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
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
|
/*
Copyright (C) 2008 Andreas Baumann <abaumann@yahoo.com>
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
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.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "port/sys_internal.h"
#include "port/string.h" /* for memset */
#include "errors.h"
#include "log/log.h"
#include "log/messages.h" /* for i18n */
#include "daemon/signals.h"
#include "port/unused.h"
#define DEFAULT_TEXT_DOMAIN "libwolf"
#include "i18n/gettext.h" /* for i18n */
#include <unistd.h> /* for getpid, pipe, write, read */
#include <errno.h> /* for errno */
#include <sys/types.h> /* for ssize_t */
#include <sys/select.h> /* for FD_XX and select */
const char *wolf_signal_get_short_name( int sig ) {
switch( sig ) {
case SIGHUP: return "SIGHUP";
case SIGINT: return "SIGINT";
case SIGQUIT: return "SIGQUIT";
case SIGILL: return "SIGILL";
case SIGTRAP: return "SIGTRAP";
case SIGABRT: return "SIGABRT";
#if defined( SIGIOT )
#if SIGIOT != SIGABRT
case SIGIOT: return "SIGIOT";
#endif
#endif
#if defined( SIGEMT )
case SIGEMT: return "SIGEMT";
#endif
case SIGBUS: return "SIGBUS";
case SIGFPE: return "SIGFPE";
case SIGKILL: return "SIGKILL";
case SIGUSR1: return "SIGUSR1";
case SIGSEGV: return "SIGSEGV";
case SIGUSR2: return "SIGUSR2";
case SIGPIPE: return "SIGPIPE";
case SIGALRM: return "SIGALRM";
case SIGTERM: return "SIGTERM";
#if defined( SIGSTKFLT )
case SIGSTKFLT: return "SIGSTKFLT";
#endif
#if defined( SIGCLD )
#if SIGCLD != SIGCHLD
/* the SysV version */
case SIGCLD: return "SIGCLD";
#endif
#endif
/* the POSIX version */
case SIGCHLD: return "SIGCHLD";
case SIGCONT: return "SIGCONT";
case SIGSTOP: return "SIGSTOP";
case SIGTSTP: return "SIGTSTP";
case SIGTTIN: return "SIGTTIN";
case SIGTTOU: return "SIGTTOU";
case SIGURG: return "SIGURG";
case SIGXCPU: return "SIGXCPU";
case SIGXFSZ: return "SIGXFSZ";
case SIGVTALRM: return "SIGVTALRM";
case SIGPROF: return "SIGPROF";
#if defined( SIGWINCH )
case SIGWINCH: return "SIGWINCH";
#endif
#if defined( SIGPOLL )
#if SIGPOLL != SIGIO
/* SysV version of SIGIO */
case SIGPOLL: return "SIGPOLL";
#endif
#endif
#if defined( SIGIO )
case SIGIO: return "SIGIO";
#endif
#if defined( SIGPWR )
case SIGPWR: return "SIGPWR";
#endif
#if defined( SIGSYS )
case SIGSYS: return "SIGSYS";
#endif
#if defined( SIGLOST )
case SIGLOST: return "SIGLOST";
#endif
default: return NULL;
}
}
const char *wolf_signal_get_long_name( int sig ) {
/* we don't trust strsignal, needs _GNU_SOURCE,
* naming comes from bits/signum.h on Linux 2.6
*/
switch( sig ) {
case SIGHUP: return _( "Hangup" );
case SIGINT: return _( "Interrupt" );
case SIGQUIT: return _( "Quit" );
case SIGILL: return _( "Illegal instruction" );
case SIGTRAP: return _( "Trace trap" );
case SIGABRT: return _( "Abort" );
#if defined( SIGIOT )
#if SIGIOT != SIGABRT
case SIGIOT: return _( "IOT trap" );
#endif
#endif
#if defined( SIGEMT )
case SIGEMT: return _( "EMT instruction" );
#endif
case SIGBUS: return _( "BUS error" );
case SIGFPE: return _( "Floating-point exception" );
case SIGKILL: return _( "Kill" );
case SIGUSR1: return _( "User-defined signal 1" );
case SIGSEGV: return _( "Segmentation violation" );
case SIGUSR2: return _( "User-defined signal 2" );
case SIGPIPE: return _( "Broken pipe" );
case SIGALRM: return _( "Alarm clock" );
case SIGTERM: return _( "Termination" );
#if defined( SIGSTKFLT )
case SIGSTKFLT: return _( "Stack fault" );
#endif
#if defined( SIGCLD )
#if SIGCLD != SIGCHLD
case SIGCLD: return _( "Child status has changed" );
#endif
#endif
case SIGCHLD: return _( "Child status has changed" );
case SIGCONT: return _( "Continue" );
case SIGSTOP: return _( "Stop" );
case SIGTSTP: return _( "Keyboard stop" );
case SIGTTIN: return _( "Background read from tty" );
case SIGTTOU: return _( "Background write to tty" );
case SIGURG: return _( "Urgent condition on socket" );
case SIGXCPU: return _( "CPU limit exceeded" );
case SIGXFSZ: return _( "File size limit exceeded" );
case SIGVTALRM: return _( "Virtual alarm clock" );
case SIGPROF: return _( "Profiling alarm clock" );
#if defined( SIGWINCH )
case SIGWINCH: return _( "Window size change" );
