internal static byte[] GetBytes(FileStream streamToRead, Superblock superblock, uint offset)
{
// Derive Length of Inode Table from superblock values
uint length = superblock.InodesPerGroup * Inode.EXT4_INODE_SIZE;
// Get Inode Table bytes
return(NativeMethods.readDrive(streamToRead, offset, length));
}
public byte[] GetBytes(string volume)
{
IntPtr hDevice = NativeMethods.getHandle(volume);
using (FileStream streamToRead = NativeMethods.getFileStream(hDevice))
{
Superblock sb = new Superblock(Superblock.GetBytes(streamToRead, 0));
return(NativeMethods.readDrive(streamToRead, (sb.BlockSize * this.StartBlock), (sb.BlockSize * this.BlockCount)));
}
}
internal static byte[] GetBytes(FileStream streamToRead, uint superblockOffset, Superblock superBlock, uint group)
{
// Derive the location and length of the Block Group Descriptor Table
uint bgdtOffset = (superblockOffset * NativeMethods.BYTES_PER_SECTOR) + ((superBlock.FirstDataBlock + 1) * superBlock.BlockSize);
uint bgdtEntries = (superBlock.TotalBlockCount / superBlock.BlocksPerGroup) + 1;
uint bgdtLength = bgdtEntries * BlockGroupDescriptor.BLOCK_GROUP_DESCRIPTOR_LENGTH;
// Determine the offset from the beginning of the BGDT to the desired group
uint groupOffset = group * BLOCK_GROUP_DESCRIPTOR_LENGTH;
// Determine what Sector contains the raw bytes
uint groupSectorOffset = groupOffset / NativeMethods.BYTES_PER_SECTOR;
// Read the sector that the desired block resides within
byte[] SectorBytes = NativeMethods.readDrive(streamToRead, bgdtOffset + (groupSectorOffset * NativeMethods.BYTES_PER_SECTOR), NativeMethods.BYTES_PER_SECTOR);
// Get Block Group Descriptor offset into Sector
uint sectorOffset = (group % BLOCK_GROUPS_PER_SECTOR) * BLOCK_GROUP_DESCRIPTOR_LENGTH;
// Create byte[] containing only bytes for the requested Block Group Descriptor
return(NativeMethods.GetSubArray(SectorBytes, sectorOffset, BLOCK_GROUP_DESCRIPTOR_LENGTH));
}
internal static byte[] GetBytes(FileStream streamToRead, uint superblockOffset, Superblock superBlock)
{
// Derive the location and length of the Block Group Descriptor Table
uint offset = (superblockOffset * NativeMethods.BYTES_PER_SECTOR) + ((superBlock.FirstDataBlock + 1) * superBlock.BlockSize);
uint bgdtEntries = (superBlock.TotalBlockCount / superBlock.BlocksPerGroup) + 1;
uint length = bgdtEntries * BlockGroupDescriptor.BLOCK_GROUP_DESCRIPTOR_LENGTH;
// Ensure the bgdtLength value is a multiple of 512 (minimum value for reading bytes from disk)
if ((length % NativeMethods.BYTES_PER_SECTOR) != 0)
{
length += (NativeMethods.BYTES_PER_SECTOR - (length % NativeMethods.BYTES_PER_SECTOR));
}
// Get BlockGroupDescriptor bytes
return(NativeMethods.readDrive(streamToRead, offset, length));
}
