arc: bluetooth: Implement Gatt Server add/delete/start/stop service

components/arc/bluetooth/arc_bluetooth_bridge.cc

Index: components/arc/bluetooth/arc_bluetooth_bridge.cc
diff --git a/components/arc/bluetooth/arc_bluetooth_bridge.cc b/components/arc/bluetooth/arc_bluetooth_bridge.cc
index 7eaf57aa1dd55e8300096956b7fc9de23c9553f3..d9a373b1388e17da362347d78e7328d4325ab956 100644
--- a/components/arc/bluetooth/arc_bluetooth_bridge.cc
+++ b/components/arc/bluetooth/arc_bluetooth_bridge.cc
@@ -60,6 +60,83 @@ constexpr uint32_t kGattWritePermission =
     BluetoothGattCharacteristic::Permission::PERMISSION_WRITE_ENCRYPTED |
     BluetoothGattCharacteristic::Permission::
         PERMISSION_WRITE_ENCRYPTED_AUTHENTICATED;
+constexpr int32_t kInvalidGattAttributeHandle = -1;
+
+using GattStatusCallback =
+    base::Callback<void(arc::mojom::BluetoothGattStatus)>;
+using GattReadCallback =
+    base::Callback<void(arc::mojom::BluetoothGattValuePtr)>;
+
+// Example of identifier: /org/bluez/hci0/dev_E0_CF_65_8C_86_1A/service001a
+// We want to convert last digit of the identifier to int in base 16
+int ConvertGattIdentifierToId(const std::string identifier) {
+  return std::stoi(identifier.substr(identifier.size() - 4), nullptr, 16);
+}
+
+// Create GattDBElement and fill in common data for
+// Gatt Service/Characteristic/Descriptor.
+template <class RemoteGattAttribute>
+arc::mojom::BluetoothGattDBElementPtr CreateGattDBElement(
+    const arc::mojom::BluetoothGattDBAttributeType type,
+    const RemoteGattAttribute* gatt_attr) {
+  arc::mojom::BluetoothGattDBElementPtr element =
+      arc::mojom::BluetoothGattDBElement::New();
+  element->type = type;
+  element->uuid = arc::mojom::BluetoothUUID::From(gatt_attr->GetUUID());
+  element->id = element->attribute_handle = element->start_handle =
+      element->end_handle =
+          ConvertGattIdentifierToId(gatt_attr->GetIdentifier());
+  element->properties = 0;
+  return element;
+}
+
+// Find Gatt Service/Characteristic/Descriptor from std::vector using UUID.
+template <class RemoteGattAttribute>
+RemoteGattAttribute* FindGattAttributeFromUuid(
+    const std::vector<RemoteGattAttribute*> gatt_attrs,

[Luis Héctor Chávez, 2016/07/20 23:11:04]

should this be a const-reference?

[puthik_chromium, 2016/07/21 00:05:04]

Done.

+    const device::BluetoothUUID uuid) {
+  auto it = std::find_if(
+      gatt_attrs.begin(), gatt_attrs.end(),
+      [uuid](RemoteGattAttribute* attr) { return attr->GetUUID() == uuid; });
+  if (it == gatt_attrs.end())
+    return nullptr;
+  return *it;
+}
+
+// Common success callback for GATT operations that only need to report
+// GattStatus back to Android.
+void OnGattOperationDone(const GattStatusCallback& callback) {
+  callback.Run(arc::mojom::BluetoothGattStatus::GATT_SUCCESS);
+}
+
+// Common error callback for GATT operations that only need to report
+// GattStatus back to Android.
+void OnGattOperationError(const GattStatusCallback& callback,
+                          BluetoothGattService::GattErrorCode error_code) {
+  callback.Run(mojo::ConvertTo<arc::mojom::BluetoothGattStatus>(error_code));
+}
+
+// Common success callback for ReadGattCharacteristic and ReadGattDescriptor
+void OnGattReadDone(const GattReadCallback& callback,
+                    const std::vector<uint8_t>& result) {
+  arc::mojom::BluetoothGattValuePtr gattValue =
+      arc::mojom::BluetoothGattValue::New();
+  gattValue->status = arc::mojom::BluetoothGattStatus::GATT_SUCCESS;
+  gattValue->value = mojo::Array<uint8_t>::From(result);
+  callback.Run(std::move(gattValue));
+}
+
+// Common error callback for ReadGattCharacteristic and ReadGattDescriptor
+void OnGattReadError(const GattReadCallback& callback,
+                     BluetoothGattService::GattErrorCode error_code) {
+  arc::mojom::BluetoothGattValuePtr gattValue =
+      arc::mojom::BluetoothGattValue::New();
+  gattValue->status =
+      mojo::ConvertTo<arc::mojom::BluetoothGattStatus>(error_code);
+  gattValue->value = nullptr;
+  callback.Run(std::move(gattValue));
+}
+
 }  // namespace
 
