binder: Add enum_range<Enum>
Native backends of AIDL enum types support a template variable for
enumerating all values of the type.
Bug: 143992652
Test: system/tools/aidl/runtests.sh
atest CtsNdkBinderTestCases
Change-Id: I3c3d24a6f24c4c02ac5c5b59bb0831c26f695dd2
diff --git a/libs/binder/include/binder/Enums.h b/libs/binder/include/binder/Enums.h
new file mode 100644
index 0000000..aec6f70
--- /dev/null
+++ b/libs/binder/include/binder/Enums.h
@@ -0,0 +1,41 @@
+/*
+ * Copyright (C) 2019 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.
+ */
+#pragma once
+
+#include <iterator>
+#include <type_traits>
+
+namespace android {
+
+namespace internal {
+
+// Never instantiated. Used as a placeholder for template variables.
+template <typename T>
+struct invalid_type;
+
+// AIDL generates specializations of this for enums.
+template <typename EnumType, typename = std::enable_if_t<std::is_enum<EnumType>::value>>
+constexpr invalid_type<EnumType> enum_values;
+} // namespace internal
+
+// Usage: for (const auto v : enum_range<EnumType>() ) { ... }
+template <typename EnumType, typename = std::enable_if_t<std::is_enum<EnumType>::value>>
+struct enum_range {
+ constexpr auto begin() const { return std::begin(internal::enum_values<EnumType>); }
+ constexpr auto end() const { return std::end(internal::enum_values<EnumType>); }
+};
+
+} // namespace android
\ No newline at end of file
diff --git a/libs/binder/ndk/include_ndk/android/binder_enums.h b/libs/binder/ndk/include_ndk/android/binder_enums.h
new file mode 100644
index 0000000..ee819c0
--- /dev/null
+++ b/libs/binder/ndk/include_ndk/android/binder_enums.h
@@ -0,0 +1,65 @@
+/*
+ * Copyright (C) 2019 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.
+ */
+
+/**
+ * @addtogroup NdkBinder
+ * @{
+ */
+
+/**
+ * @file binder_enums.h
+ * @brief Helpers for AIDL enum types.
+ */
+
+#pragma once
+
+#include <iterator>
+#include <type_traits>
+
+namespace ndk {
+
+namespace internal {
+/**
+ * Never instantiated. Used as a placeholder for template variables.
+ */
+template <typename T>
+struct invalid_type;
+
+/**
+ * AIDL generates specializations of this for enums.
+ */
+template <typename EnumType, typename = std::enable_if_t<std::is_enum<EnumType>::value>>
+constexpr invalid_type<EnumType> enum_values;
+} // namespace internal
+
+/**
+ * Iterable interface to enumerate all values of AIDL enum types.
+ */
+template <typename EnumType, typename = std::enable_if_t<std::is_enum<EnumType>::value>>
+struct enum_range {
+ /**
+ * Return an iterator pointing to the first enum value.
+ */
+ constexpr auto begin() const { return std::begin(internal::enum_values<EnumType>); }
+ /**
+ * Return an iterator pointing to one past the last enum value.
+ */
+ constexpr auto end() const { return std::end(internal::enum_values<EnumType>); }
+};
+
+} // namespace ndk
+
+/** @} */
\ No newline at end of file