[331] | 1 | /* inflate.c -- zlib decompression
|
---|
| 2 | * Copyright (C) 1995-2016 Mark Adler
|
---|
| 3 | * For conditions of distribution and use, see copyright notice in zlib.h
|
---|
| 4 | */
|
---|
| 5 |
|
---|
| 6 | /*
|
---|
| 7 | * Change history:
|
---|
| 8 | *
|
---|
| 9 | * 1.2.beta0 24 Nov 2002
|
---|
| 10 | * - First version -- complete rewrite of inflate to simplify code, avoid
|
---|
| 11 | * creation of window when not needed, minimize use of window when it is
|
---|
| 12 | * needed, make inffast.c even faster, implement gzip decoding, and to
|
---|
| 13 | * improve code readability and style over the previous zlib inflate code
|
---|
| 14 | *
|
---|
| 15 | * 1.2.beta1 25 Nov 2002
|
---|
| 16 | * - Use pointers for available input and output checking in inffast.c
|
---|
| 17 | * - Remove input and output counters in inffast.c
|
---|
| 18 | * - Change inffast.c entry and loop from avail_in >= 7 to >= 6
|
---|
| 19 | * - Remove unnecessary second byte pull from length extra in inffast.c
|
---|
| 20 | * - Unroll direct copy to three copies per loop in inffast.c
|
---|
| 21 | *
|
---|
| 22 | * 1.2.beta2 4 Dec 2002
|
---|
| 23 | * - Change external routine names to reduce potential conflicts
|
---|
| 24 | * - Correct filename to inffixed.h for fixed tables in inflate.c
|
---|
| 25 | * - Make hbuf[] unsigned char to match parameter type in inflate.c
|
---|
| 26 | * - Change strm->next_out[-state->offset] to *(strm->next_out - state->offset)
|
---|
| 27 | * to avoid negation problem on Alphas (64 bit) in inflate.c
|
---|
| 28 | *
|
---|
| 29 | * 1.2.beta3 22 Dec 2002
|
---|
| 30 | * - Add comments on state->bits assertion in inffast.c
|
---|
| 31 | * - Add comments on op field in inftrees.h
|
---|
| 32 | * - Fix bug in reuse of allocated window after inflateReset()
|
---|
| 33 | * - Remove bit fields--back to byte structure for speed
|
---|
| 34 | * - Remove distance extra == 0 check in inflate_fast()--only helps for lengths
|
---|
| 35 | * - Change post-increments to pre-increments in inflate_fast(), PPC biased?
|
---|
| 36 | * - Add compile time option, POSTINC, to use post-increments instead (Intel?)
|
---|
| 37 | * - Make MATCH copy in inflate() much faster for when inflate_fast() not used
|
---|
| 38 | * - Use local copies of stream next and avail values, as well as local bit
|
---|
| 39 | * buffer and bit count in inflate()--for speed when inflate_fast() not used
|
---|
| 40 | *
|
---|
| 41 | * 1.2.beta4 1 Jan 2003
|
---|
| 42 | * - Split ptr - 257 statements in inflate_table() to avoid compiler warnings
|
---|
| 43 | * - Move a comment on output buffer sizes from inffast.c to inflate.c
|
---|
| 44 | * - Add comments in inffast.c to introduce the inflate_fast() routine
|
---|
| 45 | * - Rearrange window copies in inflate_fast() for speed and simplification
|
---|
| 46 | * - Unroll last copy for window match in inflate_fast()
|
---|
| 47 | * - Use local copies of window variables in inflate_fast() for speed
|
---|
| 48 | * - Pull out common wnext == 0 case for speed in inflate_fast()
|
---|
| 49 | * - Make op and len in inflate_fast() unsigned for consistency
|
---|
| 50 | * - Add FAR to lcode and dcode declarations in inflate_fast()
|
---|
| 51 | * - Simplified bad distance check in inflate_fast()
|
---|
| 52 | * - Added inflateBackInit(), inflateBack(), and inflateBackEnd() in new
|
---|
| 53 | * source file infback.c to provide a call-back interface to inflate for
|
---|
| 54 | * programs like gzip and unzip -- uses window as output buffer to avoid
|
---|
| 55 | * window copying
|
---|
| 56 | *
|
---|
| 57 | * 1.2.beta5 1 Jan 2003
|
---|
| 58 | * - Improved inflateBack() interface to allow the caller to provide initial
|
---|
| 59 | * input in strm.
|
---|
| 60 | * - Fixed stored blocks bug in inflateBack()
|
---|
| 61 | *
|
---|
| 62 | * 1.2.beta6 4 Jan 2003
|
---|
| 63 | * - Added comments in inffast.c on effectiveness of POSTINC
|
---|
| 64 | * - Typecasting all around to reduce compiler warnings
|
---|
| 65 | * - Changed loops from while (1) or do {} while (1) to for (;;), again to
|
---|
| 66 | * make compilers happy
|
---|
| 67 | * - Changed type of window in inflateBackInit() to unsigned char *
|
---|
| 68 | *
|
---|
| 69 | * 1.2.beta7 27 Jan 2003
|
---|
| 70 | * - Changed many types to unsigned or unsigned short to avoid warnings
|
---|
| 71 | * - Added inflateCopy() function
|
---|
| 72 | *
|
---|
| 73 | * 1.2.0 9 Mar 2003
|
---|
| 74 | * - Changed inflateBack() interface to provide separate opaque descriptors
|
---|
| 75 | * for the in() and out() functions
|
---|
| 76 | * - Changed inflateBack() argument and in_func typedef to swap the length
|
---|
| 77 | * and buffer address return values for the input function
|
---|
| 78 | * - Check next_in and next_out for Z_NULL on entry to inflate()
|
---|
| 79 | *
|
---|
| 80 | * The history for versions after 1.2.0 are in ChangeLog in zlib distribution.
|
---|
| 81 | */
|
---|
| 82 |
|
---|
| 83 | #include "zutil.h"
|
---|
| 84 | #include "inftrees.h"
|
---|
| 85 | #include "inflate.h"
|
---|
| 86 | #include "inffast.h"
|
---|
| 87 |
|
---|
| 88 | #ifdef MAKEFIXED
|
---|
| 89 | # ifndef BUILDFIXED
|
---|
| 90 | # define BUILDFIXED
|
---|
| 91 | # endif
|
---|
| 92 | #endif
|
---|
| 93 |
|
---|
| 94 | /* function prototypes */
|
---|
| 95 | local int inflateStateCheck OF((z_streamp strm));
|
---|
| 96 | local void fixedtables OF((struct inflate_state FAR *state));
|
---|
| 97 | local int updatewindow OF((z_streamp strm, const unsigned char FAR *end,
|
---|
| 98 | unsigned copy));
|
---|
| 99 | #ifdef BUILDFIXED
|
---|
| 100 | void makefixed OF((void));
|
---|
| 101 | #endif
|
---|
| 102 | local unsigned syncsearch OF((unsigned FAR *have, const unsigned char FAR *buf,
|
---|
| 103 | unsigned len));
|
---|
| 104 |
|
---|
| 105 | local int inflateStateCheck(strm)
|
---|
| 106 | z_streamp strm;
|
---|
| 107 | {
|
---|
| 108 | struct inflate_state FAR *state;
|
---|
| 109 | if (strm == Z_NULL ||
|
---|
| 110 | strm->zalloc == (alloc_func)0 || strm->zfree == (free_func)0)
|
---|
| 111 | return 1;
|
---|
| 112 | state = (struct inflate_state FAR *)strm->state;
|
---|
| 113 | if (state == Z_NULL || state->strm != strm ||
|
---|
| 114 | state->mode < HEAD || state->mode > SYNC)
|
---|
| 115 | return 1;
|
---|
| 116 | return 0;
|
---|
| 117 | }
|
---|
| 118 |
|
---|
| 119 | int ZEXPORT inflateResetKeep(strm)
|
---|
| 120 | z_streamp strm;
|
---|
| 121 | {
|
---|
| 122 | struct inflate_state FAR *state;
|
---|
| 123 |
|
---|
| 124 | if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
|
---|
| 125 | state = (struct inflate_state FAR *)strm->state;
|
---|
| 126 | strm->total_in = strm->total_out = state->total = 0;
|
---|
| 127 | strm->msg = Z_NULL;
|
---|
| 128 | if (state->wrap) /* to support ill-conceived Java test suite */
|
---|
| 129 | strm->adler = state->wrap & 1;
|
---|
| 130 | state->mode = HEAD;
|
---|
| 131 | state->last = 0;
|
---|
| 132 | state->havedict = 0;
|
---|
| 133 | state->dmax = 32768U;
|
---|
| 134 | state->head = Z_NULL;
|
---|
| 135 | state->hold = 0;
|
---|
| 136 | state->bits = 0;
|
---|
| 137 | state->lencode = state->distcode = state->next = state->codes;
|
---|
| 138 | state->sane = 1;
|
---|
| 139 | state->back = -1;
|
---|
| 140 | Tracev((stderr, "inflate: reset\n"));
|
---|
| 141 | return Z_OK;
|
---|
| 142 | }
|
---|
| 143 |
|
---|
| 144 | int ZEXPORT inflateReset(strm)
|
---|
| 145 | z_streamp strm;
|
---|
| 146 | {
|
---|
| 147 | struct inflate_state FAR *state;
|
---|
| 148 |
|
---|
| 149 | if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
|
---|
| 150 | state = (struct inflate_state FAR *)strm->state;
|
---|
| 151 | state->wsize = 0;
|
---|
| 152 | state->whave = 0;
|
---|
| 153 | state->wnext = 0;
|
---|
| 154 | return inflateResetKeep(strm);
|
---|
| 155 | }
|
---|
| 156 |
|
---|
| 157 | int ZEXPORT inflateReset2(strm, windowBits)
|
---|
| 158 | z_streamp strm;
|
---|
| 159 | int windowBits;
|
---|
| 160 | {
|
---|
| 161 | int wrap;
|
---|
| 162 | struct inflate_state FAR *state;
|
---|
| 163 |
|
---|
| 164 | /* get the state */
|
---|
| 165 | if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
|
---|
| 166 | state = (struct inflate_state FAR *)strm->state;
|
---|
| 167 |
|
---|
| 168 | /* extract wrap request from windowBits parameter */
|
---|
| 169 | if (windowBits < 0) {
|
---|
| 170 | wrap = 0;
|
---|
| 171 | windowBits = -windowBits;
|
---|
| 172 | }
|
---|
| 173 | else {
|
---|
| 174 | wrap = (windowBits >> 4) + 5;
|
---|
| 175 | #ifdef GUNZIP
|
---|
| 176 | if (windowBits < 48)
|
---|
| 177 | windowBits &= 15;
