/// <summary>
/// Create stream table
/// </summary>
/// <param name="storage">Owner storage</param>
public StreamTable(StorageStream stream)
{
this.stream = stream;
writer = new BinaryWriter(stream);
LoadStreamTable();
}
/// <summary>
/// Create stream table
/// </summary>
/// <param name="storage">Owner storage</param>
public StreamTable(StorageStream stream)
{
this.stream = stream;
writer = new BinaryWriter(stream);
LoadStreamTable();
}
internal void StreamChanged(StorageStreamChangeType changeType, StorageStream stream)
{
if (!SystemStreamId.IsSystemStreamId(stream.StreamId) || stream.StreamId == SystemStreamId.EmptySpace)
{
switch (changeType)
{
case StorageStreamChangeType.SegmentsAndMetadata:
if (!streamsChangedDuringTransaction.Contains(stream))
{
streamsChangedDuringTransaction.Add(stream);
}
break;
case StorageStreamChangeType.Closing:
if (streamsChangedDuringTransaction.Contains(stream))
{
streamsChangedDuringTransaction.Remove(stream);
}
openedStreams.Remove(stream.StreamId);
//e.Stream.Changed -= StorageStream_Changed;
break;
}
}
}
/// <summary>
/// Creates a storage
/// </summary>
private void CreateStorage(Stream stream)
{
this.MasterStream = new MasterStream(stream, false);
// Initialize storage metadata
Segment metadataStreamSegment = Segment.Create(0, blockSize, null);
metadataStreamSegment.Save(stream);
StorageStream metadataStream = new StorageStream(new StorageStreamMetadata(null)
{
FirstSegmentPosition = 0,
InitializedLength = blockSize - Segment.StructureSize,
Length = blockSize - Segment.StructureSize,
StreamId = SystemStreamId.StorageMetadata,
StreamTableIndex = -1
}, this);
StorageMetadata storageMetadata = new StorageMetadata("[TmStorage 1.0]"); // Set metadata again because above, stream was not specified
storageMetadata.Save(metadataStream);
metadataStream.Close();
// Initialize stream table
long streamTableSegmentSize = 1000 / ((int)blockSize / StorageStreamMetadata.StructureSize) * blockSize;
Segment streamTableSegment = Segment.Create(blockSize, streamTableSegmentSize, null);
stream.Position = metadataStreamSegment.DataAreaEnd;
streamTableSegment.Save(stream);
StorageStream streamTableStream = new StorageStream(new StorageStreamMetadata(null)
{
FirstSegmentPosition = blockSize,
InitializedLength = streamTableSegmentSize - Segment.StructureSize,
Length = streamTableSegmentSize - Segment.StructureSize,
StreamId = SystemStreamId.StreamTable,
StreamTableIndex = -1
}, this);
// Initialize empty space stream
Segment emptyStreamSegment = Segment.Create(streamTableSegment.DataAreaEnd, long.MaxValue - streamTableSegment.DataAreaEnd, null);
stream.Position = streamTableSegment.DataAreaEnd;
emptyStreamSegment.Save(stream);
// Write empty space stream metadata to stream table
StorageStreamMetadata emptySpaceStreamMetadata = new StorageStreamMetadata(streamTableStream)
{
FirstSegmentPosition = emptyStreamSegment.Location,
InitializedLength = emptyStreamSegment.DataAreaSize,
Length = emptyStreamSegment.DataAreaSize,
StreamId = SystemStreamId.EmptySpace,
StreamTableIndex = 0
};
emptySpaceStreamMetadata.Save();
this.MasterStream = null;
}
/// <summary>
/// Opens a stream
/// </summary>
/// <param name="streamId">Stream Id</param>
public StorageStream OpenStream(Guid streamId)
{
CheckClosed();
if (SystemStreamId.IsSystemStreamId(streamId))
{
throw new InvalidStreamIdException();
}
StartTransaction();
try
{
StorageStream tmpStream = null;
WeakReference <StorageStream> streamRef;
// Check if stream is already opened
if (openedStreams.TryGetValue(streamId, out streamRef))
{
if (!streamRef.TryGetTarget(out tmpStream))
{
tmpStream = null;
openedStreams.Remove(streamId);
}
}
