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Comparing cvsroot/Coro/Coro.pm (file contents):
Revision 1.269 by root, Thu Oct 1 23:25:03 2009 UTC vs.
Revision 1.277 by root, Mon May 17 16:51:44 2010 UTC

… …
81 81
82our $idle; # idle handler 82our $idle; # idle handler
83our $main; # main coro 83our $main; # main coro
84our $current; # current coro 84our $current; # current coro
85 85
86our $VERSION = 5.17; 86our $VERSION = 5.23;
87 87
88our @EXPORT = qw(async async_pool cede schedule terminate current unblock_sub); 88our @EXPORT = qw(async async_pool cede schedule terminate current unblock_sub rouse_cb rouse_wait);
89our %EXPORT_TAGS = ( 89our %EXPORT_TAGS = (
90 prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)], 90 prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],
91); 91);
92our @EXPORT_OK = (@{$EXPORT_TAGS{prio}}, qw(nready)); 92our @EXPORT_OK = (@{$EXPORT_TAGS{prio}}, qw(nready));
93 93
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124 124
125This variable is mainly useful to integrate Coro into event loops. It is 125This variable is mainly useful to integrate Coro into event loops. It is
126usually better to rely on L<Coro::AnyEvent> or L<Coro::EV>, as this is 126usually better to rely on L<Coro::AnyEvent> or L<Coro::EV>, as this is
127pretty low-level functionality. 127pretty low-level functionality.
128 128
129This variable stores either a Coro object or a callback. 129This variable stores a Coro object that is put into the ready queue when
130there are no other ready threads (without invoking any ready hooks).
130 131
131If it is a callback, the it is called whenever the scheduler finds no 132The default implementation dies with "FATAL: deadlock detected.", followed
132ready coros to run. The default implementation prints "FATAL: 133by a thread listing, because the program has no other way to continue.
133deadlock detected" and exits, because the program has no other way to
134continue.
135
136If it is a coro object, then this object will be readied (without
137invoking any ready hooks, however) when the scheduler finds no other ready
138coros to run.
139 134
140This hook is overwritten by modules such as C<Coro::EV> and 135This hook is overwritten by modules such as C<Coro::EV> and
141C<Coro::AnyEvent> to wait on an external event that hopefully wake up a 136C<Coro::AnyEvent> to wait on an external event that hopefully wake up a
142coro so the scheduler can run it. 137coro so the scheduler can run it.
143 138
144Note that the callback I<must not>, under any circumstances, block
145the current coro. Normally, this is achieved by having an "idle
146coro" that calls the event loop and then blocks again, and then
147readying that coro in the idle handler, or by simply placing the idle
148coro in this variable.
149
150See L<Coro::Event> or L<Coro::AnyEvent> for examples of using this 139See L<Coro::EV> or L<Coro::AnyEvent> for examples of using this technique.
151technique.
152 140
153Please note that if your callback recursively invokes perl (e.g. for event
154handlers), then it must be prepared to be called recursively itself.
155
156=cut 141=cut
157 142
158$idle = sub { 143# ||= because other modules could have provided their own by now
159 Carp::confess ("FATAL: deadlock detected"); 144$idle ||= new Coro sub {
145 require Coro::Debug;
146 die "FATAL: deadlock detected.\n"
147 . Coro::Debug::ps_listing ();
160}; 148};
161 149
162# this coro is necessary because a coro 150# this coro is necessary because a coro
163# cannot destroy itself. 151# cannot destroy itself.
164our @destroy; 152our @destroy;
… …
272=item schedule 260=item schedule
273 261
274Calls the scheduler. The scheduler will find the next coro that is 262Calls the scheduler. The scheduler will find the next coro that is
275to be run from the ready queue and switches to it. The next coro 263to be run from the ready queue and switches to it. The next coro
276to be run is simply the one with the highest priority that is longest 264to be run is simply the one with the highest priority that is longest
277in its ready queue. If there is no coro ready, it will clal the 265in its ready queue. If there is no coro ready, it will call the
278C<$Coro::idle> hook. 266C<$Coro::idle> hook.
279 267
280Please note that the current coro will I<not> be put into the ready 268Please note that the current coro will I<not> be put into the ready
281queue, so calling this function usually means you will never be called 269queue, so calling this function usually means you will never be called
282again unless something else (e.g. an event handler) calls C<< ->ready >>, 270again unless something else (e.g. an event handler) calls C<< ->ready >>,
… …
678venerable L<Event|Event> module) are not thread-safe (a weaker form 666venerable L<Event|Event> module) are not thread-safe (a weaker form
679of reentrancy). This means you must not block within event callbacks, 667of reentrancy). This means you must not block within event callbacks,
680otherwise you might suffer from crashes or worse. The only event library 668otherwise you might suffer from crashes or worse. The only event library
681currently known that is safe to use without C<unblock_sub> is L<EV>. 669currently known that is safe to use without C<unblock_sub> is L<EV>.
682 670
671Coro will try to catch you when you block in the event loop
672("FATAL:$Coro::IDLE blocked itself"), but this is just best effort and
673only works when you do not run your own event loop.
674
683This function allows your callbacks to block by executing them in another 675This function allows your callbacks to block by executing them in another
684coro where it is safe to block. One example where blocking is handy 676coro where it is safe to block. One example where blocking is handy
685is when you use the L<Coro::AIO|Coro::AIO> functions to save results to 677is when you use the L<Coro::AIO|Coro::AIO> functions to save results to
686disk, for example. 678disk, for example.
687 679
… …
728 unshift @unblock_queue, [$cb, @_]; 720 unshift @unblock_queue, [$cb, @_];
729 $unblock_scheduler->ready; 721 $unblock_scheduler->ready;
730 } 722 }
731} 723}
732 724
733=item $cb = Coro::rouse_cb 725=item $cb = rouse_cb
734 726
735Create and return a "rouse callback". That's a code reference that, 727Create and return a "rouse callback". That's a code reference that,
736when called, will remember a copy of its arguments and notify the owner 728when called, will remember a copy of its arguments and notify the owner
737coro of the callback. 729coro of the callback.
738 730
739See the next function. 731See the next function.
740 732
741=item @args = Coro::rouse_wait [$cb] 733=item @args = rouse_wait [$cb]
742 734
743Wait for the specified rouse callback (or the last one that was created in 735Wait for the specified rouse callback (or the last one that was created in
744this coro). 736this coro).
745 737
746As soon as the callback is invoked (or when the callback was invoked 738As soon as the callback is invoked (or when the callback was invoked
… …
843the windows process emulation enabled under unix roughly halves perl 835the windows process emulation enabled under unix roughly halves perl
844performance, even when not used. 836performance, even when not used.
845 837
846=item coro switching is not signal safe 838=item coro switching is not signal safe
847 839
848You must not switch to another coro from within a signal handler 840You must not switch to another coro from within a signal handler (only
849(only relevant with %SIG - most event libraries provide safe signals). 841relevant with %SIG - most event libraries provide safe signals), I<unless>
842you are sure you are not interrupting a Coro function.
850 843
851That means you I<MUST NOT> call any function that might "block" the 844That means you I<MUST NOT> call any function that might "block" the
852current coro - C<cede>, C<schedule> C<< Coro::Semaphore->down >> or 845current coro - C<cede>, C<schedule> C<< Coro::Semaphore->down >> or
853anything that calls those. Everything else, including calling C<ready>, 846anything that calls those. Everything else, including calling C<ready>,
854works. 847works.

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