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

Comparing Coro/Coro.pm (file contents):
Revision 1.10 by root, Sun Jul 15 02:36:54 2001 UTC vs.
Revision 1.88 by root, Sun Nov 26 02:54:55 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 = 0.04;	46	our $VERSION = '3.0';
32		47
33	@EXPORT = qw(async yield schedule);	48	our @EXPORT = qw(async cede schedule terminate current);
34	@EXPORT_OK = qw($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; $manager = new Coro sub {
		139	while () {
		140	# by overwriting the state object with the manager we destroy it
		141	# while still being able to schedule this coroutine (in case it has
		142	# been readied multiple times. this is harmless since the manager
		143	# can be called as many times as neccessary and will always
		144	# remove itself from the runqueue
		145	while (@destroy) {
		146	my $coro = pop @destroy;
		147	$coro->{status} \|\|= [];
		148	$_->ready for @{delete $coro->{join} \|\| []};
		149
		150	# the next line destroys the coro state, but keeps the
		151	# process itself intact (we basically make it a zombie
		152	# process that always runs the manager thread, so it's possible
		153	# to transfer() to this process).
		154	$coro->_clone_state_from ($manager);
		155	}
		156	&schedule;
		157	}
		158	};
100		159
101	# static methods. not really.	160	# static methods. not really.
102		161
		162	=back
		163
103	=head2 STATIC METHODS	164	=head2 STATIC METHODS
104		165
105	Static methods are actually functions that operate on the current process only.	166	Static methods are actually functions that operate on the current process only.
106		167
107	=over 4	168	=over 4
108		169
109	=item async { ... };	170	=item async { ... } [@args...]
110		171
111	Create a new asynchronous process and return it's process object	172	Create a new asynchronous process and return it's process object
112	(usually unused). When the sub returns the new process is automatically	173	(usually unused). When the sub returns the new process is automatically
113	terminated.	174	terminated.
114		175
115	=cut	176	When the coroutine dies, the program will exit, just as in the main
		177	program.
116		178
		179	# create a new coroutine that just prints its arguments
		180	async {
		181	print "@_\n";
		182	} 1,2,3,4;
		183
		184	=cut
		185
117	sub async(&) {	186	sub async(&@) {
118	(new Coro $_[0])->ready;	187	my $pid = new Coro @_;
		188	$pid->ready;
		189	$pid
119	}	190	}
120		191
121	=item schedule	192	=item schedule
122		193
123	Calls the scheduler. Please note that the current process will not be put	194	Calls the scheduler. Please note that the current process will not be put
124	into the ready queue, so calling this function usually means you will	195	into the ready queue, so calling this function usually means you will
125	never be called again.	196	never be called again.
126		197
127	=cut	198	=cut
128		199
129	my $prev;
130
131	sub schedule {
132	# should be done using priorities :(
133	($prev, $current) = ($current, shift @ready \|\| $idle);
134	Coro::State::transfer($prev, $current);
135	}
136
137	=item yield	200	=item cede
138		201
139	Yield to other processes. This function puts the current process into the	202	"Cede" to other processes. This function puts the current process into the
140	ready queue and calls C<schedule>.	203	ready queue and calls C<schedule>, which has the effect of giving up the
		204	current "timeslice" to other coroutines of the same or higher priority.
141		205
142	=cut	206	=cut
143		207
144	sub yield {
145	$current->ready;
146	&schedule;
147	}
148
149	=item terminate	208	=item terminate [arg...]
150		209
151	Terminates the current process.	210	Terminates the current process with the given status values (see L<cancel>).
152		211
153	=cut	212	=cut
154		213
155	sub terminate {	214	sub terminate {
156	&schedule;	215	$current->cancel (@_);
157	}	216	}
158		217
159	=back	218	=back
160		219
161	# dynamic methods	220	# dynamic methods
…		…
164		223
165	These are the methods you can call on process objects.	224	These are the methods you can call on process objects.
166		225
167	=over 4	226	=over 4
168		227
169	=item new Coro \⊂	228	=item new Coro \&sub [, @args...]
170		229
171	Create a new process and return it. When the sub returns the process	230	Create a new process and return it. When the sub returns the process
172	automatically terminates. To start the process you must first put it into	231	automatically terminates as if C<terminate> with the returned values were
		232	called. To make the process run you must first put it into the ready queue
