text: /* Copyright (C) 1999 Masanao Izumo <iz@onicos.co.jp>
   * Version: 1.0.1
   * LastModified: Dec 25 1999
   */
  
  /* Interface:
   * data = zip_deflate(src);
   */
  
  /* constant parameters */
  var zip_WSIZE = 32768;		// Sliding Window size
  var zip_STORED_BLOCK = 0;
  var zip_STATIC_TREES = 1;
  var zip_DYN_TREES    = 2;
  
  /* for deflate */
  var zip_DEFAULT_LEVEL = 6;
  var zip_FULL_SEARCH = true;
  var zip_INBUFSIZ = 32768;	// Input buffer size
  var zip_INBUF_EXTRA = 64;	// Extra buffer
  var zip_OUTBUFSIZ = 1024 * 8;
  var zip_window_size = 2 * zip_WSIZE;
  var zip_MIN_MATCH = 3;
  var zip_MAX_MATCH = 258;
  var zip_BITS = 16;
  // for SMALL_MEM
  var zip_LIT_BUFSIZE = 0x2000;
  var zip_HASH_BITS = 13;
  // for MEDIUM_MEM
  // var zip_LIT_BUFSIZE = 0x4000;
  // var zip_HASH_BITS = 14;
  // for BIG_MEM
  // var zip_LIT_BUFSIZE = 0x8000;
  // var zip_HASH_BITS = 15;
  if(zip_LIT_BUFSIZE > zip_INBUFSIZ)
      alert("error: zip_INBUFSIZ is too small");
  if((zip_WSIZE<<1) > (1<<zip_BITS))
      alert("error: zip_WSIZE is too large");
  if(zip_HASH_BITS > zip_BITS-1)
      alert("error: zip_HASH_BITS is too large");
  if(zip_HASH_BITS < 8 || zip_MAX_MATCH != 258)
      alert("error: Code too clever");
  var zip_DIST_BUFSIZE = zip_LIT_BUFSIZE;
  var zip_HASH_SIZE = 1 << zip_HASH_BITS;
  var zip_HASH_MASK = zip_HASH_SIZE - 1;
  var zip_WMASK = zip_WSIZE - 1;
  var zip_NIL = 0; // Tail of hash chains
  var zip_TOO_FAR = 4096;
  var zip_MIN_LOOKAHEAD = zip_MAX_MATCH + zip_MIN_MATCH + 1;
  var zip_MAX_DIST = zip_WSIZE - zip_MIN_LOOKAHEAD;
  var zip_SMALLEST = 1;
  var zip_MAX_BITS = 15;
  var zip_MAX_BL_BITS = 7;
  var zip_LENGTH_CODES = 29;
  var zip_LITERALS =256;
  var zip_END_BLOCK = 256;
  var zip_L_CODES = zip_LITERALS + 1 + zip_LENGTH_CODES;
  var zip_D_CODES = 30;
  var zip_BL_CODES = 19;
  var zip_REP_3_6 = 16;
  var zip_REPZ_3_10 = 17;
  var zip_REPZ_11_138 = 18;
  var zip_HEAP_SIZE = 2 * zip_L_CODES + 1;
  var zip_H_SHIFT = parseInt((zip_HASH_BITS + zip_MIN_MATCH - 1) /
  			   zip_MIN_MATCH);
  
  /* variables */
  var zip_free_queue;
  var zip_qhead, zip_qtail;
  var zip_initflag;
  var zip_outbuf = null;
  var zip_outcnt, zip_outoff;
  var zip_complete;
  var zip_window;
  var zip_d_buf;
  var zip_l_buf;
  var zip_prev;
  var zip_bi_buf;
  var zip_bi_valid;
  var zip_block_start;
  var zip_ins_h;
  var zip_hash_head;
  var zip_prev_match;
  var zip_match_available;
  var zip_match_length;
  var zip_prev_length;
  var zip_strstart;
  var zip_match_start;
  var zip_eofile;
  var zip_lookahead;
  var zip_max_chain_length;
  var zip_max_lazy_match;
  var zip_compr_level;
  var zip_good_match;
  var zip_nice_match;
  var zip_dyn_ltree;
  var zip_dyn_dtree;
  var zip_static_ltree;
  var zip_static_dtree;
  var zip_bl_tree;
  var zip_l_desc;
  var zip_d_desc;
  var zip_bl_desc;
  var zip_bl_count;
  var zip_heap;
  var zip_heap_len;
  var zip_heap_max;
  var zip_depth;
  var zip_length_code;
  var zip_dist_code;
  var zip_base_length;
  var zip_base_dist;
  var zip_flag_buf;
  var zip_last_lit;
  var zip_last_dist;
  var zip_last_flags;
  var zip_flags;
  var zip_flag_bit;
  var zip_opt_len;
  var zip_static_len;
  var zip_deflate_data;
  var zip_deflate_pos;
  
  /* constant tables */
  var zip_extra_lbits = new Array(
      0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0);
  var zip_extra_dbits = new Array(
      0,0,0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13);
  var zip_extra_blbits = new Array(
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7);
  var zip_bl_order = new Array(
      16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15);
  var zip_configuration_table = new Array(
  	new zip_DeflateConfiguration(0,    0,   0,    0),
  	new zip_DeflateConfiguration(4,    4,   8,    4),
  	new zip_DeflateConfiguration(4,    5,  16,    8),
  	new zip_DeflateConfiguration(4,    6,  32,   32),
  	new zip_DeflateConfiguration(4,    4,  16,   16),
  	new zip_DeflateConfiguration(8,   16,  32,   32),
  	new zip_DeflateConfiguration(8,   16, 128,  128),
  	new zip_DeflateConfiguration(8,   32, 128,  256),
  	new zip_DeflateConfiguration(32, 128, 258, 1024),
  	new zip_DeflateConfiguration(32, 258, 258, 4096));
  
  /* objects (deflate) */
  
  function zip_DeflateCT() {
      this.fc = 0; // frequency count or bit string
      this.dl = 0; // father node in Huffman tree or length of bit string
  }
  
  function zip_DeflateTreeDesc() {
      this.dyn_tree = null;	// the dynamic tree
      this.static_tree = null;	// corresponding static tree or NULL
      this.extra_bits = null;	// extra bits for each code or NULL
      this.extra_base = 0;	// base index for extra_bits
      this.elems = 0;		// max number of elements in the tree
      this.max_length = 0;	// max bit length for the codes
      this.max_code = 0;		// largest code with non zero frequency
  }
  
  /* Values for max_lazy_match, good_match and max_chain_length, depending on
   * the desired pack level (0..9). The values given below have been tuned to
   * exclude worst case performance for pathological files. Better values may be
   * found for specific files.
   */
  function zip_DeflateConfiguration(a, b, c, d) {
      this.good_length = a; // reduce lazy search above this match length
      this.max_lazy = b;    // do not perform lazy search above this match length
      this.nice_length = c; // quit search above this match length
      this.max_chain = d;
  }
  
  function zip_DeflateBuffer() {
      this.next = null;
      this.len = 0;
      this.ptr = new Array(zip_OUTBUFSIZ);
      this.off = 0;
  }
  
