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=head1 NAME |
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Coro - coroutine process abstraction |
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=head1 SYNOPSIS |
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use Coro; |
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async { |
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# some asynchronous thread of execution |
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print "2\n"; |
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cede; # yield back to main |
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print "4\n"; |
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}; |
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print "1\n"; |
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cede; # yield to coroutine |
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print "3\n"; |
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cede; # and again |
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# use locking |
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use Coro::Semaphore; |
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my $lock = new Coro::Semaphore; |
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my $locked; |
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$lock->down; |
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$locked = 1; |
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$lock->up; |
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|
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=head1 DESCRIPTION |
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This module collection manages coroutines. Coroutines are similar to |
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threads but don't (in general) run in parallel at the same time even |
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on SMP machines. The specific flavor of coroutine used in this module |
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also guarantees you that it will not switch between coroutines unless |
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necessary, at easily-identified points in your program, so locking and |
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parallel access are rarely an issue, making coroutine programming much |
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safer and easier than threads programming. |
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|
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Unlike a normal perl program, however, coroutines allow you to have |
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multiple running interpreters that share data, which is especially useful |
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to code pseudo-parallel processes and for event-based programming, such as |
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multiple HTTP-GET requests running concurrently. See L<Coro::AnyEvent> to |
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learn more. |
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|
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Coroutines are also useful because Perl has no support for threads (the so |
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called "threads" that perl offers are nothing more than the (bad) process |
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emulation coming from the Windows platform: On standard operating systems |
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they serve no purpose whatsoever, except by making your programs slow and |
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making them use a lot of memory. Best disable them when building perl, or |
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aks your software vendor/distributor to do it for you). |
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In this module, coroutines are defined as "callchain + lexical variables + |
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@_ + $_ + $@ + $/ + C stack), that is, a coroutine has its own callchain, |
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its own set of lexicals and its own set of perls most important global |
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variables (see L<Coro::State> for more configuration). |
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|
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=cut |
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package Coro; |
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use strict; |
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no warnings "uninitialized"; |
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|
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use Coro::State; |
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use base qw(Coro::State Exporter); |
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|
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our $idle; # idle handler |
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our $main; # main coroutine |
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our $current; # current coroutine |
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|
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our $VERSION = 4.748; |
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|
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our @EXPORT = qw(async async_pool cede schedule terminate current unblock_sub); |
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our %EXPORT_TAGS = ( |
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prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)], |
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); |
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our @EXPORT_OK = (@{$EXPORT_TAGS{prio}}, qw(nready)); |
