qemu/include/io/channel-watch.h
Daniel P. Berrange 1c809fa01d io: add helper module for creating watches on FDs
A number of the channel implementations will require the
ability to create watches on file descriptors / sockets.
To avoid duplicating this code in each channel, provide a
helper API for dealing with file descriptor watches.

There are two watch implementations provided. The first
is useful for bi-directional file descriptors such as
sockets, regular files, character devices, etc. The
second works with a pair of unidirectional file descriptors
such as pipes.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2015-12-18 12:18:05 +00:00

73 lines
2.3 KiB
C

/*
* QEMU I/O channels watch helper APIs
*
* Copyright (c) 2015 Red Hat, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*
*/
#ifndef QIO_CHANNEL_WATCH_H__
#define QIO_CHANNEL_WATCH_H__
#include "io/channel.h"
/*
* This module provides helper functions that will be needed by
* the various QIOChannel implementations, for creating watches
* on file descriptors / sockets
*/
/**
* qio_channel_create_fd_watch:
* @ioc: the channel object
* @fd: the file descriptor
* @condition: the I/O condition
*
* Create a new main loop source that is able to
* monitor the file descriptor @fd for the
* I/O conditions in @condition. This is able
* monitor block devices, character devices,
* sockets, pipes but not plain files.
*
* Returns: the new main loop source
*/
GSource *qio_channel_create_fd_watch(QIOChannel *ioc,
int fd,
GIOCondition condition);
/**
* qio_channel_create_fd_pair_watch:
* @ioc: the channel object
* @fdread: the file descriptor for reading
* @fdwrite: the file descriptor for writing
* @condition: the I/O condition
*
* Create a new main loop source that is able to
* monitor the pair of file descriptors @fdread
* and @fdwrite for the I/O conditions in @condition.
* This is intended for monitoring unidirectional
* file descriptors such as pipes, where a pair
* of descriptors is required for bidirectional
* I/O
*
* Returns: the new main loop source
*/
GSource *qio_channel_create_fd_pair_watch(QIOChannel *ioc,
int fdread,
int fdwrite,
GIOCondition condition);
#endif /* QIO_CHANNEL_WATCH_H__ */