1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License").  You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22/*
23 * Copyright 2002 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27#ifndef _SMQ_H
28#define	_SMQ_H
29
30#pragma ident	"%Z%%M%	%I%	%E% SMI"
31
32#ifdef	__cplusplus
33extern "C" {
34#endif
35
36#include <sys/types.h>
37#include <time.h>
38
39#include "xsem.h"
40
41/* THIS IS CURRENTLY ONLY WRITTEN TO HANDLE A SINGLE PRODUCER, SINGLE */
42/* CONSUMER !!!!!!!!!!!!!!!! */
43
44/* Simple message queue */
45/* This package allows threads to pass simple messages through shared	*/
46/* local memory.  The goal is to keep it simple and somewhat fast	*/
47
48/* smq_init() creates a simple message queue structure.  It returns	*/
49/* 0 on success.  You pass it a descriptor, the location of the buffer	*/
50/* where the messages will be stored, and the size of the buffer	*/
51/* (the number of messages that can be stored).  The memory allocation	*/
52/* of the simple message buffer is the programmers responsibility.	*/
53
54/* smq_destroy() deativates a message queue structure */
55
56/* smq_receive() retrieves a message off of the simple message queue.	*/
57/* The message will be  removed from the queue when this routine	*/
58/* returns.  It suspends the thread until a message is received.	*/
59
60/* smq_send() places a message on the specified simple message queue. */
61/* It returns 0 on success. If the simple message queue is full, */
62/* SMQ_FULL is returned. */
63
64/* smq_pendingmsgs() returns the number of pending messages currently */
65/* on the queue. It returns 0 on success. */
66
67/* smq_depth() returns the depth of the queue. It returns 0 on */
68/* success. */
69
70/* smq_timedreceive() retrieves a message off of the simple message */
71/* queue. The message will be  removed from the queue when this  */
72/* routine returns.  It suspends the thread until a message is  */
73/* received or until 'timeout' has expired. It returns 0 on success */
74/* and SMQ_TIMEOUT if timeout has expired. */
75
76
77#define	SMQ_INVALID		-1
78#define	SMQ_FULL		-2
79#define	SMQ_NOT_IMPLEMENTED	-3
80#define	SMQ_TIMEOUT		-4
81#define	SMQ_ETIME		-5
82#define	SMQ_ERROR		-127
83
84/* Do NOT read or write to these structures directly. They are  */
85/* implementation dependent and may change over time */
86/* Be sure to declare any instantiation of these to be static if */
87/* you are alocating them on the stack */
88typedef uint32_t	smq_msg_t;
89typedef struct
90{
91	int		smq_control;
92	int		smq_depth;	/* maximum message count */
93	int		smq_count;	/* current message count */
94	smq_msg_t	*smq_msgBuffer;
95	xsem_t		smq_msgAvail;
96	smq_msg_t	*smq_head;
97	smq_msg_t	*smq_tail;
98} smq_t;
99
100
101int smq_init(smq_t *smq, smq_msg_t *msgbuffer, int depth);
102int smq_destroy(smq_t *smq);
103int smq_receive(smq_t *smq, smq_msg_t *msg);
104int smq_send(smq_t *smq, smq_msg_t *msg);
105int smq_pendingmsgs(smq_t *smq, int *num);
106int smq_depth(smq_t *smq, int *depth);
107int smq_xreceive(smq_t *smq, timestruc_t *timeout, smq_msg_t *msg);
108
109#ifdef	__cplusplus
110}
111#endif
112
113#endif /* _SMQ_H */
114