| 1 | |
| 2 | #include <signal.h>
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| 3 | #include "subcmd-util.h"
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| 4 | #include "sigchain.h"
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| 5 |
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| 6 | #define SIGCHAIN_MAX_SIGNALS 32
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| 7 |
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| 8 | struct sigchain_signal {
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| 9 | sigchain_fun *old;
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| 10 | int n;
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| 11 | int alloc;
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| 12 | };
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| 13 | static struct sigchain_signal signals[SIGCHAIN_MAX_SIGNALS];
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| 14 |
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| 15 | static void check_signum(int sig)
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| 16 | {
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| 17 | if (sig < 1 || sig >= SIGCHAIN_MAX_SIGNALS)
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| 18 | die("BUG: signal out of range: %d", sig);
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| 19 | }
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| 20 |
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| 21 | static int sigchain_push(int sig, sigchain_fun f)
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| 22 | {
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| 23 | struct sigchain_signal *s = signals + sig;
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| 24 | check_signum(sig);
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| 25 |
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| 26 | ALLOC_GROW(s->old, s->n + 1, s->alloc);
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| 27 | s->old[s->n] = signal(sig, f);
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| 28 | if (s->old[s->n] == SIG_ERR)
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| 29 | return -1;
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| 30 | s->n++;
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| 31 | return 0;
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| 32 | }
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| 33 |
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| 34 | int sigchain_pop(int sig)
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| 35 | {
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| 36 | struct sigchain_signal *s = signals + sig;
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| 37 | check_signum(sig);
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| 38 | if (s->n < 1)
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| 39 | return 0;
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| 40 |
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| 41 | if (signal(sig, s->old[s->n - 1]) == SIG_ERR)
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| 42 | return -1;
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| 43 | s->n--;
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| 44 | return 0;
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| 45 | }
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| 46 |
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| 47 | void sigchain_push_common(sigchain_fun f)
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| 48 | {
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| 49 | sigchain_push(SIGINT, f);
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| 50 | sigchain_push(SIGHUP, f);
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| 51 | sigchain_push(SIGTERM, f);
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| 52 | sigchain_push(SIGQUIT, f);
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| 53 | sigchain_push(SIGPIPE, f);
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| 54 | }
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