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

Comparing Coro/Coro.pm (file contents):
Revision 1.30 by root, Sat Aug 11 19:59:19 2001 UTC vs.
Revision 1.85 by root, Sat Nov 25 00:56:35 2006 UTC

…		…
19	cede;	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 + C stack), that is, a coroutine has it's own	27	+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
30	callchain, it's own set of lexicals and it's own set of perl's most	28	callchain, it's own set of lexicals and it's own set of perl's most
31	important global 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
		42	our $idle; # idle handler
		43	our $main; # main coroutine
		44	our $current; # current coroutine
		45
41	$VERSION = 0.45;	46	our $VERSION = '2.5';
42		47
43	@EXPORT = qw(async cede schedule terminate current);	48	our @EXPORT = qw(async cede schedule terminate current);
44	@EXPORT_OK = qw($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;
48	my $init;	56	my $init;
49		57
50	# this way of handling attributes simply is NOT scalable ;()	58	# this way of handling attributes simply is NOT scalable ;()
51	sub import {	59	sub import {
		60	no strict 'refs';
		61
52	Coro->export_to_level(1, @_);	62	Coro->export_to_level(1, @_);
		63
53	my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};	64	my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
54	*{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub {	65	*{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub {
55	my ($package, $ref) = (shift, shift);	66	my ($package, $ref) = (shift, shift);
56	my @attrs;	67	my @attrs;
57	for (@_) {	68	for (@_) {
…		…
72	};	83	};
73	}	84	}
74		85
75	}	86	}
76		87
		88	=over 4
		89
77	=item $main	90	=item $main
78		91
79	This coroutine represents the main program.	92	This coroutine represents the main program.
80		93
81	=cut	94	=cut
82		95
83	our $main = new Coro;	96	$main = new Coro;
84		97
85	=item $current (or as function: current)	98	=item $current (or as function: current)
86		99
87	The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).	100	The current coroutine (the last coroutine switched to). The initial value
		101	is C<$main> (of course).
		102
		103	This variable is B<strictly> I<read-only>. It is provided for performance
		104	reasons. If performance is not essentiel you are encouraged to use the
		105	C<Coro::current> function instead.
88		106
89	=cut	107	=cut
90		108
91	# maybe some other module used Coro::Specific before...	109	# maybe some other module used Coro::Specific before...
92	if ($current) {	110	if ($current) {
93	$main->{specific} = $current->{specific};	111	$main->{specific} = $current->{specific};
94	}	112	}
95		113
96	our $current = $main;	114	$current = $main;
97		115
98	sub current() { $current }	116	sub current() { $current }
99		117
100	=item $idle	118	=item $idle
101		119
102	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
103	implementation prints "FATAL: deadlock detected" and exits.	121	to run. The default implementation prints "FATAL: deadlock detected" and
		122	exits.
104		123
105	=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.
106		127
107	# should be done using priorities :(	128	=cut
108	our $idle = new Coro sub {	129
		130	$idle = sub {
109	print STDERR "FATAL: deadlock detected\n";	131	print STDERR "FATAL: deadlock detected\n";
110	exit(51);	132	exit (51);
111	};	133	};
112		134
113	# this coroutine is necessary because a coroutine	135	# this coroutine is necessary because a coroutine
114	# cannot destroy itself.	136	# cannot destroy itself.
115	my @destroy;	137	my @destroy;
		138	my $manager;
116	my $manager = new Coro sub {	139	$manager = new Coro sub {
117	while() {	140	while () {
118	delete ((pop @destroy)->{_coro_state}) while @destroy;	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	}
119	&schedule;	157	&schedule;
120	}	158	}
121	};	159	};
122		160
123	# static methods. not really.	161	# static methods. not really.
124		162
		163	=back
		164
125	=head2 STATIC METHODS	165	=head2 STATIC METHODS
126		166
127	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.
128		168
129	=over 4	169	=over 4
…		…
131	=item async { ... } [@args...]	171	=item async { ... } [@args...]
132		172
133	Create a new asynchronous process and return it's process object	173	Create a new asynchronous process and return it's process object
134	(usually unused). When the sub returns the new process is automatically	174	(usually unused). When the sub returns the new process is automatically
135	terminated.	175	terminated.
		176
		177	When the coroutine dies, the program will exit, just as in the main
		178	program.
136		179
137	# create a new coroutine that just prints its arguments	180	# create a new coroutine that just prints its arguments
