function inflate()

in TestApplications/JDIChromePlugin/DevPanel/libs/jszip/jszip.js [6441:7531]


function inflate(strm, flush) {
  var state;
  var input, output;          // input/output buffers
  var next;                   /* next input INDEX */
  var put;                    /* next output INDEX */
  var have, left;             /* available input and output */
  var hold;                   /* bit buffer */
  var bits;                   /* bits in bit buffer */
  var _in, _out;              /* save starting available input and output */
  var copy;                   /* number of stored or match bytes to copy */
  var from;                   /* where to copy match bytes from */
  var from_source;
  var here = 0;               /* current decoding table entry */
  var here_bits, here_op, here_val; // paked "here" denormalized (JS specific)
  //var last;                   /* parent table entry */
  var last_bits, last_op, last_val; // paked "last" denormalized (JS specific)
  var len;                    /* length to copy for repeats, bits to drop */
  var ret;                    /* return code */
  var hbuf = new utils.Buf8(4);    /* buffer for gzip header crc calculation */
  var opts;

  var n; // temporary var for NEED_BITS

  var order = /* permutation of code lengths */
    [16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15];


  if (!strm || !strm.state || !strm.output ||
      (!strm.input && strm.avail_in !== 0)) {
    return Z_STREAM_ERROR;
  }

  state = strm.state;
  if (state.mode === TYPE) { state.mode = TYPEDO; }    /* skip check */


  //--- LOAD() ---
  put = strm.next_out;
  output = strm.output;
  left = strm.avail_out;
  next = strm.next_in;
  input = strm.input;
  have = strm.avail_in;
  hold = state.hold;
  bits = state.bits;
  //---

  _in = have;
  _out = left;
  ret = Z_OK;

  inf_leave: // goto emulation
  for (;;) {
    switch (state.mode) {
    case HEAD:
      if (state.wrap === 0) {
        state.mode = TYPEDO;
        break;
      }
      //=== NEEDBITS(16);
      while (bits < 16) {
        if (have === 0) { break inf_leave; }
        have--;
        hold += input[next++] << bits;
        bits += 8;
      }
      //===//
      if ((state.wrap & 2) && hold === 0x8b1f) {  /* gzip header */
        state.check = 0/*crc32(0L, Z_NULL, 0)*/;
        //=== CRC2(state.check, hold);
        hbuf[0] = hold & 0xff;
        hbuf[1] = (hold >>> 8) & 0xff;
        state.check = crc32(state.check, hbuf, 2, 0);
        //===//

