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

Comparing Coro/Coro.pm (file contents):
Revision 1.28 by root, Fri Aug 10 21:03:40 2001 UTC vs.
Revision 1.66 by root, Thu Mar 3 17:20:31 2005 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	+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
30	callchain, it's own set of lexicals and it's own set of perl's most	28	callchain, it's own set of lexicals and it's own set of perl's most
31	important global variables.	29	important global variables.
32		30
33	=cut	31	=cut
34		32
35	package Coro;	33	package Coro;
36		34
		35	BEGIN { eval { require warnings } && warnings->unimport ("uninitialized") }
		36
37	use Coro::State;	37	use Coro::State;
38		38
		39	use vars qw($idle $main $current);
		40
39	use base Exporter;	41	use base Exporter;
40		42
41	$VERSION = 0.13;	43	$VERSION = 1.11;
42		44
43	@EXPORT = qw(async cede schedule terminate current);	45	@EXPORT = qw(async cede schedule terminate current);
44	@EXPORT_OK = qw($current);	46	%EXPORT_TAGS = (
		47	prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],
		48	);
		49	@EXPORT_OK = @{$EXPORT_TAGS{prio}};
45		50
46	{	51	{
47	my @async;	52	my @async;
48	my $init;	53	my $init;
49		54
…		…
72	};	77	};
73	}	78	}
74		79
75	}	80	}
76		81
		82	=over 4
		83
77	=item $main	84	=item $main
78		85
79	This coroutine represents the main program.	86	This coroutine represents the main program.
80		87
81	=cut	88	=cut
82		89
83	our $main = new Coro;	90	$main = new Coro;
84		91
85	=item $current (or as function: current)	92	=item $current (or as function: current)
86		93
87	The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).	94	The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
88		95
…		…
91	# maybe some other module used Coro::Specific before...	98	# maybe some other module used Coro::Specific before...
92	if ($current) {	99	if ($current) {
93	$main->{specific} = $current->{specific};	100	$main->{specific} = $current->{specific};
94	}	101	}
95		102
96	our $current = $main;	103	$current = $main;
97		104
98	sub current() { $current }	105	sub current() { $current }
99		106
100	=item $idle	107	=item $idle
101		108
…		…
103	implementation prints "FATAL: deadlock detected" and exits.	110	implementation prints "FATAL: deadlock detected" and exits.
104		111
105	=cut	112	=cut
106		113
107	# should be done using priorities :(	114	# should be done using priorities :(
108	our $idle = new Coro sub {	115	$idle = new Coro sub {
109	print STDERR "FATAL: deadlock detected\n";	116	print STDERR "FATAL: deadlock detected\n";
110	exit(51);	117	exit(51);
111	};	118	};
112		119
113	# this coroutine is necessary because a coroutine	120	# this coroutine is necessary because a coroutine
114	# cannot destroy itself.	121	# cannot destroy itself.
115	my @destroy;	122	my @destroy;
		123	my $manager;
116	my $manager = new Coro sub {	124	$manager = new Coro sub {
117	while() {	125	while () {
118	delete ((pop @destroy)->{_coro_state}) while @destroy;	126	# by overwriting the state object with the manager we destroy it
		127	# while still being able to schedule this coroutine (in case it has
		128	# been readied multiple times. this is harmless since the manager
		129	# can be called as many times as neccessary and will always
		130	# remove itself from the runqueue
		131	while (@destroy) {
		132	my $coro = pop @destroy;
		133	$coro->{status} \|\|= [];
		134	$_->ready for @{delete $coro->{join} \|\| []};
		135
		136	# the next line destroys the _coro_state, but keeps the
		137	# process itself intact (we basically make it a zombie
		138	# process that always runs the manager thread, so it's possible
		139	# to transfer() to this process).
		140	$coro->{_coro_state} = $manager->{_coro_state};
		141	}
119	&schedule;	142	&schedule;
120	}	143	}
121	};	144	};
122		145
123	# we really need priorities...
124	my @ready; # the ready queue. hehe, rather broken ;)
125
126	# static methods. not really.	146	# static methods. not really.
		147
		148	=back
127		149
128	=head2 STATIC METHODS	150	=head2 STATIC METHODS
129		151
