File Coverage

deps/libgit2/deps/zlib/trees.c
Criterion Covered Total %
statement 252 301 83.7
branch 179 224 79.9
condition n/a
subroutine n/a
pod n/a
total 431 525 82.1


line stmt bran cond sub pod time code
1             /* trees.c -- output deflated data using Huffman coding
2             * Copyright (C) 1995-2021 Jean-loup Gailly
3             * detect_data_type() function provided freely by Cosmin Truta, 2006
4             * For conditions of distribution and use, see copyright notice in zlib.h
5             */
6              
7             /*
8             * ALGORITHM
9             *
10             * The "deflation" process uses several Huffman trees. The more
11             * common source values are represented by shorter bit sequences.
12             *
13             * Each code tree is stored in a compressed form which is itself
14             * a Huffman encoding of the lengths of all the code strings (in
15             * ascending order by source values). The actual code strings are
16             * reconstructed from the lengths in the inflate process, as described
17             * in the deflate specification.
18             *
19             * REFERENCES
20             *
21             * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification".
22             * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc
23             *
24             * Storer, James A.
25             * Data Compression: Methods and Theory, pp. 49-50.
26             * Computer Science Press, 1988. ISBN 0-7167-8156-5.
27             *
28             * Sedgewick, R.
29             * Algorithms, p290.
30             * Addison-Wesley, 1983. ISBN 0-201-06672-6.
31             */
32              
33             /* @(#) $Id$ */
34              
35             /* #define GEN_TREES_H */
36              
37             #include "deflate.h"
38              
39             #ifdef ZLIB_DEBUG
40             # include
41             #endif
42              
43             /* ===========================================================================
44             * Constants
45             */
46              
47             #define MAX_BL_BITS 7
48             /* Bit length codes must not exceed MAX_BL_BITS bits */
49              
50             #define END_BLOCK 256
51             /* end of block literal code */
52              
53             #define REP_3_6 16
54             /* repeat previous bit length 3-6 times (2 bits of repeat count) */
55              
56             #define REPZ_3_10 17
57             /* repeat a zero length 3-10 times (3 bits of repeat count) */
58              
59             #define REPZ_11_138 18
60             /* repeat a zero length 11-138 times (7 bits of repeat count) */
61              
62             local const int extra_lbits[LENGTH_CODES] /* extra bits for each length code */
63             = {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};
64              
65             local const int extra_dbits[D_CODES] /* extra bits for each distance code */
66             = {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};
67              
68             local const int extra_blbits[BL_CODES]/* extra bits for each bit length code */
69             = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7};
70              
71             local const uch bl_order[BL_CODES]
72             = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15};
73             /* The lengths of the bit length codes are sent in order of decreasing
74             * probability, to avoid transmitting the lengths for unused bit length codes.
75             */
76              
77             /* ===========================================================================
78             * Local data. These are initialized only once.
79             */
80              
81             #define DIST_CODE_LEN 512 /* see definition of array dist_code below */
82              
83             #if defined(GEN_TREES_H) || !defined(STDC)
84             /* non ANSI compilers may not accept trees.h */
85              
86             local ct_data static_ltree[L_CODES+2];
87             /* The static literal tree. Since the bit lengths are imposed, there is no
88             * need for the L_CODES extra codes used during heap construction. However
89             * The codes 286 and 287 are needed to build a canonical tree (see _tr_init
90             * below).
91             */
92              
93             local ct_data static_dtree[D_CODES];
94             /* The static distance tree. (Actually a trivial tree since all codes use
95             * 5 bits.)
96             */
97              
98             uch _dist_code[DIST_CODE_LEN];
99             /* Distance codes. The first 256 values correspond to the distances
100             * 3 .. 258, the last 256 values correspond to the top 8 bits of
101             * the 15 bit distances.
102             */
103              
104             uch _length_code[MAX_MATCH-MIN_MATCH+1];
105             /* length code for each normalized match length (0 == MIN_MATCH) */
106              
107             local int base_length[LENGTH_CODES];
108             /* First normalized length for each code (0 = MIN_MATCH) */
109              
110             local int base_dist[D_CODES];
111             /* First normalized distance for each code (0 = distance of 1) */
112              
113             #else
114             # include "trees.h"
115             #endif /* GEN_TREES_H */
116              
117             struct static_tree_desc_s {
118             const ct_data *static_tree; /* static tree or NULL */
119             const intf *extra_bits; /* extra bits for each code or NULL */
120             int extra_base; /* base index for extra_bits */
121             int elems; /* max number of elements in the tree */
122             int max_length; /* max bit length for the codes */
123             };
124              
125             local const static_tree_desc static_l_desc =
126             {static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS};
127              
128             local const static_tree_desc static_d_desc =
129             {static_dtree, extra_dbits, 0, D_CODES, MAX_BITS};
130              
131             local const static_tree_desc static_bl_desc =
132             {(const ct_data *)0, extra_blbits, 0, BL_CODES, MAX_BL_BITS};
133              
134             /* ===========================================================================
135             * Local (static) routines in this file.
136             */
137              
138             local void tr_static_init OF((void));
139             local void init_block OF((deflate_state *s));
140             local void pqdownheap OF((deflate_state *s, ct_data *tree, int k));
141             local void gen_bitlen OF((deflate_state *s, tree_desc *desc));
142             local void gen_codes OF((ct_data *tree, int max_code, ushf *bl_count));
143             local void build_tree OF((deflate_state *s, tree_desc *desc));
144             local void scan_tree OF((deflate_state *s, ct_data *tree, int max_code));
145             local void send_tree OF((deflate_state *s, ct_data *tree, int max_code));
146             local int build_bl_tree OF((deflate_state *s));
147             local void send_all_trees OF((deflate_state *s, int lcodes, int dcodes,
148             int blcodes));
149             local void compress_block OF((deflate_state *s, const ct_data *ltree,
150             const ct_data *dtree));
151             local int detect_data_type OF((deflate_state *s));
152             local unsigned bi_reverse OF((unsigned code, int len));
153             local void bi_windup OF((deflate_state *s));
154             local void bi_flush OF((deflate_state *s));
155              
156             #ifdef GEN_TREES_H
157             local void gen_trees_header OF((void));
158             #endif
159              
160             #ifndef ZLIB_DEBUG
161             # define send_code(s, c, tree) send_bits(s, tree[c].Code, tree[c].Len)
162             /* Send a code of the given tree. c and tree must not have side effects */
163              
164             #else /* !ZLIB_DEBUG */
165             # define send_code(s, c, tree) \
166             { if (z_verbose>2) fprintf(stderr,"\ncd %3d ",(c)); \
167             send_bits(s, tree[c].Code, tree[c].Len); }
168             #endif
169              
170             /* ===========================================================================
171             * Output a short LSB first on the stream.
