package partition_table; # $Id$

use diagnostics;
use strict;
use vars qw(@ISA %EXPORT_TAGS @EXPORT_OK @important_types @important_types2 @fields2save @bad_types);

@ISA = qw(Exporter);
%EXPORT_TAGS = (
    types => [ qw(type2name type2fs name2type fs2type isExtended isExt2 isThisFs isTrueFS isSwap isDos isWin isFat isSunOS isOtherAvailableFS isPrimary isRawLVM isRawRAID isRAID isLVM isNT isMountableRW isNonMountable isPartOfLVM isPartOfRAID isPartOfLoopback isApplePartMap isLoopback isMounted isBusy isSpecial maybeFormatted isApple isAppleBootstrap isEfi) ],
);
@EXPORT_OK = map { @$_ } values %EXPORT_TAGS;


use common;
use partition_table::raw;
use detect_devices;
use log;

@important_types = ('Linux native', 'Linux swap', 
		    if_(arch() =~ /i.86/, 'Journalised FS: ext3', 'Journalised FS: ReiserFS', 'Journalised FS: JFS', 'Journalised FS: XFS', 'DOS FAT16', 'FAT32'),
			if_(arch() =~ /ia64/, 'Journalised FS: ext3', 'Journalised FS: ReiserFS', 'Journalised FS: XFS', 'FAT32'),
			if_(arch() =~ /x86_64/, 'Journalised FS: ext3', 'Journalised FS: ReiserFS', 'Journalised FS: XFS', 'FAT32'),
		    if_(arch() =~ /ppc/, 'Journalised FS: ext3', 'Journalised FS: ReiserFS', 'Journalised FS: JFS', 'Journalised FS: XFS', 'Apple HFS Partition', 'Apple Bootstrap'));
@important_types2 = ('Linux RAID', 'Linux Logical Volume Manager partition');

@fields2save = qw(primary extended totalsectors isDirty needKernelReread);

@bad_types = ('Empty', 'DOS 3.3+ Extended Partition', 'Win95: Extended partition, LBA-mapped', 'Linux extended partition');

