1 // Copyright (c) 2010 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef PDF_CHUNK_STREAM_H_ 6 #define PDF_CHUNK_STREAM_H_ 7 8 #include <stddef.h> 9 10 #include <map> 11 #include <vector> 12 13 namespace chrome_pdf { 14 15 // This class collects a chunks of data into one data stream. Client can check 16 // if data in certain range is available, and get missing chunks of data. 17 class ChunkStream { 18 public: 19 ChunkStream(); 20 ~ChunkStream(); 21 22 void Clear(); 23 24 void Preallocate(size_t stream_size); 25 size_t GetSize(); 26 27 bool WriteData(size_t offset, void* buffer, size_t size); 28 bool ReadData(size_t offset, size_t size, void* buffer) const; 29 30 // Returns vector of pairs where first is an offset, second is a size. 31 bool GetMissedRanges(size_t offset, size_t size, 32 std::vector<std::pair<size_t, size_t> >* ranges) const; 33 bool IsRangeAvailable(size_t offset, size_t size) const; 34 size_t GetFirstMissingByte() const; 35 36 size_t GetLastByteBefore(size_t offset) const; 37 size_t GetFirstByteAfter(size_t offset) const; 38 39 private: 40 std::vector<unsigned char> data_; 41 42 // Pair, first - begining of the chunk, second - size of the chunk. 43 std::map<size_t, size_t> chunks_; 44 }; 45 46 }; // namespace chrome_pdf 47 48 #endif 49
