BSD 4_4 release

[unix-history] / usr / src / sys / 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;
}