[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 1.85 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
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 qw(Coro::State Exporter);
40		41
41	$VERSION = 0.10;	42	our $idle; # idle handler
		43	our $main; # main coroutine
		44	our $current; # current coroutine
42		45
		46	our $VERSION = '2.5';
		47
43	@EXPORT = qw(async yield schedule terminate current);	48	our @EXPORT = qw(async cede schedule terminate current);
44	@EXPORT_OK = qw($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
		101	is C<$main> (of course).
		102
		103	This variable is B<strictly> I<read-only>. It is provided for performance
		104	reasons. If performance is not essentiel you are encouraged to use the
		105	C<Coro::current> function instead.
83		106
84	=cut	107	=cut
85		108
86	# maybe some other module used Coro::Specific before...	109	# maybe some other module used Coro::Specific before...
87	if ($current) {	110	if ($current) {
88	$main->{specific} = $current->{specific};	111	$main->{specific} = $current->{specific};
89	}	112	}
90		113
91	our $current = $main;	114	$current = $main;
92		115
93	sub current() { $current }	116	sub current() { $current }
94		117
95	=item $idle	118	=item $idle
96		119
97	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
98	implementation prints "FATAL: deadlock detected" and exits.	121	to run. The default implementation prints "FATAL: deadlock detected" and
		122	exits.
99		123
100	=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.
101		127
102	# should be done using priorities :(	128	=cut
103	our $idle = new Coro sub {	129
		130	$idle = sub {
104	print STDERR "FATAL: deadlock detected\n";	131	print STDERR "FATAL: deadlock detected\n";
105	exit(51);	132	exit (51);
106	};	133	};
107		134
108	# we really need priorities...	135	# this coroutine is necessary because a coroutine
109	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	};
110		160
111	# static methods. not really.	161	# static methods. not really.
		162
		163	=back
112		164
113	=head2 STATIC METHODS	165	=head2 STATIC METHODS
114		166
115	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.
116		168
…		…
119	=item async { ... } [@args...]	171	=item async { ... } [@args...]
120		172
121	Create a new asynchronous process and return it's process object	173	Create a new asynchronous process and return it's process object
122	(usually unused). When the sub returns the new process is automatically	174	(usually unused). When the sub returns the new process is automatically
123	terminated.	175	terminated.
		176
		177	When the coroutine dies, the program will exit, just as in the main
		178	program.
124		179
125	# create a new coroutine that just prints its arguments	180	# create a new coroutine that just prints its arguments
126	async {	181	async {
127	print "@_\n";	182	print "@_\n";
128	} 1,2,3,4;	183	} 1,2,3,4;
129		184
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	185	=cut
134		186
135	sub async(&@) {	187	sub async(&@) {
136	my $pid = new Coro @_;	188	my $pid = new Coro @_;
137	$pid->ready;	189	$pid->ready;
138	$pid;	190	$pid
139	}	191	}
140		192
141	=item schedule	193	=item schedule
142		194
143	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
144	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
145	never be called again.	197	never be called again.
146		198
147	=cut	199	=cut
148		200
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	201	=item cede
158		202
159	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
160	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.
161		206
162	=cut	207	=cut
163		208
164	sub yield {
165	$current->ready;
166	&schedule;
167	}
168
169	=item terminate	209	=item terminate [arg...]
170		210
171	Terminates the current process.	211	Terminates the current process with the given status values (see L<cancel>).
172
173	Future versions of this function will allow result arguments.
174		212
175	=cut	213	=cut
176		214
177	sub terminate {	215	sub terminate {
178	$current->{_results} = [@_];	216	$current->cancel (@_);
179	&schedule;
180	}	217	}
181		218
182	=back	219	=back
183		220
184	# dynamic methods	221	# dynamic methods
…		…
190	=over 4	227	=over 4
191		228
192	=item new Coro \&sub [, @args...]	229	=item new Coro \&sub [, @args...]
193		230
194	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
195	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
196	the ready queue by calling the ready method.	234	by calling the ready method.
197		235
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
201	=cut	236	=cut
202		237
203	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;
204	terminate &{+shift};	242	terminate &{+shift};
205	}	243	}
206		244
207	sub new {	245	sub new {
208	my $class = shift;	246	my $class = shift;
209	bless {	247
210	_coro_state => (new Coro::State $_[0] && \&_newcoro, @_),	248	$class->SUPER::new (\&_new_coro, @_)
211	}, $class;
212	}	249	}
213		250
214	=item $process->ready	251	=item $process->ready
215		252
216	Put the current process into the ready queue.	253	Put the given process into the ready queue.
217		254
218	=cut	255	=cut
219		256
220	sub ready {	257	=item $process->cancel (arg...)
221	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;
222	}	327	}
223		328
224	=back	329	=back
225		330
226	=cut	331	=cut
227		332
228	1;	333	1;
229		334
230	=head1 BUGS/LIMITATIONS	335	=head1 BUGS/LIMITATIONS
231		336
232	- could be faster, especially when the core would introduce special	337	- you must make very sure that no coro is still active on global
233	support for coroutines (like it does for threads).	338	destruction. very bad things might happen otherwise (usually segfaults).
234	- there is still a memleak on coroutine termination that I could not	339
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	340	- 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	341	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).	342	to allow per-thread schedulers, but Coro::State does not yet allow
		343	this).
243		344
244	=head1 SEE ALSO	345	=head1 SEE ALSO
245		346
246	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>.
247	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>
248		354
249	=head1 AUTHOR	355	=head1 AUTHOR
250		356
251	Marc Lehmann <pcg@goof.com>	357	Marc Lehmann <schmorp@schmorp.de>
252	http://www.goof.com/pcg/marc/	358	http://home.schmorp.de/
253		359
254	=cut	360	=cut
255		361

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