コード例 #1
0
        public static Task Run(Options options, BackupDatabase database, ITaskReader taskreader)
        {
            return(AutomationExtensions.RunTask(
                       new
            {
                Input = Channels.StreamBlock.ForRead,
                ProgressChannel = Channels.ProgressEvents.ForWrite,
                BlockOutput = Channels.OutputBlocks.ForWrite
            },

                       async self =>
            {
                var blocksize = options.Blocksize;
                var filehasher = Duplicati.Library.Utility.HashAlgorithmHelper.Create(options.FileHashAlgorithm);
                var blockhasher = Duplicati.Library.Utility.HashAlgorithmHelper.Create(options.BlockHashAlgorithm);
                var emptymetadata = Utility.WrapMetadata(new Dictionary <string, string>(), options);
                var maxmetadatasize = (options.Blocksize / (long)options.BlockhashSize) * options.Blocksize;

                if (blockhasher == null)
                {
                    throw new UserInformationException(Strings.Common.InvalidHashAlgorithm(options.BlockHashAlgorithm), "BlockHashAlgorithmNotSupported");
                }
                if (filehasher == null)
                {
                    throw new UserInformationException(Strings.Common.InvalidHashAlgorithm(options.FileHashAlgorithm), "FileHashAlgorithmNotSupported");
                }

                if (!blockhasher.CanReuseTransform)
                {
                    throw new UserInformationException(Strings.Common.InvalidCryptoSystem(options.BlockHashAlgorithm), "BlockHashAlgorithmNotSupported");
                }
                if (!filehasher.CanReuseTransform)
                {
                    throw new UserInformationException(Strings.Common.InvalidCryptoSystem(options.FileHashAlgorithm), "FileHashAlgorithmNotSupported");
                }

                using (var empty_metadata_stream = new MemoryStream(emptymetadata.Blob))
                    while (await taskreader.ProgressAsync)
                    {
                        var send_close = false;
                        var filesize = 0L;
                        var filename = string.Empty;

                        var e = await self.Input.ReadAsync();
                        var cur = e.Result;

                        try
                        {
                            var stream = e.Stream;

                            using (var blocklisthashes = new Library.Utility.FileBackedStringList())
                                using (var hashcollector = new Library.Utility.FileBackedStringList())
                                {
                                    var blocklistbuffer = new byte[blocksize];
                                    var blocklistoffset = 0L;

                                    long fslen = -1;
                                    try { fslen = stream.Length; }
                                    catch (Exception ex) { Logging.Log.WriteWarningMessage(FILELOGTAG, "FileLengthFailure", ex, "Failed to read file length for file {0}", e.Path); }

                                    if (e.IsMetadata && fslen > maxmetadatasize)
                                    {
                                        //TODO: To fix this, the "WriteFileset" method in BackupHandler needs to
                                        // be updated such that it can select sets even when there are multiple
                                        // blocklist hashes for the metadata.
                                        // This could be done such that an extra query is made if the metadata
                                        // spans multiple blocklist hashes, as it is not expected to be common

                                        Logging.Log.WriteWarningMessage(LOGTAG, "TooLargeMetadata", null, "Metadata size is {0}, but the largest accepted size is {1}, recording empty metadata for {2}", fslen, maxmetadatasize, e.Path);
                                        empty_metadata_stream.Position = 0;
                                        stream = empty_metadata_stream;
                                        fslen = stream.Length;
                                    }

                                    await self.ProgressChannel.WriteAsync(new ProgressEvent()
                                    {
                                        Filepath = e.Path, Length = fslen, Type = EventType.FileStarted
                                    });
                                    send_close = true;

                                    filehasher.Initialize();
                                    var lastread = 0;
                                    var buf = new byte[blocksize];
                                    var lastupdate = DateTime.Now;

                                    // Core processing loop, read blocks of data and hash individually
                                    while (((lastread = await stream.ForceStreamReadAsync(buf, blocksize)) != 0))
                                    {
                                        // Run file hashing concurrently to squeeze a little extra concurrency out of it
                                        var pftask = Task.Run(() => filehasher.TransformBlock(buf, 0, lastread, buf, 0));

                                        var hashdata = blockhasher.ComputeHash(buf, 0, lastread);
                                        var hashkey = Convert.ToBase64String(hashdata);

                                        // If we have too many hashes, flush the blocklist
                                        if (blocklistbuffer.Length - blocklistoffset < hashdata.Length)
                                        {
                                            var blkey = Convert.ToBase64String(blockhasher.ComputeHash(blocklistbuffer, 0, (int)blocklistoffset));
                                            blocklisthashes.Add(blkey);
                                            await DataBlock.AddBlockToOutputAsync(self.BlockOutput, blkey, blocklistbuffer, 0, blocklistoffset, CompressionHint.Noncompressible, true);
                                            blocklistoffset = 0;
                                            blocklistbuffer = new byte[blocksize];
                                        }

                                        // Store the current hash in the blocklist
                                        Array.Copy(hashdata, 0, blocklistbuffer, blocklistoffset, hashdata.Length);
                                        blocklistoffset += hashdata.Length;
                                        hashcollector.Add(hashkey);
                                        filesize += lastread;

                                        // Don't spam updates
                                        if ((DateTime.Now - lastupdate).TotalSeconds > 10)
                                        {
                                            await self.ProgressChannel.WriteAsync(new ProgressEvent()
                                            {
                                                Filepath = e.Path, Length = filesize, Type = EventType.FileProgressUpdate
                                            });
                                            lastupdate = DateTime.Now;
                                        }

                                        // Make sure the filehasher is done with the buf instance before we pass it on
                                        await pftask;
                                        await DataBlock.AddBlockToOutputAsync(self.BlockOutput, hashkey, buf, 0, lastread, e.Hint, true);
                                        buf = new byte[blocksize];
                                    }

                                    // If we have more than a single block of data, output the (trailing) blocklist
                                    if (hashcollector.Count > 1)
                                    {
                                        var blkey = Convert.ToBase64String(blockhasher.ComputeHash(blocklistbuffer, 0, (int)blocklistoffset));
                                        blocklisthashes.Add(blkey);
                                        await DataBlock.AddBlockToOutputAsync(self.BlockOutput, blkey, blocklistbuffer, 0, blocklistoffset, CompressionHint.Noncompressible, true);
                                    }

                                    filehasher.TransformFinalBlock(new byte[0], 0, 0);
                                    var filehash = Convert.ToBase64String(filehasher.Hash);
                                    var blocksetid = await database.AddBlocksetAsync(filehash, filesize, blocksize, hashcollector, blocklisthashes);
                                    cur.SetResult(new StreamProcessResult()
                                    {
                                        Streamlength = filesize, Streamhash = filehash, Blocksetid = blocksetid
                                    });
                                    cur = null;
                                }
                        }
                        catch (Exception ex)
                        {
                            try
                            {
                                if (cur != null)
                                {
                                    cur.TrySetException(ex);
                                }
                            }
                            catch { }

                            // Rethrow
                            if (ex.IsRetiredException())
                            {
                                throw;
                            }
                        }
                        finally
                        {
                            if (cur != null)
                            {
                                try { cur.TrySetCanceled(); }
                                catch { }
                                cur = null;
                            }

                            if (send_close)
                            {
                                await self.ProgressChannel.WriteAsync(new ProgressEvent()
                                {
                                    Filepath = e.Path, Length = filesize, Type = EventType.FileClosed
                                });
                            }
                            send_close = false;
                        }
                    }
            }));
        }