  /* routines (deflate) */
  
  function zip_deflate_start(level) {
      var i;
  
      if(!level)
  	level = zip_DEFAULT_LEVEL;
      else if(level < 1)
  	level = 1;
      else if(level > 9)
  	level = 9;
  
      zip_compr_level = level;
      zip_initflag = false;
      zip_eofile = false;
      if(zip_outbuf != null)
  	return;
  
      zip_free_queue = zip_qhead = zip_qtail = null;
      zip_outbuf = new Array(zip_OUTBUFSIZ);
      zip_window = new Array(zip_window_size);
      zip_d_buf = new Array(zip_DIST_BUFSIZE);
      zip_l_buf = new Array(zip_INBUFSIZ + zip_INBUF_EXTRA);
      zip_prev = new Array(1 << zip_BITS);
      zip_dyn_ltree = new Array(zip_HEAP_SIZE);
      for(i = 0; i < zip_HEAP_SIZE; i++)
  	zip_dyn_ltree[i] = new zip_DeflateCT();
      zip_dyn_dtree = new Array(2*zip_D_CODES+1);
      for(i = 0; i < 2*zip_D_CODES+1; i++)
  	zip_dyn_dtree[i] = new zip_DeflateCT();
      zip_static_ltree = new Array(zip_L_CODES+2);
      for(i = 0; i < zip_L_CODES+2; i++)
  	zip_static_ltree[i] = new zip_DeflateCT();
      zip_static_dtree = new Array(zip_D_CODES);
      for(i = 0; i < zip_D_CODES; i++)
  	zip_static_dtree[i] = new zip_DeflateCT();
      zip_bl_tree = new Array(2*zip_BL_CODES+1);
      for(i = 0; i < 2*zip_BL_CODES+1; i++)
  	zip_bl_tree[i] = new zip_DeflateCT();
      zip_l_desc = new zip_DeflateTreeDesc();
      zip_d_desc = new zip_DeflateTreeDesc();
      zip_bl_desc = new zip_DeflateTreeDesc();
      zip_bl_count = new Array(zip_MAX_BITS+1);
      zip_heap = new Array(2*zip_L_CODES+1);
      zip_depth = new Array(2*zip_L_CODES+1);
      zip_length_code = new Array(zip_MAX_MATCH-zip_MIN_MATCH+1);
      zip_dist_code = new Array(512);
      zip_base_length = new Array(zip_LENGTH_CODES);
      zip_base_dist = new Array(zip_D_CODES);
      zip_flag_buf = new Array(parseInt(zip_LIT_BUFSIZE / 8));
  }
  
  function zip_deflate_end() {
      zip_free_queue = zip_qhead = zip_qtail = null;
      zip_outbuf = null;
      zip_window = null;
      zip_d_buf = null;
      zip_l_buf = null;
      zip_prev = null;
      zip_dyn_ltree = null;
      zip_dyn_dtree = null;
      zip_static_ltree = null;
      zip_static_dtree = null;
      zip_bl_tree = null;
      zip_l_desc = null;
      zip_d_desc = null;
      zip_bl_desc = null;
      zip_bl_count = null;
      zip_heap = null;
      zip_depth = null;
      zip_length_code = null;
      zip_dist_code = null;
      zip_base_length = null;
      zip_base_dist = null;
      zip_flag_buf = null;
  }
  
  function zip_reuse_queue(p) {
      p.next = zip_free_queue;
      zip_free_queue = p;
  }
  
  function zip_new_queue() {
      var p;
  
      if(zip_free_queue != null)
      {
  	p = zip_free_queue;
  	zip_free_queue = zip_free_queue.next;
      }
      else
  	p = new zip_DeflateBuffer();
      p.next = null;
      p.len = p.off = 0;
  
      return p;
  }
  
  function zip_head1(i) {
      return zip_prev[zip_WSIZE + i];
  }
  
  function zip_head2(i, val) {
      return zip_prev[zip_WSIZE + i] = val;
  }
  
  /* put_byte is used for the compressed output, put_ubyte for the
   * uncompressed output. However unlzw() uses window for its
   * suffix table instead of its output buffer, so it does not use put_ubyte
   * (to be cleaned up).
   */
  function zip_put_byte(c) {
      zip_outbuf[zip_outoff + zip_outcnt++] = c;
      if(zip_outoff + zip_outcnt == zip_OUTBUFSIZ)
  	zip_qoutbuf();
  }
  
  /* Output a 16 bit value, lsb first */
  function zip_put_short(w) {
      w &= 0xffff;
      if(zip_outoff + zip_outcnt < zip_OUTBUFSIZ - 2) {
  	zip_outbuf[zip_outoff + zip_outcnt++] = (w & 0xff);
  	zip_outbuf[zip_outoff + zip_outcnt++] = (w >>> 8);
      } else {
  	zip_put_byte(w & 0xff);
  	zip_put_byte(w >>> 8);
      }
  }
  
  /* ==========================================================================
   * Insert string s in the dictionary and set match_head to the previous head
   * of the hash chain (the most recent string with same hash key). Return
   * the previous length of the hash chain.
   * IN  assertion: all calls to to INSERT_STRING are made with consecutive
   *    input characters and the first MIN_MATCH bytes of s are valid
   *    (except for the last MIN_MATCH-1 bytes of the input file).
   */
  function zip_INSERT_STRING() {
      zip_ins_h = ((zip_ins_h << zip_H_SHIFT)
  		 ^ (zip_window[zip_strstart + zip_MIN_MATCH - 1] & 0xff))
  	& zip_HASH_MASK;
      zip_hash_head = zip_head1(zip_ins_h);
      zip_prev[zip_strstart & zip_WMASK] = zip_hash_head;
      zip_head2(zip_ins_h, zip_strstart);
  }
  
  /* Send a code of the given tree. c and tree must not have side effects */
  function zip_SEND_CODE(c, tree) {
      zip_send_bits(tree[c].fc, tree[c].dl);
  }
  
  /* Mapping from a distance to a distance code. dist is the distance - 1 and
   * must not have side effects. dist_code[256] and dist_code[257] are never
   * used.
   */
  function zip_D_CODE(dist) {
      return (dist < 256 ? zip_dist_code[dist]
  	    : zip_dist_code[256 + (dist>>7)]) & 0xff;
  }
  
  /* ==========================================================================
   * Compares to subtrees, using the tree depth as tie breaker when
   * the subtrees have equal frequency. This minimizes the worst case length.
   */
  function zip_SMALLER(tree, n, m) {
      return tree[n].fc < tree[m].fc ||
        (tree[n].fc == tree[m].fc && zip_depth[n] <= zip_depth[m]);
  }
  
  /* ==========================================================================
   * read string data
   */
  function zip_read_buff(buff, offset, n) {
      var i;
      for(i = 0; i < n && zip_deflate_pos < zip_deflate_data.length; i++)
  	buff[offset + i] =
  	    zip_deflate_data.charCodeAt(zip_deflate_pos++) & 0xff;
      return i;
  }
  
  /* ==========================================================================
   * Initialize the "longest match" routines for a new file
   */
  function zip_lm_init() {
      var j;
  
      /* Initialize the hash table. */
      for(j = 0; j < zip_HASH_SIZE; j++)
  //	zip_head2(j, zip_NIL);
  	zip_prev[zip_WSIZE + j] = 0;
      /* prev will be initialized on the fly */
  
      /* Set the default configuration parameters:
       */
      zip_max_lazy_match = zip_configuration_table[zip_compr_level].max_lazy;
      zip_good_match     = zip_configuration_table[zip_compr_level].good_length;
      if(!zip_FULL_SEARCH)
  	zip_nice_match = zip_configuration_table[zip_compr_level].nice_length;
      zip_max_chain_length = zip_configuration_table[zip_compr_level].max_chain;
  
      zip_strstart = 0;
      zip_block_start = 0;
  
      zip_lookahead = zip_read_buff(zip_window, 0, 2 * zip_WSIZE);
      if(zip_lookahead <= 0) {
  	zip_eofile = true;
  	zip_lookahead = 0;
  	return;
      }
      zip_eofile = false;
      /* Make sure that we always have enough lookahead. This is important
       * if input comes from a device such as a tty.
       */
      while(zip_lookahead < zip_MIN_LOOKAHEAD && !zip_eofile)
  	zip_fill_window();
  
      /* If lookahead < MIN_MATCH, ins_h is garbage, but this is
       * not important since only literal bytes will be emitted.
       */
      zip_ins_h = 0;
      for(j = 0; j < zip_MIN_MATCH - 1; j++) {
  //      UPDATE_HASH(ins_h, window[j]);
  	zip_ins_h = ((zip_ins_h << zip_H_SHIFT) ^ (zip_window[j] & 0xff)) & zip_HASH_MASK;
      }
  }
  
