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Diffstat (limited to 'libraries/irrlicht-1.8/source/Irrlicht/zlib/trees.c')
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diff --git a/libraries/irrlicht-1.8/source/Irrlicht/zlib/trees.c b/libraries/irrlicht-1.8/source/Irrlicht/zlib/trees.c new file mode 100644 index 0000000..8ac7a90 --- /dev/null +++ b/libraries/irrlicht-1.8/source/Irrlicht/zlib/trees.c | |||
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1 | /* trees.c -- output deflated data using Huffman coding | ||
2 | * Copyright (C) 1995-2012 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 DEBUG | ||
40 | # include <ctype.h> | ||
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 static_tree_desc static_l_desc = | ||
126 | {static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS}; | ||
127 | |||
128 | local static_tree_desc static_d_desc = | ||
129 | {static_dtree, extra_dbits, 0, D_CODES, MAX_BITS}; | ||
130 | |||
131 | local 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, ct_data *ltree, | ||
150 | ct_data *dtree)); | ||
151 | local int detect_data_type OF((deflate_state *s)); | ||
152 | local unsigned bi_reverse OF((unsigned value, int length)); | ||
153 | local void bi_windup OF((deflate_state *s)); | ||
154 | local void bi_flush OF((deflate_state *s)); | ||
155 | local void copy_block OF((deflate_state *s, charf *buf, unsigned len, | ||
156 | int header)); | ||
157 | |||
158 | #ifdef GEN_TREES_H | ||
159 | local void gen_trees_header OF((void)); | ||
160 | #endif | ||
161 | |||
162 | #ifndef DEBUG | ||
163 | # define send_code(s, c, tree) send_bits(s, tree[c].Code, tree[c].Len) | ||
164 | /* Send a code of the given tree. c and tree must not have side effects */ | ||
165 | |||
166 | #else /* DEBUG */ | ||
167 | # define send_code(s, c, tree) \ | ||
168 | { if (z_verbose>2) fprintf(stderr,"\ncd %3d ",(c)); \ | ||
169 | send_bits(s, tree[c].Code, tree[c].Len); } | ||
170 | #endif | ||
171 | |||
172 | /* =========================================================================== | ||
173 | * Output a short LSB first on the stream. | ||
174 | * IN assertion: there is enough room in pendingBuf. | ||
175 | */ | ||
176 | #define put_short(s, w) { \ | ||
177 | put_byte(s, (uch)((w) & 0xff)); \ | ||
178 | put_byte(s, (uch)((ush)(w) >> 8)); \ | ||
179 | } | ||
180 | |||
181 | /* =========================================================================== | ||
182 | * Send a value on a given number of bits. | ||
183 | * IN assertion: length <= 16 and value fits in length bits. | ||
184 | */ | ||
185 | #ifdef DEBUG | ||
186 | local void send_bits OF((deflate_state *s, int value, int length)); | ||
187 | |||
188 | local void send_bits(s, value, length) | ||
189 | deflate_state *s; | ||
190 | int value; /* value to send */ | ||
191 | int length; /* number of bits */ | ||
192 | { | ||
193 | Tracevv((stderr," l %2d v %4x ", length, value)); | ||
194 | Assert(length > 0 && length <= 15, "invalid length"); | ||
195 | s->bits_sent += (ulg)length; | ||
196 | |||
197 | /* If not enough room in bi_buf, use (valid) bits from bi_buf and | ||
198 | * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid)) | ||
199 | * unused bits in value. | ||
200 | */ | ||
201 | if (s->bi_valid > (int)Buf_size - length) { | ||
202 | s->bi_buf |= (ush)value << s->bi_valid; | ||
203 | put_short(s, s->bi_buf); | ||
204 | s->bi_buf = (ush)value >> (Buf_size - s->bi_valid); | ||
205 | s->bi_valid += length - Buf_size; | ||
206 | } else { | ||
207 | s->bi_buf |= (ush)value << s->bi_valid; | ||
208 | s->bi_valid += length; | ||
209 | } | ||
210 | } | ||
211 | #else /* !DEBUG */ | ||
212 | |||
213 | #define send_bits(s, value, length) \ | ||
214 | { int len = length;\ | ||
215 | if (s->bi_valid > (int)Buf_size - len) {\ | ||
216 | int val = value;\ | ||
217 | s->bi_buf |= (ush)val << s->bi_valid;\ | ||
218 | put_short(s, s->bi_buf);\ | ||
219 | s->bi_buf = (ush)val >> (Buf_size - s->bi_valid);\ | ||
220 | s->bi_valid += len - Buf_size;\ | ||
221 | } else {\ | ||
222 | s->bi_buf |= (ush)(value) << s->bi_valid;\ | ||
223 | s->bi_valid += len;\ | ||
224 | }\ | ||
225 | } | ||
226 | #endif /* DEBUG */ | ||
227 | |||
228 | |||
229 | /* the arguments must not have side effects */ | ||
230 | |||
231 | /* =========================================================================== | ||
232 | * Initialize the various 'constant' tables. | ||
233 | */ | ||
234 | local void tr_static_init() | ||
235 | { | ||
236 | #if defined(GEN_TREES_H) || !defined(STDC) | ||
237 | static int static_init_done = 0; | ||
238 | int n; /* iterates over tree elements */ | ||
239 | int bits; /* bit counter */ | ||
240 | int length; /* length value */ | ||
241 | int code; /* code value */ | ||
242 | int dist; /* distance index */ | ||
243 | ush bl_count[MAX_BITS+1]; | ||
244 | /* number of codes at each bit length for an optimal tree */ | ||
245 | |||
246 | if (static_init_done) return; | ||
247 | |||
248 | /* For some embedded targets, global variables are not initialized: */ | ||
249 | #ifdef NO_INIT_GLOBAL_POINTERS | ||
250 | static_l_desc.static_tree = static_ltree; | ||
251 | static_l_desc.extra_bits = extra_lbits; | ||
252 | static_d_desc.static_tree = static_dtree; | ||
253 | static_d_desc.extra_bits = extra_dbits; | ||
254 | static_bl_desc.extra_bits = extra_blbits; | ||
255 | #endif | ||
256 | |||
257 | /* Initialize the mapping length (0..255) -> length code (0..28) */ | ||
258 | length = 0; | ||
259 | for (code = 0; code < LENGTH_CODES-1; code++) { | ||
260 | base_length[code] = length; | ||
261 | for (n = 0; n < (1<<extra_lbits[code]); n++) { | ||
262 | _length_code[length++] = (uch)code; | ||
263 | } | ||
264 | } | ||
265 | Assert (length == 256, "tr_static_init: length != 256"); | ||
