aboutsummaryrefslogtreecommitdiff
path: root/sysdeps/posix/signal.c
blob: ce93116075e30f3598ac9f632f45f75bf481264d (plain)
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
/* Copyright (C) 1991, 1992, 1996 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 Library General Public License as
   published by the Free Software Foundation; either version 2 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
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#include <errno.h>
#include <signal.h>


sigset_t _sigintr;		/* Set by siginterrupt.  */

/* Set the handler for the signal SIG to HANDLER,
   returning the old handler, or SIG_ERR on error.  */
__sighandler_t
signal (sig, handler)
     int sig;
     __sighandler_t handler;
{
  struct sigaction act, oact;

  /* Check signal extents to protect __sigismember.  */
  if (handler == SIG_ERR || sig < 1 || sig >= NSIG)
    {
      __set_errno (EINVAL);
      return SIG_ERR;
    }

  act.sa_handler = handler;
  if (__sigemptyset (&act.sa_mask) < 0)
    return SIG_ERR;
  act.sa_flags = __sigismember (&_sigintr, sig) ? 0 : SA_RESTART;
  if (__sigaction (sig, &act, &oact) < 0)
    return SIG_ERR;

  return oact.sa_handler;
}