[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 1.80 by root, Mon Nov 6 19:56:26 2006 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	use strict;
		36	no warnings "uninitialized";
		37
37	use Coro::State;	38	use Coro::State;
38		39
39	use base Exporter;	40	use base Exporter::;
40		41
41	$VERSION = 0.12;	42	our $idle; # idle coroutine
		43	our $main; # main coroutine
		44	our $current; # current coroutine
42		45
		46	our $VERSION = '2.5';
		47
43	@EXPORT = qw(async cede schedule terminate current);	48	our @EXPORT = qw(async cede schedule terminate current);
44	@EXPORT_OK = qw($current);	49	our %EXPORT_TAGS = (
		50	prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],
		51	);
		52	our @EXPORT_OK = @{$EXPORT_TAGS{prio}};
45		53
46	{	54	{
47	my @async;	55	my @async;
		56	my $init;
48		57
49	# this way of handling attributes simply is NOT scalable ;()	58	# this way of handling attributes simply is NOT scalable ;()
50	sub import {	59	sub import {
		60	no strict 'refs';
		61
51	Coro->export_to_level(1, @_);	62	Coro->export_to_level(1, @_);
		63
52	my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};	64	my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
53	*{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub {	65	*{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub {
54	my ($package, $ref) = (shift, shift);	66	my ($package, $ref) = (shift, shift);
55	my @attrs;	67	my @attrs;
56	for (@_) {	68	for (@_) {
57	if ($_ eq "Coro") {	69	if ($_ eq "Coro") {
58	push @async, $ref;	70	push @async, $ref;
		71	unless ($init++) {
		72	eval q{
		73	sub INIT {
		74	&async(pop @async) while @async;
		75	}
		76	};
		77	}
59	} else {	78	} else {
60	push @attrs, $_;	79	push @attrs, $_;
61	}	80	}
62	}	81	}
63	return $old ? $old->($package, $ref, @attrs) : @attrs;	82	return $old ? $old->($package, $ref, @attrs) : @attrs;
64	};	83	};
65	}	84	}
66		85
67	sub INIT {
68	&async(pop @async) while @async;
69	}
70	}	86	}
		87
		88	=over 4
71		89
72	=item $main	90	=item $main
73		91
74	This coroutine represents the main program.	92	This coroutine represents the main program.
75		93
76	=cut	94	=cut
77		95
78	our $main = new Coro;	96	$main = new Coro;
79		97
80	=item $current (or as function: current)	98	=item $current (or as function: current)
81		99
82	The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).	100	The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
83		101
…		…
86	# maybe some other module used Coro::Specific before...	104	# maybe some other module used Coro::Specific before...
87	if ($current) {	105	if ($current) {
88	$main->{specific} = $current->{specific};	106	$main->{specific} = $current->{specific};
89	}	107	}
90		108
91	our $current = $main;	109	$current = $main;
92		110
93	sub current() { $current }	111	sub current() { $current }
94		112
95	=item $idle	113	=item $idle
96		114
…		…
98	implementation prints "FATAL: deadlock detected" and exits.	116	implementation prints "FATAL: deadlock detected" and exits.
99		117
100	=cut	118	=cut
101		119
102	# should be done using priorities :(	120	# should be done using priorities :(
103	our $idle = new Coro sub {	121	$idle = new Coro sub {
104	print STDERR "FATAL: deadlock detected\n";	122	print STDERR "FATAL: deadlock detected\n";
105	exit(51);	123	exit(51);
106	};	124	};
107		125
108	# this coroutine is necessary because a coroutine	126	# this coroutine is necessary because a coroutine
109	# cannot destroy itself.	127	# cannot destroy itself.
110	my @destroy;	128	my @destroy;
		129	my $manager;
111	my $manager = new Coro sub {	130	$manager = new Coro sub {
112	while() {	131	while () {
113	delete ((pop @destroy)->{_coro_state}) while @destroy;	132	# by overwriting the state object with the manager we destroy it
		133	# while still being able to schedule this coroutine (in case it has
		134	# been readied multiple times. this is harmless since the manager
		135	# can be called as many times as neccessary and will always
		136	# remove itself from the runqueue
		137	while (@destroy) {
		138	my $coro = pop @destroy;
		139	$coro->{status} \|\|= [];
		140	$_->ready for @{delete $coro->{join} \|\| []};
