File: sigsuspend.c

package info (click to toggle)
glibc 2.28-10
  • links: PTS, VCS
  • area: main
  • in suites: bullseye, buster, buster-proposed-updates, experimental, sid
  • size: 272,168 kB
  • sloc: ansic: 1,008,602; asm: 259,607; makefile: 11,271; sh: 10,477; python: 6,910; cpp: 4,992; perl: 2,258; awk: 2,005; yacc: 290; pascal: 182; sed: 73
file content (83 lines) | stat: -rw-r--r-- 2,686 bytes parent folder | download | duplicates (4)
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
/* Copyright (C) 1991-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, see
   <http://www.gnu.org/licenses/>.  */

#include <errno.h>
#include <hurd.h>
#include <hurd/signal.h>
#include <hurd/msg.h>

/* Change the set of blocked signals to SET,
   wait until a signal arrives, and restore the set of blocked signals.  */
int
__sigsuspend (const sigset_t *set)
{
  struct hurd_sigstate *ss;
  sigset_t newmask, oldmask, pending;
  mach_port_t wait;
  mach_msg_header_t msg;

  if (set != NULL)
    /* Crash before locking.  */
    newmask = *set;

  /* Get a fresh port we will wait on.  */
  wait = __mach_reply_port ();

  ss = _hurd_self_sigstate ();

  _hurd_sigstate_lock (ss);

  oldmask = ss->blocked;
  if (set != NULL)
    /* Change to the new blocked signal mask.  */
    ss->blocked = newmask & ~_SIG_CANT_MASK;

  /* Notice if any pending signals just became unblocked.  */
  pending = _hurd_sigstate_pending (ss) & ~ss->blocked;

  /* Tell the signal thread to message us when a signal arrives.  */
  ss->suspended = wait;
  _hurd_sigstate_unlock (ss);

  if (pending)
    /* Tell the signal thread to check for pending signals.  */
    __msg_sig_post (_hurd_msgport, 0, 0, __mach_task_self ());

  /* Wait for the signal thread's message.  */
  __mach_msg (&msg, MACH_RCV_MSG, 0, sizeof (msg), wait,
	      MACH_MSG_TIMEOUT_NONE, MACH_PORT_NULL);
  __mach_port_destroy (__mach_task_self (), wait);

  /* Restore the old mask and check for pending signals again.  */
  _hurd_sigstate_lock (ss);
  ss->blocked = oldmask;
  pending = _hurd_sigstate_pending(ss) & ~ss->blocked;
  _hurd_sigstate_unlock (ss);

  if (pending)
    /* Tell the signal thread to check for pending signals.  */
    __msg_sig_post (_hurd_msgport, 0, 0, __mach_task_self ());

  /* We've been interrupted!  And a good thing, too.
     Otherwise we'd never return.
     That's right; this function always returns an error.  */
  errno = EINTR;
  return -1;
}
libc_hidden_def (__sigsuspend)
weak_alias (__sigsuspend, sigsuspend)