LCOM1920-T02G10

/*        $NetBSD: mqueue.h,v 1.17 2015/06/20 14:41:54 martin Exp $        */

/*

 * Copyright (c) 2007-2009 Mindaugas Rasiukevicius <rmind at NetBSD org>

 * All rights reserved.

 * 

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 *

 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND

 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE

 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 * SUCH DAMAGE.

 */

#ifndef _SYS_MQUEUE_H_

#define _SYS_MQUEUE_H_

/* Maximal number of mqueue descriptors, that process could open */

#define        MQ_OPEN_MAX                512

/* Maximal priority of the message */

#define        MQ_PRIO_MAX                32

struct mq_attr {

        long        mq_flags;        /* Flags of message queue */

        long        mq_maxmsg;        /* Maximum number of messages */

        long        mq_msgsize;        /* Maximum size of the message */

        long        mq_curmsgs;        /* Count of the queued messages */

};

/* Internal kernel data */

#ifdef _KERNEL

#include <sys/condvar.h>

#include <sys/mutex.h>

#include <sys/queue.h>

#include <sys/selinfo.h>

#include <sys/types.h>

#include <sys/param.h>

/*

 * Flags below are used in mq_flags for internal purposes.

 * This is permitted according to POSIX.

 */

/* Message queue is unlinked */

#define        MQ_UNLINKED                0x10000000

/* There are receive-waiters */

#define        MQ_RECEIVE                0x20000000

/* Maximal length of mqueue name */

#define        MQ_NAMELEN                (KERNEL_NAME_MAX + 1)

/* Default size of the message */

#define        MQ_DEF_MSGSIZE                1024

/* Size/bits and index of reserved queue */

#define        MQ_PQSIZE                32

#define        MQ_PQRESQ                0

/* Structure of the message queue. */

typedef struct mqueue {

        char *                        mq_name;

        kmutex_t                mq_mtx;

        kcondvar_t                mq_send_cv;

        kcondvar_t                mq_recv_cv;

        struct mq_attr                mq_attrib;

        /* Notification */

        struct selinfo                mq_rsel;

        struct selinfo                mq_wsel;

        struct sigevent                mq_sig_notify;

        struct proc *                mq_notify_proc;

        /* Permissions */

        mode_t                        mq_mode;

        uid_t                        mq_euid;

        gid_t                        mq_egid;

        /* Reference counter, queue array and bitmap */

        u_int                        mq_refcnt;

        TAILQ_HEAD(, mq_msg)        mq_head[1 + MQ_PQSIZE];

        uint32_t                mq_bitmap;

        /* Entry of the global list */

        LIST_ENTRY(mqueue)        mq_list;

        /* Time stamps */

        struct timespec                mq_atime;

        struct timespec                mq_mtime;

        struct timespec                mq_btime;

} mqueue_t;

/* Structure of the message. */

typedef struct mq_msg {

        TAILQ_ENTRY(mq_msg)        msg_queue;

        size_t                        msg_len;

        u_int                        msg_prio;

        uint8_t                        msg_ptr[1];

} mq_msg_t;

/* Prototypes */

void        mqueue_print_list(void (*pr)(const char *, ...) __printflike(1, 2));

int        mq_send1(mqd_t, const char *, size_t, u_int, struct timespec *);

int        mq_recv1(mqd_t, void *, size_t, u_int *, struct timespec *, ssize_t *);

int        mqueue_get(mqd_t mqd, int fflag, mqueue_t **mqret);

int        mq_handle_open(struct lwp *l, const char *, int, mode_t,

            struct mq_attr*, register_t *retval);

#endif        /* _KERNEL */

#endif        /* _SYS_MQUEUE_H_ */