vpIoTools.cpp

/****************************************************************************
 *
 * ViSP, open source Visual Servoing Platform software.
 * Copyright (C) 2005 - 2019 by Inria. All rights reserved.
 *
 * This software 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 2 of the License, or
 * (at your option) any later version.
 * See the file LICENSE.txt at the root directory of this source
 * distribution for additional information about the GNU GPL.
 *
 * For using ViSP with software that can not be combined with the GNU
 * GPL, please contact Inria about acquiring a ViSP Professional
 * Edition License.
 *
 * See http://visp.inria.fr for more information.
 *
 * This software was developed at:
 * Inria Rennes - Bretagne Atlantique
 * Campus Universitaire de Beaulieu
 * 35042 Rennes Cedex
 * France
 *
 * If you have questions regarding the use of this file, please contact
 * Inria at visp@inria.fr
 *
 * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
 * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 * Description:
 * Directory management.
 *
 * Authors:
 * Fabien Spindler
 *
 *****************************************************************************/

#include <algorithm>
#include <cmath>
#include <errno.h>
#include <fcntl.h>
#include <fstream>
#include <limits>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <visp3/core/vpDebug.h>
#include <visp3/core/vpIoException.h>
#include <visp3/core/vpIoTools.h>
#if !defined(_WIN32) && (defined(__unix__) || defined(__unix) || (defined(__APPLE__) && defined(__MACH__))) // UNIX
#include <dirent.h>
#include <unistd.h>
#elif defined(_WIN32)
#include <direct.h>
#include <windows.h>
#endif
#if !defined(_WIN32)
  #ifdef __ANDROID__
  // Like IOS, wordexp.cpp is not defined for Android
  #else
  #include <wordexp.h>
  #endif
#endif

#if defined(__APPLE__) && defined(__MACH__) // Apple OSX and iOS (Darwin)
#include <TargetConditionals.h>             // To detect OSX or IOS using TARGET_OS_IOS macro
#endif

#ifndef PATH_MAX
#  ifdef _MAX_PATH
#    define PATH_MAX _MAX_PATH
#  else
#    define PATH_MAX 1024
#  endif
#endif

// Detect endianness of the host machine
// Reference: http://www.boost.org/doc/libs/1_36_0/boost/detail/endian.hpp
#if defined(__GLIBC__)
#include <endian.h>
#if (__BYTE_ORDER == __LITTLE_ENDIAN)
#define VISP_LITTLE_ENDIAN
#elif (__BYTE_ORDER == __BIG_ENDIAN)
#define VISP_BIG_ENDIAN
#elif (__BYTE_ORDER == __PDP_ENDIAN)
// Currently not supported when reading / writing binary file
#define VISP_PDP_ENDIAN
//#error PDP endian is not supported. //Uncomment if needed/happens
#else
#error Unknown machine endianness detected.
#endif
#elif defined(_BIG_ENDIAN) && !defined(_LITTLE_ENDIAN) || defined(__BIG_ENDIAN__) && !defined(__LITTLE_ENDIAN__)
#define VISP_BIG_ENDIAN
#elif defined(_LITTLE_ENDIAN) && !defined(_BIG_ENDIAN) || defined(__LITTLE_ENDIAN__) && !defined(__BIG_ENDIAN__)
#define VISP_LITTLE_ENDIAN
#elif defined(__sparc) || defined(__sparc__) || defined(_POWER) || defined(__powerpc__) || defined(__ppc__) ||         \
    defined(__hpux) || defined(_MIPSEB) || defined(_POWER) || defined(__s390__)

#define VISP_BIG_ENDIAN
#elif defined(__i386__) || defined(__alpha__) || defined(__ia64) || defined(__ia64__) || defined(_M_IX86) ||           \
    defined(_M_IA64) || defined(_M_ALPHA) || defined(__amd64) || defined(__amd64__) || defined(_M_AMD64) ||            \
    defined(__x86_64) || defined(__x86_64__) || defined(_M_X64) || defined(__ANDROID__)
    // It appears that all Android systems are little endian.
    // Refer https://stackoverflow.com/questions/6212951/endianness-of-android-ndk
#define VISP_LITTLE_ENDIAN
#elif defined(WINRT) // For UWP
// Refer https://social.msdn.microsoft.com/Forums/en-US/04c92ef9-e38e-415f-8958-ec9f7c196fd3/arm-endianess-under-windows-mobile?forum=windowsmobiledev
#define VISP_LITTLE_ENDIAN
#else
#error Cannot detect host machine endianness.
#endif

std::string vpIoTools::baseName = "";
std::string vpIoTools::baseDir = "";
std::string vpIoTools::configFile = "";
std::vector<std::string> vpIoTools::configVars = std::vector<std::string>();
std::vector<std::string> vpIoTools::configValues = std::vector<std::string>();

namespace
{
// The following code is not working on iOS since wordexp() is not available
// The function is not used on Android
#if (TARGET_OS_IOS == 0) && !defined(__ANDROID__)
void replaceAll(std::string &str, const std::string &search, const std::string &replace)
{
  size_t start_pos = 0;
  while ((start_pos = str.find(search, start_pos)) != std::string::npos) {
    str.replace(start_pos, search.length(), replace);
    start_pos += replace.length(); // Handles case where 'replace' is a
                                   // substring of 'search'
  }
}
#endif

#ifdef VISP_BIG_ENDIAN
// Swap 16 bits by shifting to the right the first byte and by shifting to the
// left the second byte
uint16_t swap16bits(const uint16_t val)
{
  return (((val >> 8) & 0x00FF) | ((val << 8) & 0xFF00));
}

// Swap 32 bits by shifting to the right the first 2 bytes and by shifting to
// the left the last 2 bytes
uint32_t swap32bits(const uint32_t val)
{
  return (((val >> 24) & 0x000000FF) | ((val >> 8) & 0x0000FF00) | ((val << 8) & 0x00FF0000) |
          ((val << 24) & 0xFF000000));
}

// Swap a float, the union is necessary because of the representation of a
// float in memory in IEEE 754.
float swapFloat(const float f)
{
  union {
    float f;
    unsigned char b[4];
  } dat1, dat2;

  dat1.f = f;
  dat2.b[0] = dat1.b[3];
  dat2.b[1] = dat1.b[2];
  dat2.b[2] = dat1.b[1];
  dat2.b[3] = dat1.b[0];
  return dat2.f;
}

