trees.c
Go to the documentation of this file.
1 /* trees.c -- output deflated data using Huffman coding
2  * Copyright (C) 1995-2005 Jean-loup Gailly
3  * For conditions of distribution and use, see copyright notice in zlib.h
4  */
5 
6 /*
7  * ALGORITHM
8  *
9  * The "deflation" process uses several Huffman trees. The more
10  * common source values are represented by shorter bit sequences.
11  *
12  * Each code tree is stored in a compressed form which is itself
13  * a Huffman encoding of the lengths of all the code strings (in
14  * ascending order by source values). The actual code strings are
15  * reconstructed from the lengths in the inflate process, as described
16  * in the deflate specification.
17  *
18  * REFERENCES
19  *
20  * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification".
21  * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc
22  *
23  * Storer, James A.
24  * Data Compression: Methods and Theory, pp. 49-50.
25  * Computer Science Press, 1988. ISBN 0-7167-8156-5.
26  *
27  * Sedgewick, R.
28  * Algorithms, p290.
29  * Addison-Wesley, 1983. ISBN 0-201-06672-6.
30  */
31 
32 /* @(#) $Id$ */
33 
34 /* #define GEN_TREES_H */
35 
36 #include "deflate.h"
37 
38 #ifdef DEBUG
39 # include <ctype.h>
40 #endif
41 
42 /* ===========================================================================
43  * Constants
44  */
45 
46 #define MAX_BL_BITS 7
47 /* Bit length codes must not exceed MAX_BL_BITS bits */
48 
49 #define END_BLOCK 256
50 /* end of block literal code */
51 
52 #define REP_3_6 16
53 /* repeat previous bit length 3-6 times (2 bits of repeat count) */
54 
55 #define REPZ_3_10 17
56 /* repeat a zero length 3-10 times (3 bits of repeat count) */
57 
58 #define REPZ_11_138 18
59 /* repeat a zero length 11-138 times (7 bits of repeat count) */
60 
61 local const int extra_lbits[LENGTH_CODES] /* extra bits for each length code */
62  = {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};
63 
64 local const int extra_dbits[D_CODES] /* extra bits for each distance code */
65  = {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};
66 
67 local const int extra_blbits[BL_CODES]/* extra bits for each bit length code */
68  = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7};
69 
71  = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15};
72 /* The lengths of the bit length codes are sent in order of decreasing
73  * probability, to avoid transmitting the lengths for unused bit length codes.
74  */
75 
76 #define Buf_size (8 * 2*sizeof(char))
77 /* Number of bits used within bi_buf. (bi_buf might be implemented on
78  * more than 16 bits on some systems.)
79  */
80 
81 /* ===========================================================================
82  * Local data. These are initialized only once.
83  */
84 
85 #define DIST_CODE_LEN 512 /* see definition of array dist_code below */
86 
87 #if defined(GEN_TREES_H) || !defined(STDC)
88 /* non ANSI compilers may not accept trees.h */
89 
91 /* The static literal tree. Since the bit lengths are imposed, there is no
92  * need for the L_CODES extra codes used during heap construction. However
93  * The codes 286 and 287 are needed to build a canonical tree (see _tr_init
94  * below).
95  */
96 
98 /* The static distance tree. (Actually a trivial tree since all codes use
99  * 5 bits.)
100  */
101 
103 /* Distance codes. The first 256 values correspond to the distances
104  * 3 .. 258, the last 256 values correspond to the top 8 bits of
105  * the 15 bit distances.
106  */
107 
109 /* length code for each normalized match length (0 == MIN_MATCH) */
110 
112 /* First normalized length for each code (0 = MIN_MATCH) */
113 
115 /* First normalized distance for each code (0 = distance of 1) */
116 
117 #else
118 # include "trees.h"
119 #endif /* GEN_TREES_H */
120 
121 struct static_tree_desc_s {
122  const ct_data *static_tree; /* static tree or NULL */
123  const intf *extra_bits; /* extra bits for each code or NULL */
124  int extra_base; /* base index for extra_bits */
125  int elems; /* max number of elements in the tree */
126  int max_length; /* max bit length for the codes */
127 };
128 
131 
134 
136 {(const ct_data *)0, extra_blbits, 0, BL_CODES, MAX_BL_BITS};
137 
138 /* ===========================================================================
139  * Local (static) routines in this file.
140  */
141 
142 local void tr_static_init OF((void));
143 local void init_block OF((deflate_state *s));
144 local void pqdownheap OF((deflate_state *s, ct_data *tree, int k));
145 local void gen_bitlen OF((deflate_state *s, tree_desc *desc));
146 local void gen_codes OF((ct_data *tree, int max_code, ushf *bl_count));
147 local void build_tree OF((deflate_state *s, tree_desc *desc));
148 local void scan_tree OF((deflate_state *s, ct_data *tree, int max_code));
149 local void send_tree OF((deflate_state *s, ct_data *tree, int max_code));
151 local void send_all_trees OF((deflate_state *s, int lcodes, int dcodes,
152  int blcodes));
153 local void compress_block OF((deflate_state *s, ct_data *ltree,
154  ct_data *dtree));
156 local unsigned bi_reverse OF((unsigned value, int length));
157 local void bi_windup OF((deflate_state *s));
158 local void bi_flush OF((deflate_state *s));
159 local void copy_block OF((deflate_state *s, charf *buf, unsigned len,
160  int header));
161 
162 #ifdef GEN_TREES_H
163 local void gen_trees_header OF((void));
164 #endif
165 
166 #ifndef DEBUG
167 # define send_code(s, c, tree) send_bits(s, tree[c].Code, tree[c].Len)
168  /* Send a code of the given tree. c and tree must not have side effects */
169 
170 #else /* DEBUG */
171 # define send_code(s, c, tree) \
172  { if (z_verbose>2) fprintf(stderr,"\ncd %3d ",(c)); \
173  send_bits(s, tree[c].Code, tree[c].Len); }
174 #endif
175 
176 /* ===========================================================================
177  * Output a short LSB first on the stream.
178  * IN assertion: there is enough room in pendingBuf.
179  */
180 #define put_short(s, w) { \
181  put_byte(s, (uch)((w) & 0xff)); \
182  put_byte(s, (uch)((ush)(w) >> 8)); \
183 }
184 
185 /* ===========================================================================
186  * Send a value on a given number of bits.
