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

Comparing Coro/Coro.pm (file contents):
Revision 1.8 by root, Sat Jul 14 22:14:21 2001 UTC vs.
Revision 1.86 by root, Sat Nov 25 01:14:11 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
		24	threads but don't run in parallel.
		25
		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.
		30
23	=cut	31	=cut
24		32
25	package Coro;	33	package Coro;
26		34
		35	use strict;
		36	no warnings "uninitialized";
		37
27	use Coro::State;	38	use Coro::State;
28		39
29	use base Exporter;	40	use base qw(Coro::State Exporter);
30		41
31	$VERSION = 0.03;	42	our $idle; # idle handler
		43	our $main; # main coroutine
		44	our $current; # current coroutine
32		45
33	@EXPORT = qw(async yield schedule);	46	our $VERSION = '2.5';
34	@EXPORT_OK = qw($current);	47
		48	our @EXPORT = qw(async cede schedule terminate 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}};
35		53
36	{	54	{
37	use subs 'async';
38
39	my @async;	55	my @async;
		56	my $init;
40		57
41	# this way of handling attributes simply is NOT scalable ;()	58	# this way of handling attributes simply is NOT scalable ;()
42	sub import {	59	sub import {
		60	no strict 'refs';
		61
43	Coro->export_to_level(1, @_);	62	Coro->export_to_level(1, @_);
		63
44	my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};	64	my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
45	*{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub {	65	*{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub {
46	my ($package, $ref) = (shift, shift);	66	my ($package, $ref) = (shift, shift);
47	my @attrs;	67	my @attrs;
48	for (@_) {	68	for (@_) {
49	if ($_ eq "Coro") {	69	if ($_ eq "Coro") {
50	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	}
51	} else {	78	} else {
52	push @attrs, @_;	79	push @attrs, $_;
53	}	80	}
54	}	81	}
55	return $old ? $old->($package, $name, @attrs) : @attrs;	82	return $old ? $old->($package, $ref, @attrs) : @attrs;
56	};	83	};
57	}	84	}
58		85
59	sub INIT {
60	async pop @async while @async;
61	}
62	}	86	}
63		87
64	my $idle = new Coro sub {	88	=over 4
65	&yield while 1;
66	};
67		89
68	=item $main	90	=item $main
69		91
70	This coroutine represents the main program.	92	This coroutine represents the main program.
71		93
72	=cut	94	=cut
73		95
74	$main = new Coro;	96	$main = new Coro;
75		97
76	=item $current	98	=item $current (or as function: current)
77		99
78	The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).	100	The current coroutine (the last coroutine switched to). The initial value
		101	is C<$main> (of course).
		102
		103	This variable is B<strictly> I<read-only>. It is provided for performance
		104	reasons. If performance is not essentiel you are encouraged to use the
		105	C<Coro::current> function instead.
79		106
80	=cut	107	=cut
81		108
82	# maybe some other module used Coro::Specific before...	109	# maybe some other module used Coro::Specific before...
83	if ($current) {	110	if ($current) {
84	$main->{specific} = $current->{specific};	111	$main->{specific} = $current->{specific};
85	}	112	}
86		113
87	$current = $main;	114	$current = $main;
88		115
89	# we really need priorities...	116	sub current() { $current }
90	my @ready = (); # the ready queue. hehe, rather broken ;)	117
		118	=item $idle
		119
		120	A callback that is called whenever the scheduler finds no ready coroutines
		121	to run. The default implementation prints "FATAL: deadlock detected" and
		122	exits.
		123
		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.
		127
		128	=cut
		129
		130	$idle = sub {
		131	print STDERR "FATAL: deadlock detected\n";
		132	exit (51);
		133	};
		134
		135	# this coroutine is necessary because a coroutine
		136	# cannot destroy itself.
		137	my @destroy;
		138	my $manager; $manager = new Coro sub {
		139	while () {
		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	}
		156	&schedule;
		157	}
		158	};
91		159
92	# static methods. not really.	160	# static methods. not really.
93		161
		162	=back
		163
94	=head2 STATIC METHODS	164	=head2 STATIC METHODS
95		165
96	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.
97		167
98	=over 4	168	=over 4
99		169
100	=item async { ... };	170	=item async { ... } [@args...]
101		171
102	Create a new asynchronous process and return it's process object	172	Create a new asynchronous process and return it's process object
103	(usually unused). When the sub returns the new process is automatically	173	(usually unused). When the sub returns the new process is automatically
104	terminated.	174	terminated.
105		175
106	=cut	176	When the coroutine dies, the program will exit, just as in the main
		177	program.
107		178
		179	# create a new coroutine that just prints its arguments
		180	async {
		181	print "@_\n";
		182	} 1,2,3,4;
		183
		184	=cut
		185
108	sub async(&) {	186	sub async(&@) {
109	(new Coro $_[0])->ready;	187	my $pid = new Coro @_;
		188	$pid->ready;
		189	$pid
110	}	190	}
111		191
112	=item schedule	192	=item schedule
113		193
114	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
115	into the ready queue, so calling this function usually means you will	195	into the ready queue, so calling this function usually means you will
