public VirtualNode(VirtualDrive drive, int nodeSector, NODE sector, VirtualNode parent)
{
mDrive = drive;
mNodeSector = nodeSector;
mSector = sector;
mParent = parent;
mChildren = null;
mBlocks = null;
}
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);
}
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;
}
}
}