187  * IN assertion: length <= 16 and value fits in length bits.
188  */
189 #ifdef DEBUG
190 local void send_bits OF((deflate_state *s, int value, int length));
191 
192 local void send_bits(s, value, length)
193  deflate_state *s;
194  int value; /* value to send */
195  int length; /* number of bits */
196 {
197  Tracevv((stderr," l %2d v %4x ", length, value));
198  Assert(length > 0 && length <= 15, "invalid length");
199  s->bits_sent += (ulg)length;
200 
201  /* If not enough room in bi_buf, use (valid) bits from bi_buf and
202  * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid))
203  * unused bits in value.
204  */
205  if (s->bi_valid > (int)Buf_size - length) {
206  s->bi_buf |= (value << s->bi_valid);
207  put_short(s, s->bi_buf);
208  s->bi_buf = (ush)value >> (Buf_size - s->bi_valid);
209  s->bi_valid += length - Buf_size;
210  } else {
211  s->bi_buf |= value << s->bi_valid;
212  s->bi_valid += length;
213  }
214 }
215 #else /* !DEBUG */
216 
217 #define send_bits(s, value, length) \
218 { int len = length;\
219  if (s->bi_valid > (int)Buf_size - len) {\
220  int val = value;\
221  s->bi_buf |= (val << s->bi_valid);\
222  put_short(s, s->bi_buf);\
223  s->bi_buf = (ush)val >> (Buf_size - s->bi_valid);\
224  s->bi_valid += len - Buf_size;\
225  } else {\
226  s->bi_buf |= (value) << s->bi_valid;\
227  s->bi_valid += len;\
228  }\
229 }
230 #endif /* DEBUG */
231 
232 
233 /* the arguments must not have side effects */
234 
235 /* ===========================================================================
236  * Initialize the various 'constant' tables.
237  */
239 {
240 #if defined(GEN_TREES_H) || !defined(STDC)
241  static int static_init_done = 0;
242  int n; /* iterates over tree elements */
243  int bits; /* bit counter */
244  int length; /* length value */
245  int code; /* code value */
246  int dist; /* distance index */
247  ush bl_count[MAX_BITS+1];
248  /* number of codes at each bit length for an optimal tree */
249 
250  if (static_init_done) return;
251 
252  /* For some embedded targets, global variables are not initialized: */
258 
259  /* Initialize the mapping length (0..255) -> length code (0..28) */
260  length = 0;
261  for (code = 0; code < LENGTH_CODES-1; code++) {
263  for (n = 0; n < (1<<extra_lbits[code]); n++) {
264  _length_code[length++] = (uch)code;
265  }
266  }
267  Assert (length == 256, "tr_static_init: length != 256");
268  /* Note that the length 255 (match length 258) can be represented
269  * in two different ways: code 284 + 5 bits or code 285, so we
270  * overwrite length_code[255] to use the best encoding:
271  */
272  _length_code[length-1] = (uch)code;
273 
274  /* Initialize the mapping dist (0..32K) -> dist code (0..29) */
275  dist = 0;
276  for (code = 0 ; code < 16; code++) {
277  base_dist[code] = dist;
278  for (n = 0; n < (1<<extra_dbits[code]); n++) {
279  _dist_code[dist++] = (uch)code;
280  }
281  }
282  Assert (dist == 256, "tr_static_init: dist != 256");
283  dist >>= 7; /* from now on, all distances are divided by 128 */
284  for ( ; code < D_CODES; code++) {
285  base_dist[code] = dist << 7;
286  for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) {
287  _dist_code[256 + dist++] = (uch)code;
288  }
289  }
290  Assert (dist == 256, "tr_static_init: 256+dist != 512");
291 
292  /* Construct the codes of the static literal tree */
293  for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0;
294  n = 0;
295  while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++;
296  while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++;
297  while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++;
298  while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++;
299  /* Codes 286 and 287 do not exist, but we must include them in the
300  * tree construction to get a canonical Huffman tree (longest code
301  * all ones)
302  */
303  gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count);
304 
305  /* The static distance tree is trivial: */
306  for (n = 0; n < D_CODES; n++) {
307  static_dtree[n].Len = 5;
308  static_dtree[n].Code = bi_reverse((unsigned)n, 5);
309  }
310  static_init_done = 1;
311 
312 # ifdef GEN_TREES_H
313  gen_trees_header();
314 # endif
315 #endif /* defined(GEN_TREES_H) || !defined(STDC) */
316 }
317 
318 /* ===========================================================================
319  * Genererate the file trees.h describing the static trees.
320  */
321 #ifdef GEN_TREES_H
322 # ifndef DEBUG
323 # include <stdio.h>
324 # endif
325 
326 # define SEPARATOR(i, last, width) \
327  ((i) == (last)? "\n};\n\n" : \
328  ((i) % (width) == (width)-1 ? ",\n" : ", "))
329 
330 void gen_trees_header()
331 {
332  FILE *header = fopen("trees.h", "w");
333  int i;
334 
335  Assert (header != NULL, "Can't open trees.h");
336  fprintf(header,
337  "/* header created automatically with -DGEN_TREES_H */\n\n");
338 
339  fprintf(header, "local const ct_data static_ltree[L_CODES+2] = {\n");
340  for (i = 0; i < L_CODES+2; i++) {
341  fprintf(header, "{{%3u},{%3u}}%s", static_ltree[i].Code,
342  static_ltree[i].Len, SEPARATOR(i, L_CODES+1, 5));
343  }
344 
345  fprintf(header, "local const ct_data static_dtree[D_CODES] = {\n");
346  for (i = 0; i < D_CODES; i++) {
347  fprintf(header, "{{%2u},{%2u}}%s", static_dtree[i].Code,
348  static_dtree[i].Len, SEPARATOR(i, D_CODES-1, 5));
349  }
350 
351  fprintf(header, "const uch _dist_code[DIST_CODE_LEN] = {\n");
352  for (i = 0; i < DIST_CODE_LEN; i++) {
353  fprintf(header, "%2u%s", _dist_code[i],
354  SEPARATOR(i, DIST_CODE_LEN-1, 20));
355  }
356 
357  fprintf(header, "const uch _length_code[MAX_MATCH-MIN_MATCH+1]= {\n");
358  for (i = 0; i < MAX_MATCH-MIN_MATCH+1; i++) {
359  fprintf(header, "%2u%s", _length_code[i],
360  SEPARATOR(i, MAX_MATCH-MIN_MATCH, 20));
361  }
362 
363  fprintf(header, "local const int base_length[LENGTH_CODES] = {\n");
364  for (i = 0; i < LENGTH_CODES; i++) {
365  fprintf(header, "%1u%s", base_length[i],
366  SEPARATOR(i, LENGTH_CODES-1, 20));
367  }
368 
369  fprintf(header, "local const int base_dist[D_CODES] = {\n");
370  for (i = 0; i < D_CODES; i++) {
371  fprintf(header, "%5u%s", base_dist[i],
372  SEPARATOR(i, D_CODES-1, 10));
373  }
374 
375  fclose(header);
376 }
377 #endif /* GEN_TREES_H */
378 
379 /* ===========================================================================
380  * Initialize the tree data structures for a new zlib stream.
