device/bluetooth: Update characteristic value D-Bus bindings.

The original BlueZ GATT API doc spec used DBus.Properties interface for
characteristic value access. Since we are modifying this API for Chrome OS,
this CL updates the Chrome D-Bus bindings and modifies the device/bluetooth
GATT code to use the new bindings for characteristic value reads, writes, and
updates.

BUG=378182
TEST=Tested against my custom bluetoothd build; device_unittests

Review URL: https://codereview.chromium.org/301093003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@275693 0039d316-1c4b-4281-b951-d872f2087c98

5 files changed, 252 insertions, 83 deletions

diff --git a/chromeos/dbus/bluetooth_gatt_characteristic_client.cc b/chromeos/dbus/bluetooth_gatt_characteristic_client.cc
index e2e7c74..a510b91 100644
--- a/chromeos/dbus/bluetooth_gatt_characteristic_client.cc
+++ b/chromeos/dbus/bluetooth_gatt_characteristic_client.cc
@@ -13,6 +13,13 @@
 
 namespace chromeos {
 
+// static
+const char BluetoothGattCharacteristicClient::kNoResponseError[] =
+    "org.chromium.Error.NoResponse";
+// static
+const char BluetoothGattCharacteristicClient::kUnknownCharacteristicError[] =
+    "org.chromium.Error.UnknownCharacteristic";
+
 BluetoothGattCharacteristicClient::Properties::Properties(
     dbus::ObjectProxy* object_proxy,
     const std::string& interface_name,
@@ -20,7 +27,6 @@ BluetoothGattCharacteristicClient::Properties::Properties(
     : dbus::PropertySet(object_proxy, interface_name, callback) {
   RegisterProperty(bluetooth_gatt_characteristic::kUUIDProperty, &uuid);
   RegisterProperty(bluetooth_gatt_characteristic::kServiceProperty, &service);
-  RegisterProperty(bluetooth_gatt_characteristic::kValueProperty, &value);
   RegisterProperty(bluetooth_gatt_characteristic::kFlagsProperty, &flags);
 }
 
@@ -74,6 +80,61 @@ class BluetoothGattCharacteristicClientImpl
                 kBluetoothGattCharacteristicInterface));
   }
 
+  // BluetoothGattCharacteristicClient override.
+  virtual void ReadValue(const dbus::ObjectPath& object_path,
+                         const ValueCallback& callback,
+                         const ErrorCallback& error_callback) OVERRIDE {
+    dbus::ObjectProxy* object_proxy =
+        object_manager_->GetObjectProxy(object_path);
+    if (!object_proxy) {
+      error_callback.Run(kUnknownCharacteristicError, "");
+      return;
+    }
+
+    dbus::MethodCall method_call(
+        bluetooth_gatt_characteristic::kBluetoothGattCharacteristicInterface,
+        bluetooth_gatt_characteristic::kReadValue);
+
+    object_proxy->CallMethodWithErrorCallback(
+        &method_call,
+        dbus::ObjectProxy::TIMEOUT_USE_DEFAULT,
+        base::Bind(&BluetoothGattCharacteristicClientImpl::OnValueSuccess,
+                   weak_ptr_factory_.GetWeakPtr(),
+                   callback),
+        base::Bind(&BluetoothGattCharacteristicClientImpl::OnError,
+                   weak_ptr_factory_.GetWeakPtr(),
+                   error_callback));
+  }
+
+  // BluetoothGattCharacteristicClient override.
+  virtual void WriteValue(const dbus::ObjectPath& object_path,
+                          const std::vector<uint8>& value,
+                          const base::Closure& callback,
+                          const ErrorCallback& error_callback) OVERRIDE {
+    dbus::ObjectProxy* object_proxy =
+        object_manager_->GetObjectProxy(object_path);
+    if (!object_proxy) {
+      error_callback.Run(kUnknownCharacteristicError, "");
+      return;
+    }
+
+    dbus::MethodCall method_call(
+        bluetooth_gatt_characteristic::kBluetoothGattCharacteristicInterface,
+        bluetooth_gatt_characteristic::kWriteValue);
+    dbus::MessageWriter writer(&method_call);
+    writer.AppendArrayOfBytes(value.data(), value.size());
+
+    object_proxy->CallMethodWithErrorCallback(
+        &method_call,
+        dbus::ObjectProxy::TIMEOUT_USE_DEFAULT,
+        base::Bind(&BluetoothGattCharacteristicClientImpl::OnSuccess,
+                   weak_ptr_factory_.GetWeakPtr(),
+                   callback),
+        base::Bind(&BluetoothGattCharacteristicClientImpl::OnError,
+                   weak_ptr_factory_.GetWeakPtr(),
+                   error_callback));
+  }
+
   // dbus::ObjectManager::Interface override.
   virtual dbus::PropertySet* CreateProperties(
       dbus::ObjectProxy *object_proxy,
@@ -94,6 +155,21 @@ class BluetoothGattCharacteristicClientImpl
     VLOG(2) << "Remote GATT characteristic added: " << object_path.value();
     FOR_EACH_OBSERVER(BluetoothGattCharacteristicClient::Observer, observers_,
                       GattCharacteristicAdded(object_path));
+
+    // Connect the "ValueUpdated" signal.
+    dbus::ObjectProxy* object_proxy =
+        object_manager_->GetObjectProxy(object_path);
+    DCHECK(object_proxy);
+
+    object_proxy->ConnectToSignal(
+        bluetooth_gatt_characteristic::kBluetoothGattCharacteristicInterface,
+        bluetooth_gatt_characteristic::kValueUpdatedSignal,
+        base::Bind(&BluetoothGattCharacteristicClientImpl::ValueUpdatedReceived,
+                   weak_ptr_factory_.GetWeakPtr(),
+                   object_path),
+        base::Bind(
+            &BluetoothGattCharacteristicClientImpl::ValueUpdatedConnected,
+            weak_ptr_factory_.GetWeakPtr()));
   }
 
