asterisk/include/asterisk/alertpipe.h

164 lines
4.2 KiB
C

/*
* Asterisk -- An open source telephony toolkit.
*
* Copyright (C) 2017, Sean Bright
*
* Sean Bright <sean.bright@gmail.com>
*
* See http://www.asterisk.org for more information about
* the Asterisk project. Please do not directly contact
* any of the maintainers of this project for assistance;
* the project provides a web site, mailing lists and IRC
* channels for your use.
*
* This program is free software, distributed under the terms of
* the GNU General Public License Version 2. See the LICENSE file
* at the top of the source tree.
*/
#ifndef ASTERISK_ALERTPIPE_H
#define ASTERISK_ALERTPIPE_H
#include "asterisk/utils.h"
typedef enum {
AST_ALERT_READ_SUCCESS = 0,
AST_ALERT_NOT_READABLE,
AST_ALERT_READ_FAIL,
AST_ALERT_READ_FATAL,
} ast_alert_status_t;
/*!
* \brief Initialize an alert pipe
* \since 13.16.0
*
* \param alert_pipe a two-element array to hold the alert pipe's file descriptors
*
* \retval non-zero if a failure occurred.
* \retval zero otherwise.
*/
int ast_alertpipe_init(int alert_pipe[2]);
/*!
* \brief Close an alert pipe
* \since 13.16.0
*
* \param alert_pipe a two-element containing the alert pipe's file descriptors
*/
void ast_alertpipe_close(int alert_pipe[2]);
/*!
* \brief Read an event from an alert pipe
* \since 13.16.0
*
* \param alert_pipe a two-element array containing the alert pipe's file descriptors
*
* \retval AST_ALERT_READ_SUCCESS on success
* \retval AST_ALERT_NOT_READABLE if the alert pipe is not readable
* \retval AST_ALERT_READ_FATAL if the alert pipe's file descriptors are in
* blocking mode, or a read error occurs.
*/
ast_alert_status_t ast_alertpipe_read(int alert_pipe[2]);
/*!
* \brief Write an event to an alert pipe
* \since 13.16.0
*
* \param alert_pipe a two-element array containing the alert pipe's file descriptors
*
* \retval 0 Success
* \retval 1 Failure
*/
ssize_t ast_alertpipe_write(int alert_pipe[2]);
/*!
* \brief Consume all alerts written to the alert pipe
* \since 13.16.0
*
* \param alert_pipe a two-element array containing the alert pipe's file descriptors
*
* \retval AST_ALERT_READ_SUCCESS on success
* \retval AST_ALERT_NOT_READABLE if the alert pipe is not readable
* \retval AST_ALERT_READ_FATAL if the alert pipe's file descriptors are in
* blocking mode, or a read error occurs.
*/
ast_alert_status_t ast_alertpipe_flush(int alert_pipe[2]);
/*!
* \brief Sets the alert pipe file descriptors to default values
* \since 13.16.0
*
* \param alert_pipe a two-element array containing the alert pipe's file descriptors
*/
AST_INLINE_API(
void ast_alertpipe_clear(int alert_pipe[2]),
{
alert_pipe[0] = alert_pipe[1] = -1;
}
)
/*!
* \brief Determine if the alert pipe is readable
* \since 13.16.0
*
* \param alert_pipe a two-element array containing the alert pipe's file descriptors
*
* \retval non-zero if the alert pipe is readable.
* \retval zero otherwise.
*/
AST_INLINE_API(
int attribute_pure ast_alertpipe_readable(int alert_pipe[2]),
{
return alert_pipe[0] > -1;
}
)
/*!
* \brief Determine if the alert pipe is writable
* \since 13.16.0
*
* \param alert_pipe a two-element array containing the alert pipe's file descriptors
*
* \retval non-zero if the alert pipe is writable.
* \retval zero otherwise.
*/
AST_INLINE_API(
int attribute_pure ast_alertpipe_writable(int alert_pipe[2]),
{
return alert_pipe[1] > -1;
}
)
/*!
* \brief Get the alert pipe's read file descriptor
* \since 13.16.0
*
* \param alert_pipe a two-element array containing the alert pipe's file descriptors
*
* \retval -1 if the file descriptor is not initialized.
* \retval non-negative otherwise.
*/
AST_INLINE_API(
int attribute_pure ast_alertpipe_readfd(int alert_pipe[2]),
{
return alert_pipe[0];
}
)
/*!
* \brief Swap the file descriptors from two alert pipes
* \since 13.16.0
*
* \param alert_pipe_1 a two-element array containing an alert pipe's file descriptors
* \param alert_pipe_2 a two-element array containing an alert pipe's file descriptors
*/
AST_INLINE_API(
void ast_alertpipe_swap(int alert_pipe_1[2], int alert_pipe_2[2]),
{
SWAP(alert_pipe_1[0], alert_pipe_2[0]);
SWAP(alert_pipe_1[1], alert_pipe_2[1]);
}
)
#endif /* ASTERISK_ALERTPIPE_H */