381  */
382 void _tr_init(s)
383  deflate_state *s;
384 {
385  tr_static_init();
386 
387  s->l_desc.dyn_tree = s->dyn_ltree;
388  s->l_desc.stat_desc = &static_l_desc;
389 
390  s->d_desc.dyn_tree = s->dyn_dtree;
391  s->d_desc.stat_desc = &static_d_desc;
392 
393  s->bl_desc.dyn_tree = s->bl_tree;
394  s->bl_desc.stat_desc = &static_bl_desc;
395 
396  s->bi_buf = 0;
397  s->bi_valid = 0;
398  s->last_eob_len = 8; /* enough lookahead for inflate */
399 #ifdef DEBUG
400  s->compressed_len = 0L;
401  s->bits_sent = 0L;
402 #endif
403 
404  /* Initialize the first block of the first file: */
405  init_block(s);
406 }
407 
408 /* ===========================================================================
409  * Initialize a new block.
410  */
412  deflate_state *s;
413 {
414  int n; /* iterates over tree elements */
415 
416  /* Initialize the trees. */
417  for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0;
418  for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0;
419  for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0;
420 
421  s->dyn_ltree[END_BLOCK].Freq = 1;
422  s->opt_len = s->static_len = 0L;
423  s->last_lit = s->matches = 0;
424 }
425 
426 #define SMALLEST 1
427 /* Index within the heap array of least frequent node in the Huffman tree */
428 
429 
430 /* ===========================================================================
431  * Remove the smallest element from the heap and recreate the heap with
432  * one less element. Updates heap and heap_len.
433  */
434 #define pqremove(s, tree, top) \
435 {\
436  top = s->heap[SMALLEST]; \
437  s->heap[SMALLEST] = s->heap[s->heap_len--]; \
438  pqdownheap(s, tree, SMALLEST); \
439 }
440 
441 /* ===========================================================================
442  * Compares to subtrees, using the tree depth as tie breaker when
443  * the subtrees have equal frequency. This minimizes the worst case length.
444  */
445 #define smaller(tree, n, m, depth) \
446  (tree[n].Freq < tree[m].Freq || \
447  (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m]))
448 
449 /* ===========================================================================
450  * Restore the heap property by moving down the tree starting at node k,
451  * exchanging a node with the smallest of its two sons if necessary, stopping
452  * when the heap property is re-established (each father smaller than its
453  * two sons).
454  */
455 local void pqdownheap(s, tree, k)
456  deflate_state *s;
457  ct_data *tree; /* the tree to restore */
458  int k; /* node to move down */
459 {
460  int v = s->heap[k];
461  int j = k << 1; /* left son of k */
462  while (j <= s->heap_len) {
463  /* Set j to the smallest of the two sons: */
464  if (j < s->heap_len &&
465  smaller(tree, s->heap[j+1], s->heap[j], s->depth)) {
466  j++;
467  }
468  /* Exit if v is smaller than both sons */
469  if (smaller(tree, v, s->heap[j], s->depth)) break;
470 
471  /* Exchange v with the smallest son */
472  s->heap[k] = s->heap[j]; k = j;
473 
474  /* And continue down the tree, setting j to the left son of k */
475  j <<= 1;
476  }
477  s->heap[k] = v;
478 }
479 
480 /* ===========================================================================
481  * Compute the optimal bit lengths for a tree and update the total bit length
482  * for the current block.
483  * IN assertion: the fields freq and dad are set, heap[heap_max] and
484  * above are the tree nodes sorted by increasing frequency.
485  * OUT assertions: the field len is set to the optimal bit length, the
486  * array bl_count contains the frequencies for each bit length.
487  * The length opt_len is updated; static_len is also updated if stree is
488  * not null.
489  */
490 local void gen_bitlen(s, desc)
491  deflate_state *s;
492  tree_desc *desc; /* the tree descriptor */
493 {
494  ct_data *tree = desc->dyn_tree;
495  int max_code = desc->max_code;
496  const ct_data *stree = desc->stat_desc->static_tree;
497  const intf *extra = desc->stat_desc->extra_bits;
498  int base = desc->stat_desc->extra_base;
499  int max_length = desc->stat_desc->max_length;
500  int h; /* heap index */
501  int n, m; /* iterate over the tree elements */
502  int bits; /* bit length */
503  int xbits; /* extra bits */
504  ush f; /* frequency */
505  int overflow = 0; /* number of elements with bit length too large */
506 
507  for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0;
508 
509  /* In a first pass, compute the optimal bit lengths (which may
510  * overflow in the case of the bit length tree).
511  */
512  tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */
513 
514  for (h = s->heap_max+1; h < HEAP_SIZE; h++) {
515  n = s->heap[h];
516  bits = tree[tree[n].Dad].Len + 1;
517  if (bits > max_length) bits = max_length, overflow++;
518  tree[n].Len = (ush)bits;
519  /* We overwrite tree[n].Dad which is no longer needed */
520 
521  if (n > max_code) continue; /* not a leaf node */
522 
523  s->bl_count[bits]++;
524  xbits = 0;
525  if (n >= base) xbits = extra[n-base];
526  f = tree[n].Freq;
527  s->opt_len += (ulg)f * (bits + xbits);
528  if (stree) s->static_len += (ulg)f * (stree[n].Len + xbits);
529  }
530  if (overflow == 0) return;
531 
532  Trace((stderr,"\nbit length overflow\n"));
533  /* This happens for example on obj2 and pic of the Calgary corpus */
534 
535  /* Find the first bit length which could increase: */
536  do {
537  bits = max_length-1;
538  while (s->bl_count[bits] == 0) bits--;
539  s->bl_count[bits]--; /* move one leaf down the tree */
540  s->bl_count[bits+1] += 2; /* move one overflow item as its brother */
541  s->bl_count[max_length]--;
542  /* The brother of the overflow item also moves one step up,
543  * but this does not affect bl_count[max_length]
544  */
545  overflow -= 2;
546  } while (overflow > 0);
547 
548  /* Now recompute all bit lengths, scanning in increasing frequency.
