1 /* Copyright (C) 1992-2022 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, see
16    <https://www.gnu.org/licenses/>.  */
17 
18 #include <stddef.h>
19 #include <signal.h>
20 #include <errno.h>
21 #include <sigsetops.h>
22 
23 /* If INTERRUPT is nonzero, make signal SIG interrupt system calls
24    (causing them to fail with EINTR); if INTERRUPT is zero, make system
25    calls be restarted after signal SIG.  */
26 int
siginterrupt(int sig,int interrupt)27 siginterrupt (int sig, int interrupt)
28 {
29 #ifdef	SA_RESTART
30   extern sigset_t _sigintr attribute_hidden;	/* Defined in signal.c.  */
31   struct sigaction action;
32 
33   if (__sigaction (sig, (struct sigaction *) NULL, &action) < 0)
34     return -1;
35 
36   if (interrupt)
37     {
38       __sigaddset (&_sigintr, sig);
39       action.sa_flags &= ~SA_RESTART;
40     }
41   else
42     {
43       __sigdelset (&_sigintr, sig);
44       action.sa_flags |= SA_RESTART;
45     }
46 
47   if (__sigaction (sig, &action, (struct sigaction *) NULL) < 0)
48     return -1;
49 
50   return 0;
51 #else
52   __set_errno (ENOSYS);
53   return -1;
54 #endif
55 }
56