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

Comparing Coro/Coro.pm (file contents):
Revision 1.34 by root, Sun Sep 16 01:34:35 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;
		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 = 0.5;	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;
119	my $manager = new Coro sub {	138	my $manager; $manager = new Coro sub {
120	while() {	139	while () {
121	delete ((pop @destroy)->{_coro_state}) while @destroy;	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	}
122	&schedule;	156	&schedule;
123	}	157	}
124	};	158	};
125		159
126	# static methods. not really.	160	# static methods. not really.
127		161
		162	=back
		163
128	=head2 STATIC METHODS	164	=head2 STATIC METHODS
129		165
130	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.
131		167
132	=over 4	168	=over 4
…		…
134	=item async { ... } [@args...]	170	=item async { ... } [@args...]
135		171
136	Create a new asynchronous process and return it's process object	172	Create a new asynchronous process and return it's process object
137	(usually unused). When the sub returns the new process is automatically	173	(usually unused). When the sub returns the new process is automatically
138	terminated.	174	terminated.
		175
		176	When the coroutine dies, the program will exit, just as in the main
		177	program.
139		178
140	# create a new coroutine that just prints its arguments	179	# create a new coroutine that just prints its arguments
141	async {	180	async {
142	print "@_\n";	181	print "@_\n";
143	} 1,2,3,4;	182	} 1,2,3,4;
144		183
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	184	=cut
149		185
150	sub async(&@) {	186	sub async(&@) {
151	my $pid = new Coro @_;	187	my $pid = new Coro @_;
152	$manager->ready; # this ensures that the stack is cloned from the manager
153	$pid->ready;	188	$pid->ready;
154	$pid;	189	$pid
155	}	190	}
156		191
157	=item schedule	192	=item schedule
158		193
159	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
…		…
168	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
169	current "timeslice" to other coroutines of the same or higher priority.	204	current "timeslice" to other coroutines of the same or higher priority.
170		205
171	=cut	206	=cut
172		207
173	=item terminate	208	=item terminate [arg...]
174		209
175	Terminates the current process.	210	Terminates the current process with the given status values (see L<cancel>).
176
177	Future versions of this function will allow result arguments.
178		211
179	=cut	212	=cut
180		213
181	sub terminate {	214	sub terminate {
182	$current->cancel;	215	$current->cancel (@_);
183	&schedule;
184	die; # NORETURN
185	}	216	}
186		217
187	=back	218	=back
188		219
189	# dynamic methods	220	# dynamic methods
…		…
195	=over 4	226	=over 4
196		227
197	=item new Coro \&sub [, @args...]	228	=item new Coro \&sub [, @args...]
198		229
199	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
200	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
201	the ready queue by calling the ready method.	233	by calling the ready method.
202		234
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	235	=cut
207		236
208	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;
209	terminate &{+shift};	241	terminate &{+shift};
210	}	242	}
211		243
212	sub new {	244	sub new {
213	my $class = shift;	245	my $class = shift;
214	bless {	246
215	_coro_state => (new Coro::State $_[0] && \&_newcoro, @_),	247	$class->SUPER::new (\&_new_coro, @_)
216	}, $class;
217	}	248	}
218		249
219	=item $process->ready	250	=item $process->ready
220		251
221	Put the current process into the ready queue.	252	Put the given process into the ready queue.
222		253
223	=cut	254	=cut
224		255
225	=item $process->cancel	256	=item $process->cancel (arg...)
226		257
227	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).
228		260
229	=cut	261	=cut
230		262
231	sub cancel {	263	sub cancel {
		264	my $self = shift;
		265	$self->{status} = [@_];
232	push @destroy, $_[0];	266	push @destroy, $self;
233	$manager->ready;	267	$manager->ready;
		268	&schedule if $current == $self;
234	}	269	}
235		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
236	=item $oldprio = $process->prio($newprio)	288	=item $oldprio = $process->prio ($newprio)
237		289
238	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
239	lower priority processes. Priorities are smalled signed integer (currently	292	processes. Priorities are small signed integers (currently -4 .. +3),
240	-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
241	tag :prio to get then):	294	to get then):
242		295
243	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
244	3 > 1 > 0 > -1 > -3 > -4	297	3 > 1 > 0 > -1 > -3 > -4
245		298
246	# set priority to HIGH	299	# set priority to HIGH
…		…
252	Changing the priority of the current process will take effect immediately,	305	Changing the priority of the current process will take effect immediately,
253	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
254	running) will only take effect after the next schedule (of that	307	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.	308	process). This is a bug that will be fixed in some future version.
256		309
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)	310	=item $newprio = $process->nice ($change)
266		311
267	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.
268	higher values mean lower priority, just as in unix).	313	higher values mean lower priority, just as in unix).
269		314
270	=cut	315	=item $olddesc = $process->desc ($newdesc)
271		316
272	sub nice {	317	Sets (or gets in case the argument is missing) the description for this
273	$_[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;
274	}	326	}
275		327
276	=back	328	=back
277		329
278	=cut	330	=cut
279		331
280	1;	332	1;
281		333
282	=head1 BUGS/LIMITATIONS	334	=head1 BUGS/LIMITATIONS
283		335
284	- 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
285	very bad things might happen otherwise (usually segfaults).	337	destruction. very bad things might happen otherwise (usually segfaults).
		338
286	- 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
287	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
288	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).
289		343
290	=head1 SEE ALSO	344	=head1 SEE ALSO
291		345
292	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>.
293	L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,	347
294	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>
295		353
296	=head1 AUTHOR	354	=head1 AUTHOR
297		355
298	Marc Lehmann <pcg@goof.com>	356	Marc Lehmann <schmorp@schmorp.de>
299	http://www.goof.com/pcg/marc/	357	http://home.schmorp.de/
300		358
301	=cut	359	=cut
302		360

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Comparing Coro/Coro.pm (file contents): Revision 1.34 by root, Sun Sep 16 01:34:35 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 1.34 by root, Sun Sep 16 01:34:35 2001 UTC vs.
Revision 1.86 by root, Sat Nov 25 01:14:11 2006 UTC