|
---|
| 178 | #endif
|
---|
| 179 | }
|
---|
| 180 |
|
---|
| 181 | /* set number of window bits, free window if different */
|
---|
| 182 | if (windowBits && (windowBits < 8 || windowBits > 15))
|
---|
| 183 | return Z_STREAM_ERROR;
|
---|
| 184 | if (state->window != Z_NULL && state->wbits != (unsigned)windowBits) {
|
---|
| 185 | ZFREE(strm, state->window);
|
---|
| 186 | state->window = Z_NULL;
|
---|
| 187 | }
|
---|
| 188 |
|
---|
| 189 | /* update state and reset the rest of it */
|
---|
| 190 | state->wrap = wrap;
|
---|
| 191 | state->wbits = (unsigned)windowBits;
|
---|
| 192 | return inflateReset(strm);
|
---|
| 193 | }
|
---|
| 194 |
|
---|
| 195 | int ZEXPORT inflateInit2_(strm, windowBits, version, stream_size)
|
---|
| 196 | z_streamp strm;
|
---|
| 197 | int windowBits;
|
---|
| 198 | const char *version;
|
---|
| 199 | int stream_size;
|
---|
| 200 | {
|
---|
| 201 | int ret;
|
---|
| 202 | struct inflate_state FAR *state;
|
---|
| 203 |
|
---|
| 204 | if (version == Z_NULL || version[0] != ZLIB_VERSION[0] ||
|
---|
| 205 | stream_size != (int)(sizeof(z_stream)))
|
---|
| 206 | return Z_VERSION_ERROR;
|
---|
| 207 | if (strm == Z_NULL) return Z_STREAM_ERROR;
|
---|
| 208 | strm->msg = Z_NULL; /* in case we return an error */
|
---|
| 209 | if (strm->zalloc == (alloc_func)0) {
|
---|
| 210 | #ifdef Z_SOLO
|
---|
| 211 | return Z_STREAM_ERROR;
|
---|
| 212 | #else
|
---|
| 213 | strm->zalloc = zcalloc;
|
---|
| 214 | strm->opaque = (voidpf)0;
|
---|
| 215 | #endif
|
---|
| 216 | }
|
---|
| 217 | if (strm->zfree == (free_func)0)
|
---|
| 218 | #ifdef Z_SOLO
|
---|
| 219 | return Z_STREAM_ERROR;
|
---|
| 220 | #else
|
---|
| 221 | strm->zfree = zcfree;
|
---|
| 222 | #endif
|
---|
| 223 | state = (struct inflate_state FAR *)
|
---|
| 224 | ZALLOC(strm, 1, sizeof(struct inflate_state));
|
---|
| 225 | if (state == Z_NULL) return Z_MEM_ERROR;
|
---|
| 226 | Tracev((stderr, "inflate: allocated\n"));
|
---|
| 227 | strm->state = (struct internal_state FAR *)state;
|
---|
| 228 | state->strm = strm;
|
---|
| 229 | state->window = Z_NULL;
|
---|
| 230 | state->mode = HEAD; /* to pass state test in inflateReset2() */
|
---|
| 231 | ret = inflateReset2(strm, windowBits);
|
---|
| 232 | if (ret != Z_OK) {
|
---|
| 233 | ZFREE(strm, state);
|
---|
| 234 | strm->state = Z_NULL;
|
---|
| 235 | }
|
---|
| 236 | return ret;
|
---|
| 237 | }
|
---|
| 238 |
|
---|
| 239 | int ZEXPORT inflateInit_(strm, version, stream_size)
|
---|
| 240 | z_streamp strm;
|
---|
| 241 | const char *version;
|
---|
| 242 | int stream_size;
|
---|
| 243 | {
|
---|
| 244 | return inflateInit2_(strm, DEF_WBITS, version, stream_size);
|
---|
| 245 | }
|
---|
| 246 |
|
---|
| 247 | int ZEXPORT inflatePrime(strm, bits, value)
|
---|
| 248 | z_streamp strm;
|
---|
| 249 | int bits;
|
---|
| 250 | int value;
|
---|
| 251 | {
|
---|
| 252 | struct inflate_state FAR *state;
|
---|
| 253 |
|
---|
| 254 | if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
|
---|
| 255 | state = (struct inflate_state FAR *)strm->state;
|
---|
| 256 | if (bits < 0) {
|
---|
| 257 | state->hold = 0;
|
---|
| 258 | state->bits = 0;
|
---|
| 259 | return Z_OK;
|
---|
| 260 | }
|
---|
| 261 | if (bits > 16 || state->bits + (uInt)bits > 32) return Z_STREAM_ERROR;
|
---|
| 262 | value &= (1L << bits) - 1;
|
---|
| 263 | state->hold += (unsigned)value << state->bits;
|
---|
| 264 | state->bits += (uInt)bits;
|
---|
| 265 | return Z_OK;
|
---|
| 266 | }
|
---|
| 267 |
|
---|
| 268 | /*
|
---|
| 269 | Return state with length and distance decoding tables and index sizes set to
|
---|
| 270 | fixed code decoding. Normally this returns fixed tables from inffixed.h.
|
---|
| 271 | If BUILDFIXED is defined, then instead this routine builds the tables the
|
---|
| 272 | first time it's called, and returns those tables the first time and
|
---|
| 273 | thereafter. This reduces the size of the code by about 2K bytes, in
|
---|
| 274 | exchange for a little execution time. However, BUILDFIXED should not be
|
---|
| 275 | used for threaded applications, since the rewriting of the tables and virgin
|
---|
| 276 | may not be thread-safe.
|
---|
| 277 | */
|
---|
| 278 | local void fixedtables(state)
|
---|
| 279 | struct inflate_state FAR *state;
|
---|
| 280 | {
|
---|
| 281 | #ifdef BUILDFIXED
|
---|
| 282 | static int virgin = 1;
|
---|
| 283 | static code *lenfix, *distfix;
|
---|
| 284 | static code fixed[544];
|
---|
| 285 |
|
---|
| 286 | /* build fixed huffman tables if first call (may not be thread safe) */
|
---|
| 287 | if (virgin) {
|
---|
| 288 | unsigned sym, bits;
|
---|
| 289 | static code *next;
|
---|
| 290 |
|
---|
| 291 | /* literal/length table */
|
---|
| 292 | sym = 0;
|
---|
| 293 | while (sym < 144) state->lens[sym++] = 8;
|
---|
| 294 | while (sym < 256) state->lens[sym++] = 9;
|
---|
| 295 | while (sym < 280) state->lens[sym++] = 7;
|
---|
| 296 | while (sym < 288) state->lens[sym++] = 8;
|
---|
| 297 | next = fixed;
|
---|
| 298 | lenfix = next;
|
---|
| 299 | bits = 9;
|
---|
| 300 | inflate_table(LENS, state->lens, 288, &(next), &(bits), state->work);
|
---|
| 301 |
|
---|
| 302 | /* distance table */
|
---|
| 303 | sym = 0;
|
---|
| 304 | while (sym < 32) state->lens[sym++] = 5;
|
---|
| 305 | distfix = next;
|
---|
| 306 | bits = 5;
|
---|
| 307 | inflate_table(DISTS, state->lens, 32, &(next), &(bits), state->work);
|
---|
| 308 |
|
---|
| 309 | /* do this just once */
|
---|
| 310 | virgin = 0;
|
---|
| 311 | }
|
---|
| 312 | #else /* !BUILDFIXED */
|
---|
| 313 | # include "inffixed.h"
|
---|
| 314 | #endif /* BUILDFIXED */
|
---|
| 315 | state->lencode = lenfix;
|
---|
| 316 | state->lenbits = 9;
|
---|
| 317 | state->distcode = distfix;
|
---|
| 318 | state->distbits = 5;
|
---|
| 319 | }
|
---|
| 320 |
|
---|
| 321 | #ifdef MAKEFIXED
|
---|
| 322 | #include <stdio.h>
|
---|
| 323 |
|
---|
| 324 | /*
|
---|
| 325 | Write out the inffixed.h that is #include'd above. Defining MAKEFIXED also
|
---|
| 326 | defines BUILDFIXED, so the tables are built on the fly. makefixed() writes
|
---|
| 327 | those tables to stdout, which would be piped to inffixed.h. A small program
|
---|
| 328 | can simply call makefixed to do this:
|
---|
| 329 |
|
---|
| 330 | void makefixed(void);
|
---|
| 331 |
|
---|
| 332 | int main(void)
|
---|
| 333 | {
|
---|
| 334 | makefixed();
|
---|
| 335 | return 0;
|
---|
| 336 | }
|
---|
| 337 |
|
---|
| 338 | Then that can be linked with zlib built with MAKEFIXED defined and run:
|
---|
| 339 |
|
---|
| 340 | a.out > inffixed.h
|
---|
| 341 | */
|
---|
| 342 | void makefixed()
|
---|
| 343 | {
|
---|
| 344 | unsigned low, size;
|
---|
| 345 | struct inflate_state state;
|
---|
| 346 |
|
---|
| 347 | fixedtables(&state);
|
---|
| 348 | puts(" /* inffixed.h -- table for decoding fixed codes");
|
---|
| 349 | puts(" * Generated automatically by makefixed().");
|
---|
| 350 | puts(" */");
|
---|
| 351 | puts("");
|
---|
| 352 | puts(" /* WARNING: this file should *not* be used by applications.");
|
---|
| 353 | puts(" It is part of the implementation of this library and is");
|
---|
| 354 | puts(" subject to change. Applications should only use zlib.h.");
|
---|
| 355 | puts(" */");
|
---|
| 356 | puts("");
|
---|
| 357 | size = 1U << 9;
|
---|
| 358 | printf(" static const code lenfix[%u] = {", size);
|
---|
| 359 | low = 0;
|
---|
| 360 | for (;;) {
|
---|
| 361 | if ((low % 7) == 0) printf("\n ");
|
---|
| 362 | printf("{%u,%u,%d}", (low & 127) == 99 ? 64 : state.lencode[low].op,
|
---|
| 363 | state.lencode[low].bits, state.lencode[low].val);
|
---|
| 364 | if (++low == size) break;
|
---|
| 365 | putchar(',');
|
---|
| 366 | }
|
---|
| 367 | puts("\n };");
|
---|
| 368 | size = 1U << 5;
|
---|
| 369 | printf("\n static const code distfix[%u] = {", size);
|
---|
| 370 | low = 0;
|
---|
| 371 | for (;;) {
|
---|
| 372 | if ((low % 6) == 0) printf("\n ");
|
---|
| 373 | printf("{%u,%u,%d}", state.distcode[low].op, state.distcode[low].bits,
|
---|
| 374 | state.distcode[low].val);
|
---|
| 375 | if (++low == size) break;
|
---|
| 376 | putchar(',');
|
---|
| 377 | }
|
---|
| 378 | puts("\n };");
|
---|
| 379 | }
|
---|
| 380 | #endif /* MAKEFIXED */
|
---|
| 381 |
|
---|
| 382 | /*
|
---|
| 383 | Update the window with the last wsize (normally 32K) bytes written before
|
---|
| 384 | returning. If window does not exist yet, create it. This is only called
|
---|
| 385 | when a window is already in use, or when output has been written during this
|
---|
| 386 | inflate call, but the end of the deflate stream has not been reached yet.