// Open stream
if (tmpStream == null)
{
var streamMetadata = streamTable.Get(streamId);
if (streamMetadata == null)
{
throw new StreamNotFoundException();
}
tmpStream = new StorageStream(streamMetadata, this);
//tmpStream.Changed += StorageStream_Changed;
openedStreams.Add(streamId, new WeakReference <StorageStream>(tmpStream));
}
tmpStream.Position = 0;
CommitTransaction();
return(tmpStream);
}
catch
{
RollbackTransaction();
throw;
}
}
/// <summary>
/// Gets areas where specified stream segments are located
/// </summary>
public List <SegmentExtent> GetStreamExtents(Guid streamId)
{
CheckClosed();
if (SystemStreamId.IsSystemStreamId(streamId))
{
throw new InvalidStreamIdException();
}
StorageStream stream = OpenStream(streamId);
return(stream.GetStreamExtents());
}
/// <summary>
/// Deletes a stream
/// </summary>
/// <param name="streamId">Stream Id</param>
public void DeleteStream(Guid streamId)
{
CheckClosed();
if (SystemStreamId.IsSystemStreamId(streamId))
{
throw new InvalidStreamIdException();
}
StartTransaction();
try
{
// Before deleting, set stream size to zero to deallocate all of the space it occupies
StorageStream tmpStream = OpenStream(streamId);
tmpStream.SetLength(0);
tmpStream.Close();
openedStreams.Remove(streamId);
streamTable.Remove(streamId);
// Remove stream from list of changed streams
tmpStream = streamsChangedDuringTransaction.SingleOrDefault(x => x.StreamId == streamId);
if (tmpStream != null)
{
streamsChangedDuringTransaction.Remove(tmpStream);
}
// Remove stream from list of created streams
if (streamsCreatedDuringTransaction.Contains(streamId))
{
streamsCreatedDuringTransaction.Remove(streamId);
}
CommitTransaction();
}
catch
{
RollbackTransaction();
throw;
}
}
/// <summary>
/// Opens the storage
/// </summary>
private void OpenStorage()
{
StartTransaction();
try
{
// For metadata assume block size of 512 because blockSize is unknown at this point.
// 512 is the smallest block size so it will work as long as storage metadata is not
// longer than 512 bytes
storageMetadataStream = new StorageStream(new StorageStreamMetadata(null)
{
FirstSegmentPosition = 0,
InitializedLength = 512 - Segment.StructureSize,
Length = 512 - Segment.StructureSize,
StreamId = SystemStreamId.StorageMetadata,
StreamTableIndex = -1
}, this);
StorageMetadata = StorageMetadata.Load(storageMetadataStream);
streamTableStreamMetadata = new StorageStreamMetadata(storageMetadataStream)
{
FirstSegmentPosition = blockSize,
StreamId = SystemStreamId.StreamTable,
StreamTableIndex = -1
};
streamTableStream = new StorageStream(streamTableStreamMetadata, this);
streamTable = new StreamTable(streamTableStream);
var freeSpaceStreamMetadata = streamTable.Get(SystemStreamId.EmptySpace);
FreeSpaceStream = new StorageStream(freeSpaceStreamMetadata, this);
CommitTransaction();
}
catch
{
RollbackTransaction();
throw;
}
}
internal void StreamChanged(StorageStreamChangeType changeType, StorageStream stream)
{
if (!SystemStreamId.IsSystemStreamId(stream.StreamId) || stream.StreamId == SystemStreamId.EmptySpace)
{
switch (changeType)
{
case StorageStreamChangeType.SegmentsAndMetadata:
if (!streamsChangedDuringTransaction.Contains(stream))
streamsChangedDuringTransaction.Add(stream);
break;
case StorageStreamChangeType.Closing:
if (streamsChangedDuringTransaction.Contains(stream))
streamsChangedDuringTransaction.Remove(stream);
openedStreams.Remove(stream.StreamId);
//e.Stream.Changed -= StorageStream_Changed;
break;
}
}
}
/// <summary>
/// Opens the storage
/// </summary>
private void OpenStorage()
{
StartTransaction();
try
{
// For metadata assume block size of 512 because blockSize is unknown at this point.
