| 1 | /* |
| 2 | * This file is derived from various .h and .c files from the zlib-0.95 |
| 3 | * distribution by Jean-loup Gailly and Mark Adler, with some additions |
| 4 | * by Paul Mackerras to aid in implementing Deflate compression and |
| 5 | * decompression for PPP packets. See zlib.h for conditions of |
| 6 | * distribution and use. |
| 7 | * |
| 8 | * Changes that have been made include: |
| 9 | * - changed functions not used outside this file to "local" |
| 10 | * - added Z_PACKET_FLUSH (see zlib.h for details) |
| 11 | * - added inflateIncomp |
| 12 | * |
| 13 | * $Id$ |
| 14 | */ |
| 15 | |
| 16 | |
| 17 | /*+++++*/ |
| 18 | /* zutil.h -- internal interface and configuration of the compression library |
| 19 | * Copyright (C) 1995 Jean-loup Gailly. |
| 20 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 21 | */ |
| 22 | |
| 23 | /* WARNING: this file should *not* be used by applications. It is |
| 24 | part of the implementation of the compression library and is |
| 25 | subject to change. Applications should only use zlib.h. |
| 26 | */ |
| 27 | |
| 28 | /* From: zutil.h,v 1.9 1995/05/03 17:27:12 jloup Exp */ |
| 29 | |
| 30 | #define _Z_UTIL_H |
| 31 | |
| 32 | #include "../rsync.h" |
| 33 | #include "zlib.h" |
| 34 | |
| 35 | #ifndef local |
| 36 | # define local static |
| 37 | #endif |
| 38 | /* compile with -Dlocal if your debugger can't find static symbols */ |
| 39 | |
| 40 | #define FAR |
| 41 | |
| 42 | typedef unsigned char uch; |
| 43 | typedef uch FAR uchf; |
| 44 | typedef unsigned short ush; |
| 45 | typedef ush FAR ushf; |
| 46 | typedef unsigned int ulg; |
| 47 | |
| 48 | extern char *z_errmsg[]; /* indexed by 1-zlib_error */ |
| 49 | |
| 50 | #define ERR_RETURN(strm,err) return (strm->msg=z_errmsg[1-err], err) |
| 51 | /* To be used only when the state is known to be valid */ |
| 52 | |
| 53 | #ifndef NULL |
| 54 | #define NULL ((void *) 0) |
| 55 | #endif |
| 56 | |
| 57 | /* common constants */ |
| 58 | |
| 59 | #define DEFLATED 8 |
| 60 | |
| 61 | #ifndef DEF_WBITS |
| 62 | # define DEF_WBITS MAX_WBITS |
| 63 | #endif |
| 64 | /* default windowBits for decompression. MAX_WBITS is for compression only */ |
| 65 | |
| 66 | #if MAX_MEM_LEVEL >= 8 |
| 67 | # define DEF_MEM_LEVEL 8 |
| 68 | #else |
| 69 | # define DEF_MEM_LEVEL MAX_MEM_LEVEL |
| 70 | #endif |
| 71 | /* default memLevel */ |
| 72 | |
| 73 | #define STORED_BLOCK 0 |
| 74 | #define STATIC_TREES 1 |
| 75 | #define DYN_TREES 2 |
| 76 | /* The three kinds of block type */ |
| 77 | |
| 78 | #define MIN_MATCH 3 |
| 79 | #define MAX_MATCH 258 |
| 80 | /* The minimum and maximum match lengths */ |
| 81 | |
| 82 | /* functions */ |
| 83 | #define zmemcpy(d, s, n) bcopy((s), (d), (n)) |
| 84 | #define zmemzero bzero |
| 85 | |
| 86 | /* Diagnostic functions */ |
| 87 | #ifdef DEBUG_ZLIB |
| 88 | # include <stdio.h> |
| 89 | # ifndef verbose |
| 90 | # define verbose 0 |
| 91 | # endif |
| 92 | # define Assert(cond,msg) {if(!(cond)) z_error(msg);} |
| 93 | # define Trace(x) fprintf x |
| 94 | # define Tracev(x) {if (verbose) fprintf x ;} |
| 95 | # define Tracevv(x) {if (verbose>1) fprintf x ;} |
| 96 | # define Tracec(c,x) {if (verbose && (c)) fprintf x ;} |
| 97 | # define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;} |
| 98 | #else |
| 99 | # define Assert(cond,msg) |
| 100 | # define Trace(x) |
| 101 | # define Tracev(x) |
| 102 | # define Tracevv(x) |
| 103 | # define Tracec(c,x) |
| 104 | # define Tracecv(c,x) |
| 105 | #endif |
| 106 | |
| 107 | |
| 108 | typedef uLong (*check_func) OF((uLong check, Bytef *buf, uInt len)); |
| 109 | |
| 110 | /* voidpf zcalloc OF((voidpf opaque, unsigned items, unsigned size)); */ |
| 111 | /* void zcfree OF((voidpf opaque, voidpf ptr)); */ |
| 112 | |
| 113 | #define ZALLOC(strm, items, size) \ |
| 114 | (*((strm)->zalloc))((strm)->opaque, (items), (size)) |
| 115 | #define ZFREE(strm, addr, size) \ |
| 116 | (*((strm)->zfree))((strm)->opaque, (voidpf)(addr), (size)) |
| 117 | #define TRY_FREE(s, p, n) {if (p) ZFREE(s, p, n);} |
| 118 | |
| 119 | /* deflate.h -- internal compression state |
| 120 | * Copyright (C) 1995 Jean-loup Gailly |
| 121 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 122 | */ |
| 123 | |
| 124 | /* WARNING: this file should *not* be used by applications. It is |
| 125 | part of the implementation of the compression library and is |
| 126 | subject to change. Applications should only use zlib.h. |
| 127 | */ |
| 128 | |
| 129 | |
| 130 | /*+++++*/ |
| 131 | /* From: deflate.h,v 1.5 1995/05/03 17:27:09 jloup Exp */ |
| 132 | |
| 133 | /* =========================================================================== |
| 134 | * Internal compression state. |
| 135 | */ |
| 136 | |
| 137 | /* Data type */ |
| 138 | #define BINARY 0 |
| 139 | #define ASCII 1 |
| 140 | #define UNKNOWN 2 |
| 141 | |
| 142 | #define LENGTH_CODES 29 |
| 143 | /* number of length codes, not counting the special END_BLOCK code */ |
| 144 | |
| 145 | #define LITERALS 256 |
| 146 | /* number of literal bytes 0..255 */ |
| 147 | |
| 148 | #define L_CODES (LITERALS+1+LENGTH_CODES) |
| 149 | /* number of Literal or Length codes, including the END_BLOCK code */ |
| 150 | |
| 151 | #define D_CODES 30 |
| 152 | /* number of distance codes */ |
| 153 | |
| 154 | #define BL_CODES 19 |
| 155 | /* number of codes used to transfer the bit lengths */ |
| 156 | |
| 157 | #define HEAP_SIZE (2*L_CODES+1) |
| 158 | /* maximum heap size */ |
| 159 | |
| 160 | #define MAX_BITS 15 |
| 161 | /* All codes must not exceed MAX_BITS bits */ |
| 162 | |
| 163 | #define INIT_STATE 42 |
| 164 | #define BUSY_STATE 113 |
| 165 | #define FLUSH_STATE 124 |
| 166 | #define FINISH_STATE 666 |
| 167 | /* Stream status */ |
| 168 | |
| 169 | |
| 170 | /* Data structure describing a single value and its code string. */ |
| 171 | typedef struct ct_data_s { |
| 172 | union { |
| 173 | ush freq; /* frequency count */ |
| 174 | ush code; /* bit string */ |
| 175 | } fc; |
| 176 | union { |
| 177 | ush dad; /* father node in Huffman tree */ |
| 178 | ush len; /* length of bit string */ |
| 179 | } dl; |
| 180 | } FAR ct_data; |
| 181 | |
| 182 | #define Freq fc.freq |
| 183 | #define Code fc.code |
| 184 | #define Dad dl.dad |
| 185 | #define Len dl.len |
| 186 | |
| 187 | typedef struct static_tree_desc_s static_tree_desc; |
| 188 | |
| 189 | typedef struct tree_desc_s { |
| 190 | ct_data *dyn_tree; /* the dynamic tree */ |
| 191 | int max_code; /* largest code with non zero frequency */ |
| 192 | static_tree_desc *stat_desc; /* the corresponding static tree */ |
| 193 | } FAR tree_desc; |
| 194 | |
| 195 | typedef ush Pos; |
| 196 | typedef Pos FAR Posf; |
| 197 | typedef unsigned IPos; |
| 198 | |
| 199 | /* A Pos is an index in the character window. We use short instead of int to |
| 200 | * save space in the various tables. IPos is used only for parameter passing. |
| 201 | */ |
| 202 | |
| 203 | typedef struct deflate_state { |
| 204 | z_stream *strm; /* pointer back to this zlib stream */ |
| 205 | int status; /* as the name implies */ |
| 206 | Bytef *pending_buf; /* output still pending */ |
| 207 | Bytef *pending_out; /* next pending byte to output to the stream */ |
| 208 | int pending; /* nb of bytes in the pending buffer */ |
| 209 | uLong adler; /* adler32 of uncompressed data */ |
| 210 | int noheader; /* suppress zlib header and adler32 */ |
| 211 | Byte data_type; /* UNKNOWN, BINARY or ASCII */ |
| 212 | Byte method; /* STORED (for zip only) or DEFLATED */ |
| 213 | |
| 214 | /* used by deflate.c: */ |
| 215 | |
| 216 | uInt w_size; /* LZ77 window size (32K by default) */ |
| 217 | uInt w_bits; /* log2(w_size) (8..16) */ |
| 218 | uInt w_mask; /* w_size - 1 */ |
| 219 | |
| 220 | Bytef *window; |
| 221 | /* Sliding window. Input bytes are read into the second half of the window, |
| 222 | * and move to the first half later to keep a dictionary of at least wSize |
| 223 | * bytes. With this organization, matches are limited to a distance of |
| 224 | * wSize-MAX_MATCH bytes, but this ensures that IO is always |
| 225 | * performed with a length multiple of the block size. Also, it limits |
| 226 | * the window size to 64K, which is quite useful on MSDOS. |
| 227 | * To do: use the user input buffer as sliding window. |
| 228 | */ |
| 229 | |
| 230 | ulg window_size; |
| 231 | /* Actual size of window: 2*wSize, except when the user input buffer |
| 232 | * is directly used as sliding window. |
| 233 | */ |
| 234 | |
| 235 | Posf *prev; |
| 236 | /* Link to older string with same hash index. To limit the size of this |
| 237 | * array to 64K, this link is maintained only for the last 32K strings. |
| 238 | * An index in this array is thus a window index modulo 32K. |
| 239 | */ |
| 240 | |
| 241 | Posf *head; /* Heads of the hash chains or NIL. */ |
| 242 | |
| 243 | uInt ins_h; /* hash index of string to be inserted */ |
| 244 | uInt hash_size; /* number of elements in hash table */ |
| 245 | uInt hash_bits; /* log2(hash_size) */ |
| 246 | uInt hash_mask; /* hash_size-1 */ |
| 247 | |
| 248 | uInt hash_shift; |
| 249 | /* Number of bits by which ins_h must be shifted at each input |
| 250 | * step. It must be such that after MIN_MATCH steps, the oldest |
| 251 | * byte no longer takes part in the hash key, that is: |
| 252 | * hash_shift * MIN_MATCH >= hash_bits |
| 253 | */ |
| 254 | |
| 255 | Long block_start; |
| 256 | /* Window position at the beginning of the current output block. Gets |
| 257 | * negative when the window is moved backwards. |
| 258 | */ |
| 259 | |
| 260 | uInt match_length; /* length of best match */ |
| 261 | IPos prev_match; /* previous match */ |
| 262 | int match_available; /* set if previous match exists */ |
| 263 | uInt strstart; /* start of string to insert */ |
| 264 | uInt match_start; /* start of matching string */ |
| 265 | uInt lookahead; /* number of valid bytes ahead in window */ |
| 266 | |
| 267 | uInt prev_length; |
| 268 | /* Length of the best match at previous step. Matches not greater than this |
| 269 | * are discarded. This is used in the lazy match evaluation. |
| 270 | */ |
| 271 | |
| 272 | uInt max_chain_length; |
| 273 | /* To speed up deflation, hash chains are never searched beyond this |
| 274 | * length. A higher limit improves compression ratio but degrades the |
| 275 | * speed. |
| 276 | */ |
| 277 | |
| 278 | uInt max_lazy_match; |
| 279 | /* Attempt to find a better match only when the current match is strictly |
| 280 | * smaller than this value. This mechanism is used only for compression |
| 281 | * levels >= 4. |
| 282 | */ |
| 283 | # define max_insert_length max_lazy_match |
| 284 | /* Insert new strings in the hash table only if the match length is not |
| 285 | * greater than this length. This saves time but degrades compression. |
| 286 | * max_insert_length is used only for compression levels <= 3. |
| 287 | */ |
| 288 | |
| 289 | int level; /* compression level (1..9) */ |
| 290 | int strategy; /* favor or force Huffman coding*/ |
| 291 | |
| 292 | uInt good_match; |
| 293 | /* Use a faster search when the previous match is longer than this */ |
| 294 | |
| 295 | int nice_match; /* Stop searching when current match exceeds this */ |
| 296 | |
| 297 | /* used by trees.c: */ |
| 298 | /* Didn't use ct_data typedef below to supress compiler warning */ |
| 299 | struct ct_data_s dyn_ltree[HEAP_SIZE]; /* literal and length tree */ |
| 300 | struct ct_data_s dyn_dtree[2*D_CODES+1]; /* distance tree */ |
| 301 | struct ct_data_s bl_tree[2*BL_CODES+1]; /* Huffman tree for bit lengths */ |
| 302 | |
| 303 | struct tree_desc_s l_desc; /* desc. for literal tree */ |
| 304 | struct tree_desc_s d_desc; /* desc. for distance tree */ |
| 305 | struct tree_desc_s bl_desc; /* desc. for bit length tree */ |
| 306 | |
| 307 | ush bl_count[MAX_BITS+1]; |
| 308 | /* number of codes at each bit length for an optimal tree */ |
| 309 | |
| 310 | int heap[2*L_CODES+1]; /* heap used to build the Huffman trees */ |
| 311 | int heap_len; /* number of elements in the heap */ |
| 312 | int heap_max; /* element of largest frequency */ |
| 313 | /* The sons of heap[n] are heap[2*n] and heap[2*n+1]. heap[0] is not used. |
| 314 | * The same heap array is used to build all trees. |
| 315 | */ |
| 316 | |
| 317 | uch depth[2*L_CODES+1]; |
| 318 | /* Depth of each subtree used as tie breaker for trees of equal frequency |
| 319 | */ |
| 320 | |
| 321 | uchf *l_buf; /* buffer for literals or lengths */ |
| 322 | |
| 323 | uInt lit_bufsize; |
| 324 | /* Size of match buffer for literals/lengths. There are 4 reasons for |
| 325 | * limiting lit_bufsize to 64K: |
| 326 | * - frequencies can be kept in 16 bit counters |
| 327 | * - if compression is not successful for the first block, all input |
| 328 | * data is still in the window so we can still emit a stored block even |
| 329 | * when input comes from standard input. (This can also be done for |
| 330 | * all blocks if lit_bufsize is not greater than 32K.) |
| 331 | * - if compression is not successful for a file smaller than 64K, we can |
| 332 | * even emit a stored file instead of a stored block (saving 5 bytes). |
| 333 | * This is applicable only for zip (not gzip or zlib). |
| 334 | * - creating new Huffman trees less frequently may not provide fast |
| 335 | * adaptation to changes in the input data statistics. (Take for |
| 336 | * example a binary file with poorly compressible code followed by |
| 337 | * a highly compressible string table.) Smaller buffer sizes give |
| 338 | * fast adaptation but have of course the overhead of transmitting |
| 339 | * trees more frequently. |
| 340 | * - I can't count above 4 |
| 341 | */ |
| 342 | |
| 343 | uInt last_lit; /* running index in l_buf */ |
| 344 | |
| 345 | ushf *d_buf; |
| 346 | /* Buffer for distances. To simplify the code, d_buf and l_buf have |
| 347 | * the same number of elements. To use different lengths, an extra flag |
| 348 | * array would be necessary. |
| 349 | */ |
| 350 | |
| 351 | ulg opt_len; /* bit length of current block with optimal trees */ |
| 352 | ulg static_len; /* bit length of current block with static trees */ |
| 353 | ulg compressed_len; /* total bit length of compressed file */ |
| 354 | uInt matches; /* number of string matches in current block */ |
| 355 | int last_eob_len; /* bit length of EOB code for last block */ |
| 356 | |
| 357 | #ifdef DEBUG_ZLIB |
| 358 | ulg bits_sent; /* bit length of the compressed data */ |
| 359 | #endif |
| 360 | |
| 361 | ush bi_buf; |
| 362 | /* Output buffer. bits are inserted starting at the bottom (least |
| 363 | * significant bits). |
| 364 | */ |
| 365 | int bi_valid; |
| 366 | /* Number of valid bits in bi_buf. All bits above the last valid bit |
| 367 | * are always zero. |
| 368 | */ |
| 369 | |
| 370 | uInt blocks_in_packet; |
| 371 | /* Number of blocks produced since the last time Z_PACKET_FLUSH |
| 372 | * was used. |
| 373 | */ |
| 374 | |
| 375 | } FAR deflate_state; |
| 376 | |
| 377 | /* Output a byte on the stream. |
| 378 | * IN assertion: there is enough room in pending_buf. |
| 379 | */ |
| 380 | #define put_byte(s, c) {s->pending_buf[s->pending++] = (c);} |
| 381 | |
| 382 | |
| 383 | #define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1) |
| 384 | /* Minimum amount of lookahead, except at the end of the input file. |
| 385 | * See deflate.c for comments about the MIN_MATCH+1. |
| 386 | */ |
| 387 | |
| 388 | #define MAX_DIST(s) ((s)->w_size-MIN_LOOKAHEAD) |
| 389 | /* In order to simplify the code, particularly on 16 bit machines, match |
| 390 | * distances are limited to MAX_DIST instead of WSIZE. |
| 391 | */ |
| 392 | |
| 393 | /* in trees.c */ |
| 394 | local void ct_init OF((deflate_state *s)); |
| 395 | local int ct_tally OF((deflate_state *s, int dist, int lc)); |
| 396 | local ulg ct_flush_block OF((deflate_state *s, charf *buf, ulg stored_len, |
| 397 | int flush)); |
| 398 | local void ct_align OF((deflate_state *s)); |
| 399 | local void ct_stored_block OF((deflate_state *s, charf *buf, ulg stored_len, |
| 400 | int eof)); |
| 401 | local void ct_stored_type_only OF((deflate_state *s)); |
| 402 | |
| 403 | |
| 404 | /*+++++*/ |
| 405 | /* deflate.c -- compress data using the deflation algorithm |
| 406 | * Copyright (C) 1995 Jean-loup Gailly. |
| 407 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 408 | */ |
| 409 | |
| 410 | /* |
| 411 | * ALGORITHM |
| 412 | * |
| 413 | * The "deflation" process depends on being able to identify portions |
| 414 | * of the input text which are identical to earlier input (within a |
| 415 | * sliding window trailing behind the input currently being processed). |
| 416 | * |
| 417 | * The most straightforward technique turns out to be the fastest for |
| 418 | * most input files: try all possible matches and select the longest. |
| 419 | * The key feature of this algorithm is that insertions into the string |
| 420 | * dictionary are very simple and thus fast, and deletions are avoided |
| 421 | * completely. Insertions are performed at each input character, whereas |
| 422 | * string matches are performed only when the previous match ends. So it |
| 423 | * is preferable to spend more time in matches to allow very fast string |
| 424 | * insertions and avoid deletions. The matching algorithm for small |
| 425 | * strings is inspired from that of Rabin & Karp. A brute force approach |
| 426 | * is used to find longer strings when a small match has been found. |
| 427 | * A similar algorithm is used in comic (by Jan-Mark Wams) and freeze |
| 428 | * (by Leonid Broukhis). |
| 429 | * A previous version of this file used a more sophisticated algorithm |
| 430 | * (by Fiala and Greene) which is guaranteed to run in linear amortized |
| 431 | * time, but has a larger average cost, uses more memory and is patented. |
| 432 | * However the F&G algorithm may be faster for some highly redundant |
| 433 | * files if the parameter max_chain_length (described below) is too large. |
| 434 | * |
| 435 | * ACKNOWLEDGEMENTS |
| 436 | * |
| 437 | * The idea of lazy evaluation of matches is due to Jan-Mark Wams, and |
| 438 | * I found it in 'freeze' written by Leonid Broukhis. |
| 439 | * Thanks to many people for bug reports and testing. |
| 440 | * |
| 441 | * REFERENCES |
| 442 | * |
| 443 | * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification". |
| 444 | * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc |
| 445 | * |
| 446 | * A description of the Rabin and Karp algorithm is given in the book |
| 447 | * "Algorithms" by R. Sedgewick, Addison-Wesley, p252. |
| 448 | * |
| 449 | * Fiala,E.R., and Greene,D.H. |
| 450 | * Data Compression with Finite Windows, Comm.ACM, 32,4 (1989) 490-595 |
| 451 | * |
| 452 | */ |
| 453 | |
| 454 | /* From: deflate.c,v 1.8 1995/05/03 17:27:08 jloup Exp */ |
| 455 | |
| 456 | char zlib_copyright[] = " deflate Copyright 1995 Jean-loup Gailly "; |
| 457 | /* |
| 458 | If you use the zlib library in a product, an acknowledgment is welcome |
| 459 | in the documentation of your product. If for some reason you cannot |
| 460 | include such an acknowledgment, I would appreciate that you keep this |
| 461 | copyright string in the executable of your product. |
| 462 | */ |
| 463 | |
| 464 | #define NIL 0 |
| 465 | /* Tail of hash chains */ |
| 466 | |
| 467 | #ifndef TOO_FAR |
| 468 | # define TOO_FAR 4096 |
| 469 | #endif |
| 470 | /* Matches of length 3 are discarded if their distance exceeds TOO_FAR */ |
| 471 | |
| 472 | #define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1) |
| 473 | /* Minimum amount of lookahead, except at the end of the input file. |
| 474 | * See deflate.c for comments about the MIN_MATCH+1. |
| 475 | */ |
| 476 | |
| 477 | /* Values for max_lazy_match, good_match and max_chain_length, depending on |
| 478 | * the desired pack level (0..9). The values given below have been tuned to |
| 479 | * exclude worst case performance for pathological files. Better values may be |
| 480 | * found for specific files. |
| 481 | */ |
| 482 | |
| 483 | typedef struct config_s { |
| 484 | ush good_length; /* reduce lazy search above this match length */ |
| 485 | ush max_lazy; /* do not perform lazy search above this match length */ |
| 486 | ush nice_length; /* quit search above this match length */ |
| 487 | ush max_chain; |
| 488 | } config; |
| 489 | |
| 490 | local config configuration_table[10] = { |
| 491 | /* good lazy nice chain */ |
| 492 | /* 0 */ {0, 0, 0, 0}, /* store only */ |
| 493 | /* 1 */ {4, 4, 8, 4}, /* maximum speed, no lazy matches */ |
| 494 | /* 2 */ {4, 5, 16, 8}, |
| 495 | /* 3 */ {4, 6, 32, 32}, |
| 496 | |
| 497 | /* 4 */ {4, 4, 16, 16}, /* lazy matches */ |
| 498 | /* 5 */ {8, 16, 32, 32}, |
| 499 | /* 6 */ {8, 16, 128, 128}, |
| 500 | /* 7 */ {8, 32, 128, 256}, |
| 501 | /* 8 */ {32, 128, 258, 1024}, |
| 502 | /* 9 */ {32, 258, 258, 4096}}; /* maximum compression */ |
| 503 | |
| 504 | /* Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4 |
| 505 | * For deflate_fast() (levels <= 3) good is ignored and lazy has a different |
| 506 | * meaning. |
| 507 | */ |
| 508 | |
| 509 | #define EQUAL 0 |
| 510 | /* result of memcmp for equal strings */ |
| 511 | |
| 512 | /* =========================================================================== |
| 513 | * Prototypes for local functions. |
| 514 | */ |
| 515 | |
| 516 | local void fill_window OF((deflate_state *s)); |
| 517 | local int deflate_fast OF((deflate_state *s, int flush)); |
| 518 | local int deflate_slow OF((deflate_state *s, int flush)); |
| 519 | local void lm_init OF((deflate_state *s)); |
| 520 | local int longest_match OF((deflate_state *s, IPos cur_match)); |
| 521 | local void putShortMSB OF((deflate_state *s, uInt b)); |
| 522 | local void flush_pending OF((z_stream *strm)); |
| 523 | local int zread_buf OF((z_stream *strm, charf *buf, unsigned size)); |
| 524 | #ifdef ASMV |
| 525 | void match_init OF((void)); /* asm code initialization */ |
| 526 | #endif |
| 527 | |
| 528 | #ifdef DEBUG_ZLIB |
| 529 | local void check_match OF((deflate_state *s, IPos start, IPos match, |
| 530 | int length)); |
| 531 | #endif |
| 532 | |
| 533 | |
| 534 | /* =========================================================================== |
| 535 | * Update a hash value with the given input byte |
| 536 | * IN assertion: all calls to to UPDATE_HASH are made with consecutive |
| 537 | * input characters, so that a running hash key can be computed from the |
| 538 | * previous key instead of complete recalculation each time. |
| 539 | */ |
