[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 1.85 by root, Sat Nov 25 00:56:35 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;
		139	$manager = new Coro sub {
		140	while () {
		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	}
		157	&schedule;
		158	}
		159	};
107		160
108	# static methods. not really.	161	# static methods. not really.
		162
		163	=back
109		164
110	=head2 STATIC METHODS	165	=head2 STATIC METHODS
111		166
112	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.
113		168
…		…
116	=item async { ... } [@args...]	171	=item async { ... } [@args...]
117		172
118	Create a new asynchronous process and return it's process object	173	Create a new asynchronous process and return it's process object
119	(usually unused). When the sub returns the new process is automatically	174	(usually unused). When the sub returns the new process is automatically
120	terminated.	175	terminated.
		176
		177	When the coroutine dies, the program will exit, just as in the main
		178	program.
121		179
122	# create a new coroutine that just prints its arguments	180	# create a new coroutine that just prints its arguments
123	async {	181	async {
124	print "@_\n";	182	print "@_\n";
125	} 1,2,3,4;	183	} 1,2,3,4;
126		184
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	185	=cut
131		186
132	sub async(&@) {	187	sub async(&@) {
133	my $pid = new Coro @_;	188	my $pid = new Coro @_;
134	$pid->ready;	189	$pid->ready;
135	$pid;	190	$pid
136	}	191	}
137		192
138	=item schedule	193	=item schedule
139		194
140	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
141	into the ready queue, so calling this function usually means you will	196	into the ready queue, so calling this function usually means you will
142	never be called again.	197	never be called again.
143		198
144	=cut	199	=cut
145		200
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	201	=item cede
155		202
156	Yield to other processes. This function puts the current process into the	203	"Cede" to other processes. This function puts the current process into the
157	ready queue and calls C<schedule>.	204	ready queue and calls C<schedule>, which has the effect of giving up the
		205	current "timeslice" to other coroutines of the same or higher priority.
158		206
159	=cut	207	=cut
160		208
161	sub yield {
162	$current->ready;
163	&schedule;
164	}
165
166	=item terminate	209	=item terminate [arg...]
167		210
168	Terminates the current process.	211	Terminates the current process with the given status values (see L<cancel>).
169
170	Future versions of this function will allow result arguments.
171		212
172	=cut	213	=cut
173		214
174	sub terminate {	215	sub terminate {
175	$current->{_results} = [@_];	216	$current->cancel (@_);
176	&schedule;
177	}	217	}
178		218
179	=back	219	=back
180		220
181	# dynamic methods	221	# dynamic methods
…		…
187	=over 4	227	=over 4
188		228
189	=item new Coro \&sub [, @args...]	229	=item new Coro \&sub [, @args...]
190		230
191	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
192	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
193	the ready queue by calling the ready method.	234	by calling the ready method.
194		235
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	236	=cut
199		237
200	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;
201	terminate &{+shift};	242	terminate &{+shift};
202	}	243	}
203		244
204	sub new {	245	sub new {
205	my $class = shift;	246	my $class = shift;
206	bless {	247
207	_coro_state => (new Coro::State $_[0] && \&_newcoro, @_),	248	$class->SUPER::new (\&_new_coro, @_)
208	}, $class;
209	}	249	}
210		250
211	=item $process->ready	251	=item $process->ready
212		252
213	Put the current process into the ready queue.	253	Put the given process into the ready queue.
214		254
215	=cut	255	=cut
216		256
217	sub ready {	257	=item $process->cancel (arg...)
218	push @ready, $_[0];	258
		259	Terminates the given process and makes it return the given arguments as
		260	status (default: the empty list).
		261
		262	=cut
		263
		264	sub cancel {
		265	my $self = shift;
		266	$self->{status} = [@_];
		267	push @destroy, $self;
		268	$manager->ready;
		269	&schedule if $current == $self;
		270	}
		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
		289	=item $oldprio = $process->prio ($newprio)
		290
		291	Sets (or gets, if the argument is missing) the priority of the
		292	process. Higher priority processes get run before lower priority
		293	processes. Priorities are small signed integers (currently -4 .. +3),
		294	that you can refer to using PRIO_xxx constants (use the import tag :prio
		295	to get then):
		296
		297	PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
		298	3 > 1 > 0 > -1 > -3 > -4
		299
		300	# set priority to HIGH
		301	current->prio(PRIO_HIGH);
		302
		303	The idle coroutine ($Coro::idle) always has a lower priority than any
		304	existing coroutine.
		305
		306	Changing the priority of the current process will take effect immediately,
		307	but changing the priority of processes in the ready queue (but not
		308	running) will only take effect after the next schedule (of that
		309	process). This is a bug that will be fixed in some future version.
		310
		311	=item $newprio = $process->nice ($change)
		312
		313	Similar to C<prio>, but subtract the given value from the priority (i.e.
		314	higher values mean lower priority, just as in unix).
		315
		316	=item $olddesc = $process->desc ($newdesc)
		317
		318	Sets (or gets in case the argument is missing) the description for this
		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;
219	}	327	}
220		328
221	=back	329	=back
222		330
223	=cut	331	=cut
224		332
225	1;	333	1;
226		334
227	=head1 BUGS/LIMITATIONS	335	=head1 BUGS/LIMITATIONS
228		336
229	- could be faster, especially when the core would introduce special	337	- you must make very sure that no coro is still active on global
230	support for coroutines (like it does for threads).	338	destruction. very bad things might happen otherwise (usually segfaults).
231	- there is still a memleak on coroutine termination that I could not	339
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	340	- 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	341	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).	342	to allow per-thread schedulers, but Coro::State does not yet allow
		343	this).
240		344
241	=head1 SEE ALSO	345	=head1 SEE ALSO
242		346
243	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>.
244	L<Coro::Signal>, L<Coro::State>, L<Coro::Event>.	348
		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>
245		354
246	=head1 AUTHOR	355	=head1 AUTHOR
247		356
248	Marc Lehmann <pcg@goof.com>	357	Marc Lehmann <schmorp@schmorp.de>
249	http://www.goof.com/pcg/marc/	358	http://home.schmorp.de/
250		359
251	=cut	360	=cut
252		361

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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 1.85 by root, Sat Nov 25 00:56:35 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 1.85 by root, Sat Nov 25 00:56:35 2006 UTC