        //=== INITBITS();
        hold = 0;
        bits = 0;
        //===//
        state.mode = FLAGS;
        break;
      }
      state.flags = 0;           /* expect zlib header */
      if (state.head) {
        state.head.done = false;
      }
      if (!(state.wrap & 1) ||   /* check if zlib header allowed */
        (((hold & 0xff)/*BITS(8)*/ << 8) + (hold >> 8)) % 31) {
        strm.msg = 'incorrect header check';
        state.mode = BAD;
        break;
      }
      if ((hold & 0x0f)/*BITS(4)*/ !== Z_DEFLATED) {
        strm.msg = 'unknown compression method';
        state.mode = BAD;
        break;
      }
      //--- DROPBITS(4) ---//
      hold >>>= 4;
      bits -= 4;
      //---//
      len = (hold & 0x0f)/*BITS(4)*/ + 8;
      if (state.wbits === 0) {
        state.wbits = len;
      }
      else if (len > state.wbits) {
        strm.msg = 'invalid window size';
        state.mode = BAD;
        break;
      }
      state.dmax = 1 << len;
      //Tracev((stderr, "inflate:   zlib header ok\n"));
      strm.adler = state.check = 1/*adler32(0L, Z_NULL, 0)*/;
      state.mode = hold & 0x200 ? DICTID : TYPE;
      //=== INITBITS();
      hold = 0;
      bits = 0;
      //===//
      break;
    case FLAGS:
      //=== NEEDBITS(16); */
      while (bits < 16) {
        if (have === 0) { break inf_leave; }
        have--;
        hold += input[next++] << bits;
        bits += 8;
      }
      //===//
      state.flags = hold;
      if ((state.flags & 0xff) !== Z_DEFLATED) {
        strm.msg = 'unknown compression method';
        state.mode = BAD;
        break;
      }
      if (state.flags & 0xe000) {
        strm.msg = 'unknown header flags set';
        state.mode = BAD;
        break;
      }
      if (state.head) {
        state.head.text = ((hold >> 8) & 1);
      }
      if (state.flags & 0x0200) {
        //=== CRC2(state.check, hold);
        hbuf[0] = hold & 0xff;
        hbuf[1] = (hold >>> 8) & 0xff;
        state.check = crc32(state.check, hbuf, 2, 0);
        //===//
      }
      //=== INITBITS();
      hold = 0;
      bits = 0;
      //===//
      state.mode = TIME;
      /* falls through */
    case TIME:
      //=== NEEDBITS(32); */
      while (bits < 32) {
        if (have === 0) { break inf_leave; }
        have--;
        hold += input[next++] << bits;
        bits += 8;
      }
      //===//
      if (state.head) {
        state.head.time = hold;
      }
      if (state.flags & 0x0200) {
        //=== CRC4(state.check, hold)
        hbuf[0] = hold & 0xff;
        hbuf[1] = (hold >>> 8) & 0xff;
        hbuf[2] = (hold >>> 16) & 0xff;
        hbuf[3] = (hold >>> 24) & 0xff;
        state.check = crc32(state.check, hbuf, 4, 0);
        //===
      }
      //=== INITBITS();
      hold = 0;
      bits = 0;
      //===//
      state.mode = OS;
      /* falls through */
    case OS:
      //=== NEEDBITS(16); */
      while (bits < 16) {
        if (have === 0) { break inf_leave; }
        have--;
        hold += input[next++] << bits;
        bits += 8;
      }
      //===//
      if (state.head) {
        state.head.xflags = (hold & 0xff);
        state.head.os = (hold >> 8);
      }
      if (state.flags & 0x0200) {
        //=== CRC2(state.check, hold);
        hbuf[0] = hold & 0xff;
        hbuf[1] = (hold >>> 8) & 0xff;
        state.check = crc32(state.check, hbuf, 2, 0);
        //===//
      }
      //=== INITBITS();
      hold = 0;
      bits = 0;
      //===//
      state.mode = EXLEN;
      /* falls through */
    case EXLEN:
      if (state.flags & 0x0400) {
        //=== NEEDBITS(16); */
        while (bits < 16) {
          if (have === 0) { break inf_leave; }
          have--;
          hold += input[next++] << bits;
          bits += 8;
        }
        //===//
        state.length = hold;
        if (state.head) {
          state.head.extra_len = hold;
        }
        if (state.flags & 0x0200) {
          //=== CRC2(state.check, hold);
          hbuf[0] = hold & 0xff;
          hbuf[1] = (hold >>> 8) & 0xff;
          state.check = crc32(state.check, hbuf, 2, 0);
          //===//
        }
        //=== INITBITS();
        hold = 0;
        bits = 0;
        //===//
      }
      else if (state.head) {
        state.head.extra = null/*Z_NULL*/;
      }
      state.mode = EXTRA;
      /* falls through */
    case EXTRA:
      if (state.flags & 0x0400) {
        copy = state.length;
        if (copy > have) { copy = have; }
        if (copy) {
          if (state.head) {
            len = state.head.extra_len - state.length;
            if (!state.head.extra) {
              // Use untyped array for more conveniend processing later
              state.head.extra = new Array(state.head.extra_len);
            }
            utils.arraySet(
              state.head.extra,
              input,
              next,
              // extra field is limited to 65536 bytes
              // - no need for additional size check
              copy,
              /*len + copy > state.head.extra_max - len ? state.head.extra_max : copy,*/
              len
            );
            //zmemcpy(state.head.extra + len, next,
            //        len + copy > state.head.extra_max ?
            //        state.head.extra_max - len : copy);
          }
          if (state.flags & 0x0200) {
            state.check = crc32(state.check, input, copy, next);
          }
          have -= copy;
          next += copy;
          state.length -= copy;
        }
        if (state.length) { break inf_leave; }
      }
      state.length = 0;
      state.mode = NAME;
      /* falls through */
    case NAME:
      if (state.flags & 0x0800) {
        if (have === 0) { break inf_leave; }
        copy = 0;
        do {
          // TODO: 2 or 1 bytes?
          len = input[next + copy++];
          /* use constant limit because in js we should not preallocate memory */
          if (state.head && len &&
              (state.length < 65536 /*state.head.name_max*/)) {
            state.head.name += String.fromCharCode(len);
          }
        } while (len && copy < have);