// Swap a double, the union is necessary because of the representation of a
// double in memory in IEEE 754.
double swapDouble(const double d)
{
  union {
    double d;
    unsigned char b[8];
  } dat1, dat2;

  dat1.d = d;
  dat2.b[0] = dat1.b[7];
  dat2.b[1] = dat1.b[6];
  dat2.b[2] = dat1.b[5];
  dat2.b[3] = dat1.b[4];
  dat2.b[4] = dat1.b[3];
  dat2.b[5] = dat1.b[2];
  dat2.b[6] = dat1.b[1];
  dat2.b[7] = dat1.b[0];
  return dat2.d;
}
#endif
}

const std::string &vpIoTools::getBuildInformation()
{
  static std::string build_info =
#include "version_string.inc"
      ;
  return build_info;
}

void vpIoTools::setBaseName(const std::string &s) { baseName = s; }
void vpIoTools::setBaseDir(const std::string &dir) { baseDir = dir + "/"; }
std::string vpIoTools::getBaseName() { return baseName; }
std::string vpIoTools::getFullName() { return baseDir + baseName; }

void vpIoTools::getUserName(std::string &username)
{
// With MinGW, UNIX and _WIN32 are defined
#if !defined(_WIN32) && (defined(__unix__) || defined(__unix) || (defined(__APPLE__) && defined(__MACH__))) // UNIX
  // Get the user name.
  char *_username = NULL;
  _username = ::getenv("LOGNAME");
  if (_username == NULL) {
    vpERROR_TRACE("Cannot get the username. Check your LOGNAME environment variable");
    throw(vpIoException(vpIoException::cantGetUserName, "Cannot get the username"));
  }
  username = _username;
#elif defined(_WIN32)
#if (!defined(WINRT))
  unsigned int info_buffer_size = 1024;
  TCHAR *infoBuf = new TCHAR[info_buffer_size];
  DWORD bufCharCount = (DWORD)info_buffer_size;
  // Get the user name.
  if (!GetUserName(infoBuf, &bufCharCount)) {
    delete[] infoBuf;
    throw(vpIoException(vpIoException::cantGetUserName, "Cannot get the username"));
  }
  username = infoBuf;
  delete[] infoBuf;
#else
  throw(vpIoException(vpIoException::cantGetUserName, "Cannot get the username: not implemented on Universal "
                                                      "Windows Platform"));
#endif
#endif
}
std::string vpIoTools::getUserName()
{
  std::string username;
#if !defined(_WIN32) && (defined(__unix__) || defined(__unix) || (defined(__APPLE__) && defined(__MACH__))) // UNIX
  // Get the user name.
  char *_username = NULL;
  _username = ::getenv("LOGNAME");
  if (_username == NULL) {
    vpERROR_TRACE("Cannot get the username. Check your LOGNAME environment variable");
    throw(vpIoException(vpIoException::cantGetUserName, "Cannot get the username"));
  }
  username = _username;
#elif defined(_WIN32)
#if (!defined(WINRT))
  unsigned int info_buffer_size = 1024;
  TCHAR *infoBuf = new TCHAR[info_buffer_size];
  DWORD bufCharCount = (DWORD)info_buffer_size;
  // Get the user name.
  if (!GetUserName(infoBuf, &bufCharCount)) {
    delete[] infoBuf;
    vpERROR_TRACE("Cannot get the username");
    throw(vpIoException(vpIoException::cantGetUserName, "Cannot get the username"));
  }
  username = infoBuf;
  delete[] infoBuf;
#else
  throw(vpIoException(vpIoException::cantGetUserName, "Cannot get the username: not implemented on Universal "
                                                      "Windows Platform"));
#endif
#endif
  return username;
}

std::string vpIoTools::getenv(const char *env)
{
#if defined(_WIN32) && defined(WINRT)
  throw(vpIoException(vpIoException::cantGetenv, "Cannot get the environment variable value: not "
                                                 "implemented on Universal Windows Platform"));
#else
  std::string value;
  // Get the environment variable value.
  char *_value = NULL;
  _value = ::getenv(env);
  if (_value == NULL) {
    throw(vpIoException(vpIoException::cantGetenv, "Cannot get the environment variable value"));
  }
  value = _value;

  return value;
#endif
}

std::string vpIoTools::getenv(const std::string &env) { return (vpIoTools::getenv(env.c_str())); }

void vpIoTools::getVersion(const std::string &version, unsigned int &major, unsigned int &minor, unsigned int &patch)
{
  if (version.size() == 0) {
    major = 0;
    minor = 0;
    patch = 0;
  } else {
    size_t major_pos = version.find('.');
    std::string major_str = version.substr(0, major_pos);
    major = (unsigned)atoi(major_str.c_str());

    if (major_pos != std::string::npos) {
      size_t minor_pos = version.find('.', major_pos + 1);
      std::string minor_str = version.substr(major_pos + 1, (minor_pos - (major_pos + 1)));
      minor = (unsigned)atoi(minor_str.c_str());

      if (minor_pos != std::string::npos) {
        std::string patch_str = version.substr(minor_pos + 1);
        patch = (unsigned)atoi(patch_str.c_str());
      } else {
        patch = 0;
      }
    } else {
      minor = 0;
      patch = 0;
    }
  }
}

bool vpIoTools::checkDirectory(const char *dirname)
{
#if !defined(_WIN32) && (defined(__unix__) || defined(__unix) || (defined(__APPLE__) && defined(__MACH__))) // UNIX
  struct stat stbuf;
#elif defined(_WIN32) && defined(__MINGW32__)
  struct stat stbuf;
#elif defined(_WIN32)
  struct _stat stbuf;
#endif

  if (dirname == NULL || dirname[0] == '\0') {
    return false;
  }

  std::string _dirname = path(dirname);