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|
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=over 4 |
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=item $Coro::main |
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This variable stores the coroutine object that represents the main |
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program. While you cna C<ready> it and do most other things you can do to |
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coroutines, it is mainly useful to compare again C<$Coro::current>, to see |
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whether you are running in the main program or not. |
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|
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=cut |
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$main = new Coro; |
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=item $Coro::current |
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The coroutine object representing the current coroutine (the last |
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coroutine that the Coro scheduler switched to). The initial value is |
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C<$main> (of course). |
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This variable is B<strictly> I<read-only>. You can take copies of the |
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value stored in it and use it as any other coroutine object, but you must |
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not otherwise modify the variable itself. |
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|
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=cut |
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$main->{desc} = "[main::]"; |
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# maybe some other module used Coro::Specific before... |
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$main->{_specific} = $current->{_specific} |
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if $current; |
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|
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_set_current $main; |
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sub current() { $current } # [DEPRECATED] |
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|
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=item $Coro::idle |
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|
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This variable is mainly useful to integrate Coro into event loops. It is |
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usually better to rely on L<Coro::AnyEvent> or LC<Coro::EV>, as this is |
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pretty low-level functionality. |
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This variable stores a callback that is called whenever the scheduler |
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finds no ready coroutines to run. The default implementation prints |
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"FATAL: deadlock detected" and exits, because the program has no other way |
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to continue. |
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This hook is overwritten by modules such as C<Coro::Timer> and |
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C<Coro::AnyEvent> to wait on an external event that hopefully wake up a |
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coroutine so the scheduler can run it. |
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Note that the callback I<must not>, under any circumstances, block |
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the current coroutine. Normally, this is achieved by having an "idle |
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coroutine" that calls the event loop and then blocks again, and then |
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readying that coroutine in the idle handler. |
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See L<Coro::Event> or L<Coro::AnyEvent> for examples of using this |
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technique. |
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Please note that if your callback recursively invokes perl (e.g. for event |
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handlers), then it must be prepared to be called recursively itself. |
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|
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=cut |
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$idle = sub { |
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require Carp; |
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Carp::croak ("FATAL: deadlock detected"); |
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}; |
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sub _cancel { |
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my ($self) = @_; |
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# free coroutine data and mark as destructed |
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$self->_destroy |
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or return; |
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# call all destruction callbacks |
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$_->(@{$self->{_status}}) |
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for @{(delete $self->{_on_destroy}) || []}; |
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} |
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# this coroutine is necessary because a coroutine |
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# cannot destroy itself. |
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my @destroy; |
