public void AddFirst(DataBlock block)
{
if (_firstBlock == null)
{
AddBlockToEmptyMap(block);
}
else
{
AddBeforeInternal(_firstBlock, block);
}
}
public void AddLast(DataBlock block)
{
if (_firstBlock == null)
{
AddBlockToEmptyMap(block);
}
else
{
AddAfterInternal(GetLastBlock(), block);
}
}
FileDataBlock GetNextFileDataBlock(DataBlock block, long dataOffset, out long nextDataOffset)
{
// Iterate over the remaining blocks until a file block is encountered.
nextDataOffset = dataOffset + block.Length;
block = block.NextBlock;
while (block != null)
{
FileDataBlock fileBlock = block as FileDataBlock;
if (fileBlock != null)
{
return fileBlock;
}
nextDataOffset += block.Length;
block = block.NextBlock;
}
return null;
}
public DataBlock Replace(DataBlock block, DataBlock newBlock)
{
AddAfterInternal(block, newBlock);
RemoveInternal(block);
return newBlock;
}
public void Remove(DataBlock block)
{
RemoveInternal(block);
}
public void AddAfter(DataBlock block, DataBlock newBlock)
{
AddAfterInternal(block, newBlock);
}
public void AddBefore(DataBlock block, DataBlock newBlock)
{
AddBeforeInternal(block, newBlock);
}
public bool MoveNext()
{
if (this._version != _map._version)
{
throw new InvalidOperationException("Collection was modified after the enumerator was instantiated.");
}
if (_index >= _map.Count)
{
return false;
}
if (++_index == 0)
{
_current = _map.FirstBlock;
}
else
{
_current = _current.NextBlock;
}
return (_index < _map.Count);
}
void IEnumerator.Reset()
{
if (this._version != this._map._version)
{
throw new InvalidOperationException("Collection was modified after the enumerator was instantiated.");
}
this._index = -1;
this._current = null;
}
void AddBlockToEmptyMap(DataBlock block)
{
block._map = this;
block._nextBlock = null;
block._previousBlock = null;
_firstBlock = block;
_version++;
_count++;
}
internal Enumerator(DataMap map)
{
_map = map;
_version = map._version;
_current = null;
_index = -1;
}
void InvalidateBlock(DataBlock block)
{
block._map = null;
block._nextBlock = null;
block._previousBlock = null;
}
void RemoveInternal(DataBlock block)
{
DataBlock previousBlock = block._previousBlock;
DataBlock nextBlock = block._nextBlock;
if (previousBlock != null)
{
previousBlock._nextBlock = nextBlock;
}
if (nextBlock != null)
{
nextBlock._previousBlock = previousBlock;
}
if (_firstBlock == block)
{
_firstBlock = nextBlock;
}
InvalidateBlock(block);
_count--;
_version++;
}
void AddBeforeInternal(DataBlock block, DataBlock newBlock)
{
newBlock._nextBlock = block;
newBlock._previousBlock = block._previousBlock;
newBlock._map = this;
if (block._previousBlock != null)
{
block._previousBlock._nextBlock = newBlock;
}
block._previousBlock = newBlock;
if (_firstBlock == block)
{
_firstBlock = newBlock;
}
this._version++;
this._count++;
}
void AddAfterInternal(DataBlock block, DataBlock newBlock)
{
newBlock._previousBlock = block;
newBlock._nextBlock = block._nextBlock;
newBlock._map = this;
if (block._nextBlock != null)
{
block._nextBlock._previousBlock = newBlock;
}
block._nextBlock = newBlock;
this._version++;
this._count++;
}
public void Clear()
{
DataBlock block = FirstBlock;
while (block != null)
{
DataBlock nextBlock = block.NextBlock;
InvalidateBlock(block);
block = nextBlock;
}
_firstBlock = null;
_count = 0;
_version++;
}
