//#include <asm/sigcontext.h>
#include <signal.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>
//#include <ucontext.h>

volatile int child_blocked;
volatile sig_atomic_t got_it;

#if defined(__i386)
#define HAVE_LEGACY
void handle(int signal, struct sigcontext sc)
{
	child_blocked = sc.oldmask == (1 << (SIGCHLD-1));
	got_it = 1;
}
#elif defined(__amd64)
#define HAVE_LEGACY
void handle(int signal, struct ucontext uc)
{
	child_blocked = ((struct sigcontext*)&uc.uc_mcontext)->oldmask == (1 << (SIGCHLD-1));
	got_it = 1;
}
#elif defined(__mc68000)
#define HAVE_LEGACY
void handle(int signal, int code, struct sigcontext *sc)
{
	child_blocked = sc->sc_mask == (1 << (SIGCHLD-1));
	got_it = 1;
}
#endif


void handle_siginfo(int signal, siginfo_t * info, void *ctx)
{
	child_blocked = sigismember(&((ucontext_t*)ctx)->uc_sigmask, SIGCHLD);
	got_it = 1;
}

int main(void)
{
	struct sigaction sa;
	sigset_t set;

#ifdef HAVE_LEGACY
	sa.sa_flags = 0;
	sa.sa_handler = handle;
	sigemptyset(&sa.sa_mask);
	sigaction(SIGUSR1, &sa, NULL);
	sigemptyset(&set);
	sigaddset(&set, SIGCHLD);
	sigprocmask(SIG_SETMASK, &set, NULL);
	got_it = 0;
	kill(getpid(), SIGUSR1);
	while(got_it == 0);
	sigprocmask(SIG_SETMASK, NULL, &set);
	printf("%d %d\n", child_blocked, sigismember(&set, SIGCHLD));
#endif

	got_it = 0;
	sa.sa_flags = SA_SIGINFO;
	sa.sa_sigaction = handle_siginfo;
	sigaction(SIGUSR1, &sa, NULL);
	sigemptyset(&set);
	sigaddset(&set, SIGCHLD);
	sigprocmask(SIG_SETMASK, &set, NULL);
	got_it = 0;
	kill(getpid(), SIGUSR1);
	while(got_it == 0);
	sigprocmask(SIG_SETMASK, NULL, &set);
	printf("%d %d\n", child_blocked, sigismember(&set, SIGCHLD));
}