ByteSource.h

#pragma once

namespace facebook { namespace wdt {

class ByteSource {
public:
  /// @return true iff no more data to read
  bool finished() const;

  /// @return true iff there was an error reading
  bool hasError() const;

  /**
   * Read chunk of data from the source and return a pointer to data and its
   * size. Memory is owned by the source. Subsequent calls to read() might
   * delete the previously read data so make sure to consume all data between
   * calls to read().
   *
   * @param size      will be set to number of bytes read (the source will
   *                  decide how much data to read at once)
   *
   * @return          pointer to the data read; in case of failure or EOF,
   *                  nullptr will be returned and size will be set to 0;
   *                  use finished() and hasError() members to distinguish
   *                  the two cases
   */
  char* read(size_t& size);
};

}}