   // dbus::ObjectManager::Interface override.
@@ -129,6 +205,78 @@ class BluetoothGattCharacteristicClientImpl
                                                         property_name));
   }
 
+  // Called by dbus:: when a "ValueUpdated" signal is received.
+  void ValueUpdatedReceived(const dbus::ObjectPath& object_path,
+                            dbus::Signal* signal) {
+    DCHECK(signal);
+    const uint8* bytes = NULL;
+    size_t length = 0;
+    dbus::MessageReader reader(signal);
+    if (!reader.PopArrayOfBytes(&bytes, &length)) {
+      LOG(WARNING) << "ValueUpdated signal has incorrect parameters: "
+                   << signal->ToString();
+      return;
+    }
+
+    std::vector<uint8> value;
+    if (bytes)
+      value.assign(bytes, bytes + length);
+
+    FOR_EACH_OBSERVER(BluetoothGattCharacteristicClient::Observer,
+                      observers_,
+                      GattCharacteristicValueUpdated(object_path, value));
+  }
+
+  // Called by dbus:: when the "ValueUpdated" signal is initially connected.
+  void ValueUpdatedConnected(const std::string& interface_name,
+                             const std::string& signal_name,
+                             bool success) {
+    LOG_IF(WARNING, !success) << "Failed to connect to the ValueUpdated signal";
+  }
+
+  // Called when a response for successful method call is received.
+  void OnSuccess(const base::Closure& callback, dbus::Response* response) {
+    DCHECK(response);
+    callback.Run();
+  }
+
+  // Called when a characteristic value response for a successful method call
+  // is received.
+  void OnValueSuccess(const ValueCallback& callback, dbus::Response* response) {
+    DCHECK(response);
+    dbus::MessageReader reader(response);
+
+    const uint8* bytes = NULL;
+    size_t length = 0;
+
+    if (!reader.PopArrayOfBytes(&bytes, &length))
+      VLOG(2) << "Error reading array of bytes in ValueCallback";
+
+    std::vector<uint8> value;
+
+    if (bytes)
+      value.assign(bytes, bytes + length);
+
+    callback.Run(value);
+  }
+
+  // Called when a response for a failed method call is received.
+  void OnError(const ErrorCallback& error_callback,
+               dbus::ErrorResponse* response) {
+    // Error response has optional error message argument.
+    std::string error_name;
+    std::string error_message;
+    if (response) {
+      dbus::MessageReader reader(response);
+      error_name = response->GetErrorName();
+      reader.PopString(&error_message);
+    } else {
+      error_name = kNoResponseError;
+      error_message = "";
+    }
+    error_callback.Run(error_name, error_message);
+  }
+
   dbus::ObjectManager* object_manager_;
 
   // List of observers interested in event notifications from us.
diff --git a/chromeos/dbus/bluetooth_gatt_characteristic_client.h b/chromeos/dbus/bluetooth_gatt_characteristic_client.h
index 2935e4a..e5d48ad 100644
--- a/chromeos/dbus/bluetooth_gatt_characteristic_client.h
+++ b/chromeos/dbus/bluetooth_gatt_characteristic_client.h
@@ -8,6 +8,7 @@
 #include <string>
 
