2 ## -----------------------------------------------------------------------
4 ## Copyright 2002-2008 H. Peter Anvin - All Rights Reserved
6 ## This program is free software; you can redistribute it and/or modify
7 ## it under the terms of the GNU General Public License as published by
8 ## the Free Software Foundation, Inc., 53 Temple Place Ste 330,
9 ## Boston MA 02111-1307, USA; either version 2 of the License, or
10 ## (at your option) any later version; incorporated herein by reference.
12 ## -----------------------------------------------------------------------
15 # Creates a blank MS-DOS formatted hard disk image
23 use IO::Handle; # For flush()
25 sub absolute_path($) {
29 return $f if ( $f =~ /^\// );
31 $c = '' if ( $c eq '/' );
38 '($sysname, $nodename, $release, $version, $machine) = POSIX::uname(); '.
39 "return \$sysname eq \'Linux\'; }";
43 # Get a 32-bit random number
47 if (open($rfd, "< /dev/urandom\0") && read($rfd, $rnd, 4) == 4) {
48 $rid = unpack("V", $rnd);
51 close($rfd) if (defined($rfd));
52 return $rid if (defined($rid));
54 # This sucks but is better than nothing...
55 return ($$+time()) & 0xffffffff;
58 $is_linux = is_linux();
68 while (defined($a = shift(@ARGV))) {
70 foreach $o ( split(//, substr($a,1)) ) {
81 ($file,$c,$h,$s) = @args;
82 $c += 0; $h += 0; $s += 0;
85 $pentry = 2 if ( $opt{'2'} );
86 $pentry = 3 if ( $opt{'3'} );
87 $pentry = 4 if ( $opt{'4'} );
94 if ( $opt{'M'} && $h && $s ) {
95 # Specify size in megabytes, not in cylinders
96 $c = ($c*1024*2)/($h*$s);
101 if ( $c == 0 && $file ne '' ) {
103 if ( sysopen(OUTPUT, $file, O_RDWR, 0666) ) {
106 if ( (@filestat = stat(OUTPUT)) && S_ISREG($filestat[2]) ) {
107 $len = $filestat[7] >> 9;
108 } elsif ( $is_linux && S_ISBLK($filestat[2]) ) {
109 $blksize = pack("L!", 0);
110 if ( ioctl(OUTPUT, $BLKGETSIZE, $blksize) == 0 ) {
111 $len = unpack("L!", $blksize); # In 512-byte sectors!
117 print STDERR "$0: $file: don't know how to determine the size of this device\n";
124 if ( $file eq '' || $c < 1 || $h < 1 || $h > 256 || $s < 1 || $s > 63 ) {
125 print STDERR "Usage: $0 [-doFMz4][-i id] file c h s (max: 1024 256 63)\n";
126 print STDERR " -d add DOSEMU header\n";
127 print STDERR " -o print filesystem offset to stdout\n";
128 print STDERR " -F format partition as FAT32\n";
129 print STDERR " -M \"c\" argument is megabytes, calculate cylinders\n";
130 print STDERR " -z use zipdisk geometry (h=64 s=32)\n";
131 print STDERR " -4 use partition entry 4 (standard for zipdisks)\n";
132 print STDERR " -i specify the MBR ID\n";
137 print STDERR "Warning: more than 1024 cylinders ($c).\n";
138 print STDERR "Not all BIOSes will be able to boot this device.\n";
144 $cylsize = $h*$s*512;
147 sysopen(OUTPUT, $file, O_CREAT|O_RDWR|O_TRUNC, 0666)
148 or die "$0: Cannot open: $file\n";
152 # Print out DOSEMU header, if requested
