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=head1 NAME |
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|
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Coro::Channel - message queues |
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|
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=head1 SYNOPSIS |
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|
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use Coro::Channel; |
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|
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$q1 = new Coro::Channel <maxsize>; |
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|
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$q1->put("xxx"); |
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print $q1->get; |
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|
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die unless $q1->size; |
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|
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=head1 DESCRIPTION |
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|
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=over 4 |
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|
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=cut |
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|
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package Coro::Channel; |
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|
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use Coro::Process (); |
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|
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$VERSION = 0.01; |
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|
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=item $q = new Coro:Channel $maxsize |
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|
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Create a new channel with the given maximum size (unlimited if C<maxsize> |
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is omitted). Stating a size of zero gives you a traditional channel, i.e. |
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a queue that can store only a single element. |
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|
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=cut |
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|
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sub new { |
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# [\@contents, $queue, $maxsize]; |
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bless [[], [], $_[1]], $_[0]; |
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} |
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|
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=item $q->put($scalar) |
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|
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Put the given scalar into the queue. |
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|
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=cut |
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|
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sub put { |
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push @{$_[0][0]}, $_[1]; |
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(pop @{$_[0][1]})->ready if @{$_[0][1]}; |
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&Coro::Process::yield if defined $_[0][2] && @{$_[0][0]} > $_[0][2]; |
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} |
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|
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=item $q->get |
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|
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Return the next element from the queue, waiting if necessary. |
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|
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=cut |
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|
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sub get { |
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while (!@{$_[0][0]}) { |
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push @{$_[0][1]}, $Coro::Process::current; |
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&Coro::Process::schedule; |
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} |
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shift @{$_[0][0]}; |
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} |
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|
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=item $q->size |
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|
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Return the number of elements waiting to be consumed. Please note that: |
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|
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if ($q->size) { |
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my $data = $q->get; |
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} |
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|
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is NOT a race condition but works fine. |
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|
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=cut |
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|
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sub size { |
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scalar @{$_[0][0]}; |
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} |
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|
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1; |
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|
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=back |
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|
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=head1 AUTHOR |
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|
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Marc Lehmann <pcg@goof.com> |
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http://www.goof.com/pcg/marc/ |
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|
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=cut |
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|
