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Comparing cvsroot/Coro/Coro.pm (file contents):
Revision 1.196 by root, Sat Aug 30 03:07:46 2008 UTC vs.
Revision 1.219 by root, Sun Nov 16 00:55:41 2008 UTC

16 cede; # yield to coroutine 16 cede; # yield to coroutine
17 print "3\n"; 17 print "3\n";
18 cede; # and again 18 cede; # and again
19 19
20 # use locking 20 # use locking
21 use Coro::Semaphore;
21 my $lock = new Coro::Semaphore; 22 my $lock = new Coro::Semaphore;
22 my $locked; 23 my $locked;
23 24
24 $lock->down; 25 $lock->down;
25 $locked = 1; 26 $locked = 1;
55 56
56=cut 57=cut
57 58
58package Coro; 59package Coro;
59 60
60use strict; 61use strict qw(vars subs);
61no warnings "uninitialized"; 62no warnings "uninitialized";
62 63
63use Coro::State; 64use Coro::State;
64 65
65use base qw(Coro::State Exporter); 66use base qw(Coro::State Exporter);
66 67
67our $idle; # idle handler 68our $idle; # idle handler
68our $main; # main coroutine 69our $main; # main coroutine
69our $current; # current coroutine 70our $current; # current coroutine
70 71
71our $VERSION = 4.745; 72our $VERSION = 5.0;
72 73
73our @EXPORT = qw(async async_pool cede schedule terminate current unblock_sub); 74our @EXPORT = qw(async async_pool cede schedule terminate current unblock_sub);
74our %EXPORT_TAGS = ( 75our %EXPORT_TAGS = (
75 prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)], 76 prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],
76); 77);
151 $self->_destroy 152 $self->_destroy
152 or return; 153 or return;
153 154
154 # call all destruction callbacks 155 # call all destruction callbacks
155 $_->(@{$self->{_status}}) 156 $_->(@{$self->{_status}})
156 for @{(delete $self->{_on_destroy}) || []}; 157 for @{ delete $self->{_on_destroy} || [] };
157} 158}
158 159
159# this coroutine is necessary because a coroutine 160# this coroutine is necessary because a coroutine
160# cannot destroy itself. 161# cannot destroy itself.
161my @destroy; 162my @destroy;
167 while @destroy; 168 while @destroy;
168 169
169 &schedule; 170 &schedule;
170 } 171 }
171}; 172};
172$manager->desc ("[coro manager]"); 173$manager->{desc} = "[coro manager]";
173$manager->prio (PRIO_MAX); 174$manager->prio (PRIO_MAX);
174 175
175=back 176=back
176 177
177=head2 SIMPLE COROUTINE CREATION 178=head2 SIMPLE COROUTINE CREATION
220terminate or join on it (although you are allowed to), and you get a 221terminate or join on it (although you are allowed to), and you get a
221coroutine that might have executed other code already (which can be good 222coroutine that might have executed other code already (which can be good
222or bad :). 223or bad :).
223 224
224On the plus side, this function is faster than creating (and destroying) 225On the plus side, this function is faster than creating (and destroying)
225a completely new coroutine, so if you need a lot of generic coroutines in 226a completly new coroutine, so if you need a lot of generic coroutines in
226quick successsion, use C<async_pool>, not C<async>. 227quick successsion, use C<async_pool>, not C<async>.
227 228
228The code block is executed in an C<eval> context and a warning will be 229The code block is executed in an C<eval> context and a warning will be
229issued in case of an exception instead of terminating the program, as 230issued in case of an exception instead of terminating the program, as
230C<async> does. As the coroutine is being reused, stuff like C<on_destroy> 231C<async> does. As the coroutine is being reused, stuff like C<on_destroy>
234 235
235The priority will be reset to C<0> after each run, tracing will be 236The priority will be reset to C<0> after each run, tracing will be
236disabled, the description will be reset and the default output filehandle 237disabled, the description will be reset and the default output filehandle
237gets restored, so you can change all these. Otherwise the coroutine will 238gets restored, so you can change all these. Otherwise the coroutine will
238be re-used "as-is": most notably if you change other per-coroutine global 239be re-used "as-is": most notably if you change other per-coroutine global
239stuff such as C<$/> you I<must needs> to revert that change, which is most 240stuff such as C<$/> you I<must needs> revert that change, which is most
240simply done by using local as in: C< local $/ >. 241simply done by using local as in: C<< local $/ >>.
241 242
242The pool size is limited to C<8> idle coroutines (this can be adjusted by 243The idle pool size is limited to C<8> idle coroutines (this can be
243changing $Coro::POOL_SIZE), and there can be as many non-idle coros as 244adjusted by changing $Coro::POOL_SIZE), but there can be as many non-idle
244required. 245coros as required.
