Adding basic implementation of AudioNetworkAdaptor.

webrtc/modules/audio_coding/audio_network_adaptor/controller_manager.h

+/*
+ *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef WEBRTC_MODULES_AUDIO_CODING_AUDIO_NETWORK_ADAPTOR_CONTROLLER_MANAGER_H_
+#define WEBRTC_MODULES_AUDIO_CODING_AUDIO_NETWORK_ADAPTOR_CONTROLLER_MANAGER_H_
+
+#include <memory>
+#include <vector>
+
+#include "webrtc/base/constructormagic.h"
+#include "webrtc/modules/audio_coding/audio_network_adaptor/controller.h"
+
+namespace webrtc {
+
+class ControllerManager {
+ public:
+  struct Config {
+    Config();
+    ~Config();
+  };
+
+  explicit ControllerManager(const Config& config);
+
+  // Dependency injection for testing.
+  ControllerManager(const Config& config,
+                    std::vector<std::unique_ptr<Controller>> controllers);
+
+  virtual ~ControllerManager();
+
+  // Sort controllers based on their significance.
+  virtual std::vector<Controller*> GetSortedControllers(
+      const Controller::NetworkMetrics& metrics);
+
+  virtual std::vector<Controller*> GetControllers() const;
+
+ private:
+  const Config config_;
+
+  std::vector<std::unique_ptr<Controller>> controllers_;
+
+  std::vector<Controller*> default_sorted_controllers_;
+
+  RTC_DISALLOW_COPY_AND_ASSIGN(ControllerManager);
+};

[kwiberg-webrtc, 2016/09/09 11:56:15]

I can't tell if this class is supposed to be an interface (in which case it
shouldn't have state) or an implementation (in which case it doesn't seem to
actually do anything; only the "dependency injection" constructor actually puts
anything in controllers_).

[minyue-webrtc, 2016/09/12 11:36:11]

Some implementations will be added in later CLs:
1. creating controllers in ControllerManager(const Config& config)
2. Sort controllers in GetSortedControllers().

[kwiberg-webrtc, 2016/09/12 13:33:50]

OK. Sounds like an implementation, then. In which case this class should either
(1) have no virtual methods, or (2) inherit from a pure virtual base class where
all the virtual methods are defined. (These aren't the only two options, but in
95% of cases one of them is the right one.)

[minyue-webrtc, 2016/09/12 15:08:35]

The need for virtual methods is due to the need of a mock controller manager.
Then I think it fits 2) better, and yes, the code becomes cleaner by introducing
an abstract ControllerManager, e.g., no need for Config in the mock class. See
the new patch.

+
+}  // namespace webrtc
+
+#endif  // WEBRTC_MODULES_AUDIO_CODING_AUDIO_NETWORK_ADAPTOR_CONTROLLER_MANAGER_H_