1 /* 2 * Copyright (C) 2013, 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 LATINIME_MMAPPED_BUFFER_H 18 #define LATINIME_MMAPPED_BUFFER_H 19 20 #include <cstdint> 21 #include <memory> 22 23 #include "defines.h" 24 #include "utils/byte_array_view.h" 25 26 namespace latinime { 27 28 class MmappedBuffer { 29 public: 30 typedef std::unique_ptr<const MmappedBuffer> MmappedBufferPtr; 31 32 static MmappedBufferPtr openBuffer(const char *const path, 33 const int bufferOffset, const int bufferSize, const bool isUpdatable); 34 35 // Mmap entire file. 36 static MmappedBufferPtr openBuffer(const char *const path, const bool isUpdatable); 37 38 static MmappedBufferPtr openBuffer(const char *const dirPath, const char *const fileName, 39 const bool isUpdatable); 40 41 ~MmappedBuffer(); 42 43 ReadWriteByteArrayView getReadWriteByteArrayView() const { 44 return mByteArrayView; 45 } 46 47 ReadOnlyByteArrayView getReadOnlyByteArrayView() const { 48 return mByteArrayView.getReadOnlyView(); 49 } 50 51 AK_FORCE_INLINE bool isUpdatable() const { 52 return mIsUpdatable; 53 } 54 55 private: 56 AK_FORCE_INLINE MmappedBuffer(uint8_t *const buffer, const int bufferSize, 57 void *const mmappedBuffer, const int alignedSize, const int mmapFd, 58 const bool isUpdatable) 59 : mByteArrayView(buffer, bufferSize), mMmappedBuffer(mmappedBuffer), 60 mAlignedSize(alignedSize), mMmapFd(mmapFd), mIsUpdatable(isUpdatable) {} 61 62 // Empty file. We have to handle an empty file as a valid part of a dictionary. 63 AK_FORCE_INLINE MmappedBuffer(const bool isUpdatable) 64 : mByteArrayView(), mMmappedBuffer(nullptr), mAlignedSize(0), 65 mMmapFd(0), mIsUpdatable(isUpdatable) {} 66 67 DISALLOW_IMPLICIT_CONSTRUCTORS(MmappedBuffer); 68 69 const ReadWriteByteArrayView mByteArrayView; 70 void *const mMmappedBuffer; 71 const int mAlignedSize; 72 const int mMmapFd; 73 const bool mIsUpdatable; 74 }; 75 } 76 #endif /* LATINIME_MMAPPED_BUFFER_H */ 77