        if (state.flags & 0x0200) {
          state.check = crc32(state.check, input, copy, next);
        }
        have -= copy;
        next += copy;
        if (len) { break inf_leave; }
      }
      else if (state.head) {
        state.head.name = null;
      }
      state.length = 0;
      state.mode = COMMENT;
      /* falls through */
    case COMMENT:
      if (state.flags & 0x1000) {
        if (have === 0) { break inf_leave; }
        copy = 0;
        do {
          len = input[next + copy++];
          /* use constant limit because in js we should not preallocate memory */
          if (state.head && len &&
              (state.length < 65536 /*state.head.comm_max*/)) {
            state.head.comment += String.fromCharCode(len);
          }
        } while (len && copy < have);
        if (state.flags & 0x0200) {
          state.check = crc32(state.check, input, copy, next);
        }
        have -= copy;
        next += copy;
        if (len) { break inf_leave; }
      }
      else if (state.head) {
        state.head.comment = null;
      }
      state.mode = HCRC;
      /* falls through */
    case HCRC:
      if (state.flags & 0x0200) {
        //=== NEEDBITS(16); */
        while (bits < 16) {
          if (have === 0) { break inf_leave; }
          have--;
          hold += input[next++] << bits;
          bits += 8;
        }
        //===//
        if (hold !== (state.check & 0xffff)) {
          strm.msg = 'header crc mismatch';
          state.mode = BAD;
          break;
        }
        //=== INITBITS();
        hold = 0;
        bits = 0;
        //===//
      }
      if (state.head) {
        state.head.hcrc = ((state.flags >> 9) & 1);
        state.head.done = true;
      }
      strm.adler = state.check = 0 /*crc32(0L, Z_NULL, 0)*/;
      state.mode = TYPE;
      break;
    case DICTID:
      //=== NEEDBITS(32); */
      while (bits < 32) {
        if (have === 0) { break inf_leave; }
        have--;
        hold += input[next++] << bits;
        bits += 8;
      }
      //===//
      strm.adler = state.check = ZSWAP32(hold);
      //=== INITBITS();
      hold = 0;
      bits = 0;
      //===//
      state.mode = DICT;
      /* falls through */
    case DICT:
      if (state.havedict === 0) {
        //--- RESTORE() ---
        strm.next_out = put;
        strm.avail_out = left;
        strm.next_in = next;
        strm.avail_in = have;
        state.hold = hold;
        state.bits = bits;
        //---
        return Z_NEED_DICT;
      }
      strm.adler = state.check = 1/*adler32(0L, Z_NULL, 0)*/;
      state.mode = TYPE;
      /* falls through */
    case TYPE:
      if (flush === Z_BLOCK || flush === Z_TREES) { break inf_leave; }
      /* falls through */
    case TYPEDO:
      if (state.last) {
        //--- BYTEBITS() ---//
        hold >>>= bits & 7;
        bits -= bits & 7;
        //---//
        state.mode = CHECK;
        break;
      }
      //=== NEEDBITS(3); */
      while (bits < 3) {
        if (have === 0) { break inf_leave; }
        have--;
        hold += input[next++] << bits;
        bits += 8;
      }
      //===//
      state.last = (hold & 0x01)/*BITS(1)*/;
      //--- DROPBITS(1) ---//
      hold >>>= 1;
      bits -= 1;
      //---//