172             * IN assertion: there is enough room in pendingBuf.
173             */
174             #define put_short(s, w) { \
175             put_byte(s, (uch)((w) & 0xff)); \
176             put_byte(s, (uch)((ush)(w) >> 8)); \
177             }
178              
179             /* ===========================================================================
180             * Send a value on a given number of bits.
181             * IN assertion: length <= 16 and value fits in length bits.
182             */
183             #ifdef ZLIB_DEBUG
184             local void send_bits OF((deflate_state *s, int value, int length));
185              
186             local void send_bits(s, value, length)
187             deflate_state *s;
188             int value; /* value to send */
189             int length; /* number of bits */
190             {
191             Tracevv((stderr," l %2d v %4x ", length, value));
192             Assert(length > 0 && length <= 15, "invalid length");
193             s->bits_sent += (ulg)length;
194              
195             /* If not enough room in bi_buf, use (valid) bits from bi_buf and
196             * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid))
197             * unused bits in value.
198             */
199             if (s->bi_valid > (int)Buf_size - length) {
200             s->bi_buf |= (ush)value << s->bi_valid;
201             put_short(s, s->bi_buf);
202             s->bi_buf = (ush)value >> (Buf_size - s->bi_valid);
203             s->bi_valid += length - Buf_size;
204             } else {
205             s->bi_buf |= (ush)value << s->bi_valid;
206             s->bi_valid += length;
207             }
208             }
209             #else /* !ZLIB_DEBUG */
210              
211             #define send_bits(s, value, length) \
212             { int len = length;\
213             if (s->bi_valid > (int)Buf_size - len) {\
214             int val = (int)value;\
215             s->bi_buf |= (ush)val << s->bi_valid;\
216             put_short(s, s->bi_buf);\
217             s->bi_buf = (ush)val >> (Buf_size - s->bi_valid);\
218             s->bi_valid += len - Buf_size;\
219             } else {\
220             s->bi_buf |= (ush)(value) << s->bi_valid;\
221             s->bi_valid += len;\
222             }\
223             }
224             #endif /* ZLIB_DEBUG */
225              
226              
227             /* the arguments must not have side effects */
228              
229             /* ===========================================================================
230             * Initialize the various 'constant' tables.
231             */
232 241           local void tr_static_init()
233             {
234             #if defined(GEN_TREES_H) || !defined(STDC)
235             static int static_init_done = 0;
236             int n; /* iterates over tree elements */
237             int bits; /* bit counter */
238             int length; /* length value */
239             int code; /* code value */
240             int dist; /* distance index */
241             ush bl_count[MAX_BITS+1];
242             /* number of codes at each bit length for an optimal tree */
243              
244             if (static_init_done) return;
245              
246             /* For some embedded targets, global variables are not initialized: */
247             #ifdef NO_INIT_GLOBAL_POINTERS
248             static_l_desc.static_tree = static_ltree;
249             static_l_desc.extra_bits = extra_lbits;
250             static_d_desc.static_tree = static_dtree;
251             static_d_desc.extra_bits = extra_dbits;
252             static_bl_desc.extra_bits = extra_blbits;
253             #endif
254              
255             /* Initialize the mapping length (0..255) -> length code (0..28) */
256             length = 0;
257             for (code = 0; code < LENGTH_CODES-1; code++) {
258             base_length[code] = length;
259             for (n = 0; n < (1<
260             _length_code[length++] = (uch)code;
261             }
262             }
263             Assert (length == 256, "tr_static_init: length != 256");
264             /* Note that the length 255 (match length 258) can be represented
265             * in two different ways: code 284 + 5 bits or code 285, so we
266             * overwrite length_code[255] to use the best encoding:
267             */
268             _length_code[length-1] = (uch)code;
269              
270             /* Initialize the mapping dist (0..32K) -> dist code (0..29) */
271             dist = 0;
272             for (code = 0 ; code < 16; code++) {
273             base_dist[code] = dist;
274             for (n = 0; n < (1<
275             _dist_code[dist++] = (uch)code;
276             }
277             }
278             Assert (dist == 256, "tr_static_init: dist != 256");
279             dist >>= 7; /* from now on, all distances are divided by 128 */
280             for ( ; code < D_CODES; code++) {
281             base_dist[code] = dist << 7;
282             for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) {
283             _dist_code[256 + dist++] = (uch)code;
284             }
285             }
286             Assert (dist == 256, "tr_static_init: 256+dist != 512");
287              
288             /* Construct the codes of the static literal tree */
289             for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0;
290             n = 0;
291             while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++;
292             while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++;
293             while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++;
294             while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++;
295             /* Codes 286 and 287 do not exist, but we must include them in the
296             * tree construction to get a canonical Huffman tree (longest code
297             * all ones)
298             */
299             gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count);
300              
301             /* The static distance tree is trivial: */
302             for (n = 0; n < D_CODES; n++) {
303             static_dtree[n].Len = 5;
304             static_dtree[n].Code = bi_reverse((unsigned)n, 5);
305             }
306             static_init_done = 1;
307              
308             # ifdef GEN_TREES_H
309             gen_trees_header();
310             # endif
311             #endif /* defined(GEN_TREES_H) || !defined(STDC) */
312 241           }
313              
314             /* ===========================================================================
315             * Genererate the file trees.h describing the static trees.
