public VirtualBlock(VirtualDrive drive, int sectorAddress, DATA_SECTOR sector, bool dirty = false)
{
this.drive = drive;
this.sector = sector;
this.sectorAddress = sectorAddress;
this.dirty = dirty;
}
public VirtualDrive(DiskDriver disk, int driveInfoSector, DRIVE_INFO sector)
{
mDisk = disk;
mDriveInfoSector = driveInfoSector;
mBytesPerDataSector = DATA_SECTOR.MaxDataLength(disk.BytesPerSector);
mSector = sector;
}
public void Format(DiskDriver disk)
{
//wipe the disk
FREE_SECTOR freeSector = new FREE_SECTOR(disk.BytesPerSector);
for (int i = 0; i < disk.SectorCount; i++)
{
disk.WriteSector(i, freeSector.RawBytes);
}
//format it
DRIVE_INFO driveInfo = new DRIVE_INFO(disk.BytesPerSector, Constants.ROOT_DIR_SECTOR);
disk.WriteSector(Constants.DRIVE_INFO_SECTOR, driveInfo.RawBytes);
DIR_NODE rootNode = new DIR_NODE(disk.BytesPerSector, Constants.ROOT_DATA_SECTOR, "/", 0);
disk.WriteSector(Constants.ROOT_DIR_SECTOR, rootNode.RawBytes);
DATA_SECTOR rootData = new DATA_SECTOR(disk.BytesPerSector, 0, new byte[1]);
disk.WriteSector(Constants.ROOT_DATA_SECTOR, rootData.RawBytes);
}
private void CommitChildren()
{
DATA_SECTOR dirData = DATA_SECTOR.CreateFromBytes(mDrive.Disk.ReadSector(mSector.FirstDataAt));
byte[] data = null;
if (mChildren.Count > 0)
{
//get data for children
data = new byte[mChildren.Count * 4];
int byteIndex = 0;
foreach (VirtualNode child in mChildren.Values)
{
//copy child address
BitConverter.GetBytes(child.mNodeSector).CopyTo(data, byteIndex);
byteIndex += 4;
}
}
//add to dirData, write back to disk
dirData.DataBytes = data;
mDrive.Disk.WriteSector(mSector.FirstDataAt, dirData.RawBytes);
//write entry count to disk
(mSector as DIR_NODE).EntryCount = mChildren.Count;
mDrive.Disk.WriteSector(mNodeSector, mSector.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 void Delete()
{
if (mParent == null)
{
throw new Exception("Cannot delete root node");
}
//we need to do cleanup if we are a dir
if (IsDirectory)
{
LoadChildren();
foreach (var child in mChildren)
{
//recursive delete call to free
child.Value.Delete();
}
}
mParent.LoadChildren();
mParent.mChildren.Remove(this.Name);
mParent.CommitChildren();
//free sector to wipe with
FREE_SECTOR freeSector = new FREE_SECTOR(mDrive.Disk.BytesPerSector);
//start at first data
int sectorIndex = mSector.FirstDataAt;
while (sectorIndex != 0)
{
//store what will be next sector...
int nextsector = 0;
//get sector
DATA_SECTOR currentSector = DATA_SECTOR.CreateFromBytes(mDrive.Disk.ReadSector(sectorIndex));
nextsector = currentSector.NextSectorAt;
//wipe sector
mDrive.Disk.WriteSector(sectorIndex, freeSector.RawBytes);
//point to next sector
sectorIndex = nextsector;
}
;
//wipe main sector
mDrive.Disk.WriteSector(mNodeSector, freeSector.RawBytes);
}
private void LoadBlocks()
{
if (mBlocks == null)
{
//make list
mBlocks = new List <VirtualBlock>();
//load all blocks into memory
int currentSector = mSector.FirstDataAt;
do
{
DATA_SECTOR dataSector = DATA_SECTOR.CreateFromBytes(mDrive.Disk.ReadSector(currentSector));
mBlocks.Add(new VirtualBlock(mDrive, currentSector, dataSector, false));
currentSector = dataSector.NextSectorAt;
}while (currentSector != 0);
}
}
public static void ExtendBlocks(VirtualDrive drive, List <VirtualBlock> blocks, int initialFileLength, int finalFileLength)
{
int initialSectorcount = BlocksNeeded(drive, initialFileLength);
int finalSectorcount = BlocksNeeded(drive, finalFileLength);
if (finalSectorcount > initialSectorcount)
{
int[] freeSectors = drive.GetNextFreeSectors(finalSectorcount - initialSectorcount);
DATA_SECTOR dataSector = blocks.Last().Sector;
foreach (int freeSector in freeSectors)
{
int currentSector = dataSector.NextSectorAt = freeSector;
dataSector = new DATA_SECTOR(drive.Disk.BytesPerSector, 0, null);
blocks.Add(new VirtualBlock(drive, currentSector, dataSector, true));
}
}
}
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);
}
private void LoadChildren()
{
if (mChildren == null)
{
mChildren = new Dictionary <string, VirtualNode>();
DATA_SECTOR dirData = DATA_SECTOR.CreateFromBytes(mDrive.Disk.ReadSector(mSector.FirstDataAt));
int nChildren = (mSector as DIR_NODE).EntryCount;
for (int i = 0; i < nChildren; i++)
{
//fetch address
int childNodeAddress = BitConverter.ToInt32(dirData.DataBytes, i * 4);
//read in child
byte[] childRaw = Drive.Disk.ReadSector(childNodeAddress);
NODE childNode = NODE.CreateFromBytes(childRaw);
//store the node as virutal node child
VirtualNode virtualNode = new VirtualNode(mDrive, childNodeAddress, childNode, this);
mChildren[virtualNode.Name] = virtualNode;
}
}
}