Method encodeString

Source/cmBase32.cxx:39–93

cmBase32Encoder::cmBase32Encoder() = default;

std::string cmBase32Encoder::encodeString(unsigned char const* input,
                                          size_t len, bool padding)
{
  std::string res;

  static size_t const blockSize = 5;
  static size_t const bufferSize = 8;
  char buffer[bufferSize];

  unsigned char const* end = input + len;
  while ((input + blockSize) <= end) {
    Base32Encode5(input, buffer);
    res.append(buffer, bufferSize);
    input += blockSize;
  }

  size_t remain = static_cast<size_t>(end - input);
  if (remain != 0) {
    // Temporary source buffer filled up with 0s
    unsigned char padded[blockSize];
    for (size_t ii = 0; ii != remain; ++ii) {
      padded[ii] = input[ii];
    }
    for (size_t ii = remain; ii != blockSize; ++ii) {
      padded[ii] = 0;
    }

    Base32Encode5(padded, buffer);
    size_t numPad(0);
    switch (remain) {
      case 1:
        numPad = 6;
        break;
      case 2:
        numPad = 4;
        break;
      case 3:
        numPad = 3;
        break;
      case 4:
        numPad = 1;
        break;
      default:
        break;
    }
    res.append(buffer, bufferSize - numPad);
    if (padding) {
      for (size_t ii = 0; ii != numPad; ++ii) {
        res.push_back(paddingChar);
      }
    }
  }

  return res;
}