Function ReadEncodedBlock

IO/Legacy/vtkLegacyStatisticalModelReader.cxx:28–70

template <typename LineType>
bool ReadEncodedBlock(const char* blockName, std::string& decodedData,
  vtkLegacyStatisticalModelReader* self, LineType& line)
{
  if (!self->ReadString(line) || strncmp(self->LowerCase(line), blockName, strlen(blockName)) != 0)
  {
    vtkErrorWithObjectMacro(self, << "Cannot read " << blockName << " \"" << line << "\"!");
    return false;
  }

  vtkIdType encodedContentLength;
  vtkIdType decodedContentLength;
  if (!self->Read(&encodedContentLength) || !self->Read(&decodedContentLength))
  {
    vtkErrorWithObjectMacro(self, << "Cannot read content length: " << line);
    return false;
  }

  // Now read encoded data, beginning with a newline.
  if (!self->ReadLine(line))
  {
    vtkErrorWithObjectMacro(self, << "Cannot read end-of-line past content length: " << line);
    return false;
  }

  if (encodedContentLength > 0)
  {
    // Use 'char' instead of 'uint8_t' to avoid the following clang >= 19 error:
    // "implicit instantiation of undefined template 'std::char_traits<unsigned char>'"
    std::vector<char> raw;
    raw.resize(encodedContentLength);
    if (!self->GetIStream()->read(raw.data(), static_cast<std::streamsize>(encodedContentLength)))
    {
      vtkErrorWithObjectMacro(self, << "Cannot read encoded " << blockName << " content.");
      return false;
    }
    decodedData.resize(decodedContentLength, '\0');
    auto decodedLength = static_cast<vtkIdType>(vtkBase64Utilities::DecodeSafely(
      reinterpret_cast<const unsigned char*>(raw.data()), encodedContentLength,
      reinterpret_cast<unsigned char*>(decodedData.data()), decodedData.size()));
    decodedData.resize(decodedLength < decodedContentLength ? decodedLength : decodedContentLength);
  }
  return true;
}

} // anonymous namespace