Ytai Ben-Tsvi | 4659e18 | 2019-11-06 09:53:34 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2019 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_OS_HIDL_MEMORY_H |
| 18 | #define ANDROID_OS_HIDL_MEMORY_H |
| 19 | |
| 20 | #include <jni.h> |
| 21 | #include <hidl/HidlSupport.h> |
| 22 | |
| 23 | namespace android { |
| 24 | |
| 25 | // A utility class for handling the android.os.HidlMemory class from JNI code. |
| 26 | class JHidlMemory final { |
| 27 | public: |
| 28 | // Convert an android.os.HidlMemory object to its C++ counterpart, |
| 29 | // hardware::hidl_memory. |
| 30 | // No duplication of file descriptors is performed. |
| 31 | // The returned reference is owned by the underlying Java object. |
| 32 | // Returns nullptr if conversion cannot be done. |
| 33 | static const hardware::hidl_memory* fromJava(JNIEnv* env, |
| 34 | jobject jobj); |
| 35 | |
| 36 | // Convert a hardware::hidl_memory object to its Java counterpart, |
| 37 | // android.os.HidlMemory. |
| 38 | // No duplication of file descriptors is performed. |
| 39 | // Returns nullptr if conversion cannot be done. |
| 40 | static jobject toJava(JNIEnv* env, |
| 41 | const hardware::hidl_memory& cobj); |
| 42 | |
| 43 | ~JHidlMemory(); |
| 44 | |
| 45 | private: |
| 46 | // We store an instance of type JHidlMemory attached to every Java object |
| 47 | // of type HidlMemory, for holding any native context we need. This instance |
| 48 | // will get deleted when finalize() is called on the Java object. |
| 49 | // This method either extracts the native object from the Java object, or |
| 50 | // attached a new one if it doesn't yet exist. |
| 51 | static JHidlMemory* getNativeContext(JNIEnv* env, jobject obj); |
| 52 | |
| 53 | // Convert an android.os.HidlMemory object to its C++ counterpart, |
| 54 | // hardware::hidl_memory. |
| 55 | // No duplication of file descriptors is performed. |
| 56 | // IMPORTANT: caller is responsible to native_handle_delete() the handle of the |
| 57 | // returned object. This is due to an underlying limitation of the hidl_handle |
| 58 | // type, where ownership of the handle implies ownership of the fd and we don't |
| 59 | // want the latter. |
| 60 | // Returns nullptr if conversion cannot be done. |
| 61 | static std::unique_ptr<hardware::hidl_memory> javaToNative(JNIEnv* env, |
| 62 | jobject jobj); |
| 63 | |
| 64 | std::unique_ptr<hardware::hidl_memory> mObj; |
| 65 | }; |
| 66 | |
| 67 | int register_android_os_HidlMemory(JNIEnv* env); |
| 68 | |
| 69 | } // namespace android |
| 70 | |
| 71 | #endif //ANDROID_OS_HIDL_MEMORY_H |