1/* Support functionality for using signals.
2 Copyright (C) 2016-2021 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 <https://www.gnu.org/licenses/>. */
18
19#ifndef SUPPORT_SIGNAL_H
20#define SUPPORT_SIGNAL_H
21
22#include <signal.h>
23#include <sys/cdefs.h>
24
25__BEGIN_DECLS
26
27/* The following functions call the corresponding libc functions and
28 terminate the process on error. */
29
30void xraise (int sig);
31sighandler_t xsignal (int sig, sighandler_t handler);
32void xsigaction (int sig, const struct sigaction *newact,
33 struct sigaction *oldact);
34
35/* The following functions call the corresponding libpthread functions
36 and terminate the process on error. */
37
38void xpthread_sigmask (int how, const sigset_t *set, sigset_t *oldset);
39
40/* Allocate and activate an alternate signal stack. This stack will
41 have SIZE + MINSIGSTKSZ bytes of space, rounded up to a whole
42 number of pages. There will be large (at least 1 MiB) inaccessible
43 guard bands on either side of it. The return value is a cookie
44 that can be passed to xfree_sigstack to deactivate and deallocate
45 the stack again. It is not necessary to call sigaltstack after
46 calling this function. Terminates the process on error. */
47void *xalloc_sigstack (size_t size);
48
49/* Deactivate and deallocate a signal stack created by xalloc_sigstack. */
50void xfree_sigstack (void *stack);
51
52/* Extract the actual address and size of the alternate signal stack from
53 the cookie returned by xalloc_sigstack. */
54void xget_sigstack_location (const void *stack, unsigned char **addrp,
55 size_t *sizep);
56
57__END_DECLS
58
59#endif /* SUPPORT_SIGNAL_H */
60