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

Comparing Coro/Coro.pm (file contents):
Revision 1.8 by root, Sat Jul 14 22:14:21 2001 UTC vs.
Revision 1.85 by root, Sat Nov 25 00:56:35 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
31	$VERSION = 0.03;	42	our $idle; # idle handler
		43	our $main; # main coroutine
		44	our $current; # current coroutine
32		45
33	@EXPORT = qw(async yield schedule);	46	our $VERSION = '2.5';
34	@EXPORT_OK = qw($current);	47
		48	our @EXPORT = qw(async cede schedule terminate 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	}
63		87
64	my $idle = new Coro sub {	88	=over 4
65	&yield while 1;
66	};
67		89
68	=item $main	90	=item $main
69		91
70	This coroutine represents the main program.	92	This coroutine represents the main program.
71		93
72	=cut	94	=cut
73		95
74	$main = new Coro;	96	$main = new Coro;
75		97
76	=item $current	98	=item $current (or as function: current)
77		99
78	The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).	100	The current coroutine (the last coroutine switched to). The initial value
		101	is C<$main> (of course).
		102
		103	This variable is B<strictly> I<read-only>. It is provided for performance
		104	reasons. If performance is not essentiel you are encouraged to use the
		105	C<Coro::current> function instead.
79		106
80	=cut	107	=cut
81		108
82	# maybe some other module used Coro::Specific before...	109	# maybe some other module used Coro::Specific before...
83	if ($current) {	110	if ($current) {
84	$main->{specific} = $current->{specific};	111	$main->{specific} = $current->{specific};
85	}	112	}
86		113
87	$current = $main;	114	$current = $main;
88		115
89	# we really need priorities...	116	sub current() { $current }
90	my @ready = (); # the ready queue. hehe, rather broken ;)	117
		118	=item $idle
		119
		120	A callback that is called whenever the scheduler finds no ready coroutines
		121	to run. The default implementation prints "FATAL: deadlock detected" and
		122	exits.
		123
		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.
		127
		128	=cut
		129
		130	$idle = sub {
		131	print STDERR "FATAL: deadlock detected\n";
		132	exit (51);
		133	};
		134
		135	# this coroutine is necessary because a coroutine
		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	};
91		160
92	# static methods. not really.	161	# static methods. not really.
93		162
		163	=back
		164
94	=head2 STATIC METHODS	165	=head2 STATIC METHODS
95		166
96	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.
97		168
98	=over 4	169	=over 4
99		170
100	=item async { ... };	171	=item async { ... } [@args...]
101		172
102	Create a new asynchronous process and return it's process object	173	Create a new asynchronous process and return it's process object
103	(usually unused). When the sub returns the new process is automatically	174	(usually unused). When the sub returns the new process is automatically
104	terminated.	175	terminated.
105		176
106	=cut	177	When the coroutine dies, the program will exit, just as in the main
		178	program.
107		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
108	sub async(&) {	187	sub async(&@) {
109	(new Coro $_[0])->ready;	188	my $pid = new Coro @_;
		189	$pid->ready;
		190	$pid
110	}	191	}
111		192
112	=item schedule	193	=item schedule
113		194
114	Calls the scheduler. Please note that the current process will not be put	195	Calls the scheduler. Please note that the current process will not be put
115	into the ready queue, so calling this function usually means you will	196	into the ready queue, so calling this function usually means you will
116	never be called again.	197	never be called again.
117		198
118	=cut	199	=cut
119		200
120	my $prev;
121
122	sub schedule {
123	($prev, $current) = ($current, shift @ready);
124	Coro::State::transfer($prev, $current);
125	}
126
127	=item yield	201	=item cede
128		202
129	Yield to other processes. This function puts the current process into the	203	"Cede" to other processes. This function puts the current process into the
130	ready queue and calls C<schedule>.	204	ready queue and calls C<schedule>, which has the effect of giving up the
		205	current "timeslice" to other coroutines of the same or higher priority.
131		206
132	=cut	207	=cut
133		208
134	sub yield {
135	$current->ready;
136	&schedule;
137	}
138
139	=item terminate	209	=item terminate [arg...]
140		210
141	Terminates the current process.	211	Terminates the current process with the given status values (see L<cancel>).
142		212
143	=cut	213	=cut
144		214
145	sub terminate {	215	sub terminate {
146	&schedule;	216	$current->cancel (@_);
147	}	217	}
148		218
149	=back	219	=back
150		220
151	# dynamic methods	221	# dynamic methods
…		…
154		224
155	These are the methods you can call on process objects.	225	These are the methods you can call on process objects.
156		226
157	=over 4	227	=over 4
158		228
159	=item new Coro \⊂	229	=item new Coro \&sub [, @args...]
160		230
