blob: 3537c348a18ef0a9662fa8b6a6385209866fd2de [file] [log] [blame]
Josh Poimboeuf2f4ce5e2015-12-15 09:39:38 -06001#include <signal.h>
2#include "subcmd-util.h"
Ingo Molnara930d2c2009-05-27 09:50:13 +02003#include "sigchain.h"
Ingo Molnara930d2c2009-05-27 09:50:13 +02004
5#define SIGCHAIN_MAX_SIGNALS 32
6
7struct sigchain_signal {
8 sigchain_fun *old;
9 int n;
10 int alloc;
11};
12static struct sigchain_signal signals[SIGCHAIN_MAX_SIGNALS];
13
14static void check_signum(int sig)
15{
16 if (sig < 1 || sig >= SIGCHAIN_MAX_SIGNALS)
17 die("BUG: signal out of range: %d", sig);
18}
19
Arnaldo Carvalho de Meloa41794c2010-05-18 18:29:23 -030020static int sigchain_push(int sig, sigchain_fun f)
Ingo Molnara930d2c2009-05-27 09:50:13 +020021{
22 struct sigchain_signal *s = signals + sig;
23 check_signum(sig);
24
25 ALLOC_GROW(s->old, s->n + 1, s->alloc);
26 s->old[s->n] = signal(sig, f);
27 if (s->old[s->n] == SIG_ERR)
28 return -1;
29 s->n++;
30 return 0;
31}
32
33int sigchain_pop(int sig)
34{
35 struct sigchain_signal *s = signals + sig;
36 check_signum(sig);
37 if (s->n < 1)
38 return 0;
39
40 if (signal(sig, s->old[s->n - 1]) == SIG_ERR)
41 return -1;
42 s->n--;
43 return 0;
44}
45
46void sigchain_push_common(sigchain_fun f)
47{
48 sigchain_push(SIGINT, f);
49 sigchain_push(SIGHUP, f);
50 sigchain_push(SIGTERM, f);
51 sigchain_push(SIGQUIT, f);
52 sigchain_push(SIGPIPE, f);
53}