| 1 |
/* infback9.c -- inflate deflate64 data using a call-back interface |
| 2 |
* Copyright (C) 1995-2008 Mark Adler |
| 3 |
* For conditions of distribution and use, see copyright notice in zlib.h |
| 4 |
*/ |
| 5 |
|
| 6 |
#include "zutil.h" |
| 7 |
#include "infback9.h" |
| 8 |
#include "inftree9.h" |
| 9 |
#include "inflate9.h" |
| 10 |
|
| 11 |
#define WSIZE 65536UL |
| 12 |
|
| 13 |
/* |
| 14 |
strm provides memory allocation functions in zalloc and zfree, or |
| 15 |
Z_NULL to use the library memory allocation functions. |
| 16 |
|
| 17 |
window is a user-supplied window and output buffer that is 64K bytes. |
| 18 |
*/ |
| 19 |
int ZEXPORT inflateBack9Init_(strm, window, version, stream_size) |
| 20 |
z_stream FAR *strm; |
| 21 |
unsigned char FAR *window; |
| 22 |
const char *version; |
| 23 |
int stream_size; |
| 24 |
{ |
| 25 |
struct inflate_state FAR *state; |
| 26 |
|
| 27 |
if (version == Z_NULL || version[0] != ZLIB_VERSION[0] || |
| 28 |
stream_size != (int)(sizeof(z_stream))) |
| 29 |
return Z_VERSION_ERROR; |
| 30 |
if (strm == Z_NULL || window == Z_NULL) |
| 31 |
return Z_STREAM_ERROR; |
| 32 |
strm->msg = Z_NULL; /* in case we return an error */ |
| 33 |
if (strm->zalloc == (alloc_func)0) { |
| 34 |
strm->zalloc = zcalloc; |
| 35 |
strm->opaque = (voidpf)0; |
| 36 |
} |
| 37 |
if (strm->zfree == (free_func)0) strm->zfree = zcfree; |
| 38 |
state = (struct inflate_state FAR *)ZALLOC(strm, 1, |
| 39 |
sizeof(struct inflate_state)); |
| 40 |
if (state == Z_NULL) return Z_MEM_ERROR; |
| 41 |
Tracev((stderr, "inflate: allocated\n")); |
| 42 |
strm->state = (voidpf)state; |
| 43 |
state->window = window; |
| 44 |
return Z_OK; |
| 45 |
} |
| 46 |
|
| 47 |
/* |
| 48 |
Build and output length and distance decoding tables for fixed code |
| 49 |
decoding. |
| 50 |
*/ |
| 51 |
#ifdef MAKEFIXED |
| 52 |
#include <stdio.h> |
| 53 |
|
| 54 |
void makefixed9(void) |
| 55 |
{ |
| 56 |
unsigned sym, bits, low, size; |
| 57 |
code *next, *lenfix, *distfix; |
| 58 |
struct inflate_state state; |
| 59 |
code fixed[544]; |
| 60 |
|
| 61 |
/* literal/length table */ |
| 62 |
sym = 0; |
| 63 |
while (sym < 144) state.lens[sym++] = 8; |
| 64 |
while (sym < 256) state.lens[sym++] = 9; |
| 65 |
while (sym < 280) state.lens[sym++] = 7; |
| 66 |
while (sym < 288) state.lens[sym++] = 8; |
| 67 |
next = fixed; |
| 68 |
lenfix = next; |
| 69 |
bits = 9; |
| 70 |
inflate_table9(LENS, state.lens, 288, &(next), &(bits), state.work); |
| 71 |
|
| 72 |
/* distance table */ |
| 73 |
sym = 0; |
| 74 |
while (sym < 32) state.lens[sym++] = 5; |
| 75 |
distfix = next; |
| 76 |
bits = 5; |
| 77 |
inflate_table9(DISTS, state.lens, 32, &(next), &(bits), state.work); |
| 78 |
|
| 79 |
/* write tables */ |
| 80 |
puts(" /* inffix9.h -- table for decoding deflate64 fixed codes"); |
| 81 |
puts(" * Generated automatically by makefixed9()."); |
| 82 |
puts(" */"); |
| 83 |
puts(""); |
| 84 |
puts(" /* WARNING: this file should *not* be used by applications."); |
| 85 |
puts(" It is part of the implementation of this library and is"); |
| 86 |
puts(" subject to change. Applications should only use zlib.h."); |
| 87 |