|
---|
| 387 | It is also called to create a window for dictionary data when a dictionary
|
---|
| 388 | is loaded.
|
---|
| 389 |
|
---|
| 390 | Providing output buffers larger than 32K to inflate() should provide a speed
|
---|
| 391 | advantage, since only the last 32K of output is copied to the sliding window
|
---|
| 392 | upon return from inflate(), and since all distances after the first 32K of
|
---|
| 393 | output will fall in the output data, making match copies simpler and faster.
|
---|
| 394 | The advantage may be dependent on the size of the processor's data caches.
|
---|
| 395 | */
|
---|
| 396 | local int updatewindow(strm, end, copy)
|
---|
| 397 | z_streamp strm;
|
---|
| 398 | const Bytef *end;
|
---|
| 399 | unsigned copy;
|
---|
| 400 | {
|
---|
| 401 | struct inflate_state FAR *state;
|
---|
| 402 | unsigned dist;
|
---|
| 403 |
|
---|
| 404 | state = (struct inflate_state FAR *)strm->state;
|
---|
| 405 |
|
---|
| 406 | /* if it hasn't been done already, allocate space for the window */
|
---|
| 407 | if (state->window == Z_NULL) {
|
---|
| 408 | state->window = (unsigned char FAR *)
|
---|
| 409 | ZALLOC(strm, 1U << state->wbits,
|
---|
| 410 | sizeof(unsigned char));
|
---|
| 411 | if (state->window == Z_NULL) return 1;
|
---|
| 412 | }
|
---|
| 413 |
|
---|
| 414 | /* if window not in use yet, initialize */
|
---|
| 415 | if (state->wsize == 0) {
|
---|
| 416 | state->wsize = 1U << state->wbits;
|
---|
| 417 | state->wnext = 0;
|
---|
| 418 | state->whave = 0;
|
---|
| 419 | }
|
---|
| 420 |
|
---|
| 421 | /* copy state->wsize or less output bytes into the circular window */
|
---|
| 422 | if (copy >= state->wsize) {
|
---|
| 423 | zmemcpy(state->window, end - state->wsize, state->wsize);
|
---|
| 424 | state->wnext = 0;
|
---|
| 425 | state->whave = state->wsize;
|
---|
| 426 | }
|
---|
| 427 | else {
|
---|
| 428 | dist = state->wsize - state->wnext;
|
---|
| 429 | if (dist > copy) dist = copy;
|
---|
| 430 | zmemcpy(state->window + state->wnext, end - copy, dist);
|
---|
| 431 | copy -= dist;
|
---|
| 432 | if (copy) {
|
---|
| 433 | zmemcpy(state->window, end - copy, copy);
|
---|
| 434 | state->wnext = copy;
|
---|
| 435 | state->whave = state->wsize;
|
---|
| 436 | }
|
---|
| 437 | else {
|
---|
| 438 | state->wnext += dist;
|
---|
| 439 | if (state->wnext == state->wsize) state->wnext = 0;
|
---|
| 440 | if (state->whave < state->wsize) state->whave += dist;
|
---|
| 441 | }
|
---|
| 442 | }
|
---|
| 443 | return 0;
|
---|
| 444 | }
|
---|
| 445 |
|
---|
| 446 | /* Macros for inflate(): */
|
---|
| 447 |
|
---|
| 448 | /* check function to use adler32() for zlib or crc32() for gzip */
|
---|
| 449 | #ifdef GUNZIP
|
---|
| 450 | # define UPDATE(check, buf, len) \
|
---|
| 451 | (state->flags ? crc32(check, buf, len) : adler32(check, buf, len))
|
---|
| 452 | #else
|
---|
| 453 | # define UPDATE(check, buf, len) adler32(check, buf, len)
|
---|
| 454 | #endif
|
---|
| 455 |
|
---|
| 456 | /* check macros for header crc */
|
---|
| 457 | #ifdef GUNZIP
|
---|
| 458 | # define CRC2(check, word) \
|
---|
| 459 | do { \
|
---|
| 460 | hbuf[0] = (unsigned char)(word); \
|
---|
| 461 | hbuf[1] = (unsigned char)((word) >> 8); \
|
---|
| 462 | check = crc32(check, hbuf, 2); \
|
---|
| 463 | } while (0)
|
---|
| 464 |
|
---|
| 465 | # define CRC4(check, word) \
|
---|
| 466 | do { \
|
---|
| 467 | hbuf[0] = (unsigned char)(word); \
|
---|
| 468 | hbuf[1] = (unsigned char)((word) >> 8); \
|
---|
| 469 | hbuf[2] = (unsigned char)((word) >> 16); \
|
---|
| 470 | hbuf[3] = (unsigned char)((word) >> 24); \
|
---|
| 471 | check = crc32(check, hbuf, 4); \
|
---|
| 472 | } while (0)
|
---|
| 473 | #endif
|
---|
| 474 |
|
---|
| 475 | /* Load registers with state in inflate() for speed */
|
---|
| 476 | #define LOAD() \
|
---|
| 477 | do { \
|
---|
| 478 | put = strm->next_out; \
|
---|
| 479 | left = strm->avail_out; \
|
---|
| 480 | next = strm->next_in; \
|
---|
| 481 | have = strm->avail_in; \
|
---|
| 482 | hold = state->hold; \
|
---|
| 483 | bits = state->bits; \
|
---|
| 484 | } while (0)
|
---|
| 485 |
|
---|
| 486 | /* Restore state from registers in inflate() */
|
---|
| 487 | #define RESTORE() \
|
---|
| 488 | do { \
|
---|
| 489 | strm->next_out = put; \
|
---|
| 490 | strm->avail_out = left; \
|
---|
| 491 | strm->next_in = next; \
|
---|
| 492 | strm->avail_in = have; \
|
---|
| 493 | state->hold = hold; \
|
---|
| 494 | state->bits = bits; \
|
---|
| 495 | } while (0)
|
---|
| 496 |
|
---|
| 497 | /* Clear the input bit accumulator */
|
---|
| 498 | #define INITBITS() \
|
---|
| 499 | do { \
|
---|
| 500 | hold = 0; \
|
---|
| 501 | bits = 0; \
|
---|
| 502 | } while (0)
|
---|
| 503 |
|
---|
| 504 | /* Get a byte of input into the bit accumulator, or return from inflate()
|
---|
| 505 | if there is no input available. */
|
---|
| 506 | #define PULLBYTE() \
|
---|
| 507 | do { \
|
---|
| 508 | if (have == 0) goto inf_leave; \
|
---|
| 509 | have--; \
|
---|
| 510 | hold += (unsigned long)(*next++) << bits; \
|
---|
| 511 | bits += 8; \
|
---|
| 512 | } while (0)
|
---|
| 513 |
|
---|
| 514 | /* Assure that there are at least n bits in the bit accumulator. If there is
|
---|
| 515 | not enough available input to do that, then return from inflate(). */
|
---|
| 516 | #define NEEDBITS(n) \
|
---|
| 517 | do { \
|
---|
| 518 | while (bits < (unsigned)(n)) \
|
---|
| 519 | PULLBYTE(); \
|
---|
| 520 | } while (0)
|
---|
| 521 |
|
---|
| 522 | /* Return the low n bits of the bit accumulator (n < 16) */
|
---|
| 523 | #define BITS(n) \
|
---|
| 524 | ((unsigned)hold & ((1U << (n)) - 1))
|
---|
| 525 |
|
---|
| 526 | /* Remove n bits from the bit accumulator */
|
---|
| 527 | #define DROPBITS(n) \
|
---|
| 528 | do { \
|
---|
| 529 | hold >>= (n); \
|
---|
| 530 | bits -= (unsigned)(n); \
|
---|
| 531 | } while (0)
|
---|
| 532 |
|
---|
| 533 | /* Remove zero to seven bits as needed to go to a byte boundary */
|
---|
| 534 | #define BYTEBITS() \
|
---|
| 535 | do { \
|
---|
| 536 | hold >>= bits & 7; \
|
---|
| 537 | bits -= bits & 7; \
|
---|
| 538 | } while (0)
|
---|
| 539 |
|
---|
| 540 | /*
|
---|
| 541 | inflate() uses a state machine to process as much input data and generate as
|
---|
| 542 | much output data as possible before returning. The state machine is
|
---|
| 543 | structured roughly as follows:
|
---|
| 544 |
|
---|
| 545 | for (;;) switch (state) {
|
---|
| 546 | ...
|
---|
| 547 | case STATEn:
|
---|
| 548 | if (not enough input data or output space to make progress)
|
---|
| 549 | return;
|
---|
| 550 | ... make progress ...
|
---|
| 551 | state = STATEm;
|
---|
| 552 | break;
|
---|
| 553 | ...
|
---|
| 554 | }
|
---|
| 555 |
|
---|
| 556 | so when inflate() is called again, the same case is attempted again, and
|
---|
| 557 | if the appropriate resources are provided, the machine proceeds to the
|
---|
| 558 | next state. The NEEDBITS() macro is usually the way the state evaluates
|
---|
| 559 | whether it can proceed or should return. NEEDBITS() does the return if
|
---|
| 560 | the requested bits are not available. The typical use of the BITS macros
|
---|
| 561 | is:
|
---|
| 562 |
|
---|
| 563 | NEEDBITS(n);
|
---|
| 564 | ... do something with BITS(n) ...
|
---|
| 565 | DROPBITS(n);
|
---|
| 566 |
|
---|
| 567 | where NEEDBITS(n) either returns from inflate() if there isn't enough
|
---|
| 568 | input left to load n bits into the accumulator, or it continues. BITS(n)
|
---|
| 569 | gives the low n bits in the accumulator. When done, DROPBITS(n) drops
|
---|
| 570 | the low n bits off the accumulator. INITBITS() clears the accumulator
|
---|
| 571 | and sets the number of available bits to zero. BYTEBITS() discards just
|
---|
| 572 | enough bits to put the accumulator on a byte boundary. After BYTEBITS()
|
---|
| 573 | and a NEEDBITS(8), then BITS(8) would return the next byte in the stream.
|
---|
| 574 |
|
---|
| 575 | NEEDBITS(n) uses PULLBYTE() to get an available byte of input, or to return
|
---|
| 576 | if there is no input available. The decoding of variable length codes uses
|
---|
| 577 | PULLBYTE() directly in order to pull just enough bytes to decode the next
|
---|
| 578 | code, and no more.