 namespace arc {
@@ -78,6 +155,8 @@ ArcBluetoothBridge::ArcBluetoothBridge(ArcBridgeService* bridge_service)
 }
 
 ArcBluetoothBridge::~ArcBluetoothBridge() {
+  DCHECK(CalledOnValidThread());
+
   arc_bridge_service()->bluetooth()->RemoveObserver(this);
 
   if (bluetooth_adapter_)
@@ -86,6 +165,8 @@ ArcBluetoothBridge::~ArcBluetoothBridge() {
 
 void ArcBluetoothBridge::OnAdapterInitialized(
     scoped_refptr<BluetoothAdapter> adapter) {
+  DCHECK(CalledOnValidThread());
+
   // We can downcast here because we are always running on Chrome OS, and
   // so our adapter uses BlueZ.
   bluetooth_adapter_ =
@@ -106,6 +187,8 @@ void ArcBluetoothBridge::OnInstanceReady() {
 
 void ArcBluetoothBridge::AdapterPresentChanged(BluetoothAdapter* adapter,
                                                bool present) {
+  DCHECK(CalledOnValidThread());
+
   // If the adapter goes away, remove ourselves as an observer.
   if (!present && adapter == bluetooth_adapter_) {
     adapter->RemoveObserver(this);
@@ -743,30 +826,6 @@ void ArcBluetoothBridge::StopLEListen(const StopLEListenCallback& callback) {
                                        weak_factory_.GetWeakPtr(), callback));
 }
 
-// Example of identifier: /org/bluez/hci0/dev_E0_CF_65_8C_86_1A/service001a
-// We want to convert last digit of the identifier to int in base 16
-int ArcBluetoothBridge::ConvertGattIdentifierToId(
-    const std::string identifier) const {
-  return std::stoi(identifier.substr(identifier.size() - 4), nullptr, 16);
-}
-
-// Create GattDBElement and fill in common data for
-// Gatt Service/Characteristic/Descriptor.
-template <class T>
-mojom::BluetoothGattDBElementPtr ArcBluetoothBridge::CreateGattDBElement(
-    const mojom::BluetoothGattDBAttributeType type,
-    const T* gattObject) const {
-  mojom::BluetoothGattDBElementPtr element =
-      mojom::BluetoothGattDBElement::New();
-  element->type = type;
-  element->uuid = mojom::BluetoothUUID::From(gattObject->GetUUID());
-  element->id = element->attribute_handle = element->start_handle =
-      element->end_handle =
-          ConvertGattIdentifierToId(gattObject->GetIdentifier());
-  element->properties = 0;
-  return element;
-}
-
 void ArcBluetoothBridge::GetGattDB(mojom::BluetoothAddressPtr remote_addr) {
   if (!HasBluetoothInstance())
     return;
@@ -813,18 +872,6 @@ void ArcBluetoothBridge::GetGattDB(mojom::BluetoothAddressPtr remote_addr) {
       std::move(remote_addr), std::move(db));
 }
 
