1 | /* deflate.c -- compress data using the deflation algorithm |
2 | * Copyright (C) 1995-2016 Jean-loup Gailly and Mark Adler |
3 | * For conditions of distribution and use, see copyright notice in zlib.h |
4 | */ |
5 | |
6 | /* |
7 | * ALGORITHM |
8 | * |
9 | * The "deflation" process depends on being able to identify portions |
10 | * of the input text which are identical to earlier input (within a |
11 | * sliding window trailing behind the input currently being processed). |
12 | * |
13 | * The most straightforward technique turns out to be the fastest for |
14 | * most input files: try all possible matches and select the longest. |
15 | * The key feature of this algorithm is that insertions into the string |
16 | * dictionary are very simple and thus fast, and deletions are avoided |
17 | * completely. Insertions are performed at each input character, whereas |
18 | * string matches are performed only when the previous match ends. So it |
19 | * is preferable to spend more time in matches to allow very fast string |
20 | * insertions and avoid deletions. The matching algorithm for small |
21 | * strings is inspired from that of Rabin & Karp. A brute force approach |
22 | * is used to find longer strings when a small match has been found. |
23 | * A similar algorithm is used in comic (by Jan-Mark Wams) and freeze |
24 | * (by Leonid Broukhis). |
25 | * A previous version of this file used a more sophisticated algorithm |
26 | * (by Fiala and Greene) which is guaranteed to run in linear amortized |
27 | * time, but has a larger average cost, uses more memory and is patented. |
28 | * However the F&G algorithm may be faster for some highly redundant |
29 | * files if the parameter max_chain_length (described below) is too large. |
30 | * |
31 | * ACKNOWLEDGEMENTS |
32 | * |
33 | * The idea of lazy evaluation of matches is due to Jan-Mark Wams, and |
34 | * I found it in 'freeze' written by Leonid Broukhis. |
35 | * Thanks to many people for bug reports and testing. |
36 | * |
37 | * REFERENCES |
38 | * |
39 | * Deutsch, L.P.,"DEFLATE Compressed Data Format Specification". |
40 | * Available in https://tools.ietf.org/html/rfc1951 |
41 | * |
42 | * A description of the Rabin and Karp algorithm is given in the book |
43 | * "Algorithms" by R. Sedgewick, Addison-Wesley, p252. |
44 | * |
45 | * Fiala,E.R., and Greene,D.H. |
46 | * Data Compression with Finite Windows, Comm.ACM, 32,4 (1989) 490-595 |
47 | * |
48 | */ |
49 | |
50 | #include "zbuild.h" |
51 | #include "deflate.h" |
52 | #include "deflate_p.h" |
53 | #include "functable.h" |
54 | |
55 | const char PREFIX(deflate_copyright)[] = " deflate 1.2.11.f Copyright 1995-2016 Jean-loup Gailly and Mark Adler " ; |
56 | /* |
57 | If you use the zlib library in a product, an acknowledgment is welcome |
58 | in the documentation of your product. If for some reason you cannot |
59 | include such an acknowledgment, I would appreciate that you keep this |
60 | copyright string in the executable of your product. |
61 | */ |
62 | |
63 | /* =========================================================================== |
64 | * Architecture-specific hooks. |
65 | */ |
66 | #ifdef S390_DFLTCC_DEFLATE |
67 | # include "arch/s390/dfltcc_deflate.h" |
68 | #else |
69 | /* Memory management for the deflate state. Useful for allocating arch-specific extension blocks. */ |
70 | # define ZALLOC_STATE(strm, items, size) ZALLOC(strm, items, size) |
71 | # define ZFREE_STATE(strm, addr) ZFREE(strm, addr) |
72 | # define ZCOPY_STATE(dst, src, size) memcpy(dst, src, size) |
73 | /* Memory management for the window. Useful for allocation the aligned window. */ |
74 | # define ZALLOC_WINDOW(strm, items, size) ZALLOC(strm, items, size) |
75 | # define TRY_FREE_WINDOW(strm, addr) TRY_FREE(strm, addr) |
76 | /* Invoked at the beginning of deflateSetDictionary(). Useful for checking arch-specific window data. */ |
77 | # define DEFLATE_SET_DICTIONARY_HOOK(strm, dict, dict_len) do {} while (0) |
78 | /* Invoked at the beginning of deflateGetDictionary(). Useful for adjusting arch-specific window data. */ |
79 | # define DEFLATE_GET_DICTIONARY_HOOK(strm, dict, dict_len) do {} while (0) |
80 | /* Invoked at the end of deflateResetKeep(). Useful for initializing arch-specific extension blocks. */ |
81 | # define DEFLATE_RESET_KEEP_HOOK(strm) do {} while (0) |
82 | /* Invoked at the beginning of deflateParams(). Useful for updating arch-specific compression parameters. */ |
83 | # define DEFLATE_PARAMS_HOOK(strm, level, strategy, hook_flush) do {} while (0) |
84 | /* Returns whether the last deflate(flush) operation did everything it's supposed to do. */ |
85 | # define DEFLATE_DONE(strm, flush) 1 |
86 | /* Adjusts the upper bound on compressed data length based on compression parameters and uncompressed data length. |
87 | * Useful when arch-specific deflation code behaves differently than regular zlib-ng algorithms. */ |
88 | # define DEFLATE_BOUND_ADJUST_COMPLEN(strm, complen, sourceLen) do {} while (0) |
89 | /* Returns whether an optimistic upper bound on compressed data length should *not* be used. |
90 | * Useful when arch-specific deflation code behaves differently than regular zlib-ng algorithms. */ |
91 | # define DEFLATE_NEED_CONSERVATIVE_BOUND(strm) 0 |
92 | /* Invoked for each deflate() call. Useful for plugging arch-specific deflation code. */ |
93 | # define DEFLATE_HOOK(strm, flush, bstate) 0 |
94 | /* Returns whether zlib-ng should compute a checksum. Set to 0 if arch-specific deflation code already does that. */ |
95 | # define DEFLATE_NEED_CHECKSUM(strm) 1 |
96 | /* Returns whether reproducibility parameter can be set to a given value. */ |
97 | # define DEFLATE_CAN_SET_REPRODUCIBLE(strm, reproducible) 1 |
98 | #endif |
99 | |
100 | /* =========================================================================== |
101 | * Function prototypes. |
102 | */ |
103 | typedef block_state (*compress_func) (deflate_state *s, int flush); |
104 | /* Compression function. Returns the block state after the call. */ |
105 | |
106 | static int deflateStateCheck (PREFIX3(stream) *strm); |
107 | static block_state deflate_stored (deflate_state *s, int flush); |
108 | Z_INTERNAL block_state deflate_fast (deflate_state *s, int flush); |
109 | Z_INTERNAL block_state deflate_quick (deflate_state *s, int flush); |
110 | #ifndef NO_MEDIUM_STRATEGY |
111 | Z_INTERNAL block_state deflate_medium (deflate_state *s, int flush); |
112 | #endif |
113 | Z_INTERNAL block_state deflate_slow (deflate_state *s, int flush); |
114 | static block_state deflate_rle (deflate_state *s, int flush); |
115 | static block_state deflate_huff (deflate_state *s, int flush); |
116 | static void lm_init (deflate_state *s); |
117 | Z_INTERNAL unsigned read_buf (PREFIX3(stream) *strm, unsigned char *buf, unsigned size); |
118 | |
119 | extern void crc_reset(deflate_state *const s); |
120 | #ifdef X86_PCLMULQDQ_CRC |
121 | extern void crc_finalize(deflate_state *const s); |
122 | #endif |
123 | extern void copy_with_crc(PREFIX3(stream) *strm, unsigned char *dst, unsigned long size); |
124 | |
125 | /* =========================================================================== |
126 | * Local data |
127 | */ |
128 | |
129 | /* Values for max_lazy_match, good_match and max_chain_length, depending on |
130 | * the desired pack level (0..9). The values given below have been tuned to |
131 | * exclude worst case performance for pathological files. Better values may be |
132 | * found for specific files. |
133 | */ |
134 | typedef struct config_s { |
135 | uint16_t good_length; /* reduce lazy search above this match length */ |
136 | uint16_t max_lazy; /* do not perform lazy search above this match length */ |
137 | uint16_t nice_length; /* quit search above this match length */ |
138 | uint16_t max_chain; |
139 | compress_func func; |
140 | } config; |
141 | |
142 | static const config configuration_table[10] = { |
143 | /* good lazy nice chain */ |
144 | /* 0 */ {0, 0, 0, 0, deflate_stored}, /* store only */ |
145 | |
146 | #ifndef NO_QUICK_STRATEGY |
147 | /* 1 */ {.good_length: 4, .max_lazy: 4, .nice_length: 8, .max_chain: 4, .func: deflate_quick}, |
148 | /* 2 */ {.good_length: 4, .max_lazy: 4, .nice_length: 8, .max_chain: 4, .func: deflate_fast}, /* max speed, no lazy matches */ |
149 | #else |
150 | /* 1 */ {4, 4, 8, 4, deflate_fast}, /* max speed, no lazy matches */ |
151 | /* 2 */ {4, 5, 16, 8, deflate_fast}, |
152 | #endif |
153 | |
154 | /* 3 */ {.good_length: 4, .max_lazy: 6, .nice_length: 32, .max_chain: 32, .func: deflate_fast}, |
155 | |
156 | #ifdef NO_MEDIUM_STRATEGY |
157 | /* 4 */ {4, 4, 16, 16, deflate_slow}, /* lazy matches */ |
158 | /* 5 */ {8, 16, 32, 32, deflate_slow}, |
159 | /* 6 */ {8, 16, 128, 128, deflate_slow}, |
160 | #else |
161 | /* 4 */ {.good_length: 4, .max_lazy: 4, .nice_length: 16, .max_chain: 16, .func: deflate_medium}, /* lazy matches */ |
162 | /* 5 */ {.good_length: 8, .max_lazy: 16, .nice_length: 32, .max_chain: 32, .func: deflate_medium}, |
163 | /* 6 */ {.good_length: 8, .max_lazy: 16, .nice_length: 128, .max_chain: 128, .func: deflate_medium}, |