#if !defined(_WIN32) && (defined(__unix__) || defined(__unix) || (defined(__APPLE__) && defined(__MACH__))) // UNIX
  if (stat(_dirname.c_str(), &stbuf) != 0)
#elif defined(_WIN32) && defined(__MINGW32__)
  // Remove trailing separator character if any
  // AppVeyor: Windows 6.3.9600 AMD64 ; C:/MinGW/bin/g++.exe  (ver 5.3.0) ;
  // GNU Make 3.82.90 Built for i686-pc-mingw32
  if (!_dirname.empty() && _dirname.at(_dirname.size() - 1) == vpIoTools::separator)
    _dirname = _dirname.substr(0, _dirname.size() - 1);
  if (stat(_dirname.c_str(), &stbuf) != 0)
#elif defined(_WIN32)
  if (_stat(_dirname.c_str(), &stbuf) != 0)
#endif
  {
    return false;
  }
#if defined(_WIN32) || (defined(__unix__) || defined(__unix) || (defined(__APPLE__) && defined(__MACH__)))
  if ((stbuf.st_mode & S_IFDIR) == 0)
#endif
  {
    return false;
  }
#if !defined(_WIN32) && (defined(__unix__) || defined(__unix) || (defined(__APPLE__) && defined(__MACH__))) // UNIX
  if ((stbuf.st_mode & S_IWUSR) == 0)
#elif defined(_WIN32)
  if ((stbuf.st_mode & S_IWRITE) == 0)
#endif
  {
    return false;
  }
  return true;
}

bool vpIoTools::checkDirectory(const std::string &dirname) { return vpIoTools::checkDirectory(dirname.c_str()); }

// See:
// https://gist.github.com/JonathonReinhart/8c0d90191c38af2dcadb102c4e202950
int vpIoTools::mkdir_p(const char *path, const int mode)
{
  /* Adapted from http://stackoverflow.com/a/2336245/119527 */
  const size_t len = strlen(path);
  char _path[PATH_MAX];
  char *p = NULL;
  const char sep = vpIoTools::separator;

  std::fill(_path, _path + PATH_MAX, 0);

  errno = 0;
  if (len > sizeof(_path) - 1) {
    errno = ENAMETOOLONG;
    return -1;
  }
  /* Copy string so its mutable */
  strcpy(_path, path);

  /* Iterate over the string */
  for (p = _path + 1; *p; p++) { // path cannot be empty
    if (*p == sep) {
      /* Temporarily truncate */
      *p = '\0';

#if !defined(_WIN32) && (defined(__unix__) || defined(__unix) || (defined(__APPLE__) && defined(__MACH__)))
      if (mkdir(_path, (mode_t)mode) != 0)
#elif defined(_WIN32)
      (void)mode; // var not used
      if (!checkDirectory(_path) && _mkdir(_path) != 0)
#endif
      {
        if (errno != EEXIST)
          return -1;
      }
      *p = sep;
    }
  }

#if !defined(_WIN32) && (defined(__unix__) || defined(__unix) || (defined(__APPLE__) && defined(__MACH__)))
  if (mkdir(_path, (mode_t)mode) != 0)
#elif defined(_WIN32)
  if (_mkdir(_path) != 0)
#endif
  {
    if (errno != EEXIST)
      return -1;
  }

  return 0;
}

void vpIoTools::makeDirectory(const char *dirname)
{
#if ((!defined(__unix__) && !defined(__unix) && (!defined(__APPLE__) || !defined(__MACH__)))) && !defined(_WIN32)
  std::cerr << "Unsupported platform for vpIoTools::makeDirectory()!" << std::endl;
  return;
#endif

#if !defined(_WIN32) && (defined(__unix__) || defined(__unix) || (defined(__APPLE__) && defined(__MACH__))) // UNIX
  struct stat stbuf;
#elif defined(_WIN32) && defined(__MINGW32__)
  struct stat stbuf;
#elif defined(_WIN32)
  struct _stat stbuf;
#endif

  if (dirname == NULL || dirname[0] == '\0') {
    vpERROR_TRACE("invalid directory name\n");
    throw(vpIoException(vpIoException::invalidDirectoryName, "invalid directory name"));
  }

  std::string _dirname = path(dirname);

#if !defined(_WIN32) && (defined(__unix__) || defined(__unix) || (defined(__APPLE__) && defined(__MACH__))) // UNIX
  if (stat(_dirname.c_str(), &stbuf) != 0)
#elif defined(_WIN32) && defined(__MINGW32__)
  if (stat(_dirname.c_str(), &stbuf) != 0)
#elif defined(_WIN32)
  if (_stat(_dirname.c_str(), &stbuf) != 0)
#endif
  {
    if (vpIoTools::mkdir_p(_dirname.c_str(), 0755) != 0) {
      vpERROR_TRACE("unable to create directory '%s'\n", dirname);
      throw(vpIoException(vpIoException::cantCreateDirectory, "unable to create directory"));
    }

    vpDEBUG_TRACE(2, "has created directory '%s'\n", dirname);
  }

  if (checkDirectory(dirname) == false) {
    vpERROR_TRACE("unable to create directory '%s'\n", dirname);
    throw(vpIoException(vpIoException::cantCreateDirectory, "unable to create directory"));
  }
}

void vpIoTools::makeDirectory(const std::string &dirname)
{
  try {
    vpIoTools::makeDirectory(dirname.c_str());
  } catch (...) {
    vpERROR_TRACE("unable to create directory '%s'\n", dirname.c_str());
    throw(vpIoException(vpIoException::cantCreateDirectory, "unable to create directory"));
  }
}

bool vpIoTools::checkFilename(const char *filename)
{
#if !defined(_WIN32) && (defined(__unix__) || defined(__unix) || (defined(__APPLE__) && defined(__MACH__))) // UNIX
  struct stat stbuf;
#elif defined(_WIN32)
  struct _stat stbuf;
#endif

  if (filename == NULL || filename[0] == '\0') {
    return false;
  }

  std::string _filename = path(filename);
#if !defined(_WIN32) && (defined(__unix__) || defined(__unix) || (defined(__APPLE__) && defined(__MACH__))) // UNIX
  if (stat(_filename.c_str(), &stbuf) != 0)
#elif defined(_WIN32)
  if (_stat(_filename.c_str(), &stbuf) != 0)
#endif
  {
    return false;
  }
  if ((stbuf.st_mode & S_IFREG) == 0) {
    return false;
  }
#if !defined(_WIN32) && (defined(__unix__) || defined(__unix) || (defined(__APPLE__) && defined(__MACH__))) // UNIX
  if ((stbuf.st_mode & S_IRUSR) == 0)
#elif defined(_WIN32)
  if ((stbuf.st_mode & S_IREAD) == 0)
#endif
  {
    return false;
  }
  return true;
}

bool vpIoTools::checkFilename(const std::string &filename) { return vpIoTools::checkFilename(filename.c_str()); }

