// internal for testing internal static unsafe ImmutableArray<byte> DecodeEmbeddedPortablePdbDebugDirectoryData(AbstractMemoryBlock block) { byte[] decompressed; const int headerSize = 2 * sizeof(int); var headerReader = new BlobReader(block.Pointer, headerSize); if (headerReader.ReadUInt32() != PortablePdbVersions.DebugDirectoryEmbeddedSignature) { throw new BadImageFormatException(SR.UnexpectedEmbeddedPortablePdbDataSignature); } int decompressedSize = headerReader.ReadInt32(); try { decompressed = new byte[decompressedSize]; } catch { throw new BadImageFormatException(SR.DataTooBig); } var compressed = new ReadOnlyUnmanagedMemoryStream(block.Pointer + headerSize, block.Size - headerSize); var deflate = new DeflateStream(compressed, CompressionMode.Decompress, leaveOpen: true); if (decompressedSize > 0) { int actualLength; try { actualLength = deflate.TryReadAll(decompressed, 0, decompressed.Length); } catch (InvalidDataException e) { throw new BadImageFormatException(e.Message, e.InnerException); } if (actualLength != decompressed.Length) { throw new BadImageFormatException(SR.SizeMismatch); } } // Check that there is no more compressed data left, // in case the decompressed size specified in the header is smaller // than the actual decompressed size of the data. if (deflate.ReadByte() != -1) { throw new BadImageFormatException(SR.SizeMismatch); } return ImmutableByteArrayInterop.DangerousCreateFromUnderlyingArray(ref decompressed); }