|
---|
| 579 |
|
---|
| 580 | Some states loop until they get enough input, making sure that enough
|
---|
| 581 | state information is maintained to continue the loop where it left off
|
---|
| 582 | if NEEDBITS() returns in the loop. For example, want, need, and keep
|
---|
| 583 | would all have to actually be part of the saved state in case NEEDBITS()
|
---|
| 584 | returns:
|
---|
| 585 |
|
---|
| 586 | case STATEw:
|
---|
| 587 | while (want < need) {
|
---|
| 588 | NEEDBITS(n);
|
---|
| 589 | keep[want++] = BITS(n);
|
---|
| 590 | DROPBITS(n);
|
---|
| 591 | }
|
---|
| 592 | state = STATEx;
|
---|
| 593 | case STATEx:
|
---|
| 594 |
|
---|
| 595 | As shown above, if the next state is also the next case, then the break
|
---|
| 596 | is omitted.
|
---|
| 597 |
|
---|
| 598 | A state may also return if there is not enough output space available to
|
---|
| 599 | complete that state. Those states are copying stored data, writing a
|
---|
| 600 | literal byte, and copying a matching string.
|
---|
| 601 |
|
---|
| 602 | When returning, a "goto inf_leave" is used to update the total counters,
|
---|
| 603 | update the check value, and determine whether any progress has been made
|
---|
| 604 | during that inflate() call in order to return the proper return code.
|
---|
| 605 | Progress is defined as a change in either strm->avail_in or strm->avail_out.
|
---|
| 606 | When there is a window, goto inf_leave will update the window with the last
|
---|
| 607 | output written. If a goto inf_leave occurs in the middle of decompression
|
---|
| 608 | and there is no window currently, goto inf_leave will create one and copy
|
---|
| 609 | output to the window for the next call of inflate().
|
---|
| 610 |
|
---|
| 611 | In this implementation, the flush parameter of inflate() only affects the
|
---|
| 612 | return code (per zlib.h). inflate() always writes as much as possible to
|
---|
| 613 | strm->next_out, given the space available and the provided input--the effect
|
---|
| 614 | documented in zlib.h of Z_SYNC_FLUSH. Furthermore, inflate() always defers
|
---|
| 615 | the allocation of and copying into a sliding window until necessary, which
|
---|
| 616 | provides the effect documented in zlib.h for Z_FINISH when the entire input
|
---|
| 617 | stream available. So the only thing the flush parameter actually does is:
|
---|
| 618 | when flush is set to Z_FINISH, inflate() cannot return Z_OK. Instead it
|
---|
| 619 | will return Z_BUF_ERROR if it has not reached the end of the stream.
|
---|
| 620 | */
|
---|
| 621 |
|
---|
| 622 | int ZEXPORT inflate(strm, flush)
|
---|
| 623 | z_streamp strm;
|
---|
| 624 | int flush;
|
---|
| 625 | {
|
---|
| 626 | struct inflate_state FAR *state;
|
---|
| 627 | z_const unsigned char FAR *next; /* next input */
|
---|
| 628 | unsigned char FAR *put; /* next output */
|
---|
| 629 | unsigned have, left; /* available input and output */
|
---|
| 630 | unsigned long hold; /* bit buffer */
|
---|
| 631 | unsigned bits; /* bits in bit buffer */
|
---|
| 632 | unsigned in, out; /* save starting available input and output */
|
---|
| 633 | unsigned copy; /* number of stored or match bytes to copy */
|
---|
| 634 | unsigned char FAR *from; /* where to copy match bytes from */
|
---|
| 635 | code here; /* current decoding table entry */
|
---|
| 636 | code last; /* parent table entry */
|
---|
| 637 | unsigned len; /* length to copy for repeats, bits to drop */
|
---|
| 638 | int ret; /* return code */
|
---|
| 639 | #ifdef GUNZIP
|
---|
| 640 | unsigned char hbuf[4]; /* buffer for gzip header crc calculation */
|
---|
| 641 | #endif
|
---|
| 642 | static const unsigned short order[19] = /* permutation of code lengths */
|
---|
| 643 | {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
|
---|
| 644 |
|
---|
| 645 | if (inflateStateCheck(strm) || strm->next_out == Z_NULL ||
|
---|
| 646 | (strm->next_in == Z_NULL && strm->avail_in != 0))
|
---|
| 647 | return Z_STREAM_ERROR;
|
---|
| 648 |
|
---|
| 649 | state = (struct inflate_state FAR *)strm->state;
|
---|
| 650 | if (state->mode == TYPE) state->mode = TYPEDO; /* skip check */
|
---|
| 651 | LOAD();
|
---|
| 652 | in = have;
|
---|
| 653 | out = left;
|
---|
| 654 | ret = Z_OK;
|
---|
| 655 | for (;;)
|
---|
| 656 | switch (state->mode) {
|
---|
| 657 | case HEAD:
|
---|
| 658 | if (state->wrap == 0) {
|
---|
| 659 | state->mode = TYPEDO;
|
---|
| 660 | break;
|
---|
| 661 | }
|
---|
| 662 | NEEDBITS(16);
|
---|
| 663 | #ifdef GUNZIP
|
---|
| 664 | if ((state->wrap & 2) && hold == 0x8b1f) { /* gzip header */
|
---|
| 665 | if (state->wbits == 0)
|
---|
| 666 | state->wbits = 15;
|
---|
| 667 | state->check = crc32(0L, Z_NULL, 0);
|
---|
| 668 | CRC2(state->check, hold);
|
---|
| 669 | INITBITS();
|
---|
| 670 | state->mode = FLAGS;
|
---|
| 671 | break;
|
---|
| 672 | }
|
---|
| 673 | state->flags = 0; /* expect zlib header */
|
---|
| 674 | if (state->head != Z_NULL)
|
---|
| 675 | state->head->done = -1;
|
---|
| 676 | if (!(state->wrap & 1) || /* check if zlib header allowed */
|
---|
| 677 | #else
|
---|
| 678 | if (
|
---|
| 679 | #endif
|
---|
| 680 | ((BITS(8) << 8) + (hold >> 8)) % 31) {
|
---|
| 681 | strm->msg = (char *)"incorrect header check";
|
---|
| 682 | state->mode = BAD;
|
---|
| 683 | break;
|
---|
| 684 | }
|
---|
| 685 | if (BITS(4) != Z_DEFLATED) {
|
---|
| 686 | strm->msg = (char *)"unknown compression method";
|
---|
| 687 | state->mode = BAD;
|
---|
| 688 | break;
|
---|
| 689 | }
|
---|
| 690 | DROPBITS(4);
|
---|
| 691 | len = BITS(4) + 8;
|
---|
| 692 | if (state->wbits == 0)
|
---|
| 693 | state->wbits = len;
|
---|
| 694 | if (len > 15 || len > state->wbits) {
|
---|
| 695 | strm->msg = (char *)"invalid window size";
|
---|
| 696 | state->mode = BAD;
|
---|
| 697 | break;
|
---|
| 698 | }
|
---|
| 699 | state->dmax = 1U << len;
|
---|
| 700 | Tracev((stderr, "inflate: zlib header ok\n"));
|
---|
| 701 | strm->adler = state->check = adler32(0L, Z_NULL, 0);
|
---|
| 702 | state->mode = hold & 0x200 ? DICTID : TYPE;
|
---|
| 703 | INITBITS();
|
---|
| 704 | break;
|
---|
| 705 | #ifdef GUNZIP
|
---|
| 706 | case FLAGS:
|
---|
| 707 | NEEDBITS(16);
|
---|
| 708 | state->flags = (int)(hold);
|
---|
| 709 | if ((state->flags & 0xff) != Z_DEFLATED) {
|
---|
| 710 | strm->msg = (char *)"unknown compression method";
|
---|
| 711 | state->mode = BAD;
|
---|
| 712 | break;
|
---|
| 713 | }
|
---|
| 714 | if (state->flags & 0xe000) {
|
---|
| 715 | strm->msg = (char *)"unknown header flags set";
|
---|
| 716 | state->mode = BAD;
|
---|
| 717 | break;
|
---|
| 718 | }
|
---|
| 719 | if (state->head != Z_NULL)
|
---|
| 720 | state->head->text = (int)((hold >> 8) & 1);
|
---|
| 721 | if ((state->flags & 0x0200) && (state->wrap & 4))
|
---|
| 722 | CRC2(state->check, hold);
|
---|
| 723 | INITBITS();
|
---|
| 724 | state->mode = TIME;
|
---|
| 725 | case TIME:
|
---|
| 726 | NEEDBITS(32);
|
---|
| 727 | if (state->head != Z_NULL)
|
---|
| 728 | state->head->time = hold;
|
---|
| 729 | if ((state->flags & 0x0200) && (state->wrap & 4))
|
---|
| 730 | CRC4(state->check, hold);
|
---|
| 731 | INITBITS();
|
---|
| 732 | state->mode = OS;
|
---|
| 733 | case OS:
|
---|
| 734 | NEEDBITS(16);
|
---|
| 735 | if (state->head != Z_NULL) {
|
---|
| 736 | state->head->xflags = (int)(hold & 0xff);
|
---|
| 737 | state->head->os = (int)(hold >> 8);
|
---|
| 738 | }
|
---|
| 739 | if ((state->flags & 0x0200) && (state->wrap & 4))
|
---|
| 740 | CRC2(state->check, hold);
|
---|
| 741 | INITBITS();
|
---|
| 742 | state->mode = EXLEN;
|
---|
| 743 | case EXLEN:
|
---|
| 744 | if (state->flags & 0x0400) {
|
---|
| 745 | NEEDBITS(16);
|
---|
| 746 | state->length = (unsigned)(hold);
|
---|
| 747 | if (state->head != Z_NULL)
|
---|
| 748 | state->head->extra_len = (unsigned)hold;
|
---|
| 749 | if ((state->flags & 0x0200) && (state->wrap & 4))
|
---|
| 750 | CRC2(state->check, hold);
|
---|
| 751 | INITBITS();
|
---|
| 752 | }
|
---|
| 753 | else if (state->head != Z_NULL)
|
---|
| 754 | state->head->extra = Z_NULL;
|
---|
| 755 | state->mode = EXTRA;
|
---|
| 756 | case EXTRA:
|
---|
| 757 | if (state->flags & 0x0400) {
|
---|
| 758 | copy = state->length;
|
---|
| 759 | if (copy > have) copy = have;
|
---|
| 760 | if (copy) {
|
---|
| 761 | if (state->head != Z_NULL &&
|
---|
| 762 | state->head->extra != Z_NULL) {
|
---|
| 763 | len = state->head->extra_len - state->length;
|
---|
| 764 | zmemcpy(state->head->extra + len, next,
|
---|
| 765 | len + copy > state->head->extra_max ?
