1 // Copyright 2014 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef MOJO_EDK_JS_DRAIN_DATA_H_ 6 #define MOJO_EDK_JS_DRAIN_DATA_H_ 7 8 #include "base/memory/scoped_vector.h" 9 #include "gin/runner.h" 10 #include "mojo/public/cpp/system/core.h" 11 #include "mojo/public/cpp/system/watcher.h" 12 #include "v8/include/v8.h" 13 14 namespace mojo { 15 namespace edk { 16 namespace js { 17 18 // This class is the implementation of the Mojo JavaScript core module's 19 // drainData() method. It is not intended to be used directly. The caller 20 // allocates a DrainData on the heap and returns GetPromise() to JS. The 21 // implementation deletes itself after reading as much data as possible 22 // and rejecting or resolving the Promise. 23 24 class DrainData { 25 public: 26 // Starts waiting for data on the specified data pipe consumer handle. 27 // See WaitForData(). The constructor does not block. 28 DrainData(v8::Isolate* isolate, mojo::Handle handle); 29 30 // Returns a Promise that will be settled when no more data can be read. 31 // Should be called just once on a newly allocated DrainData object. 32 v8::Handle<v8::Value> GetPromise(); 33 34 private: 35 ~DrainData(); 36 37 // Waits for data to be available. DataReady() will be notified. 38 void WaitForData(); 39 40 // Use ReadData() to read whatever is availble now on handle_ and save 41 // it in data_buffers_. 42 void DataReady(MojoResult result); 43 MojoResult ReadData(); 44 45 // When the remote data pipe handle is closed, or an error occurs, deliver 46 // all of the buffered data to the JS Promise and then delete this. 47 void DeliverData(MojoResult result); 48 49 using DataBuffer = std::vector<char>; 50 51 v8::Isolate* isolate_; 52 ScopedDataPipeConsumerHandle handle_; 53 Watcher handle_watcher_; 54 base::WeakPtr<gin::Runner> runner_; 55 v8::UniquePersistent<v8::Promise::Resolver> resolver_; 56 ScopedVector<DataBuffer> data_buffers_; 57 }; 58 59 } // namespace js 60 } // namespace edk 61 } // namespace mojo 62 63 #endif // MOJO_EDK_JS_DRAIN_DATA_H_ 64