  /* ==========================================================================
   * Set match_start to the longest match starting at the given string and
   * return its length. Matches shorter or equal to prev_length are discarded,
   * in which case the result is equal to prev_length and match_start is
   * garbage.
   * IN assertions: cur_match is the head of the hash chain for the current
   *   string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1
   */
  function zip_longest_match(cur_match) {
      var chain_length = zip_max_chain_length; // max hash chain length
      var scanp = zip_strstart; // current string
      var matchp;		// matched string
      var len;		// length of current match
      var best_len = zip_prev_length;	// best match length so far
  
      /* Stop when cur_match becomes <= limit. To simplify the code,
       * we prevent matches with the string of window index 0.
       */
      var limit = (zip_strstart > zip_MAX_DIST ? zip_strstart - zip_MAX_DIST : zip_NIL);
  
      var strendp = zip_strstart + zip_MAX_MATCH;
      var scan_end1 = zip_window[scanp + best_len - 1];
      var scan_end  = zip_window[scanp + best_len];
  
      /* Do not waste too much time if we already have a good match: */
      if(zip_prev_length >= zip_good_match)
  	chain_length >>= 2;
  
  //  Assert(encoder->strstart <= window_size-MIN_LOOKAHEAD, "insufficient lookahead");
  
      do {
  //    Assert(cur_match < encoder->strstart, "no future");
  	matchp = cur_match;
  
  	/* Skip to next match if the match length cannot increase
  	    * or if the match length is less than 2:
  	*/
  	if(zip_window[matchp + best_len]	!= scan_end  ||
  	   zip_window[matchp + best_len - 1]	!= scan_end1 ||
  	   zip_window[matchp]			!= zip_window[scanp] ||
  	   zip_window[++matchp]			!= zip_window[scanp + 1]) {
  	    continue;
  	}
  
  	/* The check at best_len-1 can be removed because it will be made
           * again later. (This heuristic is not always a win.)
           * It is not necessary to compare scan[2] and match[2] since they
           * are always equal when the other bytes match, given that
           * the hash keys are equal and that HASH_BITS >= 8.
           */
  	scanp += 2;
  	matchp++;
  
  	/* We check for insufficient lookahead only every 8th comparison;
           * the 256th check will be made at strstart+258.
           */
  	do {
  	} while(zip_window[++scanp] == zip_window[++matchp] &&
  		zip_window[++scanp] == zip_window[++matchp] &&
  		zip_window[++scanp] == zip_window[++matchp] &&
  		zip_window[++scanp] == zip_window[++matchp] &&
  		zip_window[++scanp] == zip_window[++matchp] &&
  		zip_window[++scanp] == zip_window[++matchp] &&
  		zip_window[++scanp] == zip_window[++matchp] &&
  		zip_window[++scanp] == zip_window[++matchp] &&
  		scanp < strendp);
  
        len = zip_MAX_MATCH - (strendp - scanp);
        scanp = strendp - zip_MAX_MATCH;
  
        if(len > best_len) {
  	  zip_match_start = cur_match;
  	  best_len = len;
  	  if(zip_FULL_SEARCH) {
  	      if(len >= zip_MAX_MATCH) break;
  	  } else {
  	      if(len >= zip_nice_match) break;
  	  }
  
  	  scan_end1  = zip_window[scanp + best_len-1];
  	  scan_end   = zip_window[scanp + best_len];
        }
      } while((cur_match = zip_prev[cur_match & zip_WMASK]) > limit
  	    && --chain_length != 0);
  
      return best_len;
  }
  
  /* ==========================================================================
   * Fill the window when the lookahead becomes insufficient.
   * Updates strstart and lookahead, and sets eofile if end of input file.
   * IN assertion: lookahead < MIN_LOOKAHEAD && strstart + lookahead > 0
   * OUT assertions: at least one byte has been read, or eofile is set;
   *    file reads are performed for at least two bytes (required for the
   *    translate_eol option).
   */
  function zip_fill_window() {
      var n, m;
  
      // Amount of free space at the end of the window.
      var more = zip_window_size - zip_lookahead - zip_strstart;
  
      /* If the window is almost full and there is insufficient lookahead,
       * move the upper half to the lower one to make room in the upper half.
       */
      if(more == -1) {
  	/* Very unlikely, but possible on 16 bit machine if strstart == 0
           * and lookahead == 1 (input done one byte at time)
           */
  	more--;
      } else if(zip_strstart >= zip_WSIZE + zip_MAX_DIST) {
  	/* By the IN assertion, the window is not empty so we can't confuse
           * more == 0 with more == 64K on a 16 bit machine.
           */
  //	Assert(window_size == (ulg)2*WSIZE, "no sliding with BIG_MEM");
  
  //	System.arraycopy(window, WSIZE, window, 0, WSIZE);
  	for(n = 0; n < zip_WSIZE; n++)
  	    zip_window[n] = zip_window[n + zip_WSIZE];
        
  	zip_match_start -= zip_WSIZE;
  	zip_strstart    -= zip_WSIZE; /* we now have strstart >= MAX_DIST: */
  	zip_block_start -= zip_WSIZE;
  
  	for(n = 0; n < zip_HASH_SIZE; n++) {
  	    m = zip_head1(n);
  	    zip_head2(n, m >= zip_WSIZE ? m - zip_WSIZE : zip_NIL);
  	}
  	for(n = 0; n < zip_WSIZE; n++) {
  	    /* If n is not on any hash chain, prev[n] is garbage but
  	     * its value will never be used.
  	     */
  	    m = zip_prev[n];
  	    zip_prev[n] = (m >= zip_WSIZE ? m - zip_WSIZE : zip_NIL);
  	}
  	more += zip_WSIZE;
      }
      // At this point, more >= 2
      if(!zip_eofile) {
  	n = zip_read_buff(zip_window, zip_strstart + zip_lookahead, more);
  	if(n <= 0)
  	    zip_eofile = true;
  	else
  	    zip_lookahead += n;
      }
  }
  
  /* ==========================================================================
   * Processes a new input file and return its compressed length. This
   * function does not perform lazy evaluationof matches and inserts
   * new strings in the dictionary only for unmatched strings or for short
   * matches. It is used only for the fast compression options.
   */
  function zip_deflate_fast() {
      while(zip_lookahead != 0 && zip_qhead == null) {
  	var flush; // set if current block must be flushed
  
  	/* Insert the string window[strstart .. strstart+2] in the
  	 * dictionary, and set hash_head to the head of the hash chain:
  	 */
  	zip_INSERT_STRING();
  
  	/* Find the longest match, discarding those <= prev_length.
  	 * At this point we have always match_length < MIN_MATCH
  	 */
  	if(zip_hash_head != zip_NIL &&
  	   zip_strstart - zip_hash_head <= zip_MAX_DIST) {
  	    /* To simplify the code, we prevent matches with the string
  	     * of window index 0 (in particular we have to avoid a match
  	     * of the string with itself at the start of the input file).
  	     */
  	    zip_match_length = zip_longest_match(zip_hash_head);
  	    /* longest_match() sets match_start */
  	    if(zip_match_length > zip_lookahead)
  		zip_match_length = zip_lookahead;
  	}
  	if(zip_match_length >= zip_MIN_MATCH) {
  //	    check_match(strstart, match_start, match_length);
  
  	    flush = zip_ct_tally(zip_strstart - zip_match_start,
  				 zip_match_length - zip_MIN_MATCH);
  	    zip_lookahead -= zip_match_length;
  
