Пример #1
0
        private static byte[] InternalCompress(byte[] bytes, bool useHeader, CompressionImplementation compressionImplementation)
        {
            switch (compressionImplementation)
            {
            case CompressionImplementation.ManagedZLib:
                return(ManagedZLibWrapper.Compress(bytes, zLibCompressionAmount, useHeader));

            default:
                throw new ApplicationException(string.Format("Unknown compression implementation {0}", compressionImplementation));
            }
        }
Пример #2
0
        private static byte[] InternalDecompress(byte[] bytes, bool useHeader, CompressionImplementation compressionImplementation)
        {
            switch (compressionImplementation)
            {
            case CompressionImplementation.ManagedZLib:
                byte[] decompressed = null;
                try
                {
                    decompressed = ManagedZLibWrapper.Decompress(bytes, useHeader);
                }
                catch (Exception e)
                {
                    if (useHeader)
                    {
                        if (e.Message.Contains("Invalid GZip header"))
                        {
                            //we're probably trying to decompress data that has no header with the header flag. if it throws again, just let it go
                            log.WarnFormat("Tried to decompress using header and got error {0}. Attempting decompress with no header.",
                                           e.Message);
                            try
                            {
                                decompressed = ManagedZLibWrapper.Decompress(bytes, false);
                            }
                            catch (Exception e2)
                            {
                                if (e2.Message.Contains("Z_DATA_ERROR"))                                         //then the data is actually invalid; it may not be compressed at all. we'll try just returning the data as it was
                                {
                                    log.WarnFormat("Tried to decompress with no header after getting error with header and got error {0}. Returning bytes as they were.", e2.Message);
                                    decompressed = bytes;
                                }
                                else
                                {
                                    throw;
                                }
                            }
                        }
                        else
                        {
                            throw;
                        }
                    }
                    else
                    {
                        if (e.Message.Contains("Z_DATA_ERROR"))
                        {
                            //probably the inverse; tried to decompress data with a header without one.
                            log.WarnFormat("Tried to decompress with no header and got error {0}. Attempting decompress with header.",
                                           e.Message);

                            try
                            {
                                decompressed = ManagedZLibWrapper.Decompress(bytes, true);
                            }
                            catch (Exception e2)
                            {
                                if (e2.Message.Contains("Invalid GZip header"))
                                {
                                    log.WarnFormat("Tried to decompress with header after getting error with header and got error {0}. Returning byte as they were.", e2.Message);
                                    decompressed = bytes;
                                }
                                else
                                {
                                    throw;
                                }
                            }
                        }
                        else
                        {
                            throw;
                        }
                    }
                }
                return(decompressed);

            default:
                throw new ApplicationException(string.Format("Unknown compression implementation {0}", compressionImplementation));
            }
        }