Initial implementation of Cronet Async API.

components/cronet/android/cronet_url_request_context_adapter.h

+// 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.
+
+#ifndef COMPONENTS_CRONET_ANDROID_CRONET_URL_REQUEST_CONTEXT_ADAPTER_H_
+#define COMPONENTS_CRONET_ANDROID_CRONET_URL_REQUEST_CONTEXT_ADAPTER_H_
+
+#include <string>
+
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/threading/thread.h"
+#include "net/base/net_log.h"
+#include "net/base/network_change_notifier.h"
+#include "net/url_request/url_request_context_getter.h"

[mmenke, 2014/10/31 15:49:22]

Not used

[mef, 2014/10/31 20:39:16]

Done.

+
+namespace base {
+class SingleThreadTaskRunner;
+}  // namespace base
+
+namespace net {
+class NetLogLogger;
+class URLRequestContext;
+}  // namespace net
+
+namespace cronet {
+
+struct URLRequestContextConfig;
+
+// Adapter between Java CronetUrlRequestContext and URLRequestContextGetter.

[mmenke, 2014/10/31 15:49:22]

URLRequestContextGetter -> URLRequestContext

[mef, 2014/10/31 20:39:16]

Done.

+class CronetURLRequestContextAdapter {
+ public:
+  CronetURLRequestContextAdapter();
+  void Initialize(scoped_ptr<URLRequestContextConfig> config,
+                  const base::Closure& init_java_network_thread);

[mmenke, 2014/10/31 15:49:22]

nit:  suggest a linebreak above and below Initialize() declaration, for
readability.

[mef, 2014/10/31 20:39:16]

Done.

+  // Releases all resources for the request context and deletes the object.
+  void Destroy();
+
+  // net::URLRequestContextGetter implementation:

[mmenke, 2014/10/31 15:49:22]

Not true.

[mef, 2014/10/31 20:39:16]

Done.

+  net::URLRequestContext* GetURLRequestContext();

[mmenke, 2014/10/31 15:49:22]

Add line break after method.

[mef, 2014/10/31 20:39:16]

Done.

+  scoped_refptr<base::SingleThreadTaskRunner>

[mmenke, 2014/10/31 15:49:23]

Maybe const scoped_refptr<>&, to avoid an extra reference count
increment/decrement at all call sites?

[mef, 2014/10/31 20:39:16]

Done.

+      GetNetworkTaskRunner() const;
+
+  void StartNetLogToFile(const std::string& file_name);
+  void StopNetLog();
+
+  virtual ~CronetURLRequestContextAdapter();

[mmenke, 2014/10/31 15:49:23]

-virtual

[mef, 2014/10/31 20:39:16]

Done.

+
+ private:
+  scoped_ptr<net::URLRequestContext> context_;

[mmenke, 2014/10/31 15:49:22]

Should mention that the context_ and logger_ may only be accessed on the network
thread.

[mmenke, 2014/10/31 15:49:23]

Context should be last, after everything it depends on.

[mef, 2014/10/31 20:39:16]

Done.

[mef, 2014/10/31 20:39:16]

Done.

+  base::Thread* network_thread_;

[mmenke, 2014/10/31 15:49:22]

Hrm...guess we can't put this into a scoped_ptr and then pop it out on destroy()
because of all the thread correctness DCHECKs.  Think we should comment on its
ownership model here.

Another option, which I think makes ownership clearer, is to split it into two
classes:  CronetURLRequestContextAdapter and CronetURLRequestContextAdaperCore
(Or something like that - that is a bit unwieldy).  Have the Core only
dereferenced on the the network thread, and the adapter only dereferenced on
Java threads.  The adapter owns the core and the thread.  For destruction, just
posts a message to delete the core to the network thread, and then deletes
itself.

Not a huge improvement, but does make ownership a bit clearer.  Even if we don't
go with that architecture now, think we may well want to go in that direction
longer term (And possibly for the request, too)

[mef, 2014/10/31 20:39:16]

Acknowledged.

+  scoped_ptr<net::NetLogLogger> net_log_logger_;
+
+  // Initializes |context_| on the Network thread.
+  void InitializeOnNetworkThread(scoped_ptr<URLRequestContextConfig> config,

[mmenke, 2014/10/31 15:49:22]

Fix indent (Either move config to the next line, or indent the other line to
align with it)

[mef, 2014/10/31 20:39:16]

Done.

+      const base::Closure& init_java_network_thread);

[mmenke, 2014/10/31 15:49:22]

Should include callback.h

[mef, 2014/10/31 20:39:16]

Done.

+  void StartNetLogToFileOnNetworkThread(const std::string& file_name);
+  void StopNetLogOnNetworkThread();
+
+  DISALLOW_COPY_AND_ASSIGN(CronetURLRequestContextAdapter);
+};
+
+}  // namespace cronet
+
+#endif  // COMPONENTS_CRONET_ANDROID_CRONET_URL_REQUEST_CONTEXT_ADAPTER_H_