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 38 struct 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. */ 76 typedef 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. */ 104 typedef 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 */ 112 void mqueue_print_list(void (*pr)(const char *, ...) __printflike(1, 2)); 113 int mq_send1(mqd_t, const char *, size_t, u_int, struct timespec *); 114 int mq_recv1(mqd_t, void *, size_t, u_int *, struct timespec *, ssize_t *); 115 int mqueue_get(mqd_t mqd, int fflag, mqueue_t **mqret); 116 int 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_ */ 122