138	async {	181	async {
139	print "@_\n";	182	print "@_\n";
140	} 1,2,3,4;	183	} 1,2,3,4;
141		184
142	The coderef you submit MUST NOT be a closure that refers to variables
143	in an outer scope. This does NOT work. Pass arguments into it instead.
144
145	=cut	185	=cut
146		186
147	sub async(&@) {	187	sub async(&@) {
148	my $pid = new Coro @_;	188	my $pid = new Coro @_;
149	$manager->ready; # this ensures that the stack is cloned from the manager
150	$pid->ready;	189	$pid->ready;
151	$pid;	190	$pid
152	}	191	}
153		192
154	=item schedule	193	=item schedule
155		194
156	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
…		…
165	ready queue and calls C<schedule>, which has the effect of giving up the	204	ready queue and calls C<schedule>, which has the effect of giving up the
166	current "timeslice" to other coroutines of the same or higher priority.	205	current "timeslice" to other coroutines of the same or higher priority.
167		206
168	=cut	207	=cut
169		208
170	=item terminate	209	=item terminate [arg...]
171		210
172	Terminates the current process.	211	Terminates the current process with the given status values (see L<cancel>).
173
174	Future versions of this function will allow result arguments.
175		212
176	=cut	213	=cut
177		214
178	sub terminate {	215	sub terminate {
179	$current->cancel;	216	$current->cancel (@_);
180	&schedule;
181	die; # NORETURN
182	}	217	}
183		218
184	=back	219	=back
185		220
186	# dynamic methods	221	# dynamic methods
…		…
192	=over 4	227	=over 4
193		228
194	=item new Coro \&sub [, @args...]	229	=item new Coro \&sub [, @args...]
195		230
196	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
197	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
198	the ready queue by calling the ready method.	234	by calling the ready method.
199		235
200	The coderef you submit MUST NOT be a closure that refers to variables
201	in an outer scope. This does NOT work. Pass arguments into it instead.
202
203	=cut	236	=cut
204		237
205	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;
206	terminate &{+shift};	242	terminate &{+shift};
207	}	243	}
208		244
209	sub new {	245	sub new {
210	my $class = shift;	246	my $class = shift;
211	bless {	247
212	_coro_state => (new Coro::State $_[0] && \&_newcoro, @_),	248	$class->SUPER::new (\&_new_coro, @_)
213	}, $class;
214	}	249	}
215		250
216	=item $process->ready	251	=item $process->ready
217		252
218	Put the current process into the ready queue.	253	Put the given process into the ready queue.
219		254
220	=cut	255	=cut
221		256
222	=item $process->cancel	257	=item $process->cancel (arg...)
223		258
224	Like C<terminate>, but terminates the specified process instead.	259	Terminates the given process and makes it return the given arguments as
		260	status (default: the empty list).
225		261
226	=cut	262	=cut
227		263
228	sub cancel {	264	sub cancel {
		265	my $self = shift;
		266	$self->{status} = [@_];
229	push @destroy, $_[0];	267	push @destroy, $self;
230	$manager->ready;	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;
231	}	327	}
232		328
233	=back	329	=back
234		330
235	=cut	331	=cut
236		332
237	1;	333	1;
238		334
239	=head1 BUGS/LIMITATIONS	335	=head1 BUGS/LIMITATIONS
240		336
241	- could be faster, especially when the core would introduce special	337	- you must make very sure that no coro is still active on global
242	support for coroutines (like it does for threads).	338	destruction. very bad things might happen otherwise (usually segfaults).
243	- there is still a memleak on coroutine termination that I could not	339
244	identify. Could be as small as a single SV.
245	- this module is not well-tested.
246	- if variables or arguments "disappear" (become undef) or become
247	corrupted please contact the author so he cen iron out the
248	remaining bugs.
249	- 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
250	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
251	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).
252		344
253	=head1 SEE ALSO	345	=head1 SEE ALSO
254		346
255	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>.
256	L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,	348
257	L<Coro::Handle>, L<Coro::Socket>.	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>
258		354
259	=head1 AUTHOR	355	=head1 AUTHOR
260		356
261	Marc Lehmann <pcg@goof.com>	357	Marc Lehmann <schmorp@schmorp.de>
262	http://www.goof.com/pcg/marc/	358	http://home.schmorp.de/
263		359
264	=cut	360	=cut
265		361

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Comparing Coro/Coro.pm (file contents): Revision 1.30 by root, Sat Aug 11 19:59:19 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 1.30 by root, Sat Aug 11 19:59:19 2001 UTC vs.
Revision 1.85 by root, Sat Nov 25 00:56:35 2006 UTC