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/*-

 * Copyright (c) 1990 The Regents of the University of California.

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 * 3. All advertising materials mentioning features or use of this software

 *    must display the following acknowledgement:

 *      This product includes software developed by the University of

 *      California, Berkeley and its contributors.

 * 4. Neither the name of the University nor the names of its contributors

 *    may be used to endorse or promote products derived from this software

 *    without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND

 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE

 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 * SUCH DAMAGE.

 */

#if defined(LIBC_SCCS) && !defined(lint)

static char sccsid[] = "@(#)crt0.c      5.7 (Berkeley) 7/3/91";

#endif /* LIBC_SCCS and not lint */

/*

 *      C start up routine.

 *      Robert Henry, UCB, 20 Oct 81

 *

 *      We make the following (true) assumption:

 *      1) The only register variable that we can trust is ebp,

 *      which points to the base of the kernel calling frame.

 */

char **environ = (char **)0;

static int fd;

/*

asm(".text");

asm(".long 0xc000c000");

*/

extern  unsigned char   etext;

extern  unsigned char   eprol asm ("eprol");

/* extern                       start() asm("start"); */

_start(int arg)

{

        struct kframe {

                int     kargc;

                char    *kargv[1];      /* size depends on kargc */

                char    kargstr[1];     /* size varies */

                char    kenvstr[1];     /* size varies */

        };

        /*

         *      ALL REGISTER VARIABLES!!!

         */

        register struct kframe *kfp;    /* r10 */

        register char **targv;

        register char **argv;

        extern int errno;

        extern void _mcleanup();

#ifdef lint

        kfp = 0;

        initcode = initcode = 0;

#else not lint

# if 0

        asm("lea 4(%ebp),%ebx");        /* catch it quick */

# else

        kfp = (struct kframe *)&(((int *)(&arg))[-1]);

# endif

#endif not lint

        for (argv = targv = &kfp->kargv[0]; *targv++; /* void */)

                /* void */ ;

        if (targv >= (char **)(*argv))

                --targv;

        environ = targv;

asm("eprol:");

#ifdef paranoid

        /*

         * The standard I/O library assumes that file descriptors 0, 1, and 2

         * are open. If one of these descriptors is closed prior to the start

         * of the process, I/O gets very confused. To avoid this problem, we

         * insure that the first three file descriptors are open before calling

         * main(). Normally this is undefined, as it adds two unnecessary

         * system calls.

         */

        do      {

                fd = open("/dev/null", 2);

        } while (fd >= 0 && fd < 3);

        close(fd);

#endif paranoid

#ifdef MCRT0

        atexit(_mcleanup);

        monstartup(&eprol, &etext);

#endif MCRT0

        errno = 0;

        exit(main(kfp->kargc, argv, environ));

}

#ifdef CRT0

/*

 * null mcount and moncontrol,

 * just in case some routine is compiled for profiling

 */

moncontrol(val)

        int val;

{

}

asm(".globl mcount");

asm("mcount: ret");

#endif CRT0