my %types = (
  0x0 => 'Empty',
if_(arch() =~ /^ppc/, 
  0x183 => 'Journalised FS: ReiserFS',
  0x283 => 'Journalised FS: XFS',
  0x383 => 'Journalised FS: JFS',
  0x483 => 'Journalised FS: ext3',
  0x401	=> 'Apple Partition',
  0x401	=> 'Apple Bootstrap',
  0x402	=> 'Apple HFS Partition',
), if_(arch() =~ /^i.86/,
  0x183 => 'Journalised FS: ReiserFS',
  0x283 => 'Journalised FS: XFS',
  0x383 => 'Journalised FS: JFS',
  0x483 => 'Journalised FS: ext3',
), if_(arch() =~ /^ia64/,
  0x100 => 'Various',
  0x183 => 'Journalised FS: ReiserFS',
  0x283 => 'Journalised FS: XFS',
  0x483 => 'Journalised FS: ext3',
), if_(arch() =~ /^x86_64/,
  0x183 => 'Journalised FS: ReiserFS',
  0x283 => 'Journalised FS: XFS',
  0x483 => 'Journalised FS: ext3',
), if_(arch() =~ /^sparc/,
  0x1 => 'SunOS boot',
  0x2 => 'SunOS root',
  0x3 => 'SunOS swap',
  0x4 => 'SunOS usr',
  0x5 => 'Whole disk',
  0x6 => 'SunOS stand',
  0x7 => 'SunOS var',
  0x8 => 'SunOS home',
), if_(arch() =~ /^i.86/,
  0x1 => 'DOS 12-bit FAT',
  0x2 => 'XENIX root',
  0x3 => 'XENIX /usr',
  0x4 => 'DOS 16-bit FAT (up to 32M)',
  0x5 => 'DOS 3.3+ Extended Partition',
  0x6 => 'DOS FAT16',
  0x7 => 'NTFS (or HPFS)',
  0x8 => 'OS/2 (v1.0-1.3 only) / AIX boot partition / SplitDrive / Commodore DOS / DELL partition spanning multiple drives / QNX 1.x and 2.x ("qny")',
),
  0x9 => 'AIX data partition / Coherent filesystem / QNX 1.x and 2.x ("qnz")',
  0xa => 'OS/2 Boot Manager / Coherent swap partition / OPUS',
  0xb => 'FAT32',
  0xc => 'Win98 FAT32, LBA-mapped',
  0xe => 'Win95: DOS 16-bit FAT, LBA-mapped',
  0xf => 'Win95: Extended partition, LBA-mapped',
  0x10 => 'OPUS (?)',
  0x11 => 'Hidden DOS 12-bit FAT',
  0x12 => 'Compaq/HP config partition',
  0x14 => 'Hidden DOS 16-bit FAT <32M',
  0x16 => 'Hidden DOS 16-bit FAT >=32M',
  0x17 => 'Hidden IFS (e.g., HPFS)',
  0x18 => 'AST Windows swapfile',
  0x1b => 'Hidden WIN95 OSR2 32-bit FAT',
  0x1c => 'Hidden WIN95 OSR2 32-bit FAT, LBA-mapped',
  0x1e => 'Hidden FAT95',
  0x22 => 'Used for Oxygen Extended Partition Table by ekstazya@sprint.ca.',
  0x24 => 'NEC DOS 3.x',
  0x35 => 'JFS (OS/2)',
  0x38 => 'THEOS ver 3.2 2gb partition',
  0x39 => 'THEOS ver 4 spanned partition',
  0x3a => 'THEOS ver 4 4gb partition',
  0x3b => 'THEOS ver 4 extended partition',
  0x3c => 'PartitionMagic recovery partition',
  0x40 => 'Venix 80286',
  0x41 => 'Linux/MINIX (sharing disk with DRDOS) / Personal RISC Boot / PPC PReP (Power PC Reference Platform) Boot',
  0x42 => 'Windows Dynamic Partition',
  0x43 => 'Linux native (sharing disk with DRDOS)',
  0x45 => 'EUMEL/Elan',
  0x46 => 'EUMEL/Elan 0x46',
  0x47 => 'EUMEL/Elan 0x47',
  0x48 => 'EUMEL/Elan 0x48',
  0x4d => 'QNX4.x',
  0x4e => 'QNX4.x 2nd part',
  0x4f => 'QNX4.x 3rd part / Oberon partition',
  0x50 => 'OnTrack Disk Manager (older versions) RO',
  0x51 => 'OnTrack Disk Manager RW (DM6 Aux1) / Novell',
  0x52 => 'CP/M / Microport SysV/AT',
  0x53 => 'Disk Manager 6.0 Aux3',
  0x54 => 'Disk Manager 6.0 Dynamic Drive Overlay',
  0x55 => 'EZ-Drive',
  0x56 => 'Golden Bow VFeature Partitioned Volume. / DM converted to EZ-BIOS',
  0x57 => 'DrivePro',
  0x5c => 'Priam EDisk',
  0x61 => 'SpeedStor',
  0x63 => 'Unix System V (SCO, ISC Unix, UnixWare, ...), Mach, GNU Hurd',
  0x64 => 'PC-ARMOUR protected partition / Novell Netware 2.xx',
  0x65 => 'Novell Netware 3.xx or 4.xx',
  0x67 => 'Novell',
  0x68 => 'Novell 0x68',
  0x69 => 'Novell 0x69',
  0x70 => 'DiskSecure Multi-Boot',
  0x75 => 'IBM PC/IX',
  0x80 => 'MINIX until 1.4a',
  0x81 => 'MINIX since 1.4b, early Linux / Mitac disk manager',
  0x82 => 'Linux swap',
  0x83 => 'Linux native',
  0x84 => 'OS/2 hidden C: drive / Hibernation partition',
  0x85 => 'Linux extended partition',
  0x86 => 'Old Linux RAID partition superblock / NTFS volume set',
  0x87 => 'NTFS volume set',
  0x8a => 'Linux Kernel Partition (used by AiR-BOOT)',
  0x8e => 'Linux Logical Volume Manager partition',
  0x93 => 'Amoeba',
  0x94 => 'Amoeba bad block table',
  0x99 => 'DCE376 logical drive',
  0xa0 => 'IBM Thinkpad hibernation partition / Phoenix NoteBIOS Power Management "Save-to-Disk" partition',
  0xa5 => 'BSD/386, 386BSD, NetBSD, FreeBSD',
  0xa6 => 'OpenBSD',
  0xa7 => 'NEXTSTEP',
  0xa9 => 'NetBSD',
  0xaa => 'Olivetti Fat 12 1.44Mb Service Partition',
  0xb7 => 'BSDI filesystem',
  0xb8 => 'BSDI swap partition',
  0xbe => 'Solaris boot partition',
  0xc0 => 'CTOS / REAL/32 secure small partition',
  0xc1 => 'DRDOS/secured (FAT-12)',
  0xc4 => 'DRDOS/secured (FAT-16, < 32M)',
  0xc6 => 'DRDOS/secured (FAT-16, >= 32M) / Windows NT corrupted FAT16 volume/stripe set',
  0xc7 => 'Windows NT corrupted NTFS volume/stripe set / Syrinx boot',
  0xcb => 'reserved for DRDOS/secured (FAT32)',
  0xcc => 'reserved for DRDOS/secured (FAT32, LBA)',
  0xcd => 'CTOS Memdump?',
  0xce => 'reserved for DRDOS/secured (FAT16, LBA)',
  0xd0 => 'REAL/32 secure big partition',
  0xd1 => 'Old Multiuser DOS secured FAT12',
  0xd4 => 'Old Multiuser DOS secured FAT16 <32M',
  0xd5 => 'Old Multiuser DOS secured extended partition',
  0xd6 => 'Old Multiuser DOS secured FAT16 >=32M',
  0xd8 => 'CP/M-86',
  0xdb => 'Digital Research CP/M, Concurrent CP/M, Concurrent DOS / CTOS (Convergent Technologies OS -Unisys) / KDG Telemetry SCPU boot',
  0xdd => 'Hidden CTOS Memdump?',
  0xe1 => 'DOS access or SpeedStor 12-bit FAT extended partition',
  0xe3 => 'DOS R/O or SpeedStor',
  0xe4 => 'SpeedStor 16-bit FAT extended partition < 1024 cyl.',
  0xeb => 'BeOS',
  0xee => 'EFI GPT',
  0xef => 'EFI (FAT-12/16/32)',
  0xf1 => 'SpeedStor 0xf1',
  0xf2 => 'DOS 3.3+ secondary partition',
  0xf4 => 'SpeedStor large partition / Prologue single-volume partition',
  0xf5 => 'Prologue multi-volume partition',
  0xfd => 'Linux RAID',
  0xfe => 'SpeedStor > 1024 cyl. or LANstep / IBM PS/2 IML (Initial Microcode Load) partition, located at the end of the disk. / Windows NT Disk Administrator hidden partition / Linux Logical Volume Manager partition (old)',
  0xff => 'Xenix Bad Block Table',
);