| 540 | #define UPDATE_HASH(s,h,c) (h = (((h)<<s->hash_shift) ^ (c)) & s->hash_mask) |
| 541 | |
| 542 | |
| 543 | /* =========================================================================== |
| 544 | * Insert string str in the dictionary and set match_head to the previous head |
| 545 | * of the hash chain (the most recent string with same hash key). Return |
| 546 | * the previous length of the hash chain. |
| 547 | * IN assertion: all calls to to INSERT_STRING are made with consecutive |
| 548 | * input characters and the first MIN_MATCH bytes of str are valid |
| 549 | * (except for the last MIN_MATCH-1 bytes of the input file). |
| 550 | */ |
| 551 | #define INSERT_STRING(s, str, match_head) \ |
| 552 | (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \ |
| 553 | s->prev[(str) & s->w_mask] = match_head = s->head[s->ins_h], \ |
| 554 | s->head[s->ins_h] = (str)) |
| 555 | |
| 556 | /* =========================================================================== |
| 557 | * Initialize the hash table (avoiding 64K overflow for 16 bit systems). |
| 558 | * prev[] will be initialized on the fly. |
| 559 | */ |
| 560 | #define CLEAR_HASH(s) \ |
| 561 | s->head[s->hash_size-1] = NIL; \ |
| 562 | zmemzero((charf *)s->head, (unsigned)(s->hash_size-1)*sizeof(*s->head)); |
| 563 | |
| 564 | /* ========================================================================= */ |
| 565 | int deflateInit (strm, level) |
| 566 | z_stream *strm; |
| 567 | int level; |
| 568 | { |
| 569 | return deflateInit2 (strm, level, DEFLATED, MAX_WBITS, DEF_MEM_LEVEL, 0); |
| 570 | /* To do: ignore strm->next_in if we use it as window */ |
| 571 | } |
| 572 | |
| 573 | /* ========================================================================= */ |
| 574 | int deflateInit2 (strm, level, method, windowBits, memLevel, strategy) |
| 575 | z_stream *strm; |
| 576 | int level; |
| 577 | int method; |
| 578 | int windowBits; |
| 579 | int memLevel; |
| 580 | int strategy; |
| 581 | { |
| 582 | deflate_state *s; |
| 583 | int noheader = 0; |
| 584 | |
| 585 | if (strm == Z_NULL) return Z_STREAM_ERROR; |
| 586 | |
| 587 | strm->msg = Z_NULL; |
| 588 | /* if (strm->zalloc == Z_NULL) strm->zalloc = zcalloc; */ |
| 589 | /* if (strm->zfree == Z_NULL) strm->zfree = zcfree; */ |
| 590 | |
| 591 | if (level == Z_DEFAULT_COMPRESSION) level = 6; |
| 592 | |
| 593 | if (windowBits < 0) { /* undocumented feature: suppress zlib header */ |
| 594 | noheader = 1; |
| 595 | windowBits = -windowBits; |
| 596 | } |
| 597 | if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != DEFLATED || |
| 598 | windowBits < 8 || windowBits > 15 || level < 1 || level > 9) { |
| 599 | return Z_STREAM_ERROR; |
| 600 | } |
| 601 | s = (deflate_state *) ZALLOC(strm, 1, sizeof(deflate_state)); |
| 602 | if (s == Z_NULL) return Z_MEM_ERROR; |
| 603 | bzero(s, sizeof(*s)); |
| 604 | strm->state = (struct internal_state FAR *)s; |
| 605 | s->strm = strm; |
| 606 | |
| 607 | s->noheader = noheader; |
| 608 | s->w_bits = windowBits; |
| 609 | s->w_size = 1 << s->w_bits; |
| 610 | s->w_mask = s->w_size - 1; |
| 611 | |
| 612 | s->hash_bits = memLevel + 7; |
| 613 | s->hash_size = 1 << s->hash_bits; |
| 614 | s->hash_mask = s->hash_size - 1; |
| 615 | s->hash_shift = ((s->hash_bits+MIN_MATCH-1)/MIN_MATCH); |
| 616 | |
| 617 | s->window = (Bytef *) ZALLOC(strm, s->w_size, 2*sizeof(Byte)); |
| 618 | s->prev = (Posf *) ZALLOC(strm, s->w_size, sizeof(Pos)); |
| 619 | s->head = (Posf *) ZALLOC(strm, s->hash_size, sizeof(Pos)); |
| 620 | |
| 621 | s->lit_bufsize = 1 << (memLevel + 6); /* 16K elements by default */ |
| 622 | |
| 623 | s->pending_buf = (uchf *) ZALLOC(strm, s->lit_bufsize, 2*sizeof(ush)); |
| 624 | |
| 625 | if (s->window == Z_NULL || s->prev == Z_NULL || s->head == Z_NULL || |
| 626 | s->pending_buf == Z_NULL) { |
| 627 | strm->msg = z_errmsg[1-Z_MEM_ERROR]; |
| 628 | deflateEnd (strm); |
| 629 | return Z_MEM_ERROR; |
| 630 | } |
| 631 | s->d_buf = (ushf *) &(s->pending_buf[s->lit_bufsize]); |
| 632 | s->l_buf = (uchf *) &(s->pending_buf[3*s->lit_bufsize]); |
| 633 | /* We overlay pending_buf and d_buf+l_buf. This works since the average |
| 634 | * output size for (length,distance) codes is <= 32 bits (worst case |
| 635 | * is 15+15+13=33). |
| 636 | */ |
| 637 | |
| 638 | s->level = level; |
| 639 | s->strategy = strategy; |
| 640 | s->method = (Byte)method; |
| 641 | s->blocks_in_packet = 0; |
| 642 | |
| 643 | return deflateReset(strm); |
| 644 | } |
| 645 | |
| 646 | /* ========================================================================= */ |
| 647 | int deflateReset (strm) |
| 648 | z_stream *strm; |
| 649 | { |
| 650 | deflate_state *s; |
| 651 | |
| 652 | if (strm == Z_NULL || strm->state == Z_NULL || |
| 653 | strm->zalloc == Z_NULL || strm->zfree == Z_NULL) return Z_STREAM_ERROR; |
| 654 | |
| 655 | strm->total_in = strm->total_out = 0; |
| 656 | strm->msg = Z_NULL; /* use zfree if we ever allocate msg dynamically */ |
| 657 | strm->data_type = Z_UNKNOWN; |
| 658 | |
| 659 | s = (deflate_state *)strm->state; |
| 660 | s->pending = 0; |
| 661 | s->pending_out = s->pending_buf; |
| 662 | |
| 663 | if (s->noheader < 0) { |
| 664 | s->noheader = 0; /* was set to -1 by deflate(..., Z_FINISH); */ |
| 665 | } |
| 666 | s->status = s->noheader ? BUSY_STATE : INIT_STATE; |
| 667 | s->adler = 1; |
| 668 | |
| 669 | ct_init(s); |
| 670 | lm_init(s); |
| 671 | |
| 672 | return Z_OK; |
| 673 | } |
| 674 | |
| 675 | /* ========================================================================= |
| 676 | * Put a short in the pending buffer. The 16-bit value is put in MSB order. |
| 677 | * IN assertion: the stream state is correct and there is enough room in |
| 678 | * pending_buf. |
| 679 | */ |
| 680 | local void putShortMSB (s, b) |
| 681 | deflate_state *s; |
| 682 | uInt b; |
| 683 | { |
| 684 | put_byte(s, (Byte)(b >> 8)); |
| 685 | put_byte(s, (Byte)(b & 0xff)); |
| 686 | } |
| 687 | |
| 688 | /* ========================================================================= |
| 689 | * Flush as much pending output as possible. |
| 690 | */ |
| 691 | local void flush_pending(strm) |
| 692 | z_stream *strm; |
| 693 | { |
| 694 | deflate_state *state = (deflate_state *) strm->state; |
| 695 | unsigned len = state->pending; |
| 696 | |
| 697 | if (len > strm->avail_out) len = strm->avail_out; |
| 698 | if (len == 0) return; |
| 699 | |
| 700 | if (strm->next_out != NULL) { |
| 701 | zmemcpy(strm->next_out, state->pending_out, len); |
| 702 | strm->next_out += len; |
| 703 | } |
| 704 | state->pending_out += len; |
| 705 | strm->total_out += len; |
| 706 | strm->avail_out -= len; |
| 707 | state->pending -= len; |
| 708 | if (state->pending == 0) { |
| 709 | state->pending_out = state->pending_buf; |
| 710 | } |
| 711 | } |
| 712 | |
| 713 | /* ========================================================================= */ |
| 714 | int deflate (strm, flush) |
| 715 | z_stream *strm; |
| 716 | int flush; |
| 717 | { |
| 718 | deflate_state *state = (deflate_state *) strm->state; |
| 719 | |
| 720 | if (strm == Z_NULL || state == Z_NULL) return Z_STREAM_ERROR; |
| 721 | |
| 722 | if (strm->next_in == Z_NULL && strm->avail_in != 0) { |
| 723 | ERR_RETURN(strm, Z_STREAM_ERROR); |
| 724 | } |
| 725 | if (strm->avail_out == 0) ERR_RETURN(strm, Z_BUF_ERROR); |
| 726 | |
| 727 | state->strm = strm; /* just in case */ |
| 728 | |
| 729 | /* Write the zlib header */ |
| 730 | if (state->status == INIT_STATE) { |
| 731 | |
| 732 | uInt header = (DEFLATED + ((state->w_bits-8)<<4)) << 8; |
| 733 | uInt level_flags = (state->level-1) >> 1; |
| 734 | |
| 735 | if (level_flags > 3) level_flags = 3; |
| 736 | header |= (level_flags << 6); |
| 737 | header += 31 - (header % 31); |
| 738 | |
| 739 | state->status = BUSY_STATE; |
| 740 | putShortMSB(state, header); |
| 741 | } |
| 742 | |
| 743 | /* Flush as much pending output as possible */ |
| 744 | if (state->pending != 0) { |
| 745 | flush_pending(strm); |
| 746 | if (strm->avail_out == 0) return Z_OK; |
| 747 | } |
| 748 | |
| 749 | /* If we came back in here to get the last output from |
| 750 | * a previous flush, we're done for now. |
| 751 | */ |
| 752 | if (state->status == FLUSH_STATE) { |
| 753 | state->status = BUSY_STATE; |
| 754 | if (flush != Z_NO_FLUSH && flush != Z_FINISH) |
| 755 | return Z_OK; |
| 756 | } |
| 757 | |
| 758 | /* User must not provide more input after the first FINISH: */ |
| 759 | if (state->status == FINISH_STATE && strm->avail_in != 0) { |
| 760 | ERR_RETURN(strm, Z_BUF_ERROR); |
| 761 | } |
| 762 | |
| 763 | /* Start a new block or continue the current one. |
| 764 | */ |
| 765 | if (strm->avail_in != 0 || state->lookahead != 0 || |
| 766 | (flush == Z_FINISH && state->status != FINISH_STATE)) { |
| 767 | int quit; |
| 768 | |
| 769 | if (flush == Z_FINISH) { |
| 770 | state->status = FINISH_STATE; |
| 771 | } |
| 772 | if (state->level <= 3) { |
| 773 | quit = deflate_fast(state, flush); |
| 774 | } else { |
| 775 | quit = deflate_slow(state, flush); |
| 776 | } |
| 777 | if (quit || strm->avail_out == 0) |
| 778 | return Z_OK; |
| 779 | /* If flush != Z_NO_FLUSH && avail_out == 0, the next call |
| 780 | * of deflate should use the same flush parameter to make sure |
| 781 | * that the flush is complete. So we don't have to output an |
| 782 | * empty block here, this will be done at next call. This also |
| 783 | * ensures that for a very small output buffer, we emit at most |
| 784 | * one empty block. |
| 785 | */ |
| 786 | } |
| 787 | |
| 788 | /* If a flush was requested, we have a little more to output now. */ |
| 789 | if (flush != Z_NO_FLUSH && flush != Z_FINISH |
| 790 | && state->status != FINISH_STATE) { |
| 791 | switch (flush) { |
| 792 | case Z_PARTIAL_FLUSH: |
| 793 | ct_align(state); |
| 794 | break; |
| 795 | case Z_PACKET_FLUSH: |
| 796 | /* Output just the 3-bit `stored' block type value, |
| 797 | but not a zero length. */ |
| 798 | ct_stored_type_only(state); |
| 799 | break; |
| 800 | default: |
| 801 | ct_stored_block(state, (char*)0, 0L, 0); |
| 802 | /* For a full flush, this empty block will be recognized |
| 803 | * as a special marker by inflate_sync(). |
| 804 | */ |
| 805 | if (flush == Z_FULL_FLUSH) { |
| 806 | CLEAR_HASH(state); /* forget history */ |
| 807 | } |
| 808 | } |
| 809 | flush_pending(strm); |
| 810 | if (strm->avail_out == 0) { |
| 811 | /* We'll have to come back to get the rest of the output; |
| 812 | * this ensures we don't output a second zero-length stored |
| 813 | * block (or whatever). |
| 814 | */ |
| 815 | state->status = FLUSH_STATE; |
| 816 | return Z_OK; |
| 817 | } |
| 818 | } |
| 819 | |
| 820 | Assert(strm->avail_out > 0, "bug2"); |
| 821 | |
| 822 | if (flush != Z_FINISH) return Z_OK; |
| 823 | if (state->noheader) return Z_STREAM_END; |
| 824 | |
| 825 | /* Write the zlib trailer (adler32) */ |
| 826 | putShortMSB(state, (uInt)(state->adler >> 16)); |
| 827 | putShortMSB(state, (uInt)(state->adler & 0xffff)); |
| 828 | flush_pending(strm); |
| 829 | /* If avail_out is zero, the application will call deflate again |
| 830 | * to flush the rest. |
| 831 | */ |
| 832 | state->noheader = -1; /* write the trailer only once! */ |
| 833 | return state->pending != 0 ? Z_OK : Z_STREAM_END; |
| 834 | } |
| 835 | |
| 836 | /* ========================================================================= */ |
| 837 | int deflateEnd (strm) |
| 838 | z_stream *strm; |
| 839 | { |
| 840 | deflate_state *state = (deflate_state *) strm->state; |
| 841 | |
| 842 | if (strm == Z_NULL || state == Z_NULL) return Z_STREAM_ERROR; |
| 843 | |
| 844 | TRY_FREE(strm, state->window, state->w_size * 2 * sizeof(Byte)); |
| 845 | TRY_FREE(strm, state->prev, state->w_size * sizeof(Pos)); |
| 846 | TRY_FREE(strm, state->head, state->hash_size * sizeof(Pos)); |
| 847 | TRY_FREE(strm, state->pending_buf, state->lit_bufsize * 2 * sizeof(ush)); |
| 848 | |
| 849 | ZFREE(strm, state, sizeof(deflate_state)); |
| 850 | strm->state = Z_NULL; |
| 851 | |
| 852 | return Z_OK; |
| 853 | } |
| 854 | |
| 855 | /* =========================================================================== |
| 856 | * Read a new buffer from the current input stream, update the adler32 |
| 857 | * and total number of bytes read. |
| 858 | */ |
| 859 | local int zread_buf(strm, buf, size) |
| 860 | z_stream *strm; |
| 861 | charf *buf; |
| 862 | unsigned size; |
| 863 | { |
| 864 | unsigned len = strm->avail_in; |
| 865 | deflate_state *state = (deflate_state *) strm->state; |
| 866 | |
| 867 | if (len > size) len = size; |
| 868 | if (len == 0) return 0; |
| 869 | |
| 870 | strm->avail_in -= len; |
| 871 | |
| 872 | if (!state->noheader) { |
| 873 | state->adler = adler32(state->adler, strm->next_in, len); |
| 874 | } |
| 875 | zmemcpy(buf, strm->next_in, len); |
| 876 | strm->next_in += len; |
| 877 | strm->total_in += len; |
| 878 | |
| 879 | return (int)len; |
| 880 | } |
| 881 | |
| 882 | /* =========================================================================== |
| 883 | * Initialize the "longest match" routines for a new zlib stream |
| 884 | */ |
| 885 | local void lm_init (s) |
| 886 | deflate_state *s; |
| 887 | { |
| 888 | s->window_size = (ulg)2L*s->w_size; |
| 889 | |
| 890 | CLEAR_HASH(s); |
| 891 | |
| 892 | /* Set the default configuration parameters: |
| 893 | */ |
| 894 | s->max_lazy_match = configuration_table[s->level].max_lazy; |
| 895 | s->good_match = configuration_table[s->level].good_length; |
| 896 | s->nice_match = configuration_table[s->level].nice_length; |
| 897 | s->max_chain_length = configuration_table[s->level].max_chain; |
| 898 | |
| 899 | s->strstart = 0; |
| 900 | s->block_start = 0L; |
| 901 | s->lookahead = 0; |
| 902 | s->match_length = MIN_MATCH-1; |
| 903 | s->match_available = 0; |
| 904 | s->ins_h = 0; |
| 905 | #ifdef ASMV |
| 906 | match_init(); /* initialize the asm code */ |
| 907 | #endif |
| 908 | } |
| 909 | |
| 910 | /* =========================================================================== |
| 911 | * Set match_start to the longest match starting at the given string and |
| 912 | * return its length. Matches shorter or equal to prev_length are discarded, |
| 913 | * in which case the result is equal to prev_length and match_start is |
| 914 | * garbage. |
| 915 | * IN assertions: cur_match is the head of the hash chain for the current |
| 916 | * string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1 |
| 917 | */ |
| 918 | #ifndef ASMV |
| 919 | /* For 80x86 and 680x0, an optimized version will be provided in match.asm or |
| 920 | * match.S. The code will be functionally equivalent. |
| 921 | */ |
| 922 | local int longest_match(s, cur_match) |
| 923 | deflate_state *s; |
| 924 | IPos cur_match; /* current match */ |
| 925 | { |
| 926 | unsigned chain_length = s->max_chain_length;/* max hash chain length */ |
| 927 | register Bytef *scan = s->window + s->strstart; /* current string */ |
| 928 | register Bytef *match; /* matched string */ |
| 929 | register int len; /* length of current match */ |
| 930 | int best_len = s->prev_length; /* best match length so far */ |
| 931 | IPos limit = s->strstart > (IPos)MAX_DIST(s) ? |
| 932 | s->strstart - (IPos)MAX_DIST(s) : NIL; |
| 933 | /* Stop when cur_match becomes <= limit. To simplify the code, |
| 934 | * we prevent matches with the string of window index 0. |
| 935 | */ |
| 936 | Posf *prev = s->prev; |
| 937 | uInt wmask = s->w_mask; |
| 938 | |
| 939 | #ifdef UNALIGNED_OK |
| 940 | /* Compare two bytes at a time. Note: this is not always beneficial. |
| 941 | * Try with and without -DUNALIGNED_OK to check. |
| 942 | */ |
| 943 | register Bytef *strend = s->window + s->strstart + MAX_MATCH - 1; |
| 944 | register ush scan_start = *(ushf*)scan; |
| 945 | register ush scan_end = *(ushf*)(scan+best_len-1); |
| 946 | #else |
| 947 | register Bytef *strend = s->window + s->strstart + MAX_MATCH; |
| 948 | register Byte scan_end1 = scan[best_len-1]; |
| 949 | register Byte scan_end = scan[best_len]; |
| 950 | #endif |
| 951 | |
| 952 | /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16. |
| 953 | * It is easy to get rid of this optimization if necessary. |
| 954 | */ |
| 955 | Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever"); |
| 956 | |
| 957 | /* Do not waste too much time if we already have a good match: */ |
| 958 | if (s->prev_length >= s->good_match) { |
| 959 | chain_length >>= 2; |
| 960 | } |
| 961 | Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead"); |
| 962 | |
| 963 | do { |
| 964 | Assert(cur_match < s->strstart, "no future"); |
| 965 | match = s->window + cur_match; |
| 966 | |
| 967 | /* Skip to next match if the match length cannot increase |
| 968 | * or if the match length is less than 2: |
| 969 | */ |
| 970 | #if (defined(UNALIGNED_OK) && MAX_MATCH == 258) |
| 971 | /* This code assumes sizeof(unsigned short) == 2. Do not use |
| 972 | * UNALIGNED_OK if your compiler uses a different size. |
| 973 | */ |
| 974 | if (*(ushf*)(match+best_len-1) != scan_end || |
| 975 | *(ushf*)match != scan_start) continue; |
| 976 | |
| 977 | /* It is not necessary to compare scan[2] and match[2] since they are |
| 978 | * always equal when the other bytes match, given that the hash keys |
| 979 | * are equal and that HASH_BITS >= 8. Compare 2 bytes at a time at |
| 980 | * strstart+3, +5, ... up to strstart+257. We check for insufficient |
| 981 | * lookahead only every 4th comparison; the 128th check will be made |
| 982 | * at strstart+257. If MAX_MATCH-2 is not a multiple of 8, it is |
| 983 | * necessary to put more guard bytes at the end of the window, or |
| 984 | * to check more often for insufficient lookahead. |
| 985 | */ |
| 986 | Assert(scan[2] == match[2], "scan[2]?"); |
| 987 | scan++, match++; |
| 988 | do { |
| 989 | } while (*(ushf*)(scan+=2) == *(ushf*)(match+=2) && |
| 990 | *(ushf*)(scan+=2) == *(ushf*)(match+=2) && |
| 991 | *(ushf*)(scan+=2) == *(ushf*)(match+=2) && |
| 992 | *(ushf*)(scan+=2) == *(ushf*)(match+=2) && |
| 993 | scan < strend); |
| 994 | /* The funny "do {}" generates better code on most compilers */ |
| 995 | |
| 996 | /* Here, scan <= window+strstart+257 */ |
| 997 | Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan"); |
| 998 | if (*scan == *match) scan++; |
| 999 | |
| 1000 | len = (MAX_MATCH - 1) - (int)(strend-scan); |
| 1001 | scan = strend - (MAX_MATCH-1); |
| 1002 | |
| 1003 | #else /* UNALIGNED_OK */ |
| 1004 | |
| 1005 | if (match[best_len] != scan_end || |
| 1006 | match[best_len-1] != scan_end1 || |
| 1007 | *match != *scan || |
| 1008 | *++match != scan[1]) continue; |
| 1009 | |
| 1010 | /* The check at best_len-1 can be removed because it will be made |
| 1011 | * again later. (This heuristic is not always a win.) |
| 1012 | * It is not necessary to compare scan[2] and match[2] since they |
| 1013 | * are always equal when the other bytes match, given that |
| 1014 | * the hash keys are equal and that HASH_BITS >= 8. |
| 1015 | */ |
| 1016 | scan += 2, match++; |
| 1017 | Assert(*scan == *match, "match[2]?"); |
| 1018 | |
| 1019 | /* We check for insufficient lookahead only every 8th comparison; |
| 1020 | * the 256th check will be made at strstart+258. |
| 1021 | */ |
| 1022 | do { |
| 1023 | } while (*++scan == *++match && *++scan == *++match && |
| 1024 | *++scan == *++match && *++scan == *++match && |
| 1025 | *++scan == *++match && *++scan == *++match && |
| 1026 | *++scan == *++match && *++scan == *++match && |
| 1027 | scan < strend); |
| 1028 | |
| 1029 | Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan"); |
| 1030 | |
| 1031 | len = MAX_MATCH - (int)(strend - scan); |
| 1032 | scan = strend - MAX_MATCH; |
| 1033 | |
| 1034 | #endif /* UNALIGNED_OK */ |
| 1035 | |
| 1036 | if (len > best_len) { |
| 1037 | s->match_start = cur_match; |
| 1038 | best_len = len; |
| 1039 | if (len >= s->nice_match) break; |
| 1040 | #ifdef UNALIGNED_OK |
| 1041 | scan_end = *(ushf*)(scan+best_len-1); |
| 1042 | #else |
| 1043 | scan_end1 = scan[best_len-1]; |
| 1044 | scan_end = scan[best_len]; |
| 1045 | #endif |
| 1046 | } |
| 1047 | } while ((cur_match = prev[cur_match & wmask]) > limit |
| 1048 | && --chain_length != 0); |
| 1049 | |
| 1050 | return best_len; |
| 1051 | } |
| 1052 | #endif /* ASMV */ |
| 1053 | |
| 1054 | #ifdef DEBUG_ZLIB |
| 1055 | /* =========================================================================== |
| 1056 | * Check that the match at match_start is indeed a match. |
| 1057 | */ |
| 1058 | local void check_match(s, start, match, length) |
| 1059 | deflate_state *s; |
| 1060 | IPos start, match; |
| 1061 | int length; |
| 1062 | { |
| 1063 | /* check that the match is indeed a match */ |
| 1064 | if (memcmp((charf *)s->window + match, |
| 1065 | (charf *)s->window + start, length) != EQUAL) { |
| 1066 | fprintf(stderr, |
| 1067 | " start %u, match %u, length %d\n", |
| 1068 | start, match, length); |
| 1069 | do { fprintf(stderr, "%c%c", s->window[match++], |
| 1070 | s->window[start++]); } while (--length != 0); |
| 1071 | z_error("invalid match"); |
| 1072 | } |
| 1073 | if (verbose > 1) { |
| 1074 | fprintf(stderr,"\\[%d,%d]", start-match, length); |
| 1075 | do { putc(s->window[start++], stderr); } while (--length != 0); |
| 1076 | } |
| 1077 | } |
| 1078 | #else |
| 1079 | # define check_match(s, start, match, length) |
| 1080 | #endif |
| 1081 | |
| 1082 | /* =========================================================================== |
| 1083 | * Fill the window when the lookahead becomes insufficient. |
| 1084 | * Updates strstart and lookahead. |
| 1085 | * |
| 1086 | * IN assertion: lookahead < MIN_LOOKAHEAD |
| 1087 | * OUT assertions: strstart <= window_size-MIN_LOOKAHEAD |
| 1088 | * At least one byte has been read, or avail_in == 0; reads are |
| 1089 | * performed for at least two bytes (required for the zip translate_eol |
| 1090 | * option -- not supported here). |
| 1091 | */ |
| 1092 | local void fill_window(s) |
| 1093 | deflate_state *s; |
| 1094 | { |
| 1095 | register unsigned n, m; |
| 1096 | register Posf *p; |
| 1097 | unsigned more; /* Amount of free space at the end of the window. */ |
| 1098 | uInt wsize = s->w_size; |
| 1099 | |
| 1100 | do { |
| 1101 | more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart); |
| 1102 | |
| 1103 | /* Deal with !@#$% 64K limit: */ |
| 1104 | if (more == 0 && s->strstart == 0 && s->lookahead == 0) { |
| 1105 | more = wsize; |
| 1106 | } else if (more == (unsigned)(-1)) { |
| 1107 | /* Very unlikely, but possible on 16 bit machine if strstart == 0 |
