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

Comparing Coro/Coro.pm (file contents):
Revision 1.21 by root, Sun Jul 22 03:24:10 2001 UTC vs.
Revision 1.80 by root, Mon Nov 6 19:56:26 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
33	WARNING: When using this module, make sure that, at program end, no
34	coroutines are still running OR just call exit before falling off the
35	end. The reason for this is that some coroutine of yours might have called
36	into a C function, and falling off the end of main:: results in returning
37	to that C function instead if to the main C interpreter.
38		30
39	=cut	31	=cut
40		32
41	package Coro;	33	package Coro;
42		34
		35	use strict;
		36	no warnings "uninitialized";
		37
43	use Coro::State;	38	use Coro::State;
44		39
45	use base Exporter;	40	use base Exporter::;
46		41
47	$VERSION = 0.10;	42	our $idle; # idle coroutine
		43	our $main; # main coroutine
		44	our $current; # current coroutine
48		45
		46	our $VERSION = '2.5';
		47
49	@EXPORT = qw(async yield schedule terminate current);	48	our @EXPORT = qw(async cede schedule terminate current);
50	@EXPORT_OK = qw($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}};
51		53
52	{	54	{
53	my @async;	55	my @async;
		56	my $init;
54		57
55	# this way of handling attributes simply is NOT scalable ;()	58	# this way of handling attributes simply is NOT scalable ;()
56	sub import {	59	sub import {
		60	no strict 'refs';
		61
57	Coro->export_to_level(1, @_);	62	Coro->export_to_level(1, @_);
		63
58	my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};	64	my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
59	*{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub {	65	*{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub {
60	my ($package, $ref) = (shift, shift);	66	my ($package, $ref) = (shift, shift);
61	my @attrs;	67	my @attrs;
62	for (@_) {	68	for (@_) {
63	if ($_ eq "Coro") {	69	if ($_ eq "Coro") {
64	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	}
65	} else {	78	} else {
66	push @attrs, $_;	79	push @attrs, $_;
67	}	80	}
68	}	81	}
69	return $old ? $old->($package, $ref, @attrs) : @attrs;	82	return $old ? $old->($package, $ref, @attrs) : @attrs;
70	};	83	};
71	}	84	}
72		85
73	sub INIT {
74	&async(pop @async) while @async;
75	}
76	}	86	}
		87
		88	=over 4
77		89
78	=item $main	90	=item $main
79		91
80	This coroutine represents the main program.	92	This coroutine represents the main program.
81		93
82	=cut	94	=cut
83		95
84	our $main = new Coro;	96	$main = new Coro;
85		97
86	=item $current (or as function: current)	98	=item $current (or as function: current)
87		99
88	The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).	100	The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
89		101
…		…
92	# maybe some other module used Coro::Specific before...	104	# maybe some other module used Coro::Specific before...
93	if ($current) {	105	if ($current) {
94	$main->{specific} = $current->{specific};	106	$main->{specific} = $current->{specific};
95	}	107	}
96		108
97	our $current = $main;	109	$current = $main;
98		110
99	sub current() { $current }	111	sub current() { $current }
100		112
101	=item $idle	113	=item $idle
102		114
…		…
104	implementation prints "FATAL: deadlock detected" and exits.	116	implementation prints "FATAL: deadlock detected" and exits.
105		117
106	=cut	118	=cut
107		119
108	# should be done using priorities :(	120	# should be done using priorities :(
109	our $idle = new Coro sub {	121	$idle = new Coro sub {
110	print STDERR "FATAL: deadlock detected\n";	122	print STDERR "FATAL: deadlock detected\n";
111	exit(51);	123	exit(51);
112	};	124	};
113		125
114	# we really need priorities...	126	# this coroutine is necessary because a coroutine
115	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	};
116		151
117	# static methods. not really.	152	# static methods. not really.
		153
		154	=back
118		155
119	=head2 STATIC METHODS	156	=head2 STATIC METHODS
120		157
121	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.
122		159
…		…
125	=item async { ... } [@args...]	162	=item async { ... } [@args...]
126		163
127	Create a new asynchronous process and return it's process object	164	Create a new asynchronous process and return it's process object
128	(usually unused). When the sub returns the new process is automatically	165	(usually unused). When the sub returns the new process is automatically
129	terminated.	166	terminated.
		167
		168	When the coroutine dies, the program will exit, just as in the main
