1 /* 2 * Copyright 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_AAUDIO_SHARED_MEMORY_PARCELABLE_H 18 #define ANDROID_AAUDIO_SHARED_MEMORY_PARCELABLE_H 19 20 #include <stdint.h> 21 #include <sys/mman.h> 22 23 #include <android-base/unique_fd.h> 24 #include <binder/Parcel.h> 25 #include <binder/Parcelable.h> 26 27 namespace aaudio { 28 29 // Arbitrary limits for sanity checks. TODO remove after debugging. 30 #define MAX_SHARED_MEMORIES (32) 31 #define MAX_MMAP_OFFSET_BYTES (32 * 1024 * 8) 32 #define MAX_MMAP_SIZE_BYTES (32 * 1024 * 8) 33 34 /** 35 * This is a parcelable description of a shared memory referenced by a file descriptor. 36 * It may be divided into several regions. 37 * The memory can be shared using Binder or simply shared between threads. 38 */ 39 class SharedMemoryParcelable : public android::Parcelable { 40 public: 41 SharedMemoryParcelable(); 42 virtual ~SharedMemoryParcelable(); 43 44 /** 45 * Make a dup() of the fd and store it for later use. 46 * 47 * @param fd 48 * @param sizeInBytes 49 */ 50 void setup(const android::base::unique_fd& fd, int32_t sizeInBytes); 51 52 virtual android::status_t writeToParcel(android::Parcel* parcel) const override; 53 54 virtual android::status_t readFromParcel(const android::Parcel* parcel) override; 55 56 // mmap() shared memory 57 aaudio_result_t resolve(int32_t offsetInBytes, int32_t sizeInBytes, void **regionAddressPtr); 58 59 // munmap() any mapped memory 60 aaudio_result_t close(); 61 62 int32_t getSizeInBytes(); 63 64 void dump(); 65 66 protected: 67 68 #define MMAP_UNRESOLVED_ADDRESS reinterpret_cast<uint8_t*>(MAP_FAILED) 69 70 aaudio_result_t resolveSharedMemory(const android::base::unique_fd& fd); 71 72 android::base::unique_fd mFd; 73 int32_t mSizeInBytes = 0; 74 uint8_t *mResolvedAddress = MMAP_UNRESOLVED_ADDRESS; 75 76 private: 77 78 aaudio_result_t validate() const; 79 80 }; 81 82 } /* namespace aaudio */ 83 84 #endif //ANDROID_AAUDIO_SHARED_MEMORY_PARCELABLE_H 85