164 | #endif |
165 | |
166 | /* 7 */ {.good_length: 8, .max_lazy: 32, .nice_length: 128, .max_chain: 256, .func: deflate_slow}, |
167 | /* 8 */ {.good_length: 32, .max_lazy: 128, .nice_length: 258, .max_chain: 1024, .func: deflate_slow}, |
168 | /* 9 */ {.good_length: 32, .max_lazy: 258, .nice_length: 258, .max_chain: 4096, .func: deflate_slow}}; /* max compression */ |
169 | |
170 | /* Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4 |
171 | * For deflate_fast() (levels <= 3) good is ignored and lazy has a different |
172 | * meaning. |
173 | */ |
174 | |
175 | /* rank Z_BLOCK between Z_NO_FLUSH and Z_PARTIAL_FLUSH */ |
176 | #define RANK(f) (((f) * 2) - ((f) > 4 ? 9 : 0)) |
177 | |
178 | |
179 | /* =========================================================================== |
180 | * Initialize the hash table. prev[] will be initialized on the fly. |
181 | */ |
182 | #define CLEAR_HASH(s) do { \ |
183 | memset((unsigned char *)s->head, 0, HASH_SIZE * sizeof(*s->head)); \ |
184 | } while (0) |
185 | |
186 | /* =========================================================================== |
187 | * Slide the hash table when sliding the window down (could be avoided with 32 |
188 | * bit values at the expense of memory usage). We slide even when level == 0 to |
189 | * keep the hash table consistent if we switch back to level > 0 later. |
190 | */ |
191 | Z_INTERNAL void slide_hash_c(deflate_state *s) { |
192 | Pos *p; |
193 | unsigned n; |
194 | unsigned int wsize = s->w_size; |
195 | |
196 | n = HASH_SIZE; |
197 | p = &s->head[n]; |
198 | #ifdef NOT_TWEAK_COMPILER |
199 | do { |
200 | unsigned m; |
201 | m = *--p; |
202 | *p = (Pos)(m >= wsize ? m-wsize : 0); |
203 | } while (--n); |
204 | #else |
205 | /* As of I make this change, gcc (4.8.*) isn't able to vectorize |
206 | * this hot loop using saturated-subtraction on x86-64 architecture. |
207 | * To avoid this defect, we can change the loop such that |
208 | * o. the pointer advance forward, and |
209 | * o. demote the variable 'm' to be local to the loop, and |
210 | * choose type "Pos" (instead of 'unsigned int') for the |
211 | * variable to avoid unnecessary zero-extension. |
212 | */ |
213 | { |
214 | unsigned int i; |
215 | Pos *q = p - n; |
216 | for (i = 0; i < n; i++) { |
217 | Pos m = *q; |
218 | Pos t = (Pos)wsize; |
219 | *q++ = (Pos)(m >= t ? m-t: 0); |
220 | } |
221 | } |
222 | #endif /* NOT_TWEAK_COMPILER */ |
223 | |
224 | n = wsize; |
225 | p = &s->prev[n]; |
226 | #ifdef NOT_TWEAK_COMPILER |
227 | do { |
228 | unsigned m; |
229 | m = *--p; |
230 | *p = (Pos)(m >= wsize ? m-wsize : 0); |
231 | /* If n is not on any hash chain, prev[n] is garbage but |
232 | * its value will never be used. |
233 | */ |
234 | } while (--n); |
235 | #else |
236 | { |
237 | unsigned int i; |
238 | Pos *q = p - n; |
239 | for (i = 0; i < n; i++) { |
240 | Pos m = *q; |
241 | Pos t = (Pos)wsize; |
242 | *q++ = (Pos)(m >= t ? m-t: 0); |
243 | } |
244 | } |
245 | #endif /* NOT_TWEAK_COMPILER */ |
246 | } |
247 | |
248 | /* ========================================================================= */ |
249 | int32_t Z_EXPORT PREFIX(deflateInit_)(PREFIX3(stream) *strm, int32_t level, const char *version, int32_t stream_size) { |
250 | return PREFIX(deflateInit2_)(strm, level, Z_DEFLATED, MAX_WBITS, DEF_MEM_LEVEL, Z_DEFAULT_STRATEGY, version, stream_size); |
251 | /* Todo: ignore strm->next_in if we use it as window */ |
252 | } |
253 | |
254 | /* ========================================================================= */ |
255 | int32_t Z_EXPORT PREFIX(deflateInit2_)(PREFIX3(stream) *strm, int32_t level, int32_t method, int32_t windowBits, |
256 | int32_t memLevel, int32_t strategy, const char *version, int32_t stream_size) { |
257 | uint32_t window_padding = 0; |
258 | deflate_state *s; |
259 | int wrap = 1; |
260 | static const char my_version[] = PREFIX2(VERSION); |
261 | |
262 | #if defined(X86_FEATURES) |
263 | x86_check_features(); |
264 | #elif defined(ARM_FEATURES) |
265 | arm_check_features(); |
266 | #endif |
267 | |
268 | if (version == NULL || version[0] != my_version[0] || stream_size != sizeof(PREFIX3(stream))) { |
269 | return Z_VERSION_ERROR; |
270 | } |
271 | if (strm == NULL) |
272 | return Z_STREAM_ERROR; |
273 | |
274 | strm->msg = NULL; |
275 | if (strm->zalloc == NULL) { |
276 | strm->zalloc = zng_calloc; |
277 | strm->opaque = NULL; |
278 | } |
279 | if (strm->zfree == NULL) |
280 | strm->zfree = zng_cfree; |
281 | |
282 | if (level == Z_DEFAULT_COMPRESSION) |
283 | level = 6; |
284 | |
285 | if (windowBits < 0) { /* suppress zlib wrapper */ |
286 | wrap = 0; |
287 | windowBits = -windowBits; |
288 | #ifdef GZIP |
289 | } else if (windowBits > 15) { |
290 | wrap = 2; /* write gzip wrapper instead */ |
291 | windowBits -= 16; |
292 | #endif |
293 | } |
294 | if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != Z_DEFLATED || windowBits < 8 || |
295 | windowBits > 15 || level < 0 || level > 9 || strategy < 0 || strategy > Z_FIXED || |
296 | (windowBits == 8 && wrap != 1)) { |
297 | return Z_STREAM_ERROR; |
298 | } |
299 | if (windowBits == 8) |
300 | windowBits = 9; /* until 256-byte window bug fixed */ |
301 | |
302 | #if !defined(NO_QUICK_STRATEGY) && !defined(S390_DFLTCC_DEFLATE) |
303 | if (level == 1) |
304 | windowBits = 13; |
305 | #endif |
306 | |
307 | s = (deflate_state *) ZALLOC_STATE(strm, 1, sizeof(deflate_state)); |
308 | if (s == NULL) |
309 | return Z_MEM_ERROR; |
310 | strm->state = (struct internal_state *)s; |
311 | s->strm = strm; |
312 | s->status = INIT_STATE; /* to pass state test in deflateReset() */ |
313 | |
314 | s->wrap = wrap; |
315 | s->gzhead = NULL; |
316 | s->w_bits = (unsigned int)windowBits; |
317 | s->w_size = 1 << s->w_bits; |
318 | s->w_mask = s->w_size - 1; |
319 | |
320 | #ifdef X86_PCLMULQDQ_CRC |
321 | window_padding = 8; |
322 | #endif |
323 | |
324 | s->window = (unsigned char *) ZALLOC_WINDOW(strm, s->w_size + window_padding, 2*sizeof(unsigned char)); |
325 | s->prev = (Pos *) ZALLOC(strm, s->w_size, sizeof(Pos)); |
326 | memset(s: s->prev, c: 0, n: s->w_size * sizeof(Pos)); |
327 | s->head = (Pos *) ZALLOC(strm, HASH_SIZE, sizeof(Pos)); |
328 | |
329 | s->high_water = 0; /* nothing written to s->window yet */ |
330 | |
331 | s->lit_bufsize = 1 << (memLevel + 6); /* 16K elements by default */ |
332 | |
333 | /* We overlay pending_buf and sym_buf. This works since the average size |
334 | * for length/distance pairs over any compressed block is assured to be 31 |
335 | * bits or less. |
336 | * |
337 | * Analysis: The longest fixed codes are a length code of 8 bits plus 5 |
338 | * extra bits, for lengths 131 to 257. The longest fixed distance codes are |
339 | * 5 bits plus 13 extra bits, for distances 16385 to 32768. The longest |
340 | * possible fixed-codes length/distance pair is then 31 bits total. |
341 | * |
342 | * sym_buf starts one-fourth of the way into pending_buf. So there are |
343 | * three bytes in sym_buf for every four bytes in pending_buf. Each symbol |
344 | * in sym_buf is three bytes -- two for the distance and one for the |
345 | * literal/length. As each symbol is consumed, the pointer to the next |
346 | * sym_buf value to read moves forward three bytes. From that symbol, up to |
347 | * 31 bits are written to pending_buf. The closest the written pending_buf |
348 | * bits gets to the next sym_buf symbol to read is just before the last |
349 | * code is written. At that time, 31*(n-2) bits have been written, just |
350 | * after 24*(n-2) bits have been consumed from sym_buf. sym_buf starts at |
351 | * 8*n bits into pending_buf. (Note that the symbol buffer fills when n-1 |
352 | * symbols are written.) The closest the writing gets to what is unread is |
353 | * then n+14 bits. Here n is lit_bufsize, which is 16384 by default, and |
354 | * can range from 128 to 32768. |
355 | * |
356 | * Therefore, at a minimum, there are 142 bits of space between what is |
357 | * written and what is read in the overlain buffers, so the symbols cannot |
358 | * be overwritten by the compressed data. That space is actually 139 bits, |
359 | * due to the three-bit fixed-code block header. |
360 | * |
361 | * That covers the case where either Z_FIXED is specified, forcing fixed |
362 | * codes, or when the use of fixed codes is chosen, because that choice |
363 | * results in a smaller compressed block than dynamic codes. That latter |
364 | * condition then assures that the above analysis also covers all dynamic |
365 | * blocks. A dynamic-code block will only be chosen to be emitted if it has |
366 | * fewer bits than a fixed-code block would for the same set of symbols. |
367 | * Therefore its average symbol length is assured to be less than 31. So |
368 | * the compressed data for a dynamic block also cannot overwrite the |
369 | * symbols from which it is being constructed. |
370 | */ |
371 | |
372 | s->pending_buf = (unsigned char *) ZALLOC(strm, s->lit_bufsize, 4); |
373 | s->pending_buf_size = s->lit_bufsize * 4; |
374 | |