|
---|
| 766 | state->head->extra_max - len : copy);
|
---|
| 767 | }
|
---|
| 768 | if ((state->flags & 0x0200) && (state->wrap & 4))
|
---|
| 769 | state->check = crc32(state->check, next, copy);
|
---|
| 770 | have -= copy;
|
---|
| 771 | next += copy;
|
---|
| 772 | state->length -= copy;
|
---|
| 773 | }
|
---|
| 774 | if (state->length) goto inf_leave;
|
---|
| 775 | }
|
---|
| 776 | state->length = 0;
|
---|
| 777 | state->mode = NAME;
|
---|
| 778 | case NAME:
|
---|
| 779 | if (state->flags & 0x0800) {
|
---|
| 780 | if (have == 0) goto inf_leave;
|
---|
| 781 | copy = 0;
|
---|
| 782 | do {
|
---|
| 783 | len = (unsigned)(next[copy++]);
|
---|
| 784 | if (state->head != Z_NULL &&
|
---|
| 785 | state->head->name != Z_NULL &&
|
---|
| 786 | state->length < state->head->name_max)
|
---|
| 787 | state->head->name[state->length++] = (Bytef)len;
|
---|
| 788 | } while (len && copy < have);
|
---|
| 789 | if ((state->flags & 0x0200) && (state->wrap & 4))
|
---|
| 790 | state->check = crc32(state->check, next, copy);
|
---|
| 791 | have -= copy;
|
---|
| 792 | next += copy;
|
---|
| 793 | if (len) goto inf_leave;
|
---|
| 794 | }
|
---|
| 795 | else if (state->head != Z_NULL)
|
---|
| 796 | state->head->name = Z_NULL;
|
---|
| 797 | state->length = 0;
|
---|
| 798 | state->mode = COMMENT;
|
---|
| 799 | case COMMENT:
|
---|
| 800 | if (state->flags & 0x1000) {
|
---|
| 801 | if (have == 0) goto inf_leave;
|
---|
| 802 | copy = 0;
|
---|
| 803 | do {
|
---|
| 804 | len = (unsigned)(next[copy++]);
|
---|
| 805 | if (state->head != Z_NULL &&
|
---|
| 806 | state->head->comment != Z_NULL &&
|
---|
| 807 | state->length < state->head->comm_max)
|
---|
| 808 | state->head->comment[state->length++] = (Bytef)len;
|
---|
| 809 | } while (len && copy < have);
|
---|
| 810 | if ((state->flags & 0x0200) && (state->wrap & 4))
|
---|
| 811 | state->check = crc32(state->check, next, copy);
|
---|
| 812 | have -= copy;
|
---|
| 813 | next += copy;
|
---|
| 814 | if (len) goto inf_leave;
|
---|
| 815 | }
|
---|
| 816 | else if (state->head != Z_NULL)
|
---|
| 817 | state->head->comment = Z_NULL;
|
---|
| 818 | state->mode = HCRC;
|
---|
| 819 | case HCRC:
|
---|
| 820 | if (state->flags & 0x0200) {
|
---|
| 821 | NEEDBITS(16);
|
---|
| 822 | if ((state->wrap & 4) && hold != (state->check & 0xffff)) {
|
---|
| 823 | strm->msg = (char *)"header crc mismatch";
|
---|
| 824 | state->mode = BAD;
|
---|
| 825 | break;
|
---|
| 826 | }
|
---|
| 827 | INITBITS();
|
---|
| 828 | }
|
---|
| 829 | if (state->head != Z_NULL) {
|
---|
| 830 | state->head->hcrc = (int)((state->flags >> 9) & 1);
|
---|
| 831 | state->head->done = 1;
|
---|
| 832 | }
|
---|
| 833 | strm->adler = state->check = crc32(0L, Z_NULL, 0);
|
---|
| 834 | state->mode = TYPE;
|
---|
| 835 | break;
|
---|
| 836 | #endif
|
---|
| 837 | case DICTID:
|
---|
| 838 | NEEDBITS(32);
|
---|
| 839 | strm->adler = state->check = ZSWAP32(hold);
|
---|
| 840 | INITBITS();
|
---|
| 841 | state->mode = DICT;
|
---|
| 842 | case DICT:
|
---|
| 843 | if (state->havedict == 0) {
|
---|
| 844 | RESTORE();
|
---|
| 845 | return Z_NEED_DICT;
|
---|
| 846 | }
|
---|
| 847 | strm->adler = state->check = adler32(0L, Z_NULL, 0);
|
---|
| 848 | state->mode = TYPE;
|
---|
| 849 | case TYPE:
|
---|
| 850 | if (flush == Z_BLOCK || flush == Z_TREES) goto inf_leave;
|
---|
| 851 | case TYPEDO:
|
---|
| 852 | if (state->last) {
|
---|
| 853 | BYTEBITS();
|
---|
| 854 | state->mode = CHECK;
|
---|
| 855 | break;
|
---|
| 856 | }
|
---|
| 857 | NEEDBITS(3);
|
---|
| 858 | state->last = BITS(1);
|
---|
| 859 | DROPBITS(1);
|
---|
| 860 | switch (BITS(2)) {
|
---|
| 861 | case 0: /* stored block */
|
---|
| 862 | Tracev((stderr, "inflate: stored block%s\n",
|
---|
| 863 | state->last ? " (last)" : ""));
|
---|
| 864 | state->mode = STORED;
|
---|
| 865 | break;
|
---|
| 866 | case 1: /* fixed block */
|
---|
| 867 | fixedtables(state);
|
---|
| 868 | Tracev((stderr, "inflate: fixed codes block%s\n",
|
---|
| 869 | state->last ? " (last)" : ""));
|
---|
| 870 | state->mode = LEN_; /* decode codes */
|
---|
| 871 | if (flush == Z_TREES) {
|
---|
| 872 | DROPBITS(2);
|
---|
| 873 | goto inf_leave;
|
---|
| 874 | }
|
---|
| 875 | break;
|
---|
| 876 | case 2: /* dynamic block */
|
---|
| 877 | Tracev((stderr, "inflate: dynamic codes block%s\n",
|
---|
| 878 | state->last ? " (last)" : ""));
|
---|
| 879 | state->mode = TABLE;
|
---|
| 880 | break;
|
---|
| 881 | case 3:
|
---|
| 882 | strm->msg = (char *)"invalid block type";
|
---|
| 883 | state->mode = BAD;
|
---|
| 884 | }
|
---|
| 885 | DROPBITS(2);
|
---|
| 886 | break;
|
---|
| 887 | case STORED:
|
---|
| 888 | BYTEBITS(); /* go to byte boundary */
|
---|
| 889 | NEEDBITS(32);
|
---|
| 890 | if ((hold & 0xffff) != ((hold >> 16) ^ 0xffff)) {
|
---|
| 891 | strm->msg = (char *)"invalid stored block lengths";
|
---|
| 892 | state->mode = BAD;
|
---|
| 893 | break;
|
---|
| 894 | }
|
---|
| 895 | state->length = (unsigned)hold & 0xffff;
|
---|
| 896 | Tracev((stderr, "inflate: stored length %u\n",
|
---|
| 897 | state->length));
|
---|
| 898 | INITBITS();
|
---|
| 899 | state->mode = COPY_;
|
---|
| 900 | if (flush == Z_TREES) goto inf_leave;
|
---|
| 901 | case COPY_:
|
---|
| 902 | state->mode = COPY;
|
---|
| 903 | case COPY:
|
---|
| 904 | copy = state->length;
|
---|
| 905 | if (copy) {
|
---|
| 906 | if (copy > have) copy = have;
|
---|
| 907 | if (copy > left) copy = left;
|
---|
| 908 | if (copy == 0) goto inf_leave;
|
---|
| 909 | zmemcpy(put, next, copy);
|
---|
| 910 | have -= copy;
|
---|
| 911 | next += copy;
|
---|
| 912 | left -= copy;
|
---|
| 913 | put += copy;
|
---|
| 914 | state->length -= copy;
|
---|
| 915 | break;
|
---|
| 916 | }
|
---|
| 917 | Tracev((stderr, "inflate: stored end\n"));
|
---|
| 918 | state->mode = TYPE;
|
---|
| 919 | break;
|
---|
| 920 | case TABLE:
|
---|
| 921 | NEEDBITS(14);
|
---|
| 922 | state->nlen = BITS(5) + 257;
|
---|
| 923 | DROPBITS(5);
|
---|
| 924 | state->ndist = BITS(5) + 1;
|
---|
| 925 | DROPBITS(5);
|
---|
| 926 | state->ncode = BITS(4) + 4;
|
---|
| 927 | DROPBITS(4);
|
---|
| 928 | #ifndef PKZIP_BUG_WORKAROUND
|
---|
| 929 | if (state->nlen > 286 || state->ndist > 30) {
|
---|
| 930 | strm->msg = (char *)"too many length or distance symbols";
|
---|
| 931 | state->mode = BAD;
|
---|
| 932 | break;
|
---|
| 933 | }
|
---|
| 934 | #endif
|
---|
| 935 | Tracev((stderr, "inflate: table sizes ok\n"));
|
---|
| 936 | state->have = 0;
|
---|
| 937 | state->mode = LENLENS;
|
---|
| 938 | case LENLENS:
|
---|
| 939 | while (state->have < state->ncode) {
|
---|
| 940 | NEEDBITS(3);
|
---|
| 941 | state->lens[order[state->have++]] = (unsigned short)BITS(3);
|
---|
| 942 | DROPBITS(3);
|
---|
| 943 | }
|
---|
| 944 | while (state->have < 19)
|
---|
| 945 | state->lens[order[state->have++]] = 0;
|
---|
| 946 | state->next = state->codes;
|
---|
| 947 | state->lencode = (const code FAR *)(state->next);
|
---|
| 948 | state->lenbits = 7;
|
---|
| 949 | ret = inflate_table(CODES, state->lens, 19, &(state->next),
|
---|
| 950 | &(state->lenbits), state->work);
|
---|
| 951 | if (ret) {
|
---|
| 952 | strm->msg = (char *)"invalid code lengths set";
|
---|
| 953 | state->mode = BAD;
|
---|
| 954 | break;
|
---|
| 955 | }
|
---|
| 956 | Tracev((stderr, "inflate: code lengths ok\n"));
|
---|
| 957 | state->have = 0;
|
---|
| 958 | state->mode = CODELENS;
|
---|
| 959 | case CODELENS:
|
---|
| 960 | while (state->have < state->nlen + state->ndist) {
|
---|
| 961 | for (;;) {
|
---|
| 962 | here = state->lencode[BITS(state->lenbits)];
|
---|
| 963 | if ((unsigned)(here.bits) <= bits) break;
|
---|
| 964 | PULLBYTE();
|
---|
| 965 | }
|
---|
| 966 | if (here.val < 16) {
|
---|
| 967 | DROPBITS(here.bits);
|
---|
| 968 | state->lens[state->have++] = here.val;
|
---|
| 969 | }
|
---|
| 970 | else {
|
---|
| 971 | if (here.val == 16) {
|
---|
| 972 | NEEDBITS(here.bits + 2);
|
---|
| 973 | DROPBITS(here.bits);
|
---|
| 974 | if (state->have == 0) {
|
---|
| 975 | strm->msg = (char *)"invalid bit length repeat";
|
---|