| 1108 | * and lookahead == 1 (input done one byte at time) |
| 1109 | */ |
| 1110 | more--; |
| 1111 | |
| 1112 | /* If the window is almost full and there is insufficient lookahead, |
| 1113 | * move the upper half to the lower one to make room in the upper half. |
| 1114 | */ |
| 1115 | } else if (s->strstart >= wsize+MAX_DIST(s)) { |
| 1116 | |
| 1117 | /* By the IN assertion, the window is not empty so we can't confuse |
| 1118 | * more == 0 with more == 64K on a 16 bit machine. |
| 1119 | */ |
| 1120 | zmemcpy((charf *)s->window, (charf *)s->window+wsize, |
| 1121 | (unsigned)wsize); |
| 1122 | s->match_start -= wsize; |
| 1123 | s->strstart -= wsize; /* we now have strstart >= MAX_DIST */ |
| 1124 | |
| 1125 | s->block_start -= (Long) wsize; |
| 1126 | |
| 1127 | /* Slide the hash table (could be avoided with 32 bit values |
| 1128 | at the expense of memory usage): |
| 1129 | */ |
| 1130 | n = s->hash_size; |
| 1131 | p = &s->head[n]; |
| 1132 | do { |
| 1133 | m = *--p; |
| 1134 | *p = (Pos)(m >= wsize ? m-wsize : NIL); |
| 1135 | } while (--n); |
| 1136 | |
| 1137 | n = wsize; |
| 1138 | p = &s->prev[n]; |
| 1139 | do { |
| 1140 | m = *--p; |
| 1141 | *p = (Pos)(m >= wsize ? m-wsize : NIL); |
| 1142 | /* If n is not on any hash chain, prev[n] is garbage but |
| 1143 | * its value will never be used. |
| 1144 | */ |
| 1145 | } while (--n); |
| 1146 | |
| 1147 | more += wsize; |
| 1148 | } |
| 1149 | if (s->strm->avail_in == 0) return; |
| 1150 | |
| 1151 | /* If there was no sliding: |
| 1152 | * strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 && |
| 1153 | * more == window_size - lookahead - strstart |
| 1154 | * => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1) |
| 1155 | * => more >= window_size - 2*WSIZE + 2 |
| 1156 | * In the BIG_MEM or MMAP case (not yet supported), |
| 1157 | * window_size == input_size + MIN_LOOKAHEAD && |
| 1158 | * strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD. |
| 1159 | * Otherwise, window_size == 2*WSIZE so more >= 2. |
| 1160 | * If there was sliding, more >= WSIZE. So in all cases, more >= 2. |
| 1161 | */ |
| 1162 | Assert(more >= 2, "more < 2"); |
| 1163 | |
| 1164 | n = zread_buf(s->strm, (charf *)s->window + s->strstart + s->lookahead, |
| 1165 | more); |
| 1166 | s->lookahead += n; |
| 1167 | |
| 1168 | /* Initialize the hash value now that we have some input: */ |
| 1169 | if (s->lookahead >= MIN_MATCH) { |
| 1170 | s->ins_h = s->window[s->strstart]; |
| 1171 | UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]); |
| 1172 | #if MIN_MATCH != 3 |
| 1173 | Call UPDATE_HASH() MIN_MATCH-3 more times |
| 1174 | #endif |
| 1175 | } |
| 1176 | /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage, |
| 1177 | * but this is not important since only literal bytes will be emitted. |
| 1178 | */ |
| 1179 | |
| 1180 | } while (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0); |
| 1181 | } |
| 1182 | |
| 1183 | /* =========================================================================== |
| 1184 | * Flush the current block, with given end-of-file flag. |
| 1185 | * IN assertion: strstart is set to the end of the current match. |
| 1186 | */ |
| 1187 | #define FLUSH_BLOCK_ONLY(s, flush) { \ |
| 1188 | ct_flush_block(s, (s->block_start >= 0L ? \ |
| 1189 | (charf *)&s->window[(unsigned)s->block_start] : \ |
| 1190 | (charf *)Z_NULL), (Long)s->strstart - s->block_start, (flush)); \ |
| 1191 | s->block_start = s->strstart; \ |
| 1192 | flush_pending(s->strm); \ |
| 1193 | Tracev((stderr,"[FLUSH]")); \ |
| 1194 | } |
| 1195 | |
| 1196 | /* Same but force premature exit if necessary. */ |
| 1197 | #define FLUSH_BLOCK(s, flush) { \ |
| 1198 | FLUSH_BLOCK_ONLY(s, flush); \ |
| 1199 | if (s->strm->avail_out == 0) return 1; \ |
| 1200 | } |
| 1201 | |
| 1202 | /* =========================================================================== |
| 1203 | * Compress as much as possible from the input stream, return true if |
| 1204 | * processing was terminated prematurely (no more input or output space). |
| 1205 | * This function does not perform lazy evaluationof matches and inserts |
| 1206 | * new strings in the dictionary only for unmatched strings or for short |
| 1207 | * matches. It is used only for the fast compression options. |
| 1208 | */ |
| 1209 | local int deflate_fast(s, flush) |
| 1210 | deflate_state *s; |
| 1211 | int flush; |
| 1212 | { |
| 1213 | IPos hash_head = NIL; /* head of the hash chain */ |
| 1214 | int bflush; /* set if current block must be flushed */ |
| 1215 | |
| 1216 | s->prev_length = MIN_MATCH-1; |
| 1217 | |
| 1218 | for (;;) { |
| 1219 | /* Make sure that we always have enough lookahead, except |
| 1220 | * at the end of the input file. We need MAX_MATCH bytes |
| 1221 | * for the next match, plus MIN_MATCH bytes to insert the |
| 1222 | * string following the next match. |
| 1223 | */ |
| 1224 | if (s->lookahead < MIN_LOOKAHEAD) { |
| 1225 | fill_window(s); |
| 1226 | if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) return 1; |
| 1227 | |
| 1228 | if (s->lookahead == 0) break; /* flush the current block */ |
| 1229 | } |
| 1230 | |
| 1231 | /* Insert the string window[strstart .. strstart+2] in the |
| 1232 | * dictionary, and set hash_head to the head of the hash chain: |
| 1233 | */ |
| 1234 | if (s->lookahead >= MIN_MATCH) { |
| 1235 | INSERT_STRING(s, s->strstart, hash_head); |
| 1236 | } |
| 1237 | |
| 1238 | /* Find the longest match, discarding those <= prev_length. |
| 1239 | * At this point we have always match_length < MIN_MATCH |
| 1240 | */ |
| 1241 | if (hash_head != NIL && s->strstart - hash_head <= MAX_DIST(s)) { |
| 1242 | /* To simplify the code, we prevent matches with the string |
| 1243 | * of window index 0 (in particular we have to avoid a match |
| 1244 | * of the string with itself at the start of the input file). |
| 1245 | */ |
| 1246 | if (s->strategy != Z_HUFFMAN_ONLY) { |
| 1247 | s->match_length = longest_match (s, hash_head); |
| 1248 | } |
| 1249 | /* longest_match() sets match_start */ |
| 1250 | |
| 1251 | if (s->match_length > s->lookahead) s->match_length = s->lookahead; |
| 1252 | } |
| 1253 | if (s->match_length >= MIN_MATCH) { |
| 1254 | check_match(s, s->strstart, s->match_start, s->match_length); |
| 1255 | |
| 1256 | bflush = ct_tally(s, s->strstart - s->match_start, |
| 1257 | s->match_length - MIN_MATCH); |
| 1258 | |
| 1259 | s->lookahead -= s->match_length; |
| 1260 | |
| 1261 | /* Insert new strings in the hash table only if the match length |
| 1262 | * is not too large. This saves time but degrades compression. |
| 1263 | */ |
| 1264 | if (s->match_length <= s->max_insert_length && |
| 1265 | s->lookahead >= MIN_MATCH) { |
| 1266 | s->match_length--; /* string at strstart already in hash table */ |
| 1267 | do { |
| 1268 | s->strstart++; |
| 1269 | INSERT_STRING(s, s->strstart, hash_head); |
| 1270 | /* strstart never exceeds WSIZE-MAX_MATCH, so there are |
| 1271 | * always MIN_MATCH bytes ahead. |
| 1272 | */ |
| 1273 | } while (--s->match_length != 0); |
| 1274 | s->strstart++; |
| 1275 | } else { |
| 1276 | s->strstart += s->match_length; |
| 1277 | s->match_length = 0; |
| 1278 | s->ins_h = s->window[s->strstart]; |
| 1279 | UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]); |
| 1280 | #if MIN_MATCH != 3 |
| 1281 | Call UPDATE_HASH() MIN_MATCH-3 more times |
| 1282 | #endif |
| 1283 | /* If lookahead < MIN_MATCH, ins_h is garbage, but it does not |
| 1284 | * matter since it will be recomputed at next deflate call. |
| 1285 | */ |
| 1286 | } |
| 1287 | } else { |
| 1288 | /* No match, output a literal byte */ |
| 1289 | Tracevv((stderr,"%c", s->window[s->strstart])); |
| 1290 | bflush = ct_tally (s, 0, s->window[s->strstart]); |
| 1291 | s->lookahead--; |
| 1292 | s->strstart++; |
| 1293 | } |
| 1294 | if (bflush) FLUSH_BLOCK(s, Z_NO_FLUSH); |
| 1295 | } |
| 1296 | FLUSH_BLOCK(s, flush); |
| 1297 | return 0; /* normal exit */ |
| 1298 | } |
| 1299 | |
| 1300 | /* =========================================================================== |
| 1301 | * Same as above, but achieves better compression. We use a lazy |
| 1302 | * evaluation for matches: a match is finally adopted only if there is |
| 1303 | * no better match at the next window position. |
| 1304 | */ |
| 1305 | local int deflate_slow(s, flush) |
| 1306 | deflate_state *s; |
| 1307 | int flush; |
| 1308 | { |
| 1309 | IPos hash_head = NIL; /* head of hash chain */ |
| 1310 | int bflush; /* set if current block must be flushed */ |
| 1311 | |
| 1312 | /* Process the input block. */ |
| 1313 | for (;;) { |
| 1314 | /* Make sure that we always have enough lookahead, except |
| 1315 | * at the end of the input file. We need MAX_MATCH bytes |
| 1316 | * for the next match, plus MIN_MATCH bytes to insert the |
| 1317 | * string following the next match. |
| 1318 | */ |
| 1319 | if (s->lookahead < MIN_LOOKAHEAD) { |
| 1320 | fill_window(s); |
| 1321 | if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) return 1; |
| 1322 | |
| 1323 | if (s->lookahead == 0) break; /* flush the current block */ |
| 1324 | } |
| 1325 | |
| 1326 | /* Insert the string window[strstart .. strstart+2] in the |
| 1327 | * dictionary, and set hash_head to the head of the hash chain: |
| 1328 | */ |
| 1329 | if (s->lookahead >= MIN_MATCH) { |
| 1330 | INSERT_STRING(s, s->strstart, hash_head); |
| 1331 | } |
| 1332 | |
| 1333 | if (flush == Z_INSERT_ONLY) { |
| 1334 | s->strstart++; |
| 1335 | s->lookahead--; |
| 1336 | continue; |
| 1337 | } |
| 1338 | |
| 1339 | /* Find the longest match, discarding those <= prev_length. |
| 1340 | */ |
| 1341 | s->prev_length = s->match_length, s->prev_match = s->match_start; |
| 1342 | s->match_length = MIN_MATCH-1; |
| 1343 | |
| 1344 | if (hash_head != NIL && s->prev_length < s->max_lazy_match && |
| 1345 | s->strstart - hash_head <= MAX_DIST(s)) { |
| 1346 | /* To simplify the code, we prevent matches with the string |
| 1347 | * of window index 0 (in particular we have to avoid a match |
| 1348 | * of the string with itself at the start of the input file). |
| 1349 | */ |
| 1350 | if (s->strategy != Z_HUFFMAN_ONLY) { |
| 1351 | s->match_length = longest_match (s, hash_head); |
| 1352 | } |
| 1353 | /* longest_match() sets match_start */ |
| 1354 | if (s->match_length > s->lookahead) s->match_length = s->lookahead; |
| 1355 | |
| 1356 | if (s->match_length <= 5 && (s->strategy == Z_FILTERED || |
| 1357 | (s->match_length == MIN_MATCH && |
| 1358 | s->strstart - s->match_start > TOO_FAR))) { |
| 1359 | |
| 1360 | /* If prev_match is also MIN_MATCH, match_start is garbage |
| 1361 | * but we will ignore the current match anyway. |
| 1362 | */ |
| 1363 | s->match_length = MIN_MATCH-1; |
| 1364 | } |
| 1365 | } |
| 1366 | /* If there was a match at the previous step and the current |
| 1367 | * match is not better, output the previous match: |
| 1368 | */ |
| 1369 | if (s->prev_length >= MIN_MATCH && s->match_length <= s->prev_length) { |
| 1370 | uInt max_insert = s->strstart + s->lookahead - MIN_MATCH; |
| 1371 | /* Do not insert strings in hash table beyond this. */ |
| 1372 | |
| 1373 | check_match(s, s->strstart-1, s->prev_match, s->prev_length); |
| 1374 | |
| 1375 | bflush = ct_tally(s, s->strstart -1 - s->prev_match, |
| 1376 | s->prev_length - MIN_MATCH); |
| 1377 | |
| 1378 | /* Insert in hash table all strings up to the end of the match. |
| 1379 | * strstart-1 and strstart are already inserted. If there is not |
| 1380 | * enough lookahead, the last two strings are not inserted in |
| 1381 | * the hash table. |
| 1382 | */ |
| 1383 | s->lookahead -= s->prev_length-1; |
| 1384 | s->prev_length -= 2; |
| 1385 | do { |
| 1386 | if (++s->strstart <= max_insert) { |
| 1387 | INSERT_STRING(s, s->strstart, hash_head); |
| 1388 | } |
| 1389 | } while (--s->prev_length != 0); |
| 1390 | s->match_available = 0; |
| 1391 | s->match_length = MIN_MATCH-1; |
| 1392 | s->strstart++; |
| 1393 | |
| 1394 | if (bflush) FLUSH_BLOCK(s, Z_NO_FLUSH); |
| 1395 | |
| 1396 | } else if (s->match_available) { |
| 1397 | /* If there was no match at the previous position, output a |
| 1398 | * single literal. If there was a match but the current match |
| 1399 | * is longer, truncate the previous match to a single literal. |
| 1400 | */ |
| 1401 | Tracevv((stderr,"%c", s->window[s->strstart-1])); |
| 1402 | if (ct_tally (s, 0, s->window[s->strstart-1])) { |
| 1403 | FLUSH_BLOCK_ONLY(s, Z_NO_FLUSH); |
| 1404 | } |
| 1405 | s->strstart++; |
| 1406 | s->lookahead--; |
| 1407 | if (s->strm->avail_out == 0) return 1; |
| 1408 | } else { |
| 1409 | /* There is no previous match to compare with, wait for |
| 1410 | * the next step to decide. |
| 1411 | */ |
| 1412 | s->match_available = 1; |
| 1413 | s->strstart++; |
| 1414 | s->lookahead--; |
| 1415 | } |
| 1416 | } |
| 1417 | if (flush == Z_INSERT_ONLY) { |
| 1418 | s->block_start = s->strstart; |
| 1419 | return 1; |
| 1420 | } |
| 1421 | Assert (flush != Z_NO_FLUSH, "no flush?"); |
| 1422 | if (s->match_available) { |
| 1423 | Tracevv((stderr,"%c", s->window[s->strstart-1])); |
| 1424 | ct_tally (s, 0, s->window[s->strstart-1]); |
| 1425 | s->match_available = 0; |
| 1426 | } |
| 1427 | FLUSH_BLOCK(s, flush); |
| 1428 | return 0; |
| 1429 | } |
| 1430 | |
| 1431 | |
| 1432 | /*+++++*/ |
| 1433 | /* trees.c -- output deflated data using Huffman coding |
| 1434 | * Copyright (C) 1995 Jean-loup Gailly |
| 1435 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 1436 | */ |
| 1437 | |
| 1438 | /* |
| 1439 | * ALGORITHM |
| 1440 | * |
| 1441 | * The "deflation" process uses several Huffman trees. The more |
| 1442 | * common source values are represented by shorter bit sequences. |
| 1443 | * |
| 1444 | * Each code tree is stored in a compressed form which is itself |
| 1445 | * a Huffman encoding of the lengths of all the code strings (in |
| 1446 | * ascending order by source values). The actual code strings are |
| 1447 | * reconstructed from the lengths in the inflate process, as described |
| 1448 | * in the deflate specification. |
| 1449 | * |
| 1450 | * REFERENCES |
| 1451 | * |
| 1452 | * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification". |
| 1453 | * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc |
| 1454 | * |
| 1455 | * Storer, James A. |
| 1456 | * Data Compression: Methods and Theory, pp. 49-50. |
| 1457 | * Computer Science Press, 1988. ISBN 0-7167-8156-5. |
| 1458 | * |
| 1459 | * Sedgewick, R. |
| 1460 | * Algorithms, p290. |
| 1461 | * Addison-Wesley, 1983. ISBN 0-201-06672-6. |
| 1462 | */ |
| 1463 | |
| 1464 | /* From: trees.c,v 1.5 1995/05/03 17:27:12 jloup Exp */ |
| 1465 | |
| 1466 | #ifdef DEBUG_ZLIB |
| 1467 | # include <ctype.h> |
| 1468 | #endif |
| 1469 | |
| 1470 | /* =========================================================================== |
| 1471 | * Constants |
| 1472 | */ |
| 1473 | |
| 1474 | #define MAX_BL_BITS 7 |
| 1475 | /* Bit length codes must not exceed MAX_BL_BITS bits */ |
| 1476 | |
| 1477 | #define END_BLOCK 256 |
| 1478 | /* end of block literal code */ |
| 1479 | |
| 1480 | #define REP_3_6 16 |
| 1481 | /* repeat previous bit length 3-6 times (2 bits of repeat count) */ |
| 1482 | |
| 1483 | #define REPZ_3_10 17 |
| 1484 | /* repeat a zero length 3-10 times (3 bits of repeat count) */ |
| 1485 | |
| 1486 | #define REPZ_11_138 18 |
| 1487 | /* repeat a zero length 11-138 times (7 bits of repeat count) */ |
| 1488 | |
| 1489 | local int extra_lbits[LENGTH_CODES] /* extra bits for each length code */ |
| 1490 | = {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}; |
| 1491 | |
| 1492 | local int extra_dbits[D_CODES] /* extra bits for each distance code */ |
| 1493 | = {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}; |
| 1494 | |
| 1495 | local int extra_blbits[BL_CODES]/* extra bits for each bit length code */ |
| 1496 | = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7}; |
| 1497 | |
| 1498 | local uch bl_order[BL_CODES] |
| 1499 | = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15}; |
| 1500 | /* The lengths of the bit length codes are sent in order of decreasing |
| 1501 | * probability, to avoid transmitting the lengths for unused bit length codes. |
| 1502 | */ |
| 1503 | |
| 1504 | #define Buf_size (8 * 2*sizeof(char)) |
| 1505 | /* Number of bits used within bi_buf. (bi_buf might be implemented on |
| 1506 | * more than 16 bits on some systems.) |
| 1507 | */ |
| 1508 | |
| 1509 | /* =========================================================================== |
| 1510 | * Local data. These are initialized only once. |
| 1511 | * To do: initialize at compile time to be completely reentrant. ??? |
| 1512 | */ |
| 1513 | |
| 1514 | local ct_data static_ltree[L_CODES+2]; |
| 1515 | /* The static literal tree. Since the bit lengths are imposed, there is no |
| 1516 | * need for the L_CODES extra codes used during heap construction. However |
| 1517 | * The codes 286 and 287 are needed to build a canonical tree (see ct_init |
| 1518 | * below). |
| 1519 | */ |
| 1520 | |
| 1521 | local ct_data static_dtree[D_CODES]; |
| 1522 | /* The static distance tree. (Actually a trivial tree since all codes use |
| 1523 | * 5 bits.) |
| 1524 | */ |
| 1525 | |
| 1526 | local uch dist_code[512]; |
| 1527 | /* distance codes. The first 256 values correspond to the distances |
| 1528 | * 3 .. 258, the last 256 values correspond to the top 8 bits of |
| 1529 | * the 15 bit distances. |
| 1530 | */ |
| 1531 | |
| 1532 | local uch length_code[MAX_MATCH-MIN_MATCH+1]; |
| 1533 | /* length code for each normalized match length (0 == MIN_MATCH) */ |
| 1534 | |
| 1535 | local int base_length[LENGTH_CODES]; |
| 1536 | /* First normalized length for each code (0 = MIN_MATCH) */ |
| 1537 | |
| 1538 | local int base_dist[D_CODES]; |
| 1539 | /* First normalized distance for each code (0 = distance of 1) */ |
| 1540 | |
| 1541 | struct static_tree_desc_s { |
| 1542 | ct_data *static_tree; /* static tree or NULL */ |
| 1543 | intf *extra_bits; /* extra bits for each code or NULL */ |
| 1544 | int extra_base; /* base index for extra_bits */ |
| 1545 | int elems; /* max number of elements in the tree */ |
| 1546 | int max_length; /* max bit length for the codes */ |
| 1547 | }; |
| 1548 | |
| 1549 | local static_tree_desc static_l_desc = |
| 1550 | {static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS}; |
| 1551 | |
| 1552 | local static_tree_desc static_d_desc = |
| 1553 | {static_dtree, extra_dbits, 0, D_CODES, MAX_BITS}; |
| 1554 | |
| 1555 | local static_tree_desc static_bl_desc = |
| 1556 | {(ct_data *)0, extra_blbits, 0, BL_CODES, MAX_BL_BITS}; |
| 1557 | |
| 1558 | /* =========================================================================== |
| 1559 | * Local (static) routines in this file. |
| 1560 | */ |
| 1561 | |
| 1562 | local void ct_static_init OF((void)); |
| 1563 | local void init_block OF((deflate_state *s)); |
| 1564 | local void pqdownheap OF((deflate_state *s, ct_data *tree, int k)); |
| 1565 | local void gen_bitlen OF((deflate_state *s, tree_desc *desc)); |
| 1566 | local void gen_codes OF((ct_data *tree, int max_code, ushf *bl_count)); |
| 1567 | local void build_tree OF((deflate_state *s, tree_desc *desc)); |
| 1568 | local void scan_tree OF((deflate_state *s, ct_data *tree, int max_code)); |
| 1569 | local void send_tree OF((deflate_state *s, ct_data *tree, int max_code)); |
| 1570 | local int build_bl_tree OF((deflate_state *s)); |
| 1571 | local void send_all_trees OF((deflate_state *s, int lcodes, int dcodes, |
| 1572 | int blcodes)); |
| 1573 | local void compress_block OF((deflate_state *s, ct_data *ltree, |
| 1574 | ct_data *dtree)); |
| 1575 | local void set_data_type OF((deflate_state *s)); |
| 1576 | local unsigned bi_reverse OF((unsigned value, int length)); |
| 1577 | local void bi_windup OF((deflate_state *s)); |
| 1578 | local void bi_flush OF((deflate_state *s)); |
| 1579 | local void copy_block OF((deflate_state *s, charf *buf, unsigned len, |
| 1580 | int header)); |
| 1581 | |
| 1582 | #ifndef DEBUG_ZLIB |
| 1583 | # define send_code(s, c, tree) send_bits(s, tree[c].Code, tree[c].Len) |
| 1584 | /* Send a code of the given tree. c and tree must not have side effects */ |
| 1585 | |
| 1586 | #else /* DEBUG_ZLIB */ |
| 1587 | # define send_code(s, c, tree) \ |
| 1588 | { if (verbose>1) fprintf(stderr,"\ncd %3d ",(c)); \ |
| 1589 | send_bits(s, tree[c].Code, tree[c].Len); } |
| 1590 | #endif |
| 1591 | |
| 1592 | #define d_code(dist) \ |
| 1593 | ((dist) < 256 ? dist_code[dist] : dist_code[256+((dist)>>7)]) |
| 1594 | /* Mapping from a distance to a distance code. dist is the distance - 1 and |
| 1595 | * must not have side effects. dist_code[256] and dist_code[257] are never |
| 1596 | * used. |
| 1597 | */ |
| 1598 | |
| 1599 | /* =========================================================================== |
| 1600 | * Output a short LSB first on the stream. |
| 1601 | * IN assertion: there is enough room in pendingBuf. |
| 1602 | */ |
| 1603 | #define put_short(s, w) { \ |
| 1604 | put_byte(s, (uch)((w) & 0xff)); \ |
| 1605 | put_byte(s, (uch)((ush)(w) >> 8)); \ |
| 1606 | } |
| 1607 | |
| 1608 | /* =========================================================================== |
| 1609 | * Send a value on a given number of bits. |
| 1610 | * IN assertion: length <= 16 and value fits in length bits. |
| 1611 | */ |
| 1612 | #ifdef DEBUG_ZLIB |
| 1613 | local void send_bits OF((deflate_state *s, int value, int length)); |
| 1614 | |
| 1615 | local void send_bits(s, value, length) |
| 1616 | deflate_state *s; |
| 1617 | int value; /* value to send */ |
| 1618 | int length; /* number of bits */ |
| 1619 | { |
| 1620 | Tracev((stderr," l %2d v %4x ", length, value)); |
| 1621 | Assert(length > 0 && length <= 15, "invalid length"); |
| 1622 | s->bits_sent += (ulg)length; |
| 1623 | |
| 1624 | /* If not enough room in bi_buf, use (valid) bits from bi_buf and |
| 1625 | * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid)) |
| 1626 | * unused bits in value. |
| 1627 | */ |
| 1628 | if (s->bi_valid > (int)Buf_size - length) { |
| 1629 | s->bi_buf |= (value << s->bi_valid); |
| 1630 | put_short(s, s->bi_buf); |
| 1631 | s->bi_buf = (ush)value >> (Buf_size - s->bi_valid); |
| 1632 | s->bi_valid += length - Buf_size; |
| 1633 | } else { |
| 1634 | s->bi_buf |= value << s->bi_valid; |
| 1635 | s->bi_valid += length; |
| 1636 | } |
| 1637 | } |
| 1638 | #else /* !DEBUG_ZLIB */ |
| 1639 | |
| 1640 | #define send_bits(s, value, length) \ |
| 1641 | { int len = length;\ |
| 1642 | if (s->bi_valid > (int)Buf_size - len) {\ |