my %type2fs = (
arch() =~ /^ppc/ ? (
  0x07 => 'hpfs',
) : (
  0x07 => 'ntfs',
),
arch() !~ /sparc/ ? (
  0x01 => 'vfat',
  0x04 => 'vfat',
  0x05 => 'ignore',
  0x06 => 'vfat',
) : (
  0x01 => 'ufs',
  0x02 => 'ufs',
  0x04 => 'ufs',
  0x06 => 'ufs',
  0x07 => 'ufs',
  0x08 => 'ufs',
),
  0x0b => 'vfat',
  0x0c => 'vfat',
  0x0e => 'vfat',
  0x1b => 'vfat',
  0x1c => 'vfat',
  0x1e => 'vfat',
  0x82 => 'swap',
  0x83 => 'ext2',
  0xef => 'vfat',
  0x183=> 'reiserfs',
  0x283=> 'xfs',
  0x383=> 'jfs',
  0x483=> 'ext3',
  0x401 => 'apple',
  0x402 => 'hfs',
);

my %types_rev = reverse %types;
my %fs2type = reverse %type2fs;


1;

sub important_types { 
    my @l = (@important_types, if_($::expert, @important_types2, sort values %types));
    difference2(\@l, \@bad_types);
}

sub type2fs { $type2fs{$_[0]{type}} || $_[0]{type} }
sub fs2type { $fs2type{$_[0]} || $_[0] }
sub type2name { $types{$_[0]} || $_[0] }
sub name2type { 
    local ($_) = @_;
    /0x(.*)/ ? hex $1 : $types_rev{$_} || $_;
}

sub isEfi { arch() =~ /ia64/ && $_[0]{type} == 0xef }
sub isWholedisk { arch() =~ /^sparc/ && $_[0]{type} == 5 }
sub isExtended { arch() !~ /^sparc/ && ($_[0]{type} == 5 || $_[0]{type} == 0xf || $_[0]{type} == 0x85) }
sub isRawLVM { $_[0]{type} == 0x8e }
sub isRawRAID { $_[0]{type} == 0xfd }
sub isSwap { type2fs($_[0]) eq 'swap' }
sub isExt2 { type2fs($_[0]) eq 'ext2' }
sub isDos { arch() !~ /^sparc/ && $ {{ 1=>1, 4=>1, 6=>1 }}{$_[0]{type}} }
sub isWin { $ {{ 0xb=>1, 0xc=>1, 0xe=>1, 0x1b=>1, 0x1c=>1, 0x1e=>1 }}{$_[0]{type}} }
sub isFat { isDos($_[0]) || isWin($_[0]) }
sub isSunOS { arch() =~ /sparc/ && $ {{ 0x1=>1, 0x2=>1, 0x4=>1, 0x6=>1, 0x7=>1, 0x8=>1 }}{$_[0]{type}} }
sub isNT { arch() !~ /^sparc/ && $_[0]{type} == 0x7 }
sub isApple { type2fs($_[0]) eq 'apple' && defined $_[0]{isDriver} }
sub isAppleBootstrap { type2fs($_[0]) eq 'apple' && defined $_[0]{isBoot} }
sub isHiddenMacPart { defined $_[0]{isMap} }