266 | /* Note that the length 255 (match length 258) can be represented | ||
267 | * in two different ways: code 284 + 5 bits or code 285, so we | ||
268 | * overwrite length_code[255] to use the best encoding: | ||
269 | */ | ||
270 | _length_code[length-1] = (uch)code; | ||
271 | |||
272 | /* Initialize the mapping dist (0..32K) -> dist code (0..29) */ | ||
273 | dist = 0; | ||
274 | for (code = 0 ; code < 16; code++) { | ||
275 | base_dist[code] = dist; | ||
276 | for (n = 0; n < (1<<extra_dbits[code]); n++) { | ||
277 | _dist_code[dist++] = (uch)code; | ||
278 | } | ||
279 | } | ||
280 | Assert (dist == 256, "tr_static_init: dist != 256"); | ||
281 | dist >>= 7; /* from now on, all distances are divided by 128 */ | ||
282 | for ( ; code < D_CODES; code++) { | ||
283 | base_dist[code] = dist << 7; | ||
284 | for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) { | ||
285 | _dist_code[256 + dist++] = (uch)code; | ||
286 | } | ||
287 | } | ||
288 | Assert (dist == 256, "tr_static_init: 256+dist != 512"); | ||
289 | |||
290 | /* Construct the codes of the static literal tree */ | ||
291 | for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0; | ||
292 | n = 0; | ||
293 | while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++; | ||
294 | while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++; | ||
295 | while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++; | ||
296 | while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++; | ||
297 | /* Codes 286 and 287 do not exist, but we must include them in the | ||
298 | * tree construction to get a canonical Huffman tree (longest code | ||
299 | * all ones) | ||
300 | */ | ||
301 | gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count); | ||
302 | |||
303 | /* The static distance tree is trivial: */ | ||
304 | for (n = 0; n < D_CODES; n++) { | ||
305 | static_dtree[n].Len = 5; | ||
306 | static_dtree[n].Code = bi_reverse((unsigned)n, 5); | ||
307 | } | ||
308 | static_init_done = 1; | ||
309 | |||
310 | # ifdef GEN_TREES_H | ||
311 | gen_trees_header(); | ||
312 | # endif | ||
313 | #endif /* defined(GEN_TREES_H) || !defined(STDC) */ | ||
314 | } | ||
315 | |||
316 | /* =========================================================================== | ||
317 | * Genererate the file trees.h describing the static trees. | ||
318 | */ | ||
319 | #ifdef GEN_TREES_H | ||
320 | # ifndef DEBUG | ||
321 | # include <stdio.h> | ||
322 | # endif | ||
323 | |||
324 | # define SEPARATOR(i, last, width) \ | ||
325 | ((i) == (last)? "\n};\n\n" : \ | ||
326 | ((i) % (width) == (width)-1 ? ",\n" : ", ")) | ||
327 | |||
328 | void gen_trees_header() | ||
329 | { | ||
330 | FILE *header = fopen("trees.h", "w"); | ||
331 | int i; | ||
332 | |||
333 | Assert (header != NULL, "Can't open trees.h"); | ||
334 | fprintf(header, | ||
335 | "/* header created automatically with -DGEN_TREES_H */\n\n"); | ||
336 | |||
337 | fprintf(header, "local const ct_data static_ltree[L_CODES+2] = {\n"); | ||
338 | for (i = 0; i < L_CODES+2; i++) { | ||
339 | fprintf(header, "{{%3u},{%3u}}%s", static_ltree[i].Code, | ||
340 | static_ltree[i].Len, SEPARATOR(i, L_CODES+1, 5)); | ||
341 | } | ||
342 | |||
343 | fprintf(header, "local const ct_data static_dtree[D_CODES] = {\n"); | ||
344 | for (i = 0; i < D_CODES; i++) { | ||
345 | fprintf(header, "{{%2u},{%2u}}%s", static_dtree[i].Code, | ||
346 | static_dtree[i].Len, SEPARATOR(i, D_CODES-1, 5)); | ||
347 | } | ||
348 | |||
349 | fprintf(header, "const uch ZLIB_INTERNAL _dist_code[DIST_CODE_LEN] = {\n"); | ||
350 | for (i = 0; i < DIST_CODE_LEN; i++) { | ||
351 | fprintf(header, "%2u%s", _dist_code[i], | ||
352 | SEPARATOR(i, DIST_CODE_LEN-1, 20)); | ||
353 | } | ||
354 | |||
355 | fprintf(header, | ||
356 | "const uch ZLIB_INTERNAL _length_code[MAX_MATCH-MIN_MATCH+1]= {\n"); | ||
357 | for (i = 0; i < MAX_MATCH-MIN_MATCH+1; i++) { | ||
358 | fprintf(header, "%2u%s", _length_code[i], | ||
359 | SEPARATOR(i, MAX_MATCH-MIN_MATCH, 20)); | ||
360 | } | ||
361 | |||
362 | fprintf(header, "local const int base_length[LENGTH_CODES] = {\n"); | ||
363 | for (i = 0; i < LENGTH_CODES; i++) { | ||
364 | fprintf(header, "%1u%s", base_length[i], | ||
365 | SEPARATOR(i, LENGTH_CODES-1, 20)); | ||
366 | } | ||
367 | |||
368 | fprintf(header, "local const int base_dist[D_CODES] = {\n"); | ||
369 | for (i = 0; i < D_CODES; i++) { | ||
370 | fprintf(header, "%5u%s", base_dist[i], | ||
371 | SEPARATOR(i, D_CODES-1, 10)); | ||
372 | } | ||
373 | |||
374 | fclose(header); | ||
375 | } | ||
376 | #endif /* GEN_TREES_H */ | ||
377 | |||
378 | /* =========================================================================== | ||
379 | * Initialize the tree data structures for a new zlib stream. | ||
380 | */ | ||
381 | void ZLIB_INTERNAL _tr_init(s) | ||
382 | deflate_state *s; | ||
383 | { | ||
384 | tr_static_init(); | ||
385 | |||
386 | s->l_desc.dyn_tree = s->dyn_ltree; | ||
387 | s->l_desc.stat_desc = &static_l_desc; | ||
388 | |||
389 | s->d_desc.dyn_tree = s->dyn_dtree; | ||
390 | s->d_desc.stat_desc = &static_d_desc; | ||
391 | |||
392 | s->bl_desc.dyn_tree = s->bl_tree; | ||
393 | s->bl_desc.stat_desc = &static_bl_desc; | ||
394 | |||
395 | s->bi_buf = 0; | ||
396 | s->bi_valid = 0; | ||
397 | #ifdef DEBUG | ||
398 | s->compressed_len = 0L; | ||
399 | s->bits_sent = 0L; | ||
400 | #endif | ||
401 | |||
402 | /* Initialize the first block of the first file: */ | ||
403 | init_block(s); | ||
404 | } | ||
405 | |||
406 | /* =========================================================================== | ||
407 | * Initialize a new block. | ||
408 | */ | ||
409 | local void init_block(s) | ||
410 | deflate_state *s; | ||
411 | { | ||
412 | int n; /* iterates over tree elements */ | ||
413 | |||
414 | /* Initialize the trees. */ | ||