#endif
#if defined( SIGPOLL )
#if SIGPOLL != SIGIO
case SIGPOLL: return _( "Pollable event occurred" );
#endif
#endif
#if defined( SIGIO )
case SIGIO: return _( "I/O now possible" );
#endif
#if defined( SIGPWR )
case SIGPWR: return _( "Power failure restart" );
#endif
#if defined( SIGSYS )
case SIGSYS: return _( "Bad system call" );
#endif
#if defined( SIGLOST )
case SIGLOST: return _( "Resource lost" );
#endif
default: return NULL;
}
}
static wolf_error_t vsignal_install_ignore( int sig, va_list ap ) {
struct sigaction sa;
char errbuf[1024];
install_ignore_again:
if( sig == 0 ) return WOLF_OK;
memset( &sa, 0, sizeof( struct sigaction ) );
sa.sa_handler = SIG_IGN;
if( sigaction( sig, &sa, NULL ) < 0 ) {
(void)strerror_r( errno, errbuf, 1024 );
wolf_log( WOLF_LOG_CRIT, WOLF_CATEGORY_DAEMON, WOLF_MSG_DAEMON_CANT_INSTALL_IGNORE_SIGNAL,
_( "Can't ignore signal handler for signal '%s' (%s): %s" ),
wolf_signal_get_long_name( sig ),
wolf_signal_get_short_name( sig ),
sig,
errbuf );
return WOLF_ERR_PROGRAMMING;
}
wolf_log( WOLF_LOG_DEBUG, WOLF_CATEGORY_DAEMON, WOLF_MSG_DAEMON_IGNORE_SIGNAL,
_( "Ignoring signal handler for signal '%s' (%s)" ),
wolf_signal_get_long_name( sig ),
wolf_signal_get_short_name( sig ) );
sig = va_arg( ap, int );
if( sig > 0 ) goto install_ignore_again;
return WOLF_OK;
}
static void empty_handler( int sig ) {
WOLF_UNUSED( sig );
}
static wolf_error_t vsignal_install_empty( int sig, va_list ap ) {
struct sigaction sa;
char errbuf[1024];
install_empty_again:
if( sig == 0 ) return WOLF_OK;
memset( &sa, 0, sizeof( struct sigaction ) );
sa.sa_handler = empty_handler;
if( sigaction( sig, &sa, NULL ) < 0 ) {
(void)strerror_r( errno, errbuf, 1024 );
wolf_log( WOLF_LOG_CRIT, WOLF_CATEGORY_DAEMON, WOLF_MSG_DAEMON_CANT_INSTALL_CRITICAL_SIGNAL,
_( "Can't install empty signal handler for signal '%s' (%s): %s" ),
wolf_signal_get_long_name( sig ),
wolf_signal_get_short_name( sig ),
errbuf );
return WOLF_ERR_PROGRAMMING;
}
wolf_log( WOLF_LOG_DEBUG, WOLF_CATEGORY_DAEMON, WOLF_MSG_DAEMON_CRITICAL_SIGNAL,
_( "Installed empty signal handler for signal '%s' (%s)" ),
wolf_signal_get_long_name( sig ),
wolf_signal_get_short_name( sig ) );
sig = va_arg( ap, int );
if( sig > 0 ) goto install_empty_again;
return WOLF_OK;
}
static void fatal_handler( int sig ) {
struct sigaction sa;
/* reset default behaviour of the signal */
memset( &sa, 0, sizeof( struct sigaction ) );
sa.sa_handler = SIG_DFL;
(void)sigaction( sig, &sa, NULL );
/* log what happened */
wolf_log( WOLF_LOG_ALERT, WOLF_CATEGORY_DAEMON, WOLF_MSG_DAEMON_GOT_SIGNAL,
_( "Got signal '%s' (%s)" ),
wolf_signal_get_long_name( sig ),
wolf_signal_get_short_name( sig ) );
/* we are in one thread when we got the signal, now inform
* all other threads too (see Apache mpm_common.c for this
* trick)
*/
kill( getpid( ), sig );
}
wolf_error_t vsignal_install_func( wolf_signal_func_t func, int sig, va_list ap ) {
struct sigaction sa;
char errbuf[1024];
install_func_again:
memset( &sa, 0, sizeof( struct sigaction ) );
sa.sa_handler = func;
sa.sa_flags = SA_RESTART;
if( sigaction( sig, &sa, NULL ) < 0 ) {
(void)strerror_r( errno, errbuf, 1024 );
wolf_log( WOLF_LOG_CRIT, WOLF_CATEGORY_DAEMON, WOLF_MSG_DAEMON_CANT_INSTALL_FUNC_SIGNAL,
_( "Can't install signal handler for signal '%s' (%s): %s" ),
wolf_signal_get_long_name( sig ),
wolf_signal_get_short_name( sig ),
errbuf );
return WOLF_ERR_PROGRAMMING;
}
wolf_log( WOLF_LOG_DEBUG, WOLF_CATEGORY_DAEMON, WOLF_MSG_DAEMON_FUNC_SIGNAL,
_( "Installed signal handler for signal '%s' (%s)" ),
wolf_signal_get_long_name( sig ),
wolf_signal_get_short_name( sig ) );
sig = va_arg( ap, int );
if( sig > 0 ) goto install_func_again;
return WOLF_OK;
}
wolf_error_t wolf_signal_install_func( wolf_signal_func_t func, int sig, ... ) {
va_list ap;
wolf_error_t error;
va_start( ap, sig );
error = vsignal_install_func( func, sig, ap );
va_end( ap );
return error;
}
#define INSTALL_SIGNAL( MODE ) \
wolf_error_t wolf_signal_install_##MODE( int sig, ... ) { \
va_list ap; \
wolf_error_t error; \
va_start( ap, sig ); \
error = vsignal_install_##MODE( sig, ap ); \
va_end( ap ); \
return error; \
}
INSTALL_SIGNAL( ignore )
INSTALL_SIGNAL( empty )
WOLF_SIGNALS_INSTALL_FUNC( fatal, fatal_handler )
|
