1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
|
/*
* Copyright (C) 2013 Felix Fietkau <nbd@openwrt.org>
* Copyright (C) 2013 John Crispin <blogic@openwrt.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License version 2.1
* as published by the Free Software Foundation
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <sys/reboot.h>
#include <sys/types.h>
#include <errno.h>
#include <fcntl.h>
#include <unistd.h>
#include "procd.h"
static int crash_kmsg_fd = -1;
static void crash_kmsg(void)
{
static const char msg[] = "<3>procd: Rebooting as procd has crashed\n";
size_t left = sizeof(msg) - 1;
const char *p = msg;
ssize_t rv;
if (crash_kmsg_fd < 0)
return;
while (left > 0) {
rv = write(crash_kmsg_fd, p, left);
if (rv < 0 && errno == EINTR)
continue;
if (rv <= 0)
return;
left -= rv;
p += rv;
}
}
static void do_reboot(void)
{
sync();
sleep(2);
reboot(RB_AUTOBOOT);
while (1)
;
}
static void signal_shutdown(int signal, siginfo_t *siginfo, void *data)
{
int event = 0;
char *msg = NULL;
#ifndef DISABLE_INIT
switch(signal) {
case SIGINT:
case SIGTERM:
event = RB_AUTOBOOT;
msg = "reboot";
break;
case SIGUSR1:
event = RB_HALT_SYSTEM;
msg = "halt";
break;
case SIGUSR2:
case SIGPWR:
event = RB_POWER_OFF;
msg = "poweroff";
break;
}
#endif
DEBUG(1, "Triggering %s\n", msg);
if (event)
procd_shutdown(event);
}
struct sigaction sa_shutdown = {
.sa_sigaction = signal_shutdown,
.sa_flags = SA_SIGINFO
};
static void signal_crash(int signal, siginfo_t *siginfo, void *data)
{
crash_kmsg();
do_reboot();
}
struct sigaction sa_crash = {
.sa_sigaction = signal_crash,
.sa_flags = SA_SIGINFO
};
static void signal_dummy(int signal, siginfo_t *siginfo, void *data)
{
ERROR("Got unexpected signal %d\n", signal);
}
struct sigaction sa_dummy = {
.sa_sigaction = signal_dummy,
.sa_flags = SA_SIGINFO
};
void procd_signal(void)
{
signal(SIGPIPE, SIG_IGN);
if (getpid() != 1)
return;
crash_kmsg_fd = open("/dev/kmsg", O_WRONLY | O_CLOEXEC);
sigaction(SIGTERM, &sa_shutdown, NULL);
sigaction(SIGINT, &sa_shutdown, NULL);
sigaction(SIGUSR1, &sa_shutdown, NULL);
sigaction(SIGUSR2, &sa_shutdown, NULL);
sigaction(SIGPWR, &sa_shutdown, NULL);
sigaction(SIGSEGV, &sa_crash, NULL);
sigaction(SIGBUS, &sa_crash, NULL);
sigaction(SIGHUP, &sa_dummy, NULL);
sigaction(SIGKILL, &sa_dummy, NULL);
sigaction(SIGSTOP, &sa_dummy, NULL);
#ifndef DISABLE_INIT
reboot(RB_DISABLE_CAD);
#endif
}
void procd_signal_reset(void)
{
struct sigaction s = { 0 };
int i;
s.sa_handler = SIG_DFL;
for (i = 1; i < _NSIG; i++)
sigaction(i, &s, NULL);
}
void procd_signal_block(sigset_t *oldset)
{
sigset_t set;
sigemptyset(&set);
sigaddset(&set, SIGTERM);
sigaddset(&set, SIGINT);
sigaddset(&set, SIGUSR1);
sigaddset(&set, SIGUSR2);
sigaddset(&set, SIGPWR);
sigaddset(&set, SIGHUP);
sigprocmask(SIG_BLOCK, &set, oldset);
}
void procd_signal_restore(const sigset_t *oldset)
{
sigprocmask(SIG_SETMASK, oldset, NULL);
}
|