415 | for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0; | ||
416 | for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0; | ||
417 | for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0; | ||
418 | |||
419 | s->dyn_ltree[END_BLOCK].Freq = 1; | ||
420 | s->opt_len = s->static_len = 0L; | ||
421 | s->last_lit = s->matches = 0; | ||
422 | } | ||
423 | |||
424 | #define SMALLEST 1 | ||
425 | /* Index within the heap array of least frequent node in the Huffman tree */ | ||
426 | |||
427 | |||
428 | /* =========================================================================== | ||
429 | * Remove the smallest element from the heap and recreate the heap with | ||
430 | * one less element. Updates heap and heap_len. | ||
431 | */ | ||
432 | #define pqremove(s, tree, top) \ | ||
433 | {\ | ||
434 | top = s->heap[SMALLEST]; \ | ||
435 | s->heap[SMALLEST] = s->heap[s->heap_len--]; \ | ||
436 | pqdownheap(s, tree, SMALLEST); \ | ||
437 | } | ||
438 | |||
439 | /* =========================================================================== | ||
440 | * Compares to subtrees, using the tree depth as tie breaker when | ||
441 | * the subtrees have equal frequency. This minimizes the worst case length. | ||
442 | */ | ||
443 | #define smaller(tree, n, m, depth) \ | ||
444 | (tree[n].Freq < tree[m].Freq || \ | ||
445 | (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m])) | ||
446 | |||
447 | /* =========================================================================== | ||
448 | * Restore the heap property by moving down the tree starting at node k, | ||
449 | * exchanging a node with the smallest of its two sons if necessary, stopping | ||
450 | * when the heap property is re-established (each father smaller than its | ||
451 | * two sons). | ||
452 | */ | ||
453 | local void pqdownheap(s, tree, k) | ||
454 | deflate_state *s; | ||
455 | ct_data *tree; /* the tree to restore */ | ||
456 | int k; /* node to move down */ | ||
457 | { | ||
458 | int v = s->heap[k]; | ||
459 | int j = k << 1; /* left son of k */ | ||
460 | while (j <= s->heap_len) { | ||
461 | /* Set j to the smallest of the two sons: */ | ||
462 | if (j < s->heap_len && | ||
463 | smaller(tree, s->heap[j+1], s->heap[j], s->depth)) { | ||
464 | j++; | ||
465 | } | ||
466 | /* Exit if v is smaller than both sons */ | ||
467 | if (smaller(tree, v, s->heap[j], s->depth)) break; | ||
468 | |||
469 | /* Exchange v with the smallest son */ | ||
470 | s->heap[k] = s->heap[j]; k = j; | ||
471 | |||
472 | /* And continue down the tree, setting j to the left son of k */ | ||
473 | j <<= 1; | ||
474 | } | ||
475 | s->heap[k] = v; | ||
476 | } | ||
477 | |||
478 | /* =========================================================================== | ||
479 | * Compute the optimal bit lengths for a tree and update the total bit length | ||
480 | * for the current block. | ||
481 | * IN assertion: the fields freq and dad are set, heap[heap_max] and | ||
482 | * above are the tree nodes sorted by increasing frequency. | ||
483 | * OUT assertions: the field len is set to the optimal bit length, the | ||
484 | * array bl_count contains the frequencies for each bit length. | ||
485 | * The length opt_len is updated; static_len is also updated if stree is | ||
486 | * not null. | ||
487 | */ | ||
488 | local void gen_bitlen(s, desc) | ||
489 | deflate_state *s; | ||
490 | tree_desc *desc; /* the tree descriptor */ | ||
491 | { | ||
492 | ct_data *tree = desc->dyn_tree; | ||
493 | int max_code = desc->max_code; | ||
494 | const ct_data *stree = desc->stat_desc->static_tree; | ||
495 | const intf *extra = desc->stat_desc->extra_bits; | ||
496 | int base = desc->stat_desc->extra_base; | ||
497 | int max_length = desc->stat_desc->max_length; | ||
498 | int h; /* heap index */ | ||
499 | int n, m; /* iterate over the tree elements */ | ||
500 | int bits; /* bit length */ | ||
501 | int xbits; /* extra bits */ | ||
502 | ush f; /* frequency */ | ||
503 | int overflow = 0; /* number of elements with bit length too large */ | ||
504 | |||
505 | for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0; | ||
506 | |||
507 | /* In a first pass, compute the optimal bit lengths (which may | ||
508 | * overflow in the case of the bit length tree). | ||
509 | */ | ||
510 | tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */ | ||
511 | |||
512 | for (h = s->heap_max+1; h < HEAP_SIZE; h++) { | ||
513 | n = s->heap[h]; | ||
514 | bits = tree[tree[n].Dad].Len + 1; | ||
515 | if (bits > max_length) bits = max_length, overflow++; | ||
516 | tree[n].Len = (ush)bits; | ||
517 | /* We overwrite tree[n].Dad which is no longer needed */ | ||
518 | |||
519 | if (n > max_code) continue; /* not a leaf node */ | ||
520 | |||
521 | s->bl_count[bits]++; | ||
522 | xbits = 0; | ||
523 | if (n >= base) xbits = extra[n-base]; | ||
524 | f = tree[n].Freq; | ||
525 | s->opt_len += (ulg)f * (bits + xbits); | ||
526 | if (stree) s->static_len += (ulg)f * (stree[n].Len + xbits); | ||
527 | } | ||
528 | if (overflow == 0) return; | ||
529 | |||
530 | Trace((stderr,"\nbit length overflow\n")); | ||
531 | /* This happens for example on obj2 and pic of the Calgary corpus */ | ||
532 | |||
533 | /* Find the first bit length which could increase: */ | ||
534 | do { | ||
535 | bits = max_length-1; | ||
536 | while (s->bl_count[bits] == 0) bits--; | ||
537 | s->bl_count[bits]--; /* move one leaf down the tree */ | ||
538 | s->bl_count[bits+1] += 2; /* move one overflow item as its brother */ | ||
539 | s->bl_count[max_length]--; | ||
540 | /* The brother of the overflow item also moves one step up, | ||
541 | * but this does not affect bl_count[max_length] | ||
542 | */ | ||
543 | overflow -= 2; | ||
544 | } while (overflow > 0); | ||
545 | |||
546 | /* Now recompute all bit lengths, scanning in increasing frequency. | ||