| 1643 | int val = value;\ |
| 1644 | s->bi_buf |= (val << s->bi_valid);\ |
| 1645 | put_short(s, s->bi_buf);\ |
| 1646 | s->bi_buf = (ush)val >> (Buf_size - s->bi_valid);\ |
| 1647 | s->bi_valid += len - Buf_size;\ |
| 1648 | } else {\ |
| 1649 | s->bi_buf |= (value) << s->bi_valid;\ |
| 1650 | s->bi_valid += len;\ |
| 1651 | }\ |
| 1652 | } |
| 1653 | #endif /* DEBUG_ZLIB */ |
| 1654 | |
| 1655 | |
| 1656 | /* the arguments must not have side effects */ |
| 1657 | |
| 1658 | /* =========================================================================== |
| 1659 | * Initialize the various 'constant' tables. |
| 1660 | * To do: do this at compile time. |
| 1661 | */ |
| 1662 | local void ct_static_init() |
| 1663 | { |
| 1664 | int n; /* iterates over tree elements */ |
| 1665 | int bits; /* bit counter */ |
| 1666 | int length; /* length value */ |
| 1667 | int code; /* code value */ |
| 1668 | int dist; /* distance index */ |
| 1669 | ush bl_count[MAX_BITS+1]; |
| 1670 | /* number of codes at each bit length for an optimal tree */ |
| 1671 | |
| 1672 | /* Initialize the mapping length (0..255) -> length code (0..28) */ |
| 1673 | length = 0; |
| 1674 | for (code = 0; code < LENGTH_CODES-1; code++) { |
| 1675 | base_length[code] = length; |
| 1676 | for (n = 0; n < (1<<extra_lbits[code]); n++) { |
| 1677 | length_code[length++] = (uch)code; |
| 1678 | } |
| 1679 | } |
| 1680 | Assert (length == 256, "ct_static_init: length != 256"); |
| 1681 | /* Note that the length 255 (match length 258) can be represented |
| 1682 | * in two different ways: code 284 + 5 bits or code 285, so we |
| 1683 | * overwrite length_code[255] to use the best encoding: |
| 1684 | */ |
| 1685 | length_code[length-1] = (uch)code; |
| 1686 | |
| 1687 | /* Initialize the mapping dist (0..32K) -> dist code (0..29) */ |
| 1688 | dist = 0; |
| 1689 | for (code = 0 ; code < 16; code++) { |
| 1690 | base_dist[code] = dist; |
| 1691 | for (n = 0; n < (1<<extra_dbits[code]); n++) { |
| 1692 | dist_code[dist++] = (uch)code; |
| 1693 | } |
| 1694 | } |
| 1695 | Assert (dist == 256, "ct_static_init: dist != 256"); |
| 1696 | dist >>= 7; /* from now on, all distances are divided by 128 */ |
| 1697 | for ( ; code < D_CODES; code++) { |
| 1698 | base_dist[code] = dist << 7; |
| 1699 | for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) { |
| 1700 | dist_code[256 + dist++] = (uch)code; |
| 1701 | } |
| 1702 | } |
| 1703 | Assert (dist == 256, "ct_static_init: 256+dist != 512"); |
| 1704 | |
| 1705 | /* Construct the codes of the static literal tree */ |
| 1706 | for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0; |
| 1707 | n = 0; |
| 1708 | while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++; |
| 1709 | while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++; |
| 1710 | while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++; |
| 1711 | while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++; |
| 1712 | /* Codes 286 and 287 do not exist, but we must include them in the |
| 1713 | * tree construction to get a canonical Huffman tree (longest code |
| 1714 | * all ones) |
| 1715 | */ |
| 1716 | gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count); |
| 1717 | |
| 1718 | /* The static distance tree is trivial: */ |
| 1719 | for (n = 0; n < D_CODES; n++) { |
| 1720 | static_dtree[n].Len = 5; |
| 1721 | static_dtree[n].Code = bi_reverse(n, 5); |
| 1722 | } |
| 1723 | } |
| 1724 | |
| 1725 | /* =========================================================================== |
| 1726 | * Initialize the tree data structures for a new zlib stream. |
| 1727 | */ |
| 1728 | local void ct_init(s) |
| 1729 | deflate_state *s; |
| 1730 | { |
| 1731 | if (static_dtree[0].Len == 0) { |
| 1732 | ct_static_init(); /* To do: at compile time */ |
| 1733 | } |
| 1734 | |
| 1735 | s->compressed_len = 0L; |
| 1736 | |
| 1737 | s->l_desc.dyn_tree = s->dyn_ltree; |
| 1738 | s->l_desc.stat_desc = &static_l_desc; |
| 1739 | |
| 1740 | s->d_desc.dyn_tree = s->dyn_dtree; |
| 1741 | s->d_desc.stat_desc = &static_d_desc; |
| 1742 | |
| 1743 | s->bl_desc.dyn_tree = s->bl_tree; |
| 1744 | s->bl_desc.stat_desc = &static_bl_desc; |
| 1745 | |
| 1746 | s->bi_buf = 0; |
| 1747 | s->bi_valid = 0; |
| 1748 | s->last_eob_len = 8; /* enough lookahead for inflate */ |
| 1749 | #ifdef DEBUG_ZLIB |
| 1750 | s->bits_sent = 0L; |
| 1751 | #endif |
| 1752 | s->blocks_in_packet = 0; |
| 1753 | |
| 1754 | /* Initialize the first block of the first file: */ |
| 1755 | init_block(s); |
| 1756 | } |
| 1757 | |
| 1758 | /* =========================================================================== |
| 1759 | * Initialize a new block. |
| 1760 | */ |
| 1761 | local void init_block(s) |
| 1762 | deflate_state *s; |
| 1763 | { |
| 1764 | int n; /* iterates over tree elements */ |
| 1765 | |
| 1766 | /* Initialize the trees. */ |
| 1767 | for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0; |
| 1768 | for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0; |
| 1769 | for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0; |
| 1770 | |
| 1771 | s->dyn_ltree[END_BLOCK].Freq = 1; |
| 1772 | s->opt_len = s->static_len = 0L; |
| 1773 | s->last_lit = s->matches = 0; |
| 1774 | } |
| 1775 | |
| 1776 | #define SMALLEST 1 |
| 1777 | /* Index within the heap array of least frequent node in the Huffman tree */ |
| 1778 | |
| 1779 | |
| 1780 | /* =========================================================================== |
| 1781 | * Remove the smallest element from the heap and recreate the heap with |
| 1782 | * one less element. Updates heap and heap_len. |
| 1783 | */ |
| 1784 | #define pqremove(s, tree, top) \ |
| 1785 | {\ |
| 1786 | top = s->heap[SMALLEST]; \ |
| 1787 | s->heap[SMALLEST] = s->heap[s->heap_len--]; \ |
| 1788 | pqdownheap(s, tree, SMALLEST); \ |
| 1789 | } |
| 1790 | |
| 1791 | /* =========================================================================== |
| 1792 | * Compares to subtrees, using the tree depth as tie breaker when |
| 1793 | * the subtrees have equal frequency. This minimizes the worst case length. |
| 1794 | */ |
| 1795 | #define smaller(tree, n, m, depth) \ |
| 1796 | (tree[n].Freq < tree[m].Freq || \ |
| 1797 | (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m])) |
| 1798 | |
| 1799 | /* =========================================================================== |
| 1800 | * Restore the heap property by moving down the tree starting at node k, |
| 1801 | * exchanging a node with the smallest of its two sons if necessary, stopping |
| 1802 | * when the heap property is re-established (each father smaller than its |
| 1803 | * two sons). |
| 1804 | */ |
| 1805 | local void pqdownheap(s, tree, k) |
| 1806 | deflate_state *s; |
| 1807 | ct_data *tree; /* the tree to restore */ |
| 1808 | int k; /* node to move down */ |
| 1809 | { |
| 1810 | int v = s->heap[k]; |
| 1811 | int j = k << 1; /* left son of k */ |
| 1812 | while (j <= s->heap_len) { |
| 1813 | /* Set j to the smallest of the two sons: */ |
| 1814 | if (j < s->heap_len && |
| 1815 | smaller(tree, s->heap[j+1], s->heap[j], s->depth)) { |
| 1816 | j++; |
| 1817 | } |
| 1818 | /* Exit if v is smaller than both sons */ |
| 1819 | if (smaller(tree, v, s->heap[j], s->depth)) break; |
| 1820 | |
| 1821 | /* Exchange v with the smallest son */ |
| 1822 | s->heap[k] = s->heap[j]; k = j; |
| 1823 | |
| 1824 | /* And continue down the tree, setting j to the left son of k */ |
| 1825 | j <<= 1; |
| 1826 | } |
| 1827 | s->heap[k] = v; |
| 1828 | } |
| 1829 | |
| 1830 | /* =========================================================================== |
| 1831 | * Compute the optimal bit lengths for a tree and update the total bit length |
| 1832 | * for the current block. |
| 1833 | * IN assertion: the fields freq and dad are set, heap[heap_max] and |
| 1834 | * above are the tree nodes sorted by increasing frequency. |
| 1835 | * OUT assertions: the field len is set to the optimal bit length, the |
| 1836 | * array bl_count contains the frequencies for each bit length. |
| 1837 | * The length opt_len is updated; static_len is also updated if stree is |
| 1838 | * not null. |
| 1839 | */ |
| 1840 | local void gen_bitlen(s, desc) |
| 1841 | deflate_state *s; |
| 1842 | tree_desc *desc; /* the tree descriptor */ |
| 1843 | { |
| 1844 | ct_data *tree = desc->dyn_tree; |
| 1845 | int max_code = desc->max_code; |
| 1846 | ct_data *stree = desc->stat_desc->static_tree; |
| 1847 | intf *extra = desc->stat_desc->extra_bits; |
| 1848 | int base = desc->stat_desc->extra_base; |
| 1849 | int max_length = desc->stat_desc->max_length; |
| 1850 | int h; /* heap index */ |
| 1851 | int n, m; /* iterate over the tree elements */ |
| 1852 | int bits; /* bit length */ |
| 1853 | int xbits; /* extra bits */ |
| 1854 | ush f; /* frequency */ |
| 1855 | int overflow = 0; /* number of elements with bit length too large */ |
| 1856 | |
| 1857 | for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0; |
| 1858 | |
| 1859 | /* In a first pass, compute the optimal bit lengths (which may |
| 1860 | * overflow in the case of the bit length tree). |
| 1861 | */ |
| 1862 | tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */ |
| 1863 | |
| 1864 | for (h = s->heap_max+1; h < HEAP_SIZE; h++) { |
| 1865 | n = s->heap[h]; |
| 1866 | bits = tree[tree[n].Dad].Len + 1; |
| 1867 | if (bits > max_length) bits = max_length, overflow++; |
| 1868 | tree[n].Len = (ush)bits; |
| 1869 | /* We overwrite tree[n].Dad which is no longer needed */ |
| 1870 | |
| 1871 | if (n > max_code) continue; /* not a leaf node */ |
| 1872 | |
| 1873 | s->bl_count[bits]++; |
| 1874 | xbits = 0; |
| 1875 | if (n >= base) xbits = extra[n-base]; |
| 1876 | f = tree[n].Freq; |
| 1877 | s->opt_len += (ulg)f * (bits + xbits); |
| 1878 | if (stree) s->static_len += (ulg)f * (stree[n].Len + xbits); |
| 1879 | } |
| 1880 | if (overflow == 0) return; |
| 1881 | |
| 1882 | Trace((stderr,"\nbit length overflow\n")); |
| 1883 | /* This happens for example on obj2 and pic of the Calgary corpus */ |
| 1884 | |
| 1885 | /* Find the first bit length which could increase: */ |
| 1886 | do { |
| 1887 | bits = max_length-1; |
| 1888 | while (s->bl_count[bits] == 0) bits--; |
| 1889 | s->bl_count[bits]--; /* move one leaf down the tree */ |
| 1890 | s->bl_count[bits+1] += 2; /* move one overflow item as its brother */ |
| 1891 | s->bl_count[max_length]--; |
| 1892 | /* The brother of the overflow item also moves one step up, |
| 1893 | * but this does not affect bl_count[max_length] |
| 1894 | */ |
| 1895 | overflow -= 2; |
| 1896 | } while (overflow > 0); |
| 1897 | |
| 1898 | /* Now recompute all bit lengths, scanning in increasing frequency. |
| 1899 | * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all |
| 1900 | * lengths instead of fixing only the wrong ones. This idea is taken |
| 1901 | * from 'ar' written by Haruhiko Okumura.) |
| 1902 | */ |
| 1903 | for (bits = max_length; bits != 0; bits--) { |
| 1904 | n = s->bl_count[bits]; |
| 1905 | while (n != 0) { |
| 1906 | m = s->heap[--h]; |
| 1907 | if (m > max_code) continue; |
| 1908 | if (tree[m].Len != (unsigned) bits) { |
| 1909 | Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits)); |
| 1910 | s->opt_len += ((Long)bits - (Long)tree[m].Len) |
| 1911 | *(Long)tree[m].Freq; |
| 1912 | tree[m].Len = (ush)bits; |
| 1913 | } |
| 1914 | n--; |
| 1915 | } |
| 1916 | } |
| 1917 | } |
| 1918 | |
| 1919 | /* =========================================================================== |
| 1920 | * Generate the codes for a given tree and bit counts (which need not be |
| 1921 | * optimal). |
| 1922 | * IN assertion: the array bl_count contains the bit length statistics for |
| 1923 | * the given tree and the field len is set for all tree elements. |
| 1924 | * OUT assertion: the field code is set for all tree elements of non |
| 1925 | * zero code length. |
| 1926 | */ |
| 1927 | local void gen_codes (tree, max_code, bl_count) |
| 1928 | ct_data *tree; /* the tree to decorate */ |
| 1929 | int max_code; /* largest code with non zero frequency */ |
| 1930 | ushf *bl_count; /* number of codes at each bit length */ |
| 1931 | { |
| 1932 | ush next_code[MAX_BITS+1]; /* next code value for each bit length */ |
| 1933 | ush code = 0; /* running code value */ |
| 1934 | int bits; /* bit index */ |
| 1935 | int n; /* code index */ |
| 1936 | |
| 1937 | /* The distribution counts are first used to generate the code values |
| 1938 | * without bit reversal. |
| 1939 | */ |
| 1940 | for (bits = 1; bits <= MAX_BITS; bits++) { |
| 1941 | next_code[bits] = code = (code + bl_count[bits-1]) << 1; |
| 1942 | } |
| 1943 | /* Check that the bit counts in bl_count are consistent. The last code |
| 1944 | * must be all ones. |
| 1945 | */ |
| 1946 | Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1, |
| 1947 | "inconsistent bit counts"); |
| 1948 | Tracev((stderr,"\ngen_codes: max_code %d ", max_code)); |
| 1949 | |
| 1950 | for (n = 0; n <= max_code; n++) { |
| 1951 | int len = tree[n].Len; |
| 1952 | if (len == 0) continue; |
| 1953 | /* Now reverse the bits */ |
| 1954 | tree[n].Code = bi_reverse(next_code[len]++, len); |
| 1955 | |
| 1956 | Tracec(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ", |
| 1957 | n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1)); |
| 1958 | } |
| 1959 | } |
| 1960 | |
| 1961 | /* =========================================================================== |
| 1962 | * Construct one Huffman tree and assigns the code bit strings and lengths. |
| 1963 | * Update the total bit length for the current block. |
| 1964 | * IN assertion: the field freq is set for all tree elements. |
| 1965 | * OUT assertions: the fields len and code are set to the optimal bit length |
| 1966 | * and corresponding code. The length opt_len is updated; static_len is |
| 1967 | * also updated if stree is not null. The field max_code is set. |
| 1968 | */ |
| 1969 | local void build_tree(s, desc) |
| 1970 | deflate_state *s; |
| 1971 | tree_desc *desc; /* the tree descriptor */ |
| 1972 | { |
| 1973 | ct_data *tree = desc->dyn_tree; |
| 1974 | ct_data *stree = desc->stat_desc->static_tree; |
| 1975 | int elems = desc->stat_desc->elems; |
| 1976 | int n, m; /* iterate over heap elements */ |
| 1977 | int max_code = -1; /* largest code with non zero frequency */ |
| 1978 | int node; /* new node being created */ |
| 1979 | |
| 1980 | /* Construct the initial heap, with least frequent element in |
| 1981 | * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1]. |
| 1982 | * heap[0] is not used. |
| 1983 | */ |
| 1984 | s->heap_len = 0, s->heap_max = HEAP_SIZE; |
| 1985 | |
| 1986 | for (n = 0; n < elems; n++) { |
| 1987 | if (tree[n].Freq != 0) { |
| 1988 | s->heap[++(s->heap_len)] = max_code = n; |
| 1989 | s->depth[n] = 0; |
| 1990 | } else { |
| 1991 | tree[n].Len = 0; |
| 1992 | } |
| 1993 | } |
| 1994 | |
| 1995 | /* The pkzip format requires that at least one distance code exists, |
| 1996 | * and that at least one bit should be sent even if there is only one |
| 1997 | * possible code. So to avoid special checks later on we force at least |
| 1998 | * two codes of non zero frequency. |
| 1999 | */ |
| 2000 | while (s->heap_len < 2) { |
| 2001 | node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0); |
| 2002 | tree[node].Freq = 1; |
| 2003 | s->depth[node] = 0; |
| 2004 | s->opt_len--; if (stree) s->static_len -= stree[node].Len; |
| 2005 | /* node is 0 or 1 so it does not have extra bits */ |
| 2006 | } |
| 2007 | desc->max_code = max_code; |
| 2008 | |
| 2009 | /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree, |
| 2010 | * establish sub-heaps of increasing lengths: |
| 2011 | */ |
| 2012 | for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n); |
| 2013 | |
| 2014 | /* Construct the Huffman tree by repeatedly combining the least two |
| 2015 | * frequent nodes. |
| 2016 | */ |
| 2017 | node = elems; /* next internal node of the tree */ |
| 2018 | do { |
| 2019 | pqremove(s, tree, n); /* n = node of least frequency */ |
| 2020 | m = s->heap[SMALLEST]; /* m = node of next least frequency */ |
| 2021 | |
| 2022 | s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */ |
| 2023 | s->heap[--(s->heap_max)] = m; |
| 2024 | |
| 2025 | /* Create a new node father of n and m */ |
| 2026 | tree[node].Freq = tree[n].Freq + tree[m].Freq; |
| 2027 | s->depth[node] = (uch) (MAX(s->depth[n], s->depth[m]) + 1); |
| 2028 | tree[n].Dad = tree[m].Dad = (ush)node; |
| 2029 | #ifdef DUMP_BL_TREE |
| 2030 | if (tree == s->bl_tree) { |
| 2031 | fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)", |
| 2032 | node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq); |
| 2033 | } |
| 2034 | #endif |
| 2035 | /* and insert the new node in the heap */ |
| 2036 | s->heap[SMALLEST] = node++; |
| 2037 | pqdownheap(s, tree, SMALLEST); |
| 2038 | |
| 2039 | } while (s->heap_len >= 2); |
| 2040 | |
| 2041 | s->heap[--(s->heap_max)] = s->heap[SMALLEST]; |
| 2042 | |
| 2043 | /* At this point, the fields freq and dad are set. We can now |
| 2044 | * generate the bit lengths. |
| 2045 | */ |
| 2046 | gen_bitlen(s, (tree_desc *)desc); |
| 2047 | |
| 2048 | /* The field len is now set, we can generate the bit codes */ |
| 2049 | gen_codes ((ct_data *)tree, max_code, s->bl_count); |
| 2050 | } |
| 2051 | |
| 2052 | /* =========================================================================== |
| 2053 | * Scan a literal or distance tree to determine the frequencies of the codes |
| 2054 | * in the bit length tree. |
| 2055 | */ |
| 2056 | local void scan_tree (s, tree, max_code) |
| 2057 | deflate_state *s; |
| 2058 | ct_data *tree; /* the tree to be scanned */ |
| 2059 | int max_code; /* and its largest code of non zero frequency */ |
| 2060 | { |
| 2061 | int n; /* iterates over all tree elements */ |
| 2062 | int prevlen = -1; /* last emitted length */ |
| 2063 | int curlen; /* length of current code */ |
| 2064 | int nextlen = tree[0].Len; /* length of next code */ |
| 2065 | int count = 0; /* repeat count of the current code */ |
| 2066 | int max_count = 7; /* max repeat count */ |
| 2067 | int min_count = 4; /* min repeat count */ |
| 2068 | |
| 2069 | if (nextlen == 0) max_count = 138, min_count = 3; |
| 2070 | tree[max_code+1].Len = (ush)0xffff; /* guard */ |
| 2071 | |
| 2072 | for (n = 0; n <= max_code; n++) { |
| 2073 | curlen = nextlen; nextlen = tree[n+1].Len; |
| 2074 | if (++count < max_count && curlen == nextlen) { |
| 2075 | continue; |
| 2076 | } else if (count < min_count) { |
| 2077 | s->bl_tree[curlen].Freq += count; |
| 2078 | } else if (curlen != 0) { |
| 2079 | if (curlen != prevlen) s->bl_tree[curlen].Freq++; |
| 2080 | s->bl_tree[REP_3_6].Freq++; |
| 2081 | } else if (count <= 10) { |
| 2082 | s->bl_tree[REPZ_3_10].Freq++; |
| 2083 | } else { |
| 2084 | s->bl_tree[REPZ_11_138].Freq++; |
| 2085 | } |
| 2086 | count = 0; prevlen = curlen; |
| 2087 | if (nextlen == 0) { |
| 2088 | max_count = 138, min_count = 3; |
| 2089 | } else if (curlen == nextlen) { |
| 2090 | max_count = 6, min_count = 3; |
| 2091 | } else { |
| 2092 | max_count = 7, min_count = 4; |
| 2093 | } |
| 2094 | } |
| 2095 | } |
| 2096 | |
| 2097 | /* =========================================================================== |
| 2098 | * Send a literal or distance tree in compressed form, using the codes in |
| 2099 | * bl_tree. |
| 2100 | */ |
| 2101 | local void send_tree (s, tree, max_code) |
| 2102 | deflate_state *s; |
| 2103 | ct_data *tree; /* the tree to be scanned */ |
| 2104 | int max_code; /* and its largest code of non zero frequency */ |
| 2105 | { |
| 2106 | int n; /* iterates over all tree elements */ |
| 2107 | int prevlen = -1; /* last emitted length */ |
| 2108 | int curlen; /* length of current code */ |
| 2109 | int nextlen = tree[0].Len; /* length of next code */ |
| 2110 | int count = 0; /* repeat count of the current code */ |
| 2111 | int max_count = 7; /* max repeat count */ |
| 2112 | int min_count = 4; /* min repeat count */ |
| 2113 | |
| 2114 | /* tree[max_code+1].Len = -1; */ /* guard already set */ |
| 2115 | if (nextlen == 0) max_count = 138, min_count = 3; |
| 2116 | |
| 2117 | for (n = 0; n <= max_code; n++) { |
| 2118 | curlen = nextlen; nextlen = tree[n+1].Len; |
| 2119 | if (++count < max_count && curlen == nextlen) { |
| 2120 | continue; |
| 2121 | } else if (count < min_count) { |
| 2122 | do { send_code(s, curlen, s->bl_tree); } while (--count != 0); |
| 2123 | |
| 2124 | } else if (curlen != 0) { |
| 2125 | if (curlen != prevlen) { |
| 2126 | send_code(s, curlen, s->bl_tree); count--; |
| 2127 | } |
| 2128 | Assert(count >= 3 && count <= 6, " 3_6?"); |
| 2129 | send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2); |
| 2130 | |
| 2131 | } else if (count <= 10) { |
| 2132 | send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3); |
| 2133 | |
| 2134 | } else { |
| 2135 | send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7); |
| 2136 | } |
| 2137 | count = 0; prevlen = curlen; |
| 2138 | if (nextlen == 0) { |
| 2139 | max_count = 138, min_count = 3; |
| 2140 | } else if (curlen == nextlen) { |
| 2141 | max_count = 6, min_count = 3; |
| 2142 | } else { |
| 2143 | max_count = 7, min_count = 4; |
| 2144 | } |
| 2145 | } |
| 2146 | } |
| 2147 | |
| 2148 | /* =========================================================================== |
| 2149 | * Construct the Huffman tree for the bit lengths and return the index in |
| 2150 | * bl_order of the last bit length code to send. |
| 2151 | */ |
| 2152 | local int build_bl_tree(s) |
| 2153 | deflate_state *s; |
| 2154 | { |
| 2155 | int max_blindex; /* index of last bit length code of non zero freq */ |
| 2156 | |
| 2157 | /* Determine the bit length frequencies for literal and distance trees */ |
| 2158 | scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code); |
| 2159 | scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code); |
| 2160 | |
| 2161 | /* Build the bit length tree: */ |
| 2162 | build_tree(s, (tree_desc *)(&(s->bl_desc))); |
| 2163 | /* opt_len now includes the length of the tree representations, except |
| 2164 | * the lengths of the bit lengths codes and the 5+5+4 bits for the counts. |
| 2165 | */ |
| 2166 | |
| 2167 | /* Determine the number of bit length codes to send. The pkzip format |
| 2168 | * requires that at least 4 bit length codes be sent. (appnote.txt says |
| 2169 | * 3 but the actual value used is 4.) |
| 2170 | */ |
| 2171 | for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) { |
| 2172 | if (s->bl_tree[bl_order[max_blindex]].Len != 0) break; |