bool vpIoTools::copy(const char *src, const char *dst)
{
  // Check if we have to consider a file or a directory
  if (vpIoTools::checkFilename(src)) {
// std::cout << "copy file: " << src << " in " << dst << std::endl;
#if !defined(_WIN32) && (defined(__unix__) || defined(__unix) || (defined(__APPLE__) && defined(__MACH__))) // UNIX
#if TARGET_OS_IOS == 0 // The following code is not working on iOS since
                       // wordexp() is not available
    char cmd[FILENAME_MAX];
    int ret;
    sprintf(cmd, "cp -p %s %s", src, dst);
    ret = system(cmd);
    if (ret) {
    }; // to avoid a warning
    // std::cout << cmd << " return value: " << ret << std::endl;
    return true;
#else
    throw(vpIoException(vpException::fatalError, "Cannot copy %s in %s: not implemented on iOS Platform", src, dst));
#endif
#elif defined(_WIN32)
#if (!defined(WINRT))
    char cmd[FILENAME_MAX];
    int ret;
    std::string src_ = vpIoTools::path(src);
    std::string dst_ = vpIoTools::path(dst);
    sprintf(cmd, "copy %s %s", src_.c_str(), dst_.c_str());
    ret = system(cmd);
    if (ret) {
    }; // to avoid a warning
    // std::cout << cmd << " return value: " << ret << std::endl;
    return true;
#else
    throw(vpIoException(vpException::fatalError, "Cannot copy %s in %s: not implemented on Universal Windows Platform",
                        src, dst));
#endif
#endif
  } else if (vpIoTools::checkDirectory(src)) {
// std::cout << "copy directory: " << src << " in " << dst << std::endl;
#if !defined(_WIN32) && (defined(__unix__) || defined(__unix) || (defined(__APPLE__) && defined(__MACH__))) // UNIX
#if TARGET_OS_IOS == 0 // The following code is not working on iOS since
                       // wordexp() is not available
    char cmd[FILENAME_MAX];
    int ret;
    sprintf(cmd, "cp -p -r %s %s", src, dst);
    ret = system(cmd);
    if (ret) {
    }; // to avoid a warning
    // std::cout << cmd << " return value: " << ret << std::endl;
    return true;
#else
    throw(vpIoException(vpException::fatalError, "Cannot copy %s in %s: not implemented on iOS Platform", src, dst));
#endif
#elif defined(_WIN32)
#if (!defined(WINRT))
    char cmd[FILENAME_MAX];
    int ret;
    std::string src_ = vpIoTools::path(src);
    std::string dst_ = vpIoTools::path(dst);
    sprintf(cmd, "copy %s %s", src_.c_str(), dst_.c_str());
    ret = system(cmd);
    if (ret) {
    }; // to avoid a warning
    // std::cout << cmd << " return value: " << ret << std::endl;
    return true;
#else
    throw(vpIoException(vpException::fatalError, "Cannot copy %s in %s: not implemented on Universal Windows Platform",
                        src, dst));
#endif
#endif
  } else {
    std::cout << "Cannot copy: " << src << " in " << dst << std::endl;
    return false;
  }
}
bool vpIoTools::copy(const std::string &src, const std::string &dst)
{
  return vpIoTools::copy(src.c_str(), dst.c_str());
}

bool vpIoTools::remove(const char *file_or_dir)
{
  // Check if we have to consider a file or a directory
  if (vpIoTools::checkFilename(file_or_dir)) {
    // std::cout << "remove file: " << file_or_dir << std::endl;
    if (::remove(file_or_dir) != 0)
      return false;
    else
      return true;
  } else if (vpIoTools::checkDirectory(file_or_dir)) {
// std::cout << "remove directory: " << file_or_dir << std::endl;
#if !defined(_WIN32) && (defined(__unix__) || defined(__unix) || (defined(__APPLE__) && defined(__MACH__))) // UNIX
#if TARGET_OS_IOS == 0 // The following code is not working on iOS since
                       // wordexp() is not available
    char cmd[FILENAME_MAX];
    sprintf(cmd, "rm -rf \"%s\"", file_or_dir);
    int ret = system(cmd);
    if (ret) {
    }; // to avoid a warning
    // std::cout << cmd << " return value: " << ret << std::endl;
    return true;
#else
    throw(vpIoException(vpException::fatalError, "Cannot remove %s: not implemented on iOS Platform", file_or_dir));
#endif
#elif defined(_WIN32)
#if (!defined(WINRT))
    char cmd[FILENAME_MAX];
    std::string file_or_dir_ = vpIoTools::path(file_or_dir);
    sprintf(cmd, "rmdir /S /Q %s", file_or_dir_.c_str());
    int ret = system(cmd);
    if (ret) {
    }; // to avoid a warning
    // std::cout << cmd << " return value: " << ret << std::endl;
    return true;
#else
    throw(vpIoException(vpException::fatalError, "Cannot remove %s: not implemented on Universal Windows Platform",
                        file_or_dir));
#endif
#endif
  } else {
    std::cout << "Cannot remove: " << file_or_dir << std::endl;
    return false;
  }
}
bool vpIoTools::remove(const std::string &file_or_dir) { return vpIoTools::remove(file_or_dir.c_str()); }

bool vpIoTools::rename(const char *oldfilename, const char *newfilename)
{
  if (::rename(oldfilename, newfilename) != 0)
    return false;
  else
    return true;
}

bool vpIoTools::rename(const std::string &oldfilename, const std::string &newfilename)
{
  return vpIoTools::rename(oldfilename.c_str(), newfilename.c_str());
}

std::string vpIoTools::path(const char *pathname)
{
  std::string path(pathname);

#if defined(_WIN32)
  for (unsigned int i = 0; i < path.length(); i++)
    if (path[i] == '/')
      path[i] = '\\';
#elif defined(__unix__) || defined(__unix) || (defined(__APPLE__) && defined(__MACH__))
  for (unsigned int i = 0; i < path.length(); i++)
    if (path[i] == '\\')
      path[i] = '/';
#if TARGET_OS_IOS == 0 // The following code is not working on iOS and android since
                       // wordexp() is not available
  #ifdef __ANDROID__
  // Do nothing
  #else
    wordexp_t exp_result;