549  * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all
550  * lengths instead of fixing only the wrong ones. This idea is taken
551  * from 'ar' written by Haruhiko Okumura.)
552  */
553  for (bits = max_length; bits != 0; bits--) {
554  n = s->bl_count[bits];
555  while (n != 0) {
556  m = s->heap[--h];
557  if (m > max_code) continue;
558  if ((unsigned) tree[m].Len != (unsigned) bits) {
559  Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits));
560  s->opt_len += ((long)bits - (long)tree[m].Len)
561  *(long)tree[m].Freq;
562  tree[m].Len = (ush)bits;
563  }
564  n--;
565  }
566  }
567 }
568 
569 /* ===========================================================================
570  * Generate the codes for a given tree and bit counts (which need not be
571  * optimal).
572  * IN assertion: the array bl_count contains the bit length statistics for
573  * the given tree and the field len is set for all tree elements.
574  * OUT assertion: the field code is set for all tree elements of non
575  * zero code length.
576  */
577 local void gen_codes (tree, max_code, bl_count)
578  ct_data *tree; /* the tree to decorate */
579  int max_code; /* largest code with non zero frequency */
580  ushf *bl_count; /* number of codes at each bit length */
581 {
582  ush next_code[MAX_BITS+1]; /* next code value for each bit length */
583  ush code = 0; /* running code value */
584  int bits; /* bit index */
585  int n; /* code index */
586 
587  /* The distribution counts are first used to generate the code values
588  * without bit reversal.
589  */
590  for (bits = 1; bits <= MAX_BITS; bits++) {
591  next_code[bits] = code = (code + bl_count[bits-1]) << 1;
592  }
593  /* Check that the bit counts in bl_count are consistent. The last code
594  * must be all ones.
595  */
596  Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1,
597  "inconsistent bit counts");
598  Tracev((stderr,"\ngen_codes: max_code %d ", max_code));
599 
600  for (n = 0; n <= max_code; n++) {
601  int len = tree[n].Len;
602  if (len == 0) continue;
603  /* Now reverse the bits */
604  tree[n].Code = bi_reverse(next_code[len]++, len);
605 
606  Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
607  n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1));
608  }
609 }
610 
611 /* ===========================================================================
612  * Construct one Huffman tree and assigns the code bit strings and lengths.
613  * Update the total bit length for the current block.
614  * IN assertion: the field freq is set for all tree elements.
615  * OUT assertions: the fields len and code are set to the optimal bit length
616  * and corresponding code. The length opt_len is updated; static_len is
617  * also updated if stree is not null. The field max_code is set.
618  */
619 local void build_tree(s, desc)
620  deflate_state *s;
621  tree_desc *desc; /* the tree descriptor */
622 {
623  ct_data *tree = desc->dyn_tree;
624  const ct_data *stree = desc->stat_desc->static_tree;
625  int elems = desc->stat_desc->elems;
626  int n, m; /* iterate over heap elements */
627  int max_code = -1; /* largest code with non zero frequency */
628  int node; /* new node being created */
629 
630  /* Construct the initial heap, with least frequent element in
631  * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1].
632  * heap[0] is not used.
633  */
634  s->heap_len = 0, s->heap_max = HEAP_SIZE;
635 
636  for (n = 0; n < elems; n++) {
637  if (tree[n].Freq != 0) {
638  s->heap[++(s->heap_len)] = max_code = n;
639  s->depth[n] = 0;
640  } else {
641  tree[n].Len = 0;
642  }
643  }
644 
645  /* The pkzip format requires that at least one distance code exists,
646  * and that at least one bit should be sent even if there is only one
647  * possible code. So to avoid special checks later on we force at least
648  * two codes of non zero frequency.
649  */
650  while (s->heap_len < 2) {
651  node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0);
652  tree[node].Freq = 1;
653  s->depth[node] = 0;
654  s->opt_len--; if (stree) s->static_len -= stree[node].Len;
655  /* node is 0 or 1 so it does not have extra bits */
656  }
657  desc->max_code = max_code;
658 
659  /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,
660  * establish sub-heaps of increasing lengths:
661  */
662  for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n);
663 
664  /* Construct the Huffman tree by repeatedly combining the least two
665  * frequent nodes.
666  */
667  node = elems; /* next internal node of the tree */
668  do {
669  pqremove(s, tree, n); /* n = node of least frequency */
670  m = s->heap[SMALLEST]; /* m = node of next least frequency */
671 
672  s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */
673  s->heap[--(s->heap_max)] = m;
674 
675  /* Create a new node father of n and m */
676  tree[node].Freq = tree[n].Freq + tree[m].Freq;
677  s->depth[node] = (uch)((s->depth[n] >= s->depth[m] ?
678  s->depth[n] : s->depth[m]) + 1);
679  tree[n].Dad = tree[m].Dad = (ush)node;
680 #ifdef DUMP_BL_TREE
681  if (tree == s->bl_tree) {
682  fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)",
683  node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq);
684  }
685 #endif
686  /* and insert the new node in the heap */
687  s->heap[SMALLEST] = node++;
688  pqdownheap(s, tree, SMALLEST);
689 
690  } while (s->heap_len >= 2);
691 
692  s->heap[--(s->heap_max)] = s->heap[SMALLEST];
693 
694  /* At this point, the fields freq and dad are set. We can now
695  * generate the bit lengths.
696  */
697  gen_bitlen(s, (tree_desc *)desc);
698 
699  /* The field len is now set, we can generate the bit codes */
700  gen_codes ((ct_data *)tree, max_code, s->bl_count);
701 }
702 
703 /* ===========================================================================
704  * Scan a literal or distance tree to determine the frequencies of the codes
705  * in the bit length tree.