375 | if (s->window == NULL || s->prev == NULL || s->head == NULL || s->pending_buf == NULL) { |
376 | s->status = FINISH_STATE; |
377 | strm->msg = ERR_MSG(Z_MEM_ERROR); |
378 | PREFIX(deflateEnd)(strm); |
379 | return Z_MEM_ERROR; |
380 | } |
381 | s->sym_buf = s->pending_buf + s->lit_bufsize; |
382 | s->sym_end = (s->lit_bufsize - 1) * 3; |
383 | /* We avoid equality with lit_bufsize*3 because of wraparound at 64K |
384 | * on 16 bit machines and because stored blocks are restricted to |
385 | * 64K-1 bytes. |
386 | */ |
387 | |
388 | s->level = level; |
389 | s->strategy = strategy; |
390 | s->block_open = 0; |
391 | s->reproducible = 0; |
392 | |
393 | return PREFIX(deflateReset)(strm); |
394 | } |
395 | |
396 | /* ========================================================================= |
397 | * Check for a valid deflate stream state. Return 0 if ok, 1 if not. |
398 | */ |
399 | static int deflateStateCheck (PREFIX3(stream) *strm) { |
400 | deflate_state *s; |
401 | if (strm == NULL || strm->zalloc == (alloc_func)0 || strm->zfree == (free_func)0) |
402 | return 1; |
403 | s = strm->state; |
404 | if (s == NULL || s->strm != strm || (s->status != INIT_STATE && |
405 | #ifdef GZIP |
406 | s->status != GZIP_STATE && |
407 | #endif |
408 | s->status != EXTRA_STATE && |
409 | s->status != NAME_STATE && |
410 | s->status != COMMENT_STATE && |
411 | s->status != HCRC_STATE && |
412 | s->status != BUSY_STATE && |
413 | s->status != FINISH_STATE)) |
414 | return 1; |
415 | return 0; |
416 | } |
417 | |
418 | /* ========================================================================= */ |
419 | int32_t Z_EXPORT PREFIX(deflateSetDictionary)(PREFIX3(stream) *strm, const uint8_t *dictionary, uint32_t dictLength) { |
420 | deflate_state *s; |
421 | unsigned int str, n; |
422 | int wrap; |
423 | uint32_t avail; |
424 | const unsigned char *next; |
425 | |
426 | if (deflateStateCheck(strm) || dictionary == NULL) |
427 | return Z_STREAM_ERROR; |
428 | s = strm->state; |
429 | wrap = s->wrap; |
430 | if (wrap == 2 || (wrap == 1 && s->status != INIT_STATE) || s->lookahead) |
431 | return Z_STREAM_ERROR; |
432 | |
433 | /* when using zlib wrappers, compute Adler-32 for provided dictionary */ |
434 | if (wrap == 1) |
435 | strm->adler = functable.adler32(strm->adler, dictionary, dictLength); |
436 | DEFLATE_SET_DICTIONARY_HOOK(strm, dictionary, dictLength); /* hook for IBM Z DFLTCC */ |
437 | s->wrap = 0; /* avoid computing Adler-32 in read_buf */ |
438 | |
439 | /* if dictionary would fill window, just replace the history */ |
440 | if (dictLength >= s->w_size) { |
441 | if (wrap == 0) { /* already empty otherwise */ |
442 | CLEAR_HASH(s); |
443 | s->strstart = 0; |
444 | s->block_start = 0; |
445 | s->insert = 0; |
446 | } |
447 | dictionary += dictLength - s->w_size; /* use the tail */ |
448 | dictLength = s->w_size; |
449 | } |
450 | |
451 | /* insert dictionary into window and hash */ |
452 | avail = strm->avail_in; |
453 | next = strm->next_in; |
454 | strm->avail_in = dictLength; |
455 | strm->next_in = (z_const unsigned char *)dictionary; |
456 | fill_window(s); |
457 | while (s->lookahead >= MIN_MATCH) { |
458 | str = s->strstart; |
459 | n = s->lookahead - (MIN_MATCH-1); |
460 | functable.insert_string(s, str, n); |
461 | s->strstart = str + n; |
462 | s->lookahead = MIN_MATCH-1; |
463 | fill_window(s); |
464 | } |
465 | s->strstart += s->lookahead; |
466 | s->block_start = (int)s->strstart; |
467 | s->insert = s->lookahead; |
468 | s->lookahead = 0; |
469 | s->prev_length = MIN_MATCH-1; |
470 | s->match_available = 0; |
471 | strm->next_in = (z_const unsigned char *)next; |
472 | strm->avail_in = avail; |
473 | s->wrap = wrap; |
474 | return Z_OK; |
475 | } |
476 | |
477 | /* ========================================================================= */ |
478 | int32_t Z_EXPORT PREFIX(deflateGetDictionary)(PREFIX3(stream) *strm, uint8_t *dictionary, uint32_t *dictLength) { |
479 | deflate_state *s; |
480 | unsigned int len; |
481 | |
482 | if (deflateStateCheck(strm)) |
483 | return Z_STREAM_ERROR; |
484 | DEFLATE_GET_DICTIONARY_HOOK(strm, dictionary, dictLength); /* hook for IBM Z DFLTCC */ |
485 | s = strm->state; |
486 | len = s->strstart + s->lookahead; |
487 | if (len > s->w_size) |
488 | len = s->w_size; |
489 | if (dictionary != NULL && len) |
490 | memcpy(dest: dictionary, src: s->window + s->strstart + s->lookahead - len, n: len); |
491 | if (dictLength != NULL) |
492 | *dictLength = len; |
493 | return Z_OK; |
494 | } |
495 | |
496 | /* ========================================================================= */ |
497 | int32_t Z_EXPORT PREFIX(deflateResetKeep)(PREFIX3(stream) *strm) { |
498 | deflate_state *s; |
499 | |
500 | if (deflateStateCheck(strm)) |
501 | return Z_STREAM_ERROR; |
502 | |
503 | strm->total_in = strm->total_out = 0; |
504 | strm->msg = NULL; /* use zfree if we ever allocate msg dynamically */ |
505 | strm->data_type = Z_UNKNOWN; |
506 | |
507 | s = (deflate_state *)strm->state; |
508 | s->pending = 0; |
509 | s->pending_out = s->pending_buf; |
510 | |
511 | if (s->wrap < 0) |
512 | s->wrap = -s->wrap; /* was made negative by deflate(..., Z_FINISH); */ |
513 | |
514 | s->status = |
515 | #ifdef GZIP |
516 | s->wrap == 2 ? GZIP_STATE : |
517 | #endif |
518 | INIT_STATE; |
519 | |
520 | #ifdef GZIP |
521 | if (s->wrap == 2) |
522 | crc_reset(s); |
523 | else |
524 | #endif |
525 | strm->adler = ADLER32_INITIAL_VALUE; |
526 | s->last_flush = -2; |
527 | |
528 | zng_tr_init(s); |
529 | |
530 | DEFLATE_RESET_KEEP_HOOK(strm); /* hook for IBM Z DFLTCC */ |
531 | |
532 | return Z_OK; |
533 | } |
534 | |
535 | /* ========================================================================= */ |
536 | int32_t Z_EXPORT PREFIX(deflateReset)(PREFIX3(stream) *strm) { |
537 | int ret; |
538 | |
539 | ret = PREFIX(deflateResetKeep)(strm); |
540 | if (ret == Z_OK) |
541 | lm_init(s: strm->state); |
542 | return ret; |
543 | } |
544 | |
545 | /* ========================================================================= */ |
546 | int32_t Z_EXPORT PREFIX()(PREFIX3(stream) *strm, PREFIX(gz_headerp) head) { |
547 | if (deflateStateCheck(strm) || strm->state->wrap != 2) |
548 | return Z_STREAM_ERROR; |
549 | strm->state->gzhead = head; |
550 | return Z_OK; |
551 | } |
552 | |
553 | /* ========================================================================= */ |
554 | int32_t Z_EXPORT PREFIX(deflatePending)(PREFIX3(stream) *strm, uint32_t *pending, int32_t *bits) { |
555 | if (deflateStateCheck(strm)) |
556 | return Z_STREAM_ERROR; |
557 | if (pending != NULL) |
558 | *pending = strm->state->pending; |
559 | if (bits != NULL) |
560 | *bits = strm->state->bi_valid; |
561 | return Z_OK; |
562 | } |
563 | |
564 | /* ========================================================================= */ |
565 | int32_t Z_EXPORT PREFIX(deflatePrime)(PREFIX3(stream) *strm, int32_t bits, int32_t value) { |
566 | deflate_state *s; |
567 | uint64_t value64 = (uint64_t)value; |
568 | int32_t put; |
569 | |
570 | if (deflateStateCheck(strm)) |
571 | return Z_STREAM_ERROR; |
572 | s = strm->state; |
573 | if (bits < 0 || bits > BIT_BUF_SIZE || bits > (int32_t)(sizeof(value) << 3) || |
574 | s->sym_buf < s->pending_out + ((BIT_BUF_SIZE + 7) >> 3)) |
575 | return Z_BUF_ERROR; |
576 | do { |
577 | put = BIT_BUF_SIZE - s->bi_valid; |
578 | if (put > bits) |
579 | put = bits; |
580 | if (s->bi_valid == 0) |
581 | s->bi_buf = value64; |
582 | else |
583 | s->bi_buf |= (value64 & ((UINT64_C(1) << put) - 1)) << s->bi_valid; |
584 | s->bi_valid += put; |
585 | zng_tr_flush_bits(s); |
586 | value64 >>= put; |
587 | bits -= put; |
588 | } while (bits); |
589 | return Z_OK; |
590 | } |
591 | |
592 | /* ========================================================================= */ |
593 | int32_t Z_EXPORT PREFIX(deflateParams)(PREFIX3(stream) *strm, int32_t level, int32_t strategy) { |
594 | deflate_state *s; |
595 | compress_func func; |
596 | int hook_flush = Z_NO_FLUSH; |
597 | |
598 | if (deflateStateCheck(strm)) |
599 | return Z_STREAM_ERROR; |
600 | s = strm->state; |
601 | |
602 | if (level == Z_DEFAULT_COMPRESSION) |
603 | level = 6; |
604 | if (level < 0 || level > 9 || strategy < 0 || strategy > Z_FIXED) |
605 | return Z_STREAM_ERROR; |
606 | DEFLATE_PARAMS_HOOK(strm, level, strategy, &hook_flush); /* hook for IBM Z DFLTCC */ |
607 | func = configuration_table[s->level].func; |
608 | |
609 | if (((strategy != s->strategy || func != configuration_table[level].func) && s->last_flush != -2) |
610 | || hook_flush != Z_NO_FLUSH) { |
611 | /* Flush the last buffer. Use Z_BLOCK mode, unless the hook requests a "stronger" one. */ |
612 | int flush = RANK(hook_flush) > RANK(Z_BLOCK) ? hook_flush : Z_BLOCK; |
613 | int err = PREFIX(deflate)(strm, flush); |
614 | if (err == Z_STREAM_ERROR) |
615 | return err; |
616 | if (strm->avail_in || ((int)s->strstart - s->block_start) + s->lookahead || !DEFLATE_DONE(strm, flush)) |
617 | return Z_BUF_ERROR; |
618 | } |
619 | if (s->level != level) { |
620 | if (s->level == 0 && s->matches != 0) { |
621 | if (s->matches == 1) { |
622 | functable.slide_hash(s); |