    // escape quote character
    replaceAll(path, "'", "'\\''");
    // add quotes to handle special characters like parentheses and spaces
    wordexp(std::string("'" + path + "'").c_str(), &exp_result, 0);
    path = exp_result.we_wordc == 1 ? exp_result.we_wordv[0] : "";
    wordfree(&exp_result);
  #endif
#endif
#endif

  return path;
}

std::string vpIoTools::path(const std::string &pathname) { return path(pathname.c_str()); }

bool vpIoTools::loadConfigFile(const std::string &confFile)
{
  configFile = path(confFile);
  configVars.clear();
  configValues.clear();
  std::ifstream confContent(configFile.c_str(), std::ios::in);

  if (confContent.is_open()) {
    std::string line, var, val;
    long unsigned int k;
    int c;
    std::string stop[3] = {" ", "\t", "#"};
    while (std::getline(confContent, line)) {
      if ((line.compare(0, 1, "#") != 0) && (line.size() > 2)) {
        try {
          // name of the variable
          k = (unsigned long)line.find(" ");
          var = line.substr(0, k);
          // look for the end of the actual value
          c = 200;
          for (unsigned i = 0; i < 3; ++i)
            c = vpMath::minimum(c, (int)line.find(stop[i], k + 1));
          if (c == -1)
            c = (int)line.size();
          long unsigned int c_ = (long unsigned int)c;
          val = line.substr(k + 1, c_ - k - 1);
          configVars.push_back(var);
          configValues.push_back(val);
        } catch (...) {
        }
      }
    }
    confContent.close();
  } else {
    return false;
  }
  return true;
}

bool vpIoTools::readConfigVar(const std::string &var, float &value)
{
  bool found = false;
  for (unsigned int k = 0; k < configVars.size() && found == false; ++k) {
    if (configVars[k] == var) {
      if (configValues[k].compare("PI") == 0)
        value = (float)M_PI;
      else if (configValues[k].compare("PI/2") == 0)
        value = (float)(M_PI / 2.0);
      else if (configValues[k].compare("-PI/2") == 0)
        value = (float)(-M_PI / 2.0);
      else
        value = (float)atof(configValues[k].c_str());
      found = true;
    }
  }
  if (found == false)
    std::cout << var << " not found in config file" << std::endl;
  return found;
}
bool vpIoTools::readConfigVar(const std::string &var, double &value)
{
  bool found = false;
  for (unsigned int k = 0; k < configVars.size() && found == false; ++k) {
    if (configVars[k] == var) {
      if (configValues[k].compare("PI") == 0)
        value = M_PI;
      else if (configValues[k].compare("PI/2") == 0)
        value = M_PI / 2;
      else if (configValues[k].compare("-PI/2") == 0)
        value = -M_PI / 2;
      else
        value = atof(configValues[k].c_str());
      found = true;
    }
  }
  if (found == false)
    std::cout << var << " not found in config file" << std::endl;
  return found;
}

bool vpIoTools::readConfigVar(const std::string &var, int &value)
{
  bool found = false;
  for (unsigned int k = 0; k < configVars.size() && found == false; ++k) {
    if (configVars[k] == var) {
      value = atoi(configValues[k].c_str());
      found = true;
    }
  }
  if (found == false)
    std::cout << var << " not found in config file" << std::endl;
  return found;
}

bool vpIoTools::readConfigVar(const std::string &var, unsigned int &value)
{
  int v = 0;
  bool found = readConfigVar(var, v);
  value = (unsigned int)v;
  return found;
}

bool vpIoTools::readConfigVar(const std::string &var, bool &value)
{
  int v = 0;
  bool found = readConfigVar(var, v);
  value = (v != 0);
  return found;
}

bool vpIoTools::readConfigVar(const std::string &var, vpColor &value)
{
  unsigned int v = 0;
  bool found = readConfigVar(var, v);
  value = vpColor::getColor(v);
  return found;
}

bool vpIoTools::readConfigVar(const std::string &var, std::string &value)
{
  bool found = false;
  for (unsigned int k = 0; k < configVars.size() && found == false; ++k) {
    if (configVars[k] == var) {
      value = configValues[k];
      found = true;
    }
  }
  if (found == false)
    std::cout << var << " not found in config file" << std::endl;
  return found;
}

bool vpIoTools::readConfigVar(const std::string &var, vpArray2D<double> &value, const unsigned int &nCols,
                              const unsigned int &nRows)
{
  bool found = false;
  std::string nb;
  for (unsigned int k = 0; k < configVars.size() && found == false; ++k) {
    if (configVars[k] == var) {
      found = true;
      // resize or not
      if (nCols != 0 && nRows != 0)
        value.resize(nRows, nCols);
      size_t ind = 0, ind2;
      for (unsigned int i = 0; i < value.getRows(); ++i)
        for (unsigned int j = 0; j < value.getCols(); ++j) {
          ind2 = configValues[k].find(",", ind);
          nb = configValues[k].substr(ind, ind2 - ind);
          if (nb.compare("PI") == 0)
            value[i][j] = M_PI;
          else if (nb.compare("PI/2") == 0)
            value[i][j] = M_PI / 2;
          else if (nb.compare("-PI/2") == 0)
            value[i][j] = -M_PI / 2;
          else
            value[i][j] = atof(nb.c_str());
          ind = ind2 + 1;
        }
    }
  }
  if (found == false)
    std::cout << var << " not found in config file" << std::endl;
  return found;
}

// construct experiment filename & path

void vpIoTools::addNameElement(const std::string &strTrue, const bool &cond, const std::string &strFalse)
{
  if (cond)
    baseName += "_" + strTrue;
  else if (strFalse != "")
    baseName += "_" + strFalse;
}

void vpIoTools::addNameElement(const std::string &strTrue, const double &val)
{
  // if(val != 0.)
  if (std::fabs(val) < std::numeric_limits<double>::epsilon()) {
    char valC[256];
    sprintf(valC, "%.3f", val);
    std::string valS(valC);
    baseName += "_" + strTrue + valS;
  }
}

void vpIoTools::createBaseNamePath(const bool &empty)
{
  if (vpIoTools::checkDirectory(baseDir + baseName) == false) {
    vpIoTools::makeDirectory(baseDir + baseName);
    std::cout << "creating directory " + baseDir + baseName << std::endl;
  } else {
    if (empty) {
      std::cout << "emptying directory " + baseDir + baseName << std::endl;
      vpIoTools::remove(baseDir + baseName + "/*");
    }
  }
}

