internal SectorPtr ToSectorPtr() { SectorPtr result; result.Ptr = Position; if (Position > 0) { result.Ptr |= (uint)(Length / KeyValueDB.AllocationGranularity - 1); } result.Checksum = Dirty ? 0 : Checksum.CalcFletcher32(Data, 0, (uint)Length); return(result); }
void WriteOneBlock(ByteBuffer block, BlockType blockType) { var blockLen = (uint)block.Length; var o = block.Offset - 4; PackUnpack.PackUInt32LE(block.Buffer, o, (blockLen << 8) + (uint)blockType); var checksum = Checksum.CalcFletcher32(block.Buffer, (uint)o, blockLen + 4); o -= 4; PackUnpack.PackUInt32LE(block.Buffer, o, checksum); o -= (int)EndBufferLen; Array.Copy(EndBuffer, 0, block.Buffer, o, EndBufferLen); var lenWithoutEndPadding = (int)(EndBufferLen + HeaderSize + blockLen); block = ByteBuffer.NewAsync(block.Buffer, o, (int)((uint)(lenWithoutEndPadding + SectorSize - 1) & SectorMaskUInt)); File.Write(block, EndBufferPosition); NextReadPosition = EndBufferPosition + (ulong)lenWithoutEndPadding; EndBufferPosition = NextReadPosition & SectorMask; EndBufferLen = (uint)(NextReadPosition - EndBufferPosition); Array.Copy(block.Buffer, block.Offset + lenWithoutEndPadding - EndBufferLen, EndBuffer, 0, EndBufferLen); }
public void ReadToEnd(IEventStoreObserver observer) { var overflowWriter = default(ByteBufferWriter); var bufferBlock = new byte[FirstReadAhead + MaxBlockSize]; var bufferStartPosition = NextReadPosition & SectorMask; var bufferFullLength = 0; var bufferReadOffset = (int)(NextReadPosition - bufferStartPosition); var currentReadAhead = FirstReadAhead; var buf = ByteBuffer.NewSync(bufferBlock, bufferFullLength, currentReadAhead); var bufReadLength = (int)File.Read(buf, bufferStartPosition); bufferFullLength += bufReadLength; while (true) { if (bufferStartPosition + (ulong)bufferReadOffset + HeaderSize > File.MaxFileSize) { KnownAsFinished = true; return; } if (bufferReadOffset == bufferFullLength) { break; } if (bufferReadOffset + HeaderSize > bufferFullLength) { for (var i = bufferReadOffset; i < bufferFullLength; i++) { if (bufferBlock[i] != 0) { SetCorrupted(); return; } } break; } var blockCheckSum = PackUnpack.UnpackUInt32LE(bufferBlock, bufferReadOffset); bufferReadOffset += 4; var blockLen = PackUnpack.UnpackUInt32LE(bufferBlock, bufferReadOffset); if (blockCheckSum == 0 && blockLen == 0) { bufferReadOffset -= 4; break; } var blockType = (BlockType)(blockLen & 0xff); blockLen >>= 8; if (blockType == BlockType.LastBlock && blockLen == 0) { if (Checksum.CalcFletcher32(bufferBlock, (uint)bufferReadOffset, 4) != blockCheckSum) { SetCorrupted(); return; } KnownAsFinished = true; return; } if (blockLen == 0 && blockType != (BlockType.FirstBlock | BlockType.LastBlock)) { SetCorrupted(); return; } if (blockLen + HeaderSize > MaxBlockSize) { SetCorrupted(); return; } bufferReadOffset += 4; var bufferLenToFill = (uint)(bufferReadOffset + (int)blockLen + FirstReadAhead) & SectorMaskUInt; if (bufferLenToFill > bufferBlock.Length) { bufferLenToFill = (uint)bufferBlock.Length; } buf = ByteBuffer.NewSync(bufferBlock, bufferFullLength, (int)(bufferLenToFill - bufferFullLength)); if (buf.Length > 0) { bufferLenToFill = (uint)(bufferReadOffset + (int)blockLen + currentReadAhead) & SectorMaskUInt; if (bufferLenToFill > bufferBlock.Length) { bufferLenToFill = (uint)bufferBlock.Length; } if (bufferStartPosition + bufferLenToFill > File.MaxFileSize) { bufferLenToFill = (uint)(File.MaxFileSize - bufferStartPosition); } buf = ByteBuffer.NewSync(bufferBlock, bufferFullLength, (int)(bufferLenToFill - bufferFullLength)); if (buf.Length > 0) { if (currentReadAhead * 4 < MaxBlockSize) { currentReadAhead = currentReadAhead * 2; } bufReadLength = (int)File.Read(buf, bufferStartPosition + (ulong)bufferFullLength); bufferFullLength += bufReadLength; } } if (bufferReadOffset + (int)blockLen > bufferFullLength) { SetCorrupted(); return; } if (Checksum.CalcFletcher32(bufferBlock, (uint)bufferReadOffset - 4, blockLen + 4) != blockCheckSum) { SetCorrupted(); return; } var blockTypeBlock = blockType & (BlockType.FirstBlock | BlockType.MiddleBlock | BlockType.LastBlock); var stopReadingRequested = false; if (blockTypeBlock == (BlockType.FirstBlock | BlockType.LastBlock)) { stopReadingRequested = Process(blockType, ByteBuffer.NewSync(bufferBlock, bufferReadOffset, (int)blockLen), observer); } else { if (blockTypeBlock == BlockType.FirstBlock) { overflowWriter = new ByteBufferWriter(); } else if (blockTypeBlock == BlockType.MiddleBlock || blockTypeBlock == BlockType.LastBlock) { if (overflowWriter == null) { SetCorrupted(); return; } } else { SetCorrupted(); return; } overflowWriter.WriteBlock(ByteBuffer.NewSync(bufferBlock, bufferReadOffset, (int)blockLen)); if (blockTypeBlock == BlockType.LastBlock) { stopReadingRequested = Process(blockType, overflowWriter.Data, observer); overflowWriter = null; } } bufferReadOffset += (int)blockLen; if (overflowWriter == null) { NextReadPosition = bufferStartPosition + (ulong)bufferReadOffset; } if (stopReadingRequested) { return; } var nextBufferStartPosition = (bufferStartPosition + (ulong)bufferReadOffset) & SectorMask; var bufferMoveDistance = (int)(nextBufferStartPosition - bufferStartPosition); if (bufferMoveDistance <= 0) { continue; } Array.Copy(bufferBlock, bufferMoveDistance, bufferBlock, 0, bufferFullLength - bufferMoveDistance); bufferStartPosition = nextBufferStartPosition; bufferFullLength -= bufferMoveDistance; bufferReadOffset -= bufferMoveDistance; } if (overflowWriter != null) { // It is not corrupted here just unfinished, but definitely not appendable EndBufferPosition = ulong.MaxValue; return; } EndBufferLen = (uint)(bufferReadOffset - (bufferReadOffset & SectorMaskUInt)); EndBufferPosition = bufferStartPosition + (ulong)bufferReadOffset - EndBufferLen; Array.Copy(bufferBlock, bufferReadOffset - EndBufferLen, EndBuffer, 0, EndBufferLen); }