master
1/* $NetBSD: mqueue.h,v 1.17 2015/06/20 14:41:54 martin Exp $ */
2
3/*
4 * Copyright (c) 2007-2009 Mindaugas Rasiukevicius <rmind at NetBSD org>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29#ifndef _SYS_MQUEUE_H_
30#define _SYS_MQUEUE_H_
31
32/* Maximal number of mqueue descriptors, that process could open */
33#define MQ_OPEN_MAX 512
34
35/* Maximal priority of the message */
36#define MQ_PRIO_MAX 32
37
38struct mq_attr {
39 long mq_flags; /* Flags of message queue */
40 long mq_maxmsg; /* Maximum number of messages */
41 long mq_msgsize; /* Maximum size of the message */
42 long mq_curmsgs; /* Count of the queued messages */
43};
44
45/* Internal kernel data */
46#ifdef _KERNEL
47
48#include <sys/condvar.h>
49#include <sys/mutex.h>
50#include <sys/queue.h>
51#include <sys/selinfo.h>
52#include <sys/types.h>
53#include <sys/param.h>
54
55/*
56 * Flags below are used in mq_flags for internal purposes.
57 * This is permitted according to POSIX.
58 */
59
60/* Message queue is unlinked */
61#define MQ_UNLINKED 0x10000000
62/* There are receive-waiters */
63#define MQ_RECEIVE 0x20000000
64
65/* Maximal length of mqueue name */
66#define MQ_NAMELEN (KERNEL_NAME_MAX + 1)
67
68/* Default size of the message */
69#define MQ_DEF_MSGSIZE 1024
70
71/* Size/bits and index of reserved queue */
72#define MQ_PQSIZE 32
73#define MQ_PQRESQ 0
74
75/* Structure of the message queue. */
76typedef struct mqueue {
77 char * mq_name;
78 kmutex_t mq_mtx;
79 kcondvar_t mq_send_cv;
80 kcondvar_t mq_recv_cv;
81 struct mq_attr mq_attrib;
82 /* Notification */
83 struct selinfo mq_rsel;
84 struct selinfo mq_wsel;
85 struct sigevent mq_sig_notify;
86 struct proc * mq_notify_proc;
87 /* Permissions */
88 mode_t mq_mode;
89 uid_t mq_euid;
90 gid_t mq_egid;
91 /* Reference counter, queue array and bitmap */
92 u_int mq_refcnt;
93 TAILQ_HEAD(, mq_msg) mq_head[1 + MQ_PQSIZE];
94 uint32_t mq_bitmap;
95 /* Entry of the global list */
96 LIST_ENTRY(mqueue) mq_list;
97 /* Time stamps */
98 struct timespec mq_atime;
99 struct timespec mq_mtime;
100 struct timespec mq_btime;
101} mqueue_t;
102
103/* Structure of the message. */
104typedef struct mq_msg {
105 TAILQ_ENTRY(mq_msg) msg_queue;
106 size_t msg_len;
107 u_int msg_prio;
108 uint8_t msg_ptr[1];
109} mq_msg_t;
110
111/* Prototypes */
112void mqueue_print_list(void (*pr)(const char *, ...) __printflike(1, 2));
113int mq_send1(mqd_t, const char *, size_t, u_int, struct timespec *);
114int mq_recv1(mqd_t, void *, size_t, u_int *, struct timespec *, ssize_t *);
115int mqueue_get(mqd_t mqd, int fflag, mqueue_t **mqret);
116int mq_handle_open(struct lwp *l, const char *, int, mode_t,
117 struct mq_attr*, register_t *retval);
118
119#endif /* _KERNEL */
120
121#endif /* _SYS_MQUEUE_H_ */