      switch ((hold & 0x03)/*BITS(2)*/) {
      case 0:                             /* stored block */
        //Tracev((stderr, "inflate:     stored block%s\n",
        //        state.last ? " (last)" : ""));
        state.mode = STORED;
        break;
      case 1:                             /* fixed block */
        fixedtables(state);
        //Tracev((stderr, "inflate:     fixed codes block%s\n",
        //        state.last ? " (last)" : ""));
        state.mode = LEN_;             /* decode codes */
        if (flush === Z_TREES) {
          //--- DROPBITS(2) ---//
          hold >>>= 2;
          bits -= 2;
          //---//
          break inf_leave;
        }
        break;
      case 2:                             /* dynamic block */
        //Tracev((stderr, "inflate:     dynamic codes block%s\n",
        //        state.last ? " (last)" : ""));
        state.mode = TABLE;
        break;
      case 3:
        strm.msg = 'invalid block type';
        state.mode = BAD;
      }
      //--- DROPBITS(2) ---//
      hold >>>= 2;
      bits -= 2;
      //---//
      break;
    case STORED:
      //--- BYTEBITS() ---// /* go to byte boundary */
      hold >>>= bits & 7;
      bits -= bits & 7;
      //---//
      //=== NEEDBITS(32); */
      while (bits < 32) {
        if (have === 0) { break inf_leave; }
        have--;
        hold += input[next++] << bits;
        bits += 8;
      }
      //===//
      if ((hold & 0xffff) !== ((hold >>> 16) ^ 0xffff)) {
        strm.msg = 'invalid stored block lengths';
        state.mode = BAD;
        break;
      }
      state.length = hold & 0xffff;
      //Tracev((stderr, "inflate:       stored length %u\n",
      //        state.length));
      //=== INITBITS();
      hold = 0;
      bits = 0;
      //===//
      state.mode = COPY_;
      if (flush === Z_TREES) { break inf_leave; }
      /* falls through */
    case COPY_:
      state.mode = COPY;
      /* falls through */
    case COPY:
      copy = state.length;
      if (copy) {
        if (copy > have) { copy = have; }
        if (copy > left) { copy = left; }
        if (copy === 0) { break inf_leave; }
        //--- zmemcpy(put, next, copy); ---
        utils.arraySet(output, input, next, copy, put);
        //---//
        have -= copy;
        next += copy;
        left -= copy;
        put += copy;
        state.length -= copy;
        break;
      }
      //Tracev((stderr, "inflate:       stored end\n"));
      state.mode = TYPE;
      break;
    case TABLE:
      //=== NEEDBITS(14); */
      while (bits < 14) {
        if (have === 0) { break inf_leave; }
        have--;
        hold += input[next++] << bits;
        bits += 8;
      }
      //===//
      state.nlen = (hold & 0x1f)/*BITS(5)*/ + 257;
      //--- DROPBITS(5) ---//
      hold >>>= 5;
      bits -= 5;
      //---//
      state.ndist = (hold & 0x1f)/*BITS(5)*/ + 1;
      //--- DROPBITS(5) ---//
      hold >>>= 5;
      bits -= 5;
      //---//
      state.ncode = (hold & 0x0f)/*BITS(4)*/ + 4;
      //--- DROPBITS(4) ---//
      hold >>>= 4;
      bits -= 4;
      //---//
//#ifndef PKZIP_BUG_WORKAROUND
      if (state.nlen > 286 || state.ndist > 30) {
        strm.msg = 'too many length or distance symbols';
        state.mode = BAD;
        break;
      }
//#endif
      //Tracev((stderr, "inflate:       table sizes ok\n"));
      state.have = 0;
      state.mode = LENLENS;
      /* falls through */
    case LENLENS:
      while (state.have < state.ncode) {
        //=== NEEDBITS(3);
        while (bits < 3) {
          if (have === 0) { break inf_leave; }
          have--;
          hold += input[next++] << bits;
          bits += 8;
        }
        //===//
        state.lens[order[state.have++]] = (hold & 0x07);//BITS(3);
        //--- DROPBITS(3) ---//
        hold >>>= 3;
        bits -= 3;
        //---//
      }
      while (state.have < 19) {
        state.lens[order[state.have++]] = 0;
      }
      // We have separate tables & no pointers. 2 commented lines below not needed.
      //state.next = state.codes;
      //state.lencode = state.next;
      // Switch to use dynamic table
      state.lencode = state.lendyn;
      state.lenbits = 7;

