getContentLength static method

BigInt getContentLength({ required Iterator<int> iterator, })

Implementation

static BigInt getContentLength({required Iterator<int> iterator}) {
  if (iterator.moveNext()) {
    int? first;
    try {
      first = iterator.current;
    } catch (e) {}
    if (first != null) {
      if ((first & 0x80) != 0) {
        // long

        var octetsToRead = first - 0x80;
        var data = <int>[];
        for (var i = 0; i < octetsToRead; i++) {
          if (iterator.moveNext()) {
            int? n;
            try {
              n = iterator.current;
            } catch (e) {}
            if (n != null) {
              data.add(n);
            }
          }
        }

        return toIntValue(data) ?? BigInt.from(0);
      } else {
        // short
        return BigInt.from(first);
      }
    }
  }
  return BigInt.from(0);
}