547 | * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all | ||
548 | * lengths instead of fixing only the wrong ones. This idea is taken | ||
549 | * from 'ar' written by Haruhiko Okumura.) | ||
550 | */ | ||
551 | for (bits = max_length; bits != 0; bits--) { | ||
552 | n = s->bl_count[bits]; | ||
553 | while (n != 0) { | ||
554 | m = s->heap[--h]; | ||
555 | if (m > max_code) continue; | ||
556 | if ((unsigned) tree[m].Len != (unsigned) bits) { | ||
557 | Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits)); | ||
558 | s->opt_len += ((long)bits - (long)tree[m].Len) | ||
559 | *(long)tree[m].Freq; | ||
560 | tree[m].Len = (ush)bits; | ||
561 | } | ||
562 | n--; | ||
563 | } | ||
564 | } | ||
565 | } | ||
566 | |||
567 | /* =========================================================================== | ||
568 | * Generate the codes for a given tree and bit counts (which need not be | ||
569 | * optimal). | ||
570 | * IN assertion: the array bl_count contains the bit length statistics for | ||
571 | * the given tree and the field len is set for all tree elements. | ||
572 | * OUT assertion: the field code is set for all tree elements of non | ||
573 | * zero code length. | ||
574 | */ | ||
575 | local void gen_codes (tree, max_code, bl_count) | ||
576 | ct_data *tree; /* the tree to decorate */ | ||
577 | int max_code; /* largest code with non zero frequency */ | ||
578 | ushf *bl_count; /* number of codes at each bit length */ | ||
579 | { | ||
580 | ush next_code[MAX_BITS+1]; /* next code value for each bit length */ | ||
581 | ush code = 0; /* running code value */ | ||
582 | int bits; /* bit index */ | ||
583 | int n; /* code index */ | ||
584 | |||
585 | /* The distribution counts are first used to generate the code values | ||
586 | * without bit reversal. | ||
587 | */ | ||
588 | for (bits = 1; bits <= MAX_BITS; bits++) { | ||
589 | next_code[bits] = code = (code + bl_count[bits-1]) << 1; | ||
590 | } | ||
591 | /* Check that the bit counts in bl_count are consistent. The last code | ||
592 | * must be all ones. | ||
593 | */ | ||
594 | Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1, | ||
595 | "inconsistent bit counts"); | ||
596 | Tracev((stderr,"\ngen_codes: max_code %d ", max_code)); | ||
597 | |||
598 | for (n = 0; n <= max_code; n++) { | ||
599 | int len = tree[n].Len; | ||
600 | if (len == 0) continue; | ||
601 | /* Now reverse the bits */ | ||
602 | tree[n].Code = bi_reverse(next_code[len]++, len); | ||
603 | |||
604 | Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ", | ||
605 | n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1)); | ||
606 | } | ||
607 | } | ||
608 | |||
609 | /* =========================================================================== | ||
610 | * Construct one Huffman tree and assigns the code bit strings and lengths. | ||
611 | * Update the total bit length for the current block. | ||
612 | * IN assertion: the field freq is set for all tree elements. | ||
613 | * OUT assertions: the fields len and code are set to the optimal bit length | ||
614 | * and corresponding code. The length opt_len is updated; static_len is | ||
615 | * also updated if stree is not null. The field max_code is set. | ||
616 | */ | ||
617 | local void build_tree(s, desc) | ||
618 | deflate_state *s; | ||
619 | tree_desc *desc; /* the tree descriptor */ | ||
620 | { | ||
621 | ct_data *tree = desc->dyn_tree; | ||
622 | const ct_data *stree = desc->stat_desc->static_tree; | ||
623 | int elems = desc->stat_desc->elems; | ||
624 | int n, m; /* iterate over heap elements */ | ||
625 | int max_code = -1; /* largest code with non zero frequency */ | ||
626 | int node; /* new node being created */ | ||
627 | |||
628 | /* Construct the initial heap, with least frequent element in | ||
629 | * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1]. | ||
630 | * heap[0] is not used. | ||
631 | */ | ||
632 | s->heap_len = 0, s->heap_max = HEAP_SIZE; | ||
633 | |||
634 | for (n = 0; n < elems; n++) { | ||
635 | if (tree[n].Freq != 0) { | ||
636 | s->heap[++(s->heap_len)] = max_code = n; | ||
637 | s->depth[n] = 0; | ||
638 | } else { | ||
639 | tree[n].Len = 0; | ||
640 | } | ||
641 | } | ||
642 | |||
643 | /* The pkzip format requires that at least one distance code exists, | ||
644 | * and that at least one bit should be sent even if there is only one | ||
645 | * possible code. So to avoid special checks later on we force at least | ||
646 | * two codes of non zero frequency. | ||
647 | */ | ||
648 | while (s->heap_len < 2) { | ||
649 | node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0); | ||
650 | tree[node].Freq = 1; | ||
651 | s->depth[node] = 0; | ||
652 | s->opt_len--; if (stree) s->static_len -= stree[node].Len; | ||
653 | /* node is 0 or 1 so it does not have extra bits */ | ||
654 | } | ||
655 | desc->max_code = max_code; | ||
656 | |||
657 | /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree, | ||
658 | * establish sub-heaps of increasing lengths: | ||
659 | */ | ||
660 | for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n); | ||
661 | |||
662 | /* Construct the Huffman tree by repeatedly combining the least two | ||
663 | * frequent nodes. | ||
664 | */ | ||
665 | node = elems; /* next internal node of the tree */ | ||
666 | do { | ||
667 | pqremove(s, tree, n); /* n = node of least frequency */ | ||
668 | m = s->heap[SMALLEST]; /* m = node of next least frequency */ | ||
669 | |||
670 | s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */ | ||
671 | s->heap[--(s->heap_max)] = m; | ||
672 | |||
673 | /* Create a new node father of n and m */ | ||
674 | tree[node].Freq = tree[n].Freq + tree[m].Freq; | ||
675 | s->depth[node] = (uch)((s->depth[n] >= s->depth[m] ? | ||
676 | s->depth[n] : s->depth[m]) + 1); | ||