-// Find Gatt Service/Characteristic/Descriptor from std::vector from UUID.
-template <class T>
-T* ArcBluetoothBridge::FindGattObjectFromUuid(
-    const std::vector<T*> gatt_objs,
-    const device::BluetoothUUID uuid) const {
-  auto it = std::find_if(gatt_objs.begin(), gatt_objs.end(),
-                         [&](T* obj) { return obj->GetUUID() == uuid; });
-  if (it == gatt_objs.end())
-    return nullptr;
-  return *it;
-}
-
 BluetoothRemoteGattCharacteristic* ArcBluetoothBridge::FindGattCharacteristic(
     mojom::BluetoothAddressPtr remote_addr,
     mojom::BluetoothGattServiceIDPtr service_id,
@@ -839,12 +886,12 @@ BluetoothRemoteGattCharacteristic* ArcBluetoothBridge::FindGattCharacteristic(
     return nullptr;
 
   BluetoothRemoteGattService* service =
-      FindGattObjectFromUuid<BluetoothRemoteGattService>(
+      FindGattAttributeFromUuid<BluetoothRemoteGattService>(

[Luis Héctor Chávez, 2016/07/20 23:11:04]

nit: C++ might be able to autodeduce the template type based on the parameters,
which should net you slightly more concise code.

[puthik_chromium, 2016/07/21 00:05:03]

Done.

           device->GetGattServices(), service_id->id->uuid.To<BluetoothUUID>());
   if (!service)
     return nullptr;
 
-  return FindGattObjectFromUuid<BluetoothRemoteGattCharacteristic>(
+  return FindGattAttributeFromUuid<BluetoothRemoteGattCharacteristic>(
       service->GetCharacteristics(), char_id->uuid.To<BluetoothUUID>());
 }
 
@@ -858,42 +905,10 @@ BluetoothRemoteGattDescriptor* ArcBluetoothBridge::FindGattDescriptor(
   if (!characteristic)
     return nullptr;
 
-  return FindGattObjectFromUuid<BluetoothRemoteGattDescriptor>(
+  return FindGattAttributeFromUuid<BluetoothRemoteGattDescriptor>(
       characteristic->GetDescriptors(), desc_id->uuid.To<BluetoothUUID>());
 }
 
-// Same callback for both ReadGattCharacteristic and ReadGattDescriptor
-void ArcBluetoothBridge::OnGattReadDone(
-    const GattReadCallback& callback,
-    const std::vector<uint8_t>& result) const {
-  mojom::BluetoothGattValuePtr gattValue = mojom::BluetoothGattValue::New();
-  gattValue->status = mojom::BluetoothGattStatus::GATT_SUCCESS;
-  gattValue->value = mojo::Array<uint8_t>::From(result);
-  callback.Run(std::move(gattValue));
-}
-
-void ArcBluetoothBridge::OnGattReadError(
-    const GattReadCallback& callback,
-    BluetoothGattService::GattErrorCode error_code) const {
-  mojom::BluetoothGattValuePtr gattValue = mojom::BluetoothGattValue::New();
-  gattValue->status = mojo::ConvertTo<mojom::BluetoothGattStatus>(error_code);
-  gattValue->value = nullptr;
-
-  callback.Run(std::move(gattValue));
-}
-
-// Same callback for both WriteGattCharacteristic and WriteGattDescriptor
-void ArcBluetoothBridge::OnGattWriteDone(
-    const GattWriteCallback& callback) const {
-  callback.Run(mojom::BluetoothGattStatus::GATT_SUCCESS);
-}
-
-void ArcBluetoothBridge::OnGattWriteError(
-    const GattWriteCallback& callback,
-    BluetoothGattService::GattErrorCode error_code) const {
-  callback.Run(mojo::ConvertTo<mojom::BluetoothGattStatus>(error_code));
-}
-
 void ArcBluetoothBridge::ReadGattCharacteristic(
     mojom::BluetoothAddressPtr remote_addr,
     mojom::BluetoothGattServiceIDPtr service_id,
@@ -905,10 +920,8 @@ void ArcBluetoothBridge::ReadGattCharacteristic(
   DCHECK(characteristic->GetPermissions() & kGattReadPermission);
 