 #include "base/basictypes.h"
+#include "base/callback.h"
 #include "chromeos/chromeos_export.h"
 #include "chromeos/dbus/dbus_client.h"
 #include "dbus/object_path.h"
@@ -28,10 +29,6 @@ class CHROMEOS_EXPORT BluetoothGattCharacteristicClient : public DBusClient {
     // [read-only]
     dbus::Property<dbus::ObjectPath> service;
 
-    // Characteristic value read from the remote Bluetooth device. Setting the
-    // value sends a write request to the remote device. [read-write]
-    dbus::Property<std::vector<uint8> > value;
-
     // List of flags representing the GATT "Characteristic Properties bit field"
     // and properties read from the GATT "Characteristic Extended Properties"
     // descriptor bit field. [read-only, optional]
@@ -62,8 +59,20 @@ class CHROMEOS_EXPORT BluetoothGattCharacteristicClient : public DBusClient {
     virtual void GattCharacteristicPropertyChanged(
         const dbus::ObjectPath& object_path,
         const std::string& property_name) {}
+
+    // Called when a "ValueUpdated" signal is received from the remote GATT
+    // characteristic with object path |object_path| with characteristic value
+    // |value|.
+    virtual void GattCharacteristicValueUpdated(
+        const dbus::ObjectPath& object_path,
+        const std::vector<uint8>& value) {}
   };
 
+  // Callbacks used to report the result of asynchronous methods.
+  typedef base::Callback<void(const std::string& error_name,
+                              const std::string& error_message)> ErrorCallback;
+  typedef base::Callback<void(const std::vector<uint8>& value)> ValueCallback;
+
   virtual ~BluetoothGattCharacteristicClient();
 
   // Adds and removes observers for events on all remote GATT characteristics.
@@ -79,9 +88,28 @@ class CHROMEOS_EXPORT BluetoothGattCharacteristicClient : public DBusClient {
   // |object_path|. Values should be copied if needed.
   virtual Properties* GetProperties(const dbus::ObjectPath& object_path) = 0;
 
+  // Issues a request to read the value of GATT characteristic with object path
+  // |object_path| and returns the value in |callback| on success. On error,
+  // invokes |error_callback|.
+  virtual void ReadValue(const dbus::ObjectPath& object_path,
+                         const ValueCallback& callback,
+                         const ErrorCallback& error_callback) = 0;
+
+  // Issues a request to write the value of GATT characteristic with object path
+  // |object_path| with value |value|. Invokes |callback| on success and
+  // |error_callback| on failure.
+  virtual void WriteValue(const dbus::ObjectPath& object_path,
+                          const std::vector<uint8>& value,
+                          const base::Closure& callback,
+                          const ErrorCallback& error_callback) = 0;
+
   // Creates the instance.
   static BluetoothGattCharacteristicClient* Create();
 
+  // Constants used to indicate exceptional error conditions.
+  static const char kNoResponseError[];
+  static const char kUnknownCharacteristicError[];
+
  protected:
   BluetoothGattCharacteristicClient();
 
diff --git a/chromeos/dbus/bluetooth_gatt_service_client.cc b/chromeos/dbus/bluetooth_gatt_service_client.cc
index 1888e51..83ce29a 100644
--- a/chromeos/dbus/bluetooth_gatt_service_client.cc
+++ b/chromeos/dbus/bluetooth_gatt_service_client.cc
@@ -13,15 +13,6 @@
 
 namespace chromeos {
 
-namespace {
-
-// TODO(armansito): Add these to service_constants.h when they are defined
-// in the BlueZ doc.
-const char kDeviceProperty[] = "Device";
-const char kPrimaryProperty[] = "Primary";
-
-}  // namespace
-
 BluetoothGattServiceClient::Properties::Properties(
     dbus::ObjectProxy* object_proxy,
     const std::string& interface_name,
@@ -29,8 +20,8 @@ BluetoothGattServiceClient::Properties::Properties(
     : dbus::PropertySet(object_proxy, interface_name, callback) {
   RegisterProperty(bluetooth_gatt_service::kUUIDProperty, &uuid);
   RegisterProperty(bluetooth_gatt_service::kIncludesProperty, &includes);
-  RegisterProperty(kDeviceProperty, &device);
-  RegisterProperty(kPrimaryProperty, &primary);
+  RegisterProperty(bluetooth_gatt_service::kDeviceProperty, &device);
+  RegisterProperty(bluetooth_gatt_service::kPrimaryProperty, &primary);
 }
 