623 | } else { |
624 | CLEAR_HASH(s); |
625 | } |
626 | s->matches = 0; |
627 | } |
628 | s->level = level; |
629 | s->max_lazy_match = configuration_table[level].max_lazy; |
630 | s->good_match = configuration_table[level].good_length; |
631 | s->nice_match = configuration_table[level].nice_length; |
632 | s->max_chain_length = configuration_table[level].max_chain; |
633 | } |
634 | s->strategy = strategy; |
635 | return Z_OK; |
636 | } |
637 | |
638 | /* ========================================================================= */ |
639 | int32_t Z_EXPORT PREFIX(deflateTune)(PREFIX3(stream) *strm, int32_t good_length, int32_t max_lazy, int32_t nice_length, int32_t max_chain) { |
640 | deflate_state *s; |
641 | |
642 | if (deflateStateCheck(strm)) |
643 | return Z_STREAM_ERROR; |
644 | s = strm->state; |
645 | s->good_match = (unsigned int)good_length; |
646 | s->max_lazy_match = (unsigned int)max_lazy; |
647 | s->nice_match = nice_length; |
648 | s->max_chain_length = (unsigned int)max_chain; |
649 | return Z_OK; |
650 | } |
651 | |
652 | /* ========================================================================= |
653 | * For the default windowBits of 15 and memLevel of 8, this function returns |
654 | * a close to exact, as well as small, upper bound on the compressed size. |
655 | * They are coded as constants here for a reason--if the #define's are |
656 | * changed, then this function needs to be changed as well. The return |
657 | * value for 15 and 8 only works for those exact settings. |
658 | * |
659 | * For any setting other than those defaults for windowBits and memLevel, |
660 | * the value returned is a conservative worst case for the maximum expansion |
661 | * resulting from using fixed blocks instead of stored blocks, which deflate |
662 | * can emit on compressed data for some combinations of the parameters. |
663 | * |
664 | * This function could be more sophisticated to provide closer upper bounds for |
665 | * every combination of windowBits and memLevel. But even the conservative |
666 | * upper bound of about 14% expansion does not seem onerous for output buffer |
667 | * allocation. |
668 | */ |
669 | unsigned long Z_EXPORT PREFIX(deflateBound)(PREFIX3(stream) *strm, unsigned long sourceLen) { |
670 | deflate_state *s; |
671 | unsigned long complen, wraplen; |
672 | |
673 | /* conservative upper bound for compressed data */ |
674 | complen = sourceLen + ((sourceLen + 7) >> 3) + ((sourceLen + 63) >> 6) + 5; |
675 | DEFLATE_BOUND_ADJUST_COMPLEN(strm, complen, sourceLen); /* hook for IBM Z DFLTCC */ |
676 | |
677 | /* if can't get parameters, return conservative bound plus zlib wrapper */ |
678 | if (deflateStateCheck(strm)) |
679 | return complen + 6; |
680 | |
681 | /* compute wrapper length */ |
682 | s = strm->state; |
683 | switch (s->wrap) { |
684 | case 0: /* raw deflate */ |
685 | wraplen = 0; |
686 | break; |
687 | case 1: /* zlib wrapper */ |
688 | wraplen = ZLIB_WRAPLEN + (s->strstart ? 4 : 0); |
689 | break; |
690 | #ifdef GZIP |
691 | case 2: /* gzip wrapper */ |
692 | wraplen = GZIP_WRAPLEN; |
693 | if (s->gzhead != NULL) { /* user-supplied gzip header */ |
694 | unsigned char *str; |
695 | if (s->gzhead->extra != NULL) { |
696 | wraplen += 2 + s->gzhead->extra_len; |
697 | } |
698 | str = s->gzhead->name; |
699 | if (str != NULL) { |
700 | do { |
701 | wraplen++; |
702 | } while (*str++); |
703 | } |
704 | str = s->gzhead->comment; |
705 | if (str != NULL) { |
706 | do { |
707 | wraplen++; |
708 | } while (*str++); |
709 | } |
710 | if (s->gzhead->hcrc) |
711 | wraplen += 2; |
712 | } |
713 | break; |
714 | #endif |
715 | default: /* for compiler happiness */ |
716 | wraplen = ZLIB_WRAPLEN; |
717 | } |
718 | |
719 | /* if not default parameters, return conservative bound */ |
720 | if (DEFLATE_NEED_CONSERVATIVE_BOUND(strm) || /* hook for IBM Z DFLTCC */ |
721 | s->w_bits != 15 || HASH_BITS < 15) |
722 | return complen + wraplen; |
723 | |
724 | #ifndef NO_QUICK_STRATEGY |
725 | return sourceLen /* The source size itself */ |
726 | + DEFLATE_QUICK_OVERHEAD(sourceLen) /* Source encoding overhead, padded to next full byte */ |
727 | + DEFLATE_BLOCK_OVERHEAD /* Deflate block overhead bytes */ |
728 | + wraplen; /* none, zlib or gzip wrapper */ |
729 | #else |
730 | return sourceLen + (sourceLen >> 4) + 7 + wraplen; |
731 | #endif |
732 | } |
733 | |
734 | /* ========================================================================= |
735 | * Flush as much pending output as possible. All deflate() output, except for |
736 | * some deflate_stored() output, goes through this function so some |
737 | * applications may wish to modify it to avoid allocating a large |
738 | * strm->next_out buffer and copying into it. (See also read_buf()). |
739 | */ |
740 | Z_INTERNAL void flush_pending(PREFIX3(stream) *strm) { |
741 | uint32_t len; |
742 | deflate_state *s = strm->state; |
743 | |
744 | zng_tr_flush_bits(s); |
745 | len = s->pending; |
746 | if (len > strm->avail_out) |
747 | len = strm->avail_out; |
748 | if (len == 0) |
749 | return; |
750 | |
751 | Tracev((stderr, "[FLUSH]" )); |
752 | memcpy(dest: strm->next_out, src: s->pending_out, n: len); |
753 | strm->next_out += len; |
754 | s->pending_out += len; |
755 | strm->total_out += len; |
756 | strm->avail_out -= len; |
757 | s->pending -= len; |
758 | if (s->pending == 0) |
759 | s->pending_out = s->pending_buf; |
760 | } |
761 | |
762 | /* =========================================================================== |
763 | * Update the header CRC with the bytes s->pending_buf[beg..s->pending - 1]. |
764 | */ |
765 | #define HCRC_UPDATE(beg) \ |
766 | do { \ |
767 | if (s->gzhead->hcrc && s->pending > (beg)) \ |
768 | strm->adler = PREFIX(crc32)(strm->adler, s->pending_buf + (beg), s->pending - (beg)); \ |
769 | } while (0) |
770 | |
771 | /* ========================================================================= */ |
772 | int32_t Z_EXPORT PREFIX(deflate)(PREFIX3(stream) *strm, int32_t flush) { |
773 | int32_t old_flush; /* value of flush param for previous deflate call */ |
774 | deflate_state *s; |
775 | |
776 | if (deflateStateCheck(strm) || flush > Z_BLOCK || flush < 0) |
777 | return Z_STREAM_ERROR; |
778 | s = strm->state; |
779 | |
780 | if (strm->next_out == NULL || (strm->avail_in != 0 && strm->next_in == NULL) |
781 | || (s->status == FINISH_STATE && flush != Z_FINISH)) { |
782 | ERR_RETURN(strm, Z_STREAM_ERROR); |
783 | } |
784 | if (strm->avail_out == 0) { |
785 | ERR_RETURN(strm, Z_BUF_ERROR); |
786 | } |
787 | |
788 | old_flush = s->last_flush; |
789 | s->last_flush = flush; |
790 | |
791 | /* Flush as much pending output as possible */ |
792 | if (s->pending != 0) { |
793 | flush_pending(strm); |
794 | if (strm->avail_out == 0) { |
795 | /* Since avail_out is 0, deflate will be called again with |
796 | * more output space, but possibly with both pending and |
797 | * avail_in equal to zero. There won't be anything to do, |
798 | * but this is not an error situation so make sure we |
799 | * return OK instead of BUF_ERROR at next call of deflate: |
800 | */ |
801 | s->last_flush = -1; |
802 | return Z_OK; |
803 | } |
804 | |
805 | /* Make sure there is something to do and avoid duplicate consecutive |
806 | * flushes. For repeated and useless calls with Z_FINISH, we keep |
807 | * returning Z_STREAM_END instead of Z_BUF_ERROR. |
808 | */ |
809 | } else if (strm->avail_in == 0 && RANK(flush) <= RANK(old_flush) && flush != Z_FINISH) { |
810 | ERR_RETURN(strm, Z_BUF_ERROR); |
811 | } |
812 | |
813 | /* User must not provide more input after the first FINISH: */ |
814 | if (s->status == FINISH_STATE && strm->avail_in != 0) { |
815 | ERR_RETURN(strm, Z_BUF_ERROR); |
816 | } |
817 | |
818 | /* Write the header */ |
819 | if (s->status == INIT_STATE && s->wrap == 0) |
820 | s->status = BUSY_STATE; |
821 | if (s->status == INIT_STATE) { |
822 | /* zlib header */ |
823 | unsigned int = (Z_DEFLATED + ((s->w_bits-8)<<4)) << 8; |
824 | unsigned int level_flags; |
825 | |
826 | if (s->strategy >= Z_HUFFMAN_ONLY || s->level < 2) |
827 | level_flags = 0; |
828 | else if (s->level < 6) |
829 | level_flags = 1; |
830 | else if (s->level == 6) |
831 | level_flags = 2; |
832 | else |
833 | level_flags = 3; |
834 | header |= (level_flags << 6); |
835 | if (s->strstart != 0) |
836 | header |= PRESET_DICT; |
837 | header += 31 - (header % 31); |
838 | |
839 | put_short_msb(s, w: (uint16_t)header); |
840 | |
841 | /* Save the adler32 of the preset dictionary: */ |
842 | if (s->strstart != 0) |
843 | put_uint32_msb(s, dw: strm->adler); |
844 | strm->adler = ADLER32_INITIAL_VALUE; |
845 | s->status = BUSY_STATE; |
846 | |
847 | /* Compression must start with an empty pending buffer */ |
848 | flush_pending(strm); |
849 | if (s->pending != 0) { |
850 | s->last_flush = -1; |
851 | return Z_OK; |
852 | } |
853 | } |
854 | #ifdef GZIP |
855 | if (s->status == GZIP_STATE) { |
856 | /* gzip header */ |
857 | crc_reset(s); |
858 | put_byte(s, 31); |
859 | put_byte(s, 139); |
860 | put_byte(s, 8); |
861 | if (s->gzhead == NULL) { |
862 | put_uint32(s, dw: 0); |