sub isThisFs { type2fs($_[1]) eq $_[0] }
sub isTrueFS { member(type2fs($_[0]), qw(ext2 reiserfs xfs jfs ext3)) }

sub isOtherAvailableFS {  isEfi($_[0]) || isFat($_[0]) || isSunOS($_[0]) || isThisFs('hfs', $_[0]) || isThisFs('ntfs', $_[0]) } #- other OS that linux can access its filesystem
sub isMountableRW { (isTrueFS($_[0]) || isOtherAvailableFS($_[0])) && !isThisFs('ntfs', $_[0]) }
sub isNonMountable { isRawRAID($_[0]) || isRawLVM($_[0]) }

sub isPartOfLVM { defined $_[0]{lvm} }
sub isPartOfRAID { defined $_[0]{raid} }
sub isPartOfLoopback { defined $_[0]{loopback} }
sub isRAID { $_[0]{device} =~ /^md/ }
sub isLVM { $_[0]{VG_name} }
sub isLoopback { defined $_[0]{loopback_file} }
sub isMounted { $_[0]{isMounted} }
sub isBusy { isMounted($_[0]) || isPartOfRAID($_[0]) || isPartOfLVM($_[0]) || isPartOfLoopback($_[0]) }
sub isSpecial { isRAID($_[0]) || isLVM($_[0]) || isLoopback($_[0]) }
sub maybeFormatted { $_[0]{isFormatted} || !$_[0]{notFormatted} }


#- works for both hard drives and partitions ;p
sub description {
    my ($hd) = @_;
    my $win = $hd->{device_windobe};

    sprintf "%s%s (%s%s%s%s)", 
      $hd->{device}, 
      $win && " [$win:]", 
      formatXiB($hd->{totalsectors} || $hd->{size}, 512),
      $hd->{info} && ", $hd->{info}",
      $hd->{mntpoint} && ", " . $hd->{mntpoint},
      $hd->{type} && ", " . type2name($hd->{type});
}

sub isPrimary {
    my ($part, $hd) = @_;
    foreach (@{$hd->{primary}{raw}}) { $part eq $_ and return 1 }
    0;
}

sub adjustStartAndEnd {
    my ($hd, $part) = @_;

    $hd->adjustStart($part);
    $hd->adjustEnd($part);
}

sub verifyNotOverlap {
    my ($a, $b) = @_;
    $a->{start} + $a->{size} <= $b->{start} || $b->{start} + $b->{size} <= $a->{start};
}
sub verifyInside {
    my ($a, $b) = @_;
    $b->{start} <= $a->{start} && $a->{start} + $a->{size} <= $b->{start} + $b->{size};
}

sub verifyParts_ {
    foreach my $i (@_) {
	foreach (@_) {
	    next if !$i || !$_ || $i == $_ || isWholedisk($i) || isExtended($i); #- avoid testing twice for simplicity :-)
	    if (isWholedisk($_)) {
		verifyInside($i, $_) or
		  cdie sprintf("partition sector #$i->{start} (%s) is not inside whole disk (%s)!",
			       formatXiB($i->{size}, 512), formatXiB($_->{size}, 512));
	    } elsif (isExtended($_)) {
		verifyNotOverlap($i, $_) or
		  log::l(sprintf("warning partition sector #$i->{start} (%s) is overlapping with extended partition!",
				 formatXiB($i->{size}, 512))); #- only warning for this one is acceptable
	    } else {
		verifyNotOverlap($i, $_) or
		  cdie sprintf("partitions sector #$i->{start} (%s) and sector #$_->{start} (%s) are overlapping!",
			       formatXiB($i->{size}, 512), formatXiB($_->{size}, 512));
	    }
	}
    }
}
sub verifyParts {
    my ($hd) = @_;
    verifyParts_(get_normal_parts($hd));
}
sub verifyPrimary {
    my ($pt) = @_;
    $_->{start} > 0 || arch() =~ /^sparc/ || die "partition must NOT start at sector 0" foreach @{$pt->{normal}};
    verifyParts_(@{$pt->{normal}}, $pt->{extended});
}

sub assign_device_numbers {
    my ($hd) = @_;

    my $i = 1;
    my $start = 1; 
    