      opts = {bits: state.lenbits};
      ret = inflate_table(CODES, state.lens, 0, 19, state.lencode, 0, state.work, opts);
      state.lenbits = opts.bits;

      if (ret) {
        strm.msg = 'invalid code lengths set';
        state.mode = BAD;
        break;
      }
      //Tracev((stderr, "inflate:       code lengths ok\n"));
      state.have = 0;
      state.mode = CODELENS;
      /* falls through */
    case CODELENS:
      while (state.have < state.nlen + state.ndist) {
        for (;;) {
          here = state.lencode[hold & ((1 << state.lenbits) - 1)];/*BITS(state.lenbits)*/
          here_bits = here >>> 24;
          here_op = (here >>> 16) & 0xff;
          here_val = here & 0xffff;

          if ((here_bits) <= bits) { break; }
          //--- PULLBYTE() ---//
          if (have === 0) { break inf_leave; }
          have--;
          hold += input[next++] << bits;
          bits += 8;
          //---//
        }
        if (here_val < 16) {
          //--- DROPBITS(here.bits) ---//
          hold >>>= here_bits;
          bits -= here_bits;
          //---//
          state.lens[state.have++] = here_val;
        }
        else {
          if (here_val === 16) {
            //=== NEEDBITS(here.bits + 2);
            n = here_bits + 2;
            while (bits < n) {
              if (have === 0) { break inf_leave; }
              have--;
              hold += input[next++] << bits;
              bits += 8;
            }
            //===//
            //--- DROPBITS(here.bits) ---//
            hold >>>= here_bits;
            bits -= here_bits;
            //---//
            if (state.have === 0) {
              strm.msg = 'invalid bit length repeat';
              state.mode = BAD;
              break;
            }
            len = state.lens[state.have - 1];
            copy = 3 + (hold & 0x03);//BITS(2);
            //--- DROPBITS(2) ---//
            hold >>>= 2;
            bits -= 2;
            //---//
          }
          else if (here_val === 17) {
            //=== NEEDBITS(here.bits + 3);
            n = here_bits + 3;
            while (bits < n) {
              if (have === 0) { break inf_leave; }
              have--;
              hold += input[next++] << bits;
              bits += 8;
            }
            //===//
            //--- DROPBITS(here.bits) ---//
            hold >>>= here_bits;
            bits -= here_bits;
            //---//
            len = 0;
            copy = 3 + (hold & 0x07);//BITS(3);
            //--- DROPBITS(3) ---//
            hold >>>= 3;
            bits -= 3;
            //---//
          }
          else {
            //=== NEEDBITS(here.bits + 7);
            n = here_bits + 7;
            while (bits < n) {
              if (have === 0) { break inf_leave; }
              have--;
              hold += input[next++] << bits;
              bits += 8;
            }
            //===//
            //--- DROPBITS(here.bits) ---//
            hold >>>= here_bits;
            bits -= here_bits;
            //---//
            len = 0;
            copy = 11 + (hold & 0x7f);//BITS(7);
            //--- DROPBITS(7) ---//
            hold >>>= 7;
            bits -= 7;
            //---//
          }
          if (state.have + copy > state.nlen + state.ndist) {
            strm.msg = 'invalid bit length repeat';
            state.mode = BAD;
            break;
          }
          while (copy--) {
            state.lens[state.have++] = len;
          }
        }
      }

      /* handle error breaks in while */
      if (state.mode === BAD) { break; }

      /* check for end-of-block code (better have one) */
      if (state.lens[256] === 0) {
        strm.msg = 'invalid code -- missing end-of-block';
        state.mode = BAD;
        break;
      }