		169	program.
130		170
131	# create a new coroutine that just prints its arguments	171	# create a new coroutine that just prints its arguments
132	async {	172	async {
133	print "@_\n";	173	print "@_\n";
134	} 1,2,3,4;	174	} 1,2,3,4;
135		175
136	The coderef you submit MUST NOT be a closure that refers to variables
137	in an outer scope. This does NOT work. Pass arguments into it instead.
138
139	=cut	176	=cut
140		177
141	sub async(&@) {	178	sub async(&@) {
142	my $pid = new Coro @_;	179	my $pid = new Coro @_;
		180	$manager->ready; # this ensures that the stack is cloned from the manager
143	$pid->ready;	181	$pid->ready;
144	$pid;	182	$pid;
145	}	183	}
146		184
147	=item schedule	185	=item schedule
…		…
150	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
151	never be called again.	189	never be called again.
152		190
153	=cut	191	=cut
154		192
155	my $prev;
156
157	sub schedule {
158	# should be done using priorities :(
159	($prev, $current) = ($current, shift @ready \|\| $idle);
160	Coro::State::transfer($prev, $current);
161	}
162
163	=item yield	193	=item cede
164		194
165	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
166	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.
167		198
168	=cut	199	=cut
169		200
170	sub yield {
171	$current->ready;
172	&schedule;
173	}
174
175	=item terminate	201	=item terminate [arg...]
176		202
177	Terminates the current process.	203	Terminates the current process with the given status values (see L<cancel>).
178
179	Future versions of this function will allow result arguments.
180		204
181	=cut	205	=cut
182		206
183	sub terminate {	207	sub terminate {
184	$current->{_results} = [@_];	208	$current->cancel (@_);
185	delete $current->{_coro_state};
186	&schedule;
187	}	209	}
188		210
189	=back	211	=back
190		212
191	# dynamic methods	213	# dynamic methods
…		…
197	=over 4	219	=over 4
198		220
199	=item new Coro \&sub [, @args...]	221	=item new Coro \&sub [, @args...]
200		222
201	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
202	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
203	the ready queue by calling the ready method.	226	by calling the ready method.
204
205	The coderef you submit MUST NOT be a closure that refers to variables
206	in an outer scope. This does NOT work. Pass arguments into it instead.
207		227
208	=cut	228	=cut
209		229
210	sub _newcoro {	230	sub _newcoro {
211	terminate &{+shift};	231	terminate &{+shift};
…		…
218	}, $class;	238	}, $class;
219	}	239	}
220		240
221	=item $process->ready	241	=item $process->ready
222		242
223	Put the current process into the ready queue.	243	Put the given process into the ready queue.
224		244
225	=cut	245	=cut
226		246
227	sub ready {	247	=item $process->cancel (arg...)
228	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;
229	}	331	}
230		332
231	=back	333	=back
232		334
233	=cut	335	=cut
234		336
235	1;	337	1;
236		338
237	=head1 BUGS/LIMITATIONS	339	=head1 BUGS/LIMITATIONS
238		340
239	- could be faster, especially when the core would introduce special	341	- you must make very sure that no coro is still active on global
240	support for coroutines (like it does for threads).	342	destruction. very bad things might happen otherwise (usually segfaults).
241	- there is still a memleak on coroutine termination that I could not	343
242	identify. Could be as small as a single SV.
243	- this module is not well-tested.
244	- if variables or arguments "disappear" (become undef) or become
245	corrupted please contact the author so he cen iron out the
246	remaining bugs.
247	- 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
248	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
249	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).
250		348
251	=head1 SEE ALSO	349	=head1 SEE ALSO
252		350
253	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>.
254	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>
255		358
256	=head1 AUTHOR	359	=head1 AUTHOR
257		360
258	Marc Lehmann <pcg@goof.com>	361	Marc Lehmann <schmorp@schmorp.de>
259	http://www.goof.com/pcg/marc/	362	http://home.schmorp.de/
260		363
261	=cut	364	=cut
262		365

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Comparing Coro/Coro.pm (file contents): Revision 1.21 by root, Sun Jul 22 03:24:10 2001 UTC vs. Revision 1.80 by root, Mon Nov 6 19:56:26 2006 UTC

Diff Legend

Comparing Coro/Coro.pm (file contents):
Revision 1.21 by root, Sun Jul 22 03:24:10 2001 UTC vs.
Revision 1.80 by root, Mon Nov 6 19:56:26 2006 UTC