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my $manager; |
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$manager = new Coro sub { |
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while () { |
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(shift @destroy)->_cancel |
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while @destroy; |
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&schedule; |
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} |
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}; |
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$manager->desc ("[coro manager]"); |
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$manager->prio (PRIO_MAX); |
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=back |
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|
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=head2 SIMPLE COROUTINE CREATION |
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=over 4 |
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=item async { ... } [@args...] |
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Create a new coroutine and return it's coroutine object (usually |
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unused). The coroutine will be put into the ready queue, so |
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it will start running automatically on the next scheduler run. |
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The first argument is a codeblock/closure that should be executed in the |
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coroutine. When it returns argument returns the coroutine is automatically |
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terminated. |
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The remaining arguments are passed as arguments to the closure. |
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See the C<Coro::State::new> constructor for info about the coroutine |
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environment in which coroutines are executed. |
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Calling C<exit> in a coroutine will do the same as calling exit outside |
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the coroutine. Likewise, when the coroutine dies, the program will exit, |
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just as it would in the main program. |
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If you do not want that, you can provide a default C<die> handler, or |
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simply avoid dieing (by use of C<eval>). |
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Example: Create a new coroutine that just prints its arguments. |
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async { |
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print "@_\n"; |
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} 1,2,3,4; |
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=cut |
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sub async(&@) { |
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my $coro = new Coro @_; |
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$coro->ready; |
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$coro |
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} |
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=item async_pool { ... } [@args...] |
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Similar to C<async>, but uses a coroutine pool, so you should not call |
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terminate or join on it (although you are allowed to), and you get a |
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coroutine that might have executed other code already (which can be good |
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or bad :). |
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On the plus side, this function is faster than creating (and destroying) |
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a completely new coroutine, so if you need a lot of generic coroutines in |
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quick successsion, use C<async_pool>, not C<async>. |
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The code block is executed in an C<eval> context and a warning will be |
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issued in case of an exception instead of terminating the program, as |
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C<async> does. As the coroutine is being reused, stuff like C<on_destroy> |
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will not work in the expected way, unless you call terminate or cancel, |
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which somehow defeats the purpose of pooling (but is fine in the |
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exceptional case). |
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|
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The priority will be reset to C<0> after each run, tracing will be |
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disabled, the description will be reset and the default output filehandle |
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gets restored, so you can change all these. Otherwise the coroutine will |
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be re-used "as-is": most notably if you change other per-coroutine global |
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stuff such as C<$/> you I<must needs> to revert that change, which is most |
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simply done by using local as in: C< local $/ >. |
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|
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The pool size is limited to C<8> idle coroutines (this can be adjusted by |