      /* build code tables -- note: do not change the lenbits or distbits
         values here (9 and 6) without reading the comments in inftrees.h
         concerning the ENOUGH constants, which depend on those values */
      state.lenbits = 9;

      opts = {bits: state.lenbits};
      ret = inflate_table(LENS, state.lens, 0, state.nlen, state.lencode, 0, state.work, opts);
      // We have separate tables & no pointers. 2 commented lines below not needed.
      // state.next_index = opts.table_index;
      state.lenbits = opts.bits;
      // state.lencode = state.next;

      if (ret) {
        strm.msg = 'invalid literal/lengths set';
        state.mode = BAD;
        break;
      }

      state.distbits = 6;
      //state.distcode.copy(state.codes);
      // Switch to use dynamic table
      state.distcode = state.distdyn;
      opts = {bits: state.distbits};
      ret = inflate_table(DISTS, state.lens, state.nlen, state.ndist, state.distcode, 0, state.work, opts);
      // We have separate tables & no pointers. 2 commented lines below not needed.
      // state.next_index = opts.table_index;
      state.distbits = opts.bits;
      // state.distcode = state.next;

      if (ret) {
        strm.msg = 'invalid distances set';
        state.mode = BAD;
        break;
      }
      //Tracev((stderr, 'inflate:       codes ok\n'));
      state.mode = LEN_;
      if (flush === Z_TREES) { break inf_leave; }
      /* falls through */
    case LEN_:
      state.mode = LEN;
      /* falls through */
    case LEN:
      if (have >= 6 && left >= 258) {
        //--- RESTORE() ---
        strm.next_out = put;
        strm.avail_out = left;
        strm.next_in = next;
        strm.avail_in = have;
        state.hold = hold;
        state.bits = bits;
        //---
        inflate_fast(strm, _out);
        //--- LOAD() ---
        put = strm.next_out;
        output = strm.output;
        left = strm.avail_out;
        next = strm.next_in;
        input = strm.input;
        have = strm.avail_in;
        hold = state.hold;
        bits = state.bits;
        //---

        if (state.mode === TYPE) {
          state.back = -1;
        }
        break;
      }
      state.back = 0;
      for (;;) {
        here = state.lencode[hold & ((1 << state.lenbits) -1)];  /*BITS(state.lenbits)*/
        here_bits = here >>> 24;
        here_op = (here >>> 16) & 0xff;
        here_val = here & 0xffff;

        if (here_bits <= bits) { break; }
        //--- PULLBYTE() ---//
        if (have === 0) { break inf_leave; }
        have--;
        hold += input[next++] << bits;
        bits += 8;
        //---//
      }
      if (here_op && (here_op & 0xf0) === 0) {
        last_bits = here_bits;
        last_op = here_op;
        last_val = here_val;
        for (;;) {
          here = state.lencode[last_val +
                  ((hold & ((1 << (last_bits + last_op)) -1))/*BITS(last.bits + last.op)*/ >> last_bits)];
          here_bits = here >>> 24;
          here_op = (here >>> 16) & 0xff;
          here_val = here & 0xffff;

          if ((last_bits + here_bits) <= bits) { break; }
          //--- PULLBYTE() ---//
          if (have === 0) { break inf_leave; }
          have--;
          hold += input[next++] << bits;
          bits += 8;
          //---//
        }
        //--- DROPBITS(last.bits) ---//
        hold >>>= last_bits;
        bits -= last_bits;
        //---//
        state.back += last_bits;
      }
      //--- DROPBITS(here.bits) ---//
      hold >>>= here_bits;
      bits -= here_bits;
      //---//
      state.back += here_bits;
      state.length = here_val;
      if (here_op === 0) {
        //Tracevv((stderr, here.val >= 0x20 && here.val < 0x7f ?
        //        "inflate:         literal '%c'\n" :
        //        "inflate:         literal 0x%02x\n", here.val));
        state.mode = LIT;
        break;
      }
      if (here_op & 32) {
        //Tracevv((stderr, "inflate:         end of block\n"));
        state.back = -1;
        state.mode = TYPE;
        break;
      }
      if (here_op & 64) {
        strm.msg = 'invalid literal/length code';
        state.mode = BAD;
        break;
      }
      state.extra = here_op & 15;
      state.mode = LENEXT;
      /* falls through */
    case LENEXT:
      if (state.extra) {
        //=== NEEDBITS(state.extra);
        n = state.extra;
        while (bits < n) {
          if (have === 0) { break inf_leave; }
          have--;
          hold += input[next++] << bits;
          bits += 8;
        }
        //===//
        state.length += hold & ((1 << state.extra) -1)/*BITS(state.extra)*/;
        //--- DROPBITS(state.extra) ---//
        hold >>>= state.extra;
        bits -= state.extra;
        //---//
        state.back += state.extra;
      }
      //Tracevv((stderr, "inflate:         length %u\n", state.length));
      state.was = state.length;
      state.mode = DIST;
      /* falls through */
    case DIST:
      for (;;) {
        here = state.distcode[hold & ((1 << state.distbits) -1)];/*BITS(state.distbits)*/
        here_bits = here >>> 24;
        here_op = (here >>> 16) & 0xff;
        here_val = here & 0xffff;