| 2173 | } |
| 2174 | /* Update opt_len to include the bit length tree and counts */ |
| 2175 | s->opt_len += 3*(max_blindex+1) + 5+5+4; |
| 2176 | Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld", |
| 2177 | s->opt_len, s->static_len)); |
| 2178 | |
| 2179 | return max_blindex; |
| 2180 | } |
| 2181 | |
| 2182 | /* =========================================================================== |
| 2183 | * Send the header for a block using dynamic Huffman trees: the counts, the |
| 2184 | * lengths of the bit length codes, the literal tree and the distance tree. |
| 2185 | * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4. |
| 2186 | */ |
| 2187 | local void send_all_trees(s, lcodes, dcodes, blcodes) |
| 2188 | deflate_state *s; |
| 2189 | int lcodes, dcodes, blcodes; /* number of codes for each tree */ |
| 2190 | { |
| 2191 | int rank; /* index in bl_order */ |
| 2192 | |
| 2193 | Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes"); |
| 2194 | Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES, |
| 2195 | "too many codes"); |
| 2196 | Tracev((stderr, "\nbl counts: ")); |
| 2197 | send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */ |
| 2198 | send_bits(s, dcodes-1, 5); |
| 2199 | send_bits(s, blcodes-4, 4); /* not -3 as stated in appnote.txt */ |
| 2200 | for (rank = 0; rank < blcodes; rank++) { |
| 2201 | Tracev((stderr, "\nbl code %2d ", bl_order[rank])); |
| 2202 | send_bits(s, s->bl_tree[bl_order[rank]].Len, 3); |
| 2203 | } |
| 2204 | Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent)); |
| 2205 | |
| 2206 | send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */ |
| 2207 | Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent)); |
| 2208 | |
| 2209 | send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */ |
| 2210 | Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent)); |
| 2211 | } |
| 2212 | |
| 2213 | /* =========================================================================== |
| 2214 | * Send a stored block |
| 2215 | */ |
| 2216 | local void ct_stored_block(s, buf, stored_len, eof) |
| 2217 | deflate_state *s; |
| 2218 | charf *buf; /* input block */ |
| 2219 | ulg stored_len; /* length of input block */ |
| 2220 | int eof; /* true if this is the last block for a file */ |
| 2221 | { |
| 2222 | send_bits(s, (STORED_BLOCK<<1)+eof, 3); /* send block type */ |
| 2223 | s->compressed_len = (s->compressed_len + 3 + 7) & ~7L; |
| 2224 | s->compressed_len += (stored_len + 4) << 3; |
| 2225 | |
| 2226 | copy_block(s, buf, (unsigned)stored_len, 1); /* with header */ |
| 2227 | } |
| 2228 | |
| 2229 | /* Send just the `stored block' type code without any length bytes or data. |
| 2230 | */ |
| 2231 | local void ct_stored_type_only(s) |
| 2232 | deflate_state *s; |
| 2233 | { |
| 2234 | send_bits(s, (STORED_BLOCK << 1), 3); |
| 2235 | bi_windup(s); |
| 2236 | s->compressed_len = (s->compressed_len + 3) & ~7L; |
| 2237 | } |
| 2238 | |
| 2239 | |
| 2240 | /* =========================================================================== |
| 2241 | * Send one empty static block to give enough lookahead for inflate. |
| 2242 | * This takes 10 bits, of which 7 may remain in the bit buffer. |
| 2243 | * The current inflate code requires 9 bits of lookahead. If the EOB |
| 2244 | * code for the previous block was coded on 5 bits or less, inflate |
| 2245 | * may have only 5+3 bits of lookahead to decode this EOB. |
| 2246 | * (There are no problems if the previous block is stored or fixed.) |
| 2247 | */ |
| 2248 | local void ct_align(s) |
| 2249 | deflate_state *s; |
| 2250 | { |
| 2251 | send_bits(s, STATIC_TREES<<1, 3); |
| 2252 | send_code(s, END_BLOCK, static_ltree); |
| 2253 | s->compressed_len += 10L; /* 3 for block type, 7 for EOB */ |
| 2254 | bi_flush(s); |
| 2255 | /* Of the 10 bits for the empty block, we have already sent |
| 2256 | * (10 - bi_valid) bits. The lookahead for the EOB of the previous |
| 2257 | * block was thus its length plus what we have just sent. |
| 2258 | */ |
| 2259 | if (s->last_eob_len + 10 - s->bi_valid < 9) { |
| 2260 | send_bits(s, STATIC_TREES<<1, 3); |
| 2261 | send_code(s, END_BLOCK, static_ltree); |
| 2262 | s->compressed_len += 10L; |
| 2263 | bi_flush(s); |
| 2264 | } |
| 2265 | s->last_eob_len = 7; |
| 2266 | } |
| 2267 | |
| 2268 | /* =========================================================================== |
| 2269 | * Determine the best encoding for the current block: dynamic trees, static |
| 2270 | * trees or store, and output the encoded block to the zip file. This function |
| 2271 | * returns the total compressed length for the file so far. |
| 2272 | */ |
| 2273 | local ulg ct_flush_block(s, buf, stored_len, flush) |
| 2274 | deflate_state *s; |
| 2275 | charf *buf; /* input block, or NULL if too old */ |
| 2276 | ulg stored_len; /* length of input block */ |
| 2277 | int flush; /* Z_FINISH if this is the last block for a file */ |
| 2278 | { |
| 2279 | ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */ |
| 2280 | int max_blindex; /* index of last bit length code of non zero freq */ |
| 2281 | int eof = flush == Z_FINISH; |
| 2282 | |
| 2283 | ++s->blocks_in_packet; |
| 2284 | |
| 2285 | /* Check if the file is ascii or binary */ |
| 2286 | if (s->data_type == UNKNOWN) set_data_type(s); |
| 2287 | |
| 2288 | /* Construct the literal and distance trees */ |
| 2289 | build_tree(s, (tree_desc *)(&(s->l_desc))); |
| 2290 | Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len, |
| 2291 | s->static_len)); |
| 2292 | |
| 2293 | build_tree(s, (tree_desc *)(&(s->d_desc))); |
| 2294 | Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len, |
| 2295 | s->static_len)); |
| 2296 | /* At this point, opt_len and static_len are the total bit lengths of |
| 2297 | * the compressed block data, excluding the tree representations. |
| 2298 | */ |
| 2299 | |
| 2300 | /* Build the bit length tree for the above two trees, and get the index |
| 2301 | * in bl_order of the last bit length code to send. |
| 2302 | */ |
| 2303 | max_blindex = build_bl_tree(s); |
| 2304 | |
| 2305 | /* Determine the best encoding. Compute first the block length in bytes */ |
| 2306 | opt_lenb = (s->opt_len+3+7)>>3; |
| 2307 | static_lenb = (s->static_len+3+7)>>3; |
| 2308 | |
| 2309 | Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ", |
| 2310 | opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len, |
| 2311 | s->last_lit)); |
| 2312 | |
| 2313 | if (static_lenb <= opt_lenb) opt_lenb = static_lenb; |
| 2314 | |
| 2315 | /* If compression failed and this is the first and last block, |
| 2316 | * and if the .zip file can be seeked (to rewrite the local header), |
| 2317 | * the whole file is transformed into a stored file: |
| 2318 | */ |
| 2319 | #ifdef STORED_FILE_OK |
| 2320 | # ifdef FORCE_STORED_FILE |
| 2321 | if (eof && compressed_len == 0L) /* force stored file */ |
| 2322 | # else |
| 2323 | if (stored_len <= opt_lenb && eof && s->compressed_len==0L && seekable()) |
| 2324 | # endif |
| 2325 | { |
| 2326 | /* Since LIT_BUFSIZE <= 2*WSIZE, the input data must be there: */ |
| 2327 | if (buf == (charf*)0) error ("block vanished"); |
| 2328 | |
| 2329 | copy_block(buf, (unsigned)stored_len, 0); /* without header */ |
| 2330 | s->compressed_len = stored_len << 3; |
| 2331 | s->method = STORED; |
| 2332 | } else |
| 2333 | #endif /* STORED_FILE_OK */ |
| 2334 | |
| 2335 | #ifdef FORCE_STORED |
| 2336 | if (buf != (char*)0) /* force stored block */ |
| 2337 | #else |
| 2338 | if (stored_len+4 <= opt_lenb && buf != (char*)0) |
| 2339 | /* 4: two words for the lengths */ |
| 2340 | #endif |
| 2341 | { |
| 2342 | /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE. |
| 2343 | * Otherwise we can't have processed more than WSIZE input bytes since |
| 2344 | * the last block flush, because compression would have been |
| 2345 | * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to |
| 2346 | * transform a block into a stored block. |
| 2347 | */ |
| 2348 | ct_stored_block(s, buf, stored_len, eof); |
| 2349 | } else |
| 2350 | |
| 2351 | #ifdef FORCE_STATIC |
| 2352 | if (static_lenb >= 0) /* force static trees */ |
| 2353 | #else |
| 2354 | if (static_lenb == opt_lenb) |
| 2355 | #endif |
| 2356 | { |
| 2357 | send_bits(s, (STATIC_TREES<<1)+eof, 3); |
| 2358 | compress_block(s, (ct_data *)static_ltree, (ct_data *)static_dtree); |
| 2359 | s->compressed_len += 3 + s->static_len; |
| 2360 | } else { |
| 2361 | send_bits(s, (DYN_TREES<<1)+eof, 3); |
| 2362 | send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1, |
| 2363 | max_blindex+1); |
| 2364 | compress_block(s, (ct_data *)s->dyn_ltree, (ct_data *)s->dyn_dtree); |
| 2365 | s->compressed_len += 3 + s->opt_len; |
| 2366 | } |
| 2367 | Assert (s->compressed_len == s->bits_sent, "bad compressed size"); |
| 2368 | init_block(s); |
| 2369 | |
| 2370 | if (eof) { |
| 2371 | bi_windup(s); |
| 2372 | s->compressed_len += 7; /* align on byte boundary */ |
| 2373 | } |
| 2374 | Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3, |
| 2375 | s->compressed_len-7*eof)); |
| 2376 | |
| 2377 | return s->compressed_len >> 3; |
| 2378 | } |
| 2379 | |
| 2380 | /* =========================================================================== |
| 2381 | * Save the match info and tally the frequency counts. Return true if |
| 2382 | * the current block must be flushed. |
| 2383 | */ |
| 2384 | local int ct_tally (s, dist, lc) |
| 2385 | deflate_state *s; |
| 2386 | int dist; /* distance of matched string */ |
| 2387 | int lc; /* match length-MIN_MATCH or unmatched char (if dist==0) */ |
| 2388 | { |
| 2389 | s->d_buf[s->last_lit] = (ush)dist; |
| 2390 | s->l_buf[s->last_lit++] = (uch)lc; |
| 2391 | if (dist == 0) { |
| 2392 | /* lc is the unmatched char */ |
| 2393 | s->dyn_ltree[lc].Freq++; |
| 2394 | } else { |
| 2395 | s->matches++; |
| 2396 | /* Here, lc is the match length - MIN_MATCH */ |
| 2397 | dist--; /* dist = match distance - 1 */ |
| 2398 | Assert((ush)dist < (ush)MAX_DIST(s) && |
| 2399 | (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) && |
| 2400 | (ush)d_code(dist) < (ush)D_CODES, "ct_tally: bad match"); |
| 2401 | |
| 2402 | s->dyn_ltree[length_code[lc]+LITERALS+1].Freq++; |
| 2403 | s->dyn_dtree[d_code(dist)].Freq++; |
| 2404 | } |
| 2405 | |
| 2406 | /* Try to guess if it is profitable to stop the current block here */ |
| 2407 | if (s->level > 2 && (s->last_lit & 0xfff) == 0) { |
| 2408 | /* Compute an upper bound for the compressed length */ |
| 2409 | ulg out_length = (ulg)s->last_lit*8L; |
| 2410 | ulg in_length = (ulg)s->strstart - s->block_start; |
| 2411 | int dcode; |
| 2412 | for (dcode = 0; dcode < D_CODES; dcode++) { |
| 2413 | out_length += (ulg)s->dyn_dtree[dcode].Freq * |
| 2414 | (5L+extra_dbits[dcode]); |
| 2415 | } |
| 2416 | out_length >>= 3; |
| 2417 | Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ", |
| 2418 | s->last_lit, in_length, out_length, |
| 2419 | 100L - out_length*100L/in_length)); |
| 2420 | if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1; |
| 2421 | } |
| 2422 | return (s->last_lit == s->lit_bufsize-1); |
| 2423 | /* We avoid equality with lit_bufsize because of wraparound at 64K |
| 2424 | * on 16 bit machines and because stored blocks are restricted to |
| 2425 | * 64K-1 bytes. |
| 2426 | */ |
| 2427 | } |
| 2428 | |
| 2429 | /* =========================================================================== |
| 2430 | * Send the block data compressed using the given Huffman trees |
| 2431 | */ |
| 2432 | local void compress_block(s, ltree, dtree) |
| 2433 | deflate_state *s; |
| 2434 | ct_data *ltree; /* literal tree */ |
| 2435 | ct_data *dtree; /* distance tree */ |
| 2436 | { |
| 2437 | unsigned dist; /* distance of matched string */ |
| 2438 | int lc; /* match length or unmatched char (if dist == 0) */ |
| 2439 | unsigned lx = 0; /* running index in l_buf */ |
| 2440 | unsigned code; /* the code to send */ |
| 2441 | int extra; /* number of extra bits to send */ |
| 2442 | |
| 2443 | if (s->last_lit != 0) do { |
| 2444 | dist = s->d_buf[lx]; |
| 2445 | lc = s->l_buf[lx++]; |
| 2446 | if (dist == 0) { |
| 2447 | send_code(s, lc, ltree); /* send a literal byte */ |
| 2448 | Tracecv(isgraph(lc), (stderr," '%c' ", lc)); |
| 2449 | } else { |
| 2450 | /* Here, lc is the match length - MIN_MATCH */ |
| 2451 | code = length_code[lc]; |
| 2452 | send_code(s, code+LITERALS+1, ltree); /* send the length code */ |
| 2453 | extra = extra_lbits[code]; |
| 2454 | if (extra != 0) { |
| 2455 | lc -= base_length[code]; |
| 2456 | send_bits(s, lc, extra); /* send the extra length bits */ |
| 2457 | } |
| 2458 | dist--; /* dist is now the match distance - 1 */ |
| 2459 | code = d_code(dist); |
| 2460 | Assert (code < D_CODES, "bad d_code"); |
| 2461 | |
| 2462 | send_code(s, code, dtree); /* send the distance code */ |
| 2463 | extra = extra_dbits[code]; |
| 2464 | if (extra != 0) { |
| 2465 | dist -= base_dist[code]; |
| 2466 | send_bits(s, dist, extra); /* send the extra distance bits */ |
| 2467 | } |
| 2468 | } /* literal or match pair ? */ |
| 2469 | |
| 2470 | /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */ |
| 2471 | Assert(s->pending < s->lit_bufsize + 2*lx, "pendingBuf overflow"); |
| 2472 | |
| 2473 | } while (lx < s->last_lit); |
| 2474 | |
| 2475 | send_code(s, END_BLOCK, ltree); |
| 2476 | s->last_eob_len = ltree[END_BLOCK].Len; |
| 2477 | } |
| 2478 | |
| 2479 | /* =========================================================================== |
| 2480 | * Set the data type to ASCII or BINARY, using a crude approximation: |
| 2481 | * binary if more than 20% of the bytes are <= 6 or >= 128, ascii otherwise. |
| 2482 | * IN assertion: the fields freq of dyn_ltree are set and the total of all |
| 2483 | * frequencies does not exceed 64K (to fit in an int on 16 bit machines). |
| 2484 | */ |
| 2485 | local void set_data_type(s) |
| 2486 | deflate_state *s; |
| 2487 | { |
| 2488 | int n = 0; |
| 2489 | unsigned ascii_freq = 0; |
| 2490 | unsigned bin_freq = 0; |
| 2491 | while (n < 7) bin_freq += s->dyn_ltree[n++].Freq; |
| 2492 | while (n < 128) ascii_freq += s->dyn_ltree[n++].Freq; |
| 2493 | while (n < LITERALS) bin_freq += s->dyn_ltree[n++].Freq; |
| 2494 | s->data_type = (Byte)(bin_freq > (ascii_freq >> 2) ? BINARY : ASCII); |
| 2495 | } |
| 2496 | |
| 2497 | /* =========================================================================== |
| 2498 | * Reverse the first len bits of a code, using straightforward code (a faster |
| 2499 | * method would use a table) |
| 2500 | * IN assertion: 1 <= len <= 15 |
| 2501 | */ |
| 2502 | local unsigned bi_reverse(code, len) |
| 2503 | unsigned code; /* the value to invert */ |
| 2504 | int len; /* its bit length */ |
| 2505 | { |
| 2506 | register unsigned res = 0; |
| 2507 | do { |
| 2508 | res |= code & 1; |
| 2509 | code >>= 1, res <<= 1; |
| 2510 | } while (--len > 0); |
| 2511 | return res >> 1; |
| 2512 | } |
| 2513 | |
| 2514 | /* =========================================================================== |
| 2515 | * Flush the bit buffer, keeping at most 7 bits in it. |
| 2516 | */ |
| 2517 | local void bi_flush(s) |
| 2518 | deflate_state *s; |
| 2519 | { |
| 2520 | if (s->bi_valid == 16) { |
| 2521 | put_short(s, s->bi_buf); |
| 2522 | s->bi_buf = 0; |
| 2523 | s->bi_valid = 0; |
| 2524 | } else if (s->bi_valid >= 8) { |
| 2525 | put_byte(s, (Byte)s->bi_buf); |
| 2526 | s->bi_buf >>= 8; |
| 2527 | s->bi_valid -= 8; |
| 2528 | } |
| 2529 | } |
| 2530 | |
| 2531 | /* =========================================================================== |
| 2532 | * Flush the bit buffer and align the output on a byte boundary |
| 2533 | */ |
| 2534 | local void bi_windup(s) |
| 2535 | deflate_state *s; |
| 2536 | { |
| 2537 | if (s->bi_valid > 8) { |
| 2538 | put_short(s, s->bi_buf); |
| 2539 | } else if (s->bi_valid > 0) { |
| 2540 | put_byte(s, (Byte)s->bi_buf); |
| 2541 | } |
| 2542 | s->bi_buf = 0; |
| 2543 | s->bi_valid = 0; |
| 2544 | #ifdef DEBUG_ZLIB |
| 2545 | s->bits_sent = (s->bits_sent+7) & ~7; |
| 2546 | #endif |
| 2547 | } |
| 2548 | |
| 2549 | /* =========================================================================== |
| 2550 | * Copy a stored block, storing first the length and its |
| 2551 | * one's complement if requested. |
| 2552 | */ |
| 2553 | local void copy_block(s, buf, len, header) |
| 2554 | deflate_state *s; |
| 2555 | charf *buf; /* the input data */ |
| 2556 | unsigned len; /* its length */ |
| 2557 | int header; /* true if block header must be written */ |
| 2558 | { |
| 2559 | bi_windup(s); /* align on byte boundary */ |
| 2560 | s->last_eob_len = 8; /* enough lookahead for inflate */ |
| 2561 | |
| 2562 | if (header) { |
| 2563 | put_short(s, (ush)len); |
| 2564 | put_short(s, (ush)~len); |
| 2565 | #ifdef DEBUG_ZLIB |
| 2566 | s->bits_sent += 2*16; |
| 2567 | #endif |
| 2568 | } |
| 2569 | #ifdef DEBUG_ZLIB |
| 2570 | s->bits_sent += (ulg)len<<3; |
| 2571 | #endif |
| 2572 | while (len--) { |
| 2573 | put_byte(s, *buf++); |
| 2574 | } |
| 2575 | } |
| 2576 | |
| 2577 | |
| 2578 | /*+++++*/ |
| 2579 | /* infblock.h -- header to use infblock.c |
| 2580 | * Copyright (C) 1995 Mark Adler |
| 2581 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 2582 | */ |
| 2583 | |
| 2584 | /* WARNING: this file should *not* be used by applications. It is |
| 2585 | part of the implementation of the compression library and is |
| 2586 | subject to change. Applications should only use zlib.h. |
| 2587 | */ |
| 2588 | |
| 2589 | struct inflate_blocks_state; |
| 2590 | typedef struct inflate_blocks_state FAR inflate_blocks_statef; |
| 2591 | |
| 2592 | local inflate_blocks_statef * inflate_blocks_new OF(( |
| 2593 | z_stream *z, |
| 2594 | check_func c, /* check function */ |
| 2595 | uInt w)); /* window size */ |
| 2596 | |
| 2597 | local int inflate_blocks OF(( |
| 2598 | inflate_blocks_statef *, |
| 2599 | z_stream *, |
| 2600 | int)); /* initial return code */ |
| 2601 | |
| 2602 | local void inflate_blocks_reset OF(( |
| 2603 | inflate_blocks_statef *, |
| 2604 | z_stream *, |
| 2605 | uLongf *)); /* check value on output */ |
| 2606 | |
| 2607 | local int inflate_blocks_free OF(( |
| 2608 | inflate_blocks_statef *, |
| 2609 | z_stream *, |
| 2610 | uLongf *)); /* check value on output */ |
| 2611 | |
| 2612 | local int inflate_addhistory OF(( |
| 2613 | inflate_blocks_statef *, |
| 2614 | z_stream *)); |
| 2615 | |
| 2616 | local int inflate_packet_flush OF(( |
| 2617 | inflate_blocks_statef *)); |
| 2618 | |
| 2619 | /*+++++*/ |
| 2620 | /* inftrees.h -- header to use inftrees.c |
| 2621 | * Copyright (C) 1995 Mark Adler |
| 2622 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 2623 | */ |
| 2624 | |
| 2625 | /* WARNING: this file should *not* be used by applications. It is |
| 2626 | part of the implementation of the compression library and is |
| 2627 | subject to change. Applications should only use zlib.h. |
| 2628 | */ |
| 2629 | |
| 2630 | /* Huffman code lookup table entry--this entry is four bytes for machines |
| 2631 | that have 16-bit pointers (e.g. PC's in the small or medium model). */ |
| 2632 | |
| 2633 | typedef struct inflate_huft_s FAR inflate_huft; |
| 2634 | |
| 2635 | struct inflate_huft_s { |
| 2636 | union { |
| 2637 | struct { |
| 2638 | Byte Exop; /* number of extra bits or operation */ |
| 2639 | Byte Bits; /* number of bits in this code or subcode */ |
| 2640 | } what; |
| 2641 | uInt Nalloc; /* number of these allocated here */ |
| 2642 | Bytef *pad; /* pad structure to a power of 2 (4 bytes for */ |
| 2643 | } word; /* 16-bit, 8 bytes for 32-bit machines) */ |
| 2644 | union { |
| 2645 | uInt Base; /* literal, length base, or distance base */ |
| 2646 | inflate_huft *Next; /* pointer to next level of table */ |
| 2647 | } more; |
| 2648 | }; |
| 2649 | |
| 2650 | #ifdef DEBUG_ZLIB |
| 2651 | local uInt inflate_hufts; |
| 2652 | #endif |
| 2653 | |
| 2654 | local int inflate_trees_bits OF(( |
| 2655 | uIntf *, /* 19 code lengths */ |
| 2656 | uIntf *, /* bits tree desired/actual depth */ |
| 2657 | inflate_huft * FAR *, /* bits tree result */ |
| 2658 | z_stream *)); /* for zalloc, zfree functions */ |
| 2659 | |
| 2660 | local int inflate_trees_dynamic OF(( |
| 2661 | uInt, /* number of literal/length codes */ |
| 2662 | uInt, /* number of distance codes */ |
| 2663 | uIntf *, /* that many (total) code lengths */ |
| 2664 | uIntf *, /* literal desired/actual bit depth */ |
| 2665 | uIntf *, /* distance desired/actual bit depth */ |
| 2666 | inflate_huft * FAR *, /* literal/length tree result */ |
| 2667 | inflate_huft * FAR *, /* distance tree result */ |
| 2668 | z_stream *)); /* for zalloc, zfree functions */ |
| 2669 | |
| 2670 | local int inflate_trees_fixed OF(( |
| 2671 | uIntf *, /* literal desired/actual bit depth */ |
| 2672 | uIntf *, /* distance desired/actual bit depth */ |
| 2673 | inflate_huft * FAR *, /* literal/length tree result */ |
| 2674 | inflate_huft * FAR *)); /* distance tree result */ |
| 2675 | |
| 2676 | local int inflate_trees_free OF(( |
| 2677 | inflate_huft *, /* tables to free */ |
| 2678 | z_stream *)); /* for zfree function */ |
| 2679 | |
| 2680 | |
| 2681 | /*+++++*/ |
| 2682 | /* infcodes.h -- header to use infcodes.c |
| 2683 | * Copyright (C) 1995 Mark Adler |
| 2684 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 2685 | */ |
| 2686 | |
| 2687 | /* WARNING: this file should *not* be used by applications. It is |
| 2688 | part of the implementation of the compression library and is |
| 2689 | subject to change. Applications should only use zlib.h. |
| 2690 | */ |
| 2691 | |
| 2692 | struct inflate_codes_state; |
| 2693 | typedef struct inflate_codes_state FAR inflate_codes_statef; |
| 2694 | |
| 2695 | local inflate_codes_statef *inflate_codes_new OF(( |
| 2696 | uInt, uInt, |
| 2697 | inflate_huft *, inflate_huft *, |
| 2698 | z_stream *)); |
| 2699 | |
| 2700 | local int inflate_codes OF(( |
| 2701 | inflate_blocks_statef *, |
| 2702 | z_stream *, |
| 2703 | int)); |
| 2704 | |
| 2705 | local void inflate_codes_free OF(( |
| 2706 | inflate_codes_statef *, |
| 2707 | z_stream *)); |
| 2708 | |
| 2709 | |
| 2710 | /*+++++*/ |
| 2711 | /* inflate.c -- zlib interface to inflate modules |
| 2712 | * Copyright (C) 1995 Mark Adler |
| 2713 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 2714 | */ |
| 2715 | |
| 2716 | /* inflate private state */ |
| 2717 | struct internal_state { |
| 2718 | |
| 2719 | /* mode */ |
| 2720 | enum { |
| 2721 | METHOD, /* waiting for method byte */ |
| 2722 | FLAG, /* waiting for flag byte */ |
