1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
|
/****************************************************************************
* sched/mq_close.c
*
* Copyright (C) 2007, 2009, 2013 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <mqueue.h>
#include <sched.h>
#include <assert.h>
#include "os_internal.h"
#include "mq_internal.h"
/****************************************************************************
* Definitions
****************************************************************************/
/****************************************************************************
* Private Type Declarations
****************************************************************************/
/****************************************************************************
* Global Variables
****************************************************************************/
/****************************************************************************
* Private Variables
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: mq_desfree
*
* Description:
* Deallocate a message queue descriptor but returning it to the free list
*
* Inputs:
* mqdes - message queue descriptor to free
*
****************************************************************************/
#define mq_desfree(mqdes) sq_addlast((FAR sq_entry_t*)mqdes, &g_desfree)
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: mq_close
*
* Description:
* This function is used to indicate that the calling task is finished
* with the specified message queued mqdes. The mq_close() deallocates
* any system resources allocated by the system for use by this task for
* its message queue.
*
* If the calling task has attached a notification to the message queue
* via this mqdes, this attachment will be removed and the message queue
* is available for another process to attach a notification.
*
* Parameters:
* mqdes - Message queue descriptor.
*
* Return Value:
* 0 (OK) if the message queue is closed successfully,
* otherwise, -1 (ERROR).
*
* Assumptions:
* - The behavior of a task that is blocked on either a mq_send() or
* mq_receive() is undefined when mq_close() is called.
* - The results of using this message queue descriptor after a successful
* return from mq_close() is undefined.
*
****************************************************************************/
int mq_close(mqd_t mqdes)
{
FAR struct tcb_s *rtcb = (FAR struct tcb_s*)g_readytorun.head;
FAR struct task_group_s *group = rtcb->group;
FAR msgq_t *msgq;
irqstate_t saved_state;
int ret = ERROR;
DEBUGASSERT(group);
/* Verify the inputs */
if (mqdes)
{
sched_lock();
/* Remove the message descriptor from the current task's
* list of message descriptors.
*/
sq_rem((FAR sq_entry_t*)mqdes, &group->tg_msgdesq);
/* Find the message queue associated with the message descriptor */
msgq = mqdes->msgq;
/* Check if the calling task has a notification attached to
* the message queue via this mqdes.
*/
#ifndef CONFIG_DISABLE_SIGNALS
if (msgq->ntmqdes == mqdes)
{
msgq->ntpid = INVALID_PROCESS_ID;
msgq->ntsigno = 0;
msgq->ntvalue.sival_int = 0;
msgq->ntmqdes = NULL;
}
#endif
/* Decrement the connection count on the message queue. */
if (msgq->nconnect)
{
msgq->nconnect--;
}
/* If it is no longer connected to any message descriptor and if the
* message queue has already been unlinked, then we can discard the
* message queue.
*/
if (!msgq->nconnect && msgq->unlinked)
{
/* Remove the message queue from the list of all
* message queues
*/
saved_state = irqsave();
(void)sq_rem((FAR sq_entry_t*)msgq, &g_msgqueues);
irqrestore(saved_state);
/* Then deallocate it (and any messages left in it) */
mq_msgqfree(msgq);
}
/* Deallocate the message descriptor */
mq_desfree(mqdes);
sched_unlock();
ret = OK;
}
return ret;
}
|