130	Static methods are actually functions that operate on the current process only.	152	Static methods are actually functions that operate on the current process only.
131		153
…		…
139		161
140	# create a new coroutine that just prints its arguments	162	# create a new coroutine that just prints its arguments
141	async {	163	async {
142	print "@_\n";	164	print "@_\n";
143	} 1,2,3,4;	165	} 1,2,3,4;
144
145	The coderef you submit MUST NOT be a closure that refers to variables
146	in an outer scope. This does NOT work. Pass arguments into it instead.
147		166
148	=cut	167	=cut
149		168
150	sub async(&@) {	169	sub async(&@) {
151	my $pid = new Coro @_;	170	my $pid = new Coro @_;
…		…
160	into the ready queue, so calling this function usually means you will	179	into the ready queue, so calling this function usually means you will
161	never be called again.	180	never be called again.
162		181
163	=cut	182	=cut
164		183
165	my $prev;
166
167	sub schedule {
168	# should be done using priorities :(
169	($prev, $current) = ($current, shift @ready \|\| $idle);
170	Coro::State::transfer($prev, $current);
171	}
172
173	=item cede	184	=item cede
174		185
175	"Cede" to other processes. This function puts the current process into the	186	"Cede" to other processes. This function puts the current process into the
176	ready queue and calls C<schedule>, which has the effect of giving up the	187	ready queue and calls C<schedule>, which has the effect of giving up the
177	current "timeslice" to other coroutines of the same or higher priority.	188	current "timeslice" to other coroutines of the same or higher priority.
178		189
179	=cut	190	=cut
180		191
181	sub cede {
182	$current->ready;
183	&schedule;
184	}
185
186	=item terminate	192	=item terminate [arg...]
187		193
188	Terminates the current process.	194	Terminates the current process with the given status values (see L<cancel>).
189
190	Future versions of this function will allow result arguments.
191		195
192	=cut	196	=cut
193		197
194	sub terminate {	198	sub terminate {
195	$current->cancel;	199	$current->cancel (@_);
196	&schedule;
197	die; # NORETURN
198	}	200	}
199		201
200	=back	202	=back
201		203
202	# dynamic methods	204	# dynamic methods
…		…
208	=over 4	210	=over 4
209		211
210	=item new Coro \&sub [, @args...]	212	=item new Coro \&sub [, @args...]
211		213
212	Create a new process and return it. When the sub returns the process	214	Create a new process and return it. When the sub returns the process
213	automatically terminates. To start the process you must first put it into	215	automatically terminates as if C<terminate> with the returned values were
		216	called. To make the process run you must first put it into the ready queue
214	the ready queue by calling the ready method.	217	by calling the ready method.
215
216	The coderef you submit MUST NOT be a closure that refers to variables
217	in an outer scope. This does NOT work. Pass arguments into it instead.
218		218
219	=cut	219	=cut
220		220
221	sub _newcoro {	221	sub _newcoro {
222	terminate &{+shift};	222	terminate &{+shift};
…		…
229	}, $class;	229	}, $class;
230	}	230	}
231		231
232	=item $process->ready	232	=item $process->ready
233		233
234	Put the current process into the ready queue.	234	Put the given process into the ready queue.
235		235
236	=cut	236	=cut
237		237
238	sub ready {
239	push @ready, $_[0];
240	}
241
242	=item $process->cancel	238	=item $process->cancel (arg...)
243		239
244	Like C<terminate>, but terminates the specified process instead.	240	Temrinates the given process and makes it return the given arguments as
		241	status (default: the empty list).
245		242
246	=cut	243	=cut
247		244
248	sub cancel {	245	sub cancel {
		246	my $self = shift;
		247	$self->{status} = [@_];
249	push @destroy, $_[0];	248	push @destroy, $self;
250	$manager->ready;	249	$manager->ready;
		250	&schedule if $current == $self;
		251	}
		252
		253	=item $process->join
		254
		255	Wait until the coroutine terminates and return any values given to the
		256	C<terminate> or C<cancel> functions. C<join> can be called multiple times
		257	from multiple processes.
		258
		259	=cut
