Function inflateRaw

packages/plugins/apps/src/git-client/packfile.ts:186–265

(
  buf: Uint8Array,
  pos: number,
  limits: Pick<ParsePackLimits, "maxObjectBytes"> = DEFAULT_LIMITS,
)

}

function inflateRaw(
  buf: Uint8Array,
  pos: number,
  limits: Pick<ParsePackLimits, "maxObjectBytes"> = DEFAULT_LIMITS,
): { out: Uint8Array; endPos: number } {
  const br = new BitReader(buf, pos);
  const out: number[] = [];
  let final = 0;
  do {
    final = br.bit();
    const type = br.bits(2);
    if (type === 0) {
      br.align();
      requireAvailable(buf, br.pos, 4, "stored deflate block header");
      const len = buf[br.pos] | (buf[br.pos + 1] << 8);
      const nlen = buf[br.pos + 2] | (buf[br.pos + 3] << 8);
      if (((len ^ 0xffff) & 0xffff) !== nlen) {
        throw new PackParseError("bad stored deflate length");
      }
      br.pos += 4; // len + nlen
      requireAvailable(buf, br.pos, len, "stored deflate block");
      for (let i = 0; i < len; i++) pushInflated(out, buf[br.pos++]!, limits.maxObjectBytes);
    } else {
      let litH: Huff, distH: Huff;
      if (type === 1) {
        const ll = new Array(288);
        for (let i = 0; i < 144; i++) ll[i] = 8;
        for (let i = 144; i < 256; i++) ll[i] = 9;
        for (let i = 256; i < 280; i++) ll[i] = 7;
        for (let i = 280; i < 288; i++) ll[i] = 8;
        litH = buildHuff(ll, 288);
        distH = buildHuff(new Array(30).fill(5), 30);
      } else {
        const hlit = br.bits(5) + 257;
        const hdist = br.bits(5) + 1;
        const hclen = br.bits(4) + 4;
        const clen = new Array(19).fill(0);
        for (let i = 0; i < hclen; i++) clen[CLEN_ORDER[i]] = br.bits(3);
        const clH = buildHuff(clen, 19);
        const lengths: number[] = [];
        while (lengths.length < hlit + hdist) {
          const sym = decodeSym(br, clH);
          if (sym < 16) lengths.push(sym);
          else if (sym === 16) {
            const r = br.bits(2) + 3;
            const prev = lengths[lengths.length - 1];
            for (let i = 0; i < r; i++) lengths.push(prev);
          } else if (sym === 17) {
            const r = br.bits(3) + 3;
            for (let i = 0; i < r; i++) lengths.push(0);
          } else {
            const r = br.bits(7) + 11;
            for (let i = 0; i < r; i++) lengths.push(0);
          }
        }
        litH = buildHuff(lengths.slice(0, hlit), hlit);
        distH = buildHuff(lengths.slice(hlit), hdist);
      }