        if ((here_bits) <= bits) { break; }
        //--- PULLBYTE() ---//
        if (have === 0) { break inf_leave; }
        have--;
        hold += input[next++] << bits;
        bits += 8;
        //---//
      }
      if ((here_op & 0xf0) === 0) {
        last_bits = here_bits;
        last_op = here_op;
        last_val = here_val;
        for (;;) {
          here = state.distcode[last_val +
                  ((hold & ((1 << (last_bits + last_op)) -1))/*BITS(last.bits + last.op)*/ >> last_bits)];
          here_bits = here >>> 24;
          here_op = (here >>> 16) & 0xff;
          here_val = here & 0xffff;

          if ((last_bits + here_bits) <= bits) { break; }
          //--- PULLBYTE() ---//
          if (have === 0) { break inf_leave; }
          have--;
          hold += input[next++] << bits;
          bits += 8;
          //---//
        }
        //--- DROPBITS(last.bits) ---//
        hold >>>= last_bits;
        bits -= last_bits;
        //---//
        state.back += last_bits;
      }
      //--- DROPBITS(here.bits) ---//
      hold >>>= here_bits;
      bits -= here_bits;
      //---//
      state.back += here_bits;
      if (here_op & 64) {
        strm.msg = 'invalid distance code';
        state.mode = BAD;
        break;
      }
      state.offset = here_val;
      state.extra = (here_op) & 15;
      state.mode = DISTEXT;
      /* falls through */
    case DISTEXT:
      if (state.extra) {
        //=== NEEDBITS(state.extra);
        n = state.extra;
        while (bits < n) {
          if (have === 0) { break inf_leave; }
          have--;
          hold += input[next++] << bits;
          bits += 8;
        }
        //===//
        state.offset += hold & ((1 << state.extra) -1)/*BITS(state.extra)*/;
        //--- DROPBITS(state.extra) ---//
        hold >>>= state.extra;
        bits -= state.extra;
        //---//
        state.back += state.extra;
      }
//#ifdef INFLATE_STRICT
      if (state.offset > state.dmax) {
        strm.msg = 'invalid distance too far back';
        state.mode = BAD;
        break;
      }
//#endif
      //Tracevv((stderr, "inflate:         distance %u\n", state.offset));
      state.mode = MATCH;
      /* falls through */
    case MATCH:
      if (left === 0) { break inf_leave; }
      copy = _out - left;
      if (state.offset > copy) {         /* copy from window */
        copy = state.offset - copy;
        if (copy > state.whave) {
          if (state.sane) {
            strm.msg = 'invalid distance too far back';
            state.mode = BAD;
            break;
          }
// (!) This block is disabled in zlib defailts,
// don't enable it for binary compatibility
//#ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR
//          Trace((stderr, "inflate.c too far\n"));
//          copy -= state.whave;
//          if (copy > state.length) { copy = state.length; }
//          if (copy > left) { copy = left; }
//          left -= copy;
//          state.length -= copy;
//          do {
//            output[put++] = 0;
//          } while (--copy);
//          if (state.length === 0) { state.mode = LEN; }
//          break;
//#endif
        }
        if (copy > state.wnext) {
          copy -= state.wnext;
          from = state.wsize - copy;
        }
        else {
          from = state.wnext - copy;
        }
        if (copy > state.length) { copy = state.length; }
        from_source = state.window;
      }
      else {                              /* copy from output */
        from_source = output;
        from = put - state.offset;
        copy = state.length;
      }
      if (copy > left) { copy = left; }
      left -= copy;
      state.length -= copy;
      do {
        output[put++] = from_source[from++];
      } while (--copy);
      if (state.length === 0) { state.mode = LEN; }
      break;
    case LIT:
      if (left === 0) { break inf_leave; }
      output[put++] = state.length;
      left--;
      state.mode = LEN;
      break;
    case CHECK:
      if (state.wrap) {
        //=== NEEDBITS(32);
        while (bits < 32) {
          if (have === 0) { break inf_leave; }
          have--;
          // Use '|' insdead of '+' to make sure that result is signed
          hold |= input[next++] << bits;
          bits += 8;
        }
        //===//
        _out -= left;
        strm.total_out += _out;
        state.total += _out;
        if (_out) {
          strm.adler = state.check =
              /*UPDATE(state.check, put - _out, _out);*/
              (state.flags ? crc32(state.check, output, _out, put - _out) : adler32(state.check, output, _out, put - _out));

