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package partition_table::bsd;
use diagnostics;
use strict;
use vars qw(@ISA);
@ISA = qw(partition_table::raw);
use common;
use partition_table::raw;
use partition_table;
use c;
#- very bad and rough handling :(
my %pt_typeToDos = (
8 => 0x83,
1 => 0x82,
);
my %pt_typeFromDos = reverse %pt_typeToDos;
my ($main_format, $main_fields) = list2kv(
I => 'magic',
S => 'type',
S => 'subtype',
a16 => 'typename',
a16 => 'packname',
I => 'secsize',
I => 'nsectors',
I => 'ntracks',
I => 'ncylinders',
I => 'secpercyl',
I => 'secprtunit',
S => 'sparespertrack',
S => 'sparespercyl',
I => 'acylinders',
S => 'rpm',
S => 'interleave',
S => 'trackskew',
S => 'cylskew',
I => 'headswitch',
I => 'trkseek',
I => 'flags',
a20 => 'drivedata',
a20 => 'spare',
I => 'magic2',
S => 'checksum',
S => 'npartitions',
I => 'bbsize',
I => 'sbsize',
a128 => 'partitions',
a236 => 'blank',
);
$main_format = join '', @$main_format;
my @fields = qw(size start fsize pt_type frag cpg);
my $format = "I I I C C S";
my $magic = 0x82564557;
my $nb_primary = 8;
my $offset = 0x40;
sub use_pt_type { 1 }
sub read_one {
my ($hd, $sector) = @_;
my $tmp;
my $F = partition_table::raw::openit($hd) or die "failed to open device";
c::lseek_sector(fileno($F), $sector, $offset) or die "reading of partition in sector $sector failed";
sysread $F, $tmp, psizeof($main_format) or die "error while reading partition table in sector $sector";
my %info; @info{@$main_fields} = unpack $main_format, $tmp;
#- TODO verify checksum
my $size = psizeof($format);
my @pt = map {
my %h; @h{@fields} = unpack $format, $_;
fs::type::set_pt_type(\%h, $pt_typeToDos{$h{pt_type}} || $h{pt_type});
\%h;
} $info{partitions} =~ /(.{$size})/g;
#- check magic number
$info{magic} == $magic or die "bad magic number on disk $hd->{device}";
$info{magic2} == $magic or die "bad magic number on disk $hd->{device}";
[ @pt ], \%info;
}
# write the partition table (and extended ones)
# for each entry, it uses fields: start, size, pt_type, active
sub write($$$;$) {
my ($hd, $sector, $pt, $info) = @_;
#- handle testing for writing partition table on file only!
my $F;
if ($::testing) {
my $file = "/tmp/partition_table_$hd->{device}";
open $F, ">$file" or die "error opening test file $file";
} else {
$F = partition_table::raw::openit($hd, 2) or die "error opening device $hd->{device} for writing";
c::lseek_sector(fileno($F), $sector, $offset) or return 0;
}
#- TODO compute checksum
$info->{npartitions} = $nb_primary; #- is it ok?
@$pt == $nb_primary or die "partition table does not have $nb_primary entries";
$info->{partitions} = join '', map {
local $_->{pt_type} = $pt_typeFromDos{$_->{pt_type}} || $_->{pt_type};
pack $format, @$_{@fields};
} @$pt;
syswrite $F, pack($main_format, @$info{@$main_fields}), psizeof($main_format) or return 0;
1;
}
sub info {
my ($hd) = @_;
my $dtype_scsi = 4; #- taken from fdisk, removed unused one,
my $dtype_ST506 = 6; #- see fdisk for more
{
magic => $magic,
magic2 => $magic,
dtype => $hd->{device} =~ /^sd/ ? $dtype_scsi : $dtype_ST506,
secsize => $common::SECTORSIZE,
ncylinders => $hd->{geom}{cylinders},
secpercyl => $hd->cylinder_size,
secprtunit => $hd->{geom}{totalsectors},
rpm => 3600,
interleave => 1,
trackskew => 0,
cylskew => 0,
headswitch => 0,
trkseek => 0,
bbsize => 8192, #- size of boot area, with label
sbsize => 8192, #- max size of fs superblock
};
}
sub initialize {
my ($class, $hd) = @_;
$hd->{primary} = { raw => [ ({}) x $nb_primary ], info => info($hd) };
bless $hd, $class;
}
sub first_usable_sector { 2048 }
1;
|
