blob: a696a54267bc58dea92fa68f9c16b4ca8580ce57 [file] [log] [blame]
lh9ed821d2023-04-07 01:36:19 -07001/* Copyright (C) 1991, 1992, 1996, 1997, 2005 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, write to the Free
16 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
17 02111-1307 USA. */
18
19#include <errno.h>
20#include <signal.h>
21#include <string.h> /* For the real memset prototype. */
22
23
24/* Tolerate non-threads versions of Posix */
25#ifndef SA_ONESHOT
26#define SA_ONESHOT 0
27#endif
28#ifndef SA_NOMASK
29#define SA_NOMASK 0
30#endif
31#ifndef SA_INTERRUPT
32#define SA_INTERRUPT 0
33#endif
34
35/* Set the handler for the signal SIG to HANDLER,
36 returning the old handler, or SIG_ERR on error. */
37__sighandler_t __sysv_signal (int sig, __sighandler_t handler)
38{
39 struct sigaction act, oact;
40
41 /* Check signal extents to protect __sigismember. */
42 if (handler == SIG_ERR || sig < 1 || sig >= NSIG)
43 {
44 __set_errno (EINVAL);
45 return SIG_ERR;
46 }
47
48 act.sa_handler = handler;
49 __sigemptyset (&act.sa_mask);
50 act.sa_flags = (SA_ONESHOT | SA_NOMASK | SA_INTERRUPT) & ~SA_RESTART;
51 /* In Linux (as of 2.6.25), fails only if sig is SIGKILL or SIGSTOP */
52 if (sigaction (sig, &act, &oact) < 0)
53 return SIG_ERR;
54
55 return oact.sa_handler;
56}
57strong_alias(__sysv_signal,sysv_signal)