 BluetoothGattServiceClient::Properties::~Properties() {
diff --git a/chromeos/dbus/fake_bluetooth_gatt_characteristic_client.cc b/chromeos/dbus/fake_bluetooth_gatt_characteristic_client.cc
index c822f95..0010ace 100644
--- a/chromeos/dbus/fake_bluetooth_gatt_characteristic_client.cc
+++ b/chromeos/dbus/fake_bluetooth_gatt_characteristic_client.cc
@@ -51,9 +51,6 @@ void FakeBluetoothGattCharacteristicClient::Properties::Get(
     dbus::PropertyBase* property,
     dbus::PropertySet::GetCallback callback) {
   VLOG(1) << "Get " << property->name();
-
-  // TODO(armansito): Return success or failure here based on characteristic
-  // read permission.
   callback.Run(true);
 }
 
@@ -65,34 +62,7 @@ void FakeBluetoothGattCharacteristicClient::Properties::Set(
     dbus::PropertyBase* property,
     dbus::PropertySet::SetCallback callback) {
   VLOG(1) << "Set " << property->name();
-  if (property->name() != value.name()) {
-    callback.Run(false);
-    return;
-  }
-
-  // Allow writing to only certain characteristics that are defined with the
-  // write permission.
-  bool write = false;
-  for (std::vector<std::string>::const_iterator iter = flags.value().begin();
-       iter != flags.value().end();
-       ++iter) {
-    if (*iter == bluetooth_gatt_characteristic::kFlagWrite ||
-        *iter == bluetooth_gatt_characteristic::kFlagWriteWithoutResponse ||
-        *iter ==
-            bluetooth_gatt_characteristic::kFlagAuthenticatedSignedWrites ||
-        *iter == bluetooth_gatt_characteristic::kFlagReliableWrite) {
-      write = true;
-      break;
-    }
-  }
-
-  if (!write) {
-    callback.Run(false);
-    return;
-  }
-
-  callback.Run(true);
-  property->ReplaceValueWithSetValue();
+  callback.Run(false);
 }
 
 FakeBluetoothGattCharacteristicClient::FakeBluetoothGattCharacteristicClient()
@@ -145,6 +115,61 @@ FakeBluetoothGattCharacteristicClient::GetProperties(
   return NULL;
 }
 
+void FakeBluetoothGattCharacteristicClient::ReadValue(
+    const dbus::ObjectPath& object_path,
+    const ValueCallback& callback,
+    const ErrorCallback& error_callback) {
+  if (!IsHeartRateVisible()) {
+    error_callback.Run(kUnknownCharacteristicError, "");
+    return;
+  }
+
+  if (object_path.value() == heart_rate_measurement_path_ ||
+      object_path.value() == heart_rate_control_point_path_) {
+    error_callback.Run("org.bluez.Error.ReadNotPermitted",
+                       "Reads of this value are not allowed");
+    return;
+  }
+
+  if (object_path.value() != body_sensor_location_path_) {
+    error_callback.Run(kUnknownCharacteristicError, "");
+    return;
+  }
+
+  std::vector<uint8> value;
+  value.push_back(0x06);  // Location is "foot".
+  callback.Run(value);
+}
+
+void FakeBluetoothGattCharacteristicClient::WriteValue(
+    const dbus::ObjectPath& object_path,
+    const std::vector<uint8>& value,
+    const base::Closure& callback,
+    const ErrorCallback& error_callback) {
+  if (!IsHeartRateVisible()) {
+    error_callback.Run(kUnknownCharacteristicError, "");
+    return;
+  }
+
+  if (object_path.value() != heart_rate_control_point_path_) {
+    error_callback.Run("org.bluez.Error.WriteNotPermitted",
+                       "Writes of this value are not allowed");
+    return;
+  }
+
+  DCHECK(heart_rate_control_point_properties_.get());
+  if (value.size() != 1 || value[0] > 1) {
+    error_callback.Run("org.bluez.Error.Failed",
+                       "Invalid value given for write");
+    return;
+  }
+
+  if (value[0] == 1)
+    calories_burned_ = 0;
+
+  callback.Run();
+}
+
 void FakeBluetoothGattCharacteristicClient::ExposeHeartRateCharacteristics(
     const dbus::ObjectPath& service_path) {
   if (IsHeartRateVisible()) {
@@ -169,9 +194,6 @@ void FakeBluetoothGattCharacteristicClient::ExposeHeartRateCharacteristics(
   flags.push_back(bluetooth_gatt_characteristic::kFlagNotify);
   heart_rate_measurement_properties_->flags.ReplaceValue(flags);
 