        }
        _out = left;
        // NB: crc32 stored as signed 32-bit int, ZSWAP32 returns signed too
        if ((state.flags ? hold : ZSWAP32(hold)) !== state.check) {
          strm.msg = 'incorrect data check';
          state.mode = BAD;
          break;
        }
        //=== INITBITS();
        hold = 0;
        bits = 0;
        //===//
        //Tracev((stderr, "inflate:   check matches trailer\n"));
      }
      state.mode = LENGTH;
      /* falls through */
    case LENGTH:
      if (state.wrap && state.flags) {
        //=== NEEDBITS(32);
        while (bits < 32) {
          if (have === 0) { break inf_leave; }
          have--;
          hold += input[next++] << bits;
          bits += 8;
        }
        //===//
        if (hold !== (state.total & 0xffffffff)) {
          strm.msg = 'incorrect length check';
          state.mode = BAD;
          break;
        }
        //=== INITBITS();
        hold = 0;
        bits = 0;
        //===//
        //Tracev((stderr, "inflate:   length matches trailer\n"));
      }
      state.mode = DONE;
      /* falls through */
    case DONE:
      ret = Z_STREAM_END;
      break inf_leave;
    case BAD:
      ret = Z_DATA_ERROR;
      break inf_leave;
    case MEM:
      return Z_MEM_ERROR;
    case SYNC:
      /* falls through */
    default:
      return Z_STREAM_ERROR;
    }
  }

  // inf_leave <- here is real place for "goto inf_leave", emulated via "break inf_leave"

  /*
     Return from inflate(), updating the total counts and the check value.
     If there was no progress during the inflate() call, return a buffer
     error.  Call updatewindow() to create and/or update the window state.
     Note: a memory error from inflate() is non-recoverable.
   */

  //--- RESTORE() ---
  strm.next_out = put;
  strm.avail_out = left;
  strm.next_in = next;
  strm.avail_in = have;
  state.hold = hold;
  state.bits = bits;
  //---

  if (state.wsize || (_out !== strm.avail_out && state.mode < BAD &&
                      (state.mode < CHECK || flush !== Z_FINISH))) {
    if (updatewindow(strm, strm.output, strm.next_out, _out - strm.avail_out)) {
      state.mode = MEM;
      return Z_MEM_ERROR;
    }
  }
  _in -= strm.avail_in;
  _out -= strm.avail_out;
  strm.total_in += _in;
  strm.total_out += _out;
  state.total += _out;
  if (state.wrap && _out) {
    strm.adler = state.check = /*UPDATE(state.check, strm.next_out - _out, _out);*/
      (state.flags ? crc32(state.check, output, _out, strm.next_out - _out) : adler32(state.check, output, _out, strm.next_out - _out));
  }
  strm.data_type = state.bits + (state.last ? 64 : 0) +
                    (state.mode === TYPE ? 128 : 0) +
                    (state.mode === LEN_ || state.mode === COPY_ ? 256 : 0);
  if (((_in === 0 && _out === 0) || flush === Z_FINISH) && ret === Z_OK) {
    ret = Z_BUF_ERROR;
  }
  return ret;
}