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=head1 NAME |
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Net::SNMP::EV - adaptor to integrate Net::SNMP into the EV event loop. |
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=head1 SYNOPSIS |
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|
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use EV; |
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use Net::SNMP; |
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use Net::SNMP::EV; |
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# just use Net::SNMP and EV as you like: |
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|
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... start non-blocking snmp request(s)... |
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|
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EV::loop; |
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=head1 DESCRIPTION |
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|
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This module coerces the Net::SNMP scheduler to use the EV high performance |
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event loop as underlying event loop, i.e. EV will be used by Net::SNMP for |
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all events. |
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|
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This integrates Net::SNMP into EV: You can make non-blocking Net::SNMP |
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calls and as long as your main program uses the EV event loop, they will |
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run in parallel to anything else that uses EV or AnyEvent. |
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This module does not export anything and does not require you to do |
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anything special apart from loading it. |
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|
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The module is quite short, you can use it as example to implement a |
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similar integration into e.g. Event or other event loops. |
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|
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=cut |
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|
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package Net::SNMP::EV; |
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|
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no warnings; |
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use strict; |
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|
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use Net::SNMP (); |
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use EV (); |
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|
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our $VERSION = '0.12'; |
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|
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our @W; |
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our $DISPATCHER = $Net::SNMP::DISPATCHER; |
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|
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# handle as many snmp events as possible |
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sub drain { |
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while () { |
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$DISPATCHER->one_event; |
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|
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my $next = $DISPATCHER->{_event_queue_h} |
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or return; |
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|
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return $next |
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if !$next->[Net::SNMP::Dispatcher::_ACTIVE] |
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|| $next->[Net::SNMP::Dispatcher::_TIME] > EV::now; |
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} |
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} |
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|
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our $PREPARE = EV::prepare sub { |
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# has any events? |
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if ($DISPATCHER->{_event_queue_h}) { |
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# do some work |
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my $next = drain |
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or return; |
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|
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# register io watchers for all fds and a single timout |
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@W = ( |
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(map { EV::io $_, EV::READ, sub { } } |
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keys %{ $DISPATCHER->{_descriptors} }), |
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|
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(EV::timer +($next->[Net::SNMP::Dispatcher::_ACTIVE] |
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? $next->[Net::SNMP::Dispatcher::_TIME] - EV::now |
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: 0), |
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0, sub { }), |
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); |
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} |
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}; |
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|
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our $CHECK = EV::check sub { |
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# nuke the watchers again (usually their callbacks will not even be called) |
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@W = (); |
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|
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drain |
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if $DISPATCHER->{_event_queue_h}; |
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}; |
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=head1 BUGS |
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|
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Net::SNMP has no (documented or otherwise) API to do what this module |
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does. As such, this module rummages around in the internals of Net::SNMP |
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in a rather inacceptable way, and as thus might be very sensitive to the |
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version of Net::SNMP used (it has been tested with some 5.x versions |
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only, YMMV). |
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=head1 SEE ALSO |
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|
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L<EV>, L<Net::SNMP>, L<AnyEvent>, L<Glib::EV>. |
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=head1 AUTHOR |
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|
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Marc Lehmann <schmorp@schmorp.de> |
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http://home.schmorp.de/ |
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|
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=cut |
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1 |
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