1 /*
2  * Copyright (C) 2016 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #ifndef ANDROID_HIDL_PASSTHROUGH_SUPPORT_H
18 #define ANDROID_HIDL_PASSTHROUGH_SUPPORT_H
19 
20 #include <android/hidl/base/1.0/IBase.h>
21 
22 namespace android {
23 namespace hardware {
24 namespace details {
25 
26 /*
27  * Wrap the given interface with the lowest BsChild possible. Will return the
28  * argument directly if nullptr or isRemote().
29  *
30  * Note that 'static_cast<IFoo*>(wrapPassthrough(foo).get()) is guaranteed to work'
31  * assuming that foo is an instance of IFoo.
32  *
33  * TODO(b/33754152): calling this method multiple times should not re-wrap.
34  */
35 sp<::android::hidl::base::V1_0::IBase> wrapPassthroughInternal(
36     sp<::android::hidl::base::V1_0::IBase> iface);
37 
38 /**
39  * Helper method which provides reasonable code to wrapPassthroughInternal
40  * which can be used to call wrapPassthrough.
41  */
42 template <typename IType,
43           typename = std::enable_if_t<std::is_same<i_tag, typename IType::_hidl_tag>::value>>
wrapPassthrough(sp<IType> iface)44 sp<IType> wrapPassthrough(sp<IType> iface) {
45     return static_cast<IType*>(wrapPassthroughInternal(iface).get());
46 }
47 
48 }  // namespace details
49 }  // namespace hardware
50 }  // namespace android
51 
52 
53 #endif  // ANDROID_HIDL_PASSTHROUGH_SUPPORT_H
54