void vpIoTools::saveConfigFile(const bool &actuallySave)
{
  if (actuallySave) {
    std::string dest = baseDir + "/" + baseName + "_config.txt";
    // file copy
    vpIoTools::copy(configFile, dest);
  }
}

std::string vpIoTools::getViSPImagesDataPath()
{
  std::string data_path;
  std::string file_to_test("mbt/cube.cao");
  std::string filename;
#if !defined(_WIN32) && (defined(__unix__) || defined(__unix) || (defined(__APPLE__) && defined(__MACH__))) // UNIX
  // Test if visp-images-data package is u-installed (Ubuntu and Debian)
  data_path = "/usr/share/visp-images-data/ViSP-images";
  filename = data_path + "/" + file_to_test;
  if (vpIoTools::checkFilename(filename))
    return data_path;
  data_path = "/usr/share/visp-images-data/visp-images";
  filename = data_path + "/" + file_to_test;
  if (vpIoTools::checkFilename(filename))
    return data_path;
#endif
  // Test if VISP_INPUT_IMAGE_PATH env var is set
  try {
    data_path = vpIoTools::getenv("VISP_INPUT_IMAGE_PATH");
    filename = data_path + "/" + file_to_test;
    if (vpIoTools::checkFilename(filename))
      return data_path;
    data_path = vpIoTools::getenv("VISP_INPUT_IMAGE_PATH") + "/ViSP-images";
    filename = data_path + "/" + file_to_test;
    if (vpIoTools::checkFilename(filename))
      return data_path;
    data_path = vpIoTools::getenv("VISP_INPUT_IMAGE_PATH") + "/visp-images";
    filename = data_path + "/" + file_to_test;
    if (vpIoTools::checkFilename(filename))
      return data_path;
  } catch (...) {
  }
  data_path = "";
  return data_path;
}

std::string vpIoTools::getFileExtension(const std::string &pathname, const bool checkFile)
{
  if (checkFile && (vpIoTools::checkDirectory(pathname) || !vpIoTools::checkFilename(pathname))) {
    return "";
  }

#if defined(_WIN32)
  std::string sep = "\\";
  std::string altsep = "/";
  std::string extsep = ".";
#else
  // On Unix, or on the Mac
  std::string sep = "/";
  std::string altsep = "";
  std::string extsep = ".";
#endif

  // Python 2.7.8 module.
  //# Split a path in root and extension.
  //# The extension is everything starting at the last dot in the last
  //# pathname component; the root is everything before that.
  //# It is always true that root + ext == p.
  //
  //# Generic implementation of splitext, to be parametrized with
  //# the separators
  // def _splitext(p, sep, altsep, extsep):
  //    """Split the extension from a pathname.
  //
  //    Extension is everything from the last dot to the end, ignoring
  //    leading dots.  Returns "(root, ext)"; ext may be empty."""
  //
  //    sepIndex = p.rfind(sep)
  //    if altsep:
  //        altsepIndex = p.rfind(altsep)
  //        sepIndex = max(sepIndex, altsepIndex)
  //
  //    dotIndex = p.rfind(extsep)
  //    if dotIndex > sepIndex:
  //        # skip all leading dots
  //        filenameIndex = sepIndex + 1
  //        while filenameIndex < dotIndex:
  //            if p[filenameIndex] != extsep:
  //                return p[:dotIndex], p[dotIndex:]
  //            filenameIndex += 1
  //
  //    return p, ''

  int sepIndex = (int)pathname.rfind(sep);
  if (!altsep.empty()) {
    int altsepIndex = (int)pathname.rfind(altsep);
    sepIndex = ((std::max))(sepIndex, altsepIndex);
  }

  size_t dotIndex = pathname.rfind(extsep);
  if (dotIndex != std::string::npos) {
    // The extsep character exists
    if ((sepIndex != (int)std::string::npos && (int)dotIndex > sepIndex) || sepIndex == (int)std::string::npos) {
      if (sepIndex == (int)std::string::npos) {
        sepIndex = -1;
      }
      size_t filenameIndex = (size_t)(sepIndex + 1);

      while (filenameIndex < dotIndex) {
        if (pathname.compare(filenameIndex, 1, extsep) != 0) {
          return pathname.substr(dotIndex);
        }
        filenameIndex++;
      }
    }
  }

  return "";
}

std::string vpIoTools::getName(const std::string &pathname)
{
  if (pathname.size() > 0) {
    std::string convertedPathname = vpIoTools::path(pathname);

    size_t index = convertedPathname.find_last_of(vpIoTools::separator);
    if (index != std::string::npos) {
      return convertedPathname.substr(index + 1);
    }

    return convertedPathname;
  }

  return "";
}

std::string vpIoTools::getNameWE(const std::string &pathname)
{
  std::string name = vpIoTools::getName(pathname);
  size_t found = name.find_last_of(".");
  std::string name_we = name.substr(0, found);
  return name_we;
}

std::string vpIoTools::getParent(const std::string &pathname)
{
  if (pathname.size() > 0) {
    std::string convertedPathname = vpIoTools::path(pathname);

    size_t index = convertedPathname.find_last_of(vpIoTools::separator);
    if (index != std::string::npos) {
      return convertedPathname.substr(0, index);
    }
  }

  return "";
}

std::string vpIoTools::getAbsolutePathname(const std::string &pathname)
{

#if !defined(_WIN32) && (defined(__unix__) || defined(__unix) || (defined(__APPLE__) && defined(__MACH__))) // UNIX
  std::string real_path_str = pathname;
  char *real_path = realpath(pathname.c_str(), NULL);

  if (real_path != NULL) {
    real_path_str = real_path;
    free(real_path);
  }
  return real_path_str;
#elif defined(_WIN32)
#if (!defined(WINRT))
  std::string real_path_str = pathname;
  DWORD retval = 0;
  TCHAR buffer[4096] = TEXT("");

  retval = GetFullPathName(pathname.c_str(), 4096, buffer, 0);
  if (retval != 0) {
    real_path_str = buffer;
  }
  return real_path_str;
#else
  throw(vpIoException(vpException::fatalError,
                      "Cannot get absolute path of %s: not implemented on "
                      "Universal Windows Platform",
                      pathname.c_str()));
#endif
#endif
}

std::string vpIoTools::createFilePath(const std::string &parent, const std::string &child)
{
  if (child.size() == 0 && parent.size() == 0) {
    return "";
  }

