NAME¶
Sys::Virt::Event - An event loop contract
DESCRIPTION¶
The "Sys::Virt::Event" module represents the contract for integrating
libvirt with an event loop. This package is abstract and intended to be
subclassed to provide an actual implementation.
METHODS¶
- register_default()
- Register the default libvirt event loop implementation
- run_default()
- Run a single iteration of the default event loop
implementation
- register($impl)
- Register an event loop implementation. The implementation
should be a instance of a sub-class of the "Sys::Virt::Event"
package.
- $self->_run_handle_callback($watch, $fd, $events, $cb,
$opaque)
- A helper method for executing a callback in response to one
of more $events on the file handle $fd. The $watch number is the unique
idenifier associated with the file descriptor. The $cb and $opaque
parameters are the callback and data registered for the handle.
- $self->_run_timeout_callback($timer, $cb, $opaque)
- A helper method for executing a callback in response to the
expiry of a timeout identified by $timer. The $cb and $opaque parameters
are the callback and data registered for the timeout.
- $self->_free_callback_opaque($ff, $opaque)
- A helper method for freeing the data associated with a
callback. The $ff and $opaque parameters are the callback and data
registered for the handle/timeout.
- my $watch = Sys::Virt::Event::add_handle($fd, $events,
$coderef)
- Adds a watch on the file descriptor $fd for the events
$events which is a mask of the FILE HANDLE EVENTS constants listed later.
The $coderef parameter is a subroutine to invoke when an event is
triggered. The subroutine will be passed three parameters, the watch
identifier, the file descriptor and the event mask. This method returns
the watch identifier which can be used to update or remove the watch
- Sys::Virt::Event::update_handle($watch, $events)
- Update the event mask for the file descriptor watch $watch
to use the events $events.
- Sys::Virt::Event::remove_handle($watch)
- Remove the event mask for the file descriptor watch
$watch.
- my $watch = Sys::Virt::Event::add_timeout($frequency,
$coderef)
- Adds a timeout to trigger with $frequency milliseconds
interval. The $coderef parameter is a subroutine to invoke when an event
is triggered. The subroutine will be passed one parameter, the timer
identifier. This method returns the watch identifier which can be used to
update or remove the watch
- Sys::Virt::Event::update_timeout($timer, $frequency)
- Update the timeout $timer to have the frequency $frequency
milliseconds.
- Sys::Virt::Event::remove_timeout($timer)
- Remove the timeout $timer
CONSTANTS¶
FILE HANDLE EVENTS¶
When integrating with an event loop the following constants define the file
descriptor events
- Sys::Virt::Event::HANDLE_READABLE
- The file descriptor has data available for read without
blocking
- Sys::Virt::Event::HANDLE_WRITABLE
- The file descriptor has ability to write data without
blocking
- Sys::Virt::Event::HANDLE_ERROR
- An error occurred on the file descriptor
- Sys::Virt::Event::HANDLE_HANGUP
- The remote end of the file descriptor closed
AUTHORS¶
Daniel P. Berrange <berrange@redhat.com>
COPYRIGHT¶
Copyright (C) 2006-2009 Red Hat Copyright (C) 2006-2009 Daniel P. Berrange
LICENSE¶
This program is free software; you can redistribute it and/or modify it under
the terms of either the GNU General Public License as published by the Free
Software Foundation (either version 2 of the License, or at your option any
later version), or, the Artistic License, as specified in the Perl README
file.
SEE ALSO¶
Sys::Virt, "
http://libvirt.org"