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/*
* Copyright (c) 1992, 1993, 1996
* Berkeley Software Design, Inc. 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 Berkeley Software
* Design, Inc.
*
* THIS SOFTWARE IS PROVIDED BY Berkeley Software Design, Inc. ``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 Berkeley Software Design, Inc. 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.
*
* BSDI doscmd_loader.c,v 2.3 1996/04/08 19:32:33 bostic Exp
*
* $FreeBSD$
*/
#include <stdio.h>
#include <stdlib.h>
#include <a.out.h>
/*
* reserve space in "low" memory for the interrupt vector table
*/
static const char filler[4096] = { 0, };
#define _PATH_DOS_KERNEL_DIR "/usr/libexec/"
#define _PATH_DOS_KERNEL "doscmd.kernel"
int
load_kernel(void)
{
FILE *fp;
struct exec exec;
int start_address;
if ((fp = fopen(_PATH_DOS_KERNEL, "r")) == NULL &&
(fp = fopen("obj/" _PATH_DOS_KERNEL, "r")) == NULL &&
(fp = fopen(_PATH_DOS_KERNEL_DIR _PATH_DOS_KERNEL, "r")) == NULL &&
(fp = fopen(getenv("DOS_KERNEL"), "r")) == NULL)
err(1, "load_kernel");
if (fread(&exec, sizeof(exec), 1, fp) != 1 || N_GETMAGIC(exec) != OMAGIC)
errx(1, "bad kernel file format");
start_address = exec.a_entry & (~(getpagesize() - 1));
if (brk(start_address + exec.a_text + exec.a_data + exec.a_bss) < 0)
err(1, "load_kernel");
fread((char *)start_address, exec.a_text + exec.a_data, 1, fp);
bzero((char *)(start_address + exec.a_text + exec.a_data), exec.a_bss);
fclose(fp);
return(exec.a_entry);
}
void
main(int argc, char **argv, char **environ)
{
void (*entry_point)();
#ifndef __FreeBSD__
int fd = open("/dev/mem", 0);
#endif
setgid(getgid());
setuid(getuid());
#ifndef __FreeBSD__
if (fd < 0)
err(1, "/dev/mem");
#endif
entry_point = (void (*)()) load_kernel();
#ifndef __FreeBSD__
if (read(fd, 0, 0x500 != 0x500))
err(1, "/dev/mem");
close(fd);
#endif
(*entry_point)(argc, argv, environ);
errx(1, "return from doscmd kernel???");
}
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