| 976 | state->mode = BAD;
|
---|
| 977 | break;
|
---|
| 978 | }
|
---|
| 979 | len = state->lens[state->have - 1];
|
---|
| 980 | copy = 3 + BITS(2);
|
---|
| 981 | DROPBITS(2);
|
---|
| 982 | }
|
---|
| 983 | else if (here.val == 17) {
|
---|
| 984 | NEEDBITS(here.bits + 3);
|
---|
| 985 | DROPBITS(here.bits);
|
---|
| 986 | len = 0;
|
---|
| 987 | copy = 3 + BITS(3);
|
---|
| 988 | DROPBITS(3);
|
---|
| 989 | }
|
---|
| 990 | else {
|
---|
| 991 | NEEDBITS(here.bits + 7);
|
---|
| 992 | DROPBITS(here.bits);
|
---|
| 993 | len = 0;
|
---|
| 994 | copy = 11 + BITS(7);
|
---|
| 995 | DROPBITS(7);
|
---|
| 996 | }
|
---|
| 997 | if (state->have + copy > state->nlen + state->ndist) {
|
---|
| 998 | strm->msg = (char *)"invalid bit length repeat";
|
---|
| 999 | state->mode = BAD;
|
---|
| 1000 | break;
|
---|
| 1001 | }
|
---|
| 1002 | while (copy--)
|
---|
| 1003 | state->lens[state->have++] = (unsigned short)len;
|
---|
| 1004 | }
|
---|
| 1005 | }
|
---|
| 1006 |
|
---|
| 1007 | /* handle error breaks in while */
|
---|
| 1008 | if (state->mode == BAD) break;
|
---|
| 1009 |
|
---|
| 1010 | /* check for end-of-block code (better have one) */
|
---|
| 1011 | if (state->lens[256] == 0) {
|
---|
| 1012 | strm->msg = (char *)"invalid code -- missing end-of-block";
|
---|
| 1013 | state->mode = BAD;
|
---|
| 1014 | break;
|
---|
| 1015 | }
|
---|
| 1016 |
|
---|
| 1017 | /* build code tables -- note: do not change the lenbits or distbits
|
---|
| 1018 | values here (9 and 6) without reading the comments in inftrees.h
|
---|
| 1019 | concerning the ENOUGH constants, which depend on those values */
|
---|
| 1020 | state->next = state->codes;
|
---|
| 1021 | state->lencode = (const code FAR *)(state->next);
|
---|
| 1022 | state->lenbits = 9;
|
---|
| 1023 | ret = inflate_table(LENS, state->lens, state->nlen, &(state->next),
|
---|
| 1024 | &(state->lenbits), state->work);
|
---|
| 1025 | if (ret) {
|
---|
| 1026 | strm->msg = (char *)"invalid literal/lengths set";
|
---|
| 1027 | state->mode = BAD;
|
---|
| 1028 | break;
|
---|
| 1029 | }
|
---|
| 1030 | state->distcode = (const code FAR *)(state->next);
|
---|
| 1031 | state->distbits = 6;
|
---|
| 1032 | ret = inflate_table(DISTS, state->lens + state->nlen, state->ndist,
|
---|
| 1033 | &(state->next), &(state->distbits), state->work);
|
---|
| 1034 | if (ret) {
|
---|
| 1035 | strm->msg = (char *)"invalid distances set";
|
---|
| 1036 | state->mode = BAD;
|
---|
| 1037 | break;
|
---|
| 1038 | }
|
---|
| 1039 | Tracev((stderr, "inflate: codes ok\n"));
|
---|
| 1040 | state->mode = LEN_;
|
---|
| 1041 | if (flush == Z_TREES) goto inf_leave;
|
---|
| 1042 | case LEN_:
|
---|
| 1043 | state->mode = LEN;
|
---|
| 1044 | case LEN:
|
---|
| 1045 | if (have >= 6 && left >= 258) {
|
---|
| 1046 | RESTORE();
|
---|
| 1047 | inflate_fast(strm, out);
|
---|
| 1048 | LOAD();
|
---|
| 1049 | if (state->mode == TYPE)
|
---|
| 1050 | state->back = -1;
|
---|
| 1051 | break;
|
---|
| 1052 | }
|
---|
| 1053 | state->back = 0;
|
---|
| 1054 | for (;;) {
|
---|
| 1055 | here = state->lencode[BITS(state->lenbits)];
|
---|
| 1056 | if ((unsigned)(here.bits) <= bits) break;
|
---|
| 1057 | PULLBYTE();
|
---|
| 1058 | }
|
---|
| 1059 | if (here.op && (here.op & 0xf0) == 0) {
|
---|
| 1060 | last = here;
|
---|
| 1061 | for (;;) {
|
---|
| 1062 | here = state->lencode[last.val +
|
---|
| 1063 | (BITS(last.bits + last.op) >> last.bits)];
|
---|
| 1064 | if ((unsigned)(last.bits + here.bits) <= bits) break;
|
---|
| 1065 | PULLBYTE();
|
---|
| 1066 | }
|
---|
| 1067 | DROPBITS(last.bits);
|
---|
| 1068 | state->back += last.bits;
|
---|
| 1069 | }
|
---|
| 1070 | DROPBITS(here.bits);
|
---|
| 1071 | state->back += here.bits;
|
---|
| 1072 | state->length = (unsigned)here.val;
|
---|
| 1073 | if ((int)(here.op) == 0) {
|
---|
| 1074 | Tracevv((stderr, here.val >= 0x20 && here.val < 0x7f ?
|
---|
| 1075 | "inflate: literal '%c'\n" :
|
---|
| 1076 | "inflate: literal 0x%02x\n", here.val));
|
---|
| 1077 | state->mode = LIT;
|
---|
| 1078 | break;
|
---|
| 1079 | }
|
---|
| 1080 | if (here.op & 32) {
|
---|
| 1081 | Tracevv((stderr, "inflate: end of block\n"));
|
---|
| 1082 | state->back = -1;
|
---|
| 1083 | state->mode = TYPE;
|
---|
| 1084 | break;
|
---|
| 1085 | }
|
---|
| 1086 | if (here.op & 64) {
|
---|
| 1087 | strm->msg = (char *)"invalid literal/length code";
|
---|
| 1088 | state->mode = BAD;
|
---|
| 1089 | break;
|
---|
| 1090 | }
|
---|
| 1091 | state->extra = (unsigned)(here.op) & 15;
|
---|
| 1092 | state->mode = LENEXT;
|
---|
| 1093 | case LENEXT:
|
---|
| 1094 | if (state->extra) {
|
---|
| 1095 | NEEDBITS(state->extra);
|
---|
| 1096 | state->length += BITS(state->extra);
|
---|
| 1097 | DROPBITS(state->extra);
|
---|
| 1098 | state->back += state->extra;
|
---|
| 1099 | }
|
---|
| 1100 | Tracevv((stderr, "inflate: length %u\n", state->length));
|
---|
| 1101 | state->was = state->length;
|
---|
| 1102 | state->mode = DIST;
|
---|
| 1103 | case DIST:
|
---|
| 1104 | for (;;) {
|
---|
| 1105 | here = state->distcode[BITS(state->distbits)];
|
---|
| 1106 | if ((unsigned)(here.bits) <= bits) break;
|
---|
| 1107 | PULLBYTE();
|
---|
| 1108 | }
|
---|
| 1109 | if ((here.op & 0xf0) == 0) {
|
---|
| 1110 | last = here;
|
---|
| 1111 | for (;;) {
|
---|
| 1112 | here = state->distcode[last.val +
|
---|
| 1113 | (BITS(last.bits + last.op) >> last.bits)];
|
---|
| 1114 | if ((unsigned)(last.bits + here.bits) <= bits) break;
|
---|
| 1115 | PULLBYTE();
|
---|
| 1116 | }
|
---|
| 1117 | DROPBITS(last.bits);
|
---|
| 1118 | state->back += last.bits;
|
---|
| 1119 | }
|
---|
| 1120 | DROPBITS(here.bits);
|
---|
| 1121 | state->back += here.bits;
|
---|
| 1122 | if (here.op & 64) {
|
---|
| 1123 | strm->msg = (char *)"invalid distance code";
|
---|
| 1124 | state->mode = BAD;
|
---|
| 1125 | break;
|
---|
| 1126 | }
|
---|
| 1127 | state->offset = (unsigned)here.val;
|
---|
| 1128 | state->extra = (unsigned)(here.op) & 15;
|
---|
| 1129 | state->mode = DISTEXT;
|
---|
| 1130 | case DISTEXT:
|
---|
| 1131 | if (state->extra) {
|
---|
| 1132 | NEEDBITS(state->extra);
|
---|
| 1133 | state->offset += BITS(state->extra);
|
---|
| 1134 | DROPBITS(state->extra);
|
---|
| 1135 | state->back += state->extra;
|
---|
| 1136 | }
|
---|
| 1137 | #ifdef INFLATE_STRICT
|
---|
| 1138 | if (state->offset > state->dmax) {
|
---|
| 1139 | strm->msg = (char *)"invalid distance too far back";
|
---|
| 1140 | state->mode = BAD;
|
---|
| 1141 | break;
|
---|
| 1142 | }
|
---|
| 1143 | #endif
|
---|
| 1144 | Tracevv((stderr, "inflate: distance %u\n", state->offset));
|
---|
| 1145 | state->mode = MATCH;
|
---|
| 1146 | case MATCH:
|
---|
| 1147 | if (left == 0) goto inf_leave;
|
---|
| 1148 | copy = out - left;
|
---|
| 1149 | if (state->offset > copy) { /* copy from window */
|
---|
| 1150 | copy = state->offset - copy;
|
---|
| 1151 | if (copy > state->whave) {
|
---|
| 1152 | if (state->sane) {
|
---|
| 1153 | strm->msg = (char *)"invalid distance too far back";
|
---|
| 1154 | state->mode = BAD;
|
---|
| 1155 | break;
|
---|
| 1156 | }
|
---|
| 1157 | #ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR
|
---|
| 1158 | Trace((stderr, "inflate.c too far\n"));
|
---|
| 1159 | copy -= state->whave;
|
---|
| 1160 | if (copy > state->length) copy = state->length;
|
---|
| 1161 | if (copy > left) copy = left;
|
---|
| 1162 | left -= copy;
|
---|
| 1163 | state->length -= copy;
|
---|
| 1164 | do {
|
---|
| 1165 | *put++ = 0;
|
---|
| 1166 | } while (--copy);
|
---|
| 1167 | if (state->length == 0) state->mode = LEN;
|
---|
| 1168 | break;
|
---|
| 1169 | #endif
|
---|
| 1170 | }
|
---|
| 1171 | if (copy > state->wnext) {
|
---|
| 1172 | copy -= state->wnext;
|
---|
| 1173 | from = state->window + (state->wsize - copy);
|
---|
| 1174 | }
|
---|
| 1175 | else
|
---|
| 1176 | from = state->window + (state->wnext - copy);
|
---|
| 1177 | if (copy > state->length) copy = state->length;
|
---|
| 1178 | }
|
---|
| 1179 | else { /* copy from output */
|
---|
| 1180 | from = put - state->offset;
|
---|
| 1181 | copy = state->length;