  if (child.size() == 0) {
    return vpIoTools::path(parent);
  }

  if (parent.size() == 0) {
    return vpIoTools::path(child);
  }

  std::string convertedParent = vpIoTools::path(parent);
  std::string convertedChild = vpIoTools::path(child);

  std::stringstream ss;
  ss << vpIoTools::separator;
  std::string stringSeparator;
  ss >> stringSeparator;

  std::string lastConvertedParentChar = convertedParent.substr(convertedParent.size() - 1);
  std::string firstConvertedChildChar = convertedChild.substr(0, 1);

  if (lastConvertedParentChar == stringSeparator) {
    convertedParent = convertedParent.substr(0, convertedParent.size() - 1);
  }

  if (firstConvertedChildChar == stringSeparator) {
    convertedChild = convertedChild.substr(1);
  }

  return std::string(convertedParent + vpIoTools::separator + convertedChild);
}

bool vpIoTools::isAbsolutePathname(const std::string &pathname)
{
  //# Inspired by the Python 2.7.8 module.
  //# Return whether a path is absolute.
  //# Trivial in Posix, harder on the Mac or MS-DOS.
  //# For DOS it is absolute if it starts with a slash or backslash (current
  //# volume), or if a pathname after the volume letter and colon / UNC
  // resource # starts with a slash or backslash.
  //
  // def isabs(s):
  //    """Test whether a path is absolute"""
  //    s = splitdrive(s)[1]
  //    return s != '' and s[:1] in '/\\'
  std::string path = splitDrive(pathname).second;
  return path.size() > 0 && (path.substr(0, 1) == "/" || path.substr(0, 1) == "\\");
}

bool vpIoTools::isSamePathname(const std::string &pathname1, const std::string &pathname2)
{
  // Normalize path
  std::string path1_normalize = vpIoTools::path(pathname1);
  std::string path2_normalize = vpIoTools::path(pathname2);

  // Get absolute path
  path1_normalize = vpIoTools::getAbsolutePathname(path1_normalize);
  path2_normalize = vpIoTools::getAbsolutePathname(path2_normalize);

  return (path1_normalize == path2_normalize);
}

std::pair<std::string, std::string> vpIoTools::splitDrive(const std::string &pathname)
{
//# Split a path in a drive specification (a drive letter followed by a
//# colon) and the path specification.
//# It is always true that drivespec + pathspec == p
// def splitdrive(p):
//    """Split a pathname into drive/UNC sharepoint and relative path
//    specifiers. Returns a 2-tuple (drive_or_unc, path); either part may be
//    empty.
//
//    If you assign
//        result = splitdrive(p)
//    It is always true that:
//        result[0] + result[1] == p
//
//    If the path contained a drive letter, drive_or_unc will contain
//    everything up to and including the colon.  e.g. splitdrive("c:/dir")
//    returns ("c:", "/dir")
//
//    If the path contained a UNC path, the drive_or_unc will contain the host
//    name and share up to but not including the fourth directory separator
//    character. e.g. splitdrive("//host/computer/dir") returns
//    ("//host/computer", "/dir")
//
//    Paths cannot contain both a drive letter and a UNC path.
//
//    """
//    if len(p) > 1:
//        normp = p.replace(altsep, sep)
//        if (normp[0:2] == sep*2) and (normp[2] != sep):
//            # is a UNC path:
//            # vvvvvvvvvvvvvvvvvvvv drive letter or UNC path
//            # \\machine\mountpoint\directory\etc\...
//            #           directory ^^^^^^^^^^^^^^^
//            index = normp.find(sep, 2)
//            if index == -1:
//                return '', p
//            index2 = normp.find(sep, index + 1)
//            # a UNC path can't have two slashes in a row
//            # (after the initial two)
//            if index2 == index + 1:
//                return '', p
//            if index2 == -1:
//                index2 = len(p)
//            return p[:index2], p[index2:]
//        if normp[1] == ':':
//            return p[:2], p[2:]
//    return '', p

// On Unix, the drive is always empty.
// On the Mac, the drive is always empty (don't use the volume name -- it
// doesn't have the same  syntactic and semantic oddities as DOS drive
// letters, such as there being a separate current directory per drive).
#if !defined(_WIN32) && (defined(__unix__) || defined(__unix) || (defined(__APPLE__) && defined(__MACH__)))
  return std::pair<std::string, std::string>("", pathname);
#else
  const std::string sep = "\\";
  const std::string sepsep = "\\\\";
  const std::string altsep = "/";

  if (pathname.size() > 1) {
    std::string normPathname = pathname;
    std::replace(normPathname.begin(), normPathname.end(), *altsep.c_str(), *sep.c_str());

    if (normPathname.substr(0, 2) == sepsep && normPathname.substr(2, 1) != sep) {
      // is a UNC path:
      // vvvvvvvvvvvvvvvvvvvv drive letter or UNC path
      // \\machine\mountpoint\directory\etc\...
      //           directory ^^^^^^^^^^^^^^^
      size_t index = normPathname.find(sep, 2);
      if (index == std::string::npos) {
        return std::pair<std::string, std::string>("", pathname);
      }

      size_t index2 = normPathname.find(sep, index + 1);
      //# a UNC path can't have two slashes in a row
      //# (after the initial two)
      if (index2 == index + 1) {
        return std::pair<std::string, std::string>("", pathname);
      }

      if (index2 == std::string::npos) {
        index2 = pathname.size();
      }

      return std::pair<std::string, std::string>(pathname.substr(0, index2), pathname.substr(index2));
    }

    if (normPathname[1] == ':') {
      return std::pair<std::string, std::string>(pathname.substr(0, 2), pathname.substr(2));
    }
  }

  return std::pair<std::string, std::string>("", pathname);
#endif
}

std::vector<std::string> vpIoTools::splitChain(const std::string &chain, const std::string &sep)
{
  size_t startIndex = 0;

  std::string chainToSplit = chain;
  std::vector<std::string> subChain;
  size_t sepIndex = chainToSplit.find(sep);

  while (sepIndex != std::string::npos) {
    std::string sub = chainToSplit.substr(startIndex, sepIndex);
    if (!sub.empty())
      subChain.push_back(sub);
    chainToSplit = chainToSplit.substr(sepIndex + 1, chain.size() - 1);

    sepIndex = chainToSplit.find(sep);
  }
  if (!chainToSplit.empty())
    subChain.push_back(chainToSplit);

  return subChain;
}

std::vector<std::string> vpIoTools::getDirFiles(const std::string &pathname)
{

  if (!checkDirectory(pathname)) {
    throw(vpIoException(vpException::fatalError, "Directory %s doesn't exist'", pathname.c_str()));
  }
  std::string dirName = path(pathname);

