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

Comparing Coro/Coro.pm (file contents):
Revision 1.31 by root, Sat Aug 11 23:10:56 2001 UTC vs.
Revision 1.85 by root, Sat Nov 25 00:56:35 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;
		36	no warnings "uninitialized";
		37
37	use Coro::State;	38	use Coro::State;
38		39
39	use base Exporter;	40	use base qw(Coro::State Exporter);
40		41
		42	our $idle; # idle handler
		43	our $main; # main coroutine
		44	our $current; # current coroutine
		45
41	$VERSION = 0.45;	46	our $VERSION = '2.5';
42		47
43	@EXPORT = qw(async cede schedule terminate current);	48	our @EXPORT = qw(async cede schedule terminate current);
44	%EXPORT_TAGS = (	49	our %EXPORT_TAGS = (
45	prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],	50	prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],
46	);	51	);
47	@EXPORT_OK = @{$EXPORT_TAGS{prio}};	52	our @EXPORT_OK = @{$EXPORT_TAGS{prio}};
48		53
49	{	54	{
50	my @async;	55	my @async;
51	my $init;	56	my $init;
52		57
53	# this way of handling attributes simply is NOT scalable ;()	58	# this way of handling attributes simply is NOT scalable ;()
54	sub import {	59	sub import {
		60	no strict 'refs';
		61
55	Coro->export_to_level(1, @_);	62	Coro->export_to_level(1, @_);
		63
56	my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};	64	my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
57	*{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub {	65	*{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub {
58	my ($package, $ref) = (shift, shift);	66	my ($package, $ref) = (shift, shift);
59	my @attrs;	67	my @attrs;
60	for (@_) {	68	for (@_) {
…		…
75	};	83	};
76	}	84	}
77		85
78	}	86	}
79		87
		88	=over 4
		89
80	=item $main	90	=item $main
81		91
82	This coroutine represents the main program.	92	This coroutine represents the main program.
83		93
84	=cut	94	=cut
85		95
86	our $main = new Coro;	96	$main = new Coro;
87		97
88	=item $current (or as function: current)	98	=item $current (or as function: current)
89		99
90	The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).	100	The current coroutine (the last coroutine switched to). The initial value
		101	is C<$main> (of course).
		102
		103	This variable is B<strictly> I<read-only>. It is provided for performance
		104	reasons. If performance is not essentiel you are encouraged to use the
		105	C<Coro::current> function instead.
91		106
92	=cut	107	=cut
93		108
94	# maybe some other module used Coro::Specific before...	109	# maybe some other module used Coro::Specific before...
95	if ($current) {	110	if ($current) {
96	$main->{specific} = $current->{specific};	111	$main->{specific} = $current->{specific};
97	}	112	}
98		113
99	our $current = $main;	114	$current = $main;
100		115
101	sub current() { $current }	116	sub current() { $current }
102		117
103	=item $idle	118	=item $idle
104		119
105	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
106	implementation prints "FATAL: deadlock detected" and exits.	121	to run. The default implementation prints "FATAL: deadlock detected" and
		122	exits.
107		123
108	=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.
109		127
110	# should be done using priorities :(	128	=cut
111	our $idle = new Coro sub {	129
		130	$idle = sub {
112	print STDERR "FATAL: deadlock detected\n";	131	print STDERR "FATAL: deadlock detected\n";
113	exit(51);	132	exit (51);
114	};	133	};
115		134
116	# this coroutine is necessary because a coroutine	135	# this coroutine is necessary because a coroutine
117	# cannot destroy itself.	136	# cannot destroy itself.
118	my @destroy;	137	my @destroy;
		138	my $manager;
119	my $manager = new Coro sub {	139	$manager = new Coro sub {
120	while() {	140	while () {
121	delete ((pop @destroy)->{_coro_state}) while @destroy;	141	# by overwriting the state object with the manager we destroy it
		142	# while still being able to schedule this coroutine (in case it has
		143	# been readied multiple times. this is harmless since the manager
		144	# can be called as many times as neccessary and will always
		145	# remove itself from the runqueue
		146	while (@destroy) {
		147	my $coro = pop @destroy;
		148	$coro->{status} \|\|= [];
		149	$_->ready for @{delete $coro->{join} \|\| []};
		150
		151	# the next line destroys the coro state, but keeps the
		152	# process itself intact (we basically make it a zombie
		153	# process that always runs the manager thread, so it's possible
		154	# to transfer() to this process).
		155	$coro->_clone_state_from ($manager);
		156	}
122	&schedule;	157	&schedule;
123	}	158	}
124	};	159	};
125		160
126	# static methods. not really.	161	# static methods. not really.
127		162
		163	=back
		164
128	=head2 STATIC METHODS	165	=head2 STATIC METHODS
