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

Comparing Coro/Coro.pm (file contents):
Revision 1.14 by root, Tue Jul 17 02:21:56 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	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		25
26	This module is still experimental, see the BUGS section below.	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.
27		30
28	=cut	31	=cut
29		32
30	package Coro;	33	package Coro;
31		34
		35	use strict;
		36	no warnings "uninitialized";
		37
32	use Coro::State;	38	use Coro::State;
33		39
34	use base Exporter;	40	use base qw(Coro::State Exporter);
35		41
		42	our $idle; # idle handler
		43	our $main; # main coroutine
		44	our $current; # current coroutine
		45
36	$VERSION = 0.05;	46	our $VERSION = '3.0';
37		47
38	@EXPORT = qw(async yield schedule terminate);	48	our @EXPORT = qw(async cede schedule terminate current);
39	@EXPORT_OK = qw($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}};
40		53
41	{	54	{
42	use subs 'async';
43
44	my @async;	55	my @async;
		56	my $init;
45		57
46	# this way of handling attributes simply is NOT scalable ;()	58	# this way of handling attributes simply is NOT scalable ;()
47	sub import {	59	sub import {
		60	no strict 'refs';
		61
48	Coro->export_to_level(1, @_);	62	Coro->export_to_level(1, @_);
		63
49	my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};	64	my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
50	*{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub {	65	*{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub {
51	my ($package, $ref) = (shift, shift);	66	my ($package, $ref) = (shift, shift);
52	my @attrs;	67	my @attrs;
53	for (@_) {	68	for (@_) {
54	if ($_ eq "Coro") {	69	if ($_ eq "Coro") {
55	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	}
56	} else {	78	} else {
57	push @attrs, @_;	79	push @attrs, $_;
58	}	80	}
59	}	81	}
60	return $old ? $old->($package, $name, @attrs) : @attrs;	82	return $old ? $old->($package, $ref, @attrs) : @attrs;
61	};	83	};
62	}	84	}
63		85
64	sub INIT {
65	async pop @async while @async;
66	}
67	}	86	}
		87
		88	=over 4
68		89
69	=item $main	90	=item $main
70		91
71	This coroutine represents the main program.	92	This coroutine represents the main program.
72		93
73	=cut	94	=cut
74		95
75	our $main = new Coro;	96	$main = new Coro;
76		97
77	=item $current	98	=item $current (or as function: current)
78		99
79	The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).	100	The current coroutine (the last coroutine switched to). The initial value
		101	is C<$main> (of course).
		102
		103	This variable is B<strictly> I<read-only>. It is provided for performance
		104	reasons. If performance is not essentiel you are encouraged to use the
		105	C<Coro::current> function instead.
80		106
81	=cut	107	=cut
82		108
83	# maybe some other module used Coro::Specific before...	109	# maybe some other module used Coro::Specific before...
84	if ($current) {	110	if ($current) {
85	$main->{specific} = $current->{specific};	111	$main->{specific} = $current->{specific};
86	}	112	}
87		113
88	our $current = $main;	114	$current = $main;
		115
		116	sub current() { $current }
89		117
90	=item $idle	118	=item $idle
91		119
92	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
93	implementation prints "FATAL: deadlock detected" and exits.	121	to run. The default implementation prints "FATAL: deadlock detected" and
		122	exits.
94		123
95	=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.
96		127
97	# should be done using priorities :(	128	=cut
98	our $idle = new Coro sub {	129
		130	$idle = sub {
99	print STDERR "FATAL: deadlock detected\n";	131	print STDERR "FATAL: deadlock detected\n";
100	exit(51);	132	exit (51);
101	};	133	};
102		134
103	# we really need priorities...	135	# this coroutine is necessary because a coroutine
104	## my @ready; #d#	136	# cannot destroy itself.
105	our @ready = (); # the ready queue. hehe, rather broken ;)	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	};
106		159
107	# static methods. not really.	160	# static methods. not really.
		161
		162	=back
108		163
109	=head2 STATIC METHODS	164	=head2 STATIC METHODS
110		165
111	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.
112		167
…		…
115	=item async { ... } [@args...]	170	=item async { ... } [@args...]
116		171
117	Create a new asynchronous process and return it's process object	172	Create a new asynchronous process and return it's process object
118	(usually unused). When the sub returns the new process is automatically	173	(usually unused). When the sub returns the new process is automatically
119	terminated.	174	terminated.