161	Create a new process and return it. When the sub returns the process	231	Create a new process and return it. When the sub returns the process
162	automatically terminates. To start the process you must first put it into	232	automatically terminates as if C<terminate> with the returned values were
		233	called. To make the process run you must first put it into the ready queue
163	the ready queue by calling the ready method.	234	by calling the ready method.
164		235
165	=cut	236	=cut
		237
		238	sub _new_coro {
		239	$current->_clear_idle_sp; # set the idle sp on the following cede
		240	_set_cede_self; # ensures that cede cede's us first
		241	cede;
		242	terminate &{+shift};
		243	}
166		244
167	sub new {	245	sub new {
168	my $class = shift;	246	my $class = shift;
169	my $proc = $_[0];	247
170	bless {	248	$class->SUPER::new (\&_new_coro, @_)
171	_coro_state => new Coro::State ($proc ? sub { &$proc; &terminate } : $proc),
172	}, $class;
173	}	249	}
174		250
175	=item $process->ready	251	=item $process->ready
176		252
177	Put the current process into the ready queue.	253	Put the given process into the ready queue.
178		254
179	=cut	255	=cut
180		256
181	sub ready {	257	=item $process->cancel (arg...)
182	push @ready, $_[0];	258
		259	Terminates the given process and makes it return the given arguments as
		260	status (default: the empty list).
		261
		262	=cut
		263
		264	sub cancel {
		265	my $self = shift;
		266	$self->{status} = [@_];
		267	push @destroy, $self;
		268	$manager->ready;
		269	&schedule if $current == $self;
		270	}
		271
		272	=item $process->join
		273
		274	Wait until the coroutine terminates and return any values given to the
		275	C<terminate> or C<cancel> functions. C<join> can be called multiple times
		276	from multiple processes.
		277
		278	=cut
		279
		280	sub join {
		281	my $self = shift;
		282	unless ($self->{status}) {
		283	push @{$self->{join}}, $current;
		284	&schedule;
		285	}
		286	wantarray ? @{$self->{status}} : $self->{status}[0];
		287	}
		288
		289	=item $oldprio = $process->prio ($newprio)
		290
		291	Sets (or gets, if the argument is missing) the priority of the
		292	process. Higher priority processes get run before lower priority
		293	processes. Priorities are small signed integers (currently -4 .. +3),
		294	that you can refer to using PRIO_xxx constants (use the import tag :prio
		295	to get then):
		296
		297	PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
		298	3 > 1 > 0 > -1 > -3 > -4
		299
		300	# set priority to HIGH
		301	current->prio(PRIO_HIGH);
		302
		303	The idle coroutine ($Coro::idle) always has a lower priority than any
		304	existing coroutine.
		305
		306	Changing the priority of the current process will take effect immediately,
		307	but changing the priority of processes in the ready queue (but not
		308	running) will only take effect after the next schedule (of that
		309	process). This is a bug that will be fixed in some future version.
		310
		311	=item $newprio = $process->nice ($change)
		312
		313	Similar to C<prio>, but subtract the given value from the priority (i.e.
		314	higher values mean lower priority, just as in unix).
		315
		316	=item $olddesc = $process->desc ($newdesc)
		317
		318	Sets (or gets in case the argument is missing) the description for this
		319	process. This is just a free-form string you can associate with a process.
		320
		321	=cut
		322
		323	sub desc {
		324	my $old = $_[0]{desc};
		325	$_[0]{desc} = $_[1] if @_ > 1;
		326	$old;
183	}	327	}
184		328
185	=back	329	=back
186		330
187	=cut	331	=cut
188		332
189	1;	333	1;
190		334
		335	=head1 BUGS/LIMITATIONS
		336
		337	- you must make very sure that no coro is still active on global
		338	destruction. very bad things might happen otherwise (usually segfaults).
		339
		340	- this module is not thread-safe. You should only ever use this module
		341	from the same thread (this requirement might be losened in the future
		342	to allow per-thread schedulers, but Coro::State does not yet allow
		343	this).
		344
		345	=head1 SEE ALSO
		346
		347	Support/Utility: L<Coro::Cont>, L<Coro::Specific>, L<Coro::State>, L<Coro::Util>.
		348
		349	Locking/IPC: L<Coro::Signal>, L<Coro::Channel>, L<Coro::Semaphore>, L<Coro::SemaphoreSet>, L<Coro::RWLock>.
		350
		351	Event/IO: L<Coro::Timer>, L<Coro::Event>, L<Coro::Handle>, L<Coro::Socket>, L<Coro::Select>.
		352
		353	Embedding: L<Coro:MakeMaker>
		354
191	=head1 AUTHOR	355	=head1 AUTHOR
192		356
193	Marc Lehmann <pcg@goof.com>	357	Marc Lehmann <schmorp@schmorp.de>
194	http://www.goof.com/pcg/marc/	358	http://home.schmorp.de/
195		359
196	=cut	360	=cut
197		361

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Comparing Coro/Coro.pm (file contents): Revision 1.8 by root, Sat Jul 14 22:14:21 2001 UTC vs. Revision 1.85 by root, Sat Nov 25 00:56:35 2006 UTC

Diff Legend

Comparing Coro/Coro.pm (file contents):
Revision 1.8 by root, Sat Jul 14 22:14:21 2001 UTC vs.
Revision 1.85 by root, Sat Nov 25 00:56:35 2006 UTC