1/*
2  FUSE: Filesystem in Userspace
3  Copyright (C) 2001-2007  Miklos Szeredi <miklos@szeredi.hu>
4
5  This program can be distributed under the terms of the GNU LGPLv2.
6  See the file COPYING.LIB
7*/
8
9#include "fuse_api.h"
10#include "fuse_lowlevel.h"
11
12#include <stdio.h>
13#include <string.h>
14#include <signal.h>
15
16static struct fuse_session *fuse_instance;
17
18static void exit_handler(int sig)
19{
20	(void) sig;
21	if (fuse_instance)
22		fuse_session_exit(fuse_instance);
23}
24
25static int set_one_signal_handler(int sig, void (*handler)(int), int remove)
26{
27	struct sigaction sa;
28	struct sigaction old_sa;
29
30	memset(&sa, 0, sizeof(struct sigaction));
31	sa.sa_handler = remove ? SIG_DFL : handler;
32	sigemptyset(&(sa.sa_mask));
33	sa.sa_flags = 0;
34
35	if (sigaction(sig, NULL, &old_sa) == -1) {
36		perror("fuse: cannot get old signal handler");
37		return -1;
38	}
39
40	if (old_sa.sa_handler == (remove ? handler : SIG_DFL) &&
41	    sigaction(sig, &sa, NULL) == -1) {
42		perror("fuse: cannot set signal handler");
43		return -1;
44	}
45	return 0;
46}
47
48int fuse_set_signal_handlers(struct fuse_session *se)
49{
50	if (set_one_signal_handler(SIGHUP, exit_handler, 0) == -1 ||
51	    set_one_signal_handler(SIGINT, exit_handler, 0) == -1 ||
52	    set_one_signal_handler(SIGTERM, exit_handler, 0) == -1 ||
53	    set_one_signal_handler(SIGPIPE, SIG_IGN, 0) == -1)
54		return -1;
55
56	fuse_instance = se;
57	return 0;
58}
59
60void fuse_remove_signal_handlers(struct fuse_session *se)
61{
62	if (fuse_instance != se)
63		fprintf(stderr,
64			"fuse: fuse_remove_signal_handlers: unknown session\n");
65	else
66		fuse_instance = NULL;
67
68	set_one_signal_handler(SIGHUP, exit_handler, 1);
69	set_one_signal_handler(SIGINT, exit_handler, 1);
70	set_one_signal_handler(SIGTERM, exit_handler, 1);
71	set_one_signal_handler(SIGPIPE, SIG_IGN, 1);
72}
73
74