|
---|
| 1182 | }
|
---|
| 1183 | if (copy > left) copy = left;
|
---|
| 1184 | left -= copy;
|
---|
| 1185 | state->length -= copy;
|
---|
| 1186 | do {
|
---|
| 1187 | *put++ = *from++;
|
---|
| 1188 | } while (--copy);
|
---|
| 1189 | if (state->length == 0) state->mode = LEN;
|
---|
| 1190 | break;
|
---|
| 1191 | case LIT:
|
---|
| 1192 | if (left == 0) goto inf_leave;
|
---|
| 1193 | *put++ = (unsigned char)(state->length);
|
---|
| 1194 | left--;
|
---|
| 1195 | state->mode = LEN;
|
---|
| 1196 | break;
|
---|
| 1197 | case CHECK:
|
---|
| 1198 | if (state->wrap) {
|
---|
| 1199 | NEEDBITS(32);
|
---|
| 1200 | out -= left;
|
---|
| 1201 | strm->total_out += out;
|
---|
| 1202 | state->total += out;
|
---|
| 1203 | if ((state->wrap & 4) && out)
|
---|
| 1204 | strm->adler = state->check =
|
---|
| 1205 | UPDATE(state->check, put - out, out);
|
---|
| 1206 | out = left;
|
---|
| 1207 | if ((state->wrap & 4) && (
|
---|
| 1208 | #ifdef GUNZIP
|
---|
| 1209 | state->flags ? hold :
|
---|
| 1210 | #endif
|
---|
| 1211 | ZSWAP32(hold)) != state->check) {
|
---|
| 1212 | strm->msg = (char *)"incorrect data check";
|
---|
| 1213 | state->mode = BAD;
|
---|
| 1214 | break;
|
---|
| 1215 | }
|
---|
| 1216 | INITBITS();
|
---|
| 1217 | Tracev((stderr, "inflate: check matches trailer\n"));
|
---|
| 1218 | }
|
---|
| 1219 | #ifdef GUNZIP
|
---|
| 1220 | state->mode = LENGTH;
|
---|
| 1221 | case LENGTH:
|
---|
| 1222 | if (state->wrap && state->flags) {
|
---|
| 1223 | NEEDBITS(32);
|
---|
| 1224 | if (hold != (state->total & 0xffffffffUL)) {
|
---|
| 1225 | strm->msg = (char *)"incorrect length check";
|
---|
| 1226 | state->mode = BAD;
|
---|
| 1227 | break;
|
---|
| 1228 | }
|
---|
| 1229 | INITBITS();
|
---|
| 1230 | Tracev((stderr, "inflate: length matches trailer\n"));
|
---|
| 1231 | }
|
---|
| 1232 | #endif
|
---|
| 1233 | state->mode = DONE;
|
---|
| 1234 | case DONE:
|
---|
| 1235 | ret = Z_STREAM_END;
|
---|
| 1236 | goto inf_leave;
|
---|
| 1237 | case BAD:
|
---|
| 1238 | ret = Z_DATA_ERROR;
|
---|
| 1239 | goto inf_leave;
|
---|
| 1240 | case MEM:
|
---|
| 1241 | return Z_MEM_ERROR;
|
---|
| 1242 | case SYNC:
|
---|
| 1243 | default:
|
---|
| 1244 | return Z_STREAM_ERROR;
|
---|
| 1245 | }
|
---|
| 1246 |
|
---|
| 1247 | /*
|
---|
| 1248 | Return from inflate(), updating the total counts and the check value.
|
---|
| 1249 | If there was no progress during the inflate() call, return a buffer
|
---|
| 1250 | error. Call updatewindow() to create and/or update the window state.
|
---|
| 1251 | Note: a memory error from inflate() is non-recoverable.
|
---|
| 1252 | */
|
---|
| 1253 | inf_leave:
|
---|
| 1254 | RESTORE();
|
---|
| 1255 | if (state->wsize || (out != strm->avail_out && state->mode < BAD &&
|
---|
| 1256 | (state->mode < CHECK || flush != Z_FINISH)))
|
---|
| 1257 | if (updatewindow(strm, strm->next_out, out - strm->avail_out)) {
|
---|
| 1258 | state->mode = MEM;
|
---|
| 1259 | return Z_MEM_ERROR;
|
---|
| 1260 | }
|
---|
| 1261 | in -= strm->avail_in;
|
---|
| 1262 | out -= strm->avail_out;
|
---|
| 1263 | strm->total_in += in;
|
---|
| 1264 | strm->total_out += out;
|
---|
| 1265 | state->total += out;
|
---|
| 1266 | if ((state->wrap & 4) && out)
|
---|
| 1267 | strm->adler = state->check =
|
---|
| 1268 | UPDATE(state->check, strm->next_out - out, out);
|
---|
| 1269 | strm->data_type = (int)state->bits + (state->last ? 64 : 0) +
|
---|
| 1270 | (state->mode == TYPE ? 128 : 0) +
|
---|
| 1271 | (state->mode == LEN_ || state->mode == COPY_ ? 256 : 0);
|
---|
| 1272 | if (((in == 0 && out == 0) || flush == Z_FINISH) && ret == Z_OK)
|
---|
| 1273 | ret = Z_BUF_ERROR;
|
---|
| 1274 | return ret;
|
---|
| 1275 | }
|
---|
| 1276 |
|
---|
| 1277 | int ZEXPORT inflateEnd(strm)
|
---|
| 1278 | z_streamp strm;
|
---|
| 1279 | {
|
---|
| 1280 | struct inflate_state FAR *state;
|
---|
| 1281 | if (inflateStateCheck(strm))
|
---|
| 1282 | return Z_STREAM_ERROR;
|
---|
| 1283 | state = (struct inflate_state FAR *)strm->state;
|
---|
| 1284 | if (state->window != Z_NULL) ZFREE(strm, state->window);
|
---|
| 1285 | ZFREE(strm, strm->state);
|
---|
| 1286 | strm->state = Z_NULL;
|
---|
| 1287 | Tracev((stderr, "inflate: end\n"));
|
---|
| 1288 | return Z_OK;
|
---|
| 1289 | }
|
---|
| 1290 |
|
---|
| 1291 | int ZEXPORT inflateGetDictionary(strm, dictionary, dictLength)
|
---|
| 1292 | z_streamp strm;
|
---|
| 1293 | Bytef *dictionary;
|
---|
| 1294 | uInt *dictLength;
|
---|
| 1295 | {
|
---|
| 1296 | struct inflate_state FAR *state;
|
---|
| 1297 |
|
---|
| 1298 | /* check state */
|
---|
| 1299 | if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
|
---|
| 1300 | state = (struct inflate_state FAR *)strm->state;
|
---|
| 1301 |
|
---|
| 1302 | /* copy dictionary */
|
---|
| 1303 | if (state->whave && dictionary != Z_NULL) {
|
---|
| 1304 | zmemcpy(dictionary, state->window + state->wnext,
|
---|
| 1305 | state->whave - state->wnext);
|
---|
| 1306 | zmemcpy(dictionary + state->whave - state->wnext,
|
---|
| 1307 | state->window, state->wnext);
|
---|
| 1308 | }
|
---|
| 1309 | if (dictLength != Z_NULL)
|
---|
| 1310 | *dictLength = state->whave;
|
---|
| 1311 | return Z_OK;
|
---|
| 1312 | }
|
---|
| 1313 |
|
---|
| 1314 | int ZEXPORT inflateSetDictionary(strm, dictionary, dictLength)
|
---|
| 1315 | z_streamp strm;
|
---|
| 1316 | const Bytef *dictionary;
|
---|
| 1317 | uInt dictLength;
|
---|
| 1318 | {
|
---|
| 1319 | struct inflate_state FAR *state;
|
---|
| 1320 | unsigned long dictid;
|
---|
| 1321 | int ret;
|
---|
| 1322 |
|
---|
| 1323 | /* check state */
|
---|
| 1324 | if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
|
---|
| 1325 | state = (struct inflate_state FAR *)strm->state;
|
---|
| 1326 | if (state->wrap != 0 && state->mode != DICT)
|
---|
| 1327 | return Z_STREAM_ERROR;
|
---|
| 1328 |
|
---|
| 1329 | /* check for correct dictionary identifier */
|
---|
| 1330 | if (state->mode == DICT) {
|
---|
| 1331 | dictid = adler32(0L, Z_NULL, 0);
|
---|
| 1332 | dictid = adler32(dictid, dictionary, dictLength);
|
---|
| 1333 | if (dictid != state->check)
|
---|
| 1334 | return Z_DATA_ERROR;
|
---|
| 1335 | }
|
---|
| 1336 |
|
---|
| 1337 | /* copy dictionary to window using updatewindow(), which will amend the
|
---|
| 1338 | existing dictionary if appropriate */
|
---|
| 1339 | ret = updatewindow(strm, dictionary + dictLength, dictLength);
|
---|
| 1340 | if (ret) {
|
---|
| 1341 | state->mode = MEM;
|
---|
| 1342 | return Z_MEM_ERROR;
|
---|
| 1343 | }
|
---|
| 1344 | state->havedict = 1;
|
---|
| 1345 | Tracev((stderr, "inflate: dictionary set\n"));
|
---|
| 1346 | return Z_OK;
|
---|
| 1347 | }
|
---|
| 1348 |
|
---|
| 1349 | int ZEXPORT inflateGetHeader(strm, head)
|
---|
| 1350 | z_streamp strm;
|
---|
| 1351 | gz_headerp head;
|
---|
| 1352 | {
|
---|
| 1353 | struct inflate_state FAR *state;
|
---|
| 1354 |
|
---|
| 1355 | /* check state */
|
---|
| 1356 | if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
|
---|
| 1357 | state = (struct inflate_state FAR *)strm->state;
|
---|
| 1358 | if ((state->wrap & 2) == 0) return Z_STREAM_ERROR;
|
---|
| 1359 |
|
---|
| 1360 | /* save header structure */
|
---|
| 1361 | state->head = head;
|
---|
| 1362 | head->done = 0;
|
---|
| 1363 | return Z_OK;
|
---|
| 1364 | }
|
---|
| 1365 |
|
---|
| 1366 | /*
|
---|
| 1367 | Search buf[0..len-1] for the pattern: 0, 0, 0xff, 0xff. Return when found
|
---|
| 1368 | or when out of input. When called, *have is the number of pattern bytes
|
---|
| 1369 | found in order so far, in 0..3. On return *have is updated to the new
|
---|
| 1370 | state. If on return *have equals four, then the pattern was found and the
|
---|
| 1371 | return value is how many bytes were read including the last byte of the
|
---|
| 1372 | pattern. If *have is less than four, then the pattern has not been found
|
---|
| 1373 | yet and the return value is len. In the latter case, syncsearch() can be
|
---|
| 1374 | called again with more data and the *have state. *have is initialized to
|
---|
| 1375 | zero for the first call.