// 512 is the smallest block size so it will work as long as storage metadata is not
// longer than 512 bytes
storageMetadataStream = new StorageStream(new StorageStreamMetadata(null)
{
FirstSegmentPosition = 0,
InitializedLength = 512 - Segment.StructureSize,
Length = 512 - Segment.StructureSize,
StreamId = SystemStreamId.StorageMetadata,
StreamTableIndex = -1
}, this);
StorageMetadata = StorageMetadata.Load(storageMetadataStream);
streamTableStreamMetadata = new StorageStreamMetadata(storageMetadataStream)
{
FirstSegmentPosition = blockSize,
StreamId = SystemStreamId.StreamTable,
StreamTableIndex = -1
};
streamTableStream = new StorageStream(streamTableStreamMetadata, this);
streamTable = new StreamTable(streamTableStream);
var freeSpaceStreamMetadata = streamTable.Get(SystemStreamId.EmptySpace);
FreeSpaceStream = new StorageStream(freeSpaceStreamMetadata, this);
CommitTransaction();
}
catch
{
RollbackTransaction();
throw;
}
}
/// <summary>
/// Creates a storage
/// </summary>
private void CreateStorage(Stream stream)
{
this.MasterStream = new MasterStream(stream, false);
// Initialize storage metadata
Segment metadataStreamSegment = Segment.Create(0, blockSize, null);
metadataStreamSegment.Save(stream);
StorageStream metadataStream = new StorageStream(new StorageStreamMetadata(null)
{
FirstSegmentPosition = 0,
InitializedLength = blockSize - Segment.StructureSize,
Length = blockSize - Segment.StructureSize,
StreamId = SystemStreamId.StorageMetadata,
StreamTableIndex = -1
}, this);
StorageMetadata storageMetadata = new StorageMetadata("[TmStorage 1.0]"); // Set metadata again because above, stream was not specified
storageMetadata.Save(metadataStream);
metadataStream.Close();
// Initialize stream table
long streamTableSegmentSize = 1000 / ((int)blockSize / StorageStreamMetadata.StructureSize) * blockSize;
Segment streamTableSegment = Segment.Create(blockSize, streamTableSegmentSize, null);
stream.Position = metadataStreamSegment.DataAreaEnd;
streamTableSegment.Save(stream);
StorageStream streamTableStream = new StorageStream(new StorageStreamMetadata(null)
{
FirstSegmentPosition = blockSize,
InitializedLength = streamTableSegmentSize - Segment.StructureSize,
Length = streamTableSegmentSize - Segment.StructureSize,
StreamId = SystemStreamId.StreamTable,
StreamTableIndex = -1
}, this);
// Initialize empty space stream
Segment emptyStreamSegment = Segment.Create(streamTableSegment.DataAreaEnd, long.MaxValue - streamTableSegment.DataAreaEnd, null);
stream.Position = streamTableSegment.DataAreaEnd;
emptyStreamSegment.Save(stream);
// Write empty space stream metadata to stream table
StorageStreamMetadata emptySpaceStreamMetadata = new StorageStreamMetadata(streamTableStream)
{
FirstSegmentPosition = emptyStreamSegment.Location,
InitializedLength = emptyStreamSegment.DataAreaSize,
Length = emptyStreamSegment.DataAreaSize,
StreamId = SystemStreamId.EmptySpace,
StreamTableIndex = 0
};
emptySpaceStreamMetadata.Save();
this.MasterStream = null;
}
/// <summary>
/// Opens a stream
/// </summary>
/// <param name="streamId">Stream Id</param>
public StorageStream OpenStream(Guid streamId)
{
CheckClosed();
if (SystemStreamId.IsSystemStreamId(streamId))
throw new InvalidStreamIdException();
StartTransaction();
try
{
StorageStream tmpStream = null;
WeakReference<StorageStream> streamRef;
// Check if stream is already opened
if (openedStreams.TryGetValue(streamId, out streamRef))
{
if (!streamRef.TryGetTarget(out tmpStream))
{
tmpStream = null;
openedStreams.Remove(streamId);
}
}
// Open stream
if (tmpStream == null)
{
var streamMetadata = streamTable.Get(streamId);
if (streamMetadata == null)
throw new StreamNotFoundException();
tmpStream = new StorageStream(streamMetadata, this);
//tmpStream.Changed += StorageStream_Changed;
openedStreams.Add(streamId, new WeakReference<StorageStream>(tmpStream));
}
tmpStream.Position = 0;
CommitTransaction();
return tmpStream;
}
catch
{
RollbackTransaction();
throw;
}
}