		141
		142	# the next line destroys the _coro_state, but keeps the
		143	# process itself intact (we basically make it a zombie
		144	# process that always runs the manager thread, so it's possible
		145	# to transfer() to this process).
		146	$coro->{_coro_state} = $manager->{_coro_state};
		147	}
114	&schedule;	148	&schedule;
115	}	149	}
116	};	150	};
117		151
118	# we really need priorities...
119	my @ready; # the ready queue. hehe, rather broken ;)
120
121	# static methods. not really.	152	# static methods. not really.
		153
		154	=back
122		155
123	=head2 STATIC METHODS	156	=head2 STATIC METHODS
124		157
125	Static methods are actually functions that operate on the current process only.	158	Static methods are actually functions that operate on the current process only.
126		159
…		…
129	=item async { ... } [@args...]	162	=item async { ... } [@args...]
130		163
131	Create a new asynchronous process and return it's process object	164	Create a new asynchronous process and return it's process object
132	(usually unused). When the sub returns the new process is automatically	165	(usually unused). When the sub returns the new process is automatically
133	terminated.	166	terminated.
		167
		168	When the coroutine dies, the program will exit, just as in the main
		169	program.
134		170
135	# create a new coroutine that just prints its arguments	171	# create a new coroutine that just prints its arguments
136	async {	172	async {
137	print "@_\n";	173	print "@_\n";
138	} 1,2,3,4;	174	} 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		175
143	=cut	176	=cut
144		177
145	sub async(&@) {	178	sub async(&@) {
146	my $pid = new Coro @_;	179	my $pid = new Coro @_;
…		…
155	into the ready queue, so calling this function usually means you will	188	into the ready queue, so calling this function usually means you will
156	never be called again.	189	never be called again.
157		190
158	=cut	191	=cut
159		192
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	193	=item cede
169		194
170	"Cede" to other processes. This function puts the current process into the	195	"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	196	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.	197	current "timeslice" to other coroutines of the same or higher priority.
173		198
174	=cut	199	=cut
175		200
176	sub cede {
177	$current->ready;
178	&schedule;
179	}
180
181	=item terminate	201	=item terminate [arg...]
182		202
183	Terminates the current process.	203	Terminates the current process with the given status values (see L<cancel>).
184
185	Future versions of this function will allow result arguments.
186		204
187	=cut	205	=cut
188		206
189	sub terminate {	207	sub terminate {
190	push @destroy, $current;	208	$current->cancel (@_);
191	$manager->ready;
192	&schedule;
193	# NORETURN
194	}	209	}
195		210
196	=back	211	=back
197		212
198	# dynamic methods	213	# dynamic methods
…		…
204	=over 4	219	=over 4
205		220
206	=item new Coro \&sub [, @args...]	221	=item new Coro \&sub [, @args...]
207		222
208	Create a new process and return it. When the sub returns the process	223	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	224	automatically terminates as if C<terminate> with the returned values were
		225	called. To make the process run you must first put it into the ready queue
210	the ready queue by calling the ready method.	226	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		227
215	=cut	228	=cut
216		229
217	sub _newcoro {	230	sub _newcoro {
218	terminate &{+shift};	231	terminate &{+shift};
…		…
225	}, $class;	238	}, $class;
226	}	239	}
227		240
228	=item $process->ready	241	=item $process->ready
229		242
230	Put the current process into the ready queue.	243	Put the given process into the ready queue.
231		244
232	=cut	245	=cut
233		246
234	sub ready {	247	=item $process->cancel (arg...)
235	push @ready, $_[0];	248
		249	Terminates the given process and makes it return the given arguments as
		250	status (default: the empty list).
		251
		252	=cut
		253
		254	sub cancel {
		255	my $self = shift;
		256	$self->{status} = [@_];
		257	push @destroy, $self;
