public static DatabaseRecord ReadFrom(byte[] buffer, int offset)
{
DatabaseRecord result = null;
if (Utilities.ToInt32BigEndian(buffer, offset + 0xC) != 0)
{
switch ((RecordType)(buffer[offset + 0x13] & 0xF))
{
case RecordType.Volume:
result = new VolumeRecord();
break;
case RecordType.Component:
result = new ComponentRecord();
break;
case RecordType.Extent:
result = new ExtentRecord();
break;
case RecordType.Disk:
result = new DiskRecord();
break;
case RecordType.DiskGroup:
result = new DiskGroupRecord();
break;
default:
throw new NotImplementedException("Unrecognized record type: " + buffer[offset + 0x13]);
}
result.DoReadFrom(buffer, offset);
}
return result;
}
private static int CompareExtentInterleaveOrder(ExtentRecord x, ExtentRecord y)
{
if (x.InterleaveOrder > y.InterleaveOrder)
{
return 1;
}
else if (x.InterleaveOrder < y.InterleaveOrder)
{
return -1;
}
return 0;
}
private SparseStream OpenExtent(ExtentRecord extent)
{
DiskRecord disk = _database.GetDisk(extent.DiskId);
DynamicDisk diskObj = _disks[new Guid(disk.DiskGuidString)];
return new SubStream(diskObj.Content, Ownership.None, (diskObj.DataOffset + extent.DiskOffsetLba) * Sizes.Sector, extent.SizeLba * Sizes.Sector);
}
private static int CompareExtentOffsets(ExtentRecord x, ExtentRecord y)
{
if (x.OffsetInVolumeLba > y.OffsetInVolumeLba)
{
return 1;
}
else if (x.OffsetInVolumeLba < y.OffsetInVolumeLba)
{
return -1;
}
return 0;
}