Function simplicity_decodeUptoMaxInt

src/simplicity/bitstream.c:187–202

Decode an encoded number between 1 and 2^31 - 1 inclusive. * When successful returns the decoded result. * If the decoded value would be too large, 'SIMPLICITY_ERR_DATA_OUT_OF_RANGE' is returned. * If more bits are needed than available in the 'stream', 'SIMPLICITY_ERR_BITSTRING_EOF' is returned. * If an I/O error occurs when reading from the 'stream', 'SIMPLICITY_ERR_BISTRING_ERROR' is return

 * Precondition: NULL != stream
 */
int32_t simplicity_decodeUptoMaxInt(bitstream* stream) {
  int32_t bit = read1Bit(stream);
  if (bit < 0) return bit;
  if (0 == bit) {
    return 1;
  } else {
    int32_t n = decodeUpto65535(stream);
    if (n < 0) return n;
    if (30 < n) return SIMPLICITY_ERR_DATA_OUT_OF_RANGE;
    {
      int32_t result = simplicity_readNBits(n, stream);
      if (result < 0) return result;
      return ((1 << n) | result);
    }
  }
}

/* Fills a 'bitstring' containing 'n' bits from 'stream'.
 * Returns 'SIMPLICITY_ERR_BITSTREAM_EOF' if not enough bits are available.