    #- on PPC we need to assign device numbers to the holes too - big FUN!
    #- not if it's an IBM machine using a DOS partition table though
    if (arch() =~ /ppc/ && detect_devices::get_mac_model() !~ /^IBM/) {
	#- first sort the normal parts
	$hd->{primary}{normal} = [sort { $a->{start} <=> $b->{start} } @{$hd->{primary}{normal}} ];
    
	#- now loop through them, assigning partition numbers - reserve one for the holes
	foreach (@{$hd->{primary}{normal}}) {
	    if ($_->{start} > $start) {
		log::l("PPC: found a hole on $hd->{prefix} before $_->{start}, skipping device..."); 
		$i++;
	    }
	    $_->{device} = $hd->{prefix} . $i;
	    $_->{devfs_device} = $hd->{devfs_prefix} . '/part' . $i;
	    $start = $_->{start} + $_->{size};
	    $i++;
	}
    } else {
	foreach (@{$hd->{primary}{raw}}) {
	    $_->{device} = $hd->{prefix} . $i;
	    $_->{devfs_device} = $hd->{devfs_prefix} . '/part' . $i;
	    $i++;
	}
	foreach (map { $_->{normal} } @{$hd->{extended} || []}) {
	    my $dev = $hd->{prefix} . $i;
	    push @{$hd->{partitionsRenumbered}}, [ $_->{device}, $dev ] if $_->{device} && $dev ne $_->{device};
	    $_->{device} = $dev;
	    $_->{devfs_device} = $hd->{devfs_prefix} . '/part' . $i;
	    $i++;
	}
    }

    #- try to figure what the windobe drive letter could be!
    #
    #- first verify there's at least one primary dos partition, otherwise it
    #- means it is a secondary disk and all will be false :(
    my ($c, @others) = grep { isFat($_) } @{$hd->{primary}{normal}};

    $i = ord 'C';
    $c->{device_windobe} = chr($i++) if $c;
    $_->{device_windobe} = chr($i++) foreach grep { isFat($_) } map { $_->{normal} } @{$hd->{extended}};
    $_->{device_windobe} = chr($i++) foreach @others;
}

sub remove_empty_extended {
    my ($hd) = @_;
    my $last = $hd->{primary}{extended} or return;
    @{$hd->{extended}} = grep {
	if ($_->{normal}) {
	    $last = $_;
	} else {
	    %{$last->{extended}} = $_->{extended} ? %{$_->{extended}} : ();
	}
	$_->{normal};
    } @{$hd->{extended}};
    adjust_main_extended($hd);
}

sub adjust_main_extended {
    my ($hd) = @_;

    if (!is_empty_array_ref $hd->{extended}) {
	my ($l, @l) = @{$hd->{extended}};

	# the first is a special case, must recompute its real size
	my $start = round_down($l->{normal}{start} - 1, $hd->{geom}{sectors});
	my $end = $l->{normal}{start} + $l->{normal}{size};
	my $only_linux = 1; my $has_win_lba = 0;
	foreach (map $_->{normal}, $l, @l) {
	    $start = min($start, $_->{start});
	    $end = max($end, $_->{start} + $_->{size});
	    $only_linux &&= isTrueFS($_) || isSwap($_);
	    $has_win_lba ||= $_->{type} == 0xc || $_->{type} == 0xe;
	}
	$l->{start} = $hd->{primary}{extended}{start} = $start;
	$l->{size} = $hd->{primary}{extended}{size} = $end - $start;
    }
    unless (@{$hd->{extended} || []} || !$hd->{primary}{extended}) {
	%{$hd->{primary}{extended}} = (); #- modify the raw entry
	delete $hd->{primary}{extended};
    }
    verifyParts($hd); #- verify everything is all right
}

sub adjust_local_extended {
    my ($hd, $part) = @_;
    
    foreach (@{$hd->{extended} || []}) {
	$_->{normal} == $part or next;
	$_->{size} = $part->{size} + $part->{start} - $_->{start};
	last;
    }
}

sub get_normal_parts {
    my ($hd) = @_;

