AidlConversion: Implement conversion between types from CPP and NDK
Implement universal conversion functions between types
from CPP and NDK backends generated from the same AIDL
definition. The conversion is implemented via marshalling
and unmarshalling. More performant conversions need to
be implemented manually.
Move enum converters from DeviceHalAidl to the new module.
Bug: 205884982
Test: atest audio_aidl_ndk_cpp_conversion_tests
(cherry picked from https://android-review.googlesource.com/q/commit:25bc9a2ac9c3ff1bc7d552c785b1d3048ac0303e)
Merged-In: I9c820d22c673381f2a2fa8c13bc938535fbe4467
Change-Id: I9c820d22c673381f2a2fa8c13bc938535fbe4467
diff --git a/media/audioaidlconversion/AidlConversionNdkCpp.cpp b/media/audioaidlconversion/AidlConversionNdkCpp.cpp
new file mode 100644
index 0000000..36f6128
--- /dev/null
+++ b/media/audioaidlconversion/AidlConversionNdkCpp.cpp
@@ -0,0 +1,128 @@
+/*
+ * Copyright (C) 2023 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.
+ */
+
+#include <algorithm>
+#include <type_traits>
+
+#define LOG_TAG "AidlConversionNdkCpp"
+#include <utils/Log.h>
+
+#include <android-base/expected.h>
+#include <android/binder_auto_utils.h>
+#include <android/binder_enums.h>
+#include <android/binder_parcel.h>
+#include <binder/Enums.h>
+#include <media/AidlConversionNdkCpp.h>
+#include <media/AidlConversionUtil.h>
+
+using aidl::android::aidl_utils::statusTFromBinderStatusT;
+
+namespace android {
+
+namespace {
+
+// cpp2ndk and ndk2cpp are universal converters which work for any type,
+// however they are not the most efficient way to convert due to extra
+// marshaling / unmarshaling step.
+
+template<typename NdkType, typename CppType>
+ConversionResult<NdkType> cpp2ndk(const CppType& cpp) {
+ Parcel cppParcel;
+ RETURN_IF_ERROR(cpp.writeToParcel(&cppParcel));
+ ::ndk::ScopedAParcel ndkParcel(AParcel_create());
+ const int32_t ndkParcelBegin = AParcel_getDataPosition(ndkParcel.get());
+ RETURN_IF_ERROR(statusTFromBinderStatusT(AParcel_unmarshal(
+ ndkParcel.get(), cppParcel.data(), cppParcel.dataSize())));
+ RETURN_IF_ERROR(statusTFromBinderStatusT(AParcel_setDataPosition(
+ ndkParcel.get(), ndkParcelBegin)));
+ NdkType ndk;
+ RETURN_IF_ERROR(statusTFromBinderStatusT(ndk.readFromParcel(ndkParcel.get())));
+ return ndk;
+}
+
+template<typename CppType, typename NdkType>
+ConversionResult<CppType> ndk2cpp(const NdkType& ndk) {
+ ::ndk::ScopedAParcel ndkParcel(AParcel_create());
+ RETURN_IF_ERROR(statusTFromBinderStatusT(ndk.writeToParcel(ndkParcel.get())));
+ const int32_t ndkParcelDataSize = AParcel_getDataSize(ndkParcel.get());
+ if (ndkParcelDataSize < 0) {
+ return base::unexpected(BAD_VALUE);
+ }
+ // Parcel does not expose its data in a mutable form, we have to use an intermediate buffer.
+ std::vector<uint8_t> parcelData(static_cast<size_t>(ndkParcelDataSize));
+ RETURN_IF_ERROR(statusTFromBinderStatusT(AParcel_marshal(
+ ndkParcel.get(), parcelData.data(), 0, ndkParcelDataSize)));
+ Parcel cppParcel;
+ RETURN_IF_ERROR(cppParcel.setData(parcelData.data(), parcelData.size()));
+ CppType cpp;
+ RETURN_IF_ERROR(cpp.readFromParcel(&cppParcel));
+ return cpp;
+}
+
+// cpp2ndk_Enum and ndk2cpp_Enum are more efficient implementations specifically for enums.
+
+template<typename OutEnum, typename OutEnumRange, typename InEnum>
+ ConversionResult<OutEnum> convertEnum(const OutEnumRange& range, InEnum e) {
+ using InIntType = std::underlying_type_t<InEnum>;
+ static_assert(std::is_same_v<InIntType, std::underlying_type_t<OutEnum>>);
+
+ InIntType inEnumIndex = static_cast<InIntType>(e);
+ OutEnum outEnum = static_cast<OutEnum>(inEnumIndex);
+ if (std::find(range.begin(), range.end(), outEnum) == range.end()) {
+ return base::unexpected(BAD_VALUE);
+ }
+ return outEnum;
+}
+
+template<typename NdkEnum, typename CppEnum>
+ ConversionResult<NdkEnum> cpp2ndk_Enum(CppEnum cpp) {
+ return convertEnum<NdkEnum>(::ndk::enum_range<NdkEnum>(), cpp);
+}
+
+template<typename CppEnum, typename NdkEnum>
+ ConversionResult<CppEnum> ndk2cpp_Enum(NdkEnum ndk) {
+ return convertEnum<CppEnum>(enum_range<CppEnum>(), ndk);
+}
+
+} // namespace
+
+#define GENERATE_CONVERTERS(packageName, className) \
+ ConversionResult<::aidl::packageName::className> cpp2ndk_##className( \
+ const ::packageName::className& cpp) { \
+ return cpp2ndk<::aidl::packageName::className>(cpp); \
+ } \
+ ConversionResult<::packageName::className> ndk2cpp_##className( \
+ const ::aidl::packageName::className& ndk) { \
+ return ndk2cpp<::packageName::className>(ndk); \
+ }
+
+#define GENERATE_ENUM_CONVERTERS(packageName, className) \
+ ConversionResult<::aidl::packageName::className> cpp2ndk_##className( \
+ const ::packageName::className& cpp) { \
+ return cpp2ndk_Enum<::aidl::packageName::className>(cpp); \
+ } \
+ ConversionResult<::packageName::className> ndk2cpp_##className( \
+ const ::aidl::packageName::className& ndk) { \
+ return ndk2cpp_Enum<::packageName::className>(ndk); \
+}
+
+GENERATE_CONVERTERS(android::media::audio::common, AudioFormatDescription);
+GENERATE_CONVERTERS(android::media::audio::common, AudioHalEngineConfig);
+GENERATE_CONVERTERS(android::media::audio::common, AudioMMapPolicyInfo);
+GENERATE_ENUM_CONVERTERS(android::media::audio::common, AudioMMapPolicyType);
+GENERATE_CONVERTERS(android::media::audio::common, AudioPort);
+
+} // namespace android