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changing $Coro::POOL_SIZE), and there can be as many non-idle coros as |
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required. |
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If you are concerned about pooled coroutines growing a lot because a |
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single C<async_pool> used a lot of stackspace you can e.g. C<async_pool |
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{ terminate }> once per second or so to slowly replenish the pool. In |
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addition to that, when the stacks used by a handler grows larger than 16kb |
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(adjustable via $Coro::POOL_RSS) it will also be destroyed. |
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|
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=cut |
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our $POOL_SIZE = 8; |
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our $POOL_RSS = 16 * 1024; |
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our @async_pool; |
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sub pool_handler { |
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my $cb; |
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while () { |
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eval { |
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while () { |
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_pool_1 $cb; |
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&$cb; |
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_pool_2 $cb; |
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&schedule; |
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} |
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}; |
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|
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if ($@) { |
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last if $@ eq "\3async_pool terminate\2\n"; |
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warn $@; |
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} |
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} |
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} |
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sub async_pool(&@) { |
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# this is also inlined into the unlock_scheduler |
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my $coro = (pop @async_pool) || new Coro \&pool_handler; |
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$coro->{_invoke} = [@_]; |
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$coro->ready; |
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$coro |
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} |
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=back |
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=head2 STATIC METHODS |
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Static methods are actually functions that operate on the current coroutine. |
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=over 4 |
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=item schedule |
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|
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Calls the scheduler. The scheduler will find the next coroutine that is |
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to be run from the ready queue and switches to it. The next coroutine |
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to be run is simply the one with the highest priority that is longest |
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in its ready queue. If there is no coroutine ready, it will clal the |
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C<$Coro::idle> hook. |
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Please note that the current coroutine will I<not> be put into the ready |
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queue, so calling this function usually means you will never be called |
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again unless something else (e.g. an event handler) calls C<< ->ready >>, |
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thus waking you up. |
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This makes C<schedule> I<the> generic method to use to block the current |
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coroutine and wait for events: first you remember the current coroutine in |
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a variable, then arrange for some callback of yours to call C<< ->ready |
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>> on that once some event happens, and last you call C<schedule> to put |
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yourself to sleep. Note that a lot of things can wake your coroutine up, |
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so you need to check whether the event indeed happened, e.g. by storing the |
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status in a variable. |
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|
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The canonical way to wait on external events is this: |
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|
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{ |
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# remember current coroutine |
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my $current = $Coro::current; |
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# register a hypothetical event handler |
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on_event_invoke sub { |
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# wake up sleeping coroutine |