677 | tree[n].Dad = tree[m].Dad = (ush)node; | ||
678 | #ifdef DUMP_BL_TREE | ||
679 | if (tree == s->bl_tree) { | ||
680 | fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)", | ||
681 | node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq); | ||
682 | } | ||
683 | #endif | ||
684 | /* and insert the new node in the heap */ | ||
685 | s->heap[SMALLEST] = node++; | ||
686 | pqdownheap(s, tree, SMALLEST); | ||
687 | |||
688 | } while (s->heap_len >= 2); | ||
689 | |||
690 | s->heap[--(s->heap_max)] = s->heap[SMALLEST]; | ||
691 | |||
692 | /* At this point, the fields freq and dad are set. We can now | ||
693 | * generate the bit lengths. | ||
694 | */ | ||
695 | gen_bitlen(s, (tree_desc *)desc); | ||
696 | |||
697 | /* The field len is now set, we can generate the bit codes */ | ||
698 | gen_codes ((ct_data *)tree, max_code, s->bl_count); | ||
699 | } | ||
700 | |||
701 | /* =========================================================================== | ||
702 | * Scan a literal or distance tree to determine the frequencies of the codes | ||
703 | * in the bit length tree. | ||
704 | */ | ||
705 | local void scan_tree (s, tree, max_code) | ||
706 | deflate_state *s; | ||
707 | ct_data *tree; /* the tree to be scanned */ | ||
708 | int max_code; /* and its largest code of non zero frequency */ | ||
709 | { | ||
710 | int n; /* iterates over all tree elements */ | ||
711 | int prevlen = -1; /* last emitted length */ | ||
712 | int curlen; /* length of current code */ | ||
713 | int nextlen = tree[0].Len; /* length of next code */ | ||
714 | int count = 0; /* repeat count of the current code */ | ||
715 | int max_count = 7; /* max repeat count */ | ||
716 | int min_count = 4; /* min repeat count */ | ||
717 | |||
718 | if (nextlen == 0) max_count = 138, min_count = 3; | ||
719 | tree[max_code+1].Len = (ush)0xffff; /* guard */ | ||
720 | |||
721 | for (n = 0; n <= max_code; n++) { | ||
722 | curlen = nextlen; nextlen = tree[n+1].Len; | ||
723 | if (++count < max_count && curlen == nextlen) { | ||
724 | continue; | ||
725 | } else if (count < min_count) { | ||
726 | s->bl_tree[curlen].Freq += count; | ||
727 | } else if (curlen != 0) { | ||
728 | if (curlen != prevlen) s->bl_tree[curlen].Freq++; | ||
729 | s->bl_tree[REP_3_6].Freq++; | ||
730 | } else if (count <= 10) { | ||
731 | s->bl_tree[REPZ_3_10].Freq++; | ||
732 | } else { | ||
733 | s->bl_tree[REPZ_11_138].Freq++; | ||
734 | } | ||
735 | count = 0; prevlen = curlen; | ||
736 | if (nextlen == 0) { | ||
737 | max_count = 138, min_count = 3; | ||
738 | } else if (curlen == nextlen) { | ||
739 | max_count = 6, min_count = 3; | ||
740 | } else { | ||
741 | max_count = 7, min_count = 4; | ||
742 | } | ||
743 | } | ||
744 | } | ||
745 | |||
746 | /* =========================================================================== | ||
747 | * Send a literal or distance tree in compressed form, using the codes in | ||
748 | * bl_tree. | ||
749 | */ | ||
750 | local void send_tree (s, tree, max_code) | ||
751 | deflate_state *s; | ||
752 | ct_data *tree; /* the tree to be scanned */ | ||
753 | int max_code; /* and its largest code of non zero frequency */ | ||
754 | { | ||
755 | int n; /* iterates over all tree elements */ | ||
756 | int prevlen = -1; /* last emitted length */ | ||
757 | int curlen; /* length of current code */ | ||
758 | int nextlen = tree[0].Len; /* length of next code */ | ||
759 | int count = 0; /* repeat count of the current code */ | ||
760 | int max_count = 7; /* max repeat count */ | ||
761 | int min_count = 4; /* min repeat count */ | ||
762 | |||
763 | /* tree[max_code+1].Len = -1; */ /* guard already set */ | ||
764 | if (nextlen == 0) max_count = 138, min_count = 3; | ||
765 | |||
766 | for (n = 0; n <= max_code; n++) { | ||
767 | curlen = nextlen; nextlen = tree[n+1].Len; | ||
768 | if (++count < max_count && curlen == nextlen) { | ||
769 | continue; | ||
770 | } else if (count < min_count) { | ||
771 | do { send_code(s, curlen, s->bl_tree); } while (--count != 0); | ||
772 | |||
773 | } else if (curlen != 0) { | ||
774 | if (curlen != prevlen) { | ||
775 | send_code(s, curlen, s->bl_tree); count--; | ||
776 | } | ||
777 | Assert(count >= 3 && count <= 6, " 3_6?"); | ||
778 | send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2); | ||
779 | |||
780 | } else if (count <= 10) { | ||
781 | send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3); | ||
782 | |||
783 | } else { | ||
784 | send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7); | ||
785 | } | ||
786 | count = 0; prevlen = curlen; | ||
787 | if (nextlen == 0) { | ||
788 | max_count = 138, min_count = 3; | ||
789 | } else if (curlen == nextlen) { | ||
790 | max_count = 6, min_count = 3; | ||
791 | } else { | ||
792 | max_count = 7, min_count = 4; | ||
793 | } | ||
794 | } | ||
795 | } | ||
796 | |||
797 | /* =========================================================================== | ||
798 | * Construct the Huffman tree for the bit lengths and return the index in | ||
799 | * bl_order of the last bit length code to send. | ||
800 | */ | ||
801 | local int build_bl_tree(s) | ||
802 | deflate_state *s; | ||
803 | { | ||
804 | int max_blindex; /* index of last bit length code of non zero freq */ | ||
805 | |||
806 | /* Determine the bit length frequencies for literal and distance trees */ | ||
807 | scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code); | ||
808 | scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code); | ||
809 | |||
810 | /* Build the bit length tree: */ | ||
811 | build_tree(s, (tree_desc *)(&(s->bl_desc))); | ||
812 | /* opt_len now includes the length of the tree representations, except | ||
813 | * the lengths of the bit lengths codes and the 5+5+4 bits for the counts. | ||
814 | */ | ||
