source: rtems/cpukit/posix/src/mqueuerecvsupp.c @ 970e001

4.9
Last change on this file since 970e001 was 970e001, checked in by Joel Sherrill <joel.sherrill@…>, on Aug 21, 2011 at 7:59:13 PM

2011-08-21 Joel Sherrill <joel.sherrilL@…>

PR 1890/cpukit

  • posix/src/mqueuerecvsupp.c: POSIX says msg_prio is allowed to be NULL.
  • Property mode set to 100644
File size: 3.4 KB
Line 
1/*
2 *  NOTE:  The structure of the routines is identical to that of POSIX
3 *         Message_queues to leave the option of having unnamed message
4 *         queues at a future date.  They are currently not part of the
5 *         POSIX standard but unnamed message_queues are.  This is also
6 *         the reason for the apparently unnecessary tracking of
7 *         the process_shared attribute.  [In addition to the fact that
8 *         it would be trivial to add pshared to the mq_attr structure
9 *         and have process private message queues.]
10 *
11 *         This code ignores the O_RDONLY/O_WRONLY/O_RDWR flag at open
12 *         time.
13 *
14 *  COPYRIGHT (c) 1989-2011.
15 *  On-Line Applications Research Corporation (OAR).
16 *
17 *  The license and distribution terms for this file may be
18 *  found in the file LICENSE in this distribution or at
19 *  http://www.rtems.com/license/LICENSE.
20 *
21 *  $Id$
22 */
23
24#if HAVE_CONFIG_H
25#include "config.h"
26#endif
27
28#include <stdarg.h>
29
30#include <pthread.h>
31#include <limits.h>
32#include <errno.h>
33#include <fcntl.h>
34#include <mqueue.h>
35
36#include <rtems/system.h>
37#include <rtems/score/watchdog.h>
38#include <rtems/seterr.h>
39#include <rtems/posix/mqueue.h>
40#include <rtems/posix/time.h>
41
42/*
43 *  _POSIX_Message_queue_Receive_support
44 *
45 *  NOTE: XXX Document how size, priority, length, and the buffer go
46 *        through the layers.
47 */
48
49ssize_t _POSIX_Message_queue_Receive_support(
50  mqd_t               mqdes,
51  char               *msg_ptr,
52  size_t              msg_len,
53  unsigned int       *msg_prio,
54  bool                wait,
55  Watchdog_Interval   timeout
56)
57{
58  POSIX_Message_queue_Control     *the_mq;
59  POSIX_Message_queue_Control_fd  *the_mq_fd;
60  Objects_Locations                location;
61  size_t                           length_out;
62  bool                             do_wait;
63
64  the_mq_fd = _POSIX_Message_queue_Get_fd( mqdes, &location );
65  switch ( location ) {
66
67    case OBJECTS_LOCAL:
68      if ( (the_mq_fd->oflag & O_ACCMODE) == O_WRONLY ) {
69        _Thread_Enable_dispatch();
70        rtems_set_errno_and_return_minus_one( EBADF );
71      }
72
73      the_mq = the_mq_fd->Queue;
74
75      if ( msg_len < the_mq->Message_queue.maximum_message_size ) {
76        _Thread_Enable_dispatch();
77        rtems_set_errno_and_return_minus_one( EMSGSIZE );
78      }
79
80      /*
81       *  Now if something goes wrong, we return a "length" of -1
82       *  to indicate an error.
83       */
84
85      length_out = -1;
86
87      /*
88       *  A timed receive with a bad time will do a poll regardless.
89       */
90      if ( wait )
91        do_wait = (the_mq_fd->oflag & O_NONBLOCK) ? FALSE : TRUE;
92      else
93        do_wait = wait;
94
95      /*
96       *  Now perform the actual message receive
97       */
98      _CORE_message_queue_Seize(
99        &the_mq->Message_queue,
100        mqdes,
101        msg_ptr,
102        &length_out,
103        do_wait,
104        timeout
105      );
106
107      _Thread_Enable_dispatch();
108      if (msg_prio) {
109        *msg_prio = _POSIX_Message_queue_Priority_from_core(
110             _Thread_Executing->Wait.count
111          );
112      }
113
114      if ( !_Thread_Executing->Wait.return_code )
115        return length_out;
116
117      rtems_set_errno_and_return_minus_one(
118        _POSIX_Message_queue_Translate_core_message_queue_return_code(
119          _Thread_Executing->Wait.return_code
120        )
121      );
122
123#if defined(RTEMS_MULTIPROCESSING)
124    case OBJECTS_REMOTE:
125#endif
126    case OBJECTS_ERROR:
127      break;
128  }
129
130  rtems_set_errno_and_return_minus_one( EBADF );
131}
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