316             */
317             #ifdef GEN_TREES_H
318             # ifndef ZLIB_DEBUG
319             # include
320             # endif
321              
322             # define SEPARATOR(i, last, width) \
323             ((i) == (last)? "\n};\n\n" : \
324             ((i) % (width) == (width)-1 ? ",\n" : ", "))
325              
326             void gen_trees_header()
327             {
328             FILE *header = fopen("trees.h", "w");
329             int i;
330              
331             Assert (header != NULL, "Can't open trees.h");
332             fprintf(header,
333             "/* header created automatically with -DGEN_TREES_H */\n\n");
334              
335             fprintf(header, "local const ct_data static_ltree[L_CODES+2] = {\n");
336             for (i = 0; i < L_CODES+2; i++) {
337             fprintf(header, "{{%3u},{%3u}}%s", static_ltree[i].Code,
338             static_ltree[i].Len, SEPARATOR(i, L_CODES+1, 5));
339             }
340              
341             fprintf(header, "local const ct_data static_dtree[D_CODES] = {\n");
342             for (i = 0; i < D_CODES; i++) {
343             fprintf(header, "{{%2u},{%2u}}%s", static_dtree[i].Code,
344             static_dtree[i].Len, SEPARATOR(i, D_CODES-1, 5));
345             }
346              
347             fprintf(header, "const uch ZLIB_INTERNAL _dist_code[DIST_CODE_LEN] = {\n");
348             for (i = 0; i < DIST_CODE_LEN; i++) {
349             fprintf(header, "%2u%s", _dist_code[i],
350             SEPARATOR(i, DIST_CODE_LEN-1, 20));
351             }
352              
353             fprintf(header,
354             "const uch ZLIB_INTERNAL _length_code[MAX_MATCH-MIN_MATCH+1]= {\n");
355             for (i = 0; i < MAX_MATCH-MIN_MATCH+1; i++) {
356             fprintf(header, "%2u%s", _length_code[i],
357             SEPARATOR(i, MAX_MATCH-MIN_MATCH, 20));
358             }
359              
360             fprintf(header, "local const int base_length[LENGTH_CODES] = {\n");
361             for (i = 0; i < LENGTH_CODES; i++) {
362             fprintf(header, "%1u%s", base_length[i],
363             SEPARATOR(i, LENGTH_CODES-1, 20));
364             }
365              
366             fprintf(header, "local const int base_dist[D_CODES] = {\n");
367             for (i = 0; i < D_CODES; i++) {
368             fprintf(header, "%5u%s", base_dist[i],
369             SEPARATOR(i, D_CODES-1, 10));
370             }
371              
372             fclose(header);
373             }
374             #endif /* GEN_TREES_H */
375              
376             /* ===========================================================================
377             * Initialize the tree data structures for a new zlib stream.
378             */
379 241           void ZLIB_INTERNAL _tr_init(s)
380             deflate_state *s;
381             {
382 241           tr_static_init();
383              
384 241           s->l_desc.dyn_tree = s->dyn_ltree;
385 241           s->l_desc.stat_desc = &static_l_desc;
386              
387 241           s->d_desc.dyn_tree = s->dyn_dtree;
388 241           s->d_desc.stat_desc = &static_d_desc;
389              
390 241           s->bl_desc.dyn_tree = s->bl_tree;
391 241           s->bl_desc.stat_desc = &static_bl_desc;
392              
393 241           s->bi_buf = 0;
394 241           s->bi_valid = 0;
395             #ifdef ZLIB_DEBUG
396             s->compressed_len = 0L;
397             s->bits_sent = 0L;
398             #endif
399              
400             /* Initialize the first block of the first file: */
401 241           init_block(s);
402 241           }
403              
404             /* ===========================================================================
405             * Initialize a new block.
406             */
407 455           local void init_block(s)
408             deflate_state *s;
409             {
410             int n; /* iterates over tree elements */
411              
412             /* Initialize the trees. */
413 130585 100         for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0;
414 14105 100         for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0;
415 9100 100         for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0;
416              
417 455           s->dyn_ltree[END_BLOCK].Freq = 1;
418 455           s->opt_len = s->static_len = 0L;
419 455           s->sym_next = s->matches = 0;
420 455           }
421              
422             #define SMALLEST 1
423             /* Index within the heap array of least frequent node in the Huffman tree */
424              
425              
426             /* ===========================================================================
427             * Remove the smallest element from the heap and recreate the heap with
428             * one less element. Updates heap and heap_len.
429             */
430             #define pqremove(s, tree, top) \
431             {\
432             top = s->heap[SMALLEST]; \
433             s->heap[SMALLEST] = s->heap[s->heap_len--]; \
434             pqdownheap(s, tree, SMALLEST); \
435             }
436              
437             /* ===========================================================================
438             * Compares to subtrees, using the tree depth as tie breaker when
439             * the subtrees have equal frequency. This minimizes the worst case length.
440             */
441             #define smaller(tree, n, m, depth) \
442             (tree[n].Freq < tree[m].Freq || \
443             (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m]))
444              
445             /* ===========================================================================
446             * Restore the heap property by moving down the tree starting at node k,
447             * exchanging a node with the smallest of its two sons if necessary, stopping
448             * when the heap property is re-established (each father smaller than its
449             * two sons).