815 | |||
816 | /* Determine the number of bit length codes to send. The pkzip format | ||
817 | * requires that at least 4 bit length codes be sent. (appnote.txt says | ||
818 | * 3 but the actual value used is 4.) | ||
819 | */ | ||
820 | for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) { | ||
821 | if (s->bl_tree[bl_order[max_blindex]].Len != 0) break; | ||
822 | } | ||
823 | /* Update opt_len to include the bit length tree and counts */ | ||
824 | s->opt_len += 3*(max_blindex+1) + 5+5+4; | ||
825 | Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld", | ||
826 | s->opt_len, s->static_len)); | ||
827 | |||
828 | return max_blindex; | ||
829 | } | ||
830 | |||
831 | /* =========================================================================== | ||
832 | * Send the header for a block using dynamic Huffman trees: the counts, the | ||
833 | * lengths of the bit length codes, the literal tree and the distance tree. | ||
834 | * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4. | ||
835 | */ | ||
836 | local void send_all_trees(s, lcodes, dcodes, blcodes) | ||
837 | deflate_state *s; | ||
838 | int lcodes, dcodes, blcodes; /* number of codes for each tree */ | ||
839 | { | ||
840 | int rank; /* index in bl_order */ | ||
841 | |||
842 | Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes"); | ||
843 | Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES, | ||
844 | "too many codes"); | ||
845 | Tracev((stderr, "\nbl counts: ")); | ||
846 | send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */ | ||
847 | send_bits(s, dcodes-1, 5); | ||
848 | send_bits(s, blcodes-4, 4); /* not -3 as stated in appnote.txt */ | ||
849 | for (rank = 0; rank < blcodes; rank++) { | ||
850 | Tracev((stderr, "\nbl code %2d ", bl_order[rank])); | ||
851 | send_bits(s, s->bl_tree[bl_order[rank]].Len, 3); | ||
852 | } | ||
853 | Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent)); | ||
854 | |||
855 | send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */ | ||
856 | Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent)); | ||
857 | |||
858 | send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */ | ||
859 | Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent)); | ||
860 | } | ||
861 | |||
862 | /* =========================================================================== | ||
863 | * Send a stored block | ||
864 | */ | ||
865 | void ZLIB_INTERNAL _tr_stored_block(s, buf, stored_len, last) | ||
866 | deflate_state *s; | ||
867 | charf *buf; /* input block */ | ||
868 | ulg stored_len; /* length of input block */ | ||
869 | int last; /* one if this is the last block for a file */ | ||
870 | { | ||
871 | send_bits(s, (STORED_BLOCK<<1)+last, 3); /* send block type */ | ||
872 | #ifdef DEBUG | ||
873 | s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L; | ||
874 | s->compressed_len += (stored_len + 4) << 3; | ||
875 | #endif | ||
876 | copy_block(s, buf, (unsigned)stored_len, 1); /* with header */ | ||
877 | } | ||
878 | |||
879 | /* =========================================================================== | ||
880 | * Flush the bits in the bit buffer to pending output (leaves at most 7 bits) | ||
881 | */ | ||
882 | void ZLIB_INTERNAL _tr_flush_bits(s) | ||
883 | deflate_state *s; | ||
884 | { | ||
885 | bi_flush(s); | ||
886 | } | ||
887 | |||
888 | /* =========================================================================== | ||
889 | * Send one empty static block to give enough lookahead for inflate. | ||
890 | * This takes 10 bits, of which 7 may remain in the bit buffer. | ||
891 | */ | ||
892 | void ZLIB_INTERNAL _tr_align(s) | ||
893 | deflate_state *s; | ||
894 | { | ||
895 | send_bits(s, STATIC_TREES<<1, 3); | ||
896 | send_code(s, END_BLOCK, static_ltree); | ||
897 | #ifdef DEBUG | ||
898 | s->compressed_len += 10L; /* 3 for block type, 7 for EOB */ | ||
899 | #endif | ||
900 | bi_flush(s); | ||
901 | } | ||
902 | |||
903 | /* =========================================================================== | ||
904 | * Determine the best encoding for the current block: dynamic trees, static | ||
905 | * trees or store, and output the encoded block to the zip file. | ||
906 | */ | ||
907 | void ZLIB_INTERNAL _tr_flush_block(s, buf, stored_len, last) | ||
908 | deflate_state *s; | ||
909 | charf *buf; /* input block, or NULL if too old */ | ||
910 | ulg stored_len; /* length of input block */ | ||
911 | int last; /* one if this is the last block for a file */ | ||
912 | { | ||
913 | ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */ | ||
914 | int max_blindex = 0; /* index of last bit length code of non zero freq */ | ||
915 | |||
916 | /* Build the Huffman trees unless a stored block is forced */ | ||
917 | if (s->level > 0) { | ||
918 | |||
919 | /* Check if the file is binary or text */ | ||
920 | if (s->strm->data_type == Z_UNKNOWN) | ||
921 | s->strm->data_type = detect_data_type(s); | ||
922 | |||
923 | /* Construct the literal and distance trees */ | ||
924 | build_tree(s, (tree_desc *)(&(s->l_desc))); | ||
925 | Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len, | ||
926 | s->static_len)); | ||
927 | |||
928 | build_tree(s, (tree_desc *)(&(s->d_desc))); | ||
929 | Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len, | ||
930 | s->static_len)); | ||
931 | /* At this point, opt_len and static_len are the total bit lengths of | ||
932 | * the compressed block data, excluding the tree representations. | ||
933 | */ | ||
934 | |||
935 | /* Build the bit length tree for the above two trees, and get the index | ||
936 | * in bl_order of the last bit length code to send. | ||
937 | */ | ||
938 | max_blindex = build_bl_tree(s); | ||
939 | |||
940 | /* Determine the best encoding. Compute the block lengths in bytes. */ | ||
