| // Copyright 2014 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| part of core; |
| |
| class DataPipeDrainer { |
| MojoDataPipeConsumer _consumer; |
| MojoEventStream _eventStream; |
| List<ByteData> _dataList; |
| int _dataSize; |
| |
| DataPipeDrainer(this._consumer) { |
| _eventStream = new MojoEventStream(_consumer.handle); |
| _dataList = new List(); |
| _dataSize = 0; |
| } |
| |
| ByteData _copy(ByteData byteData) => |
| new ByteData.view( |
| new Uint8List.fromList(byteData.buffer.asUint8List()).buffer); |
| |
| MojoResult _doRead() { |
| ByteData thisRead = _consumer.beginRead(); |
| if (thisRead == null) { |
| throw 'Data pipe beginRead failed: ${_consumer.status}'; |
| } |
| _dataList.add(_copy(thisRead)); |
| _dataSize += thisRead.lengthInBytes; |
| return _consumer.endRead(thisRead.lengthInBytes); |
| } |
| |
| ByteData _concatData() { |
| var data = new ByteData(_dataSize); |
| int end = 0; |
| for (var chunk in _dataList) { |
| data.buffer.asUint8List().setRange( |
| end, end + chunk.lengthInBytes, chunk.buffer.asUint8List()); |
| end += chunk.lengthInBytes; |
| } |
| return data; |
| } |
| |
| Future<ByteData> drain() { |
| var completer = new Completer(); |
| _eventStream.listen((List<int> event) { |
| var mojoSignals = new MojoHandleSignals(event[1]); |
| if (mojoSignals.isReadable) { |
| var result = _doRead(); |
| if (!result.isOk) { |
| _eventStream.close(); |
| _eventStream = null; |
| completer.complete(_concatData()); |
| } else { |
| _eventStream.enableReadEvents(); |
| } |
| } else if (mojoSignals.isPeerClosed) { |
| _eventStream.close(); |
| _eventStream = null; |
| completer.complete(_concatData()); |
| } else { |
| throw 'Unexpected handle event: $mojoSignals'; |
| } |
| }); |
| return completer.future; |
| } |
| |
| static Future<ByteData> drainHandle(MojoDataPipeConsumer consumer) { |
| var drainer = new DataPipeDrainer(consumer); |
| return drainer.drain(); |
| } |
| } |