| /* |
| * Copyright (C) 2018 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #ifndef ANDROID_HARDWARE_FACTORY_HAL_HIDL_H |
| #define ANDROID_HARDWARE_FACTORY_HAL_HIDL_H |
| |
| /** @file Library entry points to create the HAL factories. */ |
| |
| #include <media/audiohal/DevicesFactoryHalInterface.h> |
| #include <media/audiohal/EffectsFactoryHalInterface.h> |
| #include <utils/StrongPointer.h> |
| |
| #include <array> |
| #include <utility> |
| |
| namespace android { |
| |
| /** Supported HAL versions, in order of preference. |
| * Implementation should use specialize the `create*FactoryHal` for their version. |
| * Client should use `createPreferedImpl<*FactoryHal>()` to instantiate |
| * the preferred available impl. |
| */ |
| enum class AudioHALVersion { |
| V6_0, |
| V5_0, |
| V4_0, |
| V2_0, |
| end, // used for iterating over supported versions |
| }; |
| |
| /** Template function to fully specialized for each version and each Interface. */ |
| template <AudioHALVersion, class Interface> |
| sp<Interface> createFactoryHal(); |
| |
| /** @Return the preferred available implementation or nullptr if none are available. */ |
| template <class Interface, AudioHALVersion version = AudioHALVersion{}> |
| static sp<Interface> createPreferedImpl() { |
| if constexpr (version == AudioHALVersion::end) { |
| return nullptr; // tried all version, all returned nullptr |
| } else { |
| if (auto created = createFactoryHal<version, Interface>(); created != nullptr) { |
| return created; |
| } |
| |
| using Raw = std::underlying_type_t<AudioHALVersion>; // cast as enum class do not support ++ |
| return createPreferedImpl<Interface, AudioHALVersion(Raw(version) + 1)>(); |
| } |
| } |
| |
| |
| } // namespace android |
| |
| #endif // ANDROID_HARDWARE_FACTORY_HAL_HIDL_H |