129		166
130	Static methods are actually functions that operate on the current process only.	167	Static methods are actually functions that operate on the current process only.
131		168
132	=over 4	169	=over 4
…		…
134	=item async { ... } [@args...]	171	=item async { ... } [@args...]
135		172
136	Create a new asynchronous process and return it's process object	173	Create a new asynchronous process and return it's process object
137	(usually unused). When the sub returns the new process is automatically	174	(usually unused). When the sub returns the new process is automatically
138	terminated.	175	terminated.
		176
		177	When the coroutine dies, the program will exit, just as in the main
		178	program.
139		179
140	# create a new coroutine that just prints its arguments	180	# create a new coroutine that just prints its arguments
141	async {	181	async {
142	print "@_\n";	182	print "@_\n";
143	} 1,2,3,4;	183	} 1,2,3,4;
144		184
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
148	=cut	185	=cut
149		186
150	sub async(&@) {	187	sub async(&@) {
151	my $pid = new Coro @_;	188	my $pid = new Coro @_;
152	$manager->ready; # this ensures that the stack is cloned from the manager
153	$pid->ready;	189	$pid->ready;
154	$pid;	190	$pid
155	}	191	}
156		192
157	=item schedule	193	=item schedule
158		194
159	Calls the scheduler. Please note that the current process will not be put	195	Calls the scheduler. Please note that the current process will not be put
…		…
168	ready queue and calls C<schedule>, which has the effect of giving up the	204	ready queue and calls C<schedule>, which has the effect of giving up the
169	current "timeslice" to other coroutines of the same or higher priority.	205	current "timeslice" to other coroutines of the same or higher priority.
170		206
171	=cut	207	=cut
172		208
173	=item terminate	209	=item terminate [arg...]
174		210
175	Terminates the current process.	211	Terminates the current process with the given status values (see L<cancel>).
176
177	Future versions of this function will allow result arguments.
178		212
179	=cut	213	=cut
180		214
181	sub terminate {	215	sub terminate {
182	$current->cancel;	216	$current->cancel (@_);
183	&schedule;
184	die; # NORETURN
185	}	217	}
186		218
187	=back	219	=back
188		220
189	# dynamic methods	221	# dynamic methods
…		…
195	=over 4	227	=over 4
196		228
197	=item new Coro \&sub [, @args...]	229	=item new Coro \&sub [, @args...]
198		230
199	Create a new process and return it. When the sub returns the process	231	Create a new process and return it. When the sub returns the process
200	automatically terminates. To start the process you must first put it into	232	automatically terminates as if C<terminate> with the returned values were
		233	called. To make the process run you must first put it into the ready queue
201	the ready queue by calling the ready method.	234	by calling the ready method.
202		235
203	The coderef you submit MUST NOT be a closure that refers to variables
204	in an outer scope. This does NOT work. Pass arguments into it instead.
205
206	=cut	236	=cut
207		237
208	sub _newcoro {	238	sub _new_coro {
		239	$current->_clear_idle_sp; # set the idle sp on the following cede
		240	_set_cede_self; # ensures that cede cede's us first
		241	cede;
209	terminate &{+shift};	242	terminate &{+shift};
210	}	243	}
211		244
212	sub new {	245	sub new {
213	my $class = shift;	246	my $class = shift;
214	bless {	247
215	_coro_state => (new Coro::State $_[0] && \&_newcoro, @_),	248	$class->SUPER::new (\&_new_coro, @_)
216	}, $class;
217	}	249	}
218		250
219	=item $process->ready	251	=item $process->ready
220		252
221	Put the current process into the ready queue.	253	Put the given process into the ready queue.
222		254
223	=cut	255	=cut
224		256
225	=item $process->cancel	257	=item $process->cancel (arg...)
226		258
227	Like C<terminate>, but terminates the specified process instead.	259	Terminates the given process and makes it return the given arguments as
		260	status (default: the empty list).
228		261
229	=cut	262	=cut
230		263
231	sub cancel {	264	sub cancel {
		265	my $self = shift;
		266	$self->{status} = [@_];
232	push @destroy, $_[0];	267	push @destroy, $self;
233	$manager->ready;	268	$manager->ready;
		269	&schedule if $current == $self;
234	}	270	}
235		271
		272	=item $process->join
		273
		274	Wait until the coroutine terminates and return any values given to the
		275	C<terminate> or C<cancel> functions. C<join> can be called multiple times
		276	from multiple processes.
		277
		278	=cut
		279
		280	sub join {
		281	my $self = shift;
		282	unless ($self->{status}) {
		283	push @{$self->{join}}, $current;
		284	&schedule;
		285	}
		286	wantarray ? @{$self->{status}} : $self->{status}[0];
		287	}
		288