450             */
451 23218           local void pqdownheap(s, tree, k)
452             deflate_state *s;
453             ct_data *tree; /* the tree to restore */
454             int k; /* node to move down */
455             {
456 23218           int v = s->heap[k];
457 23218           int j = k << 1; /* left son of k */
458 71378 100         while (j <= s->heap_len) {
459             /* Set j to the smallest of the two sons: */
460 55864 100         if (j < s->heap_len &&
    100          
461 45951 100         smaller(tree, s->heap[j+1], s->heap[j], s->depth)) {
    100          
462 26299           j++;
463             }
464             /* Exit if v is smaller than both sons */
465 55864 100         if (smaller(tree, v, s->heap[j], s->depth)) break;
    100          
    100          
466              
467             /* Exchange v with the smallest son */
468 48160           s->heap[k] = s->heap[j]; k = j;
469              
470             /* And continue down the tree, setting j to the left son of k */
471 48160           j <<= 1;
472             }
473 23218           s->heap[k] = v;
474 23218           }
475              
476             /* ===========================================================================
477             * Compute the optimal bit lengths for a tree and update the total bit length
478             * for the current block.
479             * IN assertion: the fields freq and dad are set, heap[heap_max] and
480             * above are the tree nodes sorted by increasing frequency.
481             * OUT assertions: the field len is set to the optimal bit length, the
482             * array bl_count contains the frequencies for each bit length.
483             * The length opt_len is updated; static_len is also updated if stree is
484             * not null.
485             */
486 642           local void gen_bitlen(s, desc)
487             deflate_state *s;
488             tree_desc *desc; /* the tree descriptor */
489             {
490 642           ct_data *tree = desc->dyn_tree;
491 642           int max_code = desc->max_code;
492 642           const ct_data *stree = desc->stat_desc->static_tree;
493 642           const intf *extra = desc->stat_desc->extra_bits;
494 642           int base = desc->stat_desc->extra_base;
495 642           int max_length = desc->stat_desc->max_length;
496             int h; /* heap index */
497             int n, m; /* iterate over the tree elements */
498             int bits; /* bit length */
499             int xbits; /* extra bits */
500             ush f; /* frequency */
501 642           int overflow = 0; /* number of elements with bit length too large */
502              
503 10914 100         for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0;
504              
505             /* In a first pass, compute the optimal bit lengths (which may
506             * overflow in the case of the bit length tree).
507             */
508 642           tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */
509              
510 19050 100         for (h = s->heap_max+1; h < HEAP_SIZE; h++) {
511 18408           n = s->heap[h];
512 18408           bits = tree[tree[n].Dad].Len + 1;
513 18408 50         if (bits > max_length) bits = max_length, overflow++;
514 18408           tree[n].Len = (ush)bits;
515             /* We overwrite tree[n].Dad which is no longer needed */
516              
517 18408 100         if (n > max_code) continue; /* not a leaf node */
518              
519 9846           s->bl_count[bits]++;
520 9846           xbits = 0;
521 9846 100         if (n >= base) xbits = extra[n-base];
522 9846           f = tree[n].Freq;
523 9846           s->opt_len += (ulg)f * (unsigned)(bits + xbits);
524 9846 100         if (stree) s->static_len += (ulg)f * (unsigned)(stree[n].Len + xbits);
525             }
526 642 50         if (overflow == 0) return;
527              
528             Tracev((stderr,"\nbit length overflow\n"));
529             /* This happens for example on obj2 and pic of the Calgary corpus */
530              
531             /* Find the first bit length which could increase: */
532             do {
533 0           bits = max_length-1;
534 0 0         while (s->bl_count[bits] == 0) bits--;
535 0           s->bl_count[bits]--; /* move one leaf down the tree */
536 0           s->bl_count[bits+1] += 2; /* move one overflow item as its brother */
537 0           s->bl_count[max_length]--;
538             /* The brother of the overflow item also moves one step up,
539             * but this does not affect bl_count[max_length]
540             */
541 0           overflow -= 2;
542 0 0         } while (overflow > 0);
543              
544             /* Now recompute all bit lengths, scanning in increasing frequency.
545             * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all
546             * lengths instead of fixing only the wrong ones. This idea is taken
547             * from 'ar' written by Haruhiko Okumura.)
548             */
549 0 0         for (bits = max_length; bits != 0; bits--) {
550 0           n = s->bl_count[bits];
551 0 0         while (n != 0) {
552 0           m = s->heap[--h];
553 0 0         if (m > max_code) continue;
554 0 0         if ((unsigned) tree[m].Len != (unsigned) bits) {
555             Tracev((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits));
556 0           s->opt_len += ((ulg)bits - tree[m].Len) * tree[m].Freq;
557 0           tree[m].Len = (ush)bits;
558             }
559 0           n--;
560             }
561             }
562             }
563              
564             /* ===========================================================================
565             * Generate the codes for a given tree and bit counts (which need not be
566             * optimal).
567             * IN assertion: the array bl_count contains the bit length statistics for
568             * the given tree and the field len is set for all tree elements.
569             * OUT assertion: the field code is set for all tree elements of non
570             * zero code length.
571             */
572 642           local void gen_codes (tree, max_code, bl_count)
573             ct_data *tree; /* the tree to decorate */
574             int max_code; /* largest code with non zero frequency */
575             ushf *bl_count; /* number of codes at each bit length */
576             {
577             ush next_code[MAX_BITS+1]; /* next code value for each bit length */
578 642           unsigned code = 0; /* running code value */
579             int bits; /* bit index */
580             int n; /* code index */
581              
582             /* The distribution counts are first used to generate the code values
583             * without bit reversal.
584             */
585 10272 100         for (bits = 1; bits <= MAX_BITS; bits++) {
586 9630           code = (code + bl_count[bits-1]) << 1;
587 9630           next_code[bits] = (ush)code;
588             }
589             /* Check that the bit counts in bl_count are consistent. The last code
590             * must be all ones.
591             */
592             Assert (code + bl_count[MAX_BITS]-1 == (1<
593             "inconsistent bit counts");
594             Tracev((stderr,"\ngen_codes: max_code %d ", max_code));
595              
596 63073 100         for (n = 0; n <= max_code; n++) {
597 62431           int len = tree[n].Len;
598 62431 100         if (len == 0) continue;
599             /* Now reverse the bits */
600 9846           tree[n].Code = (ush)bi_reverse(next_code[len]++, len);
601              
602             Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
603             n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1));
604             }
605 642           }
606              
607             /* ===========================================================================
608             * Construct one Huffman tree and assigns the code bit strings and lengths.
