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

Comparing Coro/Coro.pm (file contents):
Revision 1.12 by root, Sun Jul 15 15:58:16 2001 UTC vs.
Revision 1.83 by root, Fri Nov 24 15:34:33 2006 UTC

…		…
14		14
15	sub some_func : Coro {	15	sub some_func : Coro {
16	# some more async code	16	# some more async code
17	}	17	}
18		18
19	yield;	19	cede;
20		20
21	=head1 DESCRIPTION	21	=head1 DESCRIPTION
22		22
		23	This module collection manages coroutines. Coroutines are similar to
		24	threads but don't run in parallel.
		25
		26	In this module, coroutines are defined as "callchain + lexical variables
		27	+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
		28	callchain, it's own set of lexicals and it's own set of perl's most
		29	important global variables.
		30
23	=cut	31	=cut
24		32
25	package Coro;	33	package Coro;
26		34
		35	use strict;
		36	no warnings "uninitialized";
		37
27	use Coro::State;	38	use Coro::State;
28		39
29	use base Exporter;	40	use base qw(Coro::State Exporter);
30		41
		42	our $idle; # idle handler
		43	our $main; # main coroutine
		44	our $current; # current coroutine
		45
31	$VERSION = 0.05;	46	our $VERSION = '2.5';
32		47
33	@EXPORT = qw(async yield schedule);	48	our @EXPORT = qw(async cede schedule terminate current);
34	@EXPORT_OK = qw($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}};
35		53
36	{	54	{
37	use subs 'async';
38
39	my @async;	55	my @async;
		56	my $init;
40		57
41	# this way of handling attributes simply is NOT scalable ;()	58	# this way of handling attributes simply is NOT scalable ;()
42	sub import {	59	sub import {
		60	no strict 'refs';
		61
43	Coro->export_to_level(1, @_);	62	Coro->export_to_level(1, @_);
		63
44	my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};	64	my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
45	*{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub {	65	*{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub {
46	my ($package, $ref) = (shift, shift);	66	my ($package, $ref) = (shift, shift);
47	my @attrs;	67	my @attrs;
48	for (@_) {	68	for (@_) {
49	if ($_ eq "Coro") {	69	if ($_ eq "Coro") {
50	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	}
51	} else {	78	} else {
52	push @attrs, @_;	79	push @attrs, $_;
53	}	80	}
54	}	81	}
55	return $old ? $old->($package, $name, @attrs) : @attrs;	82	return $old ? $old->($package, $ref, @attrs) : @attrs;
56	};	83	};
57	}	84	}
58		85
59	sub INIT {
60	async pop @async while @async;
61	}
62	}	86	}
		87
		88	=over 4
63		89
64	=item $main	90	=item $main
65		91
66	This coroutine represents the main program.	92	This coroutine represents the main program.
67		93
68	=cut	94	=cut
69		95
70	our $main = new Coro;	96	$main = new Coro;
71		97
72	=item $current	98	=item $current (or as function: current)
73		99
74	The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).	100	The current coroutine (the last coroutine switched to). The initial value
		101	is C<$main> (of course).
		102
		103	This variable is B<strictly> I<read-only>. It is provided for performance
		104	reasons. If performance is not essentiel you are encouraged to use the
		105	C<Coro::current> function instead.
75		106
76	=cut	107	=cut
77		108
78	# maybe some other module used Coro::Specific before...	109	# maybe some other module used Coro::Specific before...
79	if ($current) {	110	if ($current) {
80	$main->{specific} = $current->{specific};	111	$main->{specific} = $current->{specific};
81	}	112	}
82		113
83	our $current = $main;	114	$current = $main;
		115
		116	sub current() { $current }
84		117
85	=item $idle	118	=item $idle
86		119
87	The coroutine to switch to when no other coroutine is running. The default	120	A callback that is called whenever the scheduler finds no ready coroutines
88	implementation prints "FATAL: deadlock detected" and exits.	121	to run. The default implementation prints "FATAL: deadlock detected" and
		122	exits.
89		123
90	=cut	124	This hook is overwritten by modules such as C<Coro::Timer> and
		125	C<Coro::Event> to wait on an external event that hopefully wakes up some
		126	coroutine.
91		127
92	# should be done using priorities :(	128	=cut
93	our $idle = new Coro sub {	129
		130	$idle = sub {
94	print STDERR "FATAL: deadlock detected\n";	131	print STDERR "FATAL: deadlock detected\n";
95	exit(51);	132	exit (51);
96	};	133	};
97		134