706  */
707 local void scan_tree (s, tree, max_code)
708  deflate_state *s;
709  ct_data *tree; /* the tree to be scanned */
710  int max_code; /* and its largest code of non zero frequency */
711 {
712  int n; /* iterates over all tree elements */
713  int prevlen = -1; /* last emitted length */
714  int curlen; /* length of current code */
715  int nextlen = tree[0].Len; /* length of next code */
716  int count = 0; /* repeat count of the current code */
717  int max_count = 7; /* max repeat count */
718  int min_count = 4; /* min repeat count */
719 
720  if (nextlen == 0) max_count = 138, min_count = 3;
721  tree[max_code+1].Len = (ush)0xffff; /* guard */
722 
723  for (n = 0; n <= max_code; n++) {
724  curlen = nextlen; nextlen = tree[n+1].Len;
725  if (++count < max_count && curlen == nextlen) {
726  continue;
727  } else if (count < min_count) {
728  s->bl_tree[curlen].Freq += count;
729  } else if (curlen != 0) {
730  if (curlen != prevlen) s->bl_tree[curlen].Freq++;
731  s->bl_tree[REP_3_6].Freq++;
732  } else if (count <= 10) {
733  s->bl_tree[REPZ_3_10].Freq++;
734  } else {
735  s->bl_tree[REPZ_11_138].Freq++;
736  }
737  count = 0; prevlen = curlen;
738  if (nextlen == 0) {
739  max_count = 138, min_count = 3;
740  } else if (curlen == nextlen) {
741  max_count = 6, min_count = 3;
742  } else {
743  max_count = 7, min_count = 4;
744  }
745  }
746 }
747 
748 /* ===========================================================================
749  * Send a literal or distance tree in compressed form, using the codes in
750  * bl_tree.
751  */
752 local void send_tree (s, tree, max_code)
753  deflate_state *s;
754  ct_data *tree; /* the tree to be scanned */
755  int max_code; /* and its largest code of non zero frequency */
756 {
757  int n; /* iterates over all tree elements */
758  int prevlen = -1; /* last emitted length */
759  int curlen; /* length of current code */
760  int nextlen = tree[0].Len; /* length of next code */
761  int count = 0; /* repeat count of the current code */
762  int max_count = 7; /* max repeat count */
763  int min_count = 4; /* min repeat count */
764 
765  /* tree[max_code+1].Len = -1; */ /* guard already set */
766  if (nextlen == 0) max_count = 138, min_count = 3;
767 
768  for (n = 0; n <= max_code; n++) {
769  curlen = nextlen; nextlen = tree[n+1].Len;
770  if (++count < max_count && curlen == nextlen) {
771  continue;
772  } else if (count < min_count) {
773  do { send_code(s, curlen, s->bl_tree); } while (--count != 0);
774 
775  } else if (curlen != 0) {
776  if (curlen != prevlen) {
777  send_code(s, curlen, s->bl_tree); count--;
778  }
779  Assert(count >= 3 && count <= 6, " 3_6?");
780  send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2);
781 
782  } else if (count <= 10) {
783  send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3);
784 
785  } else {
786  send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7);
787  }
788  count = 0; prevlen = curlen;
789  if (nextlen == 0) {
790  max_count = 138, min_count = 3;
791  } else if (curlen == nextlen) {
792  max_count = 6, min_count = 3;
793  } else {
794  max_count = 7, min_count = 4;
795  }
796  }
797 }
798 
799 /* ===========================================================================
800  * Construct the Huffman tree for the bit lengths and return the index in
801  * bl_order of the last bit length code to send.
802  */
804  deflate_state *s;
805 {
806  int max_blindex; /* index of last bit length code of non zero freq */
807 
808  /* Determine the bit length frequencies for literal and distance trees */
809  scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code);
810  scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code);
811 
812  /* Build the bit length tree: */
813  build_tree(s, (tree_desc *)(&(s->bl_desc)));
814  /* opt_len now includes the length of the tree representations, except
815  * the lengths of the bit lengths codes and the 5+5+4 bits for the counts.
816  */
817 
818  /* Determine the number of bit length codes to send. The pkzip format
819  * requires that at least 4 bit length codes be sent. (appnote.txt says
820  * 3 but the actual value used is 4.)
821  */
822  for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) {
823  if (s->bl_tree[bl_order[max_blindex]].Len != 0) break;
824  }
825  /* Update opt_len to include the bit length tree and counts */
826  s->opt_len += 3*(max_blindex+1) + 5+5+4;
827  Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld",
828  s->opt_len, s->static_len));
829 
830  return max_blindex;
831 }
832 
833 /* ===========================================================================
834  * Send the header for a block using dynamic Huffman trees: the counts, the
835  * lengths of the bit length codes, the literal tree and the distance tree.
836  * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4.
837  */
838 local void send_all_trees(s, lcodes, dcodes, blcodes)
839  deflate_state *s;
840  int lcodes, dcodes, blcodes; /* number of codes for each tree */
841 {
842  int rank; /* index in bl_order */
843 
844  Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes");
845  Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES,
846  "too many codes");
847  Tracev((stderr, "\nbl counts: "));
848  send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */
849  send_bits(s, dcodes-1, 5);
850  send_bits(s, blcodes-4, 4); /* not -3 as stated in appnote.txt */
851  for (rank = 0; rank < blcodes; rank++) {
852  Tracev((stderr, "\nbl code %2d ", bl_order[rank]));
853  send_bits(s, s->bl_tree[bl_order[rank]].Len, 3);
854  }
855  Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent));
856 
857  send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */
858  Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent));
859 
860  send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */
861  Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent));
862 }
863 
864 /* ===========================================================================
865  * Send a stored block
866  */
867 void _tr_stored_block(s, buf, stored_len, eof)
868  deflate_state *s;
869  charf *buf; /* input block */
870  ulg stored_len; /* length of input block */
871  int eof; /* true if this is the last block for a file */
872 {
873  send_bits(s, (STORED_BLOCK<<1)+eof, 3); /* send block type */
874 #ifdef DEBUG
875  s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L;
876  s->compressed_len += (stored_len + 4) << 3;
877 #endif
878  copy_block(s, buf, (unsigned)stored_len, 1); /* with header */
879 }
880 
881 /* ===========================================================================
882  * Send one empty static block to give enough lookahead for inflate.
883  * This takes 10 bits, of which 7 may remain in the bit buffer.