    @{$hd->{primary}{normal} || []}, map { $_->{normal} } @{$hd->{extended} || []}
}

sub get_normal_parts_and_holes {
    my ($hd) = @_;
    my ($start, $last) = ($hd->first_usable_sector, $hd->last_usable_sector);

    ref($hd) or print("get_normal_parts_and_holes: bad hd" . backtrace(), "\n");

    my @l = map {
	my $current = $start;
	$start = $_->{start} + $_->{size};
	my $hole = { start => $current, size => $_->{start} - $current, type => 0, rootDevice => $hd->{device} };
	$hole, $_;
    } sort { $a->{start} <=> $b->{start} } grep { !isWholedisk($_) } get_normal_parts($hd);

    push @l, { start => $start, size => $last - $start, type => 0, rootDevice => $hd->{device} };
    grep { $_->{type} || $_->{size} >= $hd->cylinder_size } @l;
}

sub read_one($$) {
    my ($hd, $sector) = @_;
    my ($pt, $info);

    #- it can be safely considered that the first sector is used to probe the partition table
    #- but other sectors (typically for extended partition ones) have to match this type!
    if (!$sector) {
	my @parttype = (
	  if_(arch() =~ /^ia64/, 'gpt'),
	  arch() =~ /^sparc/ ? ('sun', 'bsd') : ('dos', 'bsd', 'sun', 'mac'),
	);
	foreach ('empty', @parttype, 'lvm_PV', 'unknown') {
	    /unknown/ and die "unknown partition table format on disk " . $hd->{file};
	    eval {
		require("partition_table/$_.pm");
		bless $hd, "partition_table::$_";
		($pt, $info) = $hd->read($sector);
		log::l("found a $_ partition table on $hd->{file} at sector $sector");
	    };
	    $@ or last;
	}
    } else {
	#- keep current blessed object for that, this means it is neccessary to read sector 0 before.
	($pt, $info) = $hd->read($sector);
    }

    my @extended = $hd->hasExtended ? grep { isExtended($_) } @$pt : ();
    my @normal = grep { $_->{size} && $_->{type} && !isExtended($_) } @$pt;

    @extended > 1 and die "more than one extended partition";

    $_->{rootDevice} = $hd->{device} foreach @normal, @extended;
    { raw => $pt, extended => $extended[0], normal => \@normal, info => $info };
}

sub read {
    my ($hd) = @_;
    my $pt = read_one($hd, 0) or return 0;
    $hd->{primary} = $pt;
    undef $hd->{extended};
    verifyPrimary($pt);
    eval {
	my $need_removing_empty_extended;
	$pt->{extended} and read_extended($hd, $pt->{extended}, \$need_removing_empty_extended) || return 0;

	if ($need_removing_empty_extended) {
	    #- special case when hda5 is empty, it must be skipped
	    #- (windows XP generates such partition tables)
	    remove_empty_extended($hd); #- includes adjust_main_extended
	}
	
    }; 
    die "extended partition: $@" if $@;

    assign_device_numbers($hd);
    remove_empty_extended($hd);
    1;
}

sub read_extended {
    my ($hd, $extended, $need_removing_empty_extended) = @_;

    my $pt = read_one($hd, $extended->{start}) or return 0;
    $pt = { %$extended, %$pt };

    push @{$hd->{extended}}, $pt;
    @{$hd->{extended}} > 100 and die "oops, seems like we're looping here :(  (or you have more than 100 extended partitions!)";

    if (@{$pt->{normal}} == 0) {
	$$need_removing_empty_extended = 1;
	delete $pt->{normal};
	print "need_removing_empty_extended\n";
    } elsif (@{$pt->{normal}} > 1) {
	die "more than one normal partition in extended partition";
    } else {
	$pt->{normal} = $pt->{normal}[0];
	#- in case of extended partitions, the start sector is local to the partition or to the first extended_part!
	$pt->{normal}{start} += $pt->{start};

	#- the following verification can broke an existing partition table that is
	#- correctly read by fdisk or cfdisk. maybe the extended partition can be
	#- recomputed to get correct size.
	if (!verifyInside($pt->{normal}, $extended)) {
	    $extended->{size} = $pt->{normal}{start} + $pt->{normal}{size};
	    verifyInside($pt->{normal}, $extended) or die "partition $pt->{normal}{device} is not inside its extended partition";
	}
    }

    if ($pt->{extended}) {
	$pt->{extended}{start} += $hd->{primary}{extended}{start};
	return read_extended($hd, $pt->{extended}, $need_removing_empty_extended);
    } else {
	1;
    }
}

# write the partition table
sub write {
    my ($hd) = @_;
    $hd->{isDirty} or return;
    $hd->{readonly} and die "a read-only partition table should not be dirty!";

    #- set first primary partition active if no primary partitions are marked as active.
    if (my @l = @{$hd->{primary}{raw}}) {
	foreach (@l) { 
	    $_->{local_start} = $_->{start}; 
	    $_->{active} ||= 0;
	}
	$l[0]{active} = 0x80 if !grep { $_->{active} } @l;
    }