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$current->ready; |
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undef $current; |
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}; |
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# call schedule until event occurred. |
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# in case we are woken up for other reasons |
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# (current still defined), loop. |
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Coro::schedule while $current; |
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} |
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|
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1.22 |
=item cede |
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1.1 |
|
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"Cede" to other coroutines. This function puts the current coroutine into |
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the ready queue and calls C<schedule>, which has the effect of giving |
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up the current "timeslice" to other coroutines of the same or higher |
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priority. Once your coroutine gets its turn again it will automatically be |
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resumed. |
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This function is often called C<yield> in other languages. |
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|
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=item Coro::cede_notself |
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Works like cede, but is not exported by default and will cede to I<any> |
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coroutine, regardless of priority. This is useful sometimes to ensure |
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progress is made. |
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|
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1.40 |
=item terminate [arg...] |
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|
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Terminates the current coroutine with the given status values (see L<cancel>). |
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1.13 |
|
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=item killall |
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Kills/terminates/cancels all coroutines except the currently running |
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one. This is useful after a fork, either in the child or the parent, as |
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usually only one of them should inherit the running coroutines. |
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|
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Note that while this will try to free some of the main programs resources, |
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you cannot free all of them, so if a coroutine that is not the main |
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program calls this function, there will be some one-time resource leak. |
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|
367 |
root |
1.1 |
=cut |
368 |
|
|
|
369 |
root |
1.8 |
sub terminate { |
370 |
pcg |
1.59 |
$current->cancel (@_); |
371 |
root |
1.1 |
} |
372 |
root |
1.6 |
|
373 |
root |
1.141 |
sub killall { |
374 |
|
|
for (Coro::State::list) { |
375 |
|
|
$_->cancel |
376 |
|
|
if $_ != $current && UNIVERSAL::isa $_, "Coro"; |
377 |
|
|
} |
378 |
|
|
} |
379 |
|
|
|
380 |
root |
1.8 |
=back |
381 |
|
|
|
382 |
root |
1.92 |
=head2 COROUTINE METHODS |
383 |
root |
1.8 |
|
384 |
root |
1.181 |
These are the methods you can call on coroutine objects (or to create |
385 |
|
|
them). |
386 |
root |
1.6 |
|
387 |
root |
1.8 |
=over 4 |
388 |
|
|
|
389 |
root |
1.13 |
=item new Coro \&sub [, @args...] |
390 |
root |
1.8 |
|
391 |
root |
1.181 |
Create a new coroutine and return it. When the sub returns, the coroutine |
392 |
root |
1.40 |
automatically terminates as if C<terminate> with the returned values were |
393 |
root |
1.181 |
called. To make the coroutine run you must first put it into the ready |
394 |
|
|
queue by calling the ready method. |
395 |
root |
1.13 |
|
396 |
root |
1.145 |
See C<async> and C<Coro::State::new> for additional info about the |
397 |
|
|
coroutine environment. |
398 |
root |
1.89 |
|
399 |
root |
1.6 |
=cut |
400 |
|
|
|
401 |
root |
1.94 |
sub _run_coro { |
402 |
root |
1.13 |
terminate &{+shift}; |
403 |
|
|
} |
404 |
|
|
|
405 |
root |
1.8 |
sub new { |
406 |
|
|
my $class = shift; |
407 |
root |
1.83 |
|
408 |
root |
1.94 |
$class->SUPER::new (\&_run_coro, @_) |
409 |
root |
1.8 |
} |
410 |
root |
1.6 |
|
411 |
root |
1.92 |
=item $success = $coroutine->ready |
412 |
root |
1.1 |
|
413 |
root |
1.181 |
Put the given coroutine into the end of its ready queue (there is one |
414 |
|
|
queue for each priority) and return true. If the coroutine is already in |
415 |
|
|
the ready queue, do nothing and return false. |
416 |
|
|
|
417 |
|
|
This ensures that the scheduler will resume this coroutine automatically |
418 |
|
|
once all the coroutines of higher priority and all coroutines of the same |
419 |
|
|
priority that were put into the ready queue earlier have been resumed. |
420 |
root |
1.1 |
|
421 |
root |
1.92 |
=item $is_ready = $coroutine->is_ready |
422 |
root |
1.90 |
|
423 |
root |
1.196 |
Return whether the coroutine is currently the ready queue or not, |
424 |
root |
1.28 |
|
425 |
root |
1.92 |
=item $coroutine->cancel (arg...) |
426 |
root |
1.28 |
|
427 |
root |
1.92 |
Terminates the given coroutine and makes it return the given arguments as |
428 |
root |
1.103 |
status (default: the empty list). Never returns if the coroutine is the |
429 |
|
|