   characteristic->ReadRemoteCharacteristic(
-      base::Bind(&ArcBluetoothBridge::OnGattReadDone,
-                 weak_factory_.GetWeakPtr(), callback),
-      base::Bind(&ArcBluetoothBridge::OnGattReadError,
-                 weak_factory_.GetWeakPtr(), callback));
+      base::Bind(&OnGattReadDone, callback),
+      base::Bind(&OnGattReadError, callback));
 }
 
 void ArcBluetoothBridge::WriteGattCharacteristic(
@@ -924,10 +937,8 @@ void ArcBluetoothBridge::WriteGattCharacteristic(
 
   characteristic->WriteRemoteCharacteristic(
       value->value.To<std::vector<uint8_t>>(),
-      base::Bind(&ArcBluetoothBridge::OnGattWriteDone,
-                 weak_factory_.GetWeakPtr(), callback),
-      base::Bind(&ArcBluetoothBridge::OnGattWriteError,
-                 weak_factory_.GetWeakPtr(), callback));
+      base::Bind(&OnGattOperationDone, callback),
+      base::Bind(&OnGattOperationError, callback));
 }
 
 void ArcBluetoothBridge::ReadGattDescriptor(
@@ -942,11 +953,8 @@ void ArcBluetoothBridge::ReadGattDescriptor(
   DCHECK(descriptor);
   DCHECK(descriptor->GetPermissions() & kGattReadPermission);
 
-  descriptor->ReadRemoteDescriptor(
-      base::Bind(&ArcBluetoothBridge::OnGattReadDone,
-                 weak_factory_.GetWeakPtr(), callback),
-      base::Bind(&ArcBluetoothBridge::OnGattReadError,
-                 weak_factory_.GetWeakPtr(), callback));
+  descriptor->ReadRemoteDescriptor(base::Bind(&OnGattReadDone, callback),
+                                   base::Bind(&OnGattReadError, callback));
 }
 
 void ArcBluetoothBridge::WriteGattDescriptor(
@@ -971,16 +979,14 @@ void ArcBluetoothBridge::WriteGattDescriptor(
   // TODO(http://crbug.com/622832)
   if (descriptor->GetUUID() ==
       BluetoothGattDescriptor::ClientCharacteristicConfigurationUuid()) {
-    OnGattWriteDone(callback);
+    OnGattOperationDone(callback);
     return;
   }
 
   descriptor->WriteRemoteDescriptor(
       value->value.To<std::vector<uint8_t>>(),
-      base::Bind(&ArcBluetoothBridge::OnGattWriteDone,
-                 weak_factory_.GetWeakPtr(), callback),
-      base::Bind(&ArcBluetoothBridge::OnGattWriteError,
-                 weak_factory_.GetWeakPtr(), callback));
+      base::Bind(&OnGattOperationDone, callback),
+      base::Bind(&OnGattOperationError, callback));
 }
 
 void ArcBluetoothBridge::OnGattNotifyStartDone(
@@ -991,17 +997,6 @@ void ArcBluetoothBridge::OnGattNotifyStartDone(
   callback.Run(mojom::BluetoothGattStatus::GATT_SUCCESS);
 }
 
-void ArcBluetoothBridge::OnGattNotifyStartError(
-    const RegisterForGattNotificationCallback& callback,
-    BluetoothGattService::GattErrorCode error_code) const {
-  callback.Run(mojo::ConvertTo<mojom::BluetoothGattStatus>(error_code));
-}
-
-void ArcBluetoothBridge::OnGattNotifyStopDone(
-    const DeregisterForGattNotificationCallback& callback) const {
-  callback.Run(mojom::BluetoothGattStatus::GATT_SUCCESS);
-}
-
 void ArcBluetoothBridge::RegisterForGattNotification(
     mojom::BluetoothAddressPtr remote_addr,
     mojom::BluetoothGattServiceIDPtr service_id,
@@ -1024,8 +1019,7 @@ void ArcBluetoothBridge::RegisterForGattNotification(
       base::Bind(&ArcBluetoothBridge::OnGattNotifyStartDone,
                  weak_factory_.GetWeakPtr(), callback,
                  characteristic->GetIdentifier()),
-      base::Bind(&ArcBluetoothBridge::OnGattNotifyStartError,
-                 weak_factory_.GetWeakPtr(), callback));
+      base::Bind(&OnGattOperationError, callback));
 }
 