    #- last chance for verification, this make sure if an error is detected,
    #- it will never be writed back on partition table.
    verifyParts($hd);

    $hd->write(0, $hd->{primary}{raw}, $hd->{primary}{info}) or die "writing of partition table failed";

    #- should be fixed but a extended exist with no real extended partition, that blanks mbr!
    if (arch() !~ /^sparc/) {
	foreach (@{$hd->{extended}}) {
	    # in case of extended partitions, the start sector must be local to the partition
	    $_->{normal}{local_start} = $_->{normal}{start} - $_->{start};
	    $_->{extended} and $_->{extended}{local_start} = $_->{extended}{start} - $hd->{primary}{extended}{start};

	    $hd->write($_->{start}, $_->{raw}) or die "writing of partition table failed";
	}
    }
    $hd->{isDirty} = 0;
    $hd->{hasBeenDirty} = 1; #- used in undo (to know if undo should believe isDirty or not)

    if ($hd->{needKernelReread} && ref($hd->{needKernelReread}) eq 'ARRAY' && $::isStandalone) {
	#- we've only been adding partitions. Try special add_partition (using BLKPG_ADD_PARTITION)
	local *F;
	partition_table::raw::openit($hd, *F) or goto force_reread;

	foreach (@{$hd->{needKernelReread}}) {
	    c::add_partition(fileno F, $_->{start}, $_->{size}, $_->{device} =~ /(\d+)$/)
		or goto force_reread;
	}
    } elsif ($hd->{needKernelReread}) {
      force_reread:
	#- now sync disk and re-read the partition table
	common::sync();

	my @magic_parts = grep { $_->{isMounted} && $_->{real_mntpoint} } get_normal_parts($hd);
	foreach (@magic_parts) {
	    syscall_('umount', $_->{real_mntpoint}) or log::l(_("error unmounting %s: %s", $_->{real_mntpoint}, "$!"));
	}
	$hd->kernel_read;
	foreach (@magic_parts) {
	    syscall_('mount', , $_->{real_mntpoint}, type2fs($_), c::MS_MGC_VAL()) or log::l(_("mount failed: ") . "$!");
	}
    }
    $hd->{needKernelReread} = 0;
}

sub active {
    my ($hd, $part) = @_;

    $_->{active} = 0 foreach @{$hd->{primary}{normal}};
    $part->{active} = 0x80;
    $hd->{isDirty} = 1;
}


# remove a normal partition from hard drive hd
sub remove {
    my ($hd, $part) = @_;
    my $i;

    #- first search it in the primary partitions
    $i = 0; foreach (@{$hd->{primary}{normal}}) {
	if ($_ eq $part) {
	    splice(@{$hd->{primary}{normal}}, $i, 1);
	    %$_ = (); #- blank it

	    $hd->raw_removed($hd->{primary}{raw});
	    return $hd->{isDirty} = $hd->{needKernelReread} = 1;
	}
	$i++;
    }

    my ($first, $second, $third) = map { $_->{normal} } @{$hd->{extended} || []};
    if ($third && $first eq $part) {
	die "Can't handle removing hda5 when hda6 is not the second partition" if $second->{start} > $third->{start};
    }      

    #- otherwise search it in extended partitions
    foreach (@{$hd->{extended} || []}) {
	$_->{normal} eq $part or next;

	delete $_->{normal}; #- remove it
	remove_empty_extended($hd);
	assign_device_numbers($hd);

	return $hd->{isDirty} = $hd->{needKernelReread} = 1;
    }
    0;
}

# create of partition at starting at `start', of size `size' and of type `type' (nice comment, uh?)
sub add_primary {
    my ($hd, $part) = @_;

    {
	local $hd->{primary}{normal}; #- save it to fake an addition of $part, that way add_primary do not modify $hd if it fails
	push @{$hd->{primary}{normal}}, $part;
	adjust_main_extended($hd); #- verify
	$hd->raw_add($hd->{primary}{raw}, $part);
    }
    push @{$hd->{primary}{normal}}, $part; #- really do it
}

sub add_extended {
    arch() =~ /^sparc|ppc/ and die _("Extended partition not supported on this platform");

    my ($hd, $part, $extended_type) = @_;
    $extended_type =~ s/Extended_?//;

    my $e = $hd->{primary}{extended};

    if ($e && !verifyInside($part, $e)) {
	#-die "sorry, can't add outside the main extended partition" unless $::unsafe;
	my $end = $e->{start} + $e->{size};
	my $start = min($e->{start}, $part->{start});
	$end = max($end, $part->{start} + $part->{size}) - $start;

