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

Comparing Coro/Coro.pm (file contents):
Revision 1.20 by root, Sat Jul 21 18:21:45 2001 UTC vs.
Revision 1.79 by root, Fri Nov 3 00:56:02 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
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), that is, a coroutine has it's own callchain, it's	27	+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
30	own set of lexicals and it's own set of perl's most important global	28	callchain, it's own set of lexicals and it's own set of perl's most
31	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 Exporter::;
40		41
		42	our $idle; # idle coroutine
		43	our $main; # main coroutine
		44	our $current; # current coroutine
		45
41	$VERSION = 0.10;	46	our $VERSION = '2.1';
42		47
43	@EXPORT = qw(async yield schedule terminate current);	48	our @EXPORT = qw(async cede schedule terminate current);
44	@EXPORT_OK = qw($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}};
45		53
46	{	54	{
47	my @async;	55	my @async;
		56	my $init;
48		57
49	# this way of handling attributes simply is NOT scalable ;()	58	# this way of handling attributes simply is NOT scalable ;()
50	sub import {	59	sub import {
		60	no strict 'refs';
		61
51	Coro->export_to_level(1, @_);	62	Coro->export_to_level(1, @_);
		63
52	my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};	64	my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
53	*{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub {	65	*{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub {
54	my ($package, $ref) = (shift, shift);	66	my ($package, $ref) = (shift, shift);
55	my @attrs;	67	my @attrs;
56	for (@_) {	68	for (@_) {
57	if ($_ eq "Coro") {	69	if ($_ eq "Coro") {
58	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	}
59	} else {	78	} else {
60	push @attrs, $_;	79	push @attrs, $_;
61	}	80	}
62	}	81	}
63	return $old ? $old->($package, $ref, @attrs) : @attrs;	82	return $old ? $old->($package, $ref, @attrs) : @attrs;
64	};	83	};
65	}	84	}
66		85
67	sub INIT {
68	&async(pop @async) while @async;
69	}
70	}	86	}
		87
		88	=over 4
71		89
72	=item $main	90	=item $main
73		91
74	This coroutine represents the main program.	92	This coroutine represents the main program.
75		93
76	=cut	94	=cut
77		95
78	our $main = new Coro;	96	$main = new Coro;
79		97
80	=item $current (or as function: current)	98	=item $current (or as function: current)
81		99
82	The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).	100	The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
83		101
…		…
86	# maybe some other module used Coro::Specific before...	104	# maybe some other module used Coro::Specific before...
87	if ($current) {	105	if ($current) {
88	$main->{specific} = $current->{specific};	106	$main->{specific} = $current->{specific};
89	}	107	}
90		108
91	our $current = $main;	109	$current = $main;
92		110
93	sub current() { $current }	111	sub current() { $current }
94		112
95	=item $idle	113	=item $idle
96		114
…		…
98	implementation prints "FATAL: deadlock detected" and exits.	116	implementation prints "FATAL: deadlock detected" and exits.
99		117
100	=cut	118	=cut
101		119
102	# should be done using priorities :(	120	# should be done using priorities :(
103	our $idle = new Coro sub {	121	$idle = new Coro sub {
104	print STDERR "FATAL: deadlock detected\n";	122	print STDERR "FATAL: deadlock detected\n";
105	exit(51);	123	exit(51);
106	};	124	};
107		125
108	# we really need priorities...	126	# this coroutine is necessary because a coroutine
109	my @ready; # the ready queue. hehe, rather broken ;)	127	# cannot destroy itself.
		128	my @destroy;
		129	my $manager;
		130	$manager = new Coro sub {
		131	while () {
		132	# by overwriting the state object with the manager we destroy it
		133	# while still being able to schedule this coroutine (in case it has
		134	# been readied multiple times. this is harmless since the manager
		135	# can be called as many times as neccessary and will always
		136	# remove itself from the runqueue
		137	while (@destroy) {
		138	my $coro = pop @destroy;
		139	$coro->{status} \|\|= [];
		140	$_->ready for @{delete $coro->{join} \|\| []};
		141
		142	# the next line destroys the _coro_state, but keeps the
		143	# process itself intact (we basically make it a zombie
		144	# process that always runs the manager thread, so it's possible
		145	# to transfer() to this process).
		146	$coro->{_coro_state} = $manager->{_coro_state};
		147	}
		148	&schedule;
		149	}
		150	};
110		151
111	# static methods. not really.	152	# static methods. not really.
