fastpfor 0.9.0

FastPFOR lib with C++ Rust wrapper and pure Rust implementation
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/**
 * This code is released under the
 * Apache License Version 2.0 http://www.apache.org/licenses/.
 *
 * (c) Daniel Lemire, http://lemire.me/en/
 */

#ifndef MAROPUPARSER_H_
#define MAROPUPARSER_H_

#include "common.h"
#include <iostream>

namespace FastPForLib {

/**
 * This is just a bit of code to parse the binary files provided by the
 * Maropu-Open-Coders library at
 * http://integerencoding.isti.cnr.it/?page_id=8
 */
class MaropuGapReader {
public:
  MaropuGapReader(const std::string &filename)
      : mFilename(filename), fd(NULL) {}
  MaropuGapReader(const MaropuGapReader &mgr)
      : mFilename(mgr.mFilename), fd(NULL) {}
  MaropuGapReader &operator=(const MaropuGapReader &mgr) {
    close();
    mFilename = mgr.mFilename;
    return *this;
  }

  std::string mFilename;
  FILE *fd;

  ~MaropuGapReader() { close(); }

  // return false if no more data can be loaded
  template <class container> bool loadIntegers(container &buffer) {
    if (fd == NULL) {
      std::cerr << "You forgot to open the file." << std::endl;
      return false;
    }
    uint32_t number;
    size_t result = fread(&number, sizeof(number), 1, fd);
    if (result != 1) {
      return false;
    }
    buffer.resize(number);
    result = fread(&(buffer[0]), sizeof(uint32_t), buffer.size(), fd);
    if (result != buffer.size()) {
      std::cerr << "IO status: " << strerror(errno) << std::endl;
      std::cerr << "Error reading from file " << std::endl;
      throw std::runtime_error("bad read");
    }
    return true;
  }

  void open() {
    close();
    fd = ::fopen(mFilename.c_str(), "rb");
    if (fd == NULL) {
      std::cerr << "IO status: " << strerror(errno) << std::endl;
      std::cerr << "Can't open " << mFilename << std::endl;
      throw std::runtime_error("could not open temp file");
    }
    setvbuf(fd, NULL, _IOFBF, 1024 * 4); // large buffer
  }

  void close() {
    if (fd != NULL) {
      ::fclose(fd);
      fd = NULL;
    }
  }
};

} // namespace FastPForLib

#endif /* MAROPUPARSER_H_ */