941 | opt_lenb = (s->opt_len+3+7)>>3; | ||
942 | static_lenb = (s->static_len+3+7)>>3; | ||
943 | |||
944 | Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ", | ||
945 | opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len, | ||
946 | s->last_lit)); | ||
947 | |||
948 | if (static_lenb <= opt_lenb) opt_lenb = static_lenb; | ||
949 | |||
950 | } else { | ||
951 | Assert(buf != (char*)0, "lost buf"); | ||
952 | opt_lenb = static_lenb = stored_len + 5; /* force a stored block */ | ||
953 | } | ||
954 | |||
955 | #ifdef FORCE_STORED | ||
956 | if (buf != (char*)0) { /* force stored block */ | ||
957 | #else | ||
958 | if (stored_len+4 <= opt_lenb && buf != (char*)0) { | ||
959 | /* 4: two words for the lengths */ | ||
960 | #endif | ||
961 | /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE. | ||
962 | * Otherwise we can't have processed more than WSIZE input bytes since | ||
963 | * the last block flush, because compression would have been | ||
964 | * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to | ||
965 | * transform a block into a stored block. | ||
966 | */ | ||
967 | _tr_stored_block(s, buf, stored_len, last); | ||
968 | |||
969 | #ifdef FORCE_STATIC | ||
970 | } else if (static_lenb >= 0) { /* force static trees */ | ||
971 | #else | ||
972 | } else if (s->strategy == Z_FIXED || static_lenb == opt_lenb) { | ||
973 | #endif | ||
974 | send_bits(s, (STATIC_TREES<<1)+last, 3); | ||
975 | compress_block(s, (ct_data *)static_ltree, (ct_data *)static_dtree); | ||
976 | #ifdef DEBUG | ||
977 | s->compressed_len += 3 + s->static_len; | ||
978 | #endif | ||
979 | } else { | ||
980 | send_bits(s, (DYN_TREES<<1)+last, 3); | ||
981 | send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1, | ||
982 | max_blindex+1); | ||
983 | compress_block(s, (ct_data *)s->dyn_ltree, (ct_data *)s->dyn_dtree); | ||
984 | #ifdef DEBUG | ||
985 | s->compressed_len += 3 + s->opt_len; | ||
986 | #endif | ||
987 | } | ||
988 | Assert (s->compressed_len == s->bits_sent, "bad compressed size"); | ||
989 | /* The above check is made mod 2^32, for files larger than 512 MB | ||
990 | * and uLong implemented on 32 bits. | ||
991 | */ | ||
992 | init_block(s); | ||
993 | |||
994 | if (last) { | ||
995 | bi_windup(s); | ||
996 | #ifdef DEBUG | ||
997 | s->compressed_len += 7; /* align on byte boundary */ | ||
998 | #endif | ||
999 | } | ||
1000 | Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3, | ||
1001 | s->compressed_len-7*last)); | ||
1002 | } | ||
1003 | |||
1004 | /* =========================================================================== | ||
1005 | * Save the match info and tally the frequency counts. Return true if | ||
1006 | * the current block must be flushed. | ||
1007 | */ | ||
1008 | int ZLIB_INTERNAL _tr_tally (s, dist, lc) | ||
1009 | deflate_state *s; | ||
1010 | unsigned dist; /* distance of matched string */ | ||
1011 | unsigned lc; /* match length-MIN_MATCH or unmatched char (if dist==0) */ | ||
1012 | { | ||
1013 | s->d_buf[s->last_lit] = (ush)dist; | ||
1014 | s->l_buf[s->last_lit++] = (uch)lc; | ||
1015 | if (dist == 0) { | ||
1016 | /* lc is the unmatched char */ | ||
1017 | s->dyn_ltree[lc].Freq++; | ||
1018 | } else { | ||
1019 | s->matches++; | ||
1020 | /* Here, lc is the match length - MIN_MATCH */ | ||
1021 | dist--; /* dist = match distance - 1 */ | ||
1022 | Assert((ush)dist < (ush)MAX_DIST(s) && | ||
1023 | (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) && | ||
1024 | (ush)d_code(dist) < (ush)D_CODES, "_tr_tally: bad match"); | ||
1025 | |||
1026 | s->dyn_ltree[_length_code[lc]+LITERALS+1].Freq++; | ||
1027 | s->dyn_dtree[d_code(dist)].Freq++; | ||
1028 | } | ||
1029 | |||
1030 | #ifdef TRUNCATE_BLOCK | ||
1031 | /* Try to guess if it is profitable to stop the current block here */ | ||
1032 | if ((s->last_lit & 0x1fff) == 0 && s->level > 2) { | ||
1033 | /* Compute an upper bound for the compressed length */ | ||
1034 | ulg out_length = (ulg)s->last_lit*8L; | ||
1035 | ulg in_length = (ulg)((long)s->strstart - s->block_start); | ||
1036 | int dcode; | ||
1037 | for (dcode = 0; dcode < D_CODES; dcode++) { | ||
1038 | out_length += (ulg)s->dyn_dtree[dcode].Freq * | ||
1039 | (5L+extra_dbits[dcode]); | ||
1040 | } | ||
1041 | out_length >>= 3; | ||
1042 | Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ", | ||
1043 | s->last_lit, in_length, out_length, | ||
1044 | 100L - out_length*100L/in_length)); | ||
1045 | if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1; | ||
1046 | } | ||
1047 | #endif | ||
1048 | return (s->last_lit == s->lit_bufsize-1); | ||
1049 | /* We avoid equality with lit_bufsize because of wraparound at 64K | ||
1050 | * on 16 bit machines and because stored blocks are restricted to | ||
1051 | * 64K-1 bytes. | ||
1052 | */ | ||
1053 | } | ||
1054 | |||
1055 | /* =========================================================================== | ||
1056 | * Send the block data compressed using the given Huffman trees | ||
1057 | */ | ||
1058 | local void compress_block(s, ltree, dtree) | ||
1059 | deflate_state *s; | ||
1060 | ct_data *ltree; /* literal tree */ | ||
1061 | ct_data *dtree; /* distance tree */ | ||
1062 | { | ||
1063 | unsigned dist; /* distance of matched string */ | ||
1064 | int lc; /* match length or unmatched char (if dist == 0) */ | ||
1065 | unsigned lx = 0; /* running index in l_buf */ | ||
1066 | unsigned code; /* the code to send */ | ||
1067 | int extra; /* number of extra bits to send */ | ||
1068 | |||
1069 | if (s->last_lit != 0) do { | ||
1070 | dist = s->d_buf[lx]; | ||
1071 | lc = s->l_buf[lx++]; | ||
1072 | if (dist == 0) { | ||
1073 | send_code(s, lc, ltree); /* send a literal byte */ | ||
1074 | Tracecv(isgraph(lc), (stderr," '%c' ", lc)); | ||
1075 | } else { | ||
1076 | /* Here, lc is the match length - MIN_MATCH */ | ||