863 | put_byte(s, 0); |
864 | put_byte(s, s->level == 9 ? 2 : |
865 | (s->strategy >= Z_HUFFMAN_ONLY || s->level < 2 ? 4 : 0)); |
866 | put_byte(s, OS_CODE); |
867 | s->status = BUSY_STATE; |
868 | |
869 | /* Compression must start with an empty pending buffer */ |
870 | flush_pending(strm); |
871 | if (s->pending != 0) { |
872 | s->last_flush = -1; |
873 | return Z_OK; |
874 | } |
875 | } else { |
876 | put_byte(s, (s->gzhead->text ? 1 : 0) + |
877 | (s->gzhead->hcrc ? 2 : 0) + |
878 | (s->gzhead->extra == NULL ? 0 : 4) + |
879 | (s->gzhead->name == NULL ? 0 : 8) + |
880 | (s->gzhead->comment == NULL ? 0 : 16) |
881 | ); |
882 | put_uint32(s, dw: s->gzhead->time); |
883 | put_byte(s, s->level == 9 ? 2 : (s->strategy >= Z_HUFFMAN_ONLY || s->level < 2 ? 4 : 0)); |
884 | put_byte(s, s->gzhead->os & 0xff); |
885 | if (s->gzhead->extra != NULL) |
886 | put_short(s, w: (uint16_t)s->gzhead->extra_len); |
887 | if (s->gzhead->hcrc) |
888 | strm->adler = PREFIX(crc32)(crc: strm->adler, buf: s->pending_buf, len: s->pending); |
889 | s->gzindex = 0; |
890 | s->status = EXTRA_STATE; |
891 | } |
892 | } |
893 | if (s->status == EXTRA_STATE) { |
894 | if (s->gzhead->extra != NULL) { |
895 | uint32_t beg = s->pending; /* start of bytes to update crc */ |
896 | uint32_t left = (s->gzhead->extra_len & 0xffff) - s->gzindex; |
897 | |
898 | while (s->pending + left > s->pending_buf_size) { |
899 | uint32_t copy = s->pending_buf_size - s->pending; |
900 | memcpy(dest: s->pending_buf + s->pending, src: s->gzhead->extra + s->gzindex, n: copy); |
901 | s->pending = s->pending_buf_size; |
902 | HCRC_UPDATE(beg); |
903 | s->gzindex += copy; |
904 | flush_pending(strm); |
905 | if (s->pending != 0) { |
906 | s->last_flush = -1; |
907 | return Z_OK; |
908 | } |
909 | beg = 0; |
910 | left -= copy; |
911 | } |
912 | memcpy(dest: s->pending_buf + s->pending, src: s->gzhead->extra + s->gzindex, n: left); |
913 | s->pending += left; |
914 | HCRC_UPDATE(beg); |
915 | s->gzindex = 0; |
916 | } |
917 | s->status = NAME_STATE; |
918 | } |
919 | if (s->status == NAME_STATE) { |
920 | if (s->gzhead->name != NULL) { |
921 | uint32_t beg = s->pending; /* start of bytes to update crc */ |
922 | unsigned char val; |
923 | |
924 | do { |
925 | if (s->pending == s->pending_buf_size) { |
926 | HCRC_UPDATE(beg); |
927 | flush_pending(strm); |
928 | if (s->pending != 0) { |
929 | s->last_flush = -1; |
930 | return Z_OK; |
931 | } |
932 | beg = 0; |
933 | } |
934 | val = s->gzhead->name[s->gzindex++]; |
935 | put_byte(s, val); |
936 | } while (val != 0); |
937 | HCRC_UPDATE(beg); |
938 | s->gzindex = 0; |
939 | } |
940 | s->status = COMMENT_STATE; |
941 | } |
942 | if (s->status == COMMENT_STATE) { |
943 | if (s->gzhead->comment != NULL) { |
944 | uint32_t beg = s->pending; /* start of bytes to update crc */ |
945 | unsigned char val; |
946 | |
947 | do { |
948 | if (s->pending == s->pending_buf_size) { |
949 | HCRC_UPDATE(beg); |
950 | flush_pending(strm); |
951 | if (s->pending != 0) { |
952 | s->last_flush = -1; |
953 | return Z_OK; |
954 | } |
955 | beg = 0; |
956 | } |
957 | val = s->gzhead->comment[s->gzindex++]; |
958 | put_byte(s, val); |
959 | } while (val != 0); |
960 | HCRC_UPDATE(beg); |
961 | } |
962 | s->status = HCRC_STATE; |
963 | } |
964 | if (s->status == HCRC_STATE) { |
965 | if (s->gzhead->hcrc) { |
966 | if (s->pending + 2 > s->pending_buf_size) { |
967 | flush_pending(strm); |
968 | if (s->pending != 0) { |
969 | s->last_flush = -1; |
970 | return Z_OK; |
971 | } |
972 | } |
973 | put_short(s, w: (uint16_t)strm->adler); |
974 | crc_reset(s); |
975 | } |
976 | s->status = BUSY_STATE; |
977 | |
978 | /* Compression must start with an empty pending buffer */ |
979 | flush_pending(strm); |
980 | if (s->pending != 0) { |
981 | s->last_flush = -1; |
982 | return Z_OK; |
983 | } |
984 | } |
985 | #endif |
986 | |
987 | /* Start a new block or continue the current one. |
988 | */ |
989 | if (strm->avail_in != 0 || s->lookahead != 0 || (flush != Z_NO_FLUSH && s->status != FINISH_STATE)) { |
990 | block_state bstate; |
991 | |
992 | bstate = DEFLATE_HOOK(strm, flush, &bstate) ? bstate : /* hook for IBM Z DFLTCC */ |
993 | s->level == 0 ? deflate_stored(s, flush) : |
994 | s->strategy == Z_HUFFMAN_ONLY ? deflate_huff(s, flush) : |
995 | s->strategy == Z_RLE ? deflate_rle(s, flush) : |
996 | (*(configuration_table[s->level].func))(s, flush); |
997 | |
998 | if (bstate == finish_started || bstate == finish_done) { |
999 | s->status = FINISH_STATE; |
1000 | } |
1001 | if (bstate == need_more || bstate == finish_started) { |
1002 | if (strm->avail_out == 0) { |
1003 | s->last_flush = -1; /* avoid BUF_ERROR next call, see above */ |
1004 | } |
1005 | return Z_OK; |
1006 | /* If flush != Z_NO_FLUSH && avail_out == 0, the next call |
1007 | * of deflate should use the same flush parameter to make sure |
1008 | * that the flush is complete. So we don't have to output an |
1009 | * empty block here, this will be done at next call. This also |
1010 | * ensures that for a very small output buffer, we emit at most |
1011 | * one empty block. |
1012 | */ |
1013 | } |
1014 | if (bstate == block_done) { |
1015 | if (flush == Z_PARTIAL_FLUSH) { |
1016 | zng_tr_align(s); |
1017 | } else if (flush != Z_BLOCK) { /* FULL_FLUSH or SYNC_FLUSH */ |
1018 | zng_tr_stored_block(s, buf: (char*)0, stored_len: 0L, last: 0); |
1019 | /* For a full flush, this empty block will be recognized |
1020 | * as a special marker by inflate_sync(). |
1021 | */ |
1022 | if (flush == Z_FULL_FLUSH) { |
1023 | CLEAR_HASH(s); /* forget history */ |
1024 | if (s->lookahead == 0) { |
1025 | s->strstart = 0; |
1026 | s->block_start = 0; |
1027 | s->insert = 0; |
1028 | } |
1029 | } |
1030 | } |
1031 | flush_pending(strm); |
1032 | if (strm->avail_out == 0) { |
1033 | s->last_flush = -1; /* avoid BUF_ERROR at next call, see above */ |
1034 | return Z_OK; |
1035 | } |
1036 | } |
1037 | } |
1038 | |
1039 | if (flush != Z_FINISH) |
1040 | return Z_OK; |
1041 | |
1042 | /* Write the trailer */ |
1043 | #ifdef GZIP |
1044 | if (s->wrap == 2) { |
1045 | # ifdef X86_PCLMULQDQ_CRC |
1046 | crc_finalize(s); |
1047 | # endif |
1048 | put_uint32(s, dw: strm->adler); |
1049 | put_uint32(s, dw: (uint32_t)strm->total_in); |
1050 | } else |
1051 | #endif |
1052 | if (s->wrap == 1) |
1053 | put_uint32_msb(s, dw: strm->adler); |
1054 | flush_pending(strm); |
1055 | /* If avail_out is zero, the application will call deflate again |
1056 | * to flush the rest. |
1057 | */ |
1058 | if (s->wrap > 0) |
1059 | s->wrap = -s->wrap; /* write the trailer only once! */ |
1060 | if (s->pending == 0) { |
1061 | Assert(s->bi_valid == 0, "bi_buf not flushed" ); |
1062 | return Z_STREAM_END; |
1063 | } |
1064 | return Z_OK; |
1065 | } |
1066 | |
1067 | /* ========================================================================= */ |
1068 | int32_t Z_EXPORT PREFIX(deflateEnd)(PREFIX3(stream) *strm) { |
1069 | int32_t status; |
1070 | |
1071 | if (deflateStateCheck(strm)) |
1072 | return Z_STREAM_ERROR; |
1073 | |
1074 | status = strm->state->status; |
1075 | |
1076 | /* Deallocate in reverse order of allocations: */ |
1077 | TRY_FREE(strm, strm->state->pending_buf); |
1078 | TRY_FREE(strm, strm->state->head); |
1079 | TRY_FREE(strm, strm->state->prev); |
1080 | TRY_FREE_WINDOW(strm, strm->state->window); |
1081 | |
1082 | ZFREE_STATE(strm, strm->state); |
1083 | strm->state = NULL; |
1084 | |
1085 | return status == BUSY_STATE ? Z_DATA_ERROR : Z_OK; |
1086 | } |
1087 | |
1088 | /* ========================================================================= |
1089 | * Copy the source state to the destination state. |
1090 | */ |
1091 | int32_t Z_EXPORT PREFIX(deflateCopy)(PREFIX3(stream) *dest, PREFIX3(stream) *source) { |
1092 | deflate_state *ds; |
1093 | deflate_state *ss; |
1094 | uint32_t window_padding = 0; |
1095 | |
1096 | if (deflateStateCheck(strm: source) || dest == NULL) |
1097 | return Z_STREAM_ERROR; |
1098 | |
1099 | ss = source->state; |
1100 | |
1101 | memcpy(dest: (void *)dest, src: (void *)source, n: sizeof(PREFIX3(stream))); |
1102 | |
1103 | ds = (deflate_state *) ZALLOC_STATE(dest, 1, sizeof(deflate_state)); |
1104 | if (ds == NULL) |
1105 | return Z_MEM_ERROR; |
1106 | dest->state = (struct internal_state *) ds; |
1107 | ZCOPY_STATE((void *)ds, (void *)ss, sizeof(deflate_state)); |
1108 | ds->strm = dest; |
1109 | |
1110 | #ifdef X86_PCLMULQDQ_CRC |
1111 | window_padding = 8; |
1112 | #endif |
1113 | |
1114 | ds->window = (unsigned char *) ZALLOC_WINDOW(dest, ds->w_size + window_padding, 2*sizeof(unsigned char)); |
1115 | ds->prev = (Pos *) ZALLOC(dest, ds->w_size, sizeof(Pos)); |
1116 | ds->head = (Pos *) ZALLOC(dest, HASH_SIZE, sizeof(Pos)); |
1117 | ds->pending_buf = (unsigned char *) ZALLOC(dest, ds->lit_bufsize, 4); |
1118 | |
1119 | if (ds->window == NULL || ds->prev == NULL || ds->head == NULL || ds->pending_buf == NULL) { |
1120 | PREFIX(deflateEnd)(strm: dest); |
1121 | return Z_MEM_ERROR; |
1122 | } |
1123 | |
1124 | memcpy(dest: ds->window, src: ss->window, n: ds->w_size * 2 * sizeof(unsigned char)); |
