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
|
/* signal.c
Signal handling routines.
Copyright (C) 1992 Ian Lance Taylor
This file is part of the Taylor UUCP package.
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 2 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, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
The author of the program may be contacted at ian@airs.com or
c/o Cygnus Support, 48 Grove Street, Somerville, MA 02144.
*/
#include "uucp.h"
#include "uudefs.h"
#include "sysdep.h"
#include "system.h"
#include <errno.h>
/* Signal handling routines. When we catch a signal, we want to set
the appropriate elements of afSignal and afLog_signal to TRUE. If
we are on a system which restarts system calls, we may also want to
longjmp out. On a system which does not restart system calls,
these signal handling routines are well-defined by ANSI C. */
#if HAVE_RESTARTABLE_SYSCALLS
volatile sig_atomic_t fSjmp;
volatile jmp_buf sSjmp_buf;
#endif /* HAVE_RESTARTABLE_SYSCALLS */
/* Some systems, such as SunOS, have a SA_INTERRUPT bit that must be
set in the sigaction structure to force system calls to be
interrupted. */
#ifndef SA_INTERRUPT
#define SA_INTERRUPT 0
#endif
/* The SVR3 sigset function can be called just like signal, unless
system calls are restarted which is extremely unlikely; we prevent
this case in sysh.unx. */
#if HAVE_SIGSET && ! HAVE_SIGACTION && ! HAVE_SIGVEC
#define signal sigset
#endif
/* The sigvec structure changed from 4.2BSD to 4.3BSD. These macros
make the 4.3 code backward compatible. */
#ifndef SV_INTERRUPT
#define SV_INTERRUPT 0
#endif
#if ! HAVE_SIGVEC_SV_FLAGS
#define sv_flags sv_onstack
#endif
/* Catch a signal. Reinstall the signal handler if necessary, set the
appropriate variables, and do a longjmp if necessary. */
RETSIGTYPE
ussignal (isig)
int isig;
{
int iindex;
#if ! HAVE_SIGACTION && ! HAVE_SIGVEC && ! HAVE_SIGSET
(void) signal (isig, ussignal);
#endif
switch (isig)
{
default: iindex = INDEXSIG_SIGHUP; break;
#ifdef SIGINT
case SIGINT: iindex = INDEXSIG_SIGINT; break;
#endif
#ifdef SIGQUIT
case SIGQUIT: iindex = INDEXSIG_SIGQUIT; break;
#endif
#ifdef SIGTERM
case SIGTERM: iindex = INDEXSIG_SIGTERM; break;
#endif
#ifdef SIGPIPE
case SIGPIPE: iindex = INDEXSIG_SIGPIPE; break;
#endif
}
afSignal[iindex] = TRUE;
afLog_signal[iindex] = TRUE;
#if HAVE_RESTARTABLE_SYSCALLS
if (fSjmp)
longjmp (sSjmp_buf, 1);
#endif /* HAVE_RESTARTABLE_SYSCALLS */
}
/* Prepare to catch a signal. This is basically the ANSI C routine
signal, but it uses sigaction or sigvec instead if they are
available. If fforce is FALSE, we do not set the signal if it is
currently being ignored. If pfignored is not NULL and fforce is
FALSE, then *pfignored will be set to TRUE if the signal was
previously being ignored (if fforce is TRUE the value returned in
*pfignored is meaningless). If we can't change the signal handler
we give a fatal error. */
void
usset_signal (isig, pfn, fforce, pfignored)
int isig;
RETSIGTYPE (*pfn) P((int));
boolean fforce;
boolean *pfignored;
{
#if HAVE_SIGACTION
struct sigaction s;
if (! fforce)
{
(void) (sigemptyset (&s.sa_mask));
if (sigaction (isig, (struct sigaction *) NULL, &s) != 0)
ulog (LOG_FATAL, "sigaction (%d): %s", isig, strerror (errno));
if (s.sa_handler == SIG_IGN)
{
if (pfignored != NULL)
*pfignored = TRUE;
return;
}
if (pfignored != NULL)
*pfignored = FALSE;
}
s.sa_handler = pfn;
(void) (sigemptyset (&s.sa_mask));
s.sa_flags = SA_INTERRUPT;
if (sigaction (isig, &s, (struct sigaction *) NULL) != 0)
ulog (LOG_FATAL, "sigaction (%d): %s", isig, strerror (errno));
#else /* ! HAVE_SIGACTION */
#if HAVE_SIGVEC
struct sigvec s;
if (! fforce)
{
if (sigvec (isig, (struct sigvec *) NULL, &s) != 0)
ulog (LOG_FATAL, "sigvec (%d): %s", isig, strerror (errno));
if (s.sv_handler == SIG_IGN)
{
if (pfignored != NULL)
*pfignored = TRUE;
return;
}
if (pfignored != NULL)
*pfignored = FALSE;
}
s.sv_handler = pfn;
s.sv_mask = 0;
s.sv_flags = SV_INTERRUPT;
if (sigvec (isig, &s, (struct sigvec *) NULL) != 0)
ulog (LOG_FATAL, "sigvec (%d): %s", isig, strerror (errno));
#else /* ! HAVE_SIGVEC */
if (! fforce)
{
if (signal (isig, SIG_IGN) == SIG_IGN)
{
if (pfignored != NULL)
*pfignored = TRUE;
return;
}
if (pfignored != NULL)
*pfignored = FALSE;
}
(void) signal (isig, pfn);
#endif /* ! HAVE_SIGVEC */
#endif /* ! HAVE_SIGACTION */
}
/* The routine called by the system independent code, which always
uses the same signal handler. */
void
usysdep_signal (isig)
int isig;
{
usset_signal (isig, ussignal, FALSE, (boolean *) NULL);
}
|
