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

Comparing Coro/Coro.pm (file contents):
Revision 1.37 by root, Mon Sep 24 02:25:44 2001 UTC vs.
Revision 1.86 by root, Sat Nov 25 01:14:11 2006 UTC

…		…
19	cede;	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
26	This module is still experimental, see the BUGS section below.
27		25
28	In this module, coroutines are defined as "callchain + lexical variables	26	In this module, coroutines are defined as "callchain + lexical variables
29	+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own	27	+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
30	callchain, it's own set of lexicals and it's own set of perl's most	28	callchain, it's own set of lexicals and it's own set of perl's most
31	important global variables.	29	important global variables.
32		30
33	=cut	31	=cut
34		32
35	package Coro;	33	package Coro;
36		34
		35	use strict;
37	no warnings qw(uninitialized);	36	no warnings "uninitialized";
38		37
39	use Coro::State;	38	use Coro::State;
40		39
41	use base Exporter;	40	use base qw(Coro::State Exporter);
42		41
		42	our $idle; # idle handler
		43	our $main; # main coroutine
		44	our $current; # current coroutine
		45
43	$VERSION = 0.5;	46	our $VERSION = '2.5';
44		47
45	@EXPORT = qw(async cede schedule terminate current);	48	our @EXPORT = qw(async cede schedule terminate current);
46	%EXPORT_TAGS = (	49	our %EXPORT_TAGS = (
47	prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],	50	prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],
48	);	51	);
49	@EXPORT_OK = @{$EXPORT_TAGS{prio}};	52	our @EXPORT_OK = @{$EXPORT_TAGS{prio}};
50		53
51	{	54	{
52	my @async;	55	my @async;
53	my $init;	56	my $init;
54		57
55	# this way of handling attributes simply is NOT scalable ;()	58	# this way of handling attributes simply is NOT scalable ;()
56	sub import {	59	sub import {
		60	no strict 'refs';
		61
57	Coro->export_to_level(1, @_);	62	Coro->export_to_level(1, @_);
		63
58	my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};	64	my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
59	*{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub {	65	*{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub {
60	my ($package, $ref) = (shift, shift);	66	my ($package, $ref) = (shift, shift);
61	my @attrs;	67	my @attrs;
62	for (@_) {	68	for (@_) {
…		…
77	};	83	};
78	}	84	}
79		85
80	}	86	}
81		87
		88	=over 4
		89
82	=item $main	90	=item $main
83		91
84	This coroutine represents the main program.	92	This coroutine represents the main program.
85		93
86	=cut	94	=cut
87		95
88	our $main = new Coro;	96	$main = new Coro;
89		97
90	=item $current (or as function: current)	98	=item $current (or as function: current)
91		99
92	The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).	100	The current coroutine (the last coroutine switched to). The initial value
		101	is C<$main> (of course).
		102
		103	This variable is B<strictly> I<read-only>. It is provided for performance
		104	reasons. If performance is not essentiel you are encouraged to use the
		105	C<Coro::current> function instead.
93		106
94	=cut	107	=cut
95		108
96	# maybe some other module used Coro::Specific before...	109	# maybe some other module used Coro::Specific before...
97	if ($current) {	110	if ($current) {
98	$main->{specific} = $current->{specific};	111	$main->{specific} = $current->{specific};
99	}	112	}
100		113
101	our $current = $main;	114	$current = $main;
102		115
103	sub current() { $current }	116	sub current() { $current }
104		117
105	=item $idle	118	=item $idle
106		119
107	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
108	implementation prints "FATAL: deadlock detected" and exits.	121	to run. The default implementation prints "FATAL: deadlock detected" and
		122	exits.
109		123
110	=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.
111		127
112	# should be done using priorities :(	128	=cut
113	our $idle = new Coro sub {	129
		130	$idle = sub {
114	print STDERR "FATAL: deadlock detected\n";	131	print STDERR "FATAL: deadlock detected\n";
115	exit(51);	132	exit (51);
116	};	133	};
117		134
118	# this coroutine is necessary because a coroutine	135	# this coroutine is necessary because a coroutine
119	# cannot destroy itself.	136	# cannot destroy itself.
120	my @destroy;	137	my @destroy;
121	my $manager = new Coro sub {	138	my $manager; $manager = new Coro sub {
122	while() {	139	while () {
123	# by overwriting the state object with the manager we destroy it	140	# by overwriting the state object with the manager we destroy it
124	# while still being able to schedule this coroutine (in case it has	141	# while still being able to schedule this coroutine (in case it has