98	# we really need priorities...	135	# this coroutine is necessary because a coroutine
99	my @ready = (); # the ready queue. hehe, rather broken ;)	136	# cannot destroy itself.
		137	my @destroy;
		138	my $manager;
		139	$manager = new Coro sub {
		140	while () {
		141	# by overwriting the state object with the manager we destroy it
		142	# while still being able to schedule this coroutine (in case it has
		143	# been readied multiple times. this is harmless since the manager
		144	# can be called as many times as neccessary and will always
		145	# remove itself from the runqueue
		146	while (@destroy) {
		147	my $coro = pop @destroy;
		148	$coro->{status} \|\|= [];
		149	$_->ready for @{delete $coro->{join} \|\| []};
		150
		151	# the next line destroys the coro state, but keeps the
		152	# process itself intact (we basically make it a zombie
		153	# process that always runs the manager thread, so it's possible
		154	# to transfer() to this process).
		155	$coro->_clone_state_from ($manager);
		156	}
		157	&schedule;
		158	}
		159	};
100		160
101	# static methods. not really.	161	# static methods. not really.
102		162
		163	=back
		164
103	=head2 STATIC METHODS	165	=head2 STATIC METHODS
104		166
105	Static methods are actually functions that operate on the current process only.	167	Static methods are actually functions that operate on the current process only.
106		168
107	=over 4	169	=over 4
108		170
109	=item async { ... };	171	=item async { ... } [@args...]
110		172
111	Create a new asynchronous process and return it's process object	173	Create a new asynchronous process and return it's process object
112	(usually unused). When the sub returns the new process is automatically	174	(usually unused). When the sub returns the new process is automatically
113	terminated.	175	terminated.
114		176
115	=cut	177	When the coroutine dies, the program will exit, just as in the main
		178	program.
116		179
		180	# create a new coroutine that just prints its arguments
		181	async {
		182	print "@_\n";
		183	} 1,2,3,4;
		184
		185	=cut
		186
117	sub async(&) {	187	sub async(&@) {
118	my $pid = new Coro $_[0];	188	my $pid = new Coro @_;
		189	$manager->ready; # this ensures that the stack is cloned from the manager
119	$pid->ready;	190	$pid->ready;
120	$pid;	191	$pid;
121	}	192	}
122		193
123	=item schedule	194	=item schedule
…		…
126	into the ready queue, so calling this function usually means you will	197	into the ready queue, so calling this function usually means you will
127	never be called again.	198	never be called again.
128		199
129	=cut	200	=cut
130		201
131	my $prev;
132
133	sub schedule {
134	local @_;
135	# should be done using priorities :(
136	($prev, $current) = ($current, shift @ready \|\| $idle);
137	Coro::State::transfer($prev, $current);
138	}
139
140	=item yield	202	=item cede
141		203
142	Yield to other processes. This function puts the current process into the	204	"Cede" to other processes. This function puts the current process into the
143	ready queue and calls C<schedule>.	205	ready queue and calls C<schedule>, which has the effect of giving up the
		206	current "timeslice" to other coroutines of the same or higher priority.
144		207
145	=cut	208	=cut
146		209
147	sub yield {
148	$current->ready;
149	&schedule;
150	}
151
152	=item terminate	210	=item terminate [arg...]
153		211
154	Terminates the current process.	212	Terminates the current process with the given status values (see L<cancel>).
155		213
156	=cut	214	=cut
157		215
158	sub terminate {	216	sub terminate {
159	&schedule;	217	$current->cancel (@_);
160	}	218	}
161		219
162	=back	220	=back
163		221
164	# dynamic methods	222	# dynamic methods
…		…
167		225
168	These are the methods you can call on process objects.	226	These are the methods you can call on process objects.
169		227
170	=over 4	228	=over 4
171		229
172	=item new Coro \⊂	230	=item new Coro \&sub [, @args...]
173		231
174	Create a new process and return it. When the sub returns the process	232	Create a new process and return it. When the sub returns the process
175	automatically terminates. To start the process you must first put it into	233	automatically terminates as if C<terminate> with the returned values were
		234	called. To make the process run you must first put it into the ready queue
176	the ready queue by calling the ready method.	235	by calling the ready method.
177		236