609             * Update the total bit length for the current block.
610             * IN assertion: the field freq is set for all tree elements.
611             * OUT assertions: the fields len and code are set to the optimal bit length
612             * and corresponding code. The length opt_len is updated; static_len is
613             * also updated if stree is not null. The field max_code is set.
614             */
615 642           local void build_tree(s, desc)
616             deflate_state *s;
617             tree_desc *desc; /* the tree descriptor */
618             {
619 642           ct_data *tree = desc->dyn_tree;
620 642           const ct_data *stree = desc->stat_desc->static_tree;
621 642           int elems = desc->stat_desc->elems;
622             int n, m; /* iterate over heap elements */
623 642           int max_code = -1; /* largest code with non zero frequency */
624             int node; /* new node being created */
625              
626             /* Construct the initial heap, with least frequent element in
627             * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1].
628             * heap[0] is not used.
629             */
630 642           s->heap_len = 0, s->heap_max = HEAP_SIZE;
631              
632 72332 100         for (n = 0; n < elems; n++) {
633 71690 100         if (tree[n].Freq != 0) {
634 9684           s->heap[++(s->heap_len)] = max_code = n;
635 9684           s->depth[n] = 0;
636             } else {
637 62006           tree[n].Len = 0;
638             }
639             }
640              
641             /* The pkzip format requires that at least one distance code exists,
642             * and that at least one bit should be sent even if there is only one
643             * possible code. So to avoid special checks later on we force at least
644             * two codes of non zero frequency.
645             */
646 804 100         while (s->heap_len < 2) {
647 162 100         node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0);
648 162           tree[node].Freq = 1;
649 162           s->depth[node] = 0;
650 162 50         s->opt_len--; if (stree) s->static_len -= stree[node].Len;
651             /* node is 0 or 1 so it does not have extra bits */
652             }
653 642           desc->max_code = max_code;
654              
655             /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,
656             * establish sub-heaps of increasing lengths:
657             */
658 5452 100         for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n);
659              
660             /* Construct the Huffman tree by repeatedly combining the least two
661             * frequent nodes.
662             */
663 642           node = elems; /* next internal node of the tree */
664             do {
665 9204           pqremove(s, tree, n); /* n = node of least frequency */
666 9204           m = s->heap[SMALLEST]; /* m = node of next least frequency */
667              
668 9204           s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */
669 9204           s->heap[--(s->heap_max)] = m;
670              
671             /* Create a new node father of n and m */
672 9204           tree[node].Freq = tree[n].Freq + tree[m].Freq;
673 9204 100         s->depth[node] = (uch)((s->depth[n] >= s->depth[m] ?
674 9204           s->depth[n] : s->depth[m]) + 1);
675 9204           tree[n].Dad = tree[m].Dad = (ush)node;
676             #ifdef DUMP_BL_TREE
677             if (tree == s->bl_tree) {
678             fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)",
679             node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq);
680             }
681             #endif
682             /* and insert the new node in the heap */
683 9204           s->heap[SMALLEST] = node++;
684 9204           pqdownheap(s, tree, SMALLEST);
685              
686 9204 100         } while (s->heap_len >= 2);
687              
688 642           s->heap[--(s->heap_max)] = s->heap[SMALLEST];
689              
690             /* At this point, the fields freq and dad are set. We can now
691             * generate the bit lengths.
692             */
693 642           gen_bitlen(s, (tree_desc *)desc);
694              
695             /* The field len is now set, we can generate the bit codes */
696 642           gen_codes ((ct_data *)tree, max_code, s->bl_count);
697 642           }
698              
699             /* ===========================================================================
700             * Scan a literal or distance tree to determine the frequencies of the codes
701             * in the bit length tree.
702             */
703 428           local void scan_tree (s, tree, max_code)
704             deflate_state *s;
705             ct_data *tree; /* the tree to be scanned */
706             int max_code; /* and its largest code of non zero frequency */
707             {
708             int n; /* iterates over all tree elements */
709 428           int prevlen = -1; /* last emitted length */
710             int curlen; /* length of current code */
711 428           int nextlen = tree[0].Len; /* length of next code */
712 428           int count = 0; /* repeat count of the current code */
713 428           int max_count = 7; /* max repeat count */
714 428           int min_count = 4; /* min repeat count */
715              
716 428 100         if (nextlen == 0) max_count = 138, min_count = 3;
717 428           tree[max_code+1].Len = (ush)0xffff; /* guard */
718              
719 58794 100         for (n = 0; n <= max_code; n++) {
720 58366           curlen = nextlen; nextlen = tree[n+1].Len;
721 58366 100         if (++count < max_count && curlen == nextlen) {
    100          
722 47022           continue;
723 11344 100         } else if (count < min_count) {
724 8587           s->bl_tree[curlen].Freq += count;
725 2757 100         } else if (curlen != 0) {
726 68 100         if (curlen != prevlen) s->bl_tree[curlen].Freq++;
727 68           s->bl_tree[REP_3_6].Freq++;
728 2689 100         } else if (count <= 10) {
729 1726           s->bl_tree[REPZ_3_10].Freq++;
730             } else {
731 963           s->bl_tree[REPZ_11_138].Freq++;
732             }
733 11344           count = 0; prevlen = curlen;
734 11344 100         if (nextlen == 0) {
735 4495           max_count = 138, min_count = 3;
736 6849 100         } else if (curlen == nextlen) {
737 5           max_count = 6, min_count = 3;
738             } else {
739 6844           max_count = 7, min_count = 4;
740             }
741             }
742 428           }
743              
744             /* ===========================================================================
745             * Send a literal or distance tree in compressed form, using the codes in
746             * bl_tree.
