summaryrefslogtreecommitdiff
path: root/nuttx/sched/exit.c
blob: 2f287009b137d657a7a33ef9e9cead94a40b4194 (plain) (blame)
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
/****************************************************************************
 * sched/exit.c
 *
 *   Copyright (C) 2007, 2008, 2011 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
 *
 * 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 <stdlib.h>
#include <unistd.h>
#include <debug.h>
#include <errno.h>
#include <nuttx/fs.h>
#include "os_internal.h"

/****************************************************************************
 * Definitions
 ****************************************************************************/

/****************************************************************************
 * Private Type Declarations
 ****************************************************************************/

/****************************************************************************
 * Global Variables
 ****************************************************************************/

/****************************************************************************
 * Private Variables
 ****************************************************************************/

/****************************************************************************
 * Private Function Prototypes
 ****************************************************************************/

/****************************************************************************
 * Private Functionss
 ****************************************************************************/

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/****************************************************************************
 * Function: exit
 *
 * Description:
 *   The  exit()  function  causes normal process termination
 *   and the value of status & 0377 is returned to the parent.
 *
 *   All functions registered with atexit() and on_exit() are
 *   called, in the reverse order  of  their  registration.
 *
 *   All open streams are flushed and closed.  Files created
 *   by tmpfile() are  removed.
 *
 ****************************************************************************/

void exit(int status)
{
  _TCB *tcb = (_TCB*)g_readytorun.head;

  /* Only the lower 8 bits of the exit status are used */

  status &= 0xff;

  /* Flush all streams (File descriptors will be closed when
   * the TCB is deallocated.
   */

#if CONFIG_NFILE_STREAMS > 0
  (void)lib_flushall(tcb->streams);
#endif

  /* Wakeup any tasks waiting for this task to exit */

#ifdef CONFIG_SCHED_WAITPID /* Experimental */
  while (tcb->exitsem.semcount < 0)
    {
      /* "If more than one thread is suspended in waitpid() awaiting
       *  termination of the same process, exactly one thread will return
       *  the process status at the time of the target process termination." 
       *  Hmmm.. what do we return to the others?
       */

      if (tcb->stat_loc)
        {
          *tcb->stat_loc = status << 8;
           tcb->stat_loc = NULL;
        }

      /* Wake up the thread */

      sem_post(&tcb->exitsem);
    }
#endif

  /* If an exit function was registered, call it now. */

#ifdef CONFIG_SCHED_ATEXT
  if (tcb->exitfunc)
    {
      (*tcb->exitfunc)();
    }
#endif

  /* Then "really" exit */

  _exit(status);
}