protected PackedObjectReader(PackFile packFile, long objectOffset, long dataOffset, long size, ObjectType type)
: base(type, size)
{
this.PackFile = packFile;
this.ObjectOffset = objectOffset;
this.DataOffset = dataOffset;
}
protected DeltaPackedObjectReader(PackFile packFile, long objectOffset, long dataOffset, long size, PackedObjectReader baseReader)
: base(packFile, objectOffset, dataOffset, size, ObjectType.Undefined)
{
this.Base = baseReader;
this.RawSize = size;
_type = this.Base.Type;
}
public static PackedObjectReader Create(PackFile packFile, long objectOffset)
{
using (var file = File.OpenRead(packFile.Location))
{
file.Seek(objectOffset, SeekOrigin.Begin);
var b = file.ReadByte();
var typeCode = (b & 0x70) >> 4;
var type = (ObjectType)typeCode;
var size = b & 0xF;
var bits = 4;
while ((b & 0x80) == 0x80)
{
b = file.ReadByte();
size += (b & 0x7f) << bits;
bits += 7;
}
switch (type)
{
case ObjectType.Blob:
case ObjectType.Commit:
case ObjectType.Tag:
case ObjectType.Tree:
return new WholePackedObjectReader(packFile, objectOffset, file.Position, size, type);
case ObjectType.OffsetDelta:
var baseOffset = objectOffset - file.Read7BitEncodedInt();
return new DeltaOffsetPackedObjectReader(packFile, objectOffset, file.Position, size, baseOffset);
case ObjectType.ReferenceDelta:
var baseId = file.ReadId();
return new DeltaReferencePackedObjectReader(packFile, objectOffset, file.Position, size, baseId);
case ObjectType.Undefined:
throw new InvalidDataException("ObjectType was undefined.");
case ObjectType.Reserved:
throw new InvalidDataException("ObjectType is reserved.");
default:
throw new InvalidDataException("ObjectType is not valid.");
}
}
}
public WholePackedObjectReader(PackFile packFile, long objectOffset, long dataOffset, int size, ObjectType type)
: base(packFile, objectOffset, dataOffset, size, type)
{
}