178	=cut	237	=cut
		238
		239	sub _newcoro {
		240	terminate &{+shift};
		241	}
179		242
180	sub new {	243	sub new {
181	my $class = shift;	244	my $class = shift;
182	my $proc = $_[0];	245
183	bless {	246	$class->SUPER::new (\&_newcoro, @_)
184	_coro_state => new Coro::State ($proc ? sub { &$proc; &terminate } : $proc),
185	}, $class;
186	}	247	}
187		248
188	=item $process->ready	249	=item $process->ready
189		250
190	Put the current process into the ready queue.	251	Put the given process into the ready queue.
191		252
192	=cut	253	=cut
193		254
194	sub ready {	255	=item $process->cancel (arg...)
195	push @ready, $_[0];	256
		257	Terminates the given process and makes it return the given arguments as
		258	status (default: the empty list).
		259
		260	=cut
		261
		262	sub cancel {
		263	my $self = shift;
		264	$self->{status} = [@_];
		265	push @destroy, $self;
		266	$manager->ready;
		267	&schedule if $current == $self;
		268	}
		269
		270	=item $process->join
		271
		272	Wait until the coroutine terminates and return any values given to the
		273	C<terminate> or C<cancel> functions. C<join> can be called multiple times
		274	from multiple processes.
		275
		276	=cut
		277
		278	sub join {
		279	my $self = shift;
		280	unless ($self->{status}) {
		281	push @{$self->{join}}, $current;
		282	&schedule;
		283	}
		284	wantarray ? @{$self->{status}} : $self->{status}[0];
		285	}
		286
		287	=item $oldprio = $process->prio ($newprio)
		288
		289	Sets (or gets, if the argument is missing) the priority of the
		290	process. Higher priority processes get run before lower priority
		291	processes. Priorities are small signed integers (currently -4 .. +3),
		292	that you can refer to using PRIO_xxx constants (use the import tag :prio
		293	to get then):
		294
		295	PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
		296	3 > 1 > 0 > -1 > -3 > -4
		297
		298	# set priority to HIGH
		299	current->prio(PRIO_HIGH);
		300
		301	The idle coroutine ($Coro::idle) always has a lower priority than any
		302	existing coroutine.
		303
		304	Changing the priority of the current process will take effect immediately,
		305	but changing the priority of processes in the ready queue (but not
		306	running) will only take effect after the next schedule (of that
		307	process). This is a bug that will be fixed in some future version.
		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	=item $olddesc = $process->desc ($newdesc)
		315
		316	Sets (or gets in case the argument is missing) the description for this
		317	process. This is just a free-form string you can associate with a process.
		318
		319	=cut
		320
		321	sub desc {
		322	my $old = $_[0]{desc};
		323	$_[0]{desc} = $_[1] if @_ > 1;
		324	$old;
196	}	325	}
197		326
198	=back	327	=back
199		328
200	=cut	329	=cut
201		330
202	1;	331	1;
203		332
		333	=head1 BUGS/LIMITATIONS
		334
		335	- you must make very sure that no coro is still active on global
		336	destruction. very bad things might happen otherwise (usually segfaults).
		337
		338	- this module is not thread-safe. You should only ever use this module
		339	from the same thread (this requirement might be losened in the future
		340	to allow per-thread schedulers, but Coro::State does not yet allow
		341	this).
		342
204	=head1 SEE ALSO	343	=head1 SEE ALSO
205		344
206	L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,	345	Support/Utility: L<Coro::Cont>, L<Coro::Specific>, L<Coro::State>, L<Coro::Util>.
207	L<Coro::Signal>, L<Coro::State>, L<Coro::Event>.	346
		347	Locking/IPC: L<Coro::Signal>, L<Coro::Channel>, L<Coro::Semaphore>, L<Coro::SemaphoreSet>, L<Coro::RWLock>.
		348
		349	Event/IO: L<Coro::Timer>, L<Coro::Event>, L<Coro::Handle>, L<Coro::Socket>, L<Coro::Select>.
		350
		351	Embedding: L<Coro:MakeMaker>
208		352
209	=head1 AUTHOR	353	=head1 AUTHOR
210		354
211	Marc Lehmann <pcg@goof.com>	355	Marc Lehmann <schmorp@schmorp.de>
212	http://www.goof.com/pcg/marc/	356	http://home.schmorp.de/
213		357
214	=cut	358	=cut
215		359

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Comparing Coro/Coro.pm (file contents): Revision 1.12 by root, Sun Jul 15 15:58:16 2001 UTC vs. Revision 1.83 by root, Fri Nov 24 15:34:33 2006 UTC

Diff Legend

Comparing Coro/Coro.pm (file contents):
Revision 1.12 by root, Sun Jul 15 15:58:16 2001 UTC vs.
Revision 1.83 by root, Fri Nov 24 15:34:33 2006 UTC