Add a shared header lib for libbinder/libbinder_ndk
The new header lib will be shared by libbinder and libbinder_ndk.
We'll put shared functionality here.
For now, it contains ToString() which is used by AIDL-generated
parcelables for both C++ and NDK backends.
Bug: 179020493
Test: aidl_integration_test
Change-Id: I930a334fa6d6f1a7b38729f8df6bcdb202c9f19c
diff --git a/libs/binder/ndk/Android.bp b/libs/binder/ndk/Android.bp
index 82f3882..d76a1f9 100644
--- a/libs/binder/ndk/Android.bp
+++ b/libs/binder/ndk/Android.bp
@@ -129,6 +129,28 @@
],
}
+cc_library_headers {
+ name: "libbinder_headers_platform_shared",
+ export_include_dirs: ["include_cpp"],
+ vendor_available: true,
+ host_supported: true,
+ // TODO(b/153609531): remove when no longer needed.
+ native_bridge_supported: true,
+ target: {
+ darwin: {
+ enabled: false,
+ },
+ },
+ min_sdk_version: "29",
+ apex_available: [
+ "//apex_available:platform",
+ // TODO(b/166468760) remove these three
+ "com.android.media",
+ "com.android.media.swcodec",
+ "test_com.android.media.swcodec",
+ ],
+}
+
ndk_headers {
name: "libbinder_ndk_headers",
from: "include_ndk/android",
diff --git a/libs/binder/ndk/include_cpp/android/binder_to_string.h b/libs/binder/ndk/include_cpp/android/binder_to_string.h
new file mode 100644
index 0000000..bd51b11
--- /dev/null
+++ b/libs/binder/ndk/include_cpp/android/binder_to_string.h
@@ -0,0 +1,184 @@
+/*
+ * Copyright (C) 2021 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_to_string.h
+ * @brief Helper for parcelable.
+ */
+
+#pragma once
+
+#include <codecvt>
+#include <locale>
+#include <sstream>
+#include <string>
+#include <type_traits>
+
+#if __has_include(<android/binder_ibinder.h>)
+#include <android/binder_auto_utils.h>
+#include <android/binder_interface_utils.h>
+#include <android/binder_parcelable_utils.h>
+#define HAS_NDK_INTERFACE
+#else
+#include <binder/IBinder.h>
+#include <binder/IInterface.h>
+#include <binder/ParcelFileDescriptor.h>
+#include <binder/ParcelableHolder.h>
+#include <utils/String16.h>
+#include <utils/StrongPointer.h>
+#define HAS_CPP_INTERFACE
+#endif //_has_include
+
+namespace android {
+namespace internal {
+
+// ToString is a utility to generate string representation for various AIDL-supported types.
+template <typename _T>
+std::string ToString(const _T& t);
+
+namespace details {
+
+// Truthy if _T has toString() method.
+template <typename _T>
+class HasToStringMethod {
+ template <typename _U>
+ static auto _test(int) -> decltype(std::declval<_U>().toString(), std::true_type());
+ template <typename _U>
+ static std::false_type _test(...);
+
+ public:
+ enum { value = decltype(_test<_T>(0))::value };
+};
+
+// Truthy if _T has a overloaded toString(T)
+template <typename _T>
+class HasToStringFunction {
+ template <typename _U>
+ static auto _test(int) -> decltype(toString(std::declval<_U>()), std::true_type());
+ template <typename _U>
+ static std::false_type _test(...);
+
+ public:
+ enum { value = decltype(_test<_T>(0))::value };
+};
+
+// Truthy if _T is like a pointer
+template <typename _T>
+class IsPointerLike {
+ template <typename _U>
+ static auto _test(int) -> decltype(!std::declval<_U>(), *std::declval<_U>(), std::true_type());
+ template <typename _U>
+ static std::false_type _test(...);
+
+ public:
+ enum { value = decltype(_test<_T>(0))::value };
+};
+
+// Truthy if _T is like a container
+template <typename _T>
+class IsIterable {
+ template <typename _U>
+ static auto _test(int)
+ -> decltype(begin(std::declval<_U>()), end(std::declval<_U>()), std::true_type());
+ template <typename _U>
+ static std::false_type _test(...);
+
+ public:
+ enum { value = decltype(_test<_T>(0))::value };
+};
+
+template <typename _T>
+class ToEmptyString {
+ template <typename _U>
+ static std::enable_if_t<
+#ifdef HAS_NDK_INTERFACE
+ std::is_base_of_v<::ndk::ICInterface, _U> || std::is_same_v<::ndk::SpAIBinder, _U> ||
+ std::is_same_v<::ndk::ScopedFileDescriptor, _U> ||
+ std::is_same_v<::ndk::AParcelableHolder, _U>
+#else
+ std::is_base_of_v<IInterface, _U> || std::is_same_v<IBinder, _U> ||
+ std::is_same_v<os::ParcelFileDescriptor, _U> ||
+ std::is_same_v<os::ParcelableHolder, _U>
+#endif
+ ,
+ std::true_type>
+ _test(int);
+ template <typename _U>
+ static std::false_type _test(...);
+
+ public:
+ enum { value = decltype(_test<_T>(0))::value };
+};
+
+} // namespace details
+
+template <typename _T>
+std::string ToString(const _T& t) {
+ if constexpr (details::ToEmptyString<_T>::value) {
+ return "";
+ } else if constexpr (std::is_same_v<bool, _T>) {
+ return t ? "true" : "false";
+ } else if constexpr (std::is_same_v<char16_t, _T>) {
+ return std::wstring_convert<std::codecvt_utf8_utf16<char16_t>, char16_t>().to_bytes(t);
+ } else if constexpr (std::is_arithmetic_v<_T>) {
+ return std::to_string(t);
+ } else if constexpr (std::is_same_v<std::string, _T>) {
+ return t;
+#ifdef HAS_CPP_INTERFACE
+ } else if constexpr (std::is_same_v<String16, _T>) {
+ std::stringstream out;
+ out << t;
+ return out.str();
+#endif
+ } else if constexpr (details::HasToStringMethod<_T>::value) {
+ return t.toString();
+ } else if constexpr (details::HasToStringFunction<_T>::value) {
+ return toString(t);
+ } else if constexpr (details::IsIterable<_T>::value) {
+ std::stringstream out;
+ bool first = true;
+ out << "[";
+ for (const auto& e : t) {
+ if (first) {
+ first = false;
+ } else {
+ out << ", ";
+ }
+ // Use explicit type parameter in case deref of iterator has different type
+ // e.g. vector<bool>
+ out << ToString<typename _T::value_type>(e);
+ }
+ out << "]";
+ return out.str();
+ } else if constexpr (details::IsPointerLike<_T>::value) {
+ if (!t) return "(null)";
+ std::stringstream out;
+ out << ToString(*t);
+ return out.str();
+ } else {
+ return "{no toString() implemented}";
+ }
+}
+
+} // namespace internal
+} // namespace android
+
+/** @} */