/* SPDX-License-Identifier: LGPL-2.1+ WITH Linux-syscall-note */
/* Copyright (C) 2003 Krzysztof Benedyczak & Michal Wronski
This program 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 2.1 of the License, or (at your option) any later version.
It 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 software; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#ifndef _LINUX_MQUEUE_H
#define _LINUX_MQUEUE_H
#include <linux/types.h>
#define MQ_PRIO_MAX 32768
/* per-uid limit of kernel memory used by mqueue, in bytes */
#define MQ_BYTES_MAX 819200
struct mq_attr {
__kernel_long_t mq_flags; /* message queue flags */
__kernel_long_t mq_maxmsg; /* maximum number of messages */
__kernel_long_t mq_msgsize; /* maximum message size */
__kernel_long_t mq_curmsgs; /* number of messages currently queued */
__kernel_long_t __reserved[4]; /* ignored for input, zeroed for output */
};
/*
* SIGEV_THREAD implementation:
* SIGEV_THREAD must be implemented in user space. If SIGEV_THREAD is passed
* to mq_notify, then
* - sigev_signo must be the file descriptor of an AF_NETLINK socket. It's not
* necessary that the socket is bound.
* - sigev_value.sival_ptr must point to a cookie that is NOTIFY_COOKIE_LEN
* bytes long.
* If the notification is triggered, then the cookie is sent to the netlink
* socket. The last byte of the cookie is replaced with the NOTIFY_?? codes:
* NOTIFY_WOKENUP if the notification got triggered, NOTIFY_REMOVED if it was
* removed, either due to a close() on the message queue fd or due to a
* mq_notify() that removed the notification.
*/
#define NOTIFY_NONE 0
#define NOTIFY_WOKENUP 1
#define NOTIFY_REMOVED 2
#define NOTIFY_COOKIE_LEN 32
#endif