/*      $OpenBSD: longjmp.c,v 1.4 2002/02/18 11:27:45 art Exp $ */
/*
 *      Artur Grabowski <art@openbsd.org>, 2002 Public Domain.
 */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <setjmp.h>
#include <err.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/resource.h>


jmp_buf buf;

/*
 * When longjmp is passed the incorrect arg (0), it should translate it into
 * something better.
 *
 * The rlimit is here in case we start spinning.
 */
int
main(int argc, char **argv)
{
        struct rlimit rl;
        volatile int i, expect;
        int (*sj)(jmp_buf);
        void (*lj)(jmp_buf, int);
        int ch;
        extern char *__progname;

        sj = setjmp;
        lj = longjmp;

        while ((ch = getopt(argc, argv, "_")) != -1) {
                switch (ch) {
                case '_':
                        sj = _setjmp;
                        lj = _longjmp;
                        break;
                default:
                        fprintf(stderr, "Usage: %s [-_]\n", __progname);
                        exit(1);
                }
        }

        rl.rlim_cur = 2;
        rl.rlim_max = 2;
        if (setrlimit(RLIMIT_CPU, &rl) < 0)
                err(1, "setrlimit");

        expect = 0;
        i = (*sj)(buf);
        if (i == 0 && expect != 0)
                errx(1, "setjmp returns 0 on longjmp(.., 0)");
        if (expect == 0) {
                expect = -1;
                (*lj)(buf, 0);
        }

        expect = 0;
        i = (*sj)(buf);
        if (i != expect)
                errx(1, "bad return from setjmp %d/%d", expect, i);
        if (expect < 1000)
                (*lj)(buf, expect += 2);

        return 0;
}