884  * The current inflate code requires 9 bits of lookahead. If the
885  * last two codes for the previous block (real code plus EOB) were coded
886  * on 5 bits or less, inflate may have only 5+3 bits of lookahead to decode
887  * the last real code. In this case we send two empty static blocks instead
888  * of one. (There are no problems if the previous block is stored or fixed.)
889  * To simplify the code, we assume the worst case of last real code encoded
890  * on one bit only.
891  */
892 void _tr_align(s)
893  deflate_state *s;
894 {
895  send_bits(s, STATIC_TREES<<1, 3);
897 #ifdef DEBUG
898  s->compressed_len += 10L; /* 3 for block type, 7 for EOB */
899 #endif
900  bi_flush(s);
901  /* Of the 10 bits for the empty block, we have already sent
902  * (10 - bi_valid) bits. The lookahead for the last real code (before
903  * the EOB of the previous block) was thus at least one plus the length
904  * of the EOB plus what we have just sent of the empty static block.
905  */
906  if (1 + s->last_eob_len + 10 - s->bi_valid < 9) {
907  send_bits(s, STATIC_TREES<<1, 3);
909 #ifdef DEBUG
910  s->compressed_len += 10L;
911 #endif
912  bi_flush(s);
913  }
914  s->last_eob_len = 7;
915 }
916 
917 /* ===========================================================================
918  * Determine the best encoding for the current block: dynamic trees, static
919  * trees or store, and output the encoded block to the zip file.
920  */
921 void _tr_flush_block(s, buf, stored_len, eof)
922  deflate_state *s;
923  charf *buf; /* input block, or NULL if too old */
924  ulg stored_len; /* length of input block */
925  int eof; /* true if this is the last block for a file */
926 {
927  ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */
928  int max_blindex = 0; /* index of last bit length code of non zero freq */
929 
930  /* Build the Huffman trees unless a stored block is forced */
931  if (s->level > 0) {
932 
933  /* Check if the file is binary or text */
934  if (stored_len > 0 && s->strm->data_type == Z_UNKNOWN)
935  set_data_type(s);
936 
937  /* Construct the literal and distance trees */
938  build_tree(s, (tree_desc *)(&(s->l_desc)));
939  Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len,
940  s->static_len));
941 
942  build_tree(s, (tree_desc *)(&(s->d_desc)));
943  Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len,
944  s->static_len));
945  /* At this point, opt_len and static_len are the total bit lengths of
946  * the compressed block data, excluding the tree representations.
947  */
948 
949  /* Build the bit length tree for the above two trees, and get the index
950  * in bl_order of the last bit length code to send.
951  */
952  max_blindex = build_bl_tree(s);
953 
954  /* Determine the best encoding. Compute the block lengths in bytes. */
955  opt_lenb = (s->opt_len+3+7)>>3;
956  static_lenb = (s->static_len+3+7)>>3;
957 
958  Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ",
959  opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len,
960  s->last_lit));
961 
962  if (static_lenb <= opt_lenb) opt_lenb = static_lenb;
963 
964  } else {
965  Assert(buf != (char*)0, "lost buf");
966  opt_lenb = static_lenb = stored_len + 5; /* force a stored block */
967  }
968 
969 #ifdef FORCE_STORED
970  if (buf != (char*)0) { /* force stored block */
971 #else
972  if (stored_len+4 <= opt_lenb && buf != (char*)0) {
973  /* 4: two words for the lengths */
974 #endif
975  /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE.
976  * Otherwise we can't have processed more than WSIZE input bytes since
977  * the last block flush, because compression would have been
978  * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
979  * transform a block into a stored block.
980  */
981  _tr_stored_block(s, buf, stored_len, eof);
982 
983 #ifdef FORCE_STATIC
984  } else if (static_lenb >= 0) { /* force static trees */
985 #else
986  } else if (s->strategy == Z_FIXED || static_lenb == opt_lenb) {
987 #endif
988  send_bits(s, (STATIC_TREES<<1)+eof, 3);
990 #ifdef DEBUG
991  s->compressed_len += 3 + s->static_len;
992 #endif
993  } else {
994  send_bits(s, (DYN_TREES<<1)+eof, 3);
995  send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1,
996  max_blindex+1);
997  compress_block(s, (ct_data *)s->dyn_ltree, (ct_data *)s->dyn_dtree);
998 #ifdef DEBUG
999  s->compressed_len += 3 + s->opt_len;
1000 #endif
1001  }
1002  Assert (s->compressed_len == s->bits_sent, "bad compressed size");
1003  /* The above check is made mod 2^32, for files larger than 512 MB
1004  * and uLong implemented on 32 bits.
1005  */
1006  init_block(s);
1007 
1008  if (eof) {
1009  bi_windup(s);
1010 #ifdef DEBUG
1011  s->compressed_len += 7; /* align on byte boundary */
1012 #endif
1013  }
1014  Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3,
1015  s->compressed_len-7*eof));
1016 }
1017 
1018 /* ===========================================================================
1019  * Save the match info and tally the frequency counts. Return true if
1020  * the current block must be flushed.
1021  */
1022 int _tr_tally (s, dist, lc)
1023  deflate_state *s;
1024  unsigned dist; /* distance of matched string */
1025  unsigned lc; /* match length-MIN_MATCH or unmatched char (if dist==0) */
1026 {
1027  s->d_buf[s->last_lit] = (ush)dist;
1028  s->l_buf[s->last_lit++] = (uch)lc;
1029  if (dist == 0) {
1030  /* lc is the unmatched char */
1031  s->dyn_ltree[lc].Freq++;
1032  } else {
1033  s->matches++;
1034  /* Here, lc is the match length - MIN_MATCH */
1035  dist--; /* dist = match distance - 1 */
1036  Assert((ush)dist < (ush)MAX_DIST(s) &&
1037  (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) &&
1038  (ush)d_code(dist) < (ush)D_CODES, "_tr_tally: bad match");
1039 
1040  s->dyn_ltree[_length_code[lc]+LITERALS+1].Freq++;
1041  s->dyn_dtree[d_code(dist)].Freq++;
1042  }
1043 
1044 #ifdef TRUNCATE_BLOCK
1045  /* Try to guess if it is profitable to stop the current block here */
1046  if ((s->last_lit & 0x1fff) == 0 && s->level > 2) {
1047  /* Compute an upper bound for the compressed length */
1048  ulg out_length = (ulg)s->last_lit*8L;
1049  ulg in_length = (ulg)((long)s->strstart - s->block_start);
1050  int dcode;
1051  for (dcode = 0; dcode < D_CODES; dcode++) {
1052  out_length += (ulg)s->dyn_dtree[dcode].Freq *
1053  (5L+extra_dbits[dcode]);
1054  }
1055  out_length >>= 3;
1056  Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ",
1057  s->last_lit, in_length, out_length,
1058  100L - out_length*100L/in_length));
1059  if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1;
1060  }
1061 #endif
1062  return (s->last_lit == s->lit_bufsize-1);
1063  /* We avoid equality with lit_bufsize because of wraparound at 64K
1064  * on 16 bit machines and because stored blocks are restricted to
1065  * 64K-1 bytes.