125	# been readied multiple times. this is harmless since the manager	142	# been readied multiple times. this is harmless since the manager
126	# can be called as many times as neccessary and will always	143	# can be called as many times as neccessary and will always
127	# remove itself from the runqueue	144	# remove itself from the runqueue
128	(pop @destroy)->{_coro_state} = $manager->{_coro_state} while @destroy;	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	}
129	&schedule;	156	&schedule;
130	}	157	}
131	};	158	};
132		159
133	# static methods. not really.	160	# static methods. not really.
134		161
		162	=back
		163
135	=head2 STATIC METHODS	164	=head2 STATIC METHODS
136		165
137	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.
138		167
139	=over 4	168	=over 4
…		…
141	=item async { ... } [@args...]	170	=item async { ... } [@args...]
142		171
143	Create a new asynchronous process and return it's process object	172	Create a new asynchronous process and return it's process object
144	(usually unused). When the sub returns the new process is automatically	173	(usually unused). When the sub returns the new process is automatically
145	terminated.	174	terminated.
		175
		176	When the coroutine dies, the program will exit, just as in the main
		177	program.
146		178
147	# create a new coroutine that just prints its arguments	179	# create a new coroutine that just prints its arguments
148	async {	180	async {
149	print "@_\n";	181	print "@_\n";
150	} 1,2,3,4;	182	} 1,2,3,4;
151		183
152	The coderef you submit MUST NOT be a closure that refers to variables
153	in an outer scope. This does NOT work. Pass arguments into it instead.
154
155	=cut	184	=cut
156		185
157	sub async(&@) {	186	sub async(&@) {
158	my $pid = new Coro @_;	187	my $pid = new Coro @_;
159	$manager->ready; # this ensures that the stack is cloned from the manager
160	$pid->ready;	188	$pid->ready;
161	$pid;	189	$pid
162	}	190	}
163		191
164	=item schedule	192	=item schedule
165		193
166	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
…		…
175	ready queue and calls C<schedule>, which has the effect of giving up the	203	ready queue and calls C<schedule>, which has the effect of giving up the
176	current "timeslice" to other coroutines of the same or higher priority.	204	current "timeslice" to other coroutines of the same or higher priority.
177		205
178	=cut	206	=cut
179		207
180	=item terminate	208	=item terminate [arg...]
181		209
182	Terminates the current process.	210	Terminates the current process with the given status values (see L<cancel>).
183
184	Future versions of this function will allow result arguments.
185		211
186	=cut	212	=cut
187		213
188	sub terminate {	214	sub terminate {
189	$current->cancel;	215	$current->cancel (@_);
190	&schedule;
191	die; # NORETURN
192	}	216	}
193		217
194	=back	218	=back
195		219
196	# dynamic methods	220	# dynamic methods
…		…
202	=over 4	226	=over 4
203		227
204	=item new Coro \&sub [, @args...]	228	=item new Coro \&sub [, @args...]
205		229
206	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
207	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
208	the ready queue by calling the ready method.	233	by calling the ready method.
209		234
210	The coderef you submit MUST NOT be a closure that refers to variables
211	in an outer scope. This does NOT work. Pass arguments into it instead.
212
213	=cut	235	=cut
214		236
215	sub _newcoro {	237	sub _new_coro {
		238	$current->_clear_idle_sp; # (re-)set the idle sp on the following cede
		239	_set_cede_self; # ensures that cede cede's us first
		240	cede;
216	terminate &{+shift};	241	terminate &{+shift};
217	}	242	}
218		243
219	sub new {	244	sub new {
220	my $class = shift;	245	my $class = shift;
221	bless {	246
222	_coro_state => (new Coro::State $_[0] && \&_newcoro, @_),	247	$class->SUPER::new (\&_new_coro, @_)
223	}, $class;
224	}	248	}
225		249
226	=item $process->ready	250	=item $process->ready
227		251
228	Put the current process into the ready queue.	252	Put the given process into the ready queue.
229		253
230	=cut	254	=cut
231		255
232	=item $process->cancel	256	=item $process->cancel (arg...)
233		257
234	Like C<terminate>, but terminates the specified process instead.	258	Terminates the given process and makes it return the given arguments as
		259	status (default: the empty list).
235		260
236	=cut	261	=cut
237		262
238	sub cancel {	263	sub cancel {
		264	my $self = shift;
		265	$self->{status} = [@_];
239	push @destroy, $_[0];	266	push @destroy, $self;
240	$manager->ready;	267	$manager->ready;
241	&schedule if $current == $_[0];	268	&schedule if $current == $self;
242	}	269	}
243		270
		271	=item $process->join
		272
		273	Wait until the coroutine terminates and return any values given to the
		274	C<terminate> or C<cancel> functions. C<join> can be called multiple times
