AZ_NODISCARD az_span az_json_string_unescape()

in sdk/src/azure/core/az_json_token.c [328:378]

• 38 lines of code
• 7 McCabe index (conditional complexity)

AZ_NODISCARD az_span az_json_string_unescape(az_span json_string, az_span destination)
{
  _az_PRECONDITION_VALID_SPAN(json_string, 1, false);

  int32_t span_size = az_span_size(json_string);

  // The destination needs to be at least as large as the input, in the worst case.
  _az_PRECONDITION_VALID_SPAN(destination, span_size, false);

  int32_t position = 0;
  uint8_t* span_ptr = az_span_ptr(json_string);
  uint8_t* destination_ptr = az_span_ptr(destination);
  int32_t destination_size = az_span_size(destination);
  for (int32_t i = 0; i < span_size; i++)
  {
    uint8_t current_char = span_ptr[i];
    if (current_char == '\\' && i < span_size - 1)
    {
      uint8_t next_char = span_ptr[i + 1];
      // check that we have something to escape
      if (_az_is_valid_escaped_character(next_char))
      {
        current_char = _az_json_unescape_single_byte(next_char);
        i++;
      }
      else
      {
        // We assume that the input json is well-formed, but stop processing, in-case it isn't.
        return az_span_slice(destination, 0, position);
      }
    }
    else if (current_char == '\\')
    {
      // At this point, we are at the last character, i == span_size - 1
      // We assume that the input json is well-formed, but stop processing, in-case it isn't.
      return az_span_slice(destination, 0, position);
    }

    if (position > destination_size)
    {
      // We assume that the destination buffer is large enough, but stop processing, in-case it
      // isn't.
      return az_span_slice(destination, 0, position);
    }

    destination_ptr[position] = current_char;
    position++;
  }

  return az_span_slice(destination, 0, position);
}