  	    /* Insert new strings in the hash table only if the match length
  	     * is not too large. This saves time but degrades compression.
  	     */
  	    if(zip_match_length <= zip_max_lazy_match) {
  		zip_match_length--; // string at strstart already in hash table
  		do {
  		    zip_strstart++;
  		    zip_INSERT_STRING();
  		    /* strstart never exceeds WSIZE-MAX_MATCH, so there are
  		     * always MIN_MATCH bytes ahead. If lookahead < MIN_MATCH
  		     * these bytes are garbage, but it does not matter since
  		     * the next lookahead bytes will be emitted as literals.
  		     */
  		} while(--zip_match_length != 0);
  		zip_strstart++;
  	    } else {
  		zip_strstart += zip_match_length;
  		zip_match_length = 0;
  		zip_ins_h = zip_window[zip_strstart] & 0xff;
  //		UPDATE_HASH(ins_h, window[strstart + 1]);
  		zip_ins_h = ((zip_ins_h<<zip_H_SHIFT) ^ (zip_window[zip_strstart + 1] & 0xff)) & zip_HASH_MASK;
  
  //#if MIN_MATCH != 3
  //		Call UPDATE_HASH() MIN_MATCH-3 more times
  //#endif
  
  	    }
  	} else {
  	    /* No match, output a literal byte */
  	    flush = zip_ct_tally(0, zip_window[zip_strstart] & 0xff);
  	    zip_lookahead--;
  	    zip_strstart++;
  	}
  	if(flush) {
  	    zip_flush_block(0);
  	    zip_block_start = zip_strstart;
  	}
  
  	/* Make sure that we always have enough lookahead, except
  	 * at the end of the input file. We need MAX_MATCH bytes
  	 * for the next match, plus MIN_MATCH bytes to insert the
  	 * string following the next match.
  	 */
  	while(zip_lookahead < zip_MIN_LOOKAHEAD && !zip_eofile)
  	    zip_fill_window();
      }
  }
  
  function zip_deflate_better() {
      /* Process the input block. */
      while(zip_lookahead != 0 && zip_qhead == null) {
  	/* Insert the string window[strstart .. strstart+2] in the
  	 * dictionary, and set hash_head to the head of the hash chain:
  	 */
  	zip_INSERT_STRING();
  
  	/* Find the longest match, discarding those <= prev_length.
  	 */
  	zip_prev_length = zip_match_length;
  	zip_prev_match = zip_match_start;
  	zip_match_length = zip_MIN_MATCH - 1;
  
  	if(zip_hash_head != zip_NIL &&
  	   zip_prev_length < zip_max_lazy_match &&
  	   zip_strstart - zip_hash_head <= zip_MAX_DIST) {
  	    /* To simplify the code, we prevent matches with the string
  	     * of window index 0 (in particular we have to avoid a match
  	     * of the string with itself at the start of the input file).
  	     */
  	    zip_match_length = zip_longest_match(zip_hash_head);
  	    /* longest_match() sets match_start */
  	    if(zip_match_length > zip_lookahead)
  		zip_match_length = zip_lookahead;
  
  	    /* Ignore a length 3 match if it is too distant: */
  	    if(zip_match_length == zip_MIN_MATCH &&
  	       zip_strstart - zip_match_start > zip_TOO_FAR) {
  		/* If prev_match is also MIN_MATCH, match_start is garbage
  		 * but we will ignore the current match anyway.
  		 */
  		zip_match_length--;
  	    }
  	}
  	/* If there was a match at the previous step and the current
  	 * match is not better, output the previous match:
  	 */
  	if(zip_prev_length >= zip_MIN_MATCH &&
  	   zip_match_length <= zip_prev_length) {
  	    var flush; // set if current block must be flushed
  
  //	    check_match(strstart - 1, prev_match, prev_length);
  	    flush = zip_ct_tally(zip_strstart - 1 - zip_prev_match,
  				 zip_prev_length - zip_MIN_MATCH);
  
  	    /* Insert in hash table all strings up to the end of the match.
  	     * strstart-1 and strstart are already inserted.
  	     */
  	    zip_lookahead -= zip_prev_length - 1;
  	    zip_prev_length -= 2;
  	    do {
  		zip_strstart++;
  		zip_INSERT_STRING();
  		/* strstart never exceeds WSIZE-MAX_MATCH, so there are
  		 * always MIN_MATCH bytes ahead. If lookahead < MIN_MATCH
  		 * these bytes are garbage, but it does not matter since the
  		 * next lookahead bytes will always be emitted as literals.
  		 */
  	    } while(--zip_prev_length != 0);
  	    zip_match_available = 0;
  	    zip_match_length = zip_MIN_MATCH - 1;
  	    zip_strstart++;
  	    if(flush) {
  		zip_flush_block(0);
  		zip_block_start = zip_strstart;
  	    }
  	} else if(zip_match_available != 0) {
  	    /* If there was no match at the previous position, output a
  	     * single literal. If there was a match but the current match
  	     * is longer, truncate the previous match to a single literal.
  	     */
  	    if(zip_ct_tally(0, zip_window[zip_strstart - 1] & 0xff)) {
  		zip_flush_block(0);
  		zip_block_start = zip_strstart;
  	    }
  	    zip_strstart++;
  	    zip_lookahead--;
  	} else {
  	    /* There is no previous match to compare with, wait for
  	     * the next step to decide.
  	     */
  	    zip_match_available = 1;
  	    zip_strstart++;
  	    zip_lookahead--;
  	}
  
  	/* Make sure that we always have enough lookahead, except
  	 * at the end of the input file. We need MAX_MATCH bytes
  	 * for the next match, plus MIN_MATCH bytes to insert the
  	 * string following the next match.
  	 */
  	while(zip_lookahead < zip_MIN_LOOKAHEAD && !zip_eofile)
  	    zip_fill_window();
      }
  }
  
  function zip_init_deflate() {
      if(zip_eofile)
  	return;
      zip_bi_buf = 0;
      zip_bi_valid = 0;
      zip_ct_init();
      zip_lm_init();
  
      zip_qhead = null;
      zip_outcnt = 0;
      zip_outoff = 0;
  
      if(zip_compr_level <= 3)
      {
  	zip_prev_length = zip_MIN_MATCH - 1;
  	zip_match_length = 0;
      }
      else
      {
  	zip_match_length = zip_MIN_MATCH - 1;
  	zip_match_available = 0;
      }
  
      zip_complete = false;
  }
  
  /* ==========================================================================
   * Same as above, but achieves better compression. We use a lazy
   * evaluation for matches: a match is finally adopted only if there is
   * no better match at the next window position.
   */
  function zip_deflate_internal(buff, off, buff_size) {
      var n;
  
      if(!zip_initflag)
      {
  	zip_init_deflate();
  	zip_initflag = true;
  	if(zip_lookahead == 0) { // empty
  	    zip_complete = true;
  	    return 0;
  	}
      }
  
      if((n = zip_qcopy(buff, off, buff_size)) == buff_size)
  	return buff_size;
  
      if(zip_complete)
  	return n;
  
      if(zip_compr_level <= 3) // optimized for speed
  	zip_deflate_fast();
      else
  	zip_deflate_better();
      if(zip_lookahead == 0) {
  	if(zip_match_available != 0)
  	    zip_ct_tally(0, zip_window[zip_strstart - 1] & 0xff);
  	zip_flush_block(1);
  	zip_complete = true;
      }
      return n + zip_qcopy(buff, n + off, buff_size - n);
  }
  
  function zip_qcopy(buff, off, buff_size) {
      var n, i, j;
  
      n = 0;
      while(zip_qhead != null && n < buff_size)
      {
  	i = buff_size - n;
  	if(i > zip_qhead.len)
  	    i = zip_qhead.len;
  //      System.arraycopy(qhead.ptr, qhead.off, buff, off + n, i);
  	for(j = 0; j < i; j++)
  	    buff[off + n + j] = zip_qhead.ptr[zip_qhead.off + j];
  	
  	zip_qhead.off += i;
  	zip_qhead.len -= i;
  	n += i;
  	if(zip_qhead.len == 0) {
  	    var p;
  	    p = zip_qhead;
  	    zip_qhead = zip_qhead.next;
  	    zip_reuse_queue(p);
  	}
      }
  
      if(n == buff_size)
  	return n;
  
      if(zip_outoff < zip_outcnt) {
  	i = buff_size - n;
  	if(i > zip_outcnt - zip_outoff)
  	    i = zip_outcnt - zip_outoff;
  	// System.arraycopy(outbuf, outoff, buff, off + n, i);
  	for(j = 0; j < i; j++)
  	    buff[off + n + j] = zip_outbuf[zip_outoff + j];
  	zip_outoff += i;
  	n += i;
  	if(zip_outcnt == zip_outoff)
  	    zip_outcnt = zip_outoff = 0;
      }
      return n;
  }
  