236	=item $oldprio = $process->prio($newprio)	289	=item $oldprio = $process->prio ($newprio)
237		290
238	Sets the priority of the process. Higher priority processes get run before	291	Sets (or gets, if the argument is missing) the priority of the
		292	process. Higher priority processes get run before lower priority
239	lower priority processes. Priorities are smalled signed integer (currently	293	processes. Priorities are small signed integers (currently -4 .. +3),
240	-4 .. +3), that you can refer to using PRIO_xxx constants (use the import	294	that you can refer to using PRIO_xxx constants (use the import tag :prio
241	tag :prio to get then):	295	to get then):
242		296
243	PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN	297	PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
244	3 > 1 > 0 > -1 > -3 > -4	298	3 > 1 > 0 > -1 > -3 > -4
245		299
246	# set priority to HIGH	300	# set priority to HIGH
…		…
252	Changing the priority of the current process will take effect immediately,	306	Changing the priority of the current process will take effect immediately,
253	but changing the priority of processes in the ready queue (but not	307	but changing the priority of processes in the ready queue (but not
254	running) will only take effect after the next schedule (of that	308	running) will only take effect after the next schedule (of that
255	process). This is a bug that will be fixed in some future version.	309	process). This is a bug that will be fixed in some future version.
256		310
257	=cut
258
259	sub prio {
260	my $old = $_[0]{prio};
261	$_[0]{prio} = $_[1] if @_ > 1;
262	$old;
263	}
264
265	=item $newprio = $process->nice($change)	311	=item $newprio = $process->nice ($change)
266		312
267	Similar to C<prio>, but subtract the given value from the priority (i.e.	313	Similar to C<prio>, but subtract the given value from the priority (i.e.
268	higher values mean lower priority, just as in unix).	314	higher values mean lower priority, just as in unix).
269		315
270	=cut	316	=item $olddesc = $process->desc ($newdesc)
271		317
272	sub nice {	318	Sets (or gets in case the argument is missing) the description for this
273	$_[0]{prio} -= $_[1];	319	process. This is just a free-form string you can associate with a process.
		320
		321	=cut
		322
		323	sub desc {
		324	my $old = $_[0]{desc};
		325	$_[0]{desc} = $_[1] if @_ > 1;
		326	$old;
274	}	327	}
275		328
276	=back	329	=back
277		330
278	=cut	331	=cut
279		332
280	1;	333	1;
281		334
282	=head1 BUGS/LIMITATIONS	335	=head1 BUGS/LIMITATIONS
283		336
284	- could be faster, especially when the core would introduce special	337	- you must make very sure that no coro is still active on global
285	support for coroutines (like it does for threads).	338	destruction. very bad things might happen otherwise (usually segfaults).
286	- there is still a memleak on coroutine termination that I could not	339
287	identify. Could be as small as a single SV.
288	- this module is not well-tested.
289	- if variables or arguments "disappear" (become undef) or become
290	corrupted please contact the author so he cen iron out the
291	remaining bugs.
292	- this module is not thread-safe. You must only ever use this module from	340	- this module is not thread-safe. You should only ever use this module
293	the same thread (this requirement might be loosened in the future to	341	from the same thread (this requirement might be losened in the future
294	allow per-thread schedulers, but Coro::State does not yet allow this).	342	to allow per-thread schedulers, but Coro::State does not yet allow
		343	this).
295		344
296	=head1 SEE ALSO	345	=head1 SEE ALSO
297		346
298	L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,	347	Support/Utility: L<Coro::Cont>, L<Coro::Specific>, L<Coro::State>, L<Coro::Util>.
299	L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,	348
300	L<Coro::Handle>, L<Coro::Socket>.	349	Locking/IPC: L<Coro::Signal>, L<Coro::Channel>, L<Coro::Semaphore>, L<Coro::SemaphoreSet>, L<Coro::RWLock>.
		350
		351	Event/IO: L<Coro::Timer>, L<Coro::Event>, L<Coro::Handle>, L<Coro::Socket>, L<Coro::Select>.
		352
		353	Embedding: L<Coro:MakeMaker>
301		354
302	=head1 AUTHOR	355	=head1 AUTHOR
303		356
304	Marc Lehmann <pcg@goof.com>	357	Marc Lehmann <schmorp@schmorp.de>
305	http://www.goof.com/pcg/marc/	358	http://home.schmorp.de/
306		359
307	=cut	360	=cut
308		361

Diff Legend

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

Comparing Coro/Coro.pm (file contents): Revision 1.31 by root, Sat Aug 11 23:10:56 2001 UTC vs. Revision 1.85 by root, Sat Nov 25 00:56:35 2006 UTC

Diff Legend

Comparing Coro/Coro.pm (file contents):
Revision 1.31 by root, Sat Aug 11 23:10:56 2001 UTC vs.
Revision 1.85 by root, Sat Nov 25 00:56:35 2006 UTC