1066  */
1067 }
1068 
1069 /* ===========================================================================
1070  * Send the block data compressed using the given Huffman trees
1071  */
1072 local void compress_block(s, ltree, dtree)
1073  deflate_state *s;
1074  ct_data *ltree; /* literal tree */
1075  ct_data *dtree; /* distance tree */
1076 {
1077  unsigned dist; /* distance of matched string */
1078  int lc; /* match length or unmatched char (if dist == 0) */
1079  unsigned lx = 0; /* running index in l_buf */
1080  unsigned code; /* the code to send */
1081  int extra; /* number of extra bits to send */
1082 
1083  if (s->last_lit != 0) do {
1084  dist = s->d_buf[lx];
1085  lc = s->l_buf[lx++];
1086  if (dist == 0) {
1087  send_code(s, lc, ltree); /* send a literal byte */
1088  Tracecv(isgraph(lc), (stderr," '%c' ", lc));
1089  } else {
1090  /* Here, lc is the match length - MIN_MATCH */
1091  code = _length_code[lc];
1092  send_code(s, code+LITERALS+1, ltree); /* send the length code */
1093  extra = extra_lbits[code];
1094  if (extra != 0) {
1095  lc -= base_length[code];
1096  send_bits(s, lc, extra); /* send the extra length bits */
1097  }
1098  dist--; /* dist is now the match distance - 1 */
1099  code = d_code(dist);
1100  Assert (code < D_CODES, "bad d_code");
1101 
1102  send_code(s, code, dtree); /* send the distance code */
1103  extra = extra_dbits[code];
1104  if (extra != 0) {
1105  dist -= base_dist[code];
1106  send_bits(s, dist, extra); /* send the extra distance bits */
1107  }
1108  } /* literal or match pair ? */
1109 
1110  /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */
1111  Assert((uInt)(s->pending) < s->lit_bufsize + 2*lx,
1112  "pendingBuf overflow");
1113 
1114  } while (lx < s->last_lit);
1115 
1116  send_code(s, END_BLOCK, ltree);
1117  s->last_eob_len = ltree[END_BLOCK].Len;
1118 }
1119 
1120 /* ===========================================================================
1121  * Set the data type to BINARY or TEXT, using a crude approximation:
1122  * set it to Z_TEXT if all symbols are either printable characters (33 to 255)
1123  * or white spaces (9 to 13, or 32); or set it to Z_BINARY otherwise.
1124  * IN assertion: the fields Freq of dyn_ltree are set.
1125  */
1127  deflate_state *s;
1128 {
1129  int n;
1130 
1131  for (n = 0; n < 9; n++)
1132  if (s->dyn_ltree[n].Freq != 0)
1133  break;
1134  if (n == 9)
1135  for (n = 14; n < 32; n++)
1136  if (s->dyn_ltree[n].Freq != 0)
1137  break;
1138  s->strm->data_type = (n == 32) ? Z_TEXT : Z_BINARY;
1139 }
1140 
1141 /* ===========================================================================
1142  * Reverse the first len bits of a code, using straightforward code (a faster
1143  * method would use a table)
1144  * IN assertion: 1 <= len <= 15
1145  */
1146 local unsigned bi_reverse(code, len)
1147  unsigned code; /* the value to invert */
1148  int len; /* its bit length */
1149 {
1150  register unsigned res = 0;
1151  do {
1152  res |= code & 1;
1153  code >>= 1, res <<= 1;
1154  } while (--len > 0);
1155  return res >> 1;
1156 }
1157 
1158 /* ===========================================================================
1159  * Flush the bit buffer, keeping at most 7 bits in it.
1160  */
1162  deflate_state *s;
1163 {
1164  if (s->bi_valid == 16) {
1165  put_short(s, s->bi_buf);
1166  s->bi_buf = 0;
1167  s->bi_valid = 0;
1168  } else if (s->bi_valid >= 8) {
1169  put_byte(s, (Byte)s->bi_buf);
1170  s->bi_buf >>= 8;
1171  s->bi_valid -= 8;
1172  }
1173 }
1174 
1175 /* ===========================================================================
1176  * Flush the bit buffer and align the output on a byte boundary
1177  */
1179  deflate_state *s;
1180 {
1181  if (s->bi_valid > 8) {
1182  put_short(s, s->bi_buf);
1183  } else if (s->bi_valid > 0) {
1184  put_byte(s, (Byte)s->bi_buf);
1185  }
1186  s->bi_buf = 0;
1187  s->bi_valid = 0;
1188 #ifdef DEBUG
1189  s->bits_sent = (s->bits_sent+7) & ~7;
1190 #endif
1191 }
1192 
1193 /* ===========================================================================
1194  * Copy a stored block, storing first the length and its
1195  * one's complement if requested.