-  std::vector<uint8> measurement_value = GetHeartRateMeasurementValue();
-  heart_rate_measurement_properties_->value.ReplaceValue(measurement_value);
-
   // ==== Body Sensor Location Characteristic ====
   body_sensor_location_path_ =
       service_path.value() + "/" + kBodySensorLocationPathComponent;
@@ -185,12 +207,6 @@ void FakeBluetoothGattCharacteristicClient::ExposeHeartRateCharacteristics(
   flags.push_back(bluetooth_gatt_characteristic::kFlagRead);
   body_sensor_location_properties_->flags.ReplaceValue(flags);
 
-  // The sensor is in the "Other" location.
-  std::vector<uint8> body_sensor_location_value;
-  body_sensor_location_value.push_back(0);
-  body_sensor_location_properties_->value.ReplaceValue(
-      body_sensor_location_value);
-
   // ==== Heart Rate Control Point Characteristic ====
   heart_rate_control_point_path_ =
       service_path.value() + "/" + kHeartRateControlPointPathComponent;
@@ -205,13 +221,6 @@ void FakeBluetoothGattCharacteristicClient::ExposeHeartRateCharacteristics(
   flags.push_back(bluetooth_gatt_characteristic::kFlagWrite);
   heart_rate_control_point_properties_->flags.ReplaceValue(flags);
 
-  // Set the initial value to 0. Whenever this gets set to 1, we will reset the
-  // total calories burned and change the value back to 0.
-  std::vector<uint8> heart_rate_control_point_value;
-  heart_rate_control_point_value.push_back(0);
-  heart_rate_control_point_properties_->value.ReplaceValue(
-      heart_rate_control_point_value);
-
   heart_rate_visible_ = true;
 
   NotifyCharacteristicAdded(dbus::ObjectPath(heart_rate_measurement_path_));
@@ -286,25 +295,6 @@ void FakeBluetoothGattCharacteristicClient::OnPropertyChanged(
   FOR_EACH_OBSERVER(BluetoothGattCharacteristicClient::Observer, observers_,
                     GattCharacteristicPropertyChanged(
                         object_path, property_name));
-
-  // If the heart rate control point was set, reset the calories burned.
-  if (object_path.value() != heart_rate_control_point_path_)
-    return;
-  DCHECK(heart_rate_control_point_properties_.get());
-  dbus::Property<std::vector<uint8> >* value_prop =
-      &heart_rate_control_point_properties_->value;
-  if (property_name != value_prop->name())
-    return;
-
-  std::vector<uint8> value = value_prop->value();
-  DCHECK(value.size() == 1);
-  if (value[0] == 0)
-    return;
-
-  DCHECK(value[0] == 1);
-  calories_burned_ = 0;
-  value[0] = 0;
-  value_prop->ReplaceValue(value);
 }
 
 void FakeBluetoothGattCharacteristicClient::NotifyCharacteristicAdded(
@@ -327,7 +317,12 @@ void FakeBluetoothGattCharacteristicClient::
     return;
   VLOG(2) << "Updating heart rate value.";
   std::vector<uint8> measurement = GetHeartRateMeasurementValue();
-  heart_rate_measurement_properties_->value.ReplaceValue(measurement);
+
+  FOR_EACH_OBSERVER(
+      BluetoothGattCharacteristicClient::Observer,
+      observers_,
+      GattCharacteristicValueUpdated(
+          dbus::ObjectPath(heart_rate_measurement_path_), measurement));
 
   base::MessageLoop::current()->PostDelayedTask(
       FROM_HERE,
diff --git a/chromeos/dbus/fake_bluetooth_gatt_characteristic_client.h b/chromeos/dbus/fake_bluetooth_gatt_characteristic_client.h
index 1ae77cb..2f23586 100644
--- a/chromeos/dbus/fake_bluetooth_gatt_characteristic_client.h
+++ b/chromeos/dbus/fake_bluetooth_gatt_characteristic_client.h
@@ -49,6 +49,13 @@ class CHROMEOS_EXPORT FakeBluetoothGattCharacteristicClient
   virtual std::vector<dbus::ObjectPath> GetCharacteristics() OVERRIDE;
   virtual Properties* GetProperties(const dbus::ObjectPath& object_path)
       OVERRIDE;
+  virtual void ReadValue(const dbus::ObjectPath& object_path,
+                         const ValueCallback& callback,
+                         const ErrorCallback& error_callback) OVERRIDE;
+  virtual void WriteValue(const dbus::ObjectPath& object_path,
+                          const std::vector<uint8>& value,
+                          const base::Closure& callback,
+                          const ErrorCallback& error_callback) OVERRIDE;
 
   // Makes the group of characteristics belonging to a particular GATT based
   // profile available under the GATT service with object path |service_path|.