sys/net/zlib.c

447                 /* used by trees.c: */
460     int heap[2*L_CODES+1];      /* heap used to build the Huffman trees */
464      * The same heap array is used to build all trees.
468     /* Depth of each subtree used as tie breaker for trees of equal frequency
484      *   - creating new Huffman trees less frequently may not provide fast
489      *     trees more frequently.
501     ulg opt_len;        /* bit length of current block with optimal trees */
502     ulg static_len;     /* bit length of current block with static trees */
538         /* in trees.c */
1845 /* +++ trees.c */
1846 /* trees.c -- output deflated data using Huffman coding
1854  *      The "deflation" process uses several Huffman trees. The more
1877 /* From: trees.c,v 1.11 1996/07/24 13:41:06 me Exp $ */
2181     /* Initialize the trees. */
2572     /* Determine the bit length frequencies for literal and distance trees */
2591     Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld",
2598  * Send the header for a block using dynamic Huffman trees: the counts, the
2688  * Determine the best encoding for the current block: dynamic trees, static
2689  * trees or store, and output the encoded block to the zip file. This function
2701     /* Build the Huffman trees unless a stored block is forced */
2707 	/* Construct the literal and distance trees */
2719 	/* Build the bit length tree for the above two trees, and get the index
2773     } else if (static_lenb >= 0) { /* force static trees */
2850  * Send the block data compressed using the given Huffman trees
2996 /* --- trees.c */
3547       DTREE,    /* get length, distance trees for a dynamic block */
3569     } trees;            /* if DTREE, decoding info for trees */
3572       inflate_huft *td;         /* trees to free */
3661       However, static trees define 32 codes (all 5 bits) to fill out the
3693     ZFREE(z, s->sub.trees.blens);
3837       s->sub.trees.table = t = (uInt)b & 0x3fff;
3850       if ((s->sub.trees.blens = (uIntf*)ZALLOC(z, t, sizeof(uInt))) == Z_NULL)
3856       s->sub.trees.index = 0;
3860       while (s->sub.trees.index < 4 + (s->sub.trees.table >> 10))
3863         s->sub.trees.blens[border[s->sub.trees.index++]] = (uInt)b & 7;
3866       while (s->sub.trees.index < 19)
3867         s->sub.trees.blens[border[s->sub.trees.index++]] = 0;
3868       s->sub.trees.bb = 7;
3869       t = inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb,
3870                              &s->sub.trees.tb, z);
3875           ZFREE(z, s->sub.trees.blens);
3880       s->sub.trees.index = 0;
3884       while (t = s->sub.trees.table,
3885              s->sub.trees.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f))
3890         t = s->sub.trees.bb;
3892         h = s->sub.trees.tb + ((uInt)b & inflate_mask[t]);
3898           s->sub.trees.blens[s->sub.trees.index++] = c;
3908           i = s->sub.trees.index;
3909           t = s->sub.trees.table;
3913             inflate_trees_free(s->sub.trees.tb, z);
3914             ZFREE(z, s->sub.trees.blens);
3920           c = c == 16 ? s->sub.trees.blens[i - 1] : 0;
3922             s->sub.trees.blens[i++] = c;
3924           s->sub.trees.index = i;
3927       inflate_trees_free(s->sub.trees.tb, z);
3928       s->sub.trees.tb = Z_NULL;
3936         t = s->sub.trees.table;
3941                                   s->sub.trees.blens, &bl, &bd, &tl, &td, z);
3945             ZFREE(z, s->sub.trees.blens);
3951         Tracev((stderr, "inflate:       trees ok, %d * %d bytes used\n",
3962 	 * sub.trees is union'd with sub.decode.
3964         ZFREE(z, s->sub.trees.blens);
4104 /* inftrees.c -- generate Huffman trees for efficient decoding