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

Comparing Coro/Coro.pm (file contents):
Revision 1.23 by root, Mon Jul 23 04:23:32 2001 UTC vs.
Revision 1.55 by pcg, Wed Nov 5 20:02:44 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 = 0.10;	43	$VERSION = 0.8;
42		44
43	@EXPORT = qw(async cede schedule terminate current);	45	@EXPORT = qw(async cede schedule terminate current);
44	@EXPORT_OK = qw($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	# we really need priorities...	120	# this coroutine is necessary because a coroutine
109	my @ready; # the ready queue. hehe, rather broken ;)	121	# cannot destroy itself.
		122	my @destroy;
		123	my $manager;
		124	$manager = new Coro sub {
		125	while() {
		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	}
		137	&schedule;
		138	}
		139	};
110		140
111	# static methods. not really.	141	# static methods. not really.
		142
		143	=back
112		144
113	=head2 STATIC METHODS	145	=head2 STATIC METHODS
114		146
115	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.
116		148
…		…
132		164
133	=cut	165	=cut
134		166
135	sub async(&@) {	167	sub async(&@) {
136	my $pid = new Coro @_;	168	my $pid = new Coro @_;
		169	$manager->ready; # this ensures that the stack is cloned from the manager
137	$pid->ready;	170	$pid->ready;
138	$pid;	171	$pid;
139	}	172	}
140		173
141	=item schedule	174	=item schedule
…		…
144	into the ready queue, so calling this function usually means you will	177	into the ready queue, so calling this function usually means you will
145	never be called again.	178	never be called again.
146		179
147	=cut	180	=cut
148		181
149	my $prev;
150
151	sub schedule {
152	# should be done using priorities :(
153	($prev, $current) = ($current, shift @ready \|\| $idle);
154	Coro::State::transfer($prev, $current);
155	}
156
157	=item cede	182	=item cede
158		183
159	"Cede" to other processes. This function puts the current process into the	184	"Cede" to other processes. This function puts the current process into the
160	ready queue and calls C<schedule>, which has the effect of giving up the	185	ready queue and calls C<schedule>, which has the effect of giving up the
161	current "timeslice" to other coroutines of the same or higher priority.	186	current "timeslice" to other coroutines of the same or higher priority.
162		187
163	=cut	188	=cut
164		189
165	sub cede {	190	=item terminate [arg...]
		191
		192	Terminates the current process.
		193
		194	Future versions of this function will allow result arguments.
		195
		196	=cut
		197
		198	sub terminate {
		199	$current->{status} = [@_];
166	$current->ready;	200	$current->cancel;
167	&schedule;	201	&schedule;
168	}
169
170	=item terminate
171
172	Terminates the current process.
173
174	Future versions of this function will allow result arguments.
175
176	=cut
177
178	# this coroutine is necessary because a coroutine
179	# cannot destroy itself.
180	my @destroy;
181	my $terminate = new Coro sub {
182	while() {
183	delete ((pop @destroy)->{_coro_state}) while @destroy;
184	&schedule;
185	}
186	};
187
188	sub terminate {
189	push @destroy, $current;
190	$terminate->ready;
191	&schedule;
192	# NORETURN	202	die; # NORETURN
193	}	203	}
194		204
195	=back	205	=back
196		206
197	# dynamic methods	207	# dynamic methods
…		…
203	=over 4	213	=over 4
204		214
205	=item new Coro \&sub [, @args...]	215	=item new Coro \&sub [, @args...]
206		216
207	Create a new process and return it. When the sub returns the process	217	Create a new process and return it. When the sub returns the process
208	automatically terminates. To start the process you must first put it into	218	automatically terminates as if C<terminate> with the returned values were
		219	called. To make the process run you must first put it into the ready queue
209	the ready queue by calling the ready method.	220	by calling the ready method.
210
211	The coderef you submit MUST NOT be a closure that refers to variables
212	in an outer scope. This does NOT work. Pass arguments into it instead.
213		221
214	=cut	222	=cut
215		223
216	sub _newcoro {	224	sub _newcoro {
217	terminate &{+shift};	225	terminate &{+shift};
…		…
224	}, $class;	232	}, $class;
225	}	233	}
226		234
227	=item $process->ready	235	=item $process->ready
228		236
229	Put the current process into the ready queue.	237	Put the given process into the ready queue.
230		238
231	=cut	239	=cut
232		240
233	sub ready {	241	=item $process->cancel
		242
