the returned values were
328	called. To make the coroutine run you must first put it into the ready queue	349	called. To make the coroutine run you must first put it into the ready queue
329	by calling the ready method.	350	by calling the ready method.
330		351
331	Calling C<exit> in a coroutine will not work correctly, so do not do that.	352	See C<async> and C<Coro::State::new> for additional info about the
		353	coroutine environment.
332		354
333	=cut	355	=cut
334		356
335	sub _run_coro {	357	sub _run_coro {
336	terminate &{+shift};	358	terminate &{+shift};
…		…
360		382
361	=cut	383	=cut
362		384
363	sub cancel {	385	sub cancel {
364	my $self = shift;	386	my $self = shift;
365	$self->{status} = [@_];	387	$self->{_status} = [@_];
366		388
367	if ($current == $self) {	389	if ($current == $self) {
368	push @destroy, $self;	390	push @destroy, $self;
369	$manager->ready;	391	$manager->ready;
370	&schedule while 1;	392	&schedule while 1;
…		…
374	}	396	}
375		397
376	=item $coroutine->join	398	=item $coroutine->join
377		399
378	Wait until the coroutine terminates and return any values given to the	400	Wait until the coroutine terminates and return any values given to the
379	C<terminate> or C<cancel> functions. C<join> can be called multiple times	401	C<terminate> or C<cancel> functions. C<join> can be called concurrently
380	from multiple coroutine.	402	from multiple coroutines.
381		403
382	=cut	404	=cut
383		405
384	sub join {	406	sub join {
385	my $self = shift;	407	my $self = shift;
386		408
387	unless ($self->{status}) {	409	unless ($self->{_status}) {
388	my $current = $current;	410	my $current = $current;
389		411
390	push @{$self->{destroy_cb}}, sub {	412	push @{$self->{_on_destroy}}, sub {
391	$current->ready;	413	$current->ready;
392	undef $current;	414	undef $current;
393	};	415	};
394		416
395	&schedule while $current;	417	&schedule while $current;
396	}	418	}
397		419
398	wantarray ? @{$self->{status}} : $self->{status}[0];	420	wantarray ? @{$self->{_status}} : $self->{_status}[0];
399	}	421	}
400		422
401	=item $coroutine->on_destroy (\&cb)	423	=item $coroutine->on_destroy (\&cb)
402		424
403	Registers a callback that is called when this coroutine gets destroyed,	425	Registers a callback that is called when this coroutine gets destroyed,
…		…
407	=cut	429	=cut
408		430
409	sub on_destroy {	431	sub on_destroy {
410	my ($self, $cb) = @_;	432	my ($self, $cb) = @_;
411		433
412	push @{ $self->{destroy_cb} }, $cb;	434	push @{ $self->{_on_destroy} }, $cb;
413	}	435	}
414		436
415	=item $oldprio = $coroutine->prio ($newprio)	437	=item $oldprio = $coroutine->prio ($newprio)
416		438
417	Sets (or gets, if the argument is missing) the priority of the	439	Sets (or gets, if the argument is missing) the priority of the
…		…
442	=item $olddesc = $coroutine->desc ($newdesc)	464	=item $olddesc = $coroutine->desc ($newdesc)
443		465
444	Sets (or gets in case the argument is missing) the description for this	466	Sets (or gets in case the argument is missing) the description for this
445	coroutine. This is just a free-form string you can associate with a coroutine.	467	coroutine. This is just a free-form string you can associate with a coroutine.
446		468
		469	This method simply sets the C<< $coroutine->{desc} >> member to the given string. You
		470	can modify this member directly if you wish.
		471
447	=cut	472	=cut
448		473
449	sub desc {	474	sub desc {
450	my $old = $_[0]{desc};	475	my $old = $_[0]{desc};
451	$_[0]{desc} = $_[1] if @_ > 1;	476	$_[0]{desc} = $_[1] if @_ > 1;
…		…
459	=over 4	484	=over 4
460		485
461	=item Coro::nready	486	=item Coro::nready
462		487
463	Returns the number of coroutines that are currently in the ready state,	488	Returns the number of coroutines that are currently in the ready state,
464	i.e. that can be swicthed to. The value C<0> means that the only runnable	489	i.e. that can be switched to. The value C<0> means that the only runnable
465	coroutine is the currently running one, so C<cede> would have no effect,	490	coroutine is the currently running one, so C<cede> would have no effect,
466	and C<schedule> would cause a deadlock unless there is an idle handler	491	and C<schedule> would cause a deadlock unless there is an idle handler
467	that wakes up some coroutines.	492	that wakes up some coroutines.
468		493
469	=item my $guard = Coro::guard { ... }	494	=item my $guard = Coro::guard { ... }
470		495
471	This creates and returns a guard object. Nothing happens until the objetc	496	This creates and returns a guard object. Nothing happens until the object