747             */
748 124           local void send_tree (s, tree, max_code)
749             deflate_state *s;
750             ct_data *tree; /* the tree to be scanned */
751             int max_code; /* and its largest code of non zero frequency */
752             {
753             int n; /* iterates over all tree elements */
754 124           int prevlen = -1; /* last emitted length */
755             int curlen; /* length of current code */
756 124           int nextlen = tree[0].Len; /* length of next code */
757 124           int count = 0; /* repeat count of the current code */
758 124           int max_count = 7; /* max repeat count */
759 124           int min_count = 4; /* min repeat count */
760              
761             /* tree[max_code+1].Len = -1; */ /* guard already set */
762 124 100         if (nextlen == 0) max_count = 138, min_count = 3;
763              
764 18069 100         for (n = 0; n <= max_code; n++) {
765 17945           curlen = nextlen; nextlen = tree[n+1].Len;
766 17945 100         if (++count < max_count && curlen == nextlen) {
    100          
767 14108           continue;
768 3837 100         } else if (count < min_count) {
769 3798 100         do { send_code(s, curlen, s->bl_tree); } while (--count != 0);
    100          
770              
771 637 100         } else if (curlen != 0) {
772 41 100         if (curlen != prevlen) {
773 40 100         send_code(s, curlen, s->bl_tree); count--;
774             }
775             Assert(count >= 3 && count <= 6, " 3_6?");
776 41 100         send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2);
    100          
777              
778 596 100         } else if (count <= 10) {
779 353 100         send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3);
    100          
780              
781             } else {
782 243 100         send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7);
    100          
783             }
784 3837           count = 0; prevlen = curlen;
785 3837 100         if (nextlen == 0) {
786 1208           max_count = 138, min_count = 3;
787 2629 100         } else if (curlen == nextlen) {
788 5           max_count = 6, min_count = 3;
789             } else {
790 2624           max_count = 7, min_count = 4;
791             }
792             }
793 124           }
794              
795             /* ===========================================================================
796             * Construct the Huffman tree for the bit lengths and return the index in
797             * bl_order of the last bit length code to send.
798             */
799 214           local int build_bl_tree(s)
800             deflate_state *s;
801             {
802             int max_blindex; /* index of last bit length code of non zero freq */
803              
804             /* Determine the bit length frequencies for literal and distance trees */
805 214           scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code);
806 214           scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code);
807              
808             /* Build the bit length tree: */
809 214           build_tree(s, (tree_desc *)(&(s->bl_desc)));
810             /* opt_len now includes the length of the tree representations, except
811             * the lengths of the bit lengths codes and the 5+5+4 bits for the counts.
812             */
813              
814             /* Determine the number of bit length codes to send. The pkzip format
815             * requires that at least 4 bit length codes be sent. (appnote.txt says
816             * 3 but the actual value used is 4.)
817             */
818 568 50         for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) {
819 568 100         if (s->bl_tree[bl_order[max_blindex]].Len != 0) break;
820             }
821             /* Update opt_len to include the bit length tree and counts */
822 214           s->opt_len += 3*((ulg)max_blindex+1) + 5+5+4;
823             Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld",
824             s->opt_len, s->static_len));
825              
826 214           return max_blindex;
827             }
828              
829             /* ===========================================================================
830             * Send the header for a block using dynamic Huffman trees: the counts, the
831             * lengths of the bit length codes, the literal tree and the distance tree.
832             * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4.
833             */
834 62           local void send_all_trees(s, lcodes, dcodes, blcodes)
835             deflate_state *s;
836             int lcodes, dcodes, blcodes; /* number of codes for each tree */
837             {
838             int rank; /* index in bl_order */
839              
840             Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes");
841             Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES,
842             "too many codes");
843             Tracev((stderr, "\nbl counts: "));
844 62 50         send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */
845 62 50         send_bits(s, dcodes-1, 5);
846 62 50         send_bits(s, blcodes-4, 4); /* not -3 as stated in appnote.txt */
847 1056 100         for (rank = 0; rank < blcodes; rank++) {
848             Tracev((stderr, "\nbl code %2d ", bl_order[rank]));
849 994 100         send_bits(s, s->bl_tree[bl_order[rank]].Len, 3);
850             }
851             Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent));
852              
853 62           send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */
854             Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent));
855              
856 62           send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */
857             Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent));
858 62           }
859              
860             /* ===========================================================================
861             * Send a stored block
862             */
863 0           void ZLIB_INTERNAL _tr_stored_block(s, buf, stored_len, last)
864             deflate_state *s;
865             charf *buf; /* input block */
866             ulg stored_len; /* length of input block */
867             int last; /* one if this is the last block for a file */
868             {
869 0 0         send_bits(s, (STORED_BLOCK<<1)+last, 3); /* send block type */
870 0           bi_windup(s); /* align on byte boundary */
871 0           put_short(s, (ush)stored_len);
872 0           put_short(s, (ush)~stored_len);
873 0 0         if (stored_len)
874 0           zmemcpy(s->pending_buf + s->pending, (Bytef *)buf, stored_len);
875 0           s->pending += stored_len;
876             #ifdef ZLIB_DEBUG
877             s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L;
878             s->compressed_len += (stored_len + 4) << 3;
879             s->bits_sent += 2*16;
880             s->bits_sent += stored_len<<3;
881             #endif
882 0           }
883              
884             /* ===========================================================================
885             * Flush the bits in the bit buffer to pending output (leaves at most 7 bits)
886             */
887 645           void ZLIB_INTERNAL _tr_flush_bits(s)
888             deflate_state *s;
889             {
890 645           bi_flush(s);
891 645           }
892              
893             /* ===========================================================================
894             * Send one empty static block to give enough lookahead for inflate.
895             * This takes 10 bits, of which 7 may remain in the bit buffer.
896             */
897 0           void ZLIB_INTERNAL _tr_align(s)
898             deflate_state *s;
899             {
900 0 0         send_bits(s, STATIC_TREES<<1, 3);
901 0 0         send_code(s, END_BLOCK, static_ltree);
902             #ifdef ZLIB_DEBUG
903             s->compressed_len += 10L; /* 3 for block type, 7 for EOB */
904             #endif
905 0           bi_flush(s);
906 0           }
907              
908             /* ===========================================================================
909             * Determine the best encoding for the current block: dynamic trees, static
910             * trees or store, and write out the encoded block.
