fileIo.hpp

/*
 * CoDiPack, a Code Differentiation Package
 *
 * Copyright (C) 2015-2024 Chair for Scientific Computing (SciComp), University of Kaiserslautern-Landau
 * Homepage: http://scicomp.rptu.de
 * Contact:  Prof. Nicolas R. Gauger (codi@scicomp.uni-kl.de)
 *
 * Lead developers: Max Sagebaum, Johannes Blühdorn (SciComp, University of Kaiserslautern-Landau)
 *
 * This file is part of CoDiPack (http://scicomp.rptu.de/software/codi).
 *
 * CoDiPack is free software: you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * CoDiPack is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
 * See the GNU General Public License for more details.
 * You should have received a copy of the GNU
 * General Public License along with CoDiPack.
 * If not, see <http://www.gnu.org/licenses/>.
 *
 * For other licensing options please contact us.
 *
 * Authors:
 *  - SciComp, University of Kaiserslautern-Landau:
 *    - Max Sagebaum
 *    - Johannes Blühdorn
 *    - Former members:
 *      - Tim Albring
 */
 
#pragma once
 
#include <errno.h>
#include <stdio.h>
#include <string.h>
 
#include <iostream>
#include <string>
 
#include "../config.h"
#include "macros.hpp"
 
namespace codi {
 
  enum struct IoError {
    Mode,
    Open,
    Write,
    Read
  };
 
  struct IoException {
    public:
 
      std::string text;  
      IoError id;        
 
      IoException(IoError id, std::string const& text, bool appendErrno) : text(text), id(id) {
        if (appendErrno) {
          this->text += " (Internal error: ";
          this->text += strerror(errno);
          this->text += ")";
        }
      }
  };
 
  struct FileIo {
    private:
 
      FILE* fileHandle;  
      bool writeMode;    
 
    public:
 
      FileIo(std::string const& file, bool write) {
        writeMode = write;
        fileHandle = nullptr;
 
        if (write) {
          fileHandle = fopen(file.c_str(), "wb");
        } else {
          fileHandle = fopen(file.c_str(), "rb");
        }
 
        if (nullptr == fileHandle) {
          throw IoException(IoError::Open, "Could not open file: " + file, true);
        }
      }
 
      ~FileIo() {
        if (nullptr != fileHandle) {
          fclose(fileHandle);
        }
      }
 
      template<typename Data>
      void writeData(Data const* data, size_t const length) {
        if (writeMode) {
          size_t s = fwrite(data, sizeof(Data), length, fileHandle);
 
          if (s != length) {
            throw IoException(IoError::Read, "Wrong number of bytes written.", true);
          }
        } else {
          throw IoException(IoError::Mode, "Using write io handle in wrong mode.", false);
        }
      }
 
      template<typename Data>
      void readData(Data* data, size_t const length) {
        if (!writeMode) {
          size_t s = fread(data, sizeof(Data), length, fileHandle);
 
          if (s != length) {
            throw IoException(IoError::Read, "Wrong number of bytes read.", false);
          }
        } else {
          throw IoException(IoError::Mode, "Using read io handle in wrong mode.", false);
        }
      }
  };
}