  /* ==========================================================================
   * Allocate the match buffer, initialize the various tables and save the
   * location of the internal file attribute (ascii/binary) and method
   * (DEFLATE/STORE).
   */
  function zip_ct_init() {
      var n;	// iterates over tree elements
      var bits;	// bit counter
      var length;	// length value
      var code;	// code value
      var dist;	// distance index
  
      if(zip_static_dtree[0].dl != 0) return; // ct_init already called
  
      zip_l_desc.dyn_tree		= zip_dyn_ltree;
      zip_l_desc.static_tree	= zip_static_ltree;
      zip_l_desc.extra_bits	= zip_extra_lbits;
      zip_l_desc.extra_base	= zip_LITERALS + 1;
      zip_l_desc.elems		= zip_L_CODES;
      zip_l_desc.max_length	= zip_MAX_BITS;
      zip_l_desc.max_code		= 0;
  
      zip_d_desc.dyn_tree		= zip_dyn_dtree;
      zip_d_desc.static_tree	= zip_static_dtree;
      zip_d_desc.extra_bits	= zip_extra_dbits;
      zip_d_desc.extra_base	= 0;
      zip_d_desc.elems		= zip_D_CODES;
      zip_d_desc.max_length	= zip_MAX_BITS;
      zip_d_desc.max_code		= 0;
  
      zip_bl_desc.dyn_tree	= zip_bl_tree;
      zip_bl_desc.static_tree	= null;
      zip_bl_desc.extra_bits	= zip_extra_blbits;
      zip_bl_desc.extra_base	= 0;
      zip_bl_desc.elems		= zip_BL_CODES;
      zip_bl_desc.max_length	= zip_MAX_BL_BITS;
      zip_bl_desc.max_code	= 0;
  
      // Initialize the mapping length (0..255) -> length code (0..28)
      length = 0;
      for(code = 0; code < zip_LENGTH_CODES-1; code++) {
  	zip_base_length[code] = length;
  	for(n = 0; n < (1<<zip_extra_lbits[code]); n++)
  	    zip_length_code[length++] = code;
      }
      // Assert (length == 256, "ct_init: length != 256");
  
      /* Note that the length 255 (match length 258) can be represented
       * in two different ways: code 284 + 5 bits or code 285, so we
       * overwrite length_code[255] to use the best encoding:
       */
      zip_length_code[length-1] = code;
  
      /* Initialize the mapping dist (0..32K) -> dist code (0..29) */
      dist = 0;
      for(code = 0 ; code < 16; code++) {
  	zip_base_dist[code] = dist;
  	for(n = 0; n < (1<<zip_extra_dbits[code]); n++) {
  	    zip_dist_code[dist++] = code;
  	}
      }
      // Assert (dist == 256, "ct_init: dist != 256");
      dist >>= 7; // from now on, all distances are divided by 128
      for( ; code < zip_D_CODES; code++) {
  	zip_base_dist[code] = dist << 7;
  	for(n = 0; n < (1<<(zip_extra_dbits[code]-7)); n++)
  	    zip_dist_code[256 + dist++] = code;
      }
      // Assert (dist == 256, "ct_init: 256+dist != 512");
  
      // Construct the codes of the static literal tree
      for(bits = 0; bits <= zip_MAX_BITS; bits++)
  	zip_bl_count[bits] = 0;
      n = 0;
      while(n <= 143) { zip_static_ltree[n++].dl = 8; zip_bl_count[8]++; }
      while(n <= 255) { zip_static_ltree[n++].dl = 9; zip_bl_count[9]++; }
      while(n <= 279) { zip_static_ltree[n++].dl = 7; zip_bl_count[7]++; }
      while(n <= 287) { zip_static_ltree[n++].dl = 8; zip_bl_count[8]++; }
      /* Codes 286 and 287 do not exist, but we must include them in the
       * tree construction to get a canonical Huffman tree (longest code
       * all ones)
       */
      zip_gen_codes(zip_static_ltree, zip_L_CODES + 1);
  
      /* The static distance tree is trivial: */
      for(n = 0; n < zip_D_CODES; n++) {
  	zip_static_dtree[n].dl = 5;
  	zip_static_dtree[n].fc = zip_bi_reverse(n, 5);
      }
  
      // Initialize the first block of the first file:
      zip_init_block();
  }
  
  /* ==========================================================================
   * Initialize a new block.
   */
  function zip_init_block() {
      var n; // iterates over tree elements
  
      // Initialize the trees.
      for(n = 0; n < zip_L_CODES;  n++) zip_dyn_ltree[n].fc = 0;
      for(n = 0; n < zip_D_CODES;  n++) zip_dyn_dtree[n].fc = 0;
      for(n = 0; n < zip_BL_CODES; n++) zip_bl_tree[n].fc = 0;
  
      zip_dyn_ltree[zip_END_BLOCK].fc = 1;
      zip_opt_len = zip_static_len = 0;
      zip_last_lit = zip_last_dist = zip_last_flags = 0;
      zip_flags = 0;
      zip_flag_bit = 1;
  }
  
  /* ==========================================================================
   * Restore the heap property by moving down the tree starting at node k,
   * exchanging a node with the smallest of its two sons if necessary, stopping
   * when the heap property is re-established (each father smaller than its
   * two sons).
   */
  function zip_pqdownheap(
      tree,	// the tree to restore
      k) {	// node to move down
      var v = zip_heap[k];
      var j = k << 1;	// left son of k
  
      while(j <= zip_heap_len) {
  	// Set j to the smallest of the two sons:
  	if(j < zip_heap_len &&
  	   zip_SMALLER(tree, zip_heap[j + 1], zip_heap[j]))
  	    j++;
  
  	// Exit if v is smaller than both sons
  	if(zip_SMALLER(tree, v, zip_heap[j]))
  	    break;
  
  	// Exchange v with the smallest son
  	zip_heap[k] = zip_heap[j];
  	k = j;
  
  	// And continue down the tree, setting j to the left son of k
  	j <<= 1;
      }
      zip_heap[k] = v;
  }
  
  /* ==========================================================================
   * Compute the optimal bit lengths for a tree and update the total bit length
   * for the current block.
   * IN assertion: the fields freq and dad are set, heap[heap_max] and
   *    above are the tree nodes sorted by increasing frequency.
   * OUT assertions: the field len is set to the optimal bit length, the
   *     array bl_count contains the frequencies for each bit length.
   *     The length opt_len is updated; static_len is also updated if stree is
   *     not null.
   */
  function zip_gen_bitlen(desc) { // the tree descriptor
      var tree		= desc.dyn_tree;
      var extra		= desc.extra_bits;
      var base		= desc.extra_base;
      var max_code	= desc.max_code;
      var max_length	= desc.max_length;
      var stree		= desc.static_tree;
      var h;		// heap index
      var n, m;		// iterate over the tree elements
      var bits;		// bit length
      var xbits;		// extra bits
      var f;		// frequency
      var overflow = 0;	// number of elements with bit length too large
  
      for(bits = 0; bits <= zip_MAX_BITS; bits++)
  	zip_bl_count[bits] = 0;
  