1125 | memcpy(dest: (void *)ds->prev, src: (void *)ss->prev, n: ds->w_size * sizeof(Pos)); |
1126 | memcpy(dest: (void *)ds->head, src: (void *)ss->head, HASH_SIZE * sizeof(Pos)); |
1127 | memcpy(dest: ds->pending_buf, src: ss->pending_buf, n: ds->pending_buf_size); |
1128 | |
1129 | ds->pending_out = ds->pending_buf + (ss->pending_out - ss->pending_buf); |
1130 | ds->sym_buf = ds->pending_buf + ds->lit_bufsize; |
1131 | |
1132 | ds->l_desc.dyn_tree = ds->dyn_ltree; |
1133 | ds->d_desc.dyn_tree = ds->dyn_dtree; |
1134 | ds->bl_desc.dyn_tree = ds->bl_tree; |
1135 | |
1136 | return Z_OK; |
1137 | } |
1138 | |
1139 | /* =========================================================================== |
1140 | * Read a new buffer from the current input stream, update the adler32 |
1141 | * and total number of bytes read. All deflate() input goes through |
1142 | * this function so some applications may wish to modify it to avoid |
1143 | * allocating a large strm->next_in buffer and copying from it. |
1144 | * (See also flush_pending()). |
1145 | */ |
1146 | Z_INTERNAL unsigned read_buf(PREFIX3(stream) *strm, unsigned char *buf, unsigned size) { |
1147 | uint32_t len = strm->avail_in; |
1148 | |
1149 | if (len > size) |
1150 | len = size; |
1151 | if (len == 0) |
1152 | return 0; |
1153 | |
1154 | strm->avail_in -= len; |
1155 | |
1156 | if (!DEFLATE_NEED_CHECKSUM(strm)) { |
1157 | memcpy(dest: buf, src: strm->next_in, n: len); |
1158 | #ifdef GZIP |
1159 | } else if (strm->state->wrap == 2) { |
1160 | copy_with_crc(strm, dst: buf, size: len); |
1161 | #endif |
1162 | } else { |
1163 | memcpy(dest: buf, src: strm->next_in, n: len); |
1164 | if (strm->state->wrap == 1) |
1165 | strm->adler = functable.adler32(strm->adler, buf, len); |
1166 | } |
1167 | strm->next_in += len; |
1168 | strm->total_in += len; |
1169 | |
1170 | return len; |
1171 | } |
1172 | |
1173 | /* =========================================================================== |
1174 | * Initialize the "longest match" routines for a new zlib stream |
1175 | */ |
1176 | static void lm_init(deflate_state *s) { |
1177 | s->window_size = 2 * s->w_size; |
1178 | |
1179 | CLEAR_HASH(s); |
1180 | |
1181 | /* Set the default configuration parameters: |
1182 | */ |
1183 | s->max_lazy_match = configuration_table[s->level].max_lazy; |
1184 | s->good_match = configuration_table[s->level].good_length; |
1185 | s->nice_match = configuration_table[s->level].nice_length; |
1186 | s->max_chain_length = configuration_table[s->level].max_chain; |
1187 | |
1188 | s->strstart = 0; |
1189 | s->block_start = 0; |
1190 | s->lookahead = 0; |
1191 | s->insert = 0; |
1192 | s->prev_length = MIN_MATCH-1; |
1193 | s->match_available = 0; |
1194 | s->match_start = 0; |
1195 | } |
1196 | |
1197 | #ifdef ZLIB_DEBUG |
1198 | #define EQUAL 0 |
1199 | /* result of memcmp for equal strings */ |
1200 | |
1201 | /* =========================================================================== |
1202 | * Check that the match at match_start is indeed a match. |
1203 | */ |
1204 | void check_match(deflate_state *s, Pos start, Pos match, int length) { |
1205 | /* check that the match length is valid*/ |
1206 | if (length < MIN_MATCH || length > MAX_MATCH) { |
1207 | fprintf(stderr, " start %u, match %u, length %d\n" , start, match, length); |
1208 | z_error("invalid match length" ); |
1209 | } |
1210 | /* check that the match isn't at the same position as the start string */ |
1211 | if (match == start) { |
1212 | fprintf(stderr, " start %u, match %u, length %d\n" , start, match, length); |
1213 | z_error("invalid match position" ); |
1214 | } |
1215 | /* check that the match is indeed a match */ |
1216 | if (memcmp(s->window + match, s->window + start, length) != EQUAL) { |
1217 | int32_t i = 0; |
1218 | fprintf(stderr, " start %u, match %u, length %d\n" , start, match, length); |
1219 | do { |
1220 | fprintf(stderr, " %03d: match [%02x] start [%02x]\n" , i++, s->window[match++], s->window[start++]); |
1221 | } while (--length != 0); |
1222 | z_error("invalid match" ); |
1223 | } |
1224 | if (z_verbose > 1) { |
1225 | fprintf(stderr, "\\[%u,%d]" , start-match, length); |
1226 | do { |
1227 | putc(s->window[start++], stderr); |
1228 | } while (--length != 0); |
1229 | } |
1230 | } |
1231 | #else |
1232 | # define check_match(s, start, match, length) |
1233 | #endif /* ZLIB_DEBUG */ |
1234 | |
1235 | /* =========================================================================== |
1236 | * Fill the window when the lookahead becomes insufficient. |
1237 | * Updates strstart and lookahead. |
1238 | * |
1239 | * IN assertion: lookahead < MIN_LOOKAHEAD |
1240 | * OUT assertions: strstart <= window_size-MIN_LOOKAHEAD |
1241 | * At least one byte has been read, or avail_in == 0; reads are |
1242 | * performed for at least two bytes (required for the zip translate_eol |
1243 | * option -- not supported here). |
1244 | */ |
1245 | |
1246 | void Z_INTERNAL fill_window(deflate_state *s) { |
1247 | unsigned n; |
1248 | unsigned int more; /* Amount of free space at the end of the window. */ |
1249 | unsigned int wsize = s->w_size; |
1250 | |
1251 | Assert(s->lookahead < MIN_LOOKAHEAD, "already enough lookahead" ); |
1252 | |
1253 | do { |
1254 | more = s->window_size - s->lookahead - s->strstart; |
1255 | |
1256 | /* If the window is almost full and there is insufficient lookahead, |
1257 | * move the upper half to the lower one to make room in the upper half. |
1258 | */ |
1259 | if (s->strstart >= wsize+MAX_DIST(s)) { |
1260 | memcpy(dest: s->window, src: s->window+wsize, n: (unsigned)wsize); |
1261 | if (s->match_start >= wsize) { |
1262 | s->match_start -= wsize; |
1263 | } else { |
1264 | s->match_start = 0; |
1265 | s->prev_length = 0; |
1266 | } |
1267 | s->strstart -= wsize; /* we now have strstart >= MAX_DIST */ |
1268 | s->block_start -= (int)wsize; |
1269 | if (s->insert > s->strstart) |
1270 | s->insert = s->strstart; |
1271 | functable.slide_hash(s); |
1272 | more += wsize; |
1273 | } |
1274 | if (s->strm->avail_in == 0) |
1275 | break; |
1276 | |
1277 | /* If there was no sliding: |
1278 | * strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 && |
1279 | * more == window_size - lookahead - strstart |
1280 | * => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1) |
1281 | * => more >= window_size - 2*WSIZE + 2 |
1282 | * In the BIG_MEM or MMAP case (not yet supported), |
1283 | * window_size == input_size + MIN_LOOKAHEAD && |
1284 | * strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD. |
1285 | * Otherwise, window_size == 2*WSIZE so more >= 2. |
1286 | * If there was sliding, more >= WSIZE. So in all cases, more >= 2. |
1287 | */ |
1288 | Assert(more >= 2, "more < 2" ); |
1289 | |
1290 | n = read_buf(strm: s->strm, buf: s->window + s->strstart + s->lookahead, size: more); |
1291 | s->lookahead += n; |
1292 | |
1293 | /* Initialize the hash value now that we have some input: */ |
1294 | if (s->lookahead + s->insert >= MIN_MATCH) { |
1295 | unsigned int str = s->strstart - s->insert; |
1296 | if (str >= 1) |
1297 | functable.quick_insert_string(s, str + 2 - MIN_MATCH); |
1298 | #if MIN_MATCH != 3 |
1299 | #error Call insert_string() MIN_MATCH-3 more times |
1300 | while (s->insert) { |
1301 | functable.quick_insert_string(s, str); |
1302 | str++; |
1303 | s->insert--; |
1304 | if (s->lookahead + s->insert < MIN_MATCH) |
1305 | break; |
1306 | } |
1307 | #else |
1308 | unsigned int count; |
1309 | if (UNLIKELY(s->lookahead == 1)) { |
1310 | count = s->insert - 1; |
1311 | } else { |
1312 | count = s->insert; |
1313 | } |
1314 | if (count > 0) { |
1315 | functable.insert_string(s, str, count); |
1316 | s->insert -= count; |
1317 | } |
1318 | #endif |
1319 | } |
1320 | /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage, |
1321 | * but this is not important since only literal bytes will be emitted. |
1322 | */ |
1323 | } while (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0); |
1324 | |
1325 | /* If the WIN_INIT bytes after the end of the current data have never been |
1326 | * written, then zero those bytes in order to avoid memory check reports of |
1327 | * the use of uninitialized (or uninitialised as Julian writes) bytes by |
1328 | * the longest match routines. Update the high water mark for the next |
1329 | * time through here. WIN_INIT is set to MAX_MATCH since the longest match |
1330 | * routines allow scanning to strstart + MAX_MATCH, ignoring lookahead. |
1331 | */ |
1332 | if (s->high_water < s->window_size) { |
1333 | unsigned int curr = s->strstart + s->lookahead; |
1334 | unsigned int init; |
1335 | |
1336 | if (s->high_water < curr) { |
1337 | /* Previous high water mark below current data -- zero WIN_INIT |
1338 | * bytes or up to end of window, whichever is less. |
1339 | */ |
1340 | init = s->window_size - curr; |
1341 | if (init > WIN_INIT) |
1342 | init = WIN_INIT; |
1343 | memset(s: s->window + curr, c: 0, n: init); |
1344 | s->high_water = curr + init; |
1345 | } else if (s->high_water < curr + WIN_INIT) { |
1346 | /* High water mark at or above current data, but below current data |
