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

Comparing Coro/Coro.pm (file contents):
Revision 1.19 by root, Sat Jul 21 03:44:06 2001 UTC vs.
Revision 1.87 by root, Sun Nov 26 02:16:19 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
36	$VERSION = 0.09;	42	our $idle; # idle handler
		43	our $main; # main coroutine
		44	our $current; # current coroutine
37		45
		46	our $VERSION = '2.5';
		47
38	@EXPORT = qw(async yield schedule terminate current);	48	our @EXPORT = qw(async cede schedule terminate current);
39	@EXPORT_OK = qw($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, $ref, @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 (or as function: 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;
89		115
90	sub current() { $current }	116	sub current() { $current }
91		117
92	=item $idle	118	=item $idle
93		119
94	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
95	implementation prints "FATAL: deadlock detected" and exits.	121	to run. The default implementation prints "FATAL: deadlock detected" and
		122	exits.
96		123
97	=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.
98		127
99	# should be done using priorities :(	128	=cut
100	our $idle = new Coro sub {	129
		130	$idle = sub {
101	print STDERR "FATAL: deadlock detected\n";	131	print STDERR "FATAL: deadlock detected\n";
102	exit(51);	132	exit (51);
103	};	133	};
104		134
105	# we really need priorities...	135	# this coroutine is necessary because a coroutine
106	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	};
107		159
108	# static methods. not really.	160	# static methods. not really.
		161
		162	=back
109		163
110	=head2 STATIC METHODS	164	=head2 STATIC METHODS
111		165
112	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.
113		167
…		…
116	=item async { ... } [@args...]	170	=item async { ... } [@args...]
117		171
118	Create a new asynchronous process and return it's process object	172	Create a new asynchronous process and return it's process object
119	(usually unused). When the sub returns the new process is automatically	173	(usually unused). When the sub returns the new process is automatically
120	terminated.	174	terminated.
		175
		176	When the coroutine dies, the program will exit, just as in the main
		177	program.
121		178
122	# create a new coroutine that just prints its arguments	179	# create a new coroutine that just prints its arguments
123	async {	180	async {
124	print "@_\n";	181	print "@_\n";
125	} 1,2,3,4;	182	} 1,2,3,4;
126		183
127	The coderef you submit MUST NOT be a closure that refers to variables
128	in an outer scope. This does NOT work. Pass arguments into it instead.
129
130	=cut	184	=cut
131		185
132	sub async(&@) {	186	sub async(&@) {
133	my $pid = new Coro @_;	187	my $pid = new Coro @_;
134	$pid->ready;	188	$pid->ready;
135	$pid;	189	$pid
136	}	190	}
137		191
138	=item schedule	192	=item schedule
139		193
140	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
141	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
142	never be called again.	196	never be called again.
143		197
144	=cut	198	=cut
145		199
146	my $prev;
147
148	sub schedule {
149	# should be done using priorities :(
150	($prev, $current) = ($current, shift @ready \|\| $idle);
151	Coro::State::transfer($prev, $current);
152	}
153
154	=item yield	200	=item cede
155		201
156	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
157	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.
158		205
159	=cut	206	=cut
160		207
161	sub yield {
162	$current->ready;
163	&schedule;
164	}
165
166	=item terminate	208	=item terminate [arg...]
167		209
168	Terminates the current process.	210	Terminates the current process with the given status values (see L<cancel>).
169
170	Future versions of this function will allow result arguments.
171		211
172	=cut	212	=cut
173		213
174	sub terminate {	214	sub terminate {
175	$current->{_results} = [@_];	215	$current->cancel (@_);
176	&schedule;
177	}	216	}
178		217
179	=back	218	=back
180		219
181	# dynamic methods	220	# dynamic methods
…		…
187	=over 4	226	=over 4
188		227
189	=item new Coro \&sub [, @args...]	228	=item new Coro \&sub [, @args...]
190		229
191	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
192	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
193	the ready queue by calling the ready method.	233	by calling the ready method.
194		234
195	The coderef you submit MUST NOT be a closure that refers to variables
196	in an outer scope. This does NOT work. Pass arguments into it instead.
197
198	=cut	235	=cut
199		236
200	sub _newcoro {	237	sub _new_coro {
201	terminate &{+shift};	238	terminate &{+shift};
202	}	239	}
203		240
204	sub new {	241	sub new {
205	my $class = shift;	242	my $class = shift;
206	bless {	243
207	_coro_state => (new Coro::State $_[0] && \&_newcoro, @_),	244	$class->SUPER::new (\&_new_coro, @_)
208	}, $class;
209	}	245	}
210		246
211	=item $process->ready	247	=item $process->ready
212		248
213	Put the current process into the ready queue.	249	Put the given process into the ready queue.
214		250
215	=cut	251	=cut
216		252
217	sub ready {	253	=item $process->cancel (arg...)
218	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;
219	}	323	}
220		324
221	=back	325	=back
222		326
223	=cut	327	=cut
224		328
225	1;	329	1;
226		330
227	=head1 BUGS/LIMITATIONS	331	=head1 BUGS/LIMITATIONS
228		332
229	- could be faster, especially when the core would introduce special	333	- you must make very sure that no coro is still active on global
230	support for coroutines (like it does for threads).	334	destruction. very bad things might happen otherwise (usually segfaults).
231	- there is still a memleak on coroutine termination that I could not	335
232	identify. Could be as small as a single SV.
233	- this module is not well-tested.
234	- if variables or arguments "disappear" (become undef) or become
235	corrupted please contact the author so he cen iron out the
236	remaining bugs.
237	- this module is not thread-safe. You must only ever use this module from	336	- this module is not thread-safe. You should only ever use this module
238	the same thread (this requirement might be loosened in the future to	337	from the same thread (this requirement might be losened in the future
239	allow per-thread schedulers, but Coro::Satte does not yet allow this).	338	to allow per-thread schedulers, but Coro::State does not yet allow
		339	this).
240		340
241	=head1 SEE ALSO	341	=head1 SEE ALSO
242		342
243	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>.
244	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>
245		350
246	=head1 AUTHOR	351	=head1 AUTHOR
247		352
248	Marc Lehmann <pcg@goof.com>	353	Marc Lehmann <schmorp@schmorp.de>
249	http://www.goof.com/pcg/marc/	354	http://home.schmorp.de/
250		355
251	=cut	356	=cut
252		357

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Comparing Coro/Coro.pm (file contents): Revision 1.19 by root, Sat Jul 21 03:44:06 2001 UTC vs. Revision 1.87 by root, Sun Nov 26 02:16:19 2006 UTC

Diff Legend

Comparing Coro/Coro.pm (file contents):
Revision 1.19 by root, Sat Jul 21 03:44:06 2001 UTC vs.
Revision 1.87 by root, Sun Nov 26 02:16:19 2006 UTC