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

Comparing Coro/Coro.pm (file contents):
Revision 1.11 by root, Sun Jul 15 03:24:18 2001 UTC vs.
Revision 1.90 by root, Thu Nov 30 18:21:14 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	Calling C<exit> in a coroutine will not work correctly, so do not do that.
116		177
		178	When the coroutine dies, the program will exit, just as in the main
		179	program.
		180
		181	# create a new coroutine that just prints its arguments
		182	async {
		183	print "@_\n";
		184	} 1,2,3,4;
		185
		186	=cut
		187
117	sub async(&) {	188	sub async(&@) {
118	my $pid = new Coro $_[0];	189	my $pid = new Coro @_;
119	$pid->ready;	190	$pid->ready;
120	$pid;	191	$pid
121	}	192	}
122		193
123	=item schedule	194	=item schedule
124		195
125	Calls the scheduler. Please note that the current process will not be put	196	Calls the scheduler. Please note that the current process will not be put
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 $prev;
132
133	sub schedule {
134	# should be done using priorities :(
135	($prev, $current) = ($current, shift @ready \|\| $idle);
136	Coro::State::transfer($prev, $current);
137	}
138
139	=item yield	202	=item cede
140		203
141	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
142	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.
143		207
144	=cut	208	=cut
145		209
146	sub yield {
147	$current->ready;
148	&schedule;
149	}
150
151	=item terminate	210	=item terminate [arg...]
152		211
153	Terminates the current process.	212	Terminates the current process with the given status values (see L<cancel>).
154		213
155	=cut	214	=cut
156		215
157	sub terminate {	216	sub terminate {
158	&schedule;	217	$current->cancel (@_);
159	}	218	}
160		219
161	=back	220	=back
162		221
163	# dynamic methods	222	# dynamic methods
…		…
166		225
167	These are the methods you can call on process objects.	226	These are the methods you can call on process objects.
168		227
169	=over 4	228	=over 4
170		229
171	=item new Coro \⊂	230	=item new Coro \&sub [, @args...]
172		231
173	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
174	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
175	the ready queue by calling the ready method.	235	by calling the ready method.
176		236
		237	Calling C<exit> in a coroutine will not work correctly, so do not do that.
		238
177	=cut	239	=cut
		240
		241	sub _new_coro {
		242	terminate &{+shift};
		243	}
178		244
179	sub new {	245	sub new {
180	my $class = shift;	246	my $class = shift;
181	my $proc = $_[0];
182	bless {
183	_coro_state => new Coro::State ($proc ? sub { &$proc; &terminate } : $proc),
184	}, $class;
185	}
186		247
		248	$class->SUPER::new (\&_new_coro, @_)
		249	}
		250
187	=item $process->ready	251	=item $success = $process->ready
188		252
189	Put the current process into the ready queue.	253	Put the given process into the ready queue (according to it's priority)
		254	and return true. If the process is already in the ready queue, do nothing
		255	and return false.
190		256
191	=cut	257	=item $is_ready = $process->is_ready
192		258
193	sub ready {	259	Return wether the process is currently the ready queue or not,
194	push @ready, $_[0];	260
		261	=item $process->cancel (arg...)
		262
		263	Terminates the given process and makes it return the given arguments as
		264	status (default: the empty list).
		265
		266	=cut
		267
		268	sub cancel {
		269	my $self = shift;
		270	$self->{status} = [@_];
		271	push @destroy, $self;
		272	$manager->ready;
		273	&schedule if $current == $self;
		274	}
		275
		276	=item $process->join
		277
		278	Wait until the coroutine terminates and return any values given to the
		279	C<terminate> or C<cancel> functions. C<join> can be called multiple times
		280	from multiple processes.
		281
		282	=cut
		283
		284	sub join {
		285	my $self = shift;
		286	unless ($self->{status}) {
		287	push @{$self->{join}}, $current;
		288	&schedule;
		289	}
		290	wantarray ? @{$self->{status}} : $self->{status}[0];
		291	}
		292
		293	=item $oldprio = $process->prio ($newprio)
		294
		295	Sets (or gets, if the argument is missing) the priority of the
		296	process. Higher priority processes get run before lower priority
		297	processes. Priorities are small signed integers (currently -4 .. +3),
		298	that you can refer to using PRIO_xxx constants (use the import tag :prio
		299	to get then):
		300
		301	PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
		302	3 > 1 > 0 > -1 > -3 > -4
		303
		304	# set priority to HIGH
		305	current->prio(PRIO_HIGH);
		306
		307	The idle coroutine ($Coro::idle) always has a lower priority than any
		308	existing coroutine.
		309
		310	Changing the priority of the current process will take effect immediately,
		311	but changing the priority of processes in the ready queue (but not
		312	running) will only take effect after the next schedule (of that
		313	process). This is a bug that will be fixed in some future version.
		314
		315	=item $newprio = $process->nice ($change)
		316
		317	Similar to C<prio>, but subtract the given value from the priority (i.e.
		318	higher values mean lower priority, just as in unix).
		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;
195	}	331	}
196		332
197	=back	333	=back
198		334
199	=cut	335	=cut
200		336
201	1;	337	1;
202		338
		339	=head1 BUGS/LIMITATIONS
		340
		341	- you must make very sure that no coro is still active on global
		342	destruction. very bad things might happen otherwise (usually segfaults).
		343
		344	- this module is not thread-safe. You should only ever use this module
		345	from the same thread (this requirement might be losened in the future
		346	to allow per-thread schedulers, but Coro::State does not yet allow
		347	this).
		348
203	=head1 SEE ALSO	349	=head1 SEE ALSO
204		350
205	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>.
206	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>
207		358
208	=head1 AUTHOR	359	=head1 AUTHOR
209		360
210	Marc Lehmann <pcg@goof.com>	361	Marc Lehmann <schmorp@schmorp.de>
211	http://www.goof.com/pcg/marc/	362	http://home.schmorp.de/
212		363
213	=cut	364	=cut
214		365

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Comparing Coro/Coro.pm (file contents): Revision 1.11 by root, Sun Jul 15 03:24:18 2001 UTC vs. Revision 1.90 by root, Thu Nov 30 18:21:14 2006 UTC

Diff Legend

Comparing Coro/Coro.pm (file contents):
Revision 1.11 by root, Sun Jul 15 03:24:18 2001 UTC vs.
Revision 1.90 by root, Thu Nov 30 18:21:14 2006 UTC