// Copyright (c) 2012 The Chromium Authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. #ifndef MEDIA_BASE_BIT_READER_H_ #define MEDIA_BASE_BIT_READER_H_ #include #include #include "base/compiler_specific.h" #include "media/base/bit_reader_core.h" #include "media/base/media_export.h" namespace media { class MEDIA_EXPORT BitReader : private BitReaderCore::ByteStreamProvider { public: // Initialize the reader to start reading at |data|, |size| being size // of |data| in bytes. BitReader(const uint8_t* data, int size); BitReader(const BitReader&) = delete; BitReader& operator=(const BitReader&) = delete; ~BitReader() override; template bool ReadBits(int num_bits, T* out) { return bit_reader_core_.ReadBits(num_bits, out); } bool ReadFlag(bool* flag) { return bit_reader_core_.ReadFlag(flag); } // Read |num_bits| of binary data into |str|. |num_bits| must be a positive // multiple of 8. This is not efficient for extracting large strings. // If false is returned, |str| may not be valid. bool ReadString(int num_bits, std::string* str); bool SkipBits(int num_bits) { return bit_reader_core_.SkipBits(num_bits); } int bits_available() const { return initial_size_ * 8 - bits_read(); } int bits_read() const { return bit_reader_core_.bits_read(); } private: // BitReaderCore::ByteStreamProvider implementation. int GetBytes(int max_n, const uint8_t** out) override; // Total number of bytes that was initially passed to BitReader. const int initial_size_; // Pointer to the next unread byte in the stream. const uint8_t* data_; // Bytes left in the stream. int bytes_left_; BitReaderCore bit_reader_core_; }; } // namespace media #endif // MEDIA_BASE_BIT_READER_H_