usr/src/cmd/isns/isnsd/msgq.c

   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 (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21
  22 /*
  23  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 #include <stdio.h>
  28 #include <stdlib.h>
  29 #include <unistd.h>
  30 #include <pthread.h>
  31 #include <synch.h>
  32
  33 #include "isns_server.h"
  34 #include "isns_msgq.h"
  35 #include "isns_cache.h"
  36 #include "isns_obj.h"
  37 #include "isns_log.h"
  38
  39 msg_queue_t *
  40 queue_calloc(
  41 )
  42 {
  43         msg_queue_t *q;
  44
  45         q = (msg_queue_t *)calloc(1, sizeof (msg_queue_t));
  46
  47         if (q) {
  48                 if (sema_init(&q->q_sema, 0, USYNC_THREAD, NULL) ||
  49                     pthread_mutex_init(&q->q_mutex, NULL)) {
  50                         free(q);
  51                         q = NULL;
  52                 }
  53         }
  54
  55         return (q);
  56 }
  57
  58 int
  59 queue_msg_set(
  60         msg_queue_t *q,
  61         msg_id_t id,
  62         void *data
  63 )
  64 {
  65         msg_text_t *msg;
  66
  67         msg = (msg_text_t *)calloc(1, sizeof (msg_text_t));
  68
  69         if (!msg) {
  70                 return (1);
  71         }
  72
  73         msg->id = id;
  74         msg->data = data;
  75
  76         (void) pthread_mutex_lock(&q->q_mutex);
  77
  78         if (q->q_head == NULL) {
  79                 ASSERT(!q->q_tail);
  80                 q->q_head = msg;
  81                 q->q_tail = msg;
  82         } else {
  83                 ASSERT(q->q_tail);
  84                 q->q_tail->next = msg;
  85                 msg->prev = q->q_tail;
  86                 q->q_tail = msg;
  87         }
  88
  89         (void) pthread_mutex_unlock(&q->q_mutex);
  90
  91         (void) sema_post(&q->q_sema);
  92
  93         return (0);
  94 }
  95
  96 msg_text_t *
  97 queue_msg_get(
  98         msg_queue_t *q
  99 )
 100 {
 101         msg_text_t *msg;
 102
 103         while (sema_wait(&q->q_sema)) {
 104                 (void) sleep(1);
 105         }
 106
 107         (void) pthread_mutex_lock(&q->q_mutex);
 108
 109         msg = q->q_head;
 110         ASSERT(msg);
 111         q->q_head = msg->next;
 112         if (q->q_head == NULL) {
 113                 q->q_tail = NULL;
 114         }
 115
 116         (void) pthread_mutex_unlock(&q->q_mutex);
 117
 118         return (msg);
 119 }
 120
 121 void
 122 queue_msg_free(
 123         msg_text_t *msg
 124 )
 125 {
 126         free(msg);
 127 }