 void ArcBluetoothBridge::DeregisterForGattNotification(
@@ -1050,8 +1044,7 @@ void ArcBluetoothBridge::DeregisterForGattNotification(
   std::unique_ptr<BluetoothGattNotifySession> notify =
       std::move(notification_session_[char_id_str]);
   notification_session_.erase(char_id_str);
-  notify->Stop(base::Bind(&ArcBluetoothBridge::OnGattNotifyStopDone,
-                          weak_factory_.GetWeakPtr(), callback));
+  notify->Stop(base::Bind(&OnGattOperationDone, callback));
 }
 
 void ArcBluetoothBridge::ReadRemoteRssi(
@@ -1063,30 +1056,118 @@ void ArcBluetoothBridge::ReadRemoteRssi(
   callback.Run(rssi);
 }
 
+template <class LocalGattAttribute>
+int32_t ArcBluetoothBridge::CreateGattAttributeHandle(
+    LocalGattAttribute* gatt_attr) {
+  DCHECK(CalledOnValidThread());
+  if (!gatt_attr)
+    return kInvalidGattAttributeHandle;
+  int32_t handle = next_gatt_server_attribute_handle();
+  const std::string& identifier = gatt_attr->GetIdentifier();
+  gatt_identifier_[handle] = identifier;
+  return handle;
+}
+
 void ArcBluetoothBridge::AddService(mojom::BluetoothGattServiceIDPtr service_id,
                                     int32_t num_handles,
-                                    const AddServiceCallback& callback) {}
+                                    const AddServiceCallback& callback) {
+  base::WeakPtr<BluetoothLocalGattService> service =
+      BluetoothLocalGattService::Create(
+          bluetooth_adapter_.get(), service_id->id->uuid.To<BluetoothUUID>(),
+          service_id->is_primary, nullptr /*included_service */,

[Luis Héctor Chávez, 2016/07/20 23:11:04]

nit: /* included service */

[puthik_chromium, 2016/07/21 00:05:04]

Done.

+          this /* delegate*/);
+  callback.Run(
+      CreateGattAttributeHandle<BluetoothLocalGattService>(service.get()));

[Luis Héctor Chávez, 2016/07/20 23:11:04]

This (and all other uses of CreateGattAttributeHandle) should also be
autodeduced their template types.

[puthik_chromium, 2016/07/21 00:05:04]

Done.

+}
 
 void ArcBluetoothBridge::AddCharacteristic(
     int32_t service_handle,
     mojom::BluetoothUUIDPtr uuid,
     int32_t properties,
     int32_t permissions,
-    const AddCharacteristicCallback& callback) {}
+    const AddCharacteristicCallback& callback) {
+  DCHECK(gatt_identifier_.find(service_handle) != gatt_identifier_.end());
+  base::WeakPtr<BluetoothLocalGattCharacteristic> characteristic =
+      BluetoothLocalGattCharacteristic::Create(
+          uuid.To<BluetoothUUID>(), properties, permissions,
+          bluetooth_adapter_->GetGattService(gatt_identifier_[service_handle]));
+  int32_t characteristic_handle =
+      CreateGattAttributeHandle<BluetoothLocalGattCharacteristic>(
+          characteristic.get());
+  last_characteristic_[service_handle] = characteristic_handle;
+  callback.Run(characteristic_handle);
+}
 