| 2723 | BLOCKS, /* decompressing blocks */ |
| 2724 | CHECK4, /* four check bytes to go */ |
| 2725 | CHECK3, /* three check bytes to go */ |
| 2726 | CHECK2, /* two check bytes to go */ |
| 2727 | CHECK1, /* one check byte to go */ |
| 2728 | DONE, /* finished check, done */ |
| 2729 | ZBAD} /* got an error--stay here */ |
| 2730 | mode; /* current inflate mode */ |
| 2731 | |
| 2732 | /* mode dependent information */ |
| 2733 | union { |
| 2734 | uInt method; /* if FLAGS, method byte */ |
| 2735 | struct { |
| 2736 | uLong was; /* computed check value */ |
| 2737 | uLong need; /* stream check value */ |
| 2738 | } check; /* if CHECK, check values to compare */ |
| 2739 | uInt marker; /* if ZBAD, inflateSync's marker bytes count */ |
| 2740 | } sub; /* submode */ |
| 2741 | |
| 2742 | /* mode independent information */ |
| 2743 | int nowrap; /* flag for no wrapper */ |
| 2744 | uInt wbits; /* log2(window size) (8..15, defaults to 15) */ |
| 2745 | inflate_blocks_statef |
| 2746 | *blocks; /* current inflate_blocks state */ |
| 2747 | |
| 2748 | }; |
| 2749 | |
| 2750 | |
| 2751 | int inflateReset(z) |
| 2752 | z_stream *z; |
| 2753 | { |
| 2754 | uLong c; |
| 2755 | |
| 2756 | if (z == Z_NULL || z->state == Z_NULL) |
| 2757 | return Z_STREAM_ERROR; |
| 2758 | z->total_in = z->total_out = 0; |
| 2759 | z->msg = Z_NULL; |
| 2760 | z->state->mode = z->state->nowrap ? BLOCKS : METHOD; |
| 2761 | inflate_blocks_reset(z->state->blocks, z, &c); |
| 2762 | Trace((stderr, "inflate: reset\n")); |
| 2763 | return Z_OK; |
| 2764 | } |
| 2765 | |
| 2766 | |
| 2767 | int inflateEnd(z) |
| 2768 | z_stream *z; |
| 2769 | { |
| 2770 | uLong c; |
| 2771 | |
| 2772 | if (z == Z_NULL || z->state == Z_NULL || z->zfree == Z_NULL) |
| 2773 | return Z_STREAM_ERROR; |
| 2774 | if (z->state->blocks != Z_NULL) |
| 2775 | inflate_blocks_free(z->state->blocks, z, &c); |
| 2776 | ZFREE(z, z->state, sizeof(struct internal_state)); |
| 2777 | z->state = Z_NULL; |
| 2778 | Trace((stderr, "inflate: end\n")); |
| 2779 | return Z_OK; |
| 2780 | } |
| 2781 | |
| 2782 | |
| 2783 | int inflateInit2(z, w) |
| 2784 | z_stream *z; |
| 2785 | int w; |
| 2786 | { |
| 2787 | /* initialize state */ |
| 2788 | if (z == Z_NULL) |
| 2789 | return Z_STREAM_ERROR; |
| 2790 | /* if (z->zalloc == Z_NULL) z->zalloc = zcalloc; */ |
| 2791 | /* if (z->zfree == Z_NULL) z->zfree = zcfree; */ |
| 2792 | if ((z->state = (struct internal_state FAR *) |
| 2793 | ZALLOC(z,1,sizeof(struct internal_state))) == Z_NULL) |
| 2794 | return Z_MEM_ERROR; |
| 2795 | z->state->blocks = Z_NULL; |
| 2796 | |
| 2797 | /* handle undocumented nowrap option (no zlib header or check) */ |
| 2798 | z->state->nowrap = 0; |
| 2799 | if (w < 0) |
| 2800 | { |
| 2801 | w = - w; |
| 2802 | z->state->nowrap = 1; |
| 2803 | } |
| 2804 | |
| 2805 | /* set window size */ |
| 2806 | if (w < 8 || w > 15) |
| 2807 | { |
| 2808 | inflateEnd(z); |
| 2809 | return Z_STREAM_ERROR; |
| 2810 | } |
| 2811 | z->state->wbits = (uInt)w; |
| 2812 | |
| 2813 | /* create inflate_blocks state */ |
| 2814 | if ((z->state->blocks = |
| 2815 | inflate_blocks_new(z, z->state->nowrap ? Z_NULL : adler32, 1 << w)) |
| 2816 | == Z_NULL) |
| 2817 | { |
| 2818 | inflateEnd(z); |
| 2819 | return Z_MEM_ERROR; |
| 2820 | } |
| 2821 | Trace((stderr, "inflate: allocated\n")); |
| 2822 | |
| 2823 | /* reset state */ |
| 2824 | inflateReset(z); |
| 2825 | return Z_OK; |
| 2826 | } |
| 2827 | |
| 2828 | |
| 2829 | int inflateInit(z) |
| 2830 | z_stream *z; |
| 2831 | { |
| 2832 | return inflateInit2(z, DEF_WBITS); |
| 2833 | } |
| 2834 | |
| 2835 | |
| 2836 | #define NEEDBYTE {if(z->avail_in==0)goto empty;r=Z_OK;} |
| 2837 | #define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++) |
| 2838 | |
| 2839 | int inflate(z, f) |
| 2840 | z_stream *z; |
| 2841 | int f; |
| 2842 | { |
| 2843 | int r; |
| 2844 | uInt b; |
| 2845 | |
| 2846 | if (z == Z_NULL || z->next_in == Z_NULL) |
| 2847 | return Z_STREAM_ERROR; |
| 2848 | r = Z_BUF_ERROR; |
| 2849 | while (1) switch (z->state->mode) |
| 2850 | { |
| 2851 | case METHOD: |
| 2852 | NEEDBYTE |
| 2853 | if (((z->state->sub.method = NEXTBYTE) & 0xf) != DEFLATED) |
| 2854 | { |
| 2855 | z->state->mode = ZBAD; |
| 2856 | z->msg = "unknown compression method"; |
| 2857 | z->state->sub.marker = 5; /* can't try inflateSync */ |
| 2858 | break; |
| 2859 | } |
| 2860 | if ((z->state->sub.method >> 4) + 8 > z->state->wbits) |
| 2861 | { |
| 2862 | z->state->mode = ZBAD; |
| 2863 | z->msg = "invalid window size"; |
| 2864 | z->state->sub.marker = 5; /* can't try inflateSync */ |
| 2865 | break; |
| 2866 | } |
| 2867 | z->state->mode = FLAG; |
| 2868 | case FLAG: |
| 2869 | NEEDBYTE |
| 2870 | if ((b = NEXTBYTE) & 0x20) |
| 2871 | { |
| 2872 | z->state->mode = ZBAD; |
| 2873 | z->msg = "invalid reserved bit"; |
| 2874 | z->state->sub.marker = 5; /* can't try inflateSync */ |
| 2875 | break; |
| 2876 | } |
| 2877 | if (((z->state->sub.method << 8) + b) % 31) |
| 2878 | { |
| 2879 | z->state->mode = ZBAD; |
| 2880 | z->msg = "incorrect header check"; |
| 2881 | z->state->sub.marker = 5; /* can't try inflateSync */ |
| 2882 | break; |
| 2883 | } |
| 2884 | Trace((stderr, "inflate: zlib header ok\n")); |
| 2885 | z->state->mode = BLOCKS; |
| 2886 | case BLOCKS: |
| 2887 | r = inflate_blocks(z->state->blocks, z, r); |
| 2888 | if (f == Z_PACKET_FLUSH && z->avail_in == 0 && z->avail_out != 0) |
| 2889 | r = inflate_packet_flush(z->state->blocks); |
| 2890 | if (r == Z_DATA_ERROR) |
| 2891 | { |
| 2892 | z->state->mode = ZBAD; |
| 2893 | z->state->sub.marker = 0; /* can try inflateSync */ |
| 2894 | break; |
| 2895 | } |
| 2896 | if (r != Z_STREAM_END) |
| 2897 | return r; |
| 2898 | r = Z_OK; |
| 2899 | inflate_blocks_reset(z->state->blocks, z, &z->state->sub.check.was); |
| 2900 | if (z->state->nowrap) |
| 2901 | { |
| 2902 | z->state->mode = DONE; |
| 2903 | break; |
| 2904 | } |
| 2905 | z->state->mode = CHECK4; |
| 2906 | case CHECK4: |
| 2907 | NEEDBYTE |
| 2908 | z->state->sub.check.need = (uLong)NEXTBYTE << 24; |
| 2909 | z->state->mode = CHECK3; |
| 2910 | case CHECK3: |
| 2911 | NEEDBYTE |
| 2912 | z->state->sub.check.need += (uLong)NEXTBYTE << 16; |
| 2913 | z->state->mode = CHECK2; |
| 2914 | case CHECK2: |
| 2915 | NEEDBYTE |
| 2916 | z->state->sub.check.need += (uLong)NEXTBYTE << 8; |
| 2917 | z->state->mode = CHECK1; |
| 2918 | case CHECK1: |
| 2919 | NEEDBYTE |
| 2920 | z->state->sub.check.need += (uLong)NEXTBYTE; |
| 2921 | |
| 2922 | if (z->state->sub.check.was != z->state->sub.check.need) |
| 2923 | { |
| 2924 | z->state->mode = ZBAD; |
| 2925 | z->msg = "incorrect data check"; |
| 2926 | z->state->sub.marker = 5; /* can't try inflateSync */ |
| 2927 | break; |
| 2928 | } |
| 2929 | Trace((stderr, "inflate: zlib check ok\n")); |
| 2930 | z->state->mode = DONE; |
| 2931 | case DONE: |
| 2932 | return Z_STREAM_END; |
| 2933 | case ZBAD: |
| 2934 | return Z_DATA_ERROR; |
| 2935 | default: |
| 2936 | return Z_STREAM_ERROR; |
| 2937 | } |
| 2938 | |
| 2939 | empty: |
| 2940 | if (f != Z_PACKET_FLUSH) |
| 2941 | return r; |
| 2942 | z->state->mode = ZBAD; |
| 2943 | z->state->sub.marker = 0; /* can try inflateSync */ |
| 2944 | return Z_DATA_ERROR; |
| 2945 | } |
| 2946 | |
| 2947 | /* |
| 2948 | * This subroutine adds the data at next_in/avail_in to the output history |
| 2949 | * without performing any output. The output buffer must be "caught up"; |
| 2950 | * i.e. no pending output (hence s->read equals s->write), and the state must |
| 2951 | * be BLOCKS (i.e. we should be willing to see the start of a series of |
| 2952 | * BLOCKS). On exit, the output will also be caught up, and the checksum |
| 2953 | * will have been updated if need be. |
| 2954 | */ |
| 2955 | |
| 2956 | int inflateIncomp(z) |
| 2957 | z_stream *z; |
| 2958 | { |
| 2959 | if (z->state->mode != BLOCKS) |
| 2960 | return Z_DATA_ERROR; |
| 2961 | return inflate_addhistory(z->state->blocks, z); |
| 2962 | } |
| 2963 | |
| 2964 | |
| 2965 | int inflateSync(z) |
| 2966 | z_stream *z; |
| 2967 | { |
| 2968 | uInt n; /* number of bytes to look at */ |
| 2969 | Bytef *p; /* pointer to bytes */ |
| 2970 | uInt m; /* number of marker bytes found in a row */ |
| 2971 | uLong r, w; /* temporaries to save total_in and total_out */ |
| 2972 | |
| 2973 | /* set up */ |
| 2974 | if (z == Z_NULL || z->state == Z_NULL) |
| 2975 | return Z_STREAM_ERROR; |
| 2976 | if (z->state->mode != ZBAD) |
| 2977 | { |
| 2978 | z->state->mode = ZBAD; |
| 2979 | z->state->sub.marker = 0; |
| 2980 | } |
| 2981 | if ((n = z->avail_in) == 0) |
| 2982 | return Z_BUF_ERROR; |
| 2983 | p = z->next_in; |
| 2984 | m = z->state->sub.marker; |
| 2985 | |
| 2986 | /* search */ |
| 2987 | while (n && m < 4) |
| 2988 | { |
| 2989 | if (*p == (Byte)(m < 2 ? 0 : 0xff)) |
| 2990 | m++; |
| 2991 | else if (*p) |
| 2992 | m = 0; |
| 2993 | else |
| 2994 | m = 4 - m; |
| 2995 | p++, n--; |
| 2996 | } |
| 2997 | |
| 2998 | /* restore */ |
| 2999 | z->total_in += p - z->next_in; |
| 3000 | z->next_in = p; |
| 3001 | z->avail_in = n; |
| 3002 | z->state->sub.marker = m; |
| 3003 | |
| 3004 | /* return no joy or set up to restart on a new block */ |
| 3005 | if (m != 4) |
| 3006 | return Z_DATA_ERROR; |
| 3007 | r = z->total_in; w = z->total_out; |
| 3008 | inflateReset(z); |
| 3009 | z->total_in = r; z->total_out = w; |
| 3010 | z->state->mode = BLOCKS; |
| 3011 | return Z_OK; |
| 3012 | } |
| 3013 | |
| 3014 | #undef NEEDBYTE |
| 3015 | #undef NEXTBYTE |
| 3016 | |
| 3017 | /*+++++*/ |
| 3018 | /* infutil.h -- types and macros common to blocks and codes |
| 3019 | * Copyright (C) 1995 Mark Adler |
| 3020 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 3021 | */ |
| 3022 | |
| 3023 | /* WARNING: this file should *not* be used by applications. It is |
| 3024 | part of the implementation of the compression library and is |
| 3025 | subject to change. Applications should only use zlib.h. |
| 3026 | */ |
| 3027 | |
| 3028 | /* inflate blocks semi-private state */ |
| 3029 | struct inflate_blocks_state { |
| 3030 | |
| 3031 | /* mode */ |
| 3032 | enum { |
| 3033 | TYPE, /* get type bits (3, including end bit) */ |
| 3034 | LENS, /* get lengths for stored */ |
| 3035 | STORED, /* processing stored block */ |
| 3036 | TABLE, /* get table lengths */ |
| 3037 | BTREE, /* get bit lengths tree for a dynamic block */ |
| 3038 | DTREE, /* get length, distance trees for a dynamic block */ |
| 3039 | CODES, /* processing fixed or dynamic block */ |
| 3040 | DRY, /* output remaining window bytes */ |
| 3041 | DONEB, /* finished last block, done */ |
| 3042 | BADB} /* got a data error--stuck here */ |
| 3043 | mode; /* current inflate_block mode */ |
| 3044 | |
| 3045 | /* mode dependent information */ |
| 3046 | union { |
| 3047 | uInt left; /* if STORED, bytes left to copy */ |
| 3048 | struct { |
| 3049 | uInt table; /* table lengths (14 bits) */ |
| 3050 | uInt index; /* index into blens (or border) */ |
| 3051 | uIntf *blens; /* bit lengths of codes */ |
| 3052 | uInt bb; /* bit length tree depth */ |
| 3053 | inflate_huft *tb; /* bit length decoding tree */ |
| 3054 | int nblens; /* # elements allocated at blens */ |
| 3055 | } trees; /* if DTREE, decoding info for trees */ |
| 3056 | struct { |
| 3057 | inflate_huft *tl, *td; /* trees to free */ |
| 3058 | inflate_codes_statef |
| 3059 | *codes; |
| 3060 | } decode; /* if CODES, current state */ |
| 3061 | } sub; /* submode */ |
| 3062 | uInt last; /* true if this block is the last block */ |
| 3063 | |
| 3064 | /* mode independent information */ |
| 3065 | uInt bitk; /* bits in bit buffer */ |
| 3066 | uLong bitb; /* bit buffer */ |
| 3067 | Bytef *window; /* sliding window */ |
| 3068 | Bytef *end; /* one byte after sliding window */ |
| 3069 | Bytef *read; /* window read pointer */ |
| 3070 | Bytef *write; /* window write pointer */ |
| 3071 | check_func checkfn; /* check function */ |
| 3072 | uLong check; /* check on output */ |
| 3073 | |
| 3074 | }; |
| 3075 | |
| 3076 | |
| 3077 | /* defines for inflate input/output */ |
| 3078 | /* update pointers and return */ |
| 3079 | #define UPDBITS {s->bitb=b;s->bitk=k;} |
| 3080 | #define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;} |
| 3081 | #define UPDOUT {s->write=q;} |
| 3082 | #define UPDATE {UPDBITS UPDIN UPDOUT} |
| 3083 | #define LEAVE {UPDATE return inflate_flush(s,z,r);} |
| 3084 | /* get bytes and bits */ |
| 3085 | #define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;} |
| 3086 | #define NEEDBYTE {if(n)r=Z_OK;else LEAVE} |
| 3087 | #define NEXTBYTE (n--,*p++) |
| 3088 | #define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}} |
| 3089 | #define DUMPBITS(j) {b>>=(j);k-=(j);} |
| 3090 | /* output bytes */ |
| 3091 | #define WAVAIL (q<s->read?s->read-q-1:s->end-q) |
| 3092 | #define LOADOUT {q=s->write;m=WAVAIL;} |
| 3093 | #define ZWRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=WAVAIL;}} |
| 3094 | #define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT} |
| 3095 | #define NEEDOUT {if(m==0){ZWRAP if(m==0){FLUSH ZWRAP if(m==0) LEAVE}}r=Z_OK;} |
| 3096 | #define OUTBYTE(a) {*q++=(Byte)(a);m--;} |
| 3097 | /* load local pointers */ |
| 3098 | #define LOAD {LOADIN LOADOUT} |
| 3099 | |
| 3100 | /* And'ing with mask[n] masks the lower n bits */ |
| 3101 | local uInt inflate_mask[] = { |
| 3102 | 0x0000, |
| 3103 | 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff, |
| 3104 | 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff |
| 3105 | }; |
| 3106 | |
| 3107 | /* copy as much as possible from the sliding window to the output area */ |
| 3108 | local int inflate_flush OF(( |
| 3109 | inflate_blocks_statef *, |
| 3110 | z_stream *, |
| 3111 | int)); |
| 3112 | |
| 3113 | /*+++++*/ |
| 3114 | /* inffast.h -- header to use inffast.c |
| 3115 | * Copyright (C) 1995 Mark Adler |
| 3116 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 3117 | */ |
| 3118 | |
| 3119 | /* WARNING: this file should *not* be used by applications. It is |
| 3120 | part of the implementation of the compression library and is |
| 3121 | subject to change. Applications should only use zlib.h. |
| 3122 | */ |
| 3123 | |
| 3124 | local int inflate_fast OF(( |
| 3125 | uInt, |
| 3126 | uInt, |
| 3127 | inflate_huft *, |
| 3128 | inflate_huft *, |
| 3129 | inflate_blocks_statef *, |
| 3130 | z_stream *)); |
| 3131 | |
| 3132 | |
| 3133 | /*+++++*/ |
| 3134 | /* infblock.c -- interpret and process block types to last block |
| 3135 | * Copyright (C) 1995 Mark Adler |
| 3136 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 3137 | */ |
| 3138 | |
| 3139 | /* Table for deflate from PKZIP's appnote.txt. */ |
| 3140 | local uInt border[] = { /* Order of the bit length code lengths */ |
| 3141 | 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}; |
| 3142 | |
| 3143 | /* |
| 3144 | Notes beyond the 1.93a appnote.txt: |
| 3145 | |
| 3146 | 1. Distance pointers never point before the beginning of the output |
| 3147 | stream. |
| 3148 | 2. Distance pointers can point back across blocks, up to 32k away. |
| 3149 | 3. There is an implied maximum of 7 bits for the bit length table and |
| 3150 | 15 bits for the actual data. |
| 3151 | 4. If only one code exists, then it is encoded using one bit. (Zero |
| 3152 | would be more efficient, but perhaps a little confusing.) If two |
| 3153 | codes exist, they are coded using one bit each (0 and 1). |
| 3154 | 5. There is no way of sending zero distance codes--a dummy must be |
| 3155 | sent if there are none. (History: a pre 2.0 version of PKZIP would |
| 3156 | store blocks with no distance codes, but this was discovered to be |
| 3157 | too harsh a criterion.) Valid only for 1.93a. 2.04c does allow |
| 3158 | zero distance codes, which is sent as one code of zero bits in |
| 3159 | length. |
| 3160 | 6. There are up to 286 literal/length codes. Code 256 represents the |
| 3161 | end-of-block. Note however that the static length tree defines |
| 3162 | 288 codes just to fill out the Huffman codes. Codes 286 and 287 |
| 3163 | cannot be used though, since there is no length base or extra bits |
| 3164 | defined for them. Similarily, there are up to 30 distance codes. |
| 3165 | However, static trees define 32 codes (all 5 bits) to fill out the |
| 3166 | Huffman codes, but the last two had better not show up in the data. |
| 3167 | 7. Unzip can check dynamic Huffman blocks for complete code sets. |
| 3168 | The exception is that a single code would not be complete (see #4). |
| 3169 | 8. The five bits following the block type is really the number of |
| 3170 | literal codes sent minus 257. |
| 3171 | 9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits |
| 3172 | (1+6+6). Therefore, to output three times the length, you output |
| 3173 | three codes (1+1+1), whereas to output four times the same length, |
| 3174 | you only need two codes (1+3). Hmm. |
| 3175 | 10. In the tree reconstruction algorithm, Code = Code + Increment |
| 3176 | only if BitLength(i) is not zero. (Pretty obvious.) |
| 3177 | 11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19) |
| 3178 | 12. Note: length code 284 can represent 227-258, but length code 285 |
| 3179 | really is 258. The last length deserves its own, short code |
| 3180 | since it gets used a lot in very redundant files. The length |
| 3181 | 258 is special since 258 - 3 (the min match length) is 255. |
| 3182 | 13. The literal/length and distance code bit lengths are read as a |
| 3183 | single stream of lengths. It is possible (and advantageous) for |
| 3184 | a repeat code (16, 17, or 18) to go across the boundary between |
| 3185 | the two sets of lengths. |
| 3186 | */ |
| 3187 | |
| 3188 | |
| 3189 | local void inflate_blocks_reset(s, z, c) |
| 3190 | inflate_blocks_statef *s; |
| 3191 | z_stream *z; |
| 3192 | uLongf *c; |
| 3193 | { |
| 3194 | if (s->checkfn != Z_NULL) |
| 3195 | *c = s->check; |
| 3196 | if (s->mode == BTREE || s->mode == DTREE) |
| 3197 | ZFREE(z, s->sub.trees.blens, s->sub.trees.nblens * sizeof(uInt)); |
| 3198 | if (s->mode == CODES) |
| 3199 | { |
| 3200 | inflate_codes_free(s->sub.decode.codes, z); |
| 3201 | inflate_trees_free(s->sub.decode.td, z); |
| 3202 | inflate_trees_free(s->sub.decode.tl, z); |
| 3203 | } |
| 3204 | s->mode = TYPE; |
| 3205 | s->bitk = 0; |
| 3206 | s->bitb = 0; |
| 3207 | s->read = s->write = s->window; |
| 3208 | if (s->checkfn != Z_NULL) |
| 3209 | s->check = (*s->checkfn)(0L, Z_NULL, 0); |
| 3210 | Trace((stderr, "inflate: blocks reset\n")); |
| 3211 | } |
| 3212 | |
| 3213 | |
| 3214 | local inflate_blocks_statef *inflate_blocks_new(z, c, w) |
| 3215 | z_stream *z; |
| 3216 | check_func c; |
| 3217 | uInt w; |
| 3218 | { |
| 3219 | inflate_blocks_statef *s; |
| 3220 | |
| 3221 | if ((s = (inflate_blocks_statef *)ZALLOC |
| 3222 | (z,1,sizeof(struct inflate_blocks_state))) == Z_NULL) |
| 3223 | return s; |
| 3224 | if ((s->window = (Bytef *)ZALLOC(z, 1, w)) == Z_NULL) |
| 3225 | { |
| 3226 | ZFREE(z, s, sizeof(struct inflate_blocks_state)); |
| 3227 | return Z_NULL; |
| 3228 | } |
| 3229 | s->end = s->window + w; |
| 3230 | s->checkfn = c; |
| 3231 | s->mode = TYPE; |
| 3232 | Trace((stderr, "inflate: blocks allocated\n")); |
| 3233 | inflate_blocks_reset(s, z, &s->check); |
| 3234 | return s; |
| 3235 | } |
| 3236 | |
| 3237 | |
| 3238 | local int inflate_blocks(s, z, r) |
| 3239 | inflate_blocks_statef *s; |
| 3240 | z_stream *z; |
| 3241 | int r; |
| 3242 | { |
| 3243 | uInt t; /* temporary storage */ |
| 3244 | uLong b; /* bit buffer */ |
| 3245 | uInt k; /* bits in bit buffer */ |
| 3246 | Bytef *p; /* input data pointer */ |
| 3247 | uInt n; /* bytes available there */ |
| 3248 | Bytef *q; /* output window write pointer */ |
| 3249 | uInt m; /* bytes to end of window or read pointer */ |
| 3250 | |
| 3251 | /* copy input/output information to locals (UPDATE macro restores) */ |
| 3252 | LOAD |
| 3253 | |
| 3254 | /* process input based on current state */ |
| 3255 | while (1) switch (s->mode) |
| 3256 | { |
| 3257 | case TYPE: |
| 3258 | NEEDBITS(3) |
| 3259 | t = (uInt)b & 7; |
| 3260 | s->last = t & 1; |
| 3261 | switch (t >> 1) |
| 3262 | { |
| 3263 | case 0: /* stored */ |
| 3264 | Trace((stderr, "inflate: stored block%s\n", |
| 3265 | s->last ? " (last)" : "")); |
| 3266 | DUMPBITS(3) |
| 3267 | t = k & 7; /* go to byte boundary */ |
| 3268 | DUMPBITS(t) |
| 3269 | s->mode = LENS; /* get length of stored block */ |
| 3270 | break; |
| 3271 | case 1: /* fixed */ |
| 3272 | Trace((stderr, "inflate: fixed codes block%s\n", |
| 3273 | s->last ? " (last)" : "")); |
| 3274 | { |
| 3275 | uInt bl, bd; |
| 3276 | inflate_huft *tl, *td; |
| 3277 | |
| 3278 | inflate_trees_fixed(&bl, &bd, &tl, &td); |
| 3279 | s->sub.decode.codes = inflate_codes_new(bl, bd, tl, td, z); |
| 3280 | if (s->sub.decode.codes == Z_NULL) |
| 3281 | { |
| 3282 | r = Z_MEM_ERROR; |
| 3283 | LEAVE |
| 3284 | } |
| 3285 | s->sub.decode.tl = Z_NULL; /* don't try to free these */ |
| 3286 | s->sub.decode.td = Z_NULL; |
| 3287 | } |
| 3288 | DUMPBITS(3) |
| 3289 | s->mode = CODES; |
| 3290 | break; |
| 3291 | case 2: /* dynamic */ |
| 3292 | Trace((stderr, "inflate: dynamic codes block%s\n", |
| 3293 | s->last ? " (last)" : "")); |
| 3294 | DUMPBITS(3) |
| 3295 | s->mode = TABLE; |
| 3296 | break; |
| 3297 | case 3: /* illegal */ |
| 3298 | DUMPBITS(3) |
| 3299 | s->mode = BADB; |
| 3300 | z->msg = "invalid block type"; |
| 3301 | r = Z_DATA_ERROR; |
| 3302 | LEAVE |
| 3303 | } |
| 3304 | break; |
| 3305 | case LENS: |
| 3306 | NEEDBITS(32) |
| 3307 | if (((~b) >> 16) != (b & 0xffff)) |
| 3308 | { |
| 3309 | s->mode = BADB; |
| 3310 | z->msg = "invalid stored block lengths"; |
| 3311 | r = Z_DATA_ERROR; |
| 3312 | LEAVE |
| 3313 | } |
| 3314 | s->sub.left = (uInt)b & 0xffff; |
| 3315 | b = k = 0; /* dump bits */ |
| 3316 | Tracev((stderr, "inflate: stored length %u\n", s->sub.left)); |
| 3317 | s->mode = s->sub.left ? STORED : TYPE; |
| 3318 | break; |
| 3319 | case STORED: |
| 3320 | if (n == 0) |
| 3321 | LEAVE |
| 3322 | NEEDOUT |
| 3323 | t = s->sub.left; |
| 3324 | if (t > n) t = n; |
| 3325 | if (t > m) t = m; |
| 3326 | zmemcpy(q, p, t); |
| 3327 | p += t; n -= t; |
| 3328 | q += t; m -= t; |
| 3329 | if ((s->sub.left -= t) != 0) |
| 3330 | break; |
| 3331 | Tracev((stderr, "inflate: stored end, %lu total out\n", |
| 3332 | z->total_out + (q >= s->read ? q - s->read : |
| 3333 | (s->end - s->read) + (q - s->window)))); |
| 3334 | s->mode = s->last ? DRY : TYPE; |
| 3335 | break; |
| 3336 | case TABLE: |
| 3337 | NEEDBITS(14) |
| 3338 | s->sub.trees.table = t = (uInt)b & 0x3fff; |