      /* In a first pass, compute the optimal bit lengths (which may
       * overflow in the case of the bit length tree).
       */
      tree[zip_heap[zip_heap_max]].dl = 0; // root of the heap
  
      for(h = zip_heap_max + 1; h < zip_HEAP_SIZE; h++) {
  	n = zip_heap[h];
  	bits = tree[tree[n].dl].dl + 1;
  	if(bits > max_length) {
  	    bits = max_length;
  	    overflow++;
  	}
  	tree[n].dl = bits;
  	// We overwrite tree[n].dl which is no longer needed
  
  	if(n > max_code)
  	    continue; // not a leaf node
  
  	zip_bl_count[bits]++;
  	xbits = 0;
  	if(n >= base)
  	    xbits = extra[n - base];
  	f = tree[n].fc;
  	zip_opt_len += f * (bits + xbits);
  	if(stree != null)
  	    zip_static_len += f * (stree[n].dl + xbits);
      }
      if(overflow == 0)
  	return;
  
      // This happens for example on obj2 and pic of the Calgary corpus
  
      // Find the first bit length which could increase:
      do {
  	bits = max_length - 1;
  	while(zip_bl_count[bits] == 0)
  	    bits--;
  	zip_bl_count[bits]--;		// move one leaf down the tree
  	zip_bl_count[bits + 1] += 2;	// move one overflow item as its brother
  	zip_bl_count[max_length]--;
  	/* The brother of the overflow item also moves one step up,
  	 * but this does not affect bl_count[max_length]
  	 */
  	overflow -= 2;
      } while(overflow > 0);
  
      /* Now recompute all bit lengths, scanning in increasing frequency.
       * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all
       * lengths instead of fixing only the wrong ones. This idea is taken
       * from 'ar' written by Haruhiko Okumura.)
       */
      for(bits = max_length; bits != 0; bits--) {
  	n = zip_bl_count[bits];
  	while(n != 0) {
  	    m = zip_heap[--h];
  	    if(m > max_code)
  		continue;
  	    if(tree[m].dl != bits) {
  		zip_opt_len += (bits - tree[m].dl) * tree[m].fc;
  		tree[m].fc = bits;
  	    }
  	    n--;
  	}
      }
  }
  
    /* ==========================================================================
     * Generate the codes for a given tree and bit counts (which need not be
     * optimal).
     * IN assertion: the array bl_count contains the bit length statistics for
     * the given tree and the field len is set for all tree elements.
     * OUT assertion: the field code is set for all tree elements of non
     *     zero code length.
     */
  function zip_gen_codes(tree,	// the tree to decorate
  		   max_code) {	// largest code with non zero frequency
      var next_code = new Array(zip_MAX_BITS+1); // next code value for each bit length
      var code = 0;		// running code value
      var bits;			// bit index
      var n;			// code index
  
      /* The distribution counts are first used to generate the code values
       * without bit reversal.
       */
      for(bits = 1; bits <= zip_MAX_BITS; bits++) {
  	code = ((code + zip_bl_count[bits-1]) << 1);
  	next_code[bits] = code;
      }
  
      /* Check that the bit counts in bl_count are consistent. The last code
       * must be all ones.
       */
  //    Assert (code + encoder->bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1,
  //	    "inconsistent bit counts");
  //    Tracev((stderr,"\ngen_codes: max_code %d ", max_code));
  
      for(n = 0; n <= max_code; n++) {
  	var len = tree[n].dl;
  	if(len == 0)
  	    continue;
  	// Now reverse the bits
  	tree[n].fc = zip_bi_reverse(next_code[len]++, len);
  
  //      Tracec(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
  //	  n, (isgraph(n) ? n : ' '), len, tree[n].fc, next_code[len]-1));
      }
  }
  
  /* ==========================================================================
   * Construct one Huffman tree and assigns the code bit strings and lengths.
   * Update the total bit length for the current block.
   * IN assertion: the field freq is set for all tree elements.
   * OUT assertions: the fields len and code are set to the optimal bit length
   *     and corresponding code. The length opt_len is updated; static_len is
   *     also updated if stree is not null. The field max_code is set.
   */
  function zip_build_tree(desc) { // the tree descriptor
      var tree	= desc.dyn_tree;
      var stree	= desc.static_tree;
      var elems	= desc.elems;
      var n, m;		// iterate over heap elements
      var max_code = -1;	// largest code with non zero frequency
      var node = elems;	// next internal node of the tree
  
      /* Construct the initial heap, with least frequent element in
       * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1].
       * heap[0] is not used.
       */
      zip_heap_len = 0;
      zip_heap_max = zip_HEAP_SIZE;
  
      for(n = 0; n < elems; n++) {
  	if(tree[n].fc != 0) {
  	    zip_heap[++zip_heap_len] = max_code = n;
  	    zip_depth[n] = 0;
  	} else
  	    tree[n].dl = 0;
      }
  
      /* The pkzip format requires that at least one distance code exists,
       * and that at least one bit should be sent even if there is only one
       * possible code. So to avoid special checks later on we force at least
       * two codes of non zero frequency.
       */
      while(zip_heap_len < 2) {
  	var xnew = zip_heap[++zip_heap_len] = (max_code < 2 ? ++max_code : 0);
  	tree[xnew].fc = 1;
  	zip_depth[xnew] = 0;
  	zip_opt_len--;
  	if(stree != null)
  	    zip_static_len -= stree[xnew].dl;
  	// new is 0 or 1 so it does not have extra bits
      }
      desc.max_code = max_code;
  
      /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,
       * establish sub-heaps of increasing lengths:
       */
      for(n = zip_heap_len >> 1; n >= 1; n--)
  	zip_pqdownheap(tree, n);
  
      /* Construct the Huffman tree by repeatedly combining the least two
       * frequent nodes.
       */
      do {
  	n = zip_heap[zip_SMALLEST];
  	zip_heap[zip_SMALLEST] = zip_heap[zip_heap_len--];
  	zip_pqdownheap(tree, zip_SMALLEST);
  
  	m = zip_heap[zip_SMALLEST];  // m = node of next least frequency
  
  	// keep the nodes sorted by frequency
  	zip_heap[--zip_heap_max] = n;
  	zip_heap[--zip_heap_max] = m;
  
  	// Create a new node father of n and m
  	tree[node].fc = tree[n].fc + tree[m].fc;
  //	depth[node] = (char)(MAX(depth[n], depth[m]) + 1);
  	if(zip_depth[n] > zip_depth[m] + 1)
  	    zip_depth[node] = zip_depth[n];
  	else
  	    zip_depth[node] = zip_depth[m] + 1;
  	tree[n].dl = tree[m].dl = node;
  
  	// and insert the new node in the heap
  	zip_heap[zip_SMALLEST] = node++;
  	zip_pqdownheap(tree, zip_SMALLEST);
  
      } while(zip_heap_len >= 2);
  
      zip_heap[--zip_heap_max] = zip_heap[zip_SMALLEST];
  
      /* At this point, the fields freq and dad are set. We can now
       * generate the bit lengths.
       */
      zip_gen_bitlen(desc);
  
      // The field len is now set, we can generate the bit codes
      zip_gen_codes(tree, max_code);
  }
  
  /* ==========================================================================
   * Scan a literal or distance tree to determine the frequencies of the codes
   * in the bit length tree. Updates opt_len to take into account the repeat
   * counts. (The contribution of the bit length codes will be added later
   * during the construction of bl_tree.)
   */
  function zip_scan_tree(tree,// the tree to be scanned
  		       max_code) {  // and its largest code of non zero frequency
      var n;			// iterates over all tree elements
      var prevlen = -1;		// last emitted length
      var curlen;			// length of current code
      var nextlen = tree[0].dl;	// length of next code
      var count = 0;		// repeat count of the current code
      var max_count = 7;		// max repeat count
      var min_count = 4;		// min repeat count
  
      if(nextlen == 0) {
  	max_count = 138;
  	min_count = 3;
      }
      tree[max_code + 1].dl = 0xffff; // guard
  
      for(n = 0; n <= max_code; n++) {
  	curlen = nextlen;
  	nextlen = tree[n + 1].dl;
  	if(++count < max_count && curlen == nextlen)
  	    continue;
  	else if(count < min_count)
  	    zip_bl_tree[curlen].fc += count;
  	else if(curlen != 0) {
  	    if(curlen != prevlen)
  		zip_bl_tree[curlen].fc++;
  	    zip_bl_tree[zip_REP_3_6].fc++;
  	} else if(count <= 10)
  	    zip_bl_tree[zip_REPZ_3_10].fc++;
  	else
  	    zip_bl_tree[zip_REPZ_11_138].fc++;
  	count = 0; prevlen = curlen;
  	if(nextlen == 0) {
  	    max_count = 138;
  	    min_count = 3;
  	} else if(curlen == nextlen) {
  	    max_count = 6;
  	    min_count = 3;
  	} else {
  	    max_count = 7;
  	    min_count = 4;
  	}
      }
  }
  