		243	Like C<terminate>, but terminates the specified process instead.
		244
		245	=cut
		246
		247	sub cancel {
234	push @ready, $_[0];	248	push @destroy, $_[0];
		249	$manager->ready;
		250	&schedule if $current == $_[0];
		251	}
		252
		253	=item $process->join
		254
		255	Wait until the coroutine terminates and return any values given to the
		256	C<terminate> function. C<join> can be called multiple times from multiple
		257	processes.
		258
		259	=cut
		260
		261	sub join {
		262	my $self = shift;
		263	unless ($self->{status}) {
		264	push @{$self->{join}}, $current;
		265	&schedule;
		266	}
		267	wantarray ? @{$self->{status}} : $self->{status}[0];
		268	}
		269
		270	=item $oldprio = $process->prio($newprio)
		271
		272	Sets (or gets, if the argument is missing) the priority of the
		273	process. Higher priority processes get run before lower priority
		274	processes. Priorities are small signed integers (currently -4 .. +3),
		275	that you can refer to using PRIO_xxx constants (use the import tag :prio
		276	to get then):
		277
		278	PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
		279	3 > 1 > 0 > -1 > -3 > -4
		280
		281	# set priority to HIGH
		282	current->prio(PRIO_HIGH);
		283
		284	The idle coroutine ($Coro::idle) always has a lower priority than any
		285	existing coroutine.
		286
		287	Changing the priority of the current process will take effect immediately,
		288	but changing the priority of processes in the ready queue (but not
		289	running) will only take effect after the next schedule (of that
		290	process). This is a bug that will be fixed in some future version.
		291
		292	=cut
		293
		294	sub prio {
		295	my $old = $_[0]{prio};
		296	$_[0]{prio} = $_[1] if @_ > 1;
		297	$old;
		298	}
		299
		300	=item $newprio = $process->nice($change)
		301
		302	Similar to C<prio>, but subtract the given value from the priority (i.e.
		303	higher values mean lower priority, just as in unix).
		304
		305	=cut
		306
		307	sub nice {
		308	$_[0]{prio} -= $_[1];
		309	}
		310
		311	=item $olddesc = $process->desc($newdesc)
		312
		313	Sets (or gets in case the argument is missing) the description for this
		314	process. This is just a free-form string you can associate with a process.
		315
		316	=cut
		317
		318	sub desc {
		319	my $old = $_[0]{desc};
		320	$_[0]{desc} = $_[1] if @_ > 1;
		321	$old;
235	}	322	}
236		323
237	=back	324	=back
238		325
239	=cut	326	=cut
240		327
241	1;	328	1;
242		329
243	=head1 BUGS/LIMITATIONS	330	=head1 BUGS/LIMITATIONS
244		331
245	- could be faster, especially when the core would introduce special	332	- you must make very sure that no coro is still active on global
246	support for coroutines (like it does for threads).	333	destruction. very bad things might happen otherwise (usually segfaults).
247	- there is still a memleak on coroutine termination that I could not	334
248	identify. Could be as small as a single SV.
249	- this module is not well-tested.
250	- if variables or arguments "disappear" (become undef) or become
251	corrupted please contact the author so he cen iron out the
252	remaining bugs.
253	- this module is not thread-safe. You must only ever use this module from	335	- this module is not thread-safe. You should only ever use this module
254	the same thread (this requirement might be loosened in the future to	336	from the same thread (this requirement might be losened in the future
255	allow per-thread schedulers, but Coro::State does not yet allow this).	337	to allow per-thread schedulers, but Coro::State does not yet allow
		338	this).
256		339
257	=head1 SEE ALSO	340	=head1 SEE ALSO
258		341
259	L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,	342	L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
260	L<Coro::Signal>, L<Coro::State>, L<Coro::Event>.	343	L<Coro::Signal>, L<Coro::State>, L<Coro::Timer>, L<Coro::Event>,
		344	L<Coro::L<Coro::RWLock>, Handle>, L<Coro::Socket>.
261		345
262	=head1 AUTHOR	346	=head1 AUTHOR
263		347
264	Marc Lehmann <pcg@goof.com>	348	Marc Lehmann <pcg@goof.com>
265	http://www.goof.com/pcg/marc/	349	http://www.goof.com/pcg/marc/

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Comparing Coro/Coro.pm (file contents): Revision 1.23 by root, Mon Jul 23 04:23:32 2001 UTC vs. Revision 1.55 by pcg, Wed Nov 5 20:02:44 2003 UTC

Diff Legend

Comparing Coro/Coro.pm (file contents):
Revision 1.23 by root, Mon Jul 23 04:23:32 2001 UTC vs.
Revision 1.55 by pcg, Wed Nov 5 20:02:44 2003 UTC