Tether MessageTransferOperation: Only wait for a response from a host for a certain amount of time …

chromeos/components/tether/message_transfer_operation.h

Index: chromeos/components/tether/message_transfer_operation.h
diff --git a/chromeos/components/tether/message_transfer_operation.h b/chromeos/components/tether/message_transfer_operation.h
index 3265214002750504c3e40f3c9e71205d82c4d08f..9d9e664e24e443794097b275694a080c7e011c74 100644
--- a/chromeos/components/tether/message_transfer_operation.h
+++ b/chromeos/components/tether/message_transfer_operation.h
@@ -9,6 +9,7 @@
 #include <vector>
 
 #include "base/macros.h"
+#include "base/timer/timer.h"
 #include "chromeos/components/tether/ble_connection_manager.h"
 
 namespace chromeos {
@@ -16,6 +17,7 @@ namespace chromeos {
 namespace tether {
 
 class MessageWrapper;
+class TimerFactory;
 
 // Abstract base class used for operations which send and/or receive messages
 // from remote devices.
@@ -70,10 +72,20 @@ class MessageTransferOperation : public BleConnectionManager::Observer {
   // Returns the type of message that this operation intends to send.
   virtual MessageType GetMessageTypeForConnection() = 0;
 
+  // Returns true if we should wait for a response from the host device.

[Kyle Horimoto, 2017/05/31 21:55:33]

Also describe what the consequences of this are (i.e., the timer will be started
and will automatically unregister a device if it fires).

[Ryan Hansberry, 2017/06/01 00:31:58]

Done.

+  virtual bool ShouldWaitForResponse();
+
+  // The number of seconds that we should wait for a response from the host. If
+  // ShouldWaitForResponse() returns false, this method is never used.
+  virtual uint32_t GetResponseTimeoutSeconds();
+
   std::vector<cryptauth::RemoteDevice>& remote_devices() {
     return remote_devices_;
   }
 
+  void SetTimerFactoryForTest(
+      std::unique_ptr<TimerFactory> timer_factory_for_test);
+
  private:
   friend class ConnectTetheringOperationTest;
   friend class DisconnectTetheringOperationTest;
@@ -82,12 +94,34 @@ class MessageTransferOperation : public BleConnectionManager::Observer {
 
   static uint32_t kMaxConnectionAttemptsPerDevice;
 
+  // The number of seconds the client should generally wait for a response from
+  // the host once an authenticated connection is established. Once this amount
+  // of time passes, the connection will be closed. Subclasses of
+  // MessageTransferOperation should override GetResponseTimeoutSeconds()
+  // if they desire a shorter or longer duration.
+  static uint32_t kResponseTimeoutSeconds;

[Kyle Horimoto, 2017/05/31 21:55:33]

Name this kDefaultResponseTimeoutSeconds and edit the description to say that
this is the default value.

[Ryan Hansberry, 2017/06/01 00:31:58]

Done.

+
+  void StartResponseTimerForDevice(
+      const cryptauth::RemoteDevice& remote_device);
+  void StopResponseTimerForDevice(const cryptauth::RemoteDevice& remote_device);
+  void OnResponseTimeout(const cryptauth::RemoteDevice& remote_device);
+
+  // Exposed for testing.
+  base::Timer* GetResponseTimerForDevice(
+      const cryptauth::RemoteDevice& remote_device) {
+    return remote_device_to_timer_map_[remote_device].get();
+  }
+
   std::vector<cryptauth::RemoteDevice> remote_devices_;
   BleConnectionManager* connection_manager_;
+  std::unique_ptr<TimerFactory> timer_factory_;
 
   bool initialized_;
   std::map<cryptauth::RemoteDevice, uint32_t>
       remote_device_to_num_attempts_map_;
+  std::map<cryptauth::RemoteDevice, std::unique_ptr<base::Timer>>
+      remote_device_to_timer_map_;
+  base::WeakPtrFactory<MessageTransferOperation> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(MessageTransferOperation);
 };