mirror of https://gitee.com/openkylin/linux.git
55 lines
1.0 KiB
C
55 lines
1.0 KiB
C
// SPDX-License-Identifier: GPL-2.0
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#include <signal.h>
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#include "subcmd-util.h"
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#include "sigchain.h"
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#define SIGCHAIN_MAX_SIGNALS 32
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struct sigchain_signal {
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sigchain_fun *old;
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int n;
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int alloc;
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};
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static struct sigchain_signal signals[SIGCHAIN_MAX_SIGNALS];
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static void check_signum(int sig)
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{
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if (sig < 1 || sig >= SIGCHAIN_MAX_SIGNALS)
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die("BUG: signal out of range: %d", sig);
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}
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static int sigchain_push(int sig, sigchain_fun f)
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{
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struct sigchain_signal *s = signals + sig;
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check_signum(sig);
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ALLOC_GROW(s->old, s->n + 1, s->alloc);
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s->old[s->n] = signal(sig, f);
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if (s->old[s->n] == SIG_ERR)
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return -1;
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s->n++;
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return 0;
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}
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int sigchain_pop(int sig)
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{
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struct sigchain_signal *s = signals + sig;
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check_signum(sig);
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if (s->n < 1)
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return 0;
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if (signal(sig, s->old[s->n - 1]) == SIG_ERR)
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return -1;
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s->n--;
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return 0;
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}
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void sigchain_push_common(sigchain_fun f)
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{
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sigchain_push(SIGINT, f);
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sigchain_push(SIGHUP, f);
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sigchain_push(SIGTERM, f);
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sigchain_push(SIGQUIT, f);
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sigchain_push(SIGPIPE, f);
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}
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