1196  */
1197 local void copy_block(s, buf, len, header)
1198  deflate_state *s;
1199  charf *buf; /* the input data */
1200  unsigned len; /* its length */
1201  int header; /* true if block header must be written */
1202 {
1203  bi_windup(s); /* align on byte boundary */
1204  s->last_eob_len = 8; /* enough lookahead for inflate */
1205 
1206  if (header) {
1207  put_short(s, (ush)len);
1208  put_short(s, (ush)~len);
1209 #ifdef DEBUG
1210  s->bits_sent += 2*16;
1211 #endif
1212  }
1213 #ifdef DEBUG
1214  s->bits_sent += (ulg)len<<3;
1215 #endif
1216  while (len--) {
1217  put_byte(s, *buf++);
1218  }
1219 }
local const int extra_dbits[D_CODES]
Definition: trees.c:65
#define Tracecv(c, x)
Definition: zutil.h:257
local ct_data static_dtree[D_CODES]
Definition: trees.c:97
ush FAR ushf
Definition: zutil.h:50
const intf * extra_bits
Definition: trees.c:123
#define STORED_BLOCK
Definition: zutil.h:76
#define BL_CODES
Definition: deflate.h:42
unsigned char Byte
Definition: zconf.h:261
#define MIN_MATCH
Definition: zutil.h:81
#define Z_UNKNOWN
Definition: zlib.h:199
#define MAX_BITS
Definition: deflate.h:48
#define Assert(cond, msg)
Definition: zutil.h:252
local void copy_block(deflate_state *s, charf *buf, unsigned len, int header)
Definition: trees.c:1197
#define END_BLOCK
Definition: trees.c:49
#define SMALLEST
Definition: trees.c:426
#define Tracev(x)
Definition: zutil.h:254
png_voidp int value
Definition: png.h:2113
void _tr_init(deflate_state *s)
Definition: trees.c:382
local int base_dist[D_CODES]
Definition: trees.c:114
local void pqdownheap(deflate_state *s, ct_data *tree, int k)
Definition: trees.c:455
local void gen_codes(ct_data *tree, int max_code, ushf *bl_count)
Definition: trees.c:577
local void init_block(deflate_state *s)
Definition: trees.c:411
#define LENGTH_CODES
Definition: deflate.h:30
#define REP_3_6
Definition: trees.c:52
local static_tree_desc static_d_desc
Definition: trees.c:132
ct_data * dyn_tree
Definition: deflate.h:81
static_tree_desc * stat_desc
Definition: deflate.h:83
#define for
png_bytep png_bytep png_size_t length
Definition: png.h:1541
png_uint_32 i
Definition: png.h:2735
#define Z_FIXED
Definition: zlib.h:192
local int base_length[LENGTH_CODES]
Definition: trees.c:111
#define smaller(tree, n, m, depth)
Definition: trees.c:445
#define MAX_DIST(s)
Definition: deflate.h:276
#define REPZ_11_138
Definition: trees.c:58
#define put_short(s, w)
Definition: trees.c:180
local void gen_bitlen(deflate_state *s, tree_desc *desc)
Definition: trees.c:490
int max_code
Definition: deflate.h:82
local unsigned bi_reverse(unsigned code, int len)
Definition: trees.c:1146
local void set_data_type(deflate_state *s)
Definition: trees.c:1126
#define LITERALS
Definition: deflate.h:33
void _tr_stored_block(deflate_state *s, charf *buf, ulg stored_len, int eof)
Definition: trees.c:867
local void send_all_trees(deflate_state *s, int lcodes, int dcodes, int blcodes)
Definition: trees.c:838
#define DIST_CODE_LEN
Definition: trees.c:85
local void tr_static_init OF((void))
local void compress_block(deflate_state *s, ct_data *ltree, ct_data *dtree)
Definition: trees.c:1072
#define Code
Definition: deflate.h:74
void _tr_align(deflate_state *s)
Definition: trees.c:892
#define MAX_BL_BITS
Definition: trees.c:46
#define send_bits(s, value, length)
Definition: trees.c:217
def j(str, encoding="cp932")
unsigned short ush
Definition: zutil.h:49
#define MAX_MATCH
Definition: zutil.h:82
#define HEAP_SIZE
Definition: deflate.h:45
local static_tree_desc static_bl_desc
Definition: trees.c:135
#define Len
Definition: deflate.h:76
#define put_byte(s, c)
Definition: deflate.h:268
local const int extra_lbits[LENGTH_CODES]
Definition: trees.c:62
local void tr_static_init()
Definition: trees.c:238
local const uch bl_order[BL_CODES]
Definition: trees.c:71
png_bytep buf
Definition: png.h:2729
#define Z_BINARY
Definition: zlib.h:196
ushf * d_buf
Definition: deflate.h:238
#define Trace(x)
Definition: zutil.h:253
local void send_tree(deflate_state *s, ct_data *tree, int max_code)
Definition: trees.c:752
#define pqremove(s, tree, top)
Definition: trees.c:434
Definition: inftrees.h:24
int FAR intf
Definition: zconf.h:273
uch _dist_code[DIST_CODE_LEN]
Definition: trees.c:102
local void scan_tree(deflate_state *s, ct_data *tree, int max_code)
Definition: trees.c:707
#define Buf_size
Definition: trees.c:76
#define d_code(dist)
Definition: deflate.h:290
int _tr_tally(deflate_state *s, unsigned dist, unsigned lc)
Definition: trees.c:1022
unsigned char uch
Definition: zutil.h:47
uch _length_code[MAX_MATCH-MIN_MATCH+1]
Definition: trees.c:108
unsigned long ulg
Definition: zutil.h:51
local void bi_windup(deflate_state *s)
Definition: trees.c:1178
#define Freq
Definition: deflate.h:73
local void build_tree(deflate_state *s, tree_desc *desc)
Definition: trees.c:619
local int build_bl_tree(deflate_state *s)
Definition: trees.c:803
#define local
Definition: crc32.c:31
#define STATIC_TREES
Definition: zutil.h:77
void _tr_flush_block(deflate_state *s, charf *buf, ulg stored_len, int eof)
Definition: trees.c:921
const ct_data * static_tree
Definition: trees.c:122
local ct_data static_ltree[L_CODES+2]
Definition: trees.c:90
#define D_CODES
Definition: deflate.h:39
#define REPZ_3_10
Definition: trees.c:55
local const int extra_blbits[BL_CODES]
Definition: trees.c:68
#define DYN_TREES
Definition: zutil.h:78
#define Z_TEXT
Definition: zlib.h:197
#define send_code(s, c, tree)
Definition: trees.c:167
local void bi_flush(deflate_state *s)
Definition: trees.c:1161
unsigned int uInt
Definition: zconf.h:263
char FAR charf
Definition: zconf.h:272
local static_tree_desc static_l_desc
Definition: trees.c:129
#define Tracevv(x)
Definition: zutil.h:255
#define L_CODES
Definition: deflate.h:36


openhrp3
Author(s): AIST, General Robotix Inc., Nakamura Lab of Dept. of Mechano Informatics at University of Tokyo
autogenerated on Sat Apr 13 2019 02:14:25