154 $emuhdr = "DOSEMU\0" . pack("VVVV", $h, $s, $c, 128);
155 $emuhdr .= "\0" x (128 - length($emuhdr));
156 print OUTPUT $emuhdr;
159 # Print the MBR and partition table
161 while ( $line = <DATA> ) {
163 foreach $byte ( split(/\s+/, $line) ) {
164 $mbr .= chr(hex($byte));
167 if ( length($mbr) > 440 ) {
168 die "$0: Bad MBR code\n";
171 $mbr .= "\0" x (440 - length($mbr));
177 $mbr .= pack("V", $id); # Offset 440: MBR ID
178 $mbr .= "\0\0"; # Offset 446: actual partition table
182 # Print partition table
183 $psize = $c*$h*$s-$s;
184 $bhead = ($h > 1) ? 1 : 0;
186 $bcyl = ($h > 1) ? 0 : 1;
188 $esect = $s + ((($cc-1) & 0x300) >> 2);
189 $ecyl = ($cc-1) & 0xff;
192 } elsif ( $psize > 65536 ) {
197 for ( $i = 1 ; $i <= 4 ; $i++ ) {
198 if ( $i == $pentry ) {
199 print OUTPUT pack("CCCCCCCCVV", 0x80, $bhead, $bsect, $bcyl, $fstype,
200 $ehead, $esect, $ecyl, $s, $psize);
202 print OUTPUT "\0" x 16;
205 print OUTPUT "\x55\xaa";
208 $totalsize = $c*$h*$s;
211 $track = "\0" x (512*$s);
213 # Print fractional track
214 print OUTPUT "\0" x (512 * ($s-1));
216 for ( $i = 1 ; $i < $tracks ; $i++ ) {
220 # Print mtools temp file
222 while ( !defined($tmpdir) ) {
223 $tmpdir = "/tmp/mkdiskimage.$$.".($n++);
224 if ( !mkdir($tmpdir, 0700) ) {
225 die "$0: Failed to make temp directory: $tmpdir\n"
231 $cfgfile = $tmpdir.'/mtools.conf';
232 $imglink = $tmpdir.'/disk.img';
233 die "$0: Failed to create symlink $imglink\n"
234 if ( !symlink(absolute_path($file), $imglink) );
236 $header_size = ($opt{'d'} ? 128 : 0);
238 # Start of filesystem
239 $offset = $s*512 + $header_size;
241 # Start of partition table entry
242 $pstart = $header_size + 446 + 16*($pentry-1);
244 open(MCONFIG, "> ${cfgfile}") or die "$0: Cannot make mtools config\n";
245 print MCONFIG "drive z:\n";
246 print MCONFIG "file=\"${imglink}\"\n";
247 print MCONFIG "cylinders=${c}\n";
248 print MCONFIG "heads=${h}\n";
249 print MCONFIG "sectors=${s}\n";
250 print MCONFIG "offset=${offset}\n";
251 print MCONFIG "mformat_only\n";
254 # Output the filesystem offset to stdout if appropriate
259 $ENV{'MTOOLSRC'} = $cfgfile;
261 system('mformat', '-F', 'z:');
263 system('mformat', 'z:');
271 # MTOOLS doesn't write the bsHiddenSecs field correctly
272 seek(OUTPUT, $offset + 0x1c, 0);
273 print OUTPUT pack("V", ($offset-$header_size)>>9);
275 # Set the partition type
278 $fstype = 0x0c; # FAT32 LBA
284 $fstype = 0x0e; # FAT16 LBA
285 } elsif ( $psize > 65536 ) {
286 $fstype = 0x06; # FAT16 > 32MB
288 $fstype = 0x04; # FAT16 <= 32MB
290 seek(OUTPUT, $offset + 0x36, 0);
291 read(OUTPUT, $fsname, 8);
293 # FAT12: adjust partition type
294 if ( $fsname eq 'FAT12 ' ) {
295 $fstype = 0x01; # FAT12
298 seek(OUTPUT, $pstart+4, 0);
299 print OUTPUT pack("C", $fstype);
303 # Just in case this is a block device, try to flush the partition table
305 ioctl(OUTPUT, $BLKRRPART, 0);