Josh Poimboeuf | 2f4ce5e | 2015-12-15 09:39:38 -0600 | [diff] [blame] | 1 | #include <signal.h> |
| 2 | #include "subcmd-util.h" |
Ingo Molnar | a930d2c | 2009-05-27 09:50:13 +0200 | [diff] [blame] | 3 | #include "sigchain.h" |
Ingo Molnar | a930d2c | 2009-05-27 09:50:13 +0200 | [diff] [blame] | 4 | |
| 5 | #define SIGCHAIN_MAX_SIGNALS 32 |
| 6 | |
| 7 | struct sigchain_signal { |
| 8 | sigchain_fun *old; |
| 9 | int n; |
| 10 | int alloc; |
| 11 | }; |
| 12 | static struct sigchain_signal signals[SIGCHAIN_MAX_SIGNALS]; |
| 13 | |
| 14 | static 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 Melo | a41794c | 2010-05-18 18:29:23 -0300 | [diff] [blame] | 20 | static int sigchain_push(int sig, sigchain_fun f) |
Ingo Molnar | a930d2c | 2009-05-27 09:50:13 +0200 | [diff] [blame] | 21 | { |
| 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 | |
| 33 | int 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 | |
| 46 | void 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 | } |