		175
		176	When the coroutine dies, the program will exit, just as in the main
		177	program.
120		178
121	# create a new coroutine that just prints its arguments	179	# create a new coroutine that just prints its arguments
122	async {	180	async {
123	print "@_\n";	181	print "@_\n";
124	} 1,2,3,4;	182	} 1,2,3,4;
125		183
126	The coderef you submit MUST NOT be a closure that refers to variables
127	in an outer scope. This does NOT work. Pass arguments into it instead.
128
129	=cut	184	=cut
130		185
131	sub async(&@) {	186	sub async(&@) {
132	my $pid = new Coro @_;	187	my $pid = new Coro @_;
133	$pid->ready;	188	$pid->ready;
134	$pid;	189	$pid
135	}	190	}
136		191
137	=item schedule	192	=item schedule
138		193
139	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
140	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
141	never be called again.	196	never be called again.
142		197
143	=cut	198	=cut
144		199
145	my $prev;
146
147	sub schedule {
148	# should be done using priorities :(
149	($prev, $current) = ($current, shift @ready \|\| $idle);
150	Coro::State::transfer($prev, $current);
151	}
152
153	=item yield	200	=item cede
154		201
155	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
156	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.
157		205
158	=cut	206	=cut
159		207
160	sub yield {
161	$current->ready;
162	&schedule;
163	}
164
165	=item terminate	208	=item terminate [arg...]
166		209
167	Terminates the current process.	210	Terminates the current process with the given status values (see L<cancel>).
168
169	Future versions of this function will allow result arguments.
170		211
171	=cut	212	=cut
172		213
173	sub terminate {	214	sub terminate {
174	$current->{_results} = [@_];	215	$current->cancel (@_);
175	&schedule;
176	}	216	}
177		217
178	=back	218	=back
179		219
180	# dynamic methods	220	# dynamic methods
…		…
186	=over 4	226	=over 4
187		227
188	=item new Coro \&sub [, @args...]	228	=item new Coro \&sub [, @args...]
189		229
190	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
191	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
192	the ready queue by calling the ready method.	233	by calling the ready method.
193		234
194	The coderef you submit MUST NOT be a closure that refers to variables
195	in an outer scope. This does NOT work. Pass arguments into it instead.
196
197	=cut	235	=cut
198		236
199	sub _newcoro {	237	sub _new_coro {
200	terminate &{+shift};	238	terminate &{+shift};
201	}	239	}
202		240
203	sub new {	241	sub new {
204	my $class = shift;	242	my $class = shift;
205	bless {	243
206	_coro_state => (new Coro::State $_[0] && \&_newcoro, @_),	244	$class->SUPER::new (\&_new_coro, @_)
207	}, $class;
208	}	245	}
209		246
210	=item $process->ready	247	=item $process->ready
211		248
212	Put the current process into the ready queue.	249	Put the given process into the ready queue.
213		250
214	=cut	251	=cut
215		252
216	sub ready {	253	=item $process->cancel (arg...)
217	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;
218	}	323	}
219		324
220	=back	325	=back
221		326
222	=cut	327	=cut
223		328
224	1;	329	1;
225		330
226	=head1 BUGS	331	=head1 BUGS/LIMITATIONS
227		332
228	- could be faster, especially when the core would introduce special	333	- you must make very sure that no coro is still active on global
229	support for coroutines (like it does for threads).	334	destruction. very bad things might happen otherwise (usually segfaults).
230	- there is still a memleak on coroutine termination that I could not	335
231	identify. Could be as small as a single SV.	336	- this module is not thread-safe. You should only ever use this module
232	- this module is not well-tested.	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).
233		340
234	=head1 SEE ALSO	341	=head1 SEE ALSO
235		342
236	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>.
237	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>
238		350
239	=head1 AUTHOR	351	=head1 AUTHOR
240		352
241	Marc Lehmann <pcg@goof.com>	353	Marc Lehmann <schmorp@schmorp.de>
242	http://www.goof.com/pcg/marc/	354	http://home.schmorp.de/
243		355
244	=cut	356	=cut
245		357

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Comparing Coro/Coro.pm (file contents): Revision 1.14 by root, Tue Jul 17 02:21:56 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 1.14 by root, Tue Jul 17 02:21:56 2001 UTC vs.
Revision 1.88 by root, Sun Nov 26 02:54:55 2006 UTC