245 246
246If you are concerned about pooled coroutines growing a lot because a 247If you are concerned about pooled coroutines growing a lot because a
247single C<async_pool> used a lot of stackspace you can e.g. C<async_pool 248single C<async_pool> used a lot of stackspace you can e.g. C<async_pool
248{ terminate }> once per second or so to slowly replenish the pool. In 249{ terminate }> once per second or so to slowly replenish the pool. In
249addition to that, when the stacks used by a handler grows larger than 16kb 250addition to that, when the stacks used by a handler grows larger than 16kb
274 } 275 }
275 } 276 }
276} 277}
277 278
278sub async_pool(&@) { 279sub async_pool(&@) {
279 # this is also inlined into the unlock_scheduler 280 # this is also inlined into the unblock_scheduler
280 my $coro = (pop @async_pool) || new Coro \&pool_handler; 281 my $coro = (pop @async_pool) || new Coro \&pool_handler;
281 282
282 $coro->{_invoke} = [@_]; 283 $coro->{_invoke} = [@_];
283 $coro->ready; 284 $coro->ready;
284 285
440 } else { 441 } else {
441 $self->_cancel; 442 $self->_cancel;
442 } 443 }
443} 444}
444 445
446=item $coroutine->throw ([$scalar])
447
448If C<$throw> is specified and defined, it will be thrown as an exception
449inside the coroutine at the next convenient point in time (usually after
450it gains control at the next schedule/transfer/cede). Otherwise clears the
451exception object.
452
453The exception object will be thrown "as is" with the specified scalar in
454C<$@>, i.e. if it is a string, no line number or newline will be appended
455(unlike with C<die>).
456
457This can be used as a softer means than C<cancel> to ask a coroutine to
458end itself, although there is no guarantee that the exception will lead to
459termination, and if the exception isn't caught it might well end the whole
460program.
461
462You might also think of C<throw> as being the moral equivalent of
463C<kill>ing a coroutine with a signal (in this case, a scalar).
464
445=item $coroutine->join 465=item $coroutine->join
446 466
447Wait until the coroutine terminates and return any values given to the 467Wait until the coroutine terminates and return any values given to the
448C<terminate> or C<cancel> functions. C<join> can be called concurrently 468C<terminate> or C<cancel> functions. C<join> can be called concurrently
449from multiple coroutines, and all will be resumed and given the status 469from multiple coroutines, and all will be resumed and given the status
510higher values mean lower priority, just as in unix). 530higher values mean lower priority, just as in unix).
511 531
512=item $olddesc = $coroutine->desc ($newdesc) 532=item $olddesc = $coroutine->desc ($newdesc)
513 533
514Sets (or gets in case the argument is missing) the description for this 534Sets (or gets in case the argument is missing) the description for this
515coroutine. This is just a free-form string you can associate with a coroutine. 535coroutine. This is just a free-form string you can associate with a
536coroutine.
516 537
517This method simply sets the C<< $coroutine->{desc} >> member to the given string. You 538This method simply sets the C<< $coroutine->{desc} >> member to the given
518can modify this member directly if you wish. 539string. You can modify this member directly if you wish.
519
520=item $coroutine->throw ([$scalar])
521
522If C<$throw> is specified and defined, it will be thrown as an exception
523inside the coroutine at the next convinient point in time (usually after
524it gains control at the next schedule/transfer/cede). Otherwise clears the
525exception object.
526
527The exception object will be thrown "as is" with the specified scalar in
528C<$@>, i.e. if it is a string, no line number or newline will be appended
529(unlike with C<die>).
530
531This can be used as a softer means than C<cancel> to ask a coroutine to
532end itself, although there is no guarentee that the exception will lead to
533termination, and if the exception isn't caught it might well end the whole
534program.
535 540
536=cut 541=cut
537 542
538sub desc { 543sub desc {
539 my $old = $_[0]{desc}; 544 my $old = $_[0]{desc};
641 cede; # for short-lived callbacks, this reduces pressure on the coro pool 646 cede; # for short-lived callbacks, this reduces pressure on the coro pool
642 } 647 }
643 schedule; # sleep well 648 schedule; # sleep well
644 } 649 }
645}; 650};
646$unblock_scheduler->desc ("[unblock_sub scheduler]"); 651$unblock_scheduler->{desc} = "[unblock_sub scheduler]";
647 652
648sub unblock_sub(&) { 653sub unblock_sub(&) {
649 my $cb = shift; 654 my $cb = shift;
650 655
651 sub { 656 sub {
660 665
6611; 6661;
662 667
663=head1 BUGS/LIMITATIONS 668=head1 BUGS/LIMITATIONS
664 669
670=over 4
671
672=item fork with pthread backend
673
674When Coro is compiled using the pthread backend (which isn't recommended
675but required on many BSDs as their libcs are completely broken), then
676coroutines will not survive a fork. There is no known workaround except to
677fix your libc and use a saner backend.
678
679=item perl process emulation ("threads")
680
665This module is not perl-pseudo-thread-safe. You should only ever use this 681This module is not perl-pseudo-thread-safe. You should only ever use this
666module from the same thread (this requirement might be removed in the 682module from the same thread (this requirement might be removed in the
667future to allow per-thread schedulers, but Coro::State does not yet allow 683future to allow per-thread schedulers, but Coro::State does not yet allow
668this). I recommend disabling thread support and using processes, as this 684this). I recommend disabling thread support and using processes, as having
669is much faster and uses less memory. 685the windows process emulation enabled under unix roughly halves perl
686performance, even when not used.
687
688=item coroutine switching not signal safe
689
690You must not switch to another coroutine from within a signal handler
691(only relevant with %SIG - most event libraries provide safe signals).
692
693That means you I<MUST NOT> call any fucntion that might "block" the
694current coroutine - C<cede>, C<schedule> C<< Coro::Semaphore->down >> or
695anything that calls those. Everything else, including calling C<ready>,
696works.
697
698=back
699
670 700
671=head1 SEE ALSO 701=head1 SEE ALSO
672 702
673Event-Loop integration: L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>. 703Event-Loop integration: L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>.
674 704

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