current coroutine. |
430 |
root |
1.28 |
|
431 |
|
|
=cut |
432 |
|
|
|
433 |
|
|
sub cancel { |
434 |
pcg |
1.59 |
my $self = shift; |
435 |
root |
1.142 |
$self->{_status} = [@_]; |
436 |
root |
1.103 |
|
437 |
|
|
if ($current == $self) { |
438 |
|
|
push @destroy, $self; |
439 |
|
|
$manager->ready; |
440 |
|
|
&schedule while 1; |
441 |
|
|
} else { |
442 |
|
|
$self->_cancel; |
443 |
|
|
} |
444 |
root |
1.40 |
} |
445 |
|
|
|
446 |
root |
1.92 |
=item $coroutine->join |
447 |
root |
1.40 |
|
448 |
|
|
Wait until the coroutine terminates and return any values given to the |
449 |
root |
1.143 |
C<terminate> or C<cancel> functions. C<join> can be called concurrently |
450 |
root |
1.181 |
from multiple coroutines, and all will be resumed and given the status |
451 |
|
|
return once the C<$coroutine> terminates. |
452 |
root |
1.40 |
|
453 |
|
|
=cut |
454 |
|
|
|
455 |
|
|
sub join { |
456 |
|
|
my $self = shift; |
457 |
root |
1.103 |
|
458 |
root |
1.142 |
unless ($self->{_status}) { |
459 |
root |
1.103 |
my $current = $current; |
460 |
|
|
|
461 |
root |
1.142 |
push @{$self->{_on_destroy}}, sub { |
462 |
root |
1.103 |
$current->ready; |
463 |
|
|
undef $current; |
464 |
|
|
}; |
465 |
|
|
|
466 |
|
|
&schedule while $current; |
467 |
root |
1.40 |
} |
468 |
root |
1.103 |
|
469 |
root |
1.142 |
wantarray ? @{$self->{_status}} : $self->{_status}[0]; |
470 |
root |
1.31 |
} |
471 |
|
|
|
472 |
root |
1.101 |
=item $coroutine->on_destroy (\&cb) |
473 |
|
|
|
474 |
|
|
Registers a callback that is called when this coroutine gets destroyed, |
475 |
|
|
but before it is joined. The callback gets passed the terminate arguments, |
476 |
root |
1.181 |
if any, and I<must not> die, under any circumstances. |
477 |
root |
1.101 |
|
478 |
|
|
=cut |
479 |
|
|
|
480 |
|
|
sub on_destroy { |
481 |
|
|
my ($self, $cb) = @_; |
482 |
|
|
|
483 |
root |
1.142 |
push @{ $self->{_on_destroy} }, $cb; |
484 |
root |
1.101 |
} |
485 |
|
|
|
486 |
root |
1.92 |
=item $oldprio = $coroutine->prio ($newprio) |
487 |
root |
1.31 |
|
488 |
root |
1.41 |
Sets (or gets, if the argument is missing) the priority of the |
489 |
root |
1.92 |
coroutine. Higher priority coroutines get run before lower priority |
490 |
|
|
coroutines. Priorities are small signed integers (currently -4 .. +3), |
491 |
root |
1.41 |
that you can refer to using PRIO_xxx constants (use the import tag :prio |
492 |
|
|
to get then): |
493 |
root |
1.31 |
|
494 |
|
|
PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN |
495 |
|
|
3 > 1 > 0 > -1 > -3 > -4 |
496 |
|
|
|
497 |
|
|
# set priority to HIGH |
498 |
|
|
current->prio(PRIO_HIGH); |
499 |
|
|
|
500 |
|
|
The idle coroutine ($Coro::idle) always has a lower priority than any |
501 |
|
|
existing coroutine. |
502 |
|
|
|
503 |
root |
1.92 |
Changing the priority of the current coroutine will take effect immediately, |
504 |
|
|
but changing the priority of coroutines in the ready queue (but not |
505 |
root |
1.31 |
running) will only take effect after the next schedule (of that |
506 |
root |
1.92 |
coroutine). This is a bug that will be fixed in some future version. |
507 |
root |
1.31 |
|
508 |
root |
1.92 |
=item $newprio = $coroutine->nice ($change) |
509 |
root |
1.31 |
|
510 |
|
|
Similar to C<prio>, but subtract the given value from the priority (i.e. |
511 |
|
|
higher values mean lower priority, just as in unix). |
512 |
|
|
|
513 |
root |
1.92 |
=item $olddesc = $coroutine->desc ($newdesc) |
514 |
root |
1.41 |
|
515 |
|
|
Sets (or gets in case the argument is missing) the description for this |
516 |
root |
1.92 |
coroutine. This is just a free-form string you can associate with a coroutine. |
517 |
root |
1.41 |
|
518 |
root |
1.142 |
This method simply sets the C<< $coroutine->{desc} >> member to the given string. You |
519 |
|
|
can modify this member directly if you wish. |
520 |
|
|
|
521 |
root |
1.150 |
=item $coroutine->throw ([$scalar]) |
522 |
|
|
|
523 |
|
|
If C<$throw> is specified and defined, it will be thrown as an exception |
524 |
|
|
inside the coroutine at the next convinient point in time (usually after |
525 |
|
|
it gains control at the next schedule/transfer/cede). Otherwise clears the |
526 |
|
|
exception object. |
527 |
|
|
|
528 |
|
|
The exception object will be thrown "as is" with the specified scalar in |
529 |
|
|
C<$@>, i.e. if it is a string, no line number or newline will be appended |
530 |
|
|
(unlike with C<die>). |
531 |
|
|
|
532 |
|
|
This can be used as a softer means than C<cancel> to ask a coroutine to |
533 |
|
|
end itself, although there is no guarentee that the exception will lead to |
534 |
|
|
termination, and if the exception isn't caught it might well end the whole |
535 |
|
|
program. |
536 |
|
|
|
537 |
root |
1.41 |
=cut |
538 |
|
|
|
539 |
|
|
sub desc { |
540 |
|
|
my $old = $_[0]{desc}; |
541 |
|
|
$_[0]{desc} = $_[1] if @_ > 1; |
542 |
|
|
$old; |
543 |
root |
1.8 |
} |
544 |
root |
1.1 |
|
545 |
root |
1.8 |
=back |
546 |
root |
1.2 |
|
547 |
root |
1.97 |
=head2 GLOBAL FUNCTIONS |
548 |
root |
1.92 |
|
549 |
|
|
=over 4 |
550 |
|
|
|
551 |
root |
1.97 |
=item Coro::nready |
552 |
|
|
|
553 |
|
|
Returns the number of coroutines that are currently in the ready state, |
554 |
root |
1.181 |
i.e. that can be switched to by calling C<schedule> directory or |
555 |
|
|
indirectly. The value C<0> means that the only runnable coroutine is the |
556 |
|
|
currently running one, so C<cede> would have no effect, and C<schedule> |
557 |
|
|
would cause a deadlock unless there is an idle handler that wakes up some |
558 |
|
|
coroutines. |
559 |
root |
1.97 |
|
560 |
root |
1.103 |
=item my $guard = Coro::guard { ... } |
561 |
|
|
|
562 |
root |
1.119 |
This creates and returns a guard object. Nothing happens until the object |
563 |
root |
1.103 |
gets destroyed, in which case the codeblock given as argument will be |
564 |
|
|
