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

Comparing Coro/Coro.pm (file contents):
Revision 1.24 by root, Wed Jul 25 04:14:37 2001 UTC vs.
Revision 1.57 by pcg, Sun Nov 30 22:49:25 2003 UTC

…		…
19	cede;	19	cede;
20		20
21	=head1 DESCRIPTION	21	=head1 DESCRIPTION
22		22
23	This module collection manages coroutines. Coroutines are similar to	23	This module collection manages coroutines. Coroutines are similar to
24	Threads but don't run in parallel.	24	threads but don't run in parallel.
25
26	This module is still experimental, see the BUGS section below.
27		25
28	In this module, coroutines are defined as "callchain + lexical variables	26	In this module, coroutines are defined as "callchain + lexical variables
29	+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own	27	+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
30	callchain, it's own set of lexicals and it's own set of perl's most	28	callchain, it's own set of lexicals and it's own set of perl's most
31	important global variables.	29	important global variables.
32		30
33	=cut	31	=cut
34		32
35	package Coro;	33	package Coro;
36		34
		35	BEGIN { eval { require warnings } && warnings->unimport ("uninitialized") }
		36
37	use Coro::State;	37	use Coro::State;
38		38
		39	use vars qw($idle $main $current);
		40
39	use base Exporter;	41	use base Exporter;
40		42
41	$VERSION = 0.12;	43	$VERSION = "0.9";
42		44
43	@EXPORT = qw(async cede schedule terminate current);	45	@EXPORT = qw(async cede schedule terminate current);
44	@EXPORT_OK = qw($current);	46	%EXPORT_TAGS = (
		47	prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],
		48	);
		49	@EXPORT_OK = @{$EXPORT_TAGS{prio}};
45		50
46	{	51	{
47	my @async;	52	my @async;
		53	my $init;
48		54
49	# this way of handling attributes simply is NOT scalable ;()	55	# this way of handling attributes simply is NOT scalable ;()
50	sub import {	56	sub import {
51	Coro->export_to_level(1, @_);	57	Coro->export_to_level(1, @_);
52	my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};	58	my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
…		…
54	my ($package, $ref) = (shift, shift);	60	my ($package, $ref) = (shift, shift);
55	my @attrs;	61	my @attrs;
56	for (@_) {	62	for (@_) {
57	if ($_ eq "Coro") {	63	if ($_ eq "Coro") {
58	push @async, $ref;	64	push @async, $ref;
		65	unless ($init++) {
		66	eval q{
		67	sub INIT {
		68	&async(pop @async) while @async;
		69	}
		70	};
		71	}
59	} else {	72	} else {
60	push @attrs, $_;	73	push @attrs, $_;
61	}	74	}
62	}	75	}
63	return $old ? $old->($package, $ref, @attrs) : @attrs;	76	return $old ? $old->($package, $ref, @attrs) : @attrs;
64	};	77	};
65	}	78	}
66		79
67	sub INIT {
68	&async(pop @async) while @async;
69	}
70	}	80	}
		81
		82	=over 4
71		83
72	=item $main	84	=item $main
73		85
74	This coroutine represents the main program.	86	This coroutine represents the main program.
75		87
76	=cut	88	=cut
77		89
78	our $main = new Coro;	90	$main = new Coro;
79		91
80	=item $current (or as function: current)	92	=item $current (or as function: current)
81		93
82	The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).	94	The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
83		95
…		…
86	# maybe some other module used Coro::Specific before...	98	# maybe some other module used Coro::Specific before...
87	if ($current) {	99	if ($current) {
88	$main->{specific} = $current->{specific};	100	$main->{specific} = $current->{specific};
89	}	101	}
90		102
91	our $current = $main;	103	$current = $main;
92		104
93	sub current() { $current }	105	sub current() { $current }
94		106
95	=item $idle	107	=item $idle
96		108
…		…
98	implementation prints "FATAL: deadlock detected" and exits.	110	implementation prints "FATAL: deadlock detected" and exits.
99		111
100	=cut	112	=cut
101		113
102	# should be done using priorities :(	114	# should be done using priorities :(
103	our $idle = new Coro sub {	115	$idle = new Coro sub {
104	print STDERR "FATAL: deadlock detected\n";	116	print STDERR "FATAL: deadlock detected\n";
105	exit(51);	117	exit(51);
106	};	118	};
107		119
108	# this coroutine is necessary because a coroutine	120	# this coroutine is necessary because a coroutine
109	# cannot destroy itself.	121	# cannot destroy itself.
110	my @destroy;	122	my @destroy;
		123	my $manager;
111	my $manager = new Coro sub {	124	$manager = new Coro sub {
112	while() {	125	while () {
