buffer_reader.h

// Copyright 2014 Google LLC. All rights reserved.
//
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file or at
// https://developers.google.com/open-source/licenses/bsd
 
#ifndef PACKAGER_MEDIA_BASE_BUFFER_READER_H_
#define PACKAGER_MEDIA_BASE_BUFFER_READER_H_
 
#include <cstddef>
#include <cstdint>
#include <string>
#include <vector>
 
#include <packager/macros/classes.h>
 
namespace shaka {
namespace media {
 
class BufferReader {
 public:
  BufferReader(const uint8_t* buf, size_t size)
      : buf_(buf), size_(size), pos_(0) {}
  ~BufferReader() {}
 
  bool HasBytes(size_t count) { return pos() + count <= size(); }
 
  [[nodiscard]] bool Read1(uint8_t* v);
  [[nodiscard]] bool Read2(uint16_t* v);
  [[nodiscard]] bool Read2s(int16_t* v);
  [[nodiscard]] bool Read4(uint32_t* v);
  [[nodiscard]] bool Read4s(int32_t* v);
  [[nodiscard]] bool Read8(uint64_t* v);
  [[nodiscard]] bool Read8s(int64_t* v);
 
  [[nodiscard]] bool ReadNBytesInto8(uint64_t* v, size_t num_bytes);
  [[nodiscard]] bool ReadNBytesInto8s(int64_t* v, size_t num_bytes);
 
  [[nodiscard]] bool ReadToVector(std::vector<uint8_t>* t, size_t count);
  [[nodiscard]] bool ReadToString(std::string* str, size_t size);
 
  [[nodiscard]] bool ReadCString(std::string* str);
 
  [[nodiscard]] bool SkipBytes(size_t num_bytes);
 
  const uint8_t* data() const { return buf_; }
  size_t size() const { return size_; }
  void set_size(size_t size) { size_ = size; }
  size_t pos() const { return pos_; }
 
 private:
  // Internal implementation of multi-byte reads.
  template <typename T>
  [[nodiscard]] bool Read(T* t);
  template <typename T>
  [[nodiscard]] bool ReadNBytes(T* t, size_t num_bytes);
 
  const uint8_t* buf_;
  size_t size_;
  size_t pos_;
 
  DISALLOW_COPY_AND_ASSIGN(BufferReader);
};
 
}  // namespace media
}  // namespace shaka
 
#endif  // PACKAGER_MEDIA_BASE_BUFFER_READER_H_