OpenCores
URL https://opencores.org/ocsvn/openrisc/openrisc/trunk

Subversion Repositories openrisc

[/] [openrisc/] [trunk/] [rtos/] [rtems/] [c/] [src/] [exec/] [rtems/] [src/] [semobtain.c] - Blame information for rev 846

Go to most recent revision | Details | Compare with Previous | View Log

Line No. Rev Author Line
1 30 unneback
/*
2
 *  Semaphore Manager
3
 *
4
 *  DESCRIPTION:
5
 *
6
 *  This package is the implementation of the Semaphore Manager.
7
 *  This manager utilizes standard Dijkstra counting semaphores to provide
8
 *  synchronization and mutual exclusion capabilities.
9
 *
10
 *  Directives provided are:
11
 *
12
 *     + create a semaphore
13
 *     + get an ID of a semaphore
14
 *     + delete a semaphore
15
 *     + acquire a semaphore
16
 *     + release a semaphore
17
 *
18
 *  COPYRIGHT (c) 1989-1999.
19
 *  On-Line Applications Research Corporation (OAR).
20
 *
21
 *  The license and distribution terms for this file may be
22
 *  found in the file LICENSE in this distribution or at
23
 *  http://www.OARcorp.com/rtems/license.html.
24
 *
25
 *  $Id: semobtain.c,v 1.2 2001-09-27 11:59:19 chris Exp $
26
 */
27
 
28
#include <rtems/system.h>
29
#include <rtems/rtems/status.h>
30
#include <rtems/rtems/support.h>
31
#include <rtems/rtems/attr.h>
32
#include <rtems/score/isr.h>
33
#include <rtems/score/object.h>
34
#include <rtems/rtems/options.h>
35
#include <rtems/rtems/sem.h>
36
#include <rtems/score/coremutex.h>
37
#include <rtems/score/coresem.h>
38
#include <rtems/score/states.h>
39
#include <rtems/score/thread.h>
40
#include <rtems/score/threadq.h>
41
#if defined(RTEMS_MULTIPROCESSING)
42
#include <rtems/score/mpci.h>
43
#endif
44
#include <rtems/score/sysstate.h>
45
 
46
#include <rtems/score/interr.h>
47
 
48
/*PAGE
49
 *
50
 *  rtems_semaphore_obtain
51
 *
52
 *  This directive allows a thread to acquire a semaphore.
53
 *
54
 *  Input parameters:
55
 *    id         - semaphore id
56
 *    option_set - wait option
57
 *    timeout    - number of ticks to wait (0 means wait forever)
58
 *
59
 *  Output parameters:
60
 *    RTEMS_SUCCESSFUL - if successful
61
 *    error code        - if unsuccessful
62
 */
63
 
64
rtems_status_code rtems_semaphore_obtain(
65
  Objects_Id      id,
66
  unsigned32      option_set,
67
  rtems_interval  timeout
68
)
69
{
70
  register Semaphore_Control *the_semaphore;
71
  Objects_Locations           location;
72
  boolean                     wait;
73
 
74
  the_semaphore = _Semaphore_Get( id, &location );
75
  switch ( location ) {
76
    case OBJECTS_REMOTE:
77
#if defined(RTEMS_MULTIPROCESSING)
78
      return _Semaphore_MP_Send_request_packet(
79
          SEMAPHORE_MP_OBTAIN_REQUEST,
80
          id,
81
          option_set,
82
          timeout
83
      );
84
#endif
85
 
86
    case OBJECTS_ERROR:
87
      return RTEMS_INVALID_ID;
88
 
89
    case OBJECTS_LOCAL:
90
      if ( _Options_Is_no_wait( option_set ) )
91
        wait = FALSE;
92
      else
93
        wait = TRUE;
94
 
95
      if ( !_Attributes_Is_counting_semaphore(the_semaphore->attribute_set) ) {
96
        _CORE_mutex_Seize(
97
          &the_semaphore->Core_control.mutex,
98
          id,
99
          wait,
100
          timeout
101
        );
102
        _Thread_Enable_dispatch();
103
        return _Semaphore_Translate_core_mutex_return_code(
104
                  _Thread_Executing->Wait.return_code );
105
      } else {
106
        _CORE_semaphore_Seize(
107
          &the_semaphore->Core_control.semaphore,
108
          id,
109
          wait,
110
          timeout
111
        );
112
        _Thread_Enable_dispatch();
113
        return _Semaphore_Translate_core_semaphore_return_code(
114
                  _Thread_Executing->Wait.return_code );
115
      }
116
  }
117
 
118
  return RTEMS_INTERNAL_ERROR;   /* unreached - only to remove warnings */
119
}

powered by: WebSVN 2.1.0

© copyright 1999-2024 OpenCores.org, equivalent to Oliscience, all rights reserved. OpenCores®, registered trademark.