Method ReadIntegerValue

IO/Geometry/vtkOpenFOAMReader.cxx:2701–2765

specialized for reading an integer value. not using the standard strtol() for speed reason.

// specialized for reading an integer value.
// not using the standard strtol() for speed reason.
vtkTypeInt64 vtkFoamFile::ReadIntegerValue()
{
  // skip prepending invalid chars
  // expanded the outermost loop in nextTokenHead() for performance
  int c;
  while (std::isspace(c = this->Getc())) // isspace() accepts -1 as EOF
  {
    if (c == '\n')
    {
      ++this->Superclass::LineNumber;
#if VTK_FOAMFILE_RECOGNIZE_LINEHEAD
      this->Superclass::WasNewline = true;
#endif
    }
  }

  // If a '/' is encountered, handle it as a comment/alternative token start.
  if (c == '/')
  {
    this->PutBack(c);
    c = this->NextTokenHead();
  }

  // leading sign?
  const bool negNum = (c == '-');
  if (negNum || c == '+')
  {
    c = this->Getc();
    if (c == '\n')
    {
      ++this->Superclass::LineNumber;
#if VTK_FOAMFILE_RECOGNIZE_LINEHEAD
      this->Superclass::WasNewline = true;
#endif
    }
  }

  if (!std::isdigit(c)) // isdigit() accepts -1 as EOF
  {
    if (c == EOF)
    {
      this->ThrowUnexpectedEOFException();
    }
    else
    {
      this->ThrowUnexpectedNondigitException(c);
    }
  }

  // Add the first digit.
  vtkTypeInt64 num = c - '0';
  // Continue collecting all the following digits.
  while (std::isdigit(c = this->Getc()))
  {
    num = 10 * num + c - '0';
  }

  if (c == EOF)