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/*
* Program eltorito.c - Handle El Torito specific extensions to iso9660.
*
Written by Michael Fulbright <msf@redhat.com> (1996).
Copyright 1996 RedHat Software, Incorporated
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
static char rcsid[] ="$Id: eltorito.c,v 1.5 1997/03/08 17:27:01 eric Rel $";
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <fcntl.h>
/* #include <malloc.h> */
#include <stdlib.h>
#include "mkisofs.h"
#include "iso9660.h"
static struct eltorito_validation_entry valid_desc;
static struct eltorito_defaultboot_entry default_desc;
/*
* Check for presence of boot catalog. If it does not exist then make it
*/
void FDECL1(init_boot_catalog, const char *, path)
{
int bcat;
char * bootpath; /* filename of boot catalog */
char * buf;
struct stat statbuf;
bootpath = (char *) e_malloc(strlen(boot_catalog)+strlen(path)+2);
strcpy(bootpath, path);
if (bootpath[strlen(bootpath)-1] != '/')
{
strcat(bootpath,"/");
}
strcat(bootpath, boot_catalog);
/*
* check for the file existing
*/
#ifdef DEBUG_TORITO
printf("Looking for boot catalog file %s\n",bootpath);
#endif
if (!stat_filter(bootpath, &statbuf))
{
/*
* make sure its big enough to hold what we want
*/
if (statbuf.st_size == 2048)
{
/*
* printf("Boot catalog exists, so we do nothing\n");
*/
free(bootpath);
return;
}
else
{
fprintf(stderr, "A boot catalog exists and appears corrupted.\n");
fprintf(stderr, "Please check the following file: %s.\n",bootpath);
fprintf(stderr, "This file must be removed before a bootable CD can be done.\n");
free(bootpath);
exit(1);
}
}
/*
* file does not exist, so we create it
* make it one CD sector long
*/
bcat = open(bootpath, O_WRONLY | O_CREAT, S_IROTH | S_IRGRP | S_IRWXU );
if (bcat == -1)
{
fprintf(stderr, "Error creating boot catalog, exiting...\n");
perror("");
exit(1);
}
buf = (char *) e_malloc( 2048 );
write(bcat, buf, 2048);
close(bcat);
free(bootpath);
} /* init_boot_catalog(... */
void FDECL1(get_torito_desc, struct eltorito_boot_descriptor *, boot_desc)
{
int bootcat;
int checksum;
unsigned char * checksum_ptr;
struct directory_entry * de;
struct directory_entry * de2;
int i;
int nsectors;
memset(boot_desc, 0, sizeof(*boot_desc));
boot_desc->id[0] = 0;
memcpy(boot_desc->id2, ISO_STANDARD_ID, sizeof(ISO_STANDARD_ID));
boot_desc->version[0] = 1;
memcpy(boot_desc->system_id, EL_TORITO_ID, sizeof(EL_TORITO_ID));
/*
* search from root of iso fs to find boot catalog
*/
de2 = search_tree_file(root, boot_catalog);
if (!de2)
{
fprintf(stderr,"Uh oh, I cant find the boot catalog!\n");
exit(1);
}
set_731(boot_desc->bootcat_ptr,
(unsigned int) get_733(de2->isorec.extent));
/*
* now adjust boot catalog
* lets find boot image first
*/
de=search_tree_file(root, boot_image);
if (!de)
{
fprintf(stderr,"Uh oh, I cant find the boot image!\n");
exit(1);
}
/*
* we have the boot image, so write boot catalog information
* Next we write out the primary descriptor for the disc
*/
memset(&valid_desc, 0, sizeof(valid_desc));
valid_desc.headerid[0] = 1;
valid_desc.arch[0] = EL_TORITO_ARCH_x86;
/*
* we'll shove start of publisher id into id field, may get truncated
* but who really reads this stuff!
*/
if (publisher)
memcpy_max(valid_desc.id, publisher, strlen(publisher));
valid_desc.key1[0] = 0x55;
valid_desc.key2[0] = 0xAA;
/*
* compute the checksum
*/
checksum=0;
checksum_ptr = (unsigned char *) &valid_desc;
for (i=0; i<sizeof(valid_desc); i+=2)
{
/*
* skip adding in ckecksum word, since we dont have it yet!
*/
if (i == 28)
{
continue;
}
checksum += (unsigned int)checksum_ptr[i];
checksum += ((unsigned int)checksum_ptr[i+1])*256;
}
/*
* now find out the real checksum
*/
checksum = -checksum;
set_721(valid_desc.cksum, (unsigned int) checksum);
/*
* now make the initial/default entry for boot catalog
*/
memset(&default_desc, 0, sizeof(default_desc));
default_desc.boot_id[0] = EL_TORITO_BOOTABLE;
/*
* use default BIOS loadpnt
*/
set_721(default_desc.loadseg, 0);
default_desc.arch[0] = EL_TORITO_ARCH_x86;
/*
* figure out size of boot image in sectors, for now hard code to
* assume 512 bytes/sector on a bootable floppy
*/
nsectors = ((de->size + 511) & ~(511))/512;
printf("\nSize of boot image is %d sectors -> ", nsectors);
/*
* choose size of emulated floppy based on boot image size
*/
if (nsectors == 2880 )
{
default_desc.boot_media[0] = EL_TORITO_MEDIA_144FLOP;
printf("Emulating a 1.44 meg floppy\n");
}
else if (nsectors == 5760 )
{
default_desc.boot_media[0] = EL_TORITO_MEDIA_288FLOP;
printf("Emulating a 2.88 meg floppy\n");
}
else if (nsectors == 2400 )
{
default_desc.boot_media[0] = EL_TORITO_MEDIA_12FLOP;
printf("Emulating a 1.2 meg floppy\n");
}
else
{
fprintf(stderr,"\nError - boot image is not the an allowable size.\n");
exit(1);
}
/*
* FOR NOW LOAD 1 SECTOR, JUST LIKE FLOPPY BOOT!!!
*/
nsectors = 1;
set_721(default_desc.nsect, (unsigned int) nsectors );
#ifdef DEBUG_TORITO
printf("Extent of boot images is %d\n",get_733(de->isorec.extent));
#endif
set_731(default_desc.bootoff,
(unsigned int) get_733(de->isorec.extent));
/*
* now write it to disk
*/
bootcat = open(de2->whole_name, O_RDWR);
if (bootcat == -1)
{
fprintf(stderr,"Error opening boot catalog for update.\n");
perror("");
exit(1);
}
/*
* write out
*/
write(bootcat, &valid_desc, 32);
write(bootcat, &default_desc, 32);
close(bootcat);
} /* get_torito_desc(... */
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.