1 | /* BSD-like signal function. |
2 | Copyright (C) 1991-2017 Free Software Foundation, Inc. |
3 | This file is part of the GNU C Library. |
4 | |
5 | The GNU C Library is free software; you can redistribute it and/or |
6 | modify it under the terms of the GNU Lesser General Public |
7 | License as published by the Free Software Foundation; either |
8 | version 2.1 of the License, or (at your option) any later version. |
9 | |
10 | The GNU C Library is distributed in the hope that it will be useful, |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
13 | Lesser General Public License for more details. |
14 | |
15 | You should have received a copy of the GNU Lesser General Public |
16 | License along with the GNU C Library; if not, see |
17 | <http://www.gnu.org/licenses/>. */ |
18 | |
19 | #include <errno.h> |
20 | #include <signal.h> |
21 | #include <string.h> /* For the real memset prototype. */ |
22 | |
23 | |
24 | sigset_t _sigintr attribute_hidden; /* Set by siginterrupt. */ |
25 | |
26 | /* Set the handler for the signal SIG to HANDLER, |
27 | returning the old handler, or SIG_ERR on error. */ |
28 | __sighandler_t |
29 | __bsd_signal (int sig, __sighandler_t handler) |
30 | { |
31 | struct sigaction act, oact; |
32 | |
33 | /* Check signal extents to protect __sigismember. */ |
34 | if (handler == SIG_ERR || sig < 1 || sig >= NSIG) |
35 | { |
36 | __set_errno (EINVAL); |
37 | return SIG_ERR; |
38 | } |
39 | |
40 | act.sa_handler = handler; |
41 | if (__sigemptyset (&act.sa_mask) < 0 |
42 | || __sigaddset (&act.sa_mask, sig) < 0) |
43 | return SIG_ERR; |
44 | act.sa_flags = __sigismember (&_sigintr, sig) ? 0 : SA_RESTART; |
45 | if (__sigaction (sig, &act, &oact) < 0) |
46 | return SIG_ERR; |
47 | |
48 | return oact.sa_handler; |
49 | } |
50 | weak_alias (__bsd_signal, bsd_signal) |
51 | weak_alias (__bsd_signal, signal) |
52 | weak_alias (__bsd_signal, ssignal) |
53 | |