|
---|
| 1376 | */
|
---|
| 1377 | local unsigned syncsearch(have, buf, len)
|
---|
| 1378 | unsigned FAR *have;
|
---|
| 1379 | const unsigned char FAR *buf;
|
---|
| 1380 | unsigned len;
|
---|
| 1381 | {
|
---|
| 1382 | unsigned got;
|
---|
| 1383 | unsigned next;
|
---|
| 1384 |
|
---|
| 1385 | got = *have;
|
---|
| 1386 | next = 0;
|
---|
| 1387 | while (next < len && got < 4) {
|
---|
| 1388 | if ((int)(buf[next]) == (got < 2 ? 0 : 0xff))
|
---|
| 1389 | got++;
|
---|
| 1390 | else if (buf[next])
|
---|
| 1391 | got = 0;
|
---|
| 1392 | else
|
---|
| 1393 | got = 4 - got;
|
---|
| 1394 | next++;
|
---|
| 1395 | }
|
---|
| 1396 | *have = got;
|
---|
| 1397 | return next;
|
---|
| 1398 | }
|
---|
| 1399 |
|
---|
| 1400 | int ZEXPORT inflateSync(strm)
|
---|
| 1401 | z_streamp strm;
|
---|
| 1402 | {
|
---|
| 1403 | unsigned len; /* number of bytes to look at or looked at */
|
---|
| 1404 | unsigned long in, out; /* temporary to save total_in and total_out */
|
---|
| 1405 | unsigned char buf[4]; /* to restore bit buffer to byte string */
|
---|
| 1406 | struct inflate_state FAR *state;
|
---|
| 1407 |
|
---|
| 1408 | /* check parameters */
|
---|
| 1409 | if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
|
---|
| 1410 | state = (struct inflate_state FAR *)strm->state;
|
---|
| 1411 | if (strm->avail_in == 0 && state->bits < 8) return Z_BUF_ERROR;
|
---|
| 1412 |
|
---|
| 1413 | /* if first time, start search in bit buffer */
|
---|
| 1414 | if (state->mode != SYNC) {
|
---|
| 1415 | state->mode = SYNC;
|
---|
| 1416 | state->hold <<= state->bits & 7;
|
---|
| 1417 | state->bits -= state->bits & 7;
|
---|
| 1418 | len = 0;
|
---|
| 1419 | while (state->bits >= 8) {
|
---|
| 1420 | buf[len++] = (unsigned char)(state->hold);
|
---|
| 1421 | state->hold >>= 8;
|
---|
| 1422 | state->bits -= 8;
|
---|
| 1423 | }
|
---|
| 1424 | state->have = 0;
|
---|
| 1425 | syncsearch(&(state->have), buf, len);
|
---|
| 1426 | }
|
---|
| 1427 |
|
---|
| 1428 | /* search available input */
|
---|
| 1429 | len = syncsearch(&(state->have), strm->next_in, strm->avail_in);
|
---|
| 1430 | strm->avail_in -= len;
|
---|
| 1431 | strm->next_in += len;
|
---|
| 1432 | strm->total_in += len;
|
---|
| 1433 |
|
---|
| 1434 | /* return no joy or set up to restart inflate() on a new block */
|
---|
| 1435 | if (state->have != 4) return Z_DATA_ERROR;
|
---|
| 1436 | in = strm->total_in; out = strm->total_out;
|
---|
| 1437 | inflateReset(strm);
|
---|
| 1438 | strm->total_in = in; strm->total_out = out;
|
---|
| 1439 | state->mode = TYPE;
|
---|
| 1440 | return Z_OK;
|
---|
| 1441 | }
|
---|
| 1442 |
|
---|
| 1443 | /*
|
---|
| 1444 | Returns true if inflate is currently at the end of a block generated by
|
---|
| 1445 | Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP
|
---|
| 1446 | implementation to provide an additional safety check. PPP uses
|
---|
| 1447 | Z_SYNC_FLUSH but removes the length bytes of the resulting empty stored
|
---|
| 1448 | block. When decompressing, PPP checks that at the end of input packet,
|
---|
| 1449 | inflate is waiting for these length bytes.
|
---|
| 1450 | */
|
---|
| 1451 | int ZEXPORT inflateSyncPoint(strm)
|
---|
| 1452 | z_streamp strm;
|
---|
| 1453 | {
|
---|
| 1454 | struct inflate_state FAR *state;
|
---|
| 1455 |
|
---|
| 1456 | if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
|
---|
| 1457 | state = (struct inflate_state FAR *)strm->state;
|
---|
| 1458 | return state->mode == STORED && state->bits == 0;
|
---|
| 1459 | }
|
---|
| 1460 |
|
---|
| 1461 | int ZEXPORT inflateCopy(dest, source)
|
---|
| 1462 | z_streamp dest;
|
---|
| 1463 | z_streamp source;
|
---|
| 1464 | {
|
---|
| 1465 | struct inflate_state FAR *state;
|
---|
| 1466 | struct inflate_state FAR *copy;
|
---|
| 1467 | unsigned char FAR *window;
|
---|
| 1468 | unsigned wsize;
|
---|
| 1469 |
|
---|
| 1470 | /* check input */
|
---|
| 1471 | if (inflateStateCheck(source) || dest == Z_NULL)
|
---|
| 1472 | return Z_STREAM_ERROR;
|
---|
| 1473 | state = (struct inflate_state FAR *)source->state;
|
---|
| 1474 |
|
---|
| 1475 | /* allocate space */
|
---|
| 1476 | copy = (struct inflate_state FAR *)
|
---|
| 1477 | ZALLOC(source, 1, sizeof(struct inflate_state));
|
---|
| 1478 | if (copy == Z_NULL) return Z_MEM_ERROR;
|
---|
| 1479 | window = Z_NULL;
|
---|
| 1480 | if (state->window != Z_NULL) {
|
---|
| 1481 | window = (unsigned char FAR *)
|
---|
| 1482 | ZALLOC(source, 1U << state->wbits, sizeof(unsigned char));
|
---|
| 1483 | if (window == Z_NULL) {
|
---|
| 1484 | ZFREE(source, copy);
|
---|
| 1485 | return Z_MEM_ERROR;
|
---|
| 1486 | }
|
---|
| 1487 | }
|
---|
| 1488 |
|
---|
| 1489 | /* copy state */
|
---|
| 1490 | zmemcpy((voidpf)dest, (voidpf)source, sizeof(z_stream));
|
---|
| 1491 | zmemcpy((voidpf)copy, (voidpf)state, sizeof(struct inflate_state));
|
---|
| 1492 | copy->strm = dest;
|
---|
| 1493 | if (state->lencode >= state->codes &&
|
---|
| 1494 | state->lencode <= state->codes + ENOUGH - 1) {
|
---|
| 1495 | copy->lencode = copy->codes + (state->lencode - state->codes);
|
---|
| 1496 | copy->distcode = copy->codes + (state->distcode - state->codes);
|
---|
| 1497 | }
|
---|
| 1498 | copy->next = copy->codes + (state->next - state->codes);
|
---|
| 1499 | if (window != Z_NULL) {
|
---|
| 1500 | wsize = 1U << state->wbits;
|
---|
| 1501 | zmemcpy(window, state->window, wsize);
|
---|
| 1502 | }
|
---|
| 1503 | copy->window = window;
|
---|
| 1504 | dest->state = (struct internal_state FAR *)copy;
|
---|
| 1505 | return Z_OK;
|
---|
| 1506 | }
|
---|
| 1507 |
|
---|
| 1508 | int ZEXPORT inflateUndermine(strm, subvert)
|
---|
| 1509 | z_streamp strm;
|
---|
| 1510 | int subvert;
|
---|
| 1511 | {
|
---|
| 1512 | struct inflate_state FAR *state;
|
---|
| 1513 |
|
---|
| 1514 | if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
|
---|
| 1515 | state = (struct inflate_state FAR *)strm->state;
|
---|
| 1516 | #ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR
|
---|
| 1517 | state->sane = !subvert;
|
---|
| 1518 | return Z_OK;
|
---|
| 1519 | #else
|
---|
| 1520 | (void)subvert;
|
---|
| 1521 | state->sane = 1;
|
---|
| 1522 | return Z_DATA_ERROR;
|
---|
| 1523 | #endif
|
---|
| 1524 | }
|
---|
| 1525 |
|
---|
| 1526 | int ZEXPORT inflateValidate(strm, check)
|
---|
| 1527 | z_streamp strm;
|
---|
| 1528 | int check;
|
---|
| 1529 | {
|
---|
| 1530 | struct inflate_state FAR *state;
|
---|
| 1531 |
|
---|
| 1532 | if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
|
---|
| 1533 | state = (struct inflate_state FAR *)strm->state;
|
---|
| 1534 | if (check)
|
---|
| 1535 | state->wrap |= 4;
|
---|
| 1536 | else
|
---|
| 1537 | state->wrap &= ~4;
|
---|
| 1538 | return Z_OK;
|
---|
| 1539 | }
|
---|
| 1540 |
|
---|
| 1541 | long ZEXPORT inflateMark(strm)
|
---|
| 1542 | z_streamp strm;
|
---|
| 1543 | {
|
---|
| 1544 | struct inflate_state FAR *state;
|
---|
| 1545 |
|
---|
| 1546 | if (inflateStateCheck(strm))
|
---|
| 1547 | return -(1L << 16);
|
---|
| 1548 | state = (struct inflate_state FAR *)strm->state;
|
---|
| 1549 | return (long)(((unsigned long)((long)state->back)) << 16) +
|
---|
| 1550 | (state->mode == COPY ? state->length :
|
---|
| 1551 | (state->mode == MATCH ? state->was - state->length : 0));
|
---|
| 1552 | }
|
---|
| 1553 |
|
---|
| 1554 | unsigned long ZEXPORT inflateCodesUsed(strm)
|
---|
| 1555 | z_streamp strm;
|
---|
| 1556 | {
|
---|
| 1557 | struct inflate_state FAR *state;
|
---|
| 1558 | if (inflateStateCheck(strm)) return (unsigned long)-1;
|
---|
| 1559 | state = (struct inflate_state FAR *)strm->state;
|
---|
| 1560 | return (unsigned long)(state->next - state->codes);
|
---|
| 1561 | }
|
---|