bluetooth: Create base class BluetoothDevice::CreateGattConnection impl.

device/bluetooth/bluetooth_device.h

 // Copyright (c) 2012 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 DEVICE_BLUETOOTH_BLUETOOTH_DEVICE_H_
 #define DEVICE_BLUETOOTH_BLUETOOTH_DEVICE_H_
 
 #include <map>
+#include <set>
 #include <string>
 #include <vector>
 
 #include "base/callback.h"
 #include "base/memory/ref_counted.h"
+#include "base/numerics/safe_math.h"
 #include "base/strings/string16.h"
 #include "device/bluetooth/bluetooth_export.h"
 #include "device/bluetooth/bluetooth_uuid.h"
 #include "net/log/net_log.h"
 
 namespace base {
 class BinaryValue;
 }
 
 namespace device {
@@ skipping 208 matching lines @@
   virtual bool IsPaired() const = 0;
 
   // Indicates whether the device is currently connected to the adapter.
   // Note that if IsConnected() is true, does not imply that the device is
   // connected to any application or service. If the device is not paired, it
   // could be still connected to the adapter for other reason, for example, to
   // request the adapter's SDP records. The same holds for paired devices, since
   // they could be connected to the adapter but not to an application.
   virtual bool IsConnected() const = 0;
 
+  // Indicates whether an active GATT connection exists to the device.
+  virtual bool IsGattConnected() const = 0;
+
   // Indicates whether the paired device accepts connections initiated from the
   // adapter. This value is undefined for unpaired devices.
   virtual bool IsConnectable() const = 0;
 
   // Indicates whether there is a call to Connect() ongoing. For this attribute,
   // we consider a call is ongoing if none of the callbacks passed to Connect()
   // were called after the corresponding call to Connect().
   virtual bool IsConnecting() const = 0;
 
   // Indicates whether the device can be trusted, based on device properties,
@@ skipping 147 matching lines @@
   // BluetoothGattConnection will be handed to the caller via |callback|. On
   // error, |error_callback| will be called. The connection will be kept alive,
   // as long as there is at least one active GATT connection. In the case that
   // the underlying connection gets terminated, either due to a call to
   // BluetoothDevice::Disconnect or other unexpected circumstances, the
   // returned BluetoothGattConnection will be automatically marked as inactive.
   // To monitor the state of the connection, observe the
   // BluetoothAdapter::Observer::DeviceChanged method.
   typedef base::Callback<void(scoped_ptr<BluetoothGattConnection>)>
       GattConnectionCallback;
-  virtual void CreateGattConnection(
-      const GattConnectionCallback& callback,
-      const ConnectErrorCallback& error_callback) = 0;
+  virtual void CreateGattConnection(const GattConnectionCallback& callback,
+                                    const ConnectErrorCallback& error_callback);
 
   // Returns the list of discovered GATT services.
   virtual std::vector<BluetoothGattService*> GetGattServices() const;
 
   // Returns the GATT service with device-specific identifier |identifier|.
   // Returns NULL, if no such service exists.
   virtual BluetoothGattService* GetGattService(
       const std::string& identifier) const;
 
   // Returns service data of a service given its UUID.
   virtual base::BinaryValue* GetServiceData(BluetoothUUID serviceUUID) const;
 
   // Returns the list UUIDs of services that have service data.
   virtual UUIDList GetServiceDataUUIDs() const;
 
   // Returns the |address| in the canonical format: XX:XX:XX:XX:XX:XX, where
   // each 'X' is a hex digit.  If the input |address| is invalid, returns an
   // empty string.
   static std::string CanonicalizeAddress(const std::string& address);
 
  protected:
+  // BluetoothGattConnection is a friend to call Add/RemoveGattConnection.
+  friend BluetoothGattConnection;
+
   BluetoothDevice(BluetoothAdapter* adapter);
 
   // Returns the internal name of the Bluetooth device, used by GetName().
   virtual std::string GetDeviceName() const = 0;
 
+  // Implements platform specific operations to initiate a GATT connection.
+  // Subclasses must also call DidConnectGatt, DidFailToConnectGatt, or
+  // DidDisconnectGatt immediately or asynchronously as the connection state
+  // changes.
+  virtual void CreateGattConnectionImpl() = 0;
+
+  // Disconnects GATT connection on platforms that maintain a specific GATT
+  // connection.
+  virtual void DisconnectGatt() = 0;
+
+  // Calls any pending callbacks for CreateGattConnection based on result of
+  // subclasses actions initiated in CreateGattConnectionImpl or related
+  // disconnection events. These may be called at any time, even multiple times,

[Jeffrey Yasskin, 2015/09/16 00:45:39]

The implementation says DidDisconnectGatt() shouldn't be called between
CreateGattConnectionImpl() and the next call to either DidConnectGatt() and
DidFailToConnectGatt().

[scheib, 2015/09/16 21:19:08]

Done.

+  // to ensure a change in platform state is correctly tracked.
+  void DidConnectGatt();
+  void DidFailToConnectGatt(ConnectErrorCode);
+  void DidDisconnectGatt();
+
+  // Maintains GattConnection reference count by tracking friend class
+  // BluetoothGattConnection instances.

[Jeffrey Yasskin, 2015/09/16 00:45:39]

Is it too obvious to say that the BluetoothGattConnection is responsible to call
RemoveGattConnection(this) before it's destroyed?

[scheib, 2015/09/16 21:19:08]

Done.

+  void AddGattConnection(BluetoothGattConnection*);
+  void RemoveGattConnection(BluetoothGattConnection*);
+
   // Clears the list of service data.
   void ClearServiceData();
 
   // Set the data of a given service designated by its UUID.
   void SetServiceData(BluetoothUUID serviceUUID, const char* buffer,
                       size_t size);
 
   // Raw pointer to adapter owning this device object. Subclasses use platform
   // specific pointers via adapter_.
   BluetoothAdapter* adapter_;
 
+  // Callbacks for pending success and error result of CreateGattConnection.
+  std::vector<GattConnectionCallback> create_gatt_connection_success_callbacks_;
+  std::vector<ConnectErrorCallback> create_gatt_connection_error_callbacks_;
+
+  // BluetoothGattConnection objects keeping the GATT connection alive.
+  std::set<BluetoothGattConnection*> gatt_connections_;
+
   // Mapping from the platform-specific GATT service identifiers to
   // BluetoothGattService objects.
   typedef std::map<std::string, BluetoothGattService*> GattServiceMap;
   GattServiceMap gatt_services_;
 
   // Mapping from service UUID represented as a std::string of a bluetooth
   // service to
   // the specific data. The data is stored as BinaryValue.
   scoped_ptr<base::DictionaryValue> services_data_;
 
  private:
   // Returns a localized string containing the device's bluetooth address and
   // a device type for display when |name_| is empty.
   base::string16 GetAddressWithLocalizedDeviceTypeName() const;
 };
 
 }  // namespace device
 
 #endif  // DEVICE_BLUETOOTH_BLUETOOTH_DEVICE_H_