electron/shell/browser/net/node_stream_loader.h
Heilig Benedek 3f49f984e6 fix: race condition in NodeStreamLoader (#19811)
* fix: race condition in NodeStreamLoader

* nit: add comments
2019-08-21 12:23:46 +09:00

95 lines
3.1 KiB
C++

// Copyright (c) 2019 GitHub, Inc.
// Use of this source code is governed by the MIT license that can be
// found in the LICENSE file.
#ifndef SHELL_BROWSER_NET_NODE_STREAM_LOADER_H_
#define SHELL_BROWSER_NET_NODE_STREAM_LOADER_H_
#include <map>
#include <memory>
#include <string>
#include <vector>
#include "mojo/public/cpp/bindings/strong_binding.h"
#include "mojo/public/cpp/system/data_pipe_producer.h"
#include "services/network/public/mojom/url_loader.mojom.h"
#include "v8/include/v8.h"
namespace electron {
// Read data from node Stream and feed it to NetworkService.
//
// This class manages its own lifetime and should delete itself when the
// connection is lost or finished.
//
// We use |paused mode| to read data from |Readable| stream, so we don't need to
// copy data from buffer and hold it in memory, and we only need to make sure
// the passed |Buffer| is alive while writing data to pipe.
class NodeStreamLoader : public network::mojom::URLLoader {
public:
NodeStreamLoader(network::ResourceResponseHead head,
network::mojom::URLLoaderRequest loader,
network::mojom::URLLoaderClientPtr client,
v8::Isolate* isolate,
v8::Local<v8::Object> emitter);
private:
~NodeStreamLoader() override;
using EventCallback = base::RepeatingCallback<void()>;
void Start(network::ResourceResponseHead head);
void NotifyReadable();
void NotifyComplete(int result);
void ReadMore();
void DidWrite(MojoResult result);
// Subscribe to events of |emitter|.
void On(const char* event, EventCallback callback);
// URLLoader:
void FollowRedirect(const std::vector<std::string>& removed_headers,
const net::HttpRequestHeaders& modified_headers,
const base::Optional<GURL>& new_url) override {}
void SetPriority(net::RequestPriority priority,
int32_t intra_priority_value) override {}
void PauseReadingBodyFromNet() override {}
void ResumeReadingBodyFromNet() override {}
mojo::Binding<network::mojom::URLLoader> binding_;
network::mojom::URLLoaderClientPtr client_;
v8::Isolate* isolate_;
v8::Global<v8::Object> emitter_;
v8::Global<v8::Value> buffer_;
// Mojo data pipe where the data that is being read is written to.
std::unique_ptr<mojo::DataPipeProducer> producer_;
// Whether we are in the middle of write.
bool is_writing_ = false;
// Whether we are in the middle of a stream.read().
bool is_reading_ = false;
// When NotifyComplete is called while writing, we will save the result and
// quit with it after the write is done.
bool ended_ = false;
int result_ = net::OK;
// When the stream emits the readable event, we only want to start reading
// data if the stream was not readable before, so we store the state in a
// flag.
bool readable_ = false;
// Store the V8 callbacks to unsubscribe them later.
std::map<std::string, v8::Global<v8::Value>> handlers_;
base::WeakPtrFactory<NodeStreamLoader> weak_factory_;
DISALLOW_COPY_AND_ASSIGN(NodeStreamLoader);
};
} // namespace electron
#endif // SHELL_BROWSER_NET_NODE_STREAM_LOADER_H_