package Git::PurePerl::PackIndex::Version2;
use Moose;
use MooseX::StrictConstructor;
use namespace::autoclean;
extends 'Git::PurePerl::PackIndex';
my $FanOutCount = 256;
my $SHA1Size = 20;
my $IdxOffsetSize = 4;
my $OffsetSize = 4;
my $CrcSize = 4;
my $OffsetStart = $FanOutCount * $IdxOffsetSize;
my $SHA1Start = $OffsetStart + $OffsetSize;
my $EntrySize = $OffsetSize + $SHA1Size;
my $EntrySizeV2 = $SHA1Size + $CrcSize + $OffsetSize;
sub global_offset {
return 8;
}
sub all_sha1s {
my ( $self, $want_sha1 ) = @_;
my $fh = $self->fh;
my @sha1s;
my @data;
my $pos = $OffsetStart;
$fh->seek( $pos + $self->global_offset, 0 ) || die $!;
foreach my $i ( 0 .. $self->size - 1 ) {
$fh->read( my $sha1, $SHA1Size ) || die $!;
$data[$i] = [ unpack( 'H*', $sha1 ), 0, 0 ];
$pos += $SHA1Size;
}
$fh->seek( $pos + $self->global_offset, 0 ) || die $!;
foreach my $i ( 0 .. $self->size - 1 ) {
$fh->read( my $crc, $CrcSize ) || die $!;
$data[$i]->[1] = unpack( 'H*', $crc );
$pos += $CrcSize;
}
$fh->seek( $pos + $self->global_offset, 0 ) || die $!;
foreach my $i ( 0 .. $self->size - 1 ) {
$fh->read( my $offset, $OffsetSize ) || die $!;
$data[$i]->[2] = unpack( 'N', $offset );
$pos += $OffsetSize;
}
foreach my $data (@data) {
my ( $sha1, $crc, $offset ) = @$data;
push @sha1s, $sha1;
}
return @sha1s;
}
sub get_object_offset {
my ( $self, $want_sha1 ) = @_;
my @offsets = $self->offsets;
my $fh = $self->fh;
my $slot = unpack( 'C', pack( 'H*', $want_sha1 ) );
return unless defined $slot;
my ( $first, $last ) = @offsets[ $slot, $slot + 1 ];
while ( $first < $last ) {
my $mid = int( ( $first + $last ) / 2 );
$fh->seek( $self->global_offset + $OffsetStart + ( $mid * $SHA1Size ),
0 )
|| die $!;
$fh->read( my $data, $SHA1Size ) || die $!;
my $midsha1 = unpack( 'H*', $data );
if ( $midsha1 lt $want_sha1 ) {
$first = $mid + 1;
} elsif ( $midsha1 gt $want_sha1 ) {
$last = $mid;
} else {
my $pos
= $self->global_offset
+ $OffsetStart
+ ( $self->size * ( $SHA1Size + $CrcSize ) )
+ ( $mid * $OffsetSize );
$fh->seek( $pos, 0 ) || die $!;
$fh->read( my $data, $OffsetSize ) || die $!;
my $offset = unpack( 'N', $data );
return $offset;
}
}
return;
}
__PACKAGE__->meta->make_immutable;