    /* ==========================================================================
     * Send a literal or distance tree in compressed form, using the codes in
     * bl_tree.
     */
  function zip_send_tree(tree, // the tree to be scanned
  		   max_code) { // and its largest code of non zero frequency
      var n;			// iterates over all tree elements
      var prevlen = -1;		// last emitted length
      var curlen;			// length of current code
      var nextlen = tree[0].dl;	// length of next code
      var count = 0;		// repeat count of the current code
      var max_count = 7;		// max repeat count
      var min_count = 4;		// min repeat count
  
      /* tree[max_code+1].dl = -1; */  /* guard already set */
      if(nextlen == 0) {
        max_count = 138;
        min_count = 3;
      }
  
      for(n = 0; n <= max_code; n++) {
  	curlen = nextlen;
  	nextlen = tree[n+1].dl;
  	if(++count < max_count && curlen == nextlen) {
  	    continue;
  	} else if(count < min_count) {
  	    do { zip_SEND_CODE(curlen, zip_bl_tree); } while(--count != 0);
  	} else if(curlen != 0) {
  	    if(curlen != prevlen) {
  		zip_SEND_CODE(curlen, zip_bl_tree);
  		count--;
  	    }
  	    // Assert(count >= 3 && count <= 6, " 3_6?");
  	    zip_SEND_CODE(zip_REP_3_6, zip_bl_tree);
  	    zip_send_bits(count - 3, 2);
  	} else if(count <= 10) {
  	    zip_SEND_CODE(zip_REPZ_3_10, zip_bl_tree);
  	    zip_send_bits(count-3, 3);
  	} else {
  	    zip_SEND_CODE(zip_REPZ_11_138, zip_bl_tree);
  	    zip_send_bits(count-11, 7);
  	}
  	count = 0;
  	prevlen = curlen;
  	if(nextlen == 0) {
  	    max_count = 138;
  	    min_count = 3;
  	} else if(curlen == nextlen) {
  	    max_count = 6;
  	    min_count = 3;
  	} else {
  	    max_count = 7;
  	    min_count = 4;
  	}
      }
  }
  
  /* ==========================================================================
   * Construct the Huffman tree for the bit lengths and return the index in
   * bl_order of the last bit length code to send.
   */
  function zip_build_bl_tree() {
      var max_blindex;  // index of last bit length code of non zero freq
  
      // Determine the bit length frequencies for literal and distance trees
      zip_scan_tree(zip_dyn_ltree, zip_l_desc.max_code);
      zip_scan_tree(zip_dyn_dtree, zip_d_desc.max_code);
  
      // Build the bit length tree:
      zip_build_tree(zip_bl_desc);
      /* opt_len now includes the length of the tree representations, except
       * the lengths of the bit lengths codes and the 5+5+4 bits for the counts.
       */
  
      /* Determine the number of bit length codes to send. The pkzip format
       * requires that at least 4 bit length codes be sent. (appnote.txt says
       * 3 but the actual value used is 4.)
       */
      for(max_blindex = zip_BL_CODES-1; max_blindex >= 3; max_blindex--) {
  	if(zip_bl_tree[zip_bl_order[max_blindex]].dl != 0) break;
      }
      /* Update opt_len to include the bit length tree and counts */
      zip_opt_len += 3*(max_blindex+1) + 5+5+4;
  //    Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld",
  //	    encoder->opt_len, encoder->static_len));
  
      return max_blindex;
  }
  
  /* ==========================================================================
   * Send the header for a block using dynamic Huffman trees: the counts, the
   * lengths of the bit length codes, the literal tree and the distance tree.
   * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4.
   */
  function zip_send_all_trees(lcodes, dcodes, blcodes) { // number of codes for each tree
      var rank; // index in bl_order
  
  //    Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes");
  //    Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES,
  //	    "too many codes");
  //    Tracev((stderr, "\nbl counts: "));
      zip_send_bits(lcodes-257, 5); // not +255 as stated in appnote.txt
      zip_send_bits(dcodes-1,   5);
      zip_send_bits(blcodes-4,  4); // not -3 as stated in appnote.txt
      for(rank = 0; rank < blcodes; rank++) {
  //      Tracev((stderr, "\nbl code %2d ", bl_order[rank]));
  	zip_send_bits(zip_bl_tree[zip_bl_order[rank]].dl, 3);
      }
  
      // send the literal tree
      zip_send_tree(zip_dyn_ltree,lcodes-1);
  
      // send the distance tree
      zip_send_tree(zip_dyn_dtree,dcodes-1);
  }
  
  /* ==========================================================================
   * Determine the best encoding for the current block: dynamic trees, static
   * trees or store, and output the encoded block to the zip file.
   */
  function zip_flush_block(eof) { // true if this is the last block for a file
      var opt_lenb, static_lenb; // opt_len and static_len in bytes
      var max_blindex;	// index of last bit length code of non zero freq
      var stored_len;	// length of input block
  
      stored_len = zip_strstart - zip_block_start;
      zip_flag_buf[zip_last_flags] = zip_flags; // Save the flags for the last 8 items
  
      // Construct the literal and distance trees
      zip_build_tree(zip_l_desc);
  //    Tracev((stderr, "\nlit data: dyn %ld, stat %ld",
  //	    encoder->opt_len, encoder->static_len));
  
      zip_build_tree(zip_d_desc);
  //    Tracev((stderr, "\ndist data: dyn %ld, stat %ld",
  //	    encoder->opt_len, encoder->static_len));
      /* At this point, opt_len and static_len are the total bit lengths of
       * the compressed block data, excluding the tree representations.
       */
  
      /* Build the bit length tree for the above two trees, and get the index
       * in bl_order of the last bit length code to send.
       */
      max_blindex = zip_build_bl_tree();
  
      // Determine the best encoding. Compute first the block length in bytes
      opt_lenb	= (zip_opt_len   +3+7)>>3;
      static_lenb = (zip_static_len+3+7)>>3;
  
  //    Trace((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u dist %u ",
  //	   opt_lenb, encoder->opt_len,
  //	   static_lenb, encoder->static_len, stored_len,
  //	   encoder->last_lit, encoder->last_dist));
  
      if(static_lenb <= opt_lenb)
  	opt_lenb = static_lenb;
      if(stored_len + 4 <= opt_lenb // 4: two words for the lengths
         && zip_block_start >= 0) {
  	var i;
  
  	/* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE.
  	 * Otherwise we can't have processed more than WSIZE input bytes since
  	 * the last block flush, because compression would have been
  	 * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
  	 * transform a block into a stored block.
  	 */
  	zip_send_bits((zip_STORED_BLOCK<<1)+eof, 3);  /* send block type */
  	zip_bi_windup();		 /* align on byte boundary */
  	zip_put_short(stored_len);
  	zip_put_short(~stored_len);
  
        // copy block
  /*
        p = &window[block_start];
        for(i = 0; i < stored_len; i++)
  	put_byte(p[i]);
  */
  	for(i = 0; i < stored_len; i++)
  	    zip_put_byte(zip_window[zip_block_start + i]);
  