113	delete ((pop @destroy)->{_coro_state}) while @destroy;	126	# by overwriting the state object with the manager we destroy it
		127	# while still being able to schedule this coroutine (in case it has
		128	# been readied multiple times. this is harmless since the manager
		129	# can be called as many times as neccessary and will always
		130	# remove itself from the runqueue
		131	while (@destroy) {
		132	my $coro = pop @destroy;
		133	$coro->{status} \|\|= [];
		134	$_->ready for @{delete $coro->{join} \|\| []};
		135	$coro->{_coro_state} = $manager->{_coro_state};
		136	}
114	&schedule;	137	&schedule;
115	}	138	}
116	};	139	};
117		140
118	# we really need priorities...
119	my @ready; # the ready queue. hehe, rather broken ;)
120
121	# static methods. not really.	141	# static methods. not really.
		142
		143	=back
122		144
123	=head2 STATIC METHODS	145	=head2 STATIC METHODS
124		146
125	Static methods are actually functions that operate on the current process only.	147	Static methods are actually functions that operate on the current process only.
126		148
…		…
134		156
135	# create a new coroutine that just prints its arguments	157	# create a new coroutine that just prints its arguments
136	async {	158	async {
137	print "@_\n";	159	print "@_\n";
138	} 1,2,3,4;	160	} 1,2,3,4;
139
140	The coderef you submit MUST NOT be a closure that refers to variables
141	in an outer scope. This does NOT work. Pass arguments into it instead.
142		161
143	=cut	162	=cut
144		163
145	sub async(&@) {	164	sub async(&@) {
146	my $pid = new Coro @_;	165	my $pid = new Coro @_;
…		…
155	into the ready queue, so calling this function usually means you will	174	into the ready queue, so calling this function usually means you will
156	never be called again.	175	never be called again.
157		176
158	=cut	177	=cut
159		178
160	my $prev;
161
162	sub schedule {
163	# should be done using priorities :(
164	($prev, $current) = ($current, shift @ready \|\| $idle);
165	Coro::State::transfer($prev, $current);
166	}
167
168	=item cede	179	=item cede
169		180
170	"Cede" to other processes. This function puts the current process into the	181	"Cede" to other processes. This function puts the current process into the
171	ready queue and calls C<schedule>, which has the effect of giving up the	182	ready queue and calls C<schedule>, which has the effect of giving up the
172	current "timeslice" to other coroutines of the same or higher priority.	183	current "timeslice" to other coroutines of the same or higher priority.
173		184
174	=cut	185	=cut
175		186
176	sub cede {	187	=item terminate [arg...]
		188
		189	Terminates the current process.
		190
		191	Future versions of this function will allow result arguments.
		192
		193	=cut
		194
		195	sub terminate {
		196	$current->{status} = [@_];
177	$current->ready;	197	$current->cancel;
178	&schedule;	198	&schedule;
179	}
180
181	=item terminate
182
183	Terminates the current process.
184
185	Future versions of this function will allow result arguments.
186
187	=cut
188
189	sub terminate {
190	push @destroy, $current;
191	$manager->ready;
192	&schedule;
193	# NORETURN	199	die; # NORETURN
194	}	200	}
195		201
196	=back	202	=back
197		203
198	# dynamic methods	204	# dynamic methods
…		…
204	=over 4	210	=over 4
205		211
206	=item new Coro \&sub [, @args...]	212	=item new Coro \&sub [, @args...]
207		213
208	Create a new process and return it. When the sub returns the process	214	Create a new process and return it. When the sub returns the process
209	automatically terminates. To start the process you must first put it into	215	automatically terminates as if C<terminate> with the returned values were
		216	called. To make the process run you must first put it into the ready queue
210	the ready queue by calling the ready method.	217	by calling the ready method.
211
212	The coderef you submit MUST NOT be a closure that refers to variables
213	in an outer scope. This does NOT work. Pass arguments into it instead.
214		218
215	=cut	219	=cut
216		220
217	sub _newcoro {	221	sub _newcoro {
218	terminate &{+shift};	222	terminate &{+shift};
…		…
225	}, $class;	229	}, $class;
226	}	230	}
227		231
228	=item $process->ready	232	=item $process->ready
229		233
230	Put the current process into the ready queue.	234	Put the given process into the ready queue.
231		235
232	=cut	236	=cut
233		237
234	sub ready {	238	=item $process->cancel
		239
		240	Like C<terminate>, but terminates the specified process instead.
