struct sigaction prev_sa;

void forwardSignal(int signo, siginfo_t *info, void *context) {
	// One of sa_sigaction and/or sa_handler
	if ((prev_sa.sa_flags&SA_SIGINFO) != 0) {
		prev_sa.sa_sigaction(signo, info, context);
		return;
	}
	if (prev_sa.sa_handler != SIG_IGN && prev_sa.sa_handler != SIG_DFL) {
		prev_sa.sa_handler(signo);
		return;
	}

	fprintf(stderr, "No Go handler to forward to!\n");
	abort();
}

	sa.sa_flags = _SA_SIGINFO | _SA_ONSTACK | _SA_RESTART
	sa.sa_mask = sigset_all
	if fn == abi.FuncPCABIInternal(sighandler) { // abi.FuncPCABIInternal(sighandler) matches the callers in signal_unix.go
		if iscgo {
			fn = abi.FuncPCABI0(cgoSigtramp)
		} else {
			fn = abi.FuncPCABI0(sigtramp)
		}
	}
	sa.sa_handler = fn
	sigaction(i, &sa, nil)

    fprintf(stderr, "Warning: pause should be the first process\n");

  if (sigaction(SIGINT, &(struct sigaction){.sa_handler = sigdown}, NULL) < 0)
    return 1;
  if (sigaction(SIGTERM, &(struct sigaction){.sa_handler = sigdown}, NULL) < 0)
    return 2;
  if (sigaction(SIGCHLD, &(struct sigaction){.sa_handler = sigreap,
                                             .sa_flags = SA_NOCLDSTOP},
                NULL) < 0)
    return 3;

	memset(&act, 0, sizeof act);
	memset(&oldact, 0, sizeof oldact);

	if (goact) {
		if (goact->flags & SA_SIGINFO) {
			act.sa_sigaction = (void(*)(int, siginfo_t*, void*))(goact->handler);
		} else {
			act.sa_handler = (void(*)(int))(goact->handler);
		}
		sigemptyset(&act.sa_mask);
		for (i = 0; i < 8 * sizeof(goact->mask); i++) {
			if (goact->mask.__bits[i/32] & ((uint32_t)(1)<<(i&31))) {
				sigaddset(&act.sa_mask, i+1);
			}

	var sa sigactiont
	sa.sa_flags = _SA_SIGINFO | _SA_ONSTACK | _SA_RESTART
	sa.sa_mask = sigset_all
	if fn == abi.FuncPCABIInternal(sighandler) { // abi.FuncPCABIInternal(sighandler) matches the callers in signal_unix.go
		fn = abi.FuncPCABI0(sigtramp)
	}
	sa.sa_handler = fn
	sigaction(i, &sa, nil)

	memset(&act, 0, sizeof act);
	memset(&oldact, 0, sizeof oldact);

	if (goact) {
		if (goact->flags & SA_SIGINFO) {
			act.sa_sigaction = (void(*)(int, siginfo_t*, void*))(goact->handler);
		} else {
			act.sa_handler = (void(*)(int))(goact->handler);
		}
		sigemptyset(&act.sa_mask);
		for (i = 0; i < 8 * sizeof(goact->mask); i++) {
			if (goact->mask & ((uint64_t)(1)<<i)) {
				sigaddset(&act.sa_mask, (int)(i+1));
			}
		}

#include <asm/siginfo.h>
#include <linux/time.h>

struct xsiginfo {
	int si_signo;
	int si_errno;
	int si_code;
	char _sifields[4];
};

#undef sa_handler
#undef sa_flags
#undef sa_restorer
#undef sa_mask

struct xsigaction {
	void (*sa_handler)(void);
	unsigned long sa_flags;
	void (*sa_restorer)(void);
	unsigned int sa_mask;		// mask last for extensibility
};
*/
import "C"

const (

#include <string.h>

static void abrthandler(int signum) {
	if (signum == SIGABRT) {
		exit(0);  // success
	}
}

void registerAbortHandler() {
	struct sigaction act;
	memset(&act, 0, sizeof act);
	act.sa_handler = abrthandler;
	sigaction(SIGABRT, &act, NULL);
}

static void __attribute__ ((constructor)) sigsetup(void) {
	if (getenv("CGOCATCHPANIC_EARLY_HANDLER") == NULL)
		return;
	registerAbortHandler();
}
*/

static void raise_usr2(int signo) {
	raise(SIGUSR2);
}

static void register_handler(int signo) {
	struct sigaction sa;
	memset(&sa, 0, sizeof(sa));
	sigemptyset(&sa.sa_mask);
	sa.sa_flags = SA_ONSTACK;
	sa.sa_handler = raise_usr2;

	if (sigaction(SIGUSR1, &sa, NULL) != 0) {
		perror("failed to register SIGUSR1 handler");
		exit(EXIT_FAILURE);
	}
}
*/
import "C"

func main() {
	ch := make(chan os.Signal, 1)

	sa.sa_flags = SA_ONSTACK | SA_SIGINFO;
	memset(&osa, 0, sizeof osa);
	sigemptyset(&osa.sa_mask);
	if (sigaction(SIGSEGV, &sa, &osa) < 0) {
		perror("sigaction");
		return 2;
	}
	if (osa.sa_handler == SIG_DFL) {
		fprintf(stderr, "Go runtime did not install signal handler\n");
		return 2;
	}
	// gccgo does not set SA_ONSTACK for SIGSEGV.
	if (getenv("GCCGO") == NULL && (osa.sa_flags&SA_ONSTACK) == 0) {