Function decodeUtf8Ignore

packages/kaos/src/internal.ts:7–82

(data: Buffer)

}

function decodeUtf8Ignore(data: Buffer): string {
  let output = '';
  let i = 0;

  while (i < data.length) {
    const b0 = data[i];
    if (b0 === undefined) break;

    if (b0 <= 0x7f) {
      output += String.fromCodePoint(b0);
      i += 1;
      continue;
    }

    if (b0 >= 0xc2 && b0 <= 0xdf) {
      const b1 = data[i + 1];
      if (b1 !== undefined && isUtf8Continuation(b1)) {
        output += String.fromCodePoint(((b0 & 0x1f) << 6) | (b1 & 0x3f));
        i += 2;
        continue;
      }
      i += 1;
      continue;
    }

    if (b0 >= 0xe0 && b0 <= 0xef) {
      const b1 = data[i + 1];
      const b2 = data[i + 2];
      const validSecond =
        b1 !== undefined &&
        ((b0 === 0xe0 && b1 >= 0xa0 && b1 <= 0xbf) ||
          (b0 >= 0xe1 && b0 <= 0xec && isUtf8Continuation(b1)) ||
          (b0 === 0xed && b1 >= 0x80 && b1 <= 0x9f) ||
          (b0 >= 0xee && b0 <= 0xef && isUtf8Continuation(b1)));

      if (validSecond && b2 !== undefined && isUtf8Continuation(b2)) {
        output += String.fromCodePoint(((b0 & 0x0f) << 12) | ((b1 & 0x3f) << 6) | (b2 & 0x3f));
        i += 3;
        continue;
      }
      i += 1;
      continue;
    }

    if (b0 >= 0xf0 && b0 <= 0xf4) {
      const b1 = data[i + 1];
      const b2 = data[i + 2];
      const b3 = data[i + 3];
      const validSecond =
        b1 !== undefined &&
        ((b0 === 0xf0 && b1 >= 0x90 && b1 <= 0xbf) ||
          (b0 >= 0xf1 && b0 <= 0xf3 && isUtf8Continuation(b1)) ||
          (b0 === 0xf4 && b1 >= 0x80 && b1 <= 0x8f));

      if (
        validSecond &&
        b2 !== undefined &&
        b3 !== undefined &&