		241
		242	=cut
		243
		244	sub cancel {
235	push @ready, $_[0];	245	push @destroy, $_[0];
		246	$manager->ready;
		247	&schedule if $current == $_[0];
		248	}
		249
		250	=item $process->join
		251
		252	Wait until the coroutine terminates and return any values given to the
		253	C<terminate> function. C<join> can be called multiple times from multiple
		254	processes.
		255
		256	=cut
		257
		258	sub join {
		259	my $self = shift;
		260	unless ($self->{status}) {
		261	push @{$self->{join}}, $current;
		262	&schedule;
		263	}
		264	wantarray ? @{$self->{status}} : $self->{status}[0];
		265	}
		266
		267	=item $oldprio = $process->prio($newprio)
		268
		269	Sets (or gets, if the argument is missing) the priority of the
		270	process. Higher priority processes get run before lower priority
		271	processes. Priorities are small signed integers (currently -4 .. +3),
		272	that you can refer to using PRIO_xxx constants (use the import tag :prio
		273	to get then):
		274
		275	PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
		276	3 > 1 > 0 > -1 > -3 > -4
		277
		278	# set priority to HIGH
		279	current->prio(PRIO_HIGH);
		280
		281	The idle coroutine ($Coro::idle) always has a lower priority than any
		282	existing coroutine.
		283
		284	Changing the priority of the current process will take effect immediately,
		285	but changing the priority of processes in the ready queue (but not
		286	running) will only take effect after the next schedule (of that
		287	process). This is a bug that will be fixed in some future version.
		288
		289	=cut
		290
		291	sub prio {
		292	my $old = $_[0]{prio};
		293	$_[0]{prio} = $_[1] if @_ > 1;
		294	$old;
		295	}
		296
		297	=item $newprio = $process->nice($change)
		298
		299	Similar to C<prio>, but subtract the given value from the priority (i.e.
		300	higher values mean lower priority, just as in unix).
		301
		302	=cut
		303
		304	sub nice {
		305	$_[0]{prio} -= $_[1];
		306	}
		307
		308	=item $olddesc = $process->desc($newdesc)
		309
		310	Sets (or gets in case the argument is missing) the description for this
		311	process. This is just a free-form string you can associate with a process.
		312
		313	=cut
		314
		315	sub desc {
		316	my $old = $_[0]{desc};
		317	$_[0]{desc} = $_[1] if @_ > 1;
		318	$old;
236	}	319	}
237		320
238	=back	321	=back
239		322
240	=cut	323	=cut
241		324
242	1;	325	1;
243		326
244	=head1 BUGS/LIMITATIONS	327	=head1 BUGS/LIMITATIONS
245		328
246	- could be faster, especially when the core would introduce special	329	- you must make very sure that no coro is still active on global
247	support for coroutines (like it does for threads).	330	destruction. very bad things might happen otherwise (usually segfaults).
248	- there is still a memleak on coroutine termination that I could not	331
249	identify. Could be as small as a single SV.
250	- this module is not well-tested.
251	- if variables or arguments "disappear" (become undef) or become
252	corrupted please contact the author so he cen iron out the
253	remaining bugs.
254	- this module is not thread-safe. You must only ever use this module from	332	- this module is not thread-safe. You should only ever use this module
255	the same thread (this requirement might be loosened in the future to	333	from the same thread (this requirement might be losened in the future
256	allow per-thread schedulers, but Coro::State does not yet allow this).	334	to allow per-thread schedulers, but Coro::State does not yet allow
		335	this).
257		336
258	=head1 SEE ALSO	337	=head1 SEE ALSO
259		338
260	L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,	339	L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
261	L<Coro::Signal>, L<Coro::State>, L<Coro::Event>.	340	L<Coro::Signal>, L<Coro::State>, L<Coro::Timer>, L<Coro::Event>,
		341	L<Coro::L<Coro::RWLock>, Handle>, L<Coro::Socket>.
262		342
263	=head1 AUTHOR	343	=head1 AUTHOR
264		344
265	Marc Lehmann <pcg@goof.com>	345	Marc Lehmann <pcg@goof.com>
266	http://www.goof.com/pcg/marc/	346	http://www.goof.com/pcg/marc/

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Comparing Coro/Coro.pm (file contents): Revision 1.24 by root, Wed Jul 25 04:14:37 2001 UTC vs. Revision 1.57 by pcg, Sun Nov 30 22:49:25 2003 UTC

Diff Legend

Comparing Coro/Coro.pm (file contents):
Revision 1.24 by root, Wed Jul 25 04:14:37 2001 UTC vs.
Revision 1.57 by pcg, Sun Nov 30 22:49:25 2003 UTC