executed. This is useful to free locks or other resources in case of a |
565 |
|
|
runtime error or when the coroutine gets canceled, as in both cases the |
566 |
|
|
guard block will be executed. The guard object supports only one method, |
567 |
|
|
C<< ->cancel >>, which will keep the codeblock from being executed. |
568 |
|
|
|
569 |
|
|
Example: set some flag and clear it again when the coroutine gets canceled |
570 |
|
|
or the function returns: |
571 |
|
|
|
572 |
|
|
sub do_something { |
573 |
|
|
my $guard = Coro::guard { $busy = 0 }; |
574 |
|
|
$busy = 1; |
575 |
|
|
|
576 |
|
|
# do something that requires $busy to be true |
577 |
|
|
} |
578 |
|
|
|
579 |
|
|
=cut |
580 |
|
|
|
581 |
|
|
sub guard(&) { |
582 |
|
|
bless \(my $cb = $_[0]), "Coro::guard" |
583 |
|
|
} |
584 |
|
|
|
585 |
|
|
sub Coro::guard::cancel { |
586 |
|
|
${$_[0]} = sub { }; |
587 |
|
|
} |
588 |
|
|
|
589 |
|
|
sub Coro::guard::DESTROY { |
590 |
|
|
${$_[0]}->(); |
591 |
|
|
} |
592 |
|
|
|
593 |
|
|
|
594 |
root |
1.92 |
=item unblock_sub { ... } |
595 |
|
|
|
596 |
|
|
This utility function takes a BLOCK or code reference and "unblocks" it, |
597 |
root |
1.181 |
returning a new coderef. Unblocking means that calling the new coderef |
598 |
|
|
will return immediately without blocking, returning nothing, while the |
599 |
|
|
original code ref will be called (with parameters) from within another |
600 |
|
|
coroutine. |
601 |
root |
1.92 |
|
602 |
root |
1.124 |
The reason this function exists is that many event libraries (such as the |
603 |
root |
1.92 |
venerable L<Event|Event> module) are not coroutine-safe (a weaker form |
604 |
|
|
of thread-safety). This means you must not block within event callbacks, |
605 |
root |
1.181 |
otherwise you might suffer from crashes or worse. The only event library |
606 |
|
|
currently known that is safe to use without C<unblock_sub> is L<EV>. |
607 |
root |
1.92 |
|
608 |
|
|
This function allows your callbacks to block by executing them in another |
609 |
|
|
coroutine where it is safe to block. One example where blocking is handy |
610 |
|
|
is when you use the L<Coro::AIO|Coro::AIO> functions to save results to |
611 |
root |
1.181 |
disk, for example. |
612 |
root |
1.92 |
|
613 |
|
|
In short: simply use C<unblock_sub { ... }> instead of C<sub { ... }> when |
614 |
|
|
creating event callbacks that want to block. |
615 |
|
|
|
616 |
root |
1.181 |
If your handler does not plan to block (e.g. simply sends a message to |
617 |
|
|
another coroutine, or puts some other coroutine into the ready queue), |
618 |
|
|
there is no reason to use C<unblock_sub>. |
619 |
|
|
|
620 |
root |
1.183 |
Note that you also need to use C<unblock_sub> for any other callbacks that |
621 |
|
|
are indirectly executed by any C-based event loop. For example, when you |
622 |
|
|
use a module that uses L<AnyEvent> (and you use L<Coro::AnyEvent>) and it |
623 |
|
|
provides callbacks that are the result of some event callback, then you |
624 |
|
|
must not block either, or use C<unblock_sub>. |
625 |
|
|
|
626 |
root |
1.92 |
=cut |
627 |
|
|
|
628 |
|
|
our @unblock_queue; |
629 |
|
|
|
630 |
root |
1.105 |
# we create a special coro because we want to cede, |
631 |
|
|
# to reduce pressure on the coro pool (because most callbacks |
632 |
|
|
# return immediately and can be reused) and because we cannot cede |
633 |
|
|
# inside an event callback. |
634 |
root |
1.132 |
our $unblock_scheduler = new Coro sub { |
635 |
root |
1.92 |
while () { |
636 |
|
|
while (my $cb = pop @unblock_queue) { |
637 |
root |
1.105 |
# this is an inlined copy of async_pool |
638 |
root |
1.134 |
my $coro = (pop @async_pool) || new Coro \&pool_handler; |
639 |
root |
1.105 |
|
640 |
|
|
$coro->{_invoke} = $cb; |
641 |
|
|
$coro->ready; |
642 |
|
|
cede; # for short-lived callbacks, this reduces pressure on the coro pool |
643 |
root |
1.92 |
} |
644 |
root |
1.105 |
schedule; # sleep well |
645 |
root |
1.92 |
} |
646 |
|
|
}; |
647 |
root |
1.132 |
$unblock_scheduler->desc ("[unblock_sub scheduler]"); |
648 |
root |
1.92 |
|
649 |
|
|
sub unblock_sub(&) { |
650 |
|
|
my $cb = shift; |
651 |
|
|
|
652 |
|
|
sub { |
653 |
root |
1.105 |
unshift @unblock_queue, [$cb, @_]; |
654 |
root |
1.92 |
$unblock_scheduler->ready; |
655 |
|
|
} |
656 |
|
|
} |
657 |
|
|
|
658 |
|
|
=back |
659 |
|
|
|
660 |
root |
1.8 |
=cut |
661 |
root |
1.2 |
|
662 |
root |
1.8 |
1; |
663 |
root |
1.14 |
|
664 |
root |
1.17 |
=head1 BUGS/LIMITATIONS |
665 |
root |
1.14 |
|
666 |
root |
1.181 |
This module is not perl-pseudo-thread-safe. You should only ever use this |
667 |
|
|
module from the same thread (this requirement might be removed in the |
668 |
|
|
future to allow per-thread schedulers, but Coro::State does not yet allow |
669 |
|
|
this). I recommend disabling thread support and using processes, as this |
670 |
|
|
is much faster and uses less memory. |
671 |
root |
1.9 |
|
672 |
|
|
=head1 SEE ALSO |
673 |
|
|
|
674 |
root |
1.181 |
Event-Loop integration: L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>. |
675 |
root |
1.152 |
|
676 |
|
|
Debugging: L<Coro::Debug>. |
677 |
|
|
|
678 |
|
|
Support/Utility: L<Coro::Specific>, L<Coro::Util>. |
679 |
root |
1.67 |
|
680 |
|
|
Locking/IPC: L<Coro::Signal>, L<Coro::Channel>, L<Coro::Semaphore>, L<Coro::SemaphoreSet>, L<Coro::RWLock>. |
681 |
|
|
|
682 |
root |
1.181 |
IO/Timers: L<Coro::Timer>, L<Coro::Handle>, L<Coro::Socket>, L<Coro::AIO>. |
683 |
|
|
|
684 |
|
|
Compatibility: L<Coro::LWP>, L<Coro::BDB>, L<Coro::Storable>, L<Coro::Select>. |
685 |
root |
1.152 |
|
686 |
root |
1.181 |
XS API: L<Coro::MakeMaker>. |
687 |
root |
1.67 |
|
688 |
root |
1.181 |
Low level Configuration, Coroutine Environment: L<Coro::State>. |
689 |
root |
1.1 |
|
690 |
|
|
=head1 AUTHOR |
691 |
|
|
|
692 |
root |
1.66 |
Marc Lehmann <schmorp@schmorp.de> |
693 |
root |
1.64 |
http://home.schmorp.de/ |
694 |
root |
1.1 |
|
695 |
|
|
=cut |
696 |
|
|
|