472	gets destroyed, in which case the codeblock given as argument will be	497	gets destroyed, in which case the codeblock given as argument will be
473	executed. This is useful to free locks or other resources in case of a	498	executed. This is useful to free locks or other resources in case of a
474	runtime error or when the coroutine gets canceled, as in both cases the	499	runtime error or when the coroutine gets canceled, as in both cases the
475	guard block will be executed. The guard object supports only one method,	500	guard block will be executed. The guard object supports only one method,
476	C<< ->cancel >>, which will keep the codeblock from being executed.	501	C<< ->cancel >>, which will keep the codeblock from being executed.
…		…
505	This utility function takes a BLOCK or code reference and "unblocks" it,	530	This utility function takes a BLOCK or code reference and "unblocks" it,
506	returning the new coderef. This means that the new coderef will return	531	returning the new coderef. This means that the new coderef will return
507	immediately without blocking, returning nothing, while the original code	532	immediately without blocking, returning nothing, while the original code
508	ref will be called (with parameters) from within its own coroutine.	533	ref will be called (with parameters) from within its own coroutine.
509		534
510	The reason this fucntion exists is that many event libraries (such as the	535	The reason this function exists is that many event libraries (such as the
511	venerable L<Event\|Event> module) are not coroutine-safe (a weaker form	536	venerable L<Event\|Event> module) are not coroutine-safe (a weaker form
512	of thread-safety). This means you must not block within event callbacks,	537	of thread-safety). This means you must not block within event callbacks,
513	otherwise you might suffer from crashes or worse.	538	otherwise you might suffer from crashes or worse.
514		539
515	This function allows your callbacks to block by executing them in another	540	This function allows your callbacks to block by executing them in another
…		…
526		551
527	# we create a special coro because we want to cede,	552	# we create a special coro because we want to cede,
528	# to reduce pressure on the coro pool (because most callbacks	553	# to reduce pressure on the coro pool (because most callbacks
529	# return immediately and can be reused) and because we cannot cede	554	# return immediately and can be reused) and because we cannot cede
530	# inside an event callback.	555	# inside an event callback.
531	our $unblock_scheduler = async {	556	our $unblock_scheduler = new Coro sub {
532	while () {	557	while () {
533	while (my $cb = pop @unblock_queue) {	558	while (my $cb = pop @unblock_queue) {
534	# this is an inlined copy of async_pool	559	# this is an inlined copy of async_pool
535	my $coro = (pop @pool or new Coro \&pool_handler);	560	my $coro = (pop @async_pool) \|\| new Coro \&pool_handler;
536		561
537	$coro->{_invoke} = $cb;	562	$coro->{_invoke} = $cb;
538	$coro->ready;	563	$coro->ready;
539	cede; # for short-lived callbacks, this reduces pressure on the coro pool	564	cede; # for short-lived callbacks, this reduces pressure on the coro pool
540	}	565	}
541	schedule; # sleep well	566	schedule; # sleep well
542	}	567	}
543	};	568	};
		569	$unblock_scheduler->desc ("[unblock_sub scheduler]");
544		570
545	sub unblock_sub(&) {	571	sub unblock_sub(&) {
546	my $cb = shift;	572	my $cb = shift;
547		573
548	sub {	574	sub {
…		…
561		587
562	- you must make very sure that no coro is still active on global	588	- you must make very sure that no coro is still active on global
563	destruction. very bad things might happen otherwise (usually segfaults).	589	destruction. very bad things might happen otherwise (usually segfaults).
564		590
565	- this module is not thread-safe. You should only ever use this module	591	- this module is not thread-safe. You should only ever use this module
566	from the same thread (this requirement might be losened in the future	592	from the same thread (this requirement might be loosened in the future
567	to allow per-thread schedulers, but Coro::State does not yet allow	593	to allow per-thread schedulers, but Coro::State does not yet allow
568	this).	594	this).
569		595
570	=head1 SEE ALSO	596	=head1 SEE ALSO
571		597

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Comparing Coro/Coro.pm (file contents): Revision 1.108 by root, Fri Jan 5 20:00:49 2007 UTC vs. Revision 1.145 by root, Wed Oct 3 16:03:17 2007 UTC

Diff Legend

Comparing Coro/Coro.pm (file contents):
Revision 1.108 by root, Fri Jan 5 20:00:49 2007 UTC vs.
Revision 1.145 by root, Wed Oct 3 16:03:17 2007 UTC