 void ArcBluetoothBridge::AddDescriptor(int32_t service_handle,
                                        mojom::BluetoothUUIDPtr uuid,
                                        int32_t permissions,
-                                       const AddDescriptorCallback& callback) {}
+                                       const AddDescriptorCallback& callback) {
+  // Chrome automatically adds a CCC Descriptor to a characteristic when needed.
+  // We will generate a bogus handle for Android.
+  if (uuid.To<BluetoothUUID>() ==
+      BluetoothGattDescriptor::ClientCharacteristicConfigurationUuid()) {
+    int32_t handle = next_gatt_server_attribute_handle();
+    callback.Run(handle);
+    return;
+  }
+
+  DCHECK(gatt_identifier_.find(service_handle) != gatt_identifier_.end());
+  BluetoothLocalGattService* service =
+      bluetooth_adapter_->GetGattService(gatt_identifier_[service_handle]);
+  DCHECK(service);
+  // Since the Android API does not give information about which characteristic
+  // is the parent of the new descriptor, we assume that it would be the last
+  // characteristic that was added to the given service. This matches the
+  // Android framework code at android/bluetooth/BluetoothGattServer.java#594.
+  // Link: https://goo.gl/cJZl1u
+  DCHECK(last_characteristic_.find(service_handle) !=
+         last_characteristic_.end());
+  int32_t last_characteristic_handle = last_characteristic_[service_handle];
+
+  DCHECK(gatt_identifier_.find(last_characteristic_handle) !=
+         gatt_identifier_.end());
+  BluetoothLocalGattCharacteristic* characteristic =
+      service->GetCharacteristic(gatt_identifier_[last_characteristic_handle]);
+  DCHECK(characteristic);
+
+  base::WeakPtr<BluetoothLocalGattDescriptor> descriptor =
+      BluetoothLocalGattDescriptor::Create(uuid.To<BluetoothUUID>(),
+                                           permissions, characteristic);
+  callback.Run(CreateGattAttributeHandle<BluetoothLocalGattDescriptor>(
+      descriptor.get()));
+}
 
 void ArcBluetoothBridge::StartService(int32_t service_handle,
-                                      const StartServiceCallback& callback) {}
+                                      const StartServiceCallback& callback) {
+  DCHECK(gatt_identifier_.find(service_handle) != gatt_identifier_.end());
+  BluetoothLocalGattService* service =
+      bluetooth_adapter_->GetGattService(gatt_identifier_[service_handle]);
+  DCHECK(service);
+  service->Register(base::Bind(&OnGattOperationDone, callback),
+                    base::Bind(&OnGattOperationError, callback));
+}
 
 void ArcBluetoothBridge::StopService(int32_t service_handle,
-                                     const StopServiceCallback& callback) {}
+                                     const StopServiceCallback& callback) {
+  DCHECK(gatt_identifier_.find(service_handle) != gatt_identifier_.end());
+  BluetoothLocalGattService* service =
+      bluetooth_adapter_->GetGattService(gatt_identifier_[service_handle]);
+  DCHECK(service);
+  service->Unregister(base::Bind(&OnGattOperationDone, callback),
+                      base::Bind(&OnGattOperationError, callback));
+}
 
 void ArcBluetoothBridge::DeleteService(int32_t service_handle,
-                                       const DeleteServiceCallback& callback) {}
+                                       const DeleteServiceCallback& callback) {
+  DCHECK(gatt_identifier_.find(service_handle) != gatt_identifier_.end());

[Luis Héctor Chávez, 2016/07/20 23:11:04]

Just for my peace of mind, can you add thread-checks in all the places you are
using |gatt_identifier_| and the other maps?

[puthik_chromium, 2016/07/21 00:05:04]

Done.

+  BluetoothLocalGattService* service =
+      bluetooth_adapter_->GetGattService(gatt_identifier_[service_handle]);
+  DCHECK(service);
+
+  service->Delete();
+  gatt_identifier_.erase(service_handle);
+  OnGattOperationDone(callback);
+}
 
 void ArcBluetoothBridge::SendIndication(
     int32_t attribute_handle,
@@ -1432,4 +1513,8 @@ bool ArcBluetoothBridge::CheckBluetoothInstanceVersion(
   return false;
 }
 
+bool ArcBluetoothBridge::CalledOnValidThread() {
+  return thread_checker_.CalledOnValidThread();
+}
+
 }  // namespace arc