Source to i386/stand/boot.c
/*-
* Copyright (c) 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* William Jolitz.
*
* 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.
*/
#ifndef lint
static char copyright[] =
"@(#) Copyright (c) 1990, 1993\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
static char sccsid[] = "@(#)boot.c 8.1 (Berkeley) 6/11/93";
#endif /* not lint */
#include <sys/param.h>
#include <sys/reboot.h>
#include <a.out.h>
#include <setjmp.h>
#include <stand/saio.h>
/*
* Boot program... arguments from lower-level bootstrap determine
* whether boot stops to ask for system name and which device
* boot comes from.
*/
char line[100] = UNIX;
extern int opendev, bootdev, cyloffset;
int retry = 0;
extern jmp_buf exception;
main(howto, dev, off)
{
int io;
if((dev&B_MAGICMASK) == B_DEVMAGIC) {
bootdev = dev;
cyloffset = off;
} else goto again;
if(_setjmp(exception)) {
close(io);
printf("- load aborted\n");
again:
howto = RB_SINGLE|RB_ASKNAME;
cyloffset = 0;
}
for (;;) {
if (howto & RB_ASKNAME) {
char *cp;
printf("Boot: ");
gets(line);
/* process additional flags if any */
if(cp = (char *)index(line, ' ')) {
howto = strtol (cp, 0, 0);
*cp = '\0';
}
cyloffset = 0;
} else
printf("Boot: %s\n", line);
if (line[0] == 0) {
strcpy(line, UNIX);
printf("Boot: %s\n", line);
}
io = open(line, 0);
if (io >= 0) {
copyunix(io, howto);
goto again;
} else if (++retry > 2)
goto again;
}
}
/*ARGSUSED*/
copyunix(io, howto)
register io;
{
struct exec x;
int i;
char *addr,c;
i = read(io, (char *)&x, sizeof x);
if (i != sizeof x ||
(x.a_magic != 0407 && x.a_magic != 0413 && x.a_magic != 0410)) {
printf("Bad format\n");
return;
}
printf("%d", x.a_text);
if (x.a_magic == 0413 && lseek(io, 0x400, 0) == -1)
goto shread;
if (read(io, (char *)0, x.a_text) != x.a_text)
goto shread;
addr = (char *)x.a_text;
if (x.a_magic == 0413 || x.a_magic == 0410)
while ((int)addr & CLOFSET)
*addr++ = 0;
printf("+%d", x.a_data);
if (read(io, addr, x.a_data) != x.a_data)
goto shread;
addr += x.a_data;
printf("+%d", x.a_bss);
x.a_bss += 128*512; /* slop */
for (i = 0; i < x.a_bss; i++)
*addr++ = 0;
/* mask high order bits corresponding to relocated system base */
x.a_entry &= 0x000fffff;
printf(" start 0x%x\n", x.a_entry);
if(c=scankbd())
_longjmp(&exception,1);
i = (*((int (*)()) x.a_entry))(howto, opendev, 0, cyloffset);
if (i) printf("exit %d\n", i) ;
return;
shread:
printf("Short read\n");
return;
}