911             */
912 214           void ZLIB_INTERNAL _tr_flush_block(s, buf, stored_len, last)
913             deflate_state *s;
914             charf *buf; /* input block, or NULL if too old */
915             ulg stored_len; /* length of input block */
916             int last; /* one if this is the last block for a file */
917             {
918             ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */
919 214           int max_blindex = 0; /* index of last bit length code of non zero freq */
920              
921             /* Build the Huffman trees unless a stored block is forced */
922 214 50         if (s->level > 0) {
923              
924             /* Check if the file is binary or text */
925 214 50         if (s->strm->data_type == Z_UNKNOWN)
926 214           s->strm->data_type = detect_data_type(s);
927              
928             /* Construct the literal and distance trees */
929 214           build_tree(s, (tree_desc *)(&(s->l_desc)));
930             Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len,
931             s->static_len));
932              
933 214           build_tree(s, (tree_desc *)(&(s->d_desc)));
934             Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len,
935             s->static_len));
936             /* At this point, opt_len and static_len are the total bit lengths of
937             * the compressed block data, excluding the tree representations.
938             */
939              
940             /* Build the bit length tree for the above two trees, and get the index
941             * in bl_order of the last bit length code to send.
942             */
943 214           max_blindex = build_bl_tree(s);
944              
945             /* Determine the best encoding. Compute the block lengths in bytes. */
946 214           opt_lenb = (s->opt_len+3+7)>>3;
947 214           static_lenb = (s->static_len+3+7)>>3;
948              
949             Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ",
950             opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len,
951             s->sym_next / 3));
952              
953 214 100         if (static_lenb <= opt_lenb) opt_lenb = static_lenb;
954              
955             } else {
956             Assert(buf != (char*)0, "lost buf");
957 0           opt_lenb = static_lenb = stored_len + 5; /* force a stored block */
958             }
959              
960             #ifdef FORCE_STORED
961             if (buf != (char*)0) { /* force stored block */
962             #else
963 214 50         if (stored_len+4 <= opt_lenb && buf != (char*)0) {
    0          
964             /* 4: two words for the lengths */
965             #endif
966             /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE.
967             * Otherwise we can't have processed more than WSIZE input bytes since
968             * the last block flush, because compression would have been
969             * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
970             * transform a block into a stored block.
971             */
972 0           _tr_stored_block(s, buf, stored_len, last);
973              
974             #ifdef FORCE_STATIC
975             } else if (static_lenb >= 0) { /* force static trees */
976             #else
977 214 50         } else if (s->strategy == Z_FIXED || static_lenb == opt_lenb) {
    100          
978             #endif
979 152 50         send_bits(s, (STATIC_TREES<<1)+last, 3);
980 152           compress_block(s, (const ct_data *)static_ltree,
981             (const ct_data *)static_dtree);
982             #ifdef ZLIB_DEBUG
983             s->compressed_len += 3 + s->static_len;
984             #endif
985             } else {
986 62 50         send_bits(s, (DYN_TREES<<1)+last, 3);
987 62           send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1,
988             max_blindex+1);
989 62           compress_block(s, (const ct_data *)s->dyn_ltree,
990 62           (const ct_data *)s->dyn_dtree);
991             #ifdef ZLIB_DEBUG
992             s->compressed_len += 3 + s->opt_len;
993             #endif
994             }
995             Assert (s->compressed_len == s->bits_sent, "bad compressed size");
996             /* The above check is made mod 2^32, for files larger than 512 MB
997             * and uLong implemented on 32 bits.
998             */
999 214           init_block(s);
1000              
1001 214 50         if (last) {
1002 214           bi_windup(s);
1003             #ifdef ZLIB_DEBUG
1004             s->compressed_len += 7; /* align on byte boundary */
1005             #endif
1006             }
1007             Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3,
1008             s->compressed_len-7*last));
1009 214           }
1010              
1011             /* ===========================================================================
1012             * Save the match info and tally the frequency counts. Return true if
1013             * the current block must be flushed.
1014             */
1015 0           int ZLIB_INTERNAL _tr_tally (s, dist, lc)
1016             deflate_state *s;
1017             unsigned dist; /* distance of matched string */
1018             unsigned lc; /* match length-MIN_MATCH or unmatched char (if dist==0) */
1019             {
1020 0           s->sym_buf[s->sym_next++] = (uch)dist;
1021 0           s->sym_buf[s->sym_next++] = (uch)(dist >> 8);
1022 0           s->sym_buf[s->sym_next++] = (uch)lc;
1023 0 0         if (dist == 0) {
1024             /* lc is the unmatched char */
1025 0           s->dyn_ltree[lc].Freq++;
1026             } else {
1027 0           s->matches++;
1028             /* Here, lc is the match length - MIN_MATCH */
1029 0           dist--; /* dist = match distance - 1 */
1030             Assert((ush)dist < (ush)MAX_DIST(s) &&
1031             (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) &&
1032             (ush)d_code(dist) < (ush)D_CODES, "_tr_tally: bad match");
1033              
1034 0           s->dyn_ltree[_length_code[lc]+LITERALS+1].Freq++;
1035 0 0         s->dyn_dtree[d_code(dist)].Freq++;
1036             }
1037 0           return (s->sym_next == s->sym_end);
1038             }
1039              
1040             /* ===========================================================================
1041             * Send the block data compressed using the given Huffman trees
1042             */
1043 214           local void compress_block(s, ltree, dtree)
1044             deflate_state *s;
1045             const ct_data *ltree; /* literal tree */