		153
		154	=back
112		155
113	=head2 STATIC METHODS	156	=head2 STATIC METHODS
114		157
115	Static methods are actually functions that operate on the current process only.	158	Static methods are actually functions that operate on the current process only.
116		159
…		…
119	=item async { ... } [@args...]	162	=item async { ... } [@args...]
120		163
121	Create a new asynchronous process and return it's process object	164	Create a new asynchronous process and return it's process object
122	(usually unused). When the sub returns the new process is automatically	165	(usually unused). When the sub returns the new process is automatically
123	terminated.	166	terminated.
		167
		168	When the coroutine dies, the program will exit, just as in the main
		169	program.
124		170
125	# create a new coroutine that just prints its arguments	171	# create a new coroutine that just prints its arguments
126	async {	172	async {
127	print "@_\n";	173	print "@_\n";
128	} 1,2,3,4;	174	} 1,2,3,4;
129		175
130	The coderef you submit MUST NOT be a closure that refers to variables
131	in an outer scope. This does NOT work. Pass arguments into it instead.
132
133	=cut	176	=cut
134		177
135	sub async(&@) {	178	sub async(&@) {
136	my $pid = new Coro @_;	179	my $pid = new Coro @_;
		180	$manager->ready; # this ensures that the stack is cloned from the manager
137	$pid->ready;	181	$pid->ready;
138	$pid;	182	$pid;
139	}	183	}
140		184
141	=item schedule	185	=item schedule
…		…
144	into the ready queue, so calling this function usually means you will	188	into the ready queue, so calling this function usually means you will
145	never be called again.	189	never be called again.
146		190
147	=cut	191	=cut
148		192
149	my $prev;
150
151	sub schedule {
152	# should be done using priorities :(
153	($prev, $current) = ($current, shift @ready \|\| $idle);
154	Coro::State::transfer($prev, $current);
155	}
156
157	=item yield	193	=item cede
158		194
159	Yield to other processes. This function puts the current process into the	195	"Cede" to other processes. This function puts the current process into the
160	ready queue and calls C<schedule>.	196	ready queue and calls C<schedule>, which has the effect of giving up the
		197	current "timeslice" to other coroutines of the same or higher priority.
161		198
162	=cut	199	=cut
163		200
164	sub yield {
165	$current->ready;
166	&schedule;
167	}
168
169	=item terminate	201	=item terminate [arg...]
170		202
171	Terminates the current process.	203	Terminates the current process with the given status values (see L<cancel>).
172
173	Future versions of this function will allow result arguments.
174		204
175	=cut	205	=cut
176		206
177	sub terminate {	207	sub terminate {
178	$current->{_results} = [@_];	208	$current->cancel (@_);
179	&schedule;
180	}	209	}
181		210
182	=back	211	=back
183		212
184	# dynamic methods	213	# dynamic methods
…		…
190	=over 4	219	=over 4
191		220
192	=item new Coro \&sub [, @args...]	221	=item new Coro \&sub [, @args...]
193		222
194	Create a new process and return it. When the sub returns the process	223	Create a new process and return it. When the sub returns the process
195	automatically terminates. To start the process you must first put it into	224	automatically terminates as if C<terminate> with the returned values were
		225	called. To make the process run you must first put it into the ready queue
196	the ready queue by calling the ready method.	226	by calling the ready method.
197
198	The coderef you submit MUST NOT be a closure that refers to variables
199	in an outer scope. This does NOT work. Pass arguments into it instead.
200		227
201	=cut	228	=cut
202		229
203	sub _newcoro {	230	sub _newcoro {
204	terminate &{+shift};	231	terminate &{+shift};
…		…
211	}, $class;	238	}, $class;
212	}	239	}
213		240
214	=item $process->ready	241	=item $process->ready
215		242
216	Put the current process into the ready queue.	243	Put the given process into the ready queue.
217		244
218	=cut	245	=cut
219		246
220	sub ready {	247	=item $process->cancel (arg...)
221	push @ready, $_[0];	248
		249	Terminates the given process and makes it return the given arguments as
		250	status (default: the empty list).
		251
		252	=cut
		253
		254	sub cancel {
		255	my $self = shift;
		256	$self->{status} = [@_];
		257	push @destroy, $self;
		258	$manager->ready;
		259	&schedule if $current == $self;
		260	}
		261
		262	=item $process->join
		263
		264	Wait until the coroutine terminates and return any values given to the
		265	C<terminate> or C<cancel> functions. C<join> can be called multiple times
		266	from multiple processes.