      } else if(static_lenb == opt_lenb) {
  	zip_send_bits((zip_STATIC_TREES<<1)+eof, 3);
  	zip_compress_block(zip_static_ltree, zip_static_dtree);
      } else {
  	zip_send_bits((zip_DYN_TREES<<1)+eof, 3);
  	zip_send_all_trees(zip_l_desc.max_code+1,
  			   zip_d_desc.max_code+1,
  			   max_blindex+1);
  	zip_compress_block(zip_dyn_ltree, zip_dyn_dtree);
      }
  
      zip_init_block();
  
      if(eof != 0)
  	zip_bi_windup();
  }
  
  /* ==========================================================================
   * Save the match info and tally the frequency counts. Return true if
   * the current block must be flushed.
   */
  function zip_ct_tally(
  	dist, // distance of matched string
  	lc) { // match length-MIN_MATCH or unmatched char (if dist==0)
      zip_l_buf[zip_last_lit++] = lc;
      if(dist == 0) {
  	// lc is the unmatched char
  	zip_dyn_ltree[lc].fc++;
      } else {
  	// Here, lc is the match length - MIN_MATCH
  	dist--;		    // dist = match distance - 1
  //      Assert((ush)dist < (ush)MAX_DIST &&
  //	     (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) &&
  //	     (ush)D_CODE(dist) < (ush)D_CODES,  "ct_tally: bad match");
  
  	zip_dyn_ltree[zip_length_code[lc]+zip_LITERALS+1].fc++;
  	zip_dyn_dtree[zip_D_CODE(dist)].fc++;
  
  	zip_d_buf[zip_last_dist++] = dist;
  	zip_flags |= zip_flag_bit;
      }
      zip_flag_bit <<= 1;
  
      // Output the flags if they fill a byte
      if((zip_last_lit & 7) == 0) {
  	zip_flag_buf[zip_last_flags++] = zip_flags;
  	zip_flags = 0;
  	zip_flag_bit = 1;
      }
      // Try to guess if it is profitable to stop the current block here
      if(zip_compr_level > 2 && (zip_last_lit & 0xfff) == 0) {
  	// Compute an upper bound for the compressed length
  	var out_length = zip_last_lit * 8;
  	var in_length = zip_strstart - zip_block_start;
  	var dcode;
  
  	for(dcode = 0; dcode < zip_D_CODES; dcode++) {
  	    out_length += zip_dyn_dtree[dcode].fc * (5 + zip_extra_dbits[dcode]);
  	}
  	out_length >>= 3;
  //      Trace((stderr,"\nlast_lit %u, last_dist %u, in %ld, out ~%ld(%ld%%) ",
  //	     encoder->last_lit, encoder->last_dist, in_length, out_length,
  //	     100L - out_length*100L/in_length));
  	if(zip_last_dist < parseInt(zip_last_lit/2) &&
  	   out_length < parseInt(in_length/2))
  	    return true;
      }
      return (zip_last_lit == zip_LIT_BUFSIZE-1 ||
  	    zip_last_dist == zip_DIST_BUFSIZE);
      /* We avoid equality with LIT_BUFSIZE because of wraparound at 64K
       * on 16 bit machines and because stored blocks are restricted to
       * 64K-1 bytes.
       */
  }
  
    /* ==========================================================================
     * Send the block data compressed using the given Huffman trees
     */
  function zip_compress_block(
  	ltree,	// literal tree
  	dtree) {	// distance tree
      var dist;		// distance of matched string
      var lc;		// match length or unmatched char (if dist == 0)
      var lx = 0;		// running index in l_buf
      var dx = 0;		// running index in d_buf
      var fx = 0;		// running index in flag_buf
      var flag = 0;	// current flags
      var code;		// the code to send
      var extra;		// number of extra bits to send
  
      if(zip_last_lit != 0) do {
  	if((lx & 7) == 0)
  	    flag = zip_flag_buf[fx++];
  	lc = zip_l_buf[lx++] & 0xff;
  	if((flag & 1) == 0) {
  	    zip_SEND_CODE(lc, ltree); /* send a literal byte */
  //	Tracecv(isgraph(lc), (stderr," '%c' ", lc));
  	} else {
  	    // Here, lc is the match length - MIN_MATCH
  	    code = zip_length_code[lc];
  	    zip_SEND_CODE(code+zip_LITERALS+1, ltree); // send the length code
  	    extra = zip_extra_lbits[code];
  	    if(extra != 0) {
  		lc -= zip_base_length[code];
  		zip_send_bits(lc, extra); // send the extra length bits
  	    }
  	    dist = zip_d_buf[dx++];
  	    // Here, dist is the match distance - 1
  	    code = zip_D_CODE(dist);
  //	Assert (code < D_CODES, "bad d_code");
  
  	    zip_SEND_CODE(code, dtree);	  // send the distance code
  	    extra = zip_extra_dbits[code];
  	    if(extra != 0) {
  		dist -= zip_base_dist[code];
  		zip_send_bits(dist, extra);   // send the extra distance bits
  	    }
  	} // literal or match pair ?
  	flag >>= 1;
      } while(lx < zip_last_lit);
  
      zip_SEND_CODE(zip_END_BLOCK, ltree);
  }
  
  /* ==========================================================================
   * Send a value on a given number of bits.
   * IN assertion: length <= 16 and value fits in length bits.
   */
  var zip_Buf_size = 16; // bit size of bi_buf
  function zip_send_bits(
  	value,	// value to send
  	length) {	// number of bits
      /* If not enough room in bi_buf, use (valid) bits from bi_buf and
       * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid))
       * unused bits in value.
       */
      if(zip_bi_valid > zip_Buf_size - length) {
  	zip_bi_buf |= (value << zip_bi_valid);
  	zip_put_short(zip_bi_buf);
  	zip_bi_buf = (value >> (zip_Buf_size - zip_bi_valid));
  	zip_bi_valid += length - zip_Buf_size;
      } else {
  	zip_bi_buf |= value << zip_bi_valid;
  	zip_bi_valid += length;
      }
  }
  
  /* ==========================================================================
   * Reverse the first len bits of a code, using straightforward code (a faster
   * method would use a table)
   * IN assertion: 1 <= len <= 15
   */
  function zip_bi_reverse(
  	code,	// the value to invert
  	len) {	// its bit length
      var res = 0;
      do {
  	res |= code & 1;
  	code >>= 1;
  	res <<= 1;
      } while(--len > 0);
      return res >> 1;
  }
  
  /* ==========================================================================
   * Write out any remaining bits in an incomplete byte.
   */
  function zip_bi_windup() {
      if(zip_bi_valid > 8) {
  	zip_put_short(zip_bi_buf);
      } else if(zip_bi_valid > 0) {
  	zip_put_byte(zip_bi_buf);
      }
      zip_bi_buf = 0;
      zip_bi_valid = 0;
  }
  
  function zip_qoutbuf() {
      if(zip_outcnt != 0) {
  	var q, i;
  	q = zip_new_queue();
  	if(zip_qhead == null)
  	    zip_qhead = zip_qtail = q;
  	else
  	    zip_qtail = zip_qtail.next = q;
  	q.len = zip_outcnt - zip_outoff;
  //      System.arraycopy(zip_outbuf, zip_outoff, q.ptr, 0, q.len);
  	for(i = 0; i < q.len; i++)
  	    q.ptr[i] = zip_outbuf[zip_outoff + i];
  	zip_outcnt = zip_outoff = 0;
      }
  }
  
  function zip_deflate(str, level) {
      var out, buff;
      var i, j;
  
      zip_deflate_data = str;
      zip_deflate_pos = 0;
      if(typeof level == "undefined")
  	level = zip_DEFAULT_LEVEL;
      zip_deflate_start(level);
  
      buff = new Array(1024);
      out = "";
      while((i = zip_deflate_internal(buff, 0, buff.length)) > 0) {
  	for(j = 0; j < i; j++)
  	    out += String.fromCharCode(buff[j]);
      }
      zip_deflate_data = null; // G.C.
      return out;
  }