1077 | code = _length_code[lc]; | ||
1078 | send_code(s, code+LITERALS+1, ltree); /* send the length code */ | ||
1079 | extra = extra_lbits[code]; | ||
1080 | if (extra != 0) { | ||
1081 | lc -= base_length[code]; | ||
1082 | send_bits(s, lc, extra); /* send the extra length bits */ | ||
1083 | } | ||
1084 | dist--; /* dist is now the match distance - 1 */ | ||
1085 | code = d_code(dist); | ||
1086 | Assert (code < D_CODES, "bad d_code"); | ||
1087 | |||
1088 | send_code(s, code, dtree); /* send the distance code */ | ||
1089 | extra = extra_dbits[code]; | ||
1090 | if (extra != 0) { | ||
1091 | dist -= base_dist[code]; | ||
1092 | send_bits(s, dist, extra); /* send the extra distance bits */ | ||
1093 | } | ||
1094 | } /* literal or match pair ? */ | ||
1095 | |||
1096 | /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */ | ||
1097 | Assert((uInt)(s->pending) < s->lit_bufsize + 2*lx, | ||
1098 | "pendingBuf overflow"); | ||
1099 | |||
1100 | } while (lx < s->last_lit); | ||
1101 | |||
1102 | send_code(s, END_BLOCK, ltree); | ||
1103 | } | ||
1104 | |||
1105 | /* =========================================================================== | ||
1106 | * Check if the data type is TEXT or BINARY, using the following algorithm: | ||
1107 | * - TEXT if the two conditions below are satisfied: | ||
1108 | * a) There are no non-portable control characters belonging to the | ||
1109 | * "black list" (0..6, 14..25, 28..31). | ||
1110 | * b) There is at least one printable character belonging to the | ||
1111 | * "white list" (9 {TAB}, 10 {LF}, 13 {CR}, 32..255). | ||
1112 | * - BINARY otherwise. | ||
1113 | * - The following partially-portable control characters form a | ||
1114 | * "gray list" that is ignored in this detection algorithm: | ||
1115 | * (7 {BEL}, 8 {BS}, 11 {VT}, 12 {FF}, 26 {SUB}, 27 {ESC}). | ||
1116 | * IN assertion: the fields Freq of dyn_ltree are set. | ||
1117 | */ | ||
1118 | local int detect_data_type(s) | ||
1119 | deflate_state *s; | ||
1120 | { | ||
1121 | /* black_mask is the bit mask of black-listed bytes | ||
1122 | * set bits 0..6, 14..25, and 28..31 | ||
1123 | * 0xf3ffc07f = binary 11110011111111111100000001111111 | ||
1124 | */ | ||
1125 | unsigned long black_mask = 0xf3ffc07fUL; | ||
1126 | int n; | ||
1127 | |||
1128 | /* Check for non-textual ("black-listed") bytes. */ | ||
1129 | for (n = 0; n <= 31; n++, black_mask >>= 1) | ||
1130 | if ((black_mask & 1) && (s->dyn_ltree[n].Freq != 0)) | ||
1131 | return Z_BINARY; | ||
1132 | |||
1133 | /* Check for textual ("white-listed") bytes. */ | ||
1134 | if (s->dyn_ltree[9].Freq != 0 || s->dyn_ltree[10].Freq != 0 | ||
1135 | || s->dyn_ltree[13].Freq != 0) | ||
1136 | return Z_TEXT; | ||
1137 | for (n = 32; n < LITERALS; n++) | ||
1138 | if (s->dyn_ltree[n].Freq != 0) | ||
1139 | return Z_TEXT; | ||
1140 | |||
1141 | /* There are no "black-listed" or "white-listed" bytes: | ||
1142 | * this stream either is empty or has tolerated ("gray-listed") bytes only. | ||
1143 | */ | ||
1144 | return Z_BINARY; | ||
1145 | } | ||
1146 | |||
1147 | /* =========================================================================== | ||
1148 | * Reverse the first len bits of a code, using straightforward code (a faster | ||
1149 | * method would use a table) | ||
1150 | * IN assertion: 1 <= len <= 15 | ||
1151 | */ | ||
1152 | local unsigned bi_reverse(code, len) | ||
1153 | unsigned code; /* the value to invert */ | ||
1154 | int len; /* its bit length */ | ||
1155 | { | ||
1156 | register unsigned res = 0; | ||
1157 | do { | ||
1158 | res |= code & 1; | ||
1159 | code >>= 1, res <<= 1; | ||
1160 | } while (--len > 0); | ||
1161 | return res >> 1; | ||
1162 | } | ||
1163 | |||
1164 | /* =========================================================================== | ||
1165 | * Flush the bit buffer, keeping at most 7 bits in it. | ||
1166 | */ | ||
1167 | local void bi_flush(s) | ||
1168 | deflate_state *s; | ||
1169 | { | ||
1170 | if (s->bi_valid == 16) { | ||
1171 | put_short(s, s->bi_buf); | ||
1172 | s->bi_buf = 0; | ||
1173 | s->bi_valid = 0; | ||
1174 | } else if (s->bi_valid >= 8) { | ||
1175 | put_byte(s, (Byte)s->bi_buf); | ||
1176 | s->bi_buf >>= 8; | ||
1177 | s->bi_valid -= 8; | ||
1178 | } | ||
1179 | } | ||
1180 | |||
1181 | /* =========================================================================== | ||
1182 | * Flush the bit buffer and align the output on a byte boundary | ||
1183 | */ | ||
1184 | local void bi_windup(s) | ||
1185 | deflate_state *s; | ||
1186 | { | ||
1187 | if (s->bi_valid > 8) { | ||
1188 | put_short(s, s->bi_buf); | ||
1189 | } else if (s->bi_valid > 0) { | ||
1190 | put_byte(s, (Byte)s->bi_buf); | ||
1191 | } | ||
1192 | s->bi_buf = 0; | ||
1193 | s->bi_valid = 0; | ||
1194 | #ifdef DEBUG | ||
1195 | s->bits_sent = (s->bits_sent+7) & ~7; | ||
1196 | #endif | ||
1197 | } | ||
1198 | |||
1199 | /* =========================================================================== | ||
1200 | * Copy a stored block, storing first the length and its | ||
1201 | * one's complement if requested. | ||
1202 | */ | ||
1203 | local void copy_block(s, buf, len, header) | ||
1204 | deflate_state *s; | ||
1205 | charf *buf; /* the input data */ | ||
1206 | unsigned len; /* its length */ | ||
1207 | int header; /* true if block header must be written */ | ||
1208 | { | ||
1209 | bi_windup(s); /* align on byte boundary */ | ||
1210 | |||
1211 | if (header) { | ||
1212 | put_short(s, (ush)len); | ||
1213 | put_short(s, (ush)~len); | ||
1214 | #ifdef DEBUG | ||
1215 | s->bits_sent += 2*16; | ||
1216 | #endif | ||
1217 | } | ||
1218 | #ifdef DEBUG | ||
1219 | s->bits_sent += (ulg)len<<3; | ||
1220 | #endif | ||
1221 | while (len--) { | ||
1222 | put_byte(s, *buf++); | ||
1223 | } | ||
1224 | } | ||