	{ #- faking a resizing of the main extended partition to test for problems
	    local $e->{start} = $start;
	    local $e->{size} = $end - $start;
	    eval { verifyPrimary($hd->{primary}) };
	    $@ and die
_("You have a hole in your partition table but I can't use it.
The only solution is to move your primary partitions to have the hole next to the extended partitions.");
	}
    }

    if ($e && $part->{start} < $e->{start}) {
	my $l = first (@{$hd->{extended}});

	#- the first is a special case, must recompute its real size
	$l->{start} = round_down($l->{normal}{start} - 1, $hd->cylinder_size());
	$l->{size} = $l->{normal}{start} + $l->{normal}{size} - $l->{start};
	my $ext = { %$l };
	unshift @{$hd->{extended}}, { type => 5, raw => [ $part, $ext, {}, {} ], normal => $part, extended => $ext };
	#- size will be autocalculated :)
    } else {
	my ($ext, $ext_size) = is_empty_array_ref($hd->{extended}) ?
	  ($hd->{primary}, -1) : #- -1 size will be computed by adjust_main_extended
	  (top(@{$hd->{extended}}), $part->{size});
	my %ext = (type => $extended_type || 5, start => $part->{start}, size => $ext_size);

	$hd->raw_add($ext->{raw}, \%ext);
	$ext->{extended} = \%ext;
	push @{$hd->{extended}}, { %ext, raw => [ $part, {}, {}, {} ], normal => $part };
    }
    $part->{start}++; $part->{size}--; #- let it start after the extended partition sector
    adjustStartAndEnd($hd, $part);

    adjust_main_extended($hd);
}

sub add {
    my ($hd, $part, $primaryOrExtended, $forceNoAdjust) = @_;

    get_normal_parts($hd) >= ($hd->{device} =~ /^rd/ ? 7 : $hd->{device} =~ /^(sd|ida|cciss|ataraid)/ ? 15 : 63) and cdie "maximum number of partitions handled by linux reached";

    $part->{notFormatted} = 1;
    $part->{isFormatted} = 0;
    $part->{rootDevice} = $hd->{device};
    $part->{start} ||= 1 if arch() !~ /^sparc/; #- starting at sector 0 is not allowed
    adjustStartAndEnd($hd, $part) unless $forceNoAdjust;

    my $e = $hd->{primary}{extended};
    my $nb_primaries = $hd->{device} =~ /^rd/ ? 3 : 1;

    if (arch() =~ /^sparc|ppc/ ||
	$primaryOrExtended eq 'Primary' ||
	$primaryOrExtended !~ /Extended/ && @{$hd->{primary}{normal} || []} < $nb_primaries) {
	eval { add_primary($hd, $part) };
	goto success if !$@;
    }
    if ($hd->hasExtended) {
	eval { add_extended($hd, $part, $primaryOrExtended) };
	goto success if !$@;
    }
    {
	add_primary($hd, $part);
    }
  success:
    assign_device_numbers($hd);
    $hd->{isDirty} = 1;
    push @{$hd->{needKernelReread} ||= []}, $part if !$hd->{needKernelReread} || ref($hd->{needKernelReread}) eq 'ARRAY'
}

# search for the next partition
sub next {
    my ($hd, $part) = @_;

    first(
	  sort { $a->{start} <=> $b->{start} }
	  grep { $_->{start} >= $part->{start} + $part->{size} }
	  get_normal_parts($hd)
	 );
}
sub next_start {
    my ($hd, $part) = @_;
    my $next = &next($hd, $part);
    $next ? $next->{start} : $hd->{totalsectors};
}

sub load {
    my ($hd, $file, $force) = @_;

    local *F;
    open F, $file or die _("Error reading file %s", $file);

    my $h;
    {
	local $/ = "\0";
	eval <F>;
    }
    $@ and die _("Restoring from file %s failed: %s", $file, $@);

    ref $h eq 'ARRAY' or die _("Bad backup file");

    my %h; @h{@fields2save} = @$h;

    $h{totalsectors} == $hd->{totalsectors} or $force or cdie "bad totalsectors";

    #- unsure we don't modify totalsectors
    local $hd->{totalsectors};

    @{$hd}{@fields2save} = @$h;

    delete @$_{qw(isMounted isFormatted notFormatted toFormat toFormatUnsure)} foreach get_normal_parts($hd);
    $hd->{isDirty} = $hd->{needKernelReread} = 1;
}

sub save {
    my ($hd, $file) = @_;
    my @h = @{$hd}{@fields2save};
    local *F;
    require Data::Dumper;
    open F, ">$file"
      and print F Data::Dumper->Dump([\@h], ['$h']), "\0"
      or die _("Error writing to file %s", $file);
}