116	never be called again.	196	never be called again.
117		197
118	=cut	198	=cut
119		199
120	my $prev;
121
122	sub schedule {
123	($prev, $current) = ($current, shift @ready);
124	Coro::State::transfer($prev, $current);
125	}
126
127	=item yield	200	=item cede
128		201
129	Yield to other processes. This function puts the current process into the	202	"Cede" to other processes. This function puts the current process into the
130	ready queue and calls C<schedule>.	203	ready queue and calls C<schedule>, which has the effect of giving up the
		204	current "timeslice" to other coroutines of the same or higher priority.
131		205
132	=cut	206	=cut
133		207
134	sub yield {
135	$current->ready;
136	&schedule;
137	}
138
139	=item terminate	208	=item terminate [arg...]
140		209
141	Terminates the current process.	210	Terminates the current process with the given status values (see L<cancel>).
142		211
143	=cut	212	=cut
144		213
145	sub terminate {	214	sub terminate {
146	&schedule;	215	$current->cancel (@_);
147	}	216	}
148		217
149	=back	218	=back
150		219
151	# dynamic methods	220	# dynamic methods
…		…
154		223
155	These are the methods you can call on process objects.	224	These are the methods you can call on process objects.
156		225
157	=over 4	226	=over 4
158		227
159	=item new Coro \⊂	228	=item new Coro \&sub [, @args...]
160		229
161	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
162	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
163	the ready queue by calling the ready method.	233	by calling the ready method.
164		234
165	=cut	235	=cut
		236
		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;
		241	terminate &{+shift};
		242	}
166		243
167	sub new {	244	sub new {
168	my $class = shift;	245	my $class = shift;
169	my $proc = $_[0];	246
170	bless {	247	$class->SUPER::new (\&_new_coro, @_)
171	_coro_state => new Coro::State ($proc ? sub { &$proc; &terminate } : $proc),
172	}, $class;
173	}	248	}
174		249
175	=item $process->ready	250	=item $process->ready
176		251
177	Put the current process into the ready queue.	252	Put the given process into the ready queue.
178		253
179	=cut	254	=cut
180		255
181	sub ready {	256	=item $process->cancel (arg...)
182	push @ready, $_[0];	257
		258	Terminates the given process and makes it return the given arguments as
		259	status (default: the empty list).
		260
		261	=cut
		262
		263	sub cancel {
		264	my $self = shift;
		265	$self->{status} = [@_];
		266	push @destroy, $self;
		267	$manager->ready;
		268	&schedule if $current == $self;
		269	}
		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
		288	=item $oldprio = $process->prio ($newprio)
		289
		290	Sets (or gets, if the argument is missing) the priority of the
		291	process. Higher priority processes get run before lower priority
		292	processes. Priorities are small signed integers (currently -4 .. +3),
		293	that you can refer to using PRIO_xxx constants (use the import tag :prio
		294	to get then):
		295
		296	PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
		297	3 > 1 > 0 > -1 > -3 > -4
		298
		299	# set priority to HIGH
		300	current->prio(PRIO_HIGH);
		301
		302	The idle coroutine ($Coro::idle) always has a lower priority than any
		303	existing coroutine.
		304
		305	Changing the priority of the current process will take effect immediately,
		306	but changing the priority of processes in the ready queue (but not
		307	running) will only take effect after the next schedule (of that
		308	process). This is a bug that will be fixed in some future version.
		309
		310	=item $newprio = $process->nice ($change)
		311
		312	Similar to C<prio>, but subtract the given value from the priority (i.e.
		313	higher values mean lower priority, just as in unix).
		314
		315	=item $olddesc = $process->desc ($newdesc)
		316
		317	Sets (or gets in case the argument is missing) the description for this
		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;
183	}	326	}
184		327
185	=back	328	=back
186		329
187	=cut	330	=cut
188		331
189	1;	332	1;
190		333
		334	=head1 BUGS/LIMITATIONS
		335
		336	- you must make very sure that no coro is still active on global
		337	destruction. very bad things might happen otherwise (usually segfaults).
		338
		339	- this module is not thread-safe. You should only ever use this module
		340	from the same thread (this requirement might be losened in the future
		341	to allow per-thread schedulers, but Coro::State does not yet allow
		342	this).
		343
		344	=head1 SEE ALSO
		345
		346	Support/Utility: L<Coro::Cont>, L<Coro::Specific>, L<Coro::State>, L<Coro::Util>.
		347
		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>
		353
191	=head1 AUTHOR	354	=head1 AUTHOR
192		355
193	Marc Lehmann <pcg@goof.com>	356	Marc Lehmann <schmorp@schmorp.de>
194	http://www.goof.com/pcg/marc/	357	http://home.schmorp.de/
195		358
196	=cut	359	=cut
197		360

Diff Legend

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

Comparing Coro/Coro.pm (file contents): Revision 1.8 by root, Sat Jul 14 22:14:21 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 1.8 by root, Sat Jul 14 22:14:21 2001 UTC vs.
Revision 1.86 by root, Sat Nov 25 01:14:11 2006 UTC