public void Write(int index, byte[] data)
{
if (mSector.Type != SECTOR.SectorType.FILE_NODE)
{
throw new Exception("Cannot write data to node type " + mSector.Type.ToString());
}
//load blocks
LoadBlocks();
// extend file with more sectors if needed
FILE_NODE fileSector = mSector as FILE_NODE;
int fileFileLength = Math.Max(fileSector.FileSize, index + data.Length);
VirtualBlock.ExtendBlocks(mDrive, mBlocks, fileSector.FileSize, fileFileLength);
//write data to the blocks
VirtualBlock.WriteBlockData(mDrive, mBlocks, index, data);
//wrte out data
CommitBlocks();
// write out new file size to disk
if (fileFileLength != fileSector.FileSize)
{
fileSector.FileSize = fileFileLength;
Drive.Disk.WriteSector(mNodeSector, fileSector.RawBytes);
}
}
static void TestPhysicalFileSystem()
{
SlowDisk disk = new SlowDisk(1);
disk.TurnOn();
int SECTOR_SIZE = disk.BytesPerSector;
//free sector
{
FREE_SECTOR freeWrite = new FREE_SECTOR(disk.BytesPerSector);
disk.WriteSector(0, freeWrite.RawBytes);
FREE_SECTOR freeRead = FREE_SECTOR.CreateFromBytes(disk.ReadSector(0));
CheckSectorBytes(freeWrite, freeRead);
}
//drive info
{
DRIVE_INFO driveWrite = new DRIVE_INFO(disk.BytesPerSector, 101);
disk.WriteSector(1, driveWrite.RawBytes);
DRIVE_INFO driveRead = DRIVE_INFO.CreateFromBytes(disk.ReadSector(1));
CheckSectorBytes(driveWrite, driveRead);
}
//dir node
{
DIR_NODE dirWrite = new DIR_NODE(disk.BytesPerSector, 103, "dir1", 10);
disk.WriteSector(2, dirWrite.RawBytes);
DIR_NODE dirRead = DIR_NODE.CreateFromBytes(disk.ReadSector(2));
CheckSectorBytes(dirWrite, dirRead);
}
//file node
{
FILE_NODE fileWrite = new FILE_NODE(disk.BytesPerSector, 104, "file1", 100);
disk.WriteSector(3, fileWrite.RawBytes);
FILE_NODE fileRead = FILE_NODE.CreateFromBytes(disk.ReadSector(3));
CheckSectorBytes(fileWrite, fileRead);
}
//data sector
{
byte[] testData = new byte[DATA_SECTOR.MaxDataLength(disk.BytesPerSector)];
for (int i = 0; i < testData.Length; i++)
{
testData[i] = (byte)(i + 1);
}
DATA_SECTOR dataWrite = new DATA_SECTOR(disk.BytesPerSector, 105, testData);
disk.WriteSector(4, dataWrite.RawBytes);
DATA_SECTOR dataRead = DATA_SECTOR.CreateFromBytes(disk.ReadSector(4));
CheckSectorBytes(dataWrite, dataRead);
}
disk.TurnOff();
}
public static NODE CreateFromBytes(byte[] raw)
{
SectorType type = GetTypeFromBytes(raw);
NODE result = null;
if (type == SectorType.DIR_NODE)
{
result = DIR_NODE.CreateFromBytes(raw);
}
else if (type == SectorType.FILE_NODE)
{
result = FILE_NODE.CreateFromBytes(raw);
}
else
{
throw new Exception("Expected a DIR_NODE or FILE_NODE!");
}
return(result);
}
private VirtualNode CommonMake(string name, bool makeFile = true)
{
if (mSector.Type != SECTOR.SectorType.DIR_NODE)
{
throw new Exception($"Cannot create Dir/File under node type " + mSector.Type.ToString());
}
LoadChildren();
if (mChildren.ContainsKey(name))
{
throw new Exception("Name already in use!");
}
int[] nextFreeSectors = mDrive.GetNextFreeSectors(2);
int nodeAddr = nextFreeSectors[0];
int dataAddr = nextFreeSectors[1];
NODE newNode = null;
if (makeFile)
{
newNode = new FILE_NODE(mDrive.Disk.BytesPerSector, dataAddr, name, 0);
}
else
{
newNode = new DIR_NODE(mDrive.Disk.BytesPerSector, dataAddr, name, 0);
}
DATA_SECTOR dirdata = new DATA_SECTOR(mDrive.Disk.BytesPerSector, 0, null);
mDrive.Disk.WriteSector(nodeAddr, newNode.RawBytes);
mDrive.Disk.WriteSector(dataAddr, dirdata.RawBytes);
VirtualNode child = new VirtualNode(mDrive, nodeAddr, newNode, this);
mChildren[name] = child;
CommitChildren();
return(child);
}