		260
		261	sub join {
		262	my $self = shift;
		263	unless ($self->{status}) {
		264	push @{$self->{join}}, $current;
		265	&schedule;
		266	}
		267	wantarray ? @{$self->{status}} : $self->{status}[0];
		268	}
		269
		270	=item $oldprio = $process->prio($newprio)
		271
		272	Sets (or gets, if the argument is missing) the priority of the
		273	process. Higher priority processes get run before lower priority
		274	processes. Priorities are small signed integers (currently -4 .. +3),
		275	that you can refer to using PRIO_xxx constants (use the import tag :prio
		276	to get then):
		277
		278	PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
		279	3 > 1 > 0 > -1 > -3 > -4
		280
		281	# set priority to HIGH
		282	current->prio(PRIO_HIGH);
		283
		284	The idle coroutine ($Coro::idle) always has a lower priority than any
		285	existing coroutine.
		286
		287	Changing the priority of the current process will take effect immediately,
		288	but changing the priority of processes in the ready queue (but not
		289	running) will only take effect after the next schedule (of that
		290	process). This is a bug that will be fixed in some future version.
		291
		292	=cut
		293
		294	sub prio {
		295	my $old = $_[0]{prio};
		296	$_[0]{prio} = $_[1] if @_ > 1;
		297	$old;
		298	}
		299
		300	=item $newprio = $process->nice($change)
		301
		302	Similar to C<prio>, but subtract the given value from the priority (i.e.
		303	higher values mean lower priority, just as in unix).
		304
		305	=cut
		306
		307	sub nice {
		308	$_[0]{prio} -= $_[1];
		309	}
		310
		311	=item $olddesc = $process->desc($newdesc)
		312
		313	Sets (or gets in case the argument is missing) the description for this
		314	process. This is just a free-form string you can associate with a process.
		315
		316	=cut
		317
		318	sub desc {
		319	my $old = $_[0]{desc};
		320	$_[0]{desc} = $_[1] if @_ > 1;
		321	$old;
251	}	322	}
252		323
253	=back	324	=back
254		325
255	=cut	326	=cut
256		327
257	1;	328	1;
258		329
259	=head1 BUGS/LIMITATIONS	330	=head1 BUGS/LIMITATIONS
260		331
261	- could be faster, especially when the core would introduce special	332	- you must make very sure that no coro is still active on global
262	support for coroutines (like it does for threads).	333	destruction. very bad things might happen otherwise (usually segfaults).
263	- there is still a memleak on coroutine termination that I could not	334
264	identify. Could be as small as a single SV.
265	- this module is not well-tested.
266	- if variables or arguments "disappear" (become undef) or become
267	corrupted please contact the author so he cen iron out the
268	remaining bugs.
269	- this module is not thread-safe. You must only ever use this module from	335	- this module is not thread-safe. You should only ever use this module
270	the same thread (this requirement might be loosened in the future to	336	from the same thread (this requirement might be losened in the future
271	allow per-thread schedulers, but Coro::State does not yet allow this).	337	to allow per-thread schedulers, but Coro::State does not yet allow
		338	this).
272		339
273	=head1 SEE ALSO	340	=head1 SEE ALSO
274		341
275	L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,	342	L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
276	L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,	343	L<Coro::Signal>, L<Coro::State>, L<Coro::Timer>, L<Coro::Event>,
277	L<Coro::Handle>, L<Coro::Socket>.	344	L<Coro::Handle>, L<Coro::RWLock>, L<Coro::Socket>.
278		345
279	=head1 AUTHOR	346	=head1 AUTHOR
280		347
281	Marc Lehmann <pcg@goof.com>	348	Marc Lehmann <schmorp@schmorp.de>
282	http://www.goof.com/pcg/marc/	349	http://home.schmorp.de/
283		350
284	=cut	351	=cut
285		352

Diff Legend

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

Comparing Coro/Coro.pm (file contents): Revision 1.28 by root, Fri Aug 10 21:03:40 2001 UTC vs. Revision 1.66 by root, Thu Mar 3 17:20:31 2005 UTC

Diff Legend

Comparing Coro/Coro.pm (file contents):
Revision 1.28 by root, Fri Aug 10 21:03:40 2001 UTC vs.
Revision 1.66 by root, Thu Mar 3 17:20:31 2005 UTC