		258	$manager->ready;
		259	&schedule if $current == $self;
		260	}
		261
		262	=item $process->join
		263
		264	Wait until the coroutine terminates and return any values given to the
		265	C<terminate> or C<cancel> functions. C<join> can be called multiple times
		266	from multiple processes.
		267
		268	=cut
		269
		270	sub join {
		271	my $self = shift;
		272	unless ($self->{status}) {
		273	push @{$self->{join}}, $current;
		274	&schedule;
		275	}
		276	wantarray ? @{$self->{status}} : $self->{status}[0];
		277	}
		278
		279	=item $oldprio = $process->prio($newprio)
		280
		281	Sets (or gets, if the argument is missing) the priority of the
		282	process. Higher priority processes get run before lower priority
		283	processes. Priorities are small signed integers (currently -4 .. +3),
		284	that you can refer to using PRIO_xxx constants (use the import tag :prio
		285	to get then):
		286
		287	PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
		288	3 > 1 > 0 > -1 > -3 > -4
		289
		290	# set priority to HIGH
		291	current->prio(PRIO_HIGH);
		292
		293	The idle coroutine ($Coro::idle) always has a lower priority than any
		294	existing coroutine.
		295
		296	Changing the priority of the current process will take effect immediately,
		297	but changing the priority of processes in the ready queue (but not
		298	running) will only take effect after the next schedule (of that
		299	process). This is a bug that will be fixed in some future version.
		300
		301	=cut
		302
		303	sub prio {
		304	my $old = $_[0]{prio};
		305	$_[0]{prio} = $_[1] if @_ > 1;
		306	$old;
		307	}
		308
		309	=item $newprio = $process->nice($change)
		310
		311	Similar to C<prio>, but subtract the given value from the priority (i.e.
		312	higher values mean lower priority, just as in unix).
		313
		314	=cut
		315
		316	sub nice {
		317	$_[0]{prio} -= $_[1];
		318	}
		319
		320	=item $olddesc = $process->desc($newdesc)
		321
		322	Sets (or gets in case the argument is missing) the description for this
		323	process. This is just a free-form string you can associate with a process.
		324
		325	=cut
		326
		327	sub desc {
		328	my $old = $_[0]{desc};
		329	$_[0]{desc} = $_[1] if @_ > 1;
		330	$old;
236	}	331	}
237		332
238	=back	333	=back
239		334
240	=cut	335	=cut
241		336
242	1;	337	1;
243		338
244	=head1 BUGS/LIMITATIONS	339	=head1 BUGS/LIMITATIONS
245		340
246	- could be faster, especially when the core would introduce special	341	- you must make very sure that no coro is still active on global
247	support for coroutines (like it does for threads).	342	destruction. very bad things might happen otherwise (usually segfaults).
248	- there is still a memleak on coroutine termination that I could not	343
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	344	- 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	345	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).	346	to allow per-thread schedulers, but Coro::State does not yet allow
		347	this).
257		348
258	=head1 SEE ALSO	349	=head1 SEE ALSO
259		350
260	L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,	351	Support/Utility: L<Coro::Cont>, L<Coro::Specific>, L<Coro::State>, L<Coro::Util>.
261	L<Coro::Signal>, L<Coro::State>, L<Coro::Event>.	352
		353	Locking/IPC: L<Coro::Signal>, L<Coro::Channel>, L<Coro::Semaphore>, L<Coro::SemaphoreSet>, L<Coro::RWLock>.
		354
		355	Event/IO: L<Coro::Timer>, L<Coro::Event>, L<Coro::Handle>, L<Coro::Socket>, L<Coro::Select>.
		356
		357	Embedding: L<Coro:MakeMaker>
262		358
263	=head1 AUTHOR	359	=head1 AUTHOR
264		360
265	Marc Lehmann <pcg@goof.com>	361	Marc Lehmann <schmorp@schmorp.de>
266	http://www.goof.com/pcg/marc/	362	http://home.schmorp.de/
267		363
268	=cut	364	=cut
269		365

Diff Legend

-–
+Removed lines
-+
+Added lines
-<
+Changed lines
->
+Changed lines

Comparing Coro/Coro.pm (file contents): Revision 1.24 by root, Wed Jul 25 04:14:37 2001 UTC vs. Revision 1.80 by root, Mon Nov 6 19:56:26 2006 UTC

Diff Legend

Comparing Coro/Coro.pm (file contents):
Revision 1.24 by root, Wed Jul 25 04:14:37 2001 UTC vs.
Revision 1.80 by root, Mon Nov 6 19:56:26 2006 UTC