1046             const ct_data *dtree; /* distance tree */
1047             {
1048             unsigned dist; /* distance of matched string */
1049             int lc; /* match length or unmatched char (if dist == 0) */
1050 214           unsigned sx = 0; /* running index in sym_buf */
1051             unsigned code; /* the code to send */
1052             int extra; /* number of extra bits to send */
1053              
1054 214 100         if (s->sym_next != 0) do {
1055 16796           dist = s->sym_buf[sx++] & 0xff;
1056 16796           dist += (unsigned)(s->sym_buf[sx++] & 0xff) << 8;
1057 16796           lc = s->sym_buf[sx++];
1058 16796 100         if (dist == 0) {
1059 16179 100         send_code(s, lc, ltree); /* send a literal byte */
1060             Tracecv(isgraph(lc), (stderr," '%c' ", lc));
1061             } else {
1062             /* Here, lc is the match length - MIN_MATCH */
1063 617           code = _length_code[lc];
1064 617 100         send_code(s, code+LITERALS+1, ltree); /* send the length code */
1065 617           extra = extra_lbits[code];
1066 617 100         if (extra != 0) {
1067 115           lc -= base_length[code];
1068 115 100         send_bits(s, lc, extra); /* send the extra length bits */
1069             }
1070 617           dist--; /* dist is now the match distance - 1 */
1071 617 100         code = d_code(dist);
1072             Assert (code < D_CODES, "bad d_code");
1073              
1074 617 100         send_code(s, code, dtree); /* send the distance code */
1075 617           extra = extra_dbits[code];
1076 617 100         if (extra != 0) {
1077 490           dist -= (unsigned)base_dist[code];
1078 490 100         send_bits(s, dist, extra); /* send the extra distance bits */
1079             }
1080             } /* literal or match pair ? */
1081              
1082             /* Check that the overlay between pending_buf and sym_buf is ok: */
1083             Assert(s->pending < s->lit_bufsize + sx, "pendingBuf overflow");
1084              
1085 16796 100         } while (sx < s->sym_next);
1086              
1087 214 100         send_code(s, END_BLOCK, ltree);
1088 214           }
1089              
1090             /* ===========================================================================
1091             * Check if the data type is TEXT or BINARY, using the following algorithm:
1092             * - TEXT if the two conditions below are satisfied:
1093             * a) There are no non-portable control characters belonging to the
1094             * "block list" (0..6, 14..25, 28..31).
1095             * b) There is at least one printable character belonging to the
1096             * "allow list" (9 {TAB}, 10 {LF}, 13 {CR}, 32..255).
1097             * - BINARY otherwise.
1098             * - The following partially-portable control characters form a
1099             * "gray list" that is ignored in this detection algorithm:
1100             * (7 {BEL}, 8 {BS}, 11 {VT}, 12 {FF}, 26 {SUB}, 27 {ESC}).
1101             * IN assertion: the fields Freq of dyn_ltree are set.
1102             */
1103 214           local int detect_data_type(s)
1104             deflate_state *s;
1105             {
1106             /* block_mask is the bit mask of block-listed bytes
1107             * set bits 0..6, 14..25, and 28..31
1108             * 0xf3ffc07f = binary 11110011111111111100000001111111
1109             */
1110 214           unsigned long block_mask = 0xf3ffc07fUL;
1111             int n;
1112              
1113             /* Check for non-textual ("block-listed") bytes. */
1114 1436 100         for (n = 0; n <= 31; n++, block_mask >>= 1)
1115 1398 100         if ((block_mask & 1) && (s->dyn_ltree[n].Freq != 0))
    100          
1116 176           return Z_BINARY;
1117              
1118             /* Check for textual ("allow-listed") bytes. */
1119 38 50         if (s->dyn_ltree[9].Freq != 0 || s->dyn_ltree[10].Freq != 0
    100          
1120 23 50         || s->dyn_ltree[13].Freq != 0)
1121 15           return Z_TEXT;
1122 537 100         for (n = 32; n < LITERALS; n++)
1123 535 100         if (s->dyn_ltree[n].Freq != 0)
1124 21           return Z_TEXT;
1125              
1126             /* There are no "block-listed" or "allow-listed" bytes:
1127             * this stream either is empty or has tolerated ("gray-listed") bytes only.
1128             */
1129 2           return Z_BINARY;
1130             }
1131              
1132             /* ===========================================================================
1133             * Reverse the first len bits of a code, using straightforward code (a faster
1134             * method would use a table)
1135             * IN assertion: 1 <= len <= 15
1136             */
1137 9846           local unsigned bi_reverse(code, len)
1138             unsigned code; /* the value to invert */
1139             int len; /* its bit length */
1140             {
1141 9846           register unsigned res = 0;
1142             do {
1143 49288           res |= code & 1;
1144 49288           code >>= 1, res <<= 1;
1145 49288 100         } while (--len > 0);
1146 9846           return res >> 1;
1147             }
1148              
1149             /* ===========================================================================
1150             * Flush the bit buffer, keeping at most 7 bits in it.
1151             */
1152 645           local void bi_flush(s)
1153             deflate_state *s;
1154             {
1155 645 50         if (s->bi_valid == 16) {
1156 0           put_short(s, s->bi_buf);
1157 0           s->bi_buf = 0;
1158 0           s->bi_valid = 0;
1159 645 50         } else if (s->bi_valid >= 8) {
1160 0           put_byte(s, (Byte)s->bi_buf);
1161 0           s->bi_buf >>= 8;
1162 0           s->bi_valid -= 8;
1163             }
1164 645           }
1165              
1166             /* ===========================================================================
1167             * Flush the bit buffer and align the output on a byte boundary
1168             */
1169 214           local void bi_windup(s)
1170             deflate_state *s;
1171             {
1172 214 100         if (s->bi_valid > 8) {
1173 91           put_short(s, s->bi_buf);
1174 123 50         } else if (s->bi_valid > 0) {
1175 123           put_byte(s, (Byte)s->bi_buf);
1176             }
1177 214           s->bi_buf = 0;
1178 214           s->bi_valid = 0;
1179             #ifdef ZLIB_DEBUG
1180             s->bits_sent = (s->bits_sent+7) & ~7;
1181             #endif
1182 214           }