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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
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