		275	from multiple processes.
		276
		277	=cut
		278
		279	sub join {
		280	my $self = shift;
		281	unless ($self->{status}) {
		282	push @{$self->{join}}, $current;
		283	&schedule;
		284	}
		285	wantarray ? @{$self->{status}} : $self->{status}[0];
		286	}
		287
244	=item $oldprio = $process->prio($newprio)	288	=item $oldprio = $process->prio ($newprio)
245		289
246	Sets the priority of the process. Higher priority processes get run before	290	Sets (or gets, if the argument is missing) the priority of the
		291	process. Higher priority processes get run before lower priority
247	lower priority processes. Priorities are smalled signed integer (currently	292	processes. Priorities are small signed integers (currently -4 .. +3),
248	-4 .. +3), that you can refer to using PRIO_xxx constants (use the import	293	that you can refer to using PRIO_xxx constants (use the import tag :prio
249	tag :prio to get then):	294	to get then):
250		295
251	PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN	296	PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
252	3 > 1 > 0 > -1 > -3 > -4	297	3 > 1 > 0 > -1 > -3 > -4
253		298
254	# set priority to HIGH	299	# set priority to HIGH
…		…
260	Changing the priority of the current process will take effect immediately,	305	Changing the priority of the current process will take effect immediately,
261	but changing the priority of processes in the ready queue (but not	306	but changing the priority of processes in the ready queue (but not
262	running) will only take effect after the next schedule (of that	307	running) will only take effect after the next schedule (of that
263	process). This is a bug that will be fixed in some future version.	308	process). This is a bug that will be fixed in some future version.
264		309
265	=cut
266
267	sub prio {
268	my $old = $_[0]{prio};
269	$_[0]{prio} = $_[1] if @_ > 1;
270	$old;
271	}
272
273	=item $newprio = $process->nice($change)	310	=item $newprio = $process->nice ($change)
274		311
275	Similar to C<prio>, but subtract the given value from the priority (i.e.	312	Similar to C<prio>, but subtract the given value from the priority (i.e.
276	higher values mean lower priority, just as in unix).	313	higher values mean lower priority, just as in unix).
277		314
278	=cut	315	=item $olddesc = $process->desc ($newdesc)
279		316
280	sub nice {	317	Sets (or gets in case the argument is missing) the description for this
281	$_[0]{prio} -= $_[1];	318	process. This is just a free-form string you can associate with a process.
		319
		320	=cut
		321
		322	sub desc {
		323	my $old = $_[0]{desc};
		324	$_[0]{desc} = $_[1] if @_ > 1;
		325	$old;
282	}	326	}
283		327
284	=back	328	=back
285		329
286	=cut	330	=cut
287		331
288	1;	332	1;
289		333
290	=head1 BUGS/LIMITATIONS	334	=head1 BUGS/LIMITATIONS
291		335
292	- you must make very sure that no coro is still active on global destruction.	336	- you must make very sure that no coro is still active on global
293	very bad things might happen otherwise (usually segfaults).	337	destruction. very bad things might happen otherwise (usually segfaults).
		338
294	- this module is not thread-safe. You must only ever use this module from	339	- this module is not thread-safe. You should only ever use this module
295	the same thread (this requirement might be loosened in the future to	340	from the same thread (this requirement might be losened in the future
296	allow per-thread schedulers, but Coro::State does not yet allow this).	341	to allow per-thread schedulers, but Coro::State does not yet allow
		342	this).
297		343
298	=head1 SEE ALSO	344	=head1 SEE ALSO
299		345
300	L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,	346	Support/Utility: L<Coro::Cont>, L<Coro::Specific>, L<Coro::State>, L<Coro::Util>.
301	L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,	347
302	L<Coro::Handle>, L<Coro::Socket>.	348	Locking/IPC: L<Coro::Signal>, L<Coro::Channel>, L<Coro::Semaphore>, L<Coro::SemaphoreSet>, L<Coro::RWLock>.
		349
		350	Event/IO: L<Coro::Timer>, L<Coro::Event>, L<Coro::Handle>, L<Coro::Socket>, L<Coro::Select>.
		351
		352	Embedding: L<Coro:MakeMaker>
303		353
304	=head1 AUTHOR	354	=head1 AUTHOR
305		355
306	Marc Lehmann <pcg@goof.com>	356	Marc Lehmann <schmorp@schmorp.de>
307	http://www.goof.com/pcg/marc/	357	http://home.schmorp.de/
308		358
309	=cut	359	=cut
310		360

Diff Legend

-–
+Removed lines
-+
+Added lines
-<
+Changed lines
->
+Changed lines

Comparing Coro/Coro.pm (file contents): Revision 1.37 by root, Mon Sep 24 02:25:44 2001 UTC vs. Revision 1.86 by root, Sat Nov 25 01:14:11 2006 UTC

Diff Legend

Comparing Coro/Coro.pm (file contents):
Revision 1.37 by root, Mon Sep 24 02:25:44 2001 UTC vs.
Revision 1.86 by root, Sat Nov 25 01:14:11 2006 UTC