usr/src/cmd/scadm/sparc/mpxu/common/smq.h

   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
  33 extern "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 */
  88 typedef uint32_t        smq_msg_t;
  89 typedef 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
 101 int smq_init(smq_t *smq, smq_msg_t *msgbuffer, int depth);
 102 int smq_destroy(smq_t *smq);
 103 int smq_receive(smq_t *smq, smq_msg_t *msg);
 104 int smq_send(smq_t *smq, smq_msg_t *msg);
 105 int smq_pendingmsgs(smq_t *smq, int *num);
 106 int smq_depth(smq_t *smq, int *depth);
 107 int smq_xreceive(smq_t *smq, timestruc_t *timeout, smq_msg_t *msg);
 108
 109 #ifdef  __cplusplus
 110 }
 111 #endif
 112
 113 #endif /* _SMQ_H */