173	the ready queue by calling the ready method.	233	by calling the ready method.
174		234
175	=cut	235	=cut
		236
		237	sub _new_coro {
		238	terminate &{+shift};
		239	}
176		240
177	sub new {	241	sub new {
178	my $class = shift;	242	my $class = shift;
179	my $proc = $_[0];	243
180	bless {	244	$class->SUPER::new (\&_new_coro, @_)
181	_coro_state => new Coro::State ($proc ? sub { &$proc; &terminate } : $proc),
182	}, $class;
183	}	245	}
184		246
185	=item $process->ready	247	=item $process->ready
186		248
187	Put the current process into the ready queue.	249	Put the given process into the ready queue.
188		250
189	=cut	251	=cut
190		252
191	sub ready {	253	=item $process->cancel (arg...)
192	push @ready, $_[0];	254
		255	Terminates the given process and makes it return the given arguments as
		256	status (default: the empty list).
		257
		258	=cut
		259
		260	sub cancel {
		261	my $self = shift;
		262	$self->{status} = [@_];
		263	push @destroy, $self;
		264	$manager->ready;
		265	&schedule if $current == $self;
		266	}
		267
		268	=item $process->join
		269
		270	Wait until the coroutine terminates and return any values given to the
		271	C<terminate> or C<cancel> functions. C<join> can be called multiple times
		272	from multiple processes.
		273
		274	=cut
		275
		276	sub join {
		277	my $self = shift;
		278	unless ($self->{status}) {
		279	push @{$self->{join}}, $current;
		280	&schedule;
		281	}
		282	wantarray ? @{$self->{status}} : $self->{status}[0];
		283	}
		284
		285	=item $oldprio = $process->prio ($newprio)
		286
		287	Sets (or gets, if the argument is missing) the priority of the
		288	process. Higher priority processes get run before lower priority
		289	processes. Priorities are small signed integers (currently -4 .. +3),
		290	that you can refer to using PRIO_xxx constants (use the import tag :prio
		291	to get then):
		292
		293	PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
		294	3 > 1 > 0 > -1 > -3 > -4
		295
		296	# set priority to HIGH
		297	current->prio(PRIO_HIGH);
		298
		299	The idle coroutine ($Coro::idle) always has a lower priority than any
		300	existing coroutine.
		301
		302	Changing the priority of the current process will take effect immediately,
		303	but changing the priority of processes in the ready queue (but not
		304	running) will only take effect after the next schedule (of that
		305	process). This is a bug that will be fixed in some future version.
		306
		307	=item $newprio = $process->nice ($change)
		308
		309	Similar to C<prio>, but subtract the given value from the priority (i.e.
		310	higher values mean lower priority, just as in unix).
		311
		312	=item $olddesc = $process->desc ($newdesc)
		313
		314	Sets (or gets in case the argument is missing) the description for this
		315	process. This is just a free-form string you can associate with a process.
		316
		317	=cut
		318
		319	sub desc {
		320	my $old = $_[0]{desc};
		321	$_[0]{desc} = $_[1] if @_ > 1;
		322	$old;
193	}	323	}
194		324
195	=back	325	=back
196		326
197	=cut	327	=cut
198		328
199	1;	329	1;
200		330
		331	=head1 BUGS/LIMITATIONS
		332
		333	- you must make very sure that no coro is still active on global
		334	destruction. very bad things might happen otherwise (usually segfaults).
		335
		336	- this module is not thread-safe. You should only ever use this module
		337	from the same thread (this requirement might be losened in the future
		338	to allow per-thread schedulers, but Coro::State does not yet allow
		339	this).
		340
201	=head1 SEE ALSO	341	=head1 SEE ALSO
202		342
203	L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,	343	Support/Utility: L<Coro::Cont>, L<Coro::Specific>, L<Coro::State>, L<Coro::Util>.
204	L<Coro::Signal>, L<Coro::State>, L<Coro::Event>.	344
		345	Locking/IPC: L<Coro::Signal>, L<Coro::Channel>, L<Coro::Semaphore>, L<Coro::SemaphoreSet>, L<Coro::RWLock>.
		346
		347	Event/IO: L<Coro::Timer>, L<Coro::Event>, L<Coro::Handle>, L<Coro::Socket>, L<Coro::Select>.
		348
		349	Embedding: L<Coro:MakeMaker>
205		350
206	=head1 AUTHOR	351	=head1 AUTHOR
207		352
208	Marc Lehmann <pcg@goof.com>	353	Marc Lehmann <schmorp@schmorp.de>
209	http://www.goof.com/pcg/marc/	354	http://home.schmorp.de/
210		355
211	=cut	356	=cut
212		357

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Comparing Coro/Coro.pm (file contents): Revision 1.10 by root, Sun Jul 15 02:36:54 2001 UTC vs. Revision 1.88 by root, Sun Nov 26 02:54:55 2006 UTC

Diff Legend

Comparing Coro/Coro.pm (file contents):
Revision 1.10 by root, Sun Jul 15 02:36:54 2001 UTC vs.
Revision 1.88 by root, Sun Nov 26 02:54:55 2006 UTC