		267
		268	=cut
		269
		270	sub join {
		271	my $self = shift;
		272	unless ($self->{status}) {
		273	push @{$self->{join}}, $current;
		274	&schedule;
		275	}
		276	wantarray ? @{$self->{status}} : $self->{status}[0];
		277	}
		278
		279	=item $oldprio = $process->prio($newprio)
		280
		281	Sets (or gets, if the argument is missing) the priority of the
		282	process. Higher priority processes get run before lower priority
		283	processes. Priorities are small signed integers (currently -4 .. +3),
		284	that you can refer to using PRIO_xxx constants (use the import tag :prio
		285	to get then):
		286
		287	PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
		288	3 > 1 > 0 > -1 > -3 > -4
		289
		290	# set priority to HIGH
		291	current->prio(PRIO_HIGH);
		292
		293	The idle coroutine ($Coro::idle) always has a lower priority than any
		294	existing coroutine.
		295
		296	Changing the priority of the current process will take effect immediately,
		297	but changing the priority of processes in the ready queue (but not
		298	running) will only take effect after the next schedule (of that
		299	process). This is a bug that will be fixed in some future version.
		300
		301	=cut
		302
		303	sub prio {
		304	my $old = $_[0]{prio};
		305	$_[0]{prio} = $_[1] if @_ > 1;
		306	$old;
		307	}
		308
		309	=item $newprio = $process->nice($change)
		310
		311	Similar to C<prio>, but subtract the given value from the priority (i.e.
		312	higher values mean lower priority, just as in unix).
		313
		314	=cut
		315
		316	sub nice {
		317	$_[0]{prio} -= $_[1];
		318	}
		319
		320	=item $olddesc = $process->desc($newdesc)
		321
		322	Sets (or gets in case the argument is missing) the description for this
		323	process. This is just a free-form string you can associate with a process.
		324
		325	=cut
		326
		327	sub desc {
		328	my $old = $_[0]{desc};
		329	$_[0]{desc} = $_[1] if @_ > 1;
		330	$old;
222	}	331	}
223		332
224	=back	333	=back
225		334
226	=cut	335	=cut
227		336
228	1;	337	1;
229		338
230	=head1 BUGS/LIMITATIONS	339	=head1 BUGS/LIMITATIONS
231		340
232	- could be faster, especially when the core would introduce special	341	- you must make very sure that no coro is still active on global
233	support for coroutines (like it does for threads).	342	destruction. very bad things might happen otherwise (usually segfaults).
234	- there is still a memleak on coroutine termination that I could not	343
235	identify. Could be as small as a single SV.
236	- this module is not well-tested.
237	- if variables or arguments "disappear" (become undef) or become
238	corrupted please contact the author so he cen iron out the
239	remaining bugs.
240	- this module is not thread-safe. You must only ever use this module from	344	- this module is not thread-safe. You should only ever use this module
241	the same thread (this requirement might be loosened in the future to	345	from the same thread (this requirement might be losened in the future
242	allow per-thread schedulers, but Coro::State does not yet allow this).	346	to allow per-thread schedulers, but Coro::State does not yet allow
		347	this).
243		348
244	=head1 SEE ALSO	349	=head1 SEE ALSO
245		350
246	L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,	351	Support/Utility: L<Coro::Cont>, L<Coro::Specific>, L<Coro::State>, L<Coro::Util>.
247	L<Coro::Signal>, L<Coro::State>, L<Coro::Event>.	352
		353	Locking/IPC: L<Coro::Signal>, L<Coro::Channel>, L<Coro::Semaphore>, L<Coro::SemaphoreSet>, L<Coro::RWLock>.
		354
		355	Event/IO: L<Coro::Timer>, L<Coro::Event>, L<Coro::Handle>, L<Coro::Socket>, L<Coro::Select>.
		356
		357	Embedding: L<Coro:MakeMaker>
248		358
249	=head1 AUTHOR	359	=head1 AUTHOR
250		360
251	Marc Lehmann <pcg@goof.com>	361	Marc Lehmann <schmorp@schmorp.de>
252	http://www.goof.com/pcg/marc/	362	http://home.schmorp.de/
253		363
254	=cut	364	=cut
255		365

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Comparing Coro/Coro.pm (file contents): Revision 1.20 by root, Sat Jul 21 18:21:45 2001 UTC vs. Revision 1.79 by root, Fri Nov 3 00:56:02 2006 UTC

Diff Legend

Comparing Coro/Coro.pm (file contents):
Revision 1.20 by root, Sat Jul 21 18:21:45 2001 UTC vs.
Revision 1.79 by root, Fri Nov 3 00:56:02 2006 UTC