diff options
| -rwxr-xr-x | read_object.pl | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/read_object.pl b/read_object.pl new file mode 100755 index 0000000..8360882 --- /dev/null +++ b/read_object.pl @@ -0,0 +1,53 @@ +#!/usr/bin/env perl + +use Compress::Zlib; +use Digest::SHA qw(sha1_hex); +use File::Basename; +use Data::Dumper; + +use strict; +use warnings; + +my @filedata = <>; +my ($signature, $type, $size, $data) = read_object(join('', @filedata)); +my $out = format_object($type, $data); + +print "signature: $signature\ntype: $type\nsize: $size\n" + . ("-" x 40) . "\n$out\n"; + +sub read_object { + my ($zlib_data) = @_; + + my $raw_data = uncompress($zlib_data) + || die "Couldn't uncompress zlib data."; + my $sig = sha1_hex($raw_data); + $raw_data =~ /(.*?) (.*?)\0(.*)/s || die "Invalid object format."; + + my ($type, $size, $data) = ($1, $2, $3); + warn "Size mismatch: got $size, but was actually " . length($data) + unless length($data) == $size; + + ($sig, $type, $size, $data); +} + +sub format_object { + my ($type, $obj) = @_; + + if ($type eq 'commit') { + $obj; + } elsif ($type eq 'tag') { + warn 'TODO - unimplemented'; + join '', map { sprintf('%02x ', $_) } unpack('C*', $obj); + } elsif ($type eq 'tree') { + warn 'TODO - unimplemented'; + join '', map { sprintf('%02x ', $_) } unpack('C*', $obj); + } elsif ($type eq 'blob') { + warn 'TODO - unimplemented'; + join '', map { sprintf('%02x ', $_) } unpack('C*', $obj); + } else { + warn "Unknown object type, showing hex representation: $type.\n"; + join '', map { sprintf('%02x', $_) } unpack('C*', $obj); + } +} + +1; |