1347 | * plus WIN_INIT -- zero out to current data plus WIN_INIT, or up |
1348 | * to end of window, whichever is less. |
1349 | */ |
1350 | init = curr + WIN_INIT - s->high_water; |
1351 | if (init > s->window_size - s->high_water) |
1352 | init = s->window_size - s->high_water; |
1353 | memset(s: s->window + s->high_water, c: 0, n: init); |
1354 | s->high_water += init; |
1355 | } |
1356 | } |
1357 | |
1358 | Assert((unsigned long)s->strstart <= s->window_size - MIN_LOOKAHEAD, |
1359 | "not enough room for search" ); |
1360 | } |
1361 | |
1362 | /* =========================================================================== |
1363 | * Copy without compression as much as possible from the input stream, return |
1364 | * the current block state. |
1365 | * |
1366 | * In case deflateParams() is used to later switch to a non-zero compression |
1367 | * level, s->matches (otherwise unused when storing) keeps track of the number |
1368 | * of hash table slides to perform. If s->matches is 1, then one hash table |
1369 | * slide will be done when switching. If s->matches is 2, the maximum value |
1370 | * allowed here, then the hash table will be cleared, since two or more slides |
1371 | * is the same as a clear. |
1372 | * |
1373 | * deflate_stored() is written to minimize the number of times an input byte is |
1374 | * copied. It is most efficient with large input and output buffers, which |
1375 | * maximizes the opportunites to have a single copy from next_in to next_out. |
1376 | */ |
1377 | static block_state deflate_stored(deflate_state *s, int flush) { |
1378 | /* Smallest worthy block size when not flushing or finishing. By default |
1379 | * this is 32K. This can be as small as 507 bytes for memLevel == 1. For |
1380 | * large input and output buffers, the stored block size will be larger. |
1381 | */ |
1382 | unsigned min_block = MIN(s->pending_buf_size - 5, s->w_size); |
1383 | |
1384 | /* Copy as many min_block or larger stored blocks directly to next_out as |
1385 | * possible. If flushing, copy the remaining available input to next_out as |
1386 | * stored blocks, if there is enough space. |
1387 | */ |
1388 | unsigned len, left, have, last = 0; |
1389 | unsigned used = s->strm->avail_in; |
1390 | do { |
1391 | /* Set len to the maximum size block that we can copy directly with the |
1392 | * available input data and output space. Set left to how much of that |
1393 | * would be copied from what's left in the window. |
1394 | */ |
1395 | len = MAX_STORED; /* maximum deflate stored block length */ |
1396 | have = (s->bi_valid + 42) >> 3; /* number of header bytes */ |
1397 | if (s->strm->avail_out < have) /* need room for header */ |
1398 | break; |
1399 | /* maximum stored block length that will fit in avail_out: */ |
1400 | have = s->strm->avail_out - have; |
1401 | left = (int)s->strstart - s->block_start; /* bytes left in window */ |
1402 | if (len > (unsigned long)left + s->strm->avail_in) |
1403 | len = left + s->strm->avail_in; /* limit len to the input */ |
1404 | if (len > have) |
1405 | len = have; /* limit len to the output */ |
1406 | |
1407 | /* If the stored block would be less than min_block in length, or if |
1408 | * unable to copy all of the available input when flushing, then try |
1409 | * copying to the window and the pending buffer instead. Also don't |
1410 | * write an empty block when flushing -- deflate() does that. |
1411 | */ |
1412 | if (len < min_block && ((len == 0 && flush != Z_FINISH) || flush == Z_NO_FLUSH || len != left + s->strm->avail_in)) |
1413 | break; |
1414 | |
1415 | /* Make a dummy stored block in pending to get the header bytes, |
1416 | * including any pending bits. This also updates the debugging counts. |
1417 | */ |
1418 | last = flush == Z_FINISH && len == left + s->strm->avail_in ? 1 : 0; |
1419 | zng_tr_stored_block(s, buf: (char *)0, stored_len: 0L, last); |
1420 | |
1421 | /* Replace the lengths in the dummy stored block with len. */ |
1422 | s->pending -= 4; |
1423 | put_short(s, w: (uint16_t)len); |
1424 | put_short(s, w: (uint16_t)~len); |
1425 | |
1426 | /* Write the stored block header bytes. */ |
1427 | flush_pending(strm: s->strm); |
1428 | |
1429 | /* Update debugging counts for the data about to be copied. */ |
1430 | cmpr_bits_add(s, len << 3); |
1431 | sent_bits_add(s, len << 3); |
1432 | |
1433 | /* Copy uncompressed bytes from the window to next_out. */ |
1434 | if (left) { |
1435 | if (left > len) |
1436 | left = len; |
1437 | memcpy(dest: s->strm->next_out, src: s->window + s->block_start, n: left); |
1438 | s->strm->next_out += left; |
1439 | s->strm->avail_out -= left; |
1440 | s->strm->total_out += left; |
1441 | s->block_start += (int)left; |
1442 | len -= left; |
1443 | } |
1444 | |
1445 | /* Copy uncompressed bytes directly from next_in to next_out, updating |
1446 | * the check value. |
1447 | */ |
1448 | if (len) { |
1449 | read_buf(strm: s->strm, buf: s->strm->next_out, size: len); |
1450 | s->strm->next_out += len; |
1451 | s->strm->avail_out -= len; |
1452 | s->strm->total_out += len; |
1453 | } |
1454 | } while (last == 0); |
1455 | |
1456 | /* Update the sliding window with the last s->w_size bytes of the copied |
1457 | * data, or append all of the copied data to the existing window if less |
1458 | * than s->w_size bytes were copied. Also update the number of bytes to |
1459 | * insert in the hash tables, in the event that deflateParams() switches to |
1460 | * a non-zero compression level. |
1461 | */ |
1462 | used -= s->strm->avail_in; /* number of input bytes directly copied */ |
1463 | if (used) { |
1464 | /* If any input was used, then no unused input remains in the window, |
1465 | * therefore s->block_start == s->strstart. |
1466 | */ |
1467 | if (used >= s->w_size) { /* supplant the previous history */ |
1468 | s->matches = 2; /* clear hash */ |
1469 | memcpy(dest: s->window, src: s->strm->next_in - s->w_size, n: s->w_size); |
1470 | s->strstart = s->w_size; |
1471 | s->insert = s->strstart; |
1472 | } else { |
1473 | if (s->window_size - s->strstart <= used) { |
1474 | /* Slide the window down. */ |
1475 | s->strstart -= s->w_size; |
1476 | memcpy(dest: s->window, src: s->window + s->w_size, n: s->strstart); |
1477 | if (s->matches < 2) |
1478 | s->matches++; /* add a pending slide_hash() */ |
1479 | if (s->insert > s->strstart) |
1480 | s->insert = s->strstart; |
1481 | } |
1482 | memcpy(dest: s->window + s->strstart, src: s->strm->next_in - used, n: used); |
1483 | s->strstart += used; |
1484 | s->insert += MIN(used, s->w_size - s->insert); |
1485 | } |
1486 | s->block_start = (int)s->strstart; |
1487 | } |
1488 | if (s->high_water < s->strstart) |
1489 | s->high_water = s->strstart; |
1490 | |
1491 | /* If the last block was written to next_out, then done. */ |
1492 | if (last) |
1493 | return finish_done; |
1494 | |
1495 | /* If flushing and all input has been consumed, then done. */ |
1496 | if (flush != Z_NO_FLUSH && flush != Z_FINISH && s->strm->avail_in == 0 && (int)s->strstart == s->block_start) |
1497 | return block_done; |
1498 | |
1499 | /* Fill the window with any remaining input. */ |
1500 | have = s->window_size - s->strstart; |
1501 | if (s->strm->avail_in > have && s->block_start >= (int)s->w_size) { |
1502 | /* Slide the window down. */ |
1503 | s->block_start -= (int)s->w_size; |
1504 | s->strstart -= s->w_size; |
1505 | memcpy(dest: s->window, src: s->window + s->w_size, n: s->strstart); |
1506 | if (s->matches < 2) |
1507 | s->matches++; /* add a pending slide_hash() */ |
1508 | have += s->w_size; /* more space now */ |
1509 | if (s->insert > s->strstart) |
1510 | s->insert = s->strstart; |
1511 | } |
1512 | if (have > s->strm->avail_in) |
1513 | have = s->strm->avail_in; |
1514 | if (have) { |
1515 | read_buf(strm: s->strm, buf: s->window + s->strstart, size: have); |
1516 | s->strstart += have; |
1517 | s->insert += MIN(have, s->w_size - s->insert); |
1518 | } |
1519 | if (s->high_water < s->strstart) |
1520 | s->high_water = s->strstart; |
1521 | |
1522 | /* There was not enough avail_out to write a complete worthy or flushed |
1523 | * stored block to next_out. Write a stored block to pending instead, if we |
1524 | * have enough input for a worthy block, or if flushing and there is enough |
1525 | * room for the remaining input as a stored block in the pending buffer. |
1526 | */ |
1527 | have = (s->bi_valid + 42) >> 3; /* number of header bytes */ |
1528 | /* maximum stored block length that will fit in pending: */ |
1529 | have = MIN(s->pending_buf_size - have, MAX_STORED); |
1530 | min_block = MIN(have, s->w_size); |
1531 | left = (int)s->strstart - s->block_start; |
1532 | if (left >= min_block || ((left || flush == Z_FINISH) && flush != Z_NO_FLUSH && s->strm->avail_in == 0 && left <= have)) { |
1533 | len = MIN(left, have); |
1534 | last = flush == Z_FINISH && s->strm->avail_in == 0 && len == left ? 1 : 0; |
1535 | zng_tr_stored_block(s, buf: (char *)s->window + s->block_start, stored_len: len, last); |
1536 | s->block_start += (int)len; |
1537 | flush_pending(strm: s->strm); |