#if !defined(_WIN32) && (defined(__unix__) || defined(__unix) || (defined(__APPLE__) && defined(__MACH__))) // UNIX

  std::vector<std::string> files;
  struct dirent **list = NULL;
  int filesCount = scandir(dirName.c_str(), &list, NULL, NULL);
  if (filesCount == -1) {
    throw(vpIoException(vpException::fatalError, "Cannot read files of directory %s", dirName.c_str()));
  }
  for (int i = 0; i < filesCount; i++) {
    std::string fileName = list[i]->d_name;
    if (fileName != "." && fileName != "..") {
      files.push_back(fileName);
    }
    free(list[i]);
  }
  free(list);
  std::sort(files.begin(), files.end());
  return files;

#elif defined(_WIN32)
#if (!defined(WINRT))

  std::vector<std::string> files;
  std::string fileMask = dirName;
  fileMask.append("\\*");
  WIN32_FIND_DATA FindFileData;
  HANDLE hFind = FindFirstFile(fileMask.c_str(), &FindFileData);
  // Directory is empty
  if (HandleToLong(&hFind) == ERROR_FILE_NOT_FOUND) {
    return files;
  }
  if (hFind == INVALID_HANDLE_VALUE) {
    throw(vpIoException(vpException::fatalError, "Cannot read files of directory %s", dirName.c_str()));
  }
  do {
    std::string fileName = FindFileData.cFileName;
    if (fileName != "." && fileName != "..") {
      files.push_back(fileName);
    }
  } while (FindNextFile(hFind, &FindFileData));
  FindClose(hFind);
  std::sort(files.begin(), files.end());
  return files;

#else
  throw(vpIoException(vpException::fatalError,
                      "Cannot read files of directory %s: not implemented on "
                      "Universal Windows Platform",
                      dirName.c_str()));
#endif
#endif
}

void vpIoTools::readBinaryValueLE(std::ifstream &file, int16_t &short_value)
{
  file.read((char *)(&short_value), sizeof(short_value));

#ifdef VISP_BIG_ENDIAN
  // Swap bytes order from little endian to big endian
  short_value = swap16bits((uint16_t)short_value);
#endif
}

void vpIoTools::readBinaryValueLE(std::ifstream &file, uint16_t &ushort_value)
{
  file.read((char *)(&ushort_value), sizeof(ushort_value));

#ifdef VISP_BIG_ENDIAN
  // Swap bytes order from little endian to big endian
  ushort_value = swap16bits(ushort_value);
#endif
}

void vpIoTools::readBinaryValueLE(std::ifstream &file, int32_t &int_value)
{
  file.read((char *)(&int_value), sizeof(int_value));

#ifdef VISP_BIG_ENDIAN
  // Swap bytes order from little endian to big endian
  int_value = swap32bits((uint32_t)int_value);
#endif
}

void vpIoTools::readBinaryValueLE(std::ifstream &file, uint32_t &uint_value)
{
  file.read((char *)(&uint_value), sizeof(uint_value));

#ifdef VISP_BIG_ENDIAN
  // Swap bytes order from little endian to big endian
  uint_value = swap32bits(uint_value);
#endif
}

void vpIoTools::readBinaryValueLE(std::ifstream &file, float &float_value)
{
  file.read((char *)(&float_value), sizeof(float_value));

#ifdef VISP_BIG_ENDIAN
  // Swap bytes order from little endian to big endian
  float_value = swapFloat(float_value);
#endif
}

void vpIoTools::readBinaryValueLE(std::ifstream &file, double &double_value)
{
  file.read((char *)(&double_value), sizeof(double_value));

#ifdef VISP_BIG_ENDIAN
  // Swap bytes order from little endian to big endian
  double_value = swapDouble(double_value);
#endif
}

void vpIoTools::writeBinaryValueLE(std::ofstream &file, const int16_t short_value)
{
#ifdef VISP_BIG_ENDIAN
  // Swap bytes order to little endian
  uint16_t swap_short = swap16bits((uint16_t)short_value);
  file.write((char *)(&swap_short), sizeof(swap_short));
#else
  file.write((char *)(&short_value), sizeof(short_value));
#endif
}

void vpIoTools::writeBinaryValueLE(std::ofstream &file, const uint16_t ushort_value)
{
#ifdef VISP_BIG_ENDIAN
  // Swap bytes order to little endian
  uint16_t swap_ushort = swap16bits(ushort_value);
  file.write((char *)(&swap_ushort), sizeof(swap_ushort));
#else
  file.write((char *)(&ushort_value), sizeof(ushort_value));
#endif
}

void vpIoTools::writeBinaryValueLE(std::ofstream &file, const int32_t int_value)
{
#ifdef VISP_BIG_ENDIAN
  // Swap bytes order to little endian
  uint32_t swap_int = swap32bits((uint32_t)int_value);
  file.write((char *)(&swap_int), sizeof(swap_int));
#else
  file.write((char *)(&int_value), sizeof(int_value));
#endif
}

void vpIoTools::writeBinaryValueLE(std::ofstream &file, const uint32_t uint_value)
{
#ifdef VISP_BIG_ENDIAN
  // Swap bytes order to little endian
  uint32_t swap_int = swap32bits(uint_value);
  file.write((char *)(&swap_int), sizeof(swap_int));
#else
  file.write((char *)(&uint_value), sizeof(uint_value));
#endif
}

void vpIoTools::writeBinaryValueLE(std::ofstream &file, const float float_value)
{
#ifdef VISP_BIG_ENDIAN
  // Swap bytes order to little endian
  float swap_float = swapFloat(float_value);
  file.write((char *)(&swap_float), sizeof(swap_float));
#else
  file.write((char *)(&float_value), sizeof(float_value));
#endif
}

void vpIoTools::writeBinaryValueLE(std::ofstream &file, const double double_value)
{
#ifdef VISP_BIG_ENDIAN
  // Swap bytes order to little endian
  double swap_double = swapDouble(double_value);
  file.write((char *)(&swap_double), sizeof(swap_double));
#else
  file.write((char *)(&double_value), sizeof(double_value));
#endif
}