| 3339 | #ifndef PKZIP_BUG_WORKAROUND |
| 3340 | if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29) |
| 3341 | { |
| 3342 | s->mode = BADB; |
| 3343 | z->msg = "too many length or distance symbols"; |
| 3344 | r = Z_DATA_ERROR; |
| 3345 | LEAVE |
| 3346 | } |
| 3347 | #endif |
| 3348 | t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f); |
| 3349 | if (t < 19) |
| 3350 | t = 19; |
| 3351 | if ((s->sub.trees.blens = (uIntf*)ZALLOC(z, t, sizeof(uInt))) == Z_NULL) |
| 3352 | { |
| 3353 | r = Z_MEM_ERROR; |
| 3354 | LEAVE |
| 3355 | } |
| 3356 | s->sub.trees.nblens = t; |
| 3357 | DUMPBITS(14) |
| 3358 | s->sub.trees.index = 0; |
| 3359 | Tracev((stderr, "inflate: table sizes ok\n")); |
| 3360 | s->mode = BTREE; |
| 3361 | case BTREE: |
| 3362 | while (s->sub.trees.index < 4 + (s->sub.trees.table >> 10)) |
| 3363 | { |
| 3364 | NEEDBITS(3) |
| 3365 | s->sub.trees.blens[border[s->sub.trees.index++]] = (uInt)b & 7; |
| 3366 | DUMPBITS(3) |
| 3367 | } |
| 3368 | while (s->sub.trees.index < 19) |
| 3369 | s->sub.trees.blens[border[s->sub.trees.index++]] = 0; |
| 3370 | s->sub.trees.bb = 7; |
| 3371 | t = inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb, |
| 3372 | &s->sub.trees.tb, z); |
| 3373 | if (t != Z_OK) |
| 3374 | { |
| 3375 | r = t; |
| 3376 | if (r == Z_DATA_ERROR) |
| 3377 | s->mode = BADB; |
| 3378 | LEAVE |
| 3379 | } |
| 3380 | s->sub.trees.index = 0; |
| 3381 | Tracev((stderr, "inflate: bits tree ok\n")); |
| 3382 | s->mode = DTREE; |
| 3383 | case DTREE: |
| 3384 | while (t = s->sub.trees.table, |
| 3385 | s->sub.trees.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f)) |
| 3386 | { |
| 3387 | inflate_huft *h; |
| 3388 | uInt i, j, c; |
| 3389 | |
| 3390 | t = s->sub.trees.bb; |
| 3391 | NEEDBITS(t) |
| 3392 | h = s->sub.trees.tb + ((uInt)b & inflate_mask[t]); |
| 3393 | t = h->word.what.Bits; |
| 3394 | c = h->more.Base; |
| 3395 | if (c < 16) |
| 3396 | { |
| 3397 | DUMPBITS(t) |
| 3398 | s->sub.trees.blens[s->sub.trees.index++] = c; |
| 3399 | } |
| 3400 | else /* c == 16..18 */ |
| 3401 | { |
| 3402 | i = c == 18 ? 7 : c - 14; |
| 3403 | j = c == 18 ? 11 : 3; |
| 3404 | NEEDBITS(t + i) |
| 3405 | DUMPBITS(t) |
| 3406 | j += (uInt)b & inflate_mask[i]; |
| 3407 | DUMPBITS(i) |
| 3408 | i = s->sub.trees.index; |
| 3409 | t = s->sub.trees.table; |
| 3410 | if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) || |
| 3411 | (c == 16 && i < 1)) |
| 3412 | { |
| 3413 | s->mode = BADB; |
| 3414 | z->msg = "invalid bit length repeat"; |
| 3415 | r = Z_DATA_ERROR; |
| 3416 | LEAVE |
| 3417 | } |
| 3418 | c = c == 16 ? s->sub.trees.blens[i - 1] : 0; |
| 3419 | do { |
| 3420 | s->sub.trees.blens[i++] = c; |
| 3421 | } while (--j); |
| 3422 | s->sub.trees.index = i; |
| 3423 | } |
| 3424 | } |
| 3425 | inflate_trees_free(s->sub.trees.tb, z); |
| 3426 | s->sub.trees.tb = Z_NULL; |
| 3427 | { |
| 3428 | uInt bl, bd; |
| 3429 | inflate_huft *tl, *td; |
| 3430 | inflate_codes_statef *c; |
| 3431 | |
| 3432 | bl = 9; /* must be <= 9 for lookahead assumptions */ |
| 3433 | bd = 6; /* must be <= 9 for lookahead assumptions */ |
| 3434 | t = s->sub.trees.table; |
| 3435 | t = inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f), |
| 3436 | s->sub.trees.blens, &bl, &bd, &tl, &td, z); |
| 3437 | if (t != Z_OK) |
| 3438 | { |
| 3439 | if (t == (uInt)Z_DATA_ERROR) |
| 3440 | s->mode = BADB; |
| 3441 | r = t; |
| 3442 | LEAVE |
| 3443 | } |
| 3444 | Tracev((stderr, "inflate: trees ok\n")); |
| 3445 | if ((c = inflate_codes_new(bl, bd, tl, td, z)) == Z_NULL) |
| 3446 | { |
| 3447 | inflate_trees_free(td, z); |
| 3448 | inflate_trees_free(tl, z); |
| 3449 | r = Z_MEM_ERROR; |
| 3450 | LEAVE |
| 3451 | } |
| 3452 | ZFREE(z, s->sub.trees.blens, s->sub.trees.nblens * sizeof(uInt)); |
| 3453 | s->sub.decode.codes = c; |
| 3454 | s->sub.decode.tl = tl; |
| 3455 | s->sub.decode.td = td; |
| 3456 | } |
| 3457 | s->mode = CODES; |
| 3458 | case CODES: |
| 3459 | UPDATE |
| 3460 | if ((r = inflate_codes(s, z, r)) != Z_STREAM_END) |
| 3461 | return inflate_flush(s, z, r); |
| 3462 | r = Z_OK; |
| 3463 | inflate_codes_free(s->sub.decode.codes, z); |
| 3464 | inflate_trees_free(s->sub.decode.td, z); |
| 3465 | inflate_trees_free(s->sub.decode.tl, z); |
| 3466 | LOAD |
| 3467 | Tracev((stderr, "inflate: codes end, %lu total out\n", |
| 3468 | z->total_out + (q >= s->read ? q - s->read : |
| 3469 | (s->end - s->read) + (q - s->window)))); |
| 3470 | if (!s->last) |
| 3471 | { |
| 3472 | s->mode = TYPE; |
| 3473 | break; |
| 3474 | } |
| 3475 | if (k > 7) /* return unused byte, if any */ |
| 3476 | { |
| 3477 | Assert(k < 16, "inflate_codes grabbed too many bytes") |
| 3478 | k -= 8; |
| 3479 | n++; |
| 3480 | p--; /* can always return one */ |
| 3481 | } |
| 3482 | s->mode = DRY; |
| 3483 | case DRY: |
| 3484 | FLUSH |
| 3485 | if (s->read != s->write) |
| 3486 | LEAVE |
| 3487 | s->mode = DONEB; |
| 3488 | case DONEB: |
| 3489 | r = Z_STREAM_END; |
| 3490 | LEAVE |
| 3491 | case BADB: |
| 3492 | r = Z_DATA_ERROR; |
| 3493 | LEAVE |
| 3494 | default: |
| 3495 | r = Z_STREAM_ERROR; |
| 3496 | LEAVE |
| 3497 | } |
| 3498 | } |
| 3499 | |
| 3500 | |
| 3501 | local int inflate_blocks_free(s, z, c) |
| 3502 | inflate_blocks_statef *s; |
| 3503 | z_stream *z; |
| 3504 | uLongf *c; |
| 3505 | { |
| 3506 | inflate_blocks_reset(s, z, c); |
| 3507 | ZFREE(z, s->window, s->end - s->window); |
| 3508 | ZFREE(z, s, sizeof(struct inflate_blocks_state)); |
| 3509 | Trace((stderr, "inflate: blocks freed\n")); |
| 3510 | return Z_OK; |
| 3511 | } |
| 3512 | |
| 3513 | /* |
| 3514 | * This subroutine adds the data at next_in/avail_in to the output history |
| 3515 | * without performing any output. The output buffer must be "caught up"; |
| 3516 | * i.e. no pending output (hence s->read equals s->write), and the state must |
| 3517 | * be BLOCKS (i.e. we should be willing to see the start of a series of |
| 3518 | * BLOCKS). On exit, the output will also be caught up, and the checksum |
| 3519 | * will have been updated if need be. |
| 3520 | */ |
| 3521 | local int inflate_addhistory(s, z) |
| 3522 | inflate_blocks_statef *s; |
| 3523 | z_stream *z; |
| 3524 | { |
| 3525 | uLong b; /* bit buffer */ /* NOT USED HERE */ |
| 3526 | uInt k; /* bits in bit buffer */ /* NOT USED HERE */ |
| 3527 | uInt t; /* temporary storage */ |
| 3528 | Bytef *p; /* input data pointer */ |
| 3529 | uInt n; /* bytes available there */ |
| 3530 | Bytef *q; /* output window write pointer */ |
| 3531 | uInt m; /* bytes to end of window or read pointer */ |
| 3532 | |
| 3533 | if (s->read != s->write) |
| 3534 | return Z_STREAM_ERROR; |
| 3535 | if (s->mode != TYPE) |
| 3536 | return Z_DATA_ERROR; |
| 3537 | |
| 3538 | /* we're ready to rock */ |
| 3539 | LOAD |
| 3540 | /* while there is input ready, copy to output buffer, moving |
| 3541 | * pointers as needed. |
| 3542 | */ |
| 3543 | while (n) { |
| 3544 | t = n; /* how many to do */ |
| 3545 | /* is there room until end of buffer? */ |
| 3546 | if (t > m) t = m; |
| 3547 | /* update check information */ |
| 3548 | if (s->checkfn != Z_NULL) |
| 3549 | s->check = (*s->checkfn)(s->check, q, t); |
| 3550 | zmemcpy(q, p, t); |
| 3551 | q += t; |
| 3552 | p += t; |
| 3553 | n -= t; |
| 3554 | z->total_out += t; |
| 3555 | s->read = q; /* drag read pointer forward */ |
| 3556 | /* ZWRAP */ /* expand ZWRAP macro by hand to handle s->read */ |
| 3557 | if (q == s->end) { |
| 3558 | s->read = q = s->window; |
| 3559 | m = WAVAIL; |
| 3560 | } |
| 3561 | } |
| 3562 | UPDATE |
| 3563 | return Z_OK; |
| 3564 | } |
| 3565 | |
| 3566 | |
| 3567 | /* |
| 3568 | * At the end of a Deflate-compressed PPP packet, we expect to have seen |
| 3569 | * a `stored' block type value but not the (zero) length bytes. |
| 3570 | */ |
| 3571 | local int inflate_packet_flush(s) |
| 3572 | inflate_blocks_statef *s; |
| 3573 | { |
| 3574 | if (s->mode != LENS) |
| 3575 | return Z_DATA_ERROR; |
| 3576 | s->mode = TYPE; |
| 3577 | return Z_OK; |
| 3578 | } |
| 3579 | |
| 3580 | |
| 3581 | /*+++++*/ |
| 3582 | /* inftrees.c -- generate Huffman trees for efficient decoding |
| 3583 | * Copyright (C) 1995 Mark Adler |
| 3584 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 3585 | */ |
| 3586 | |
| 3587 | /* simplify the use of the inflate_huft type with some defines */ |
| 3588 | #define base more.Base |
| 3589 | #define next more.Next |
| 3590 | #define exop word.what.Exop |
| 3591 | #define bits word.what.Bits |
| 3592 | |
| 3593 | |
| 3594 | local int huft_build OF(( |
| 3595 | uIntf *, /* code lengths in bits */ |
| 3596 | uInt, /* number of codes */ |
| 3597 | uInt, /* number of "simple" codes */ |
| 3598 | uIntf *, /* list of base values for non-simple codes */ |
| 3599 | uIntf *, /* list of extra bits for non-simple codes */ |
| 3600 | inflate_huft * FAR*,/* result: starting table */ |
| 3601 | uIntf *, /* maximum lookup bits (returns actual) */ |
| 3602 | z_stream *)); /* for zalloc function */ |
| 3603 | |
| 3604 | local voidpf falloc OF(( |
| 3605 | voidpf, /* opaque pointer (not used) */ |
| 3606 | uInt, /* number of items */ |
| 3607 | uInt)); /* size of item */ |
| 3608 | |
| 3609 | local void ffree OF(( |
| 3610 | voidpf q, /* opaque pointer (not used) */ |
| 3611 | voidpf p, /* what to free (not used) */ |
| 3612 | uInt n)); /* number of bytes (not used) */ |
| 3613 | |
| 3614 | /* Tables for deflate from PKZIP's appnote.txt. */ |
| 3615 | local uInt cplens[] = { /* Copy lengths for literal codes 257..285 */ |
| 3616 | 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31, |
| 3617 | 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0}; |
| 3618 | /* actually lengths - 2; also see note #13 above about 258 */ |
| 3619 | local uInt cplext[] = { /* Extra bits for literal codes 257..285 */ |
| 3620 | 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, |
| 3621 | 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 192, 192}; /* 192==invalid */ |
| 3622 | local uInt cpdist[] = { /* Copy offsets for distance codes 0..29 */ |
| 3623 | 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193, |
| 3624 | 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145, |
| 3625 | 8193, 12289, 16385, 24577}; |
| 3626 | local uInt cpdext[] = { /* Extra bits for distance codes */ |
| 3627 | 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, |
| 3628 | 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, |
| 3629 | 12, 12, 13, 13}; |
| 3630 | |
| 3631 | /* |
| 3632 | Huffman code decoding is performed using a multi-level table lookup. |
| 3633 | The fastest way to decode is to simply build a lookup table whose |
| 3634 | size is determined by the longest code. However, the time it takes |
| 3635 | to build this table can also be a factor if the data being decoded |
| 3636 | is not very long. The most common codes are necessarily the |
| 3637 | shortest codes, so those codes dominate the decoding time, and hence |
| 3638 | the speed. The idea is you can have a shorter table that decodes the |
| 3639 | shorter, more probable codes, and then point to subsidiary tables for |
| 3640 | the longer codes. The time it costs to decode the longer codes is |
| 3641 | then traded against the time it takes to make longer tables. |
| 3642 | |
| 3643 | This results of this trade are in the variables lbits and dbits |
| 3644 | below. lbits is the number of bits the first level table for literal/ |
| 3645 | length codes can decode in one step, and dbits is the same thing for |
| 3646 | the distance codes. Subsequent tables are also less than or equal to |
| 3647 | those sizes. These values may be adjusted either when all of the |
| 3648 | codes are shorter than that, in which case the longest code length in |
| 3649 | bits is used, or when the shortest code is *longer* than the requested |
| 3650 | table size, in which case the length of the shortest code in bits is |
| 3651 | used. |
| 3652 | |
| 3653 | There are two different values for the two tables, since they code a |
| 3654 | different number of possibilities each. The literal/length table |
| 3655 | codes 286 possible values, or in a flat code, a little over eight |
| 3656 | bits. The distance table codes 30 possible values, or a little less |
| 3657 | than five bits, flat. The optimum values for speed end up being |
| 3658 | about one bit more than those, so lbits is 8+1 and dbits is 5+1. |
| 3659 | The optimum values may differ though from machine to machine, and |
| 3660 | possibly even between compilers. Your mileage may vary. |
| 3661 | */ |
| 3662 | |
| 3663 | |
| 3664 | /* If BMAX needs to be larger than 16, then h and x[] should be uLong. */ |
| 3665 | #define BMAX 15 /* maximum bit length of any code */ |
| 3666 | #define N_MAX 288 /* maximum number of codes in any set */ |
| 3667 | |
| 3668 | #ifdef DEBUG_ZLIB |
| 3669 | uInt inflate_hufts; |
| 3670 | #endif |
| 3671 | |
| 3672 | local int huft_build(b, n, s, d, e, t, m, zs) |
| 3673 | uIntf *b; /* code lengths in bits (all assumed <= BMAX) */ |
| 3674 | uInt n; /* number of codes (assumed <= N_MAX) */ |
| 3675 | uInt s; /* number of simple-valued codes (0..s-1) */ |
| 3676 | uIntf *d; /* list of base values for non-simple codes */ |
| 3677 | uIntf *e; /* list of extra bits for non-simple codes */ |
| 3678 | inflate_huft * FAR *t; /* result: starting table */ |
| 3679 | uIntf *m; /* maximum lookup bits, returns actual */ |
| 3680 | z_stream *zs; /* for zalloc function */ |
| 3681 | /* Given a list of code lengths and a maximum table size, make a set of |
| 3682 | tables to decode that set of codes. Return Z_OK on success, Z_BUF_ERROR |
| 3683 | if the given code set is incomplete (the tables are still built in this |
| 3684 | case), Z_DATA_ERROR if the input is invalid (all zero length codes or an |
| 3685 | over-subscribed set of lengths), or Z_MEM_ERROR if not enough memory. */ |
| 3686 | { |
| 3687 | |
| 3688 | uInt a; /* counter for codes of length k */ |
| 3689 | uInt c[BMAX+1]; /* bit length count table */ |
| 3690 | uInt f; /* i repeats in table every f entries */ |
| 3691 | int g; /* maximum code length */ |
| 3692 | int h; /* table level */ |
| 3693 | register uInt i; /* counter, current code */ |
| 3694 | register uInt j; /* counter */ |
| 3695 | register int k; /* number of bits in current code */ |
| 3696 | int l; /* bits per table (returned in m) */ |
| 3697 | register uIntf *p; /* pointer into c[], b[], or v[] */ |
| 3698 | inflate_huft *q; /* points to current table */ |
| 3699 | struct inflate_huft_s r; /* table entry for structure assignment */ |
| 3700 | inflate_huft *u[BMAX]; /* table stack */ |
| 3701 | uInt v[N_MAX]; /* values in order of bit length */ |
| 3702 | register int w; /* bits before this table == (l * h) */ |
| 3703 | uInt x[BMAX+1]; /* bit offsets, then code stack */ |
| 3704 | uIntf *xp; /* pointer into x */ |
| 3705 | int y; /* number of dummy codes added */ |
| 3706 | uInt z; /* number of entries in current table */ |
| 3707 | |
| 3708 | |
| 3709 | /* Generate counts for each bit length */ |
| 3710 | p = c; |
| 3711 | #define C0 *p++ = 0; |
| 3712 | #define C2 C0 C0 C0 C0 |
| 3713 | #define C4 C2 C2 C2 C2 |
| 3714 | C4 /* clear c[]--assume BMAX+1 is 16 */ |
| 3715 | p = b; i = n; |
| 3716 | do { |
| 3717 | c[*p++]++; /* assume all entries <= BMAX */ |
| 3718 | } while (--i); |
| 3719 | if (c[0] == n) /* null input--all zero length codes */ |
| 3720 | { |
| 3721 | *t = (inflate_huft *)Z_NULL; |
| 3722 | *m = 0; |
| 3723 | return Z_OK; |
| 3724 | } |
| 3725 | |
| 3726 | |
| 3727 | /* Find minimum and maximum length, bound *m by those */ |
| 3728 | l = *m; |
| 3729 | for (j = 1; j <= BMAX; j++) |
| 3730 | if (c[j]) |
| 3731 | break; |
| 3732 | k = j; /* minimum code length */ |
| 3733 | if ((uInt)l < j) |
| 3734 | l = j; |
| 3735 | for (i = BMAX; i; i--) |
| 3736 | if (c[i]) |
| 3737 | break; |
| 3738 | g = i; /* maximum code length */ |
| 3739 | if ((uInt)l > i) |
| 3740 | l = i; |
| 3741 | *m = l; |
| 3742 | |
| 3743 | |
| 3744 | /* Adjust last length count to fill out codes, if needed */ |
| 3745 | for (y = 1 << j; j < i; j++, y <<= 1) |
| 3746 | if ((y -= c[j]) < 0) |
| 3747 | return Z_DATA_ERROR; |
| 3748 | if ((y -= c[i]) < 0) |
| 3749 | return Z_DATA_ERROR; |
| 3750 | c[i] += y; |
| 3751 | |
| 3752 | |
| 3753 | /* Generate starting offsets into the value table for each length */ |
| 3754 | x[1] = j = 0; |
| 3755 | p = c + 1; xp = x + 2; |
| 3756 | while (--i) { /* note that i == g from above */ |
| 3757 | *xp++ = (j += *p++); |
| 3758 | } |
| 3759 | |
| 3760 | |
| 3761 | /* Make a table of values in order of bit lengths */ |
| 3762 | p = b; i = 0; |
| 3763 | do { |
| 3764 | if ((j = *p++) != 0) |
| 3765 | v[x[j]++] = i; |
| 3766 | } while (++i < n); |
| 3767 | |
| 3768 | |
| 3769 | /* Generate the Huffman codes and for each, make the table entries */ |
| 3770 | x[0] = i = 0; /* first Huffman code is zero */ |
| 3771 | p = v; /* grab values in bit order */ |
| 3772 | h = -1; /* no tables yet--level -1 */ |
| 3773 | w = -l; /* bits decoded == (l * h) */ |
| 3774 | u[0] = (inflate_huft *)Z_NULL; /* just to keep compilers happy */ |
| 3775 | q = (inflate_huft *)Z_NULL; /* ditto */ |
| 3776 | z = 0; /* ditto */ |
| 3777 | |
| 3778 | /* go through the bit lengths (k already is bits in shortest code) */ |
| 3779 | for (; k <= g; k++) |
| 3780 | { |
| 3781 | a = c[k]; |
| 3782 | while (a--) |
| 3783 | { |
| 3784 | /* here i is the Huffman code of length k bits for value *p */ |
| 3785 | /* make tables up to required level */ |
| 3786 | while (k > w + l) |
| 3787 | { |
| 3788 | h++; |
| 3789 | w += l; /* previous table always l bits */ |
| 3790 | |
| 3791 | /* compute minimum size table less than or equal to l bits */ |
| 3792 | z = (z = g - w) > (uInt)l ? l : z; /* table size upper limit */ |
| 3793 | if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */ |
| 3794 | { /* too few codes for k-w bit table */ |
| 3795 | f -= a + 1; /* deduct codes from patterns left */ |
| 3796 | xp = c + k; |
| 3797 | if (j < z) |
| 3798 | while (++j < z) /* try smaller tables up to z bits */ |
| 3799 | { |
| 3800 | if ((f <<= 1) <= *++xp) |
| 3801 | break; /* enough codes to use up j bits */ |
| 3802 | f -= *xp; /* else deduct codes from patterns */ |
| 3803 | } |
| 3804 | } |
| 3805 | z = 1 << j; /* table entries for j-bit table */ |
| 3806 | |
| 3807 | /* allocate and link in new table */ |
| 3808 | if ((q = (inflate_huft *)ZALLOC |
| 3809 | (zs,z + 1,sizeof(inflate_huft))) == Z_NULL) |
| 3810 | { |
| 3811 | if (h) |
| 3812 | inflate_trees_free(u[0], zs); |
| 3813 | return Z_MEM_ERROR; /* not enough memory */ |
| 3814 | } |
| 3815 | q->word.Nalloc = z + 1; |
| 3816 | #ifdef DEBUG_ZLIB |
| 3817 | inflate_hufts += z + 1; |
| 3818 | #endif |
| 3819 | *t = q + 1; /* link to list for huft_free() */ |
| 3820 | *(t = &(q->next)) = Z_NULL; |
| 3821 | u[h] = ++q; /* table starts after link */ |
| 3822 | |
| 3823 | /* connect to last table, if there is one */ |
| 3824 | if (h) |
| 3825 | { |
| 3826 | x[h] = i; /* save pattern for backing up */ |
| 3827 | r.bits = (Byte)l; /* bits to dump before this table */ |
| 3828 | r.exop = (Byte)j; /* bits in this table */ |
| 3829 | r.next = q; /* pointer to this table */ |
| 3830 | j = i >> (w - l); /* (get around Turbo C bug) */ |
| 3831 | u[h-1][j] = r; /* connect to last table */ |
| 3832 | } |
| 3833 | } |
| 3834 | |
| 3835 | /* set up table entry in r */ |
| 3836 | r.bits = (Byte)(k - w); |
| 3837 | if (p >= v + n) |
| 3838 | r.exop = 128 + 64; /* out of values--invalid code */ |
| 3839 | else if (*p < s) |
| 3840 | { |
| 3841 | r.exop = (Byte)(*p < 256 ? 0 : 32 + 64); /* 256 is end-of-block */ |
| 3842 | r.base = *p++; /* simple code is just the value */ |
| 3843 | } |
| 3844 | else |
| 3845 | { |
| 3846 | r.exop = (Byte)e[*p - s] + 16 + 64; /* non-simple--look up in lists */ |
| 3847 | r.base = d[*p++ - s]; |
| 3848 | } |
| 3849 | |
| 3850 | /* fill code-like entries with r */ |
| 3851 | f = 1 << (k - w); |
| 3852 | for (j = i >> w; j < z; j += f) |
| 3853 | q[j] = r; |
| 3854 | |
| 3855 | /* backwards increment the k-bit code i */ |
| 3856 | for (j = 1 << (k - 1); i & j; j >>= 1) |
| 3857 | i ^= j; |
| 3858 | i ^= j; |
| 3859 | |
| 3860 | /* backup over finished tables */ |
| 3861 | while ((i & ((1 << w) - 1)) != x[h]) |
| 3862 | { |
| 3863 | h--; /* don't need to update q */ |
| 3864 | w -= l; |
| 3865 | } |
| 3866 | } |
| 3867 | } |
| 3868 | |
| 3869 | |
| 3870 | /* Return Z_BUF_ERROR if we were given an incomplete table */ |
| 3871 | return y != 0 && g != 1 ? Z_BUF_ERROR : Z_OK; |
| 3872 | } |
| 3873 | |
| 3874 | |
| 3875 | local int inflate_trees_bits(c, bb, tb, z) |
| 3876 | uIntf *c; /* 19 code lengths */ |
| 3877 | uIntf *bb; /* bits tree desired/actual depth */ |
| 3878 | inflate_huft * FAR *tb; /* bits tree result */ |
| 3879 | z_stream *z; /* for zfree function */ |
| 3880 | { |
| 3881 | int r; |
| 3882 | |
| 3883 | r = huft_build(c, 19, 19, (uIntf*)Z_NULL, (uIntf*)Z_NULL, tb, bb, z); |
| 3884 | if (r == Z_DATA_ERROR) |
| 3885 | z->msg = "oversubscribed dynamic bit lengths tree"; |
| 3886 | else if (r == Z_BUF_ERROR) |
| 3887 | { |
| 3888 | inflate_trees_free(*tb, z); |
| 3889 | z->msg = "incomplete dynamic bit lengths tree"; |
| 3890 | r = Z_DATA_ERROR; |
| 3891 | } |
| 3892 | return r; |
| 3893 | } |
| 3894 | |
| 3895 | |
| 3896 | local int inflate_trees_dynamic(nl, nd, c, bl, bd, tl, td, z) |
| 3897 | uInt nl; /* number of literal/length codes */ |
| 3898 | uInt nd; /* number of distance codes */ |
| 3899 | uIntf *c; /* that many (total) code lengths */ |
| 3900 | uIntf *bl; /* literal desired/actual bit depth */ |
| 3901 | uIntf *bd; /* distance desired/actual bit depth */ |
| 3902 | inflate_huft * FAR *tl; /* literal/length tree result */ |
| 3903 | inflate_huft * FAR *td; /* distance tree result */ |
| 3904 | z_stream *z; /* for zfree function */ |
| 3905 | { |
| 3906 | int r; |
| 3907 | |
| 3908 | /* build literal/length tree */ |
| 3909 | if ((r = huft_build(c, nl, 257, cplens, cplext, tl, bl, z)) != Z_OK) |
| 3910 | { |
| 3911 | if (r == Z_DATA_ERROR) |
| 3912 | z->msg = "oversubscribed literal/length tree"; |
| 3913 | else if (r == Z_BUF_ERROR) |
| 3914 | { |
| 3915 | inflate_trees_free(*tl, z); |
| 3916 | z->msg = "incomplete literal/length tree"; |
| 3917 | r = Z_DATA_ERROR; |
| 3918 | } |
| 3919 | return r; |
| 3920 | } |
| 3921 | |
| 3922 | /* build distance tree */ |
| 3923 | if ((r = huft_build(c + nl, nd, 0, cpdist, cpdext, td, bd, z)) != Z_OK) |
| 3924 | { |
| 3925 | if (r == Z_DATA_ERROR) |
| 3926 | z->msg = "oversubscribed literal/length tree"; |
| 3927 | else if (r == Z_BUF_ERROR) { |