1538 | } |
1539 | |
1540 | /* We've done all we can with the available input and output. */ |
1541 | return last ? finish_started : need_more; |
1542 | } |
1543 | |
1544 | |
1545 | /* =========================================================================== |
1546 | * For Z_RLE, simply look for runs of bytes, generate matches only of distance |
1547 | * one. Do not maintain a hash table. (It will be regenerated if this run of |
1548 | * deflate switches away from Z_RLE.) |
1549 | */ |
1550 | static block_state deflate_rle(deflate_state *s, int flush) { |
1551 | int bflush = 0; /* set if current block must be flushed */ |
1552 | unsigned int prev; /* byte at distance one to match */ |
1553 | unsigned char *scan, *strend; /* scan goes up to strend for length of run */ |
1554 | uint32_t match_len = 0; |
1555 | |
1556 | for (;;) { |
1557 | /* Make sure that we always have enough lookahead, except |
1558 | * at the end of the input file. We need MAX_MATCH bytes |
1559 | * for the longest run, plus one for the unrolled loop. |
1560 | */ |
1561 | if (s->lookahead <= MAX_MATCH) { |
1562 | fill_window(s); |
1563 | if (s->lookahead <= MAX_MATCH && flush == Z_NO_FLUSH) |
1564 | return need_more; |
1565 | if (s->lookahead == 0) |
1566 | break; /* flush the current block */ |
1567 | } |
1568 | |
1569 | /* See how many times the previous byte repeats */ |
1570 | if (s->lookahead >= MIN_MATCH && s->strstart > 0) { |
1571 | scan = s->window + s->strstart - 1; |
1572 | prev = *scan; |
1573 | if (prev == *++scan && prev == *++scan && prev == *++scan) { |
1574 | strend = s->window + s->strstart + MAX_MATCH; |
1575 | do { |
1576 | } while (prev == *++scan && prev == *++scan && |
1577 | prev == *++scan && prev == *++scan && |
1578 | prev == *++scan && prev == *++scan && |
1579 | prev == *++scan && prev == *++scan && |
1580 | scan < strend); |
1581 | match_len = MAX_MATCH - (unsigned int)(strend - scan); |
1582 | if (match_len > s->lookahead) |
1583 | match_len = s->lookahead; |
1584 | } |
1585 | Assert(scan <= s->window + s->window_size - 1, "wild scan" ); |
1586 | } |
1587 | |
1588 | /* Emit match if have run of MIN_MATCH or longer, else emit literal */ |
1589 | if (match_len >= MIN_MATCH) { |
1590 | check_match(s, s->strstart, s->strstart - 1, match_len); |
1591 | |
1592 | bflush = zng_tr_tally_dist(s, dist: 1, len: match_len - MIN_MATCH); |
1593 | |
1594 | s->lookahead -= match_len; |
1595 | s->strstart += match_len; |
1596 | match_len = 0; |
1597 | } else { |
1598 | /* No match, output a literal byte */ |
1599 | bflush = zng_tr_tally_lit(s, c: s->window[s->strstart]); |
1600 | s->lookahead--; |
1601 | s->strstart++; |
1602 | } |
1603 | if (bflush) |
1604 | FLUSH_BLOCK(s, 0); |
1605 | } |
1606 | s->insert = 0; |
1607 | if (flush == Z_FINISH) { |
1608 | FLUSH_BLOCK(s, 1); |
1609 | return finish_done; |
1610 | } |
1611 | if (s->sym_next) |
1612 | FLUSH_BLOCK(s, 0); |
1613 | return block_done; |
1614 | } |
1615 | |
1616 | /* =========================================================================== |
1617 | * For Z_HUFFMAN_ONLY, do not look for matches. Do not maintain a hash table. |
1618 | * (It will be regenerated if this run of deflate switches away from Huffman.) |
1619 | */ |
1620 | static block_state deflate_huff(deflate_state *s, int flush) { |
1621 | int bflush = 0; /* set if current block must be flushed */ |
1622 | |
1623 | for (;;) { |
1624 | /* Make sure that we have a literal to write. */ |
1625 | if (s->lookahead == 0) { |
1626 | fill_window(s); |
1627 | if (s->lookahead == 0) { |
1628 | if (flush == Z_NO_FLUSH) |
1629 | return need_more; |
1630 | break; /* flush the current block */ |
1631 | } |
1632 | } |
1633 | |
1634 | /* Output a literal byte */ |
1635 | bflush = zng_tr_tally_lit(s, c: s->window[s->strstart]); |
1636 | s->lookahead--; |
1637 | s->strstart++; |
1638 | if (bflush) |
1639 | FLUSH_BLOCK(s, 0); |
1640 | } |
1641 | s->insert = 0; |
1642 | if (flush == Z_FINISH) { |
1643 | FLUSH_BLOCK(s, 1); |
1644 | return finish_done; |
1645 | } |
1646 | if (s->sym_next) |
1647 | FLUSH_BLOCK(s, 0); |
1648 | return block_done; |
1649 | } |
1650 | |
1651 | #ifndef ZLIB_COMPAT |
1652 | /* ========================================================================= |
1653 | * Checks whether buffer size is sufficient and whether this parameter is a duplicate. |
1654 | */ |
1655 | static int32_t deflateSetParamPre(zng_deflate_param_value **out, size_t min_size, zng_deflate_param_value *param) { |
1656 | int32_t buf_error = param->size < min_size; |
1657 | |
1658 | if (*out != NULL) { |
1659 | (*out)->status = Z_BUF_ERROR; |
1660 | buf_error = 1; |
1661 | } |
1662 | *out = param; |
1663 | return buf_error; |
1664 | } |
1665 | |
1666 | /* ========================================================================= */ |
1667 | int32_t Z_EXPORT zng_deflateSetParams(zng_stream *strm, zng_deflate_param_value *params, size_t count) { |
1668 | size_t i; |
1669 | deflate_state *s; |
1670 | zng_deflate_param_value *new_level = NULL; |
1671 | zng_deflate_param_value *new_strategy = NULL; |
1672 | zng_deflate_param_value *new_reproducible = NULL; |
1673 | int param_buf_error; |
1674 | int version_error = 0; |
1675 | int buf_error = 0; |
1676 | int stream_error = 0; |
1677 | int ret; |
1678 | int val; |
1679 | |
1680 | /* Initialize the statuses. */ |
1681 | for (i = 0; i < count; i++) |
1682 | params[i].status = Z_OK; |
1683 | |
1684 | /* Check whether the stream state is consistent. */ |
1685 | if (deflateStateCheck(strm)) |
1686 | return Z_STREAM_ERROR; |
1687 | s = strm->state; |
1688 | |
1689 | /* Check buffer sizes and detect duplicates. */ |
1690 | for (i = 0; i < count; i++) { |
1691 | switch (params[i].param) { |
1692 | case Z_DEFLATE_LEVEL: |
1693 | param_buf_error = deflateSetParamPre(&new_level, sizeof(int), ¶ms[i]); |
1694 | break; |
1695 | case Z_DEFLATE_STRATEGY: |
1696 | param_buf_error = deflateSetParamPre(&new_strategy, sizeof(int), ¶ms[i]); |
1697 | break; |
1698 | case Z_DEFLATE_REPRODUCIBLE: |
1699 | param_buf_error = deflateSetParamPre(&new_reproducible, sizeof(int), ¶ms[i]); |
1700 | break; |
1701 | default: |
1702 | params[i].status = Z_VERSION_ERROR; |
1703 | version_error = 1; |
1704 | param_buf_error = 0; |
1705 | break; |
1706 | } |
1707 | if (param_buf_error) { |
1708 | params[i].status = Z_BUF_ERROR; |
1709 | buf_error = 1; |
1710 | } |
1711 | } |
1712 | /* Exit early if small buffers or duplicates are detected. */ |
1713 | if (buf_error) |
1714 | return Z_BUF_ERROR; |
1715 | |
1716 | /* Apply changes, remember if there were errors. */ |
1717 | if (new_level != NULL || new_strategy != NULL) { |
1718 | ret = PREFIX(deflateParams)(strm, new_level == NULL ? s->level : *(int *)new_level->buf, |
1719 | new_strategy == NULL ? s->strategy : *(int *)new_strategy->buf); |
1720 | if (ret != Z_OK) { |
1721 | if (new_level != NULL) |
1722 | new_level->status = Z_STREAM_ERROR; |
1723 | if (new_strategy != NULL) |
1724 | new_strategy->status = Z_STREAM_ERROR; |
1725 | stream_error = 1; |
1726 | } |
1727 | } |
1728 | if (new_reproducible != NULL) { |
1729 | val = *(int *)new_reproducible->buf; |
1730 | if (DEFLATE_CAN_SET_REPRODUCIBLE(strm, val)) { |
1731 | s->reproducible = val; |
1732 | } else { |
1733 | new_reproducible->status = Z_STREAM_ERROR; |
1734 | stream_error = 1; |
1735 | } |
1736 | } |
1737 | |
1738 | /* Report version errors only if there are no real errors. */ |
1739 | return stream_error ? Z_STREAM_ERROR : (version_error ? Z_VERSION_ERROR : Z_OK); |
1740 | } |
1741 | |
1742 | /* ========================================================================= */ |
1743 | int32_t Z_EXPORT zng_deflateGetParams(zng_stream *strm, zng_deflate_param_value *params, size_t count) { |
1744 | deflate_state *s; |
1745 | size_t i; |
1746 | int32_t buf_error = 0; |
1747 | int32_t version_error = 0; |
1748 | |
1749 | /* Initialize the statuses. */ |
1750 | for (i = 0; i < count; i++) |
1751 | params[i].status = Z_OK; |
1752 | |
1753 | /* Check whether the stream state is consistent. */ |
1754 | if (deflateStateCheck(strm)) |
1755 | return Z_STREAM_ERROR; |
1756 | s = strm->state; |
1757 | |
1758 | for (i = 0; i < count; i++) { |
1759 | switch (params[i].param) { |
1760 | case Z_DEFLATE_LEVEL: |
1761 | if (params[i].size < sizeof(int)) |
1762 | params[i].status = Z_BUF_ERROR; |
1763 | else |
1764 | *(int *)params[i].buf = s->level; |
1765 | break; |
1766 | case Z_DEFLATE_STRATEGY: |
1767 | if (params[i].size < sizeof(int)) |
1768 | params[i].status = Z_BUF_ERROR; |
1769 | else |
1770 | *(int *)params[i].buf = s->strategy; |
1771 | break; |
1772 | case Z_DEFLATE_REPRODUCIBLE: |
1773 | if (params[i].size < sizeof(int)) |
1774 | params[i].status = Z_BUF_ERROR; |
1775 | else |
1776 | *(int *)params[i].buf = s->reproducible; |
1777 | break; |
1778 | default: |
1779 | params[i].status = Z_VERSION_ERROR; |
1780 | version_error = 1; |
1781 | break; |
1782 | } |
1783 | if (params[i].status == Z_BUF_ERROR) |
1784 | buf_error = 1; |
1785 | } |
1786 | return buf_error ? Z_BUF_ERROR : (version_error ? Z_VERSION_ERROR : Z_OK); |
1787 | } |
1788 | #endif |
1789 | |