| 3928 | #ifdef PKZIP_BUG_WORKAROUND |
| 3929 | r = Z_OK; |
| 3930 | } |
| 3931 | #else |
| 3932 | inflate_trees_free(*td, z); |
| 3933 | z->msg = "incomplete literal/length tree"; |
| 3934 | r = Z_DATA_ERROR; |
| 3935 | } |
| 3936 | inflate_trees_free(*tl, z); |
| 3937 | return r; |
| 3938 | #endif |
| 3939 | } |
| 3940 | |
| 3941 | /* done */ |
| 3942 | return Z_OK; |
| 3943 | } |
| 3944 | |
| 3945 | |
| 3946 | /* build fixed tables only once--keep them here */ |
| 3947 | #ifdef MULTI_THREADED |
| 3948 | local volatile int fixed_lock = 0; |
| 3949 | #endif |
| 3950 | local int fixed_built = 0; |
| 3951 | #define FIXEDH 530 /* number of hufts used by fixed tables */ |
| 3952 | local uInt fixed_left = FIXEDH; |
| 3953 | local inflate_huft fixed_mem[FIXEDH]; |
| 3954 | local uInt fixed_bl; |
| 3955 | local uInt fixed_bd; |
| 3956 | local inflate_huft *fixed_tl; |
| 3957 | local inflate_huft *fixed_td; |
| 3958 | |
| 3959 | |
| 3960 | local voidpf falloc(q, n, s) |
| 3961 | voidpf q; /* opaque pointer (not used) */ |
| 3962 | uInt n; /* number of items */ |
| 3963 | uInt s; /* size of item */ |
| 3964 | { |
| 3965 | Assert(s == sizeof(inflate_huft) && n <= fixed_left, |
| 3966 | "inflate_trees falloc overflow"); |
| 3967 | if (q) s++; /* to make some compilers happy */ |
| 3968 | fixed_left -= n; |
| 3969 | return (voidpf)(fixed_mem + fixed_left); |
| 3970 | } |
| 3971 | |
| 3972 | |
| 3973 | local void ffree(q, p, n) |
| 3974 | voidpf q; |
| 3975 | voidpf p; |
| 3976 | uInt n; |
| 3977 | { |
| 3978 | Assert(0, "inflate_trees ffree called!"); |
| 3979 | if (q) q = p; /* to make some compilers happy */ |
| 3980 | } |
| 3981 | |
| 3982 | |
| 3983 | local int inflate_trees_fixed(bl, bd, tl, td) |
| 3984 | uIntf *bl; /* literal desired/actual bit depth */ |
| 3985 | uIntf *bd; /* distance desired/actual bit depth */ |
| 3986 | inflate_huft * FAR *tl; /* literal/length tree result */ |
| 3987 | inflate_huft * FAR *td; /* distance tree result */ |
| 3988 | { |
| 3989 | /* build fixed tables if not built already--lock out other instances */ |
| 3990 | #ifdef MULTI_THREADED |
| 3991 | while (++fixed_lock > 1) |
| 3992 | fixed_lock--; |
| 3993 | #endif |
| 3994 | if (!fixed_built) |
| 3995 | { |
| 3996 | int k; /* temporary variable */ |
| 3997 | unsigned c[288]; /* length list for huft_build */ |
| 3998 | z_stream z; /* for falloc function */ |
| 3999 | |
| 4000 | /* set up fake z_stream for memory routines */ |
| 4001 | z.zalloc = falloc; |
| 4002 | z.zfree = ffree; |
| 4003 | z.opaque = Z_NULL; |
| 4004 | |
| 4005 | /* literal table */ |
| 4006 | for (k = 0; k < 144; k++) |
| 4007 | c[k] = 8; |
| 4008 | for (; k < 256; k++) |
| 4009 | c[k] = 9; |
| 4010 | for (; k < 280; k++) |
| 4011 | c[k] = 7; |
| 4012 | for (; k < 288; k++) |
| 4013 | c[k] = 8; |
| 4014 | fixed_bl = 7; |
| 4015 | huft_build(c, 288, 257, cplens, cplext, &fixed_tl, &fixed_bl, &z); |
| 4016 | |
| 4017 | /* distance table */ |
| 4018 | for (k = 0; k < 30; k++) |
| 4019 | c[k] = 5; |
| 4020 | fixed_bd = 5; |
| 4021 | huft_build(c, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd, &z); |
| 4022 | |
| 4023 | /* done */ |
| 4024 | fixed_built = 1; |
| 4025 | } |
| 4026 | #ifdef MULTI_THREADED |
| 4027 | fixed_lock--; |
| 4028 | #endif |
| 4029 | *bl = fixed_bl; |
| 4030 | *bd = fixed_bd; |
| 4031 | *tl = fixed_tl; |
| 4032 | *td = fixed_td; |
| 4033 | return Z_OK; |
| 4034 | } |
| 4035 | |
| 4036 | |
| 4037 | local int inflate_trees_free(t, z) |
| 4038 | inflate_huft *t; /* table to free */ |
| 4039 | z_stream *z; /* for zfree function */ |
| 4040 | /* Free the malloc'ed tables built by huft_build(), which makes a linked |
| 4041 | list of the tables it made, with the links in a dummy first entry of |
| 4042 | each table. */ |
| 4043 | { |
| 4044 | register inflate_huft *p, *q; |
| 4045 | |
| 4046 | /* Go through linked list, freeing from the malloced (t[-1]) address. */ |
| 4047 | p = t; |
| 4048 | while (p != Z_NULL) |
| 4049 | { |
| 4050 | q = (--p)->next; |
| 4051 | ZFREE(z, p, p->word.Nalloc * sizeof(inflate_huft)); |
| 4052 | p = q; |
| 4053 | } |
| 4054 | return Z_OK; |
| 4055 | } |
| 4056 | |
| 4057 | /*+++++*/ |
| 4058 | /* infcodes.c -- process literals and length/distance pairs |
| 4059 | * Copyright (C) 1995 Mark Adler |
| 4060 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 4061 | */ |
| 4062 | |
| 4063 | /* simplify the use of the inflate_huft type with some defines */ |
| 4064 | #define base more.Base |
| 4065 | #define next more.Next |
| 4066 | #define exop word.what.Exop |
| 4067 | #define bits word.what.Bits |
| 4068 | |
| 4069 | /* inflate codes private state */ |
| 4070 | struct inflate_codes_state { |
| 4071 | |
| 4072 | /* mode */ |
| 4073 | enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */ |
| 4074 | START, /* x: set up for LEN */ |
| 4075 | LEN, /* i: get length/literal/eob next */ |
| 4076 | LENEXT, /* i: getting length extra (have base) */ |
| 4077 | DIST, /* i: get distance next */ |
| 4078 | DISTEXT, /* i: getting distance extra */ |
| 4079 | COPY, /* o: copying bytes in window, waiting for space */ |
| 4080 | LIT, /* o: got literal, waiting for output space */ |
| 4081 | WASH, /* o: got eob, possibly still output waiting */ |
| 4082 | END, /* x: got eob and all data flushed */ |
| 4083 | BADCODE} /* x: got error */ |
| 4084 | mode; /* current inflate_codes mode */ |
| 4085 | |
| 4086 | /* mode dependent information */ |
| 4087 | uInt len; |
| 4088 | union { |
| 4089 | struct { |
| 4090 | inflate_huft *tree; /* pointer into tree */ |
| 4091 | uInt need; /* bits needed */ |
| 4092 | } code; /* if LEN or DIST, where in tree */ |
| 4093 | uInt lit; /* if LIT, literal */ |
| 4094 | struct { |
| 4095 | uInt get; /* bits to get for extra */ |
| 4096 | uInt dist; /* distance back to copy from */ |
| 4097 | } copy; /* if EXT or COPY, where and how much */ |
| 4098 | } sub; /* submode */ |
| 4099 | |
| 4100 | /* mode independent information */ |
| 4101 | Byte lbits; /* ltree bits decoded per branch */ |
| 4102 | Byte dbits; /* dtree bits decoder per branch */ |
| 4103 | inflate_huft *ltree; /* literal/length/eob tree */ |
| 4104 | inflate_huft *dtree; /* distance tree */ |
| 4105 | |
| 4106 | }; |
| 4107 | |
| 4108 | |
| 4109 | local inflate_codes_statef *inflate_codes_new(bl, bd, tl, td, z) |
| 4110 | uInt bl, bd; |
| 4111 | inflate_huft *tl, *td; |
| 4112 | z_stream *z; |
| 4113 | { |
| 4114 | inflate_codes_statef *c; |
| 4115 | |
| 4116 | if ((c = (inflate_codes_statef *) |
| 4117 | ZALLOC(z,1,sizeof(struct inflate_codes_state))) != Z_NULL) |
| 4118 | { |
| 4119 | c->mode = START; |
| 4120 | c->lbits = (Byte)bl; |
| 4121 | c->dbits = (Byte)bd; |
| 4122 | c->ltree = tl; |
| 4123 | c->dtree = td; |
| 4124 | Tracev((stderr, "inflate: codes new\n")); |
| 4125 | } |
| 4126 | return c; |
| 4127 | } |
| 4128 | |
| 4129 | |
| 4130 | local int inflate_codes(s, z, r) |
| 4131 | inflate_blocks_statef *s; |
| 4132 | z_stream *z; |
| 4133 | int r; |
| 4134 | { |
| 4135 | uInt j; /* temporary storage */ |
| 4136 | inflate_huft *t; /* temporary pointer */ |
| 4137 | uInt e; /* extra bits or operation */ |
| 4138 | uLong b; /* bit buffer */ |
| 4139 | uInt k; /* bits in bit buffer */ |
| 4140 | Bytef *p; /* input data pointer */ |
| 4141 | uInt n; /* bytes available there */ |
| 4142 | Bytef *q; /* output window write pointer */ |
| 4143 | uInt m; /* bytes to end of window or read pointer */ |
| 4144 | Bytef *f; /* pointer to copy strings from */ |
| 4145 | inflate_codes_statef *c = s->sub.decode.codes; /* codes state */ |
| 4146 | |
| 4147 | /* copy input/output information to locals (UPDATE macro restores) */ |
| 4148 | LOAD |
| 4149 | |
| 4150 | /* process input and output based on current state */ |
| 4151 | while (1) switch (c->mode) |
| 4152 | { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */ |
| 4153 | case START: /* x: set up for LEN */ |
| 4154 | #ifndef SLOW |
| 4155 | if (m >= 258 && n >= 10) |
| 4156 | { |
| 4157 | UPDATE |
| 4158 | r = inflate_fast(c->lbits, c->dbits, c->ltree, c->dtree, s, z); |
| 4159 | LOAD |
| 4160 | if (r != Z_OK) |
| 4161 | { |
| 4162 | c->mode = r == Z_STREAM_END ? WASH : BADCODE; |
| 4163 | break; |
| 4164 | } |
| 4165 | } |
| 4166 | #endif /* !SLOW */ |
| 4167 | c->sub.code.need = c->lbits; |
| 4168 | c->sub.code.tree = c->ltree; |
| 4169 | c->mode = LEN; |
| 4170 | case LEN: /* i: get length/literal/eob next */ |
| 4171 | j = c->sub.code.need; |
| 4172 | NEEDBITS(j) |
| 4173 | t = c->sub.code.tree + ((uInt)b & inflate_mask[j]); |
| 4174 | DUMPBITS(t->bits) |
| 4175 | e = (uInt)(t->exop); |
| 4176 | if (e == 0) /* literal */ |
| 4177 | { |
| 4178 | c->sub.lit = t->base; |
| 4179 | Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ? |
| 4180 | "inflate: literal '%c'\n" : |
| 4181 | "inflate: literal 0x%02x\n", t->base)); |
| 4182 | c->mode = LIT; |
| 4183 | break; |
| 4184 | } |
| 4185 | if (e & 16) /* length */ |
| 4186 | { |
| 4187 | c->sub.copy.get = e & 15; |
| 4188 | c->len = t->base; |
| 4189 | c->mode = LENEXT; |
| 4190 | break; |
| 4191 | } |
| 4192 | if ((e & 64) == 0) /* next table */ |
| 4193 | { |
| 4194 | c->sub.code.need = e; |
| 4195 | c->sub.code.tree = t->next; |
| 4196 | break; |
| 4197 | } |
| 4198 | if (e & 32) /* end of block */ |
| 4199 | { |
| 4200 | Tracevv((stderr, "inflate: end of block\n")); |
| 4201 | c->mode = WASH; |
| 4202 | break; |
| 4203 | } |
| 4204 | c->mode = BADCODE; /* invalid code */ |
| 4205 | z->msg = "invalid literal/length code"; |
| 4206 | r = Z_DATA_ERROR; |
| 4207 | LEAVE |
| 4208 | case LENEXT: /* i: getting length extra (have base) */ |
| 4209 | j = c->sub.copy.get; |
| 4210 | NEEDBITS(j) |
| 4211 | c->len += (uInt)b & inflate_mask[j]; |
| 4212 | DUMPBITS(j) |
| 4213 | c->sub.code.need = c->dbits; |
| 4214 | c->sub.code.tree = c->dtree; |
| 4215 | Tracevv((stderr, "inflate: length %u\n", c->len)); |
| 4216 | c->mode = DIST; |
| 4217 | case DIST: /* i: get distance next */ |
| 4218 | j = c->sub.code.need; |
| 4219 | NEEDBITS(j) |
| 4220 | t = c->sub.code.tree + ((uInt)b & inflate_mask[j]); |
| 4221 | DUMPBITS(t->bits) |
| 4222 | e = (uInt)(t->exop); |
| 4223 | if (e & 16) /* distance */ |
| 4224 | { |
| 4225 | c->sub.copy.get = e & 15; |
| 4226 | c->sub.copy.dist = t->base; |
| 4227 | c->mode = DISTEXT; |
| 4228 | break; |
| 4229 | } |
| 4230 | if ((e & 64) == 0) /* next table */ |
| 4231 | { |
| 4232 | c->sub.code.need = e; |
| 4233 | c->sub.code.tree = t->next; |
| 4234 | break; |
| 4235 | } |
| 4236 | c->mode = BADCODE; /* invalid code */ |
| 4237 | z->msg = "invalid distance code"; |
| 4238 | r = Z_DATA_ERROR; |
| 4239 | LEAVE |
| 4240 | case DISTEXT: /* i: getting distance extra */ |
| 4241 | j = c->sub.copy.get; |
| 4242 | NEEDBITS(j) |
| 4243 | c->sub.copy.dist += (uInt)b & inflate_mask[j]; |
| 4244 | DUMPBITS(j) |
| 4245 | Tracevv((stderr, "inflate: distance %u\n", c->sub.copy.dist)); |
| 4246 | c->mode = COPY; |
| 4247 | case COPY: /* o: copying bytes in window, waiting for space */ |
| 4248 | #ifndef __TURBOC__ /* Turbo C bug for following expression */ |
| 4249 | f = (uInt)(q - s->window) < c->sub.copy.dist ? |
| 4250 | s->end - (c->sub.copy.dist - (q - s->window)) : |
| 4251 | q - c->sub.copy.dist; |
| 4252 | #else |
| 4253 | f = q - c->sub.copy.dist; |
| 4254 | if ((uInt)(q - s->window) < c->sub.copy.dist) |
| 4255 | f = s->end - (c->sub.copy.dist - (q - s->window)); |
| 4256 | #endif |
| 4257 | while (c->len) |
| 4258 | { |
| 4259 | NEEDOUT |
| 4260 | OUTBYTE(*f++) |
| 4261 | if (f == s->end) |
| 4262 | f = s->window; |
| 4263 | c->len--; |
| 4264 | } |
| 4265 | c->mode = START; |
| 4266 | break; |
| 4267 | case LIT: /* o: got literal, waiting for output space */ |
| 4268 | NEEDOUT |
| 4269 | OUTBYTE(c->sub.lit) |
| 4270 | c->mode = START; |
| 4271 | break; |
| 4272 | case WASH: /* o: got eob, possibly more output */ |
| 4273 | FLUSH |
| 4274 | if (s->read != s->write) |
| 4275 | LEAVE |
| 4276 | c->mode = END; |
| 4277 | case END: |
| 4278 | r = Z_STREAM_END; |
| 4279 | LEAVE |
| 4280 | case BADCODE: /* x: got error */ |
| 4281 | r = Z_DATA_ERROR; |
| 4282 | LEAVE |
| 4283 | default: |
| 4284 | r = Z_STREAM_ERROR; |
| 4285 | LEAVE |
| 4286 | } |
| 4287 | } |
| 4288 | |
| 4289 | |
| 4290 | local void inflate_codes_free(c, z) |
| 4291 | inflate_codes_statef *c; |
| 4292 | z_stream *z; |
| 4293 | { |
| 4294 | ZFREE(z, c, sizeof(struct inflate_codes_state)); |
| 4295 | Tracev((stderr, "inflate: codes free\n")); |
| 4296 | } |
| 4297 | |
| 4298 | /*+++++*/ |
| 4299 | /* inflate_util.c -- data and routines common to blocks and codes |
| 4300 | * Copyright (C) 1995 Mark Adler |
| 4301 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 4302 | */ |
| 4303 | |
| 4304 | /* copy as much as possible from the sliding window to the output area */ |
| 4305 | local int inflate_flush(s, z, r) |
| 4306 | inflate_blocks_statef *s; |
| 4307 | z_stream *z; |
| 4308 | int r; |
| 4309 | { |
| 4310 | uInt n; |
| 4311 | Bytef *p, *q; |
| 4312 | |
| 4313 | /* local copies of source and destination pointers */ |
| 4314 | p = z->next_out; |
| 4315 | q = s->read; |
| 4316 | |
| 4317 | /* compute number of bytes to copy as far as end of window */ |
| 4318 | n = (uInt)((q <= s->write ? s->write : s->end) - q); |
| 4319 | if (n > z->avail_out) n = z->avail_out; |
| 4320 | if (n && r == Z_BUF_ERROR) r = Z_OK; |
| 4321 | |
| 4322 | /* update counters */ |
| 4323 | z->avail_out -= n; |
| 4324 | z->total_out += n; |
| 4325 | |
| 4326 | /* update check information */ |
| 4327 | if (s->checkfn != Z_NULL) |
| 4328 | s->check = (*s->checkfn)(s->check, q, n); |
| 4329 | |
| 4330 | /* copy as far as end of window */ |
| 4331 | if (p != NULL) { |
| 4332 | zmemcpy(p, q, n); |
| 4333 | p += n; |
| 4334 | } |
| 4335 | q += n; |
| 4336 | |
| 4337 | /* see if more to copy at beginning of window */ |
| 4338 | if (q == s->end) |
| 4339 | { |
| 4340 | /* wrap pointers */ |
| 4341 | q = s->window; |
| 4342 | if (s->write == s->end) |
| 4343 | s->write = s->window; |
| 4344 | |
| 4345 | /* compute bytes to copy */ |
| 4346 | n = (uInt)(s->write - q); |
| 4347 | if (n > z->avail_out) n = z->avail_out; |
| 4348 | if (n && r == Z_BUF_ERROR) r = Z_OK; |
| 4349 | |
| 4350 | /* update counters */ |
| 4351 | z->avail_out -= n; |
| 4352 | z->total_out += n; |
| 4353 | |
| 4354 | /* update check information */ |
| 4355 | if (s->checkfn != Z_NULL) |
| 4356 | s->check = (*s->checkfn)(s->check, q, n); |
| 4357 | |
| 4358 | /* copy */ |
| 4359 | if (p != NULL) { |
| 4360 | zmemcpy(p, q, n); |
| 4361 | p += n; |
| 4362 | } |
| 4363 | q += n; |
| 4364 | } |
| 4365 | |
| 4366 | /* update pointers */ |
| 4367 | z->next_out = p; |
| 4368 | s->read = q; |
| 4369 | |
| 4370 | /* done */ |
| 4371 | return r; |
| 4372 | } |
| 4373 | |
| 4374 | |
| 4375 | /*+++++*/ |
| 4376 | /* inffast.c -- process literals and length/distance pairs fast |
| 4377 | * Copyright (C) 1995 Mark Adler |
| 4378 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 4379 | */ |
| 4380 | |
| 4381 | /* simplify the use of the inflate_huft type with some defines */ |
| 4382 | #define base more.Base |
| 4383 | #define next more.Next |
| 4384 | #define exop word.what.Exop |
| 4385 | #define bits word.what.Bits |
| 4386 | |
| 4387 | /* macros for bit input with no checking and for returning unused bytes */ |
| 4388 | #define GRABBITS(j) {while(k<(j)){b|=((uLong)NEXTBYTE)<<k;k+=8;}} |
| 4389 | #define UNGRAB {n+=(c=k>>3);p-=c;k&=7;} |
| 4390 | |
| 4391 | /* Called with number of bytes left to write in window at least 258 |
| 4392 | (the maximum string length) and number of input bytes available |
| 4393 | at least ten. The ten bytes are six bytes for the longest length/ |
| 4394 | distance pair plus four bytes for overloading the bit buffer. */ |
| 4395 | |
| 4396 | local int inflate_fast(bl, bd, tl, td, s, z) |
| 4397 | uInt bl, bd; |
| 4398 | inflate_huft *tl, *td; |
| 4399 | inflate_blocks_statef *s; |
| 4400 | z_stream *z; |
| 4401 | { |
| 4402 | inflate_huft *t; /* temporary pointer */ |
| 4403 | uInt e; /* extra bits or operation */ |
| 4404 | uLong b; /* bit buffer */ |
| 4405 | uInt k; /* bits in bit buffer */ |
| 4406 | Bytef *p; /* input data pointer */ |
| 4407 | uInt n; /* bytes available there */ |
| 4408 | Bytef *q; /* output window write pointer */ |
| 4409 | uInt m; /* bytes to end of window or read pointer */ |
| 4410 | uInt ml; /* mask for literal/length tree */ |
| 4411 | uInt md; /* mask for distance tree */ |
| 4412 | uInt c; /* bytes to copy */ |
| 4413 | uInt d; /* distance back to copy from */ |
| 4414 | Bytef *r; /* copy source pointer */ |
| 4415 | |
| 4416 | /* load input, output, bit values */ |
| 4417 | LOAD |
| 4418 | |
| 4419 | /* initialize masks */ |
| 4420 | ml = inflate_mask[bl]; |
| 4421 | md = inflate_mask[bd]; |
| 4422 | |
| 4423 | /* do until not enough input or output space for fast loop */ |
| 4424 | do { /* assume called with m >= 258 && n >= 10 */ |
| 4425 | /* get literal/length code */ |
| 4426 | GRABBITS(20) /* max bits for literal/length code */ |
| 4427 | if ((e = (t = tl + ((uInt)b & ml))->exop) == 0) |
| 4428 | { |
| 4429 | DUMPBITS(t->bits) |
| 4430 | Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ? |
| 4431 | "inflate: * literal '%c'\n" : |
| 4432 | "inflate: * literal 0x%02x\n", t->base)); |
| 4433 | *q++ = (Byte)t->base; |
| 4434 | m--; |
| 4435 | continue; |
| 4436 | } |
| 4437 | do { |
| 4438 | DUMPBITS(t->bits) |
| 4439 | if (e & 16) |
| 4440 | { |
| 4441 | /* get extra bits for length */ |
| 4442 | e &= 15; |
| 4443 | c = t->base + ((uInt)b & inflate_mask[e]); |
| 4444 | DUMPBITS(e) |
| 4445 | Tracevv((stderr, "inflate: * length %u\n", c)); |
| 4446 | |
| 4447 | /* decode distance base of block to copy */ |
| 4448 | GRABBITS(15); /* max bits for distance code */ |
| 4449 | e = (t = td + ((uInt)b & md))->exop; |
| 4450 | do { |
| 4451 | DUMPBITS(t->bits) |
| 4452 | if (e & 16) |
| 4453 | { |
| 4454 | /* get extra bits to add to distance base */ |
| 4455 | e &= 15; |
| 4456 | GRABBITS(e) /* get extra bits (up to 13) */ |
| 4457 | d = t->base + ((uInt)b & inflate_mask[e]); |
| 4458 | DUMPBITS(e) |
| 4459 | Tracevv((stderr, "inflate: * distance %u\n", d)); |
| 4460 | |
| 4461 | /* do the copy */ |
| 4462 | m -= c; |
| 4463 | if ((uInt)(q - s->window) >= d) /* offset before dest */ |
| 4464 | { /* just copy */ |
| 4465 | r = q - d; |
| 4466 | *q++ = *r++; c--; /* minimum count is three, */ |
| 4467 | *q++ = *r++; c--; /* so unroll loop a little */ |
| 4468 | } |
| 4469 | else /* else offset after destination */ |
| 4470 | { |
| 4471 | e = d - (q - s->window); /* bytes from offset to end */ |
| 4472 | r = s->end - e; /* pointer to offset */ |
| 4473 | if (c > e) /* if source crosses, */ |
| 4474 | { |
| 4475 | c -= e; /* copy to end of window */ |
| 4476 | do { |
| 4477 | *q++ = *r++; |
| 4478 | } while (--e); |
| 4479 | r = s->window; /* copy rest from start of window */ |
| 4480 | } |
| 4481 | } |
| 4482 | do { /* copy all or what's left */ |
| 4483 | *q++ = *r++; |
| 4484 | } while (--c); |
| 4485 | break; |
| 4486 | } |
| 4487 | else if ((e & 64) == 0) |
| 4488 | e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop; |
| 4489 | else |
| 4490 | { |
| 4491 | z->msg = "invalid distance code"; |
| 4492 | UNGRAB |
| 4493 | UPDATE |
| 4494 | return Z_DATA_ERROR; |
| 4495 | } |
| 4496 | } while (1); |
| 4497 | break; |
| 4498 | } |
| 4499 | if ((e & 64) == 0) |
| 4500 | { |
| 4501 | if ((e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop) == 0) |
| 4502 | { |
| 4503 | DUMPBITS(t->bits) |
| 4504 | Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ? |
| 4505 | "inflate: * literal '%c'\n" : |
| 4506 | "inflate: * literal 0x%02x\n", t->base)); |
| 4507 | *q++ = (Byte)t->base; |
| 4508 | m--; |
| 4509 | break; |
| 4510 | } |
| 4511 | } |
| 4512 | else if (e & 32) |
| 4513 | { |
| 4514 | Tracevv((stderr, "inflate: * end of block\n")); |
| 4515 | UNGRAB |
| 4516 | UPDATE |
| 4517 | return Z_STREAM_END; |
| 4518 | } |
| 4519 | else |
| 4520 | { |
| 4521 | z->msg = "invalid literal/length code"; |
| 4522 | UNGRAB |
| 4523 | UPDATE |
| 4524 | return Z_DATA_ERROR; |
| 4525 | } |
| 4526 | } while (1); |
| 4527 | } while (m >= 258 && n >= 10); |
| 4528 | |
| 4529 | /* not enough input or output--restore pointers and return */ |
| 4530 | UNGRAB |
| 4531 | UPDATE |
| 4532 | return Z_OK; |
| 4533 | } |
| 4534 | |
| 4535 | |
| 4536 | /*+++++*/ |
| 4537 | /* zutil.c -- target dependent utility functions for the compression library |
| 4538 | * Copyright (C) 1995 Jean-loup Gailly. |
| 4539 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 4540 | */ |
| 4541 | |
| 4542 | /* From: zutil.c,v 1.8 1995/05/03 17:27:12 jloup Exp */ |
| 4543 | |
| 4544 | char *zlib_version = ZLIB_VERSION; |
| 4545 | |
| 4546 | char *z_errmsg[] = { |
| 4547 | "stream end", /* Z_STREAM_END 1 */ |
| 4548 | "", /* Z_OK 0 */ |
| 4549 | "file error", /* Z_ERRNO (-1) */ |
| 4550 | "stream error", /* Z_STREAM_ERROR (-2) */ |
| 4551 | "data error", /* Z_DATA_ERROR (-3) */ |
| 4552 | "insufficient memory", /* Z_MEM_ERROR (-4) */ |
| 4553 | "buffer error", /* Z_BUF_ERROR (-5) */ |
| 4554 | ""}; |
| 4555 | |
| 4556 | |
| 4557 | /*+++++*/ |
| 4558 | /* adler32.c -- compute the Adler-32 checksum of a data stream |
| 4559 | * Copyright (C) 1995 Mark Adler |
| 4560 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 4561 | */ |
| 4562 | |
| 4563 | /* From: adler32.c,v 1.6 1995/05/03 17:27:08 jloup Exp */ |
| 4564 | |
| 4565 | #define BASE 65521L /* largest prime smaller than 65536 */ |
| 4566 | #define NMAX 5552 |
| 4567 | /* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */ |
| 4568 | |
| 4569 | #define DO1(buf) {s1 += *buf++; s2 += s1;} |
| 4570 | #define DO2(buf) DO1(buf); DO1(buf); |
| 4571 | #define DO4(buf) DO2(buf); DO2(buf); |
| 4572 | #define DO8(buf) DO4(buf); DO4(buf); |
| 4573 | #define DO16(buf) DO8(buf); DO8(buf); |
| 4574 | |
| 4575 | /* ========================================================================= */ |
| 4576 | uLong adler32(adler, buf, len) |
| 4577 | uLong adler; |
| 4578 | Bytef *buf; |
| 4579 | uInt len; |
| 4580 | { |
| 4581 | uLong s1 = adler & 0xffff; |
| 4582 | uLong s2 = (adler >> 16) & 0xffff; |
| 4583 | int k; |
| 4584 | |
| 4585 | if (buf == Z_NULL) return 1L; |
| 4586 | |
| 4587 | while (len > 0) { |
| 4588 | k = len < NMAX ? len : NMAX; |
| 4589 | len -= k; |
| 4590 | while (k >= 16) { |
| 4591 | DO16(buf); |
| 4592 | k -= 16; |
| 4593 | } |
| 4594 | if (k != 0) do { |
| 4595 | DO1(buf); |
| 4596 | } while (--k); |
| 4597 | s1 %= BASE; |
| 4598 | s2 %= BASE; |
| 4599 | } |
| 4600 | return (s2 << 16) | s1; |
| 4601 | } |