puts(" */"); |
| 88 |
puts(""); |
| 89 |
size = 1U << 9; |
| 90 |
printf(" static const code lenfix[%u] = {", size); |
| 91 |
low = 0; |
| 92 |
for (;;) { |
| 93 |
if ((low % 6) == 0) printf("\n "); |
| 94 |
printf("{%u,%u,%d}", lenfix[low].op, lenfix[low].bits, |
| 95 |
lenfix[low].val); |
| 96 |
if (++low == size) break; |
| 97 |
putchar(','); |
| 98 |
} |
| 99 |
puts("\n };"); |
| 100 |
size = 1U << 5; |
| 101 |
printf("\n static const code distfix[%u] = {", size); |
| 102 |
low = 0; |
| 103 |
for (;;) { |
| 104 |
if ((low % 5) == 0) printf("\n "); |
| 105 |
printf("{%u,%u,%d}", distfix[low].op, distfix[low].bits, |
| 106 |
distfix[low].val); |
| 107 |
if (++low == size) break; |
| 108 |
putchar(','); |
| 109 |
} |
| 110 |
puts("\n };"); |
| 111 |
} |
| 112 |
#endif /* MAKEFIXED */ |
| 113 |
|
| 114 |
/* Macros for inflateBack(): */ |
| 115 |
|
| 116 |
/* Clear the input bit accumulator */ |
| 117 |
#define INITBITS() \ |
| 118 |
do { \ |
| 119 |
hold = 0; \ |
| 120 |
bits = 0; \ |
| 121 |
} while (0) |
| 122 |
|
| 123 |
/* Assure that some input is available. If input is requested, but denied, |
| 124 |
then return a Z_BUF_ERROR from inflateBack(). */ |
| 125 |
#define PULL() \ |
| 126 |
do { \ |
| 127 |
if (have == 0) { \ |
| 128 |
have = in(in_desc, &next); \ |
| 129 |
if (have == 0) { \ |
| 130 |
next = Z_NULL; \ |
| 131 |
ret = Z_BUF_ERROR; \ |
| 132 |
goto inf_leave; \ |
| 133 |
} \ |
| 134 |
} \ |
| 135 |
} while (0) |
| 136 |
|
| 137 |
/* Get a byte of input into the bit accumulator, or return from inflateBack() |
| 138 |
with an error if there is no input available. */ |
| 139 |
#define PULLBYTE() \ |
| 140 |
do { \ |
| 141 |
PULL(); \ |
| 142 |
have--; \ |
| 143 |
hold += (unsigned long)(*next++) << bits; \ |
| 144 |
bits += 8; \ |
| 145 |
} while (0) |
| 146 |
|
| 147 |
/* Assure that there are at least n bits in the bit accumulator. If there is |
| 148 |
not enough available input to do that, then return from inflateBack() with |
| 149 |
an error. */ |
| 150 |
#define NEEDBITS(n) \ |
| 151 |
do { \ |
| 152 |
while (bits < (unsigned)(n)) \ |
| 153 |
PULLBYTE(); \ |
| 154 |
} while (0) |
| 155 |
|
| 156 |
/* Return the low n bits of the bit accumulator (n <= 16) */ |
| 157 |
#define BITS(n) \ |
| 158 |
((unsigned)hold & ((1U << (n)) - 1)) |
| 159 |
|
| 160 |
/* Remove n bits from the bit accumulator */ |
| 161 |
#define DROPBITS(n) \ |
| 162 |
do { \ |
| 163 |
hold >>= (n); \ |
| 164 |
bits -= (unsigned)(n); \ |
| 165 |
} while (0) |
| 166 |
|
| 167 |
/* Remove zero to seven bits as needed to go to a byte boundary */ |
| 168 |
#define BYTEBITS() \ |
| 169 |
do { \ |
| 170 |
hold >>= bits & 7; \ |
| 171 |
bits -= bits & 7; \ |
| 172 |
} while (0) |
| 173 |
|
| 174 |
/* Assure that some output space is available, by writing out the window |
| 175 |
if it's full. If the write fails, return from inflateBack() with a |
| 176 |
Z_BUF_ERROR. */ |
| 177 |
#define ROOM() \ |
| 178 |
do { \ |
| 179 |
if (left == 0) { \ |
| 180 |
put = window; \ |
| 181 |
left = WSIZE; \ |
| 182 |
wrap = 1; \ |
| 183 |
if (out(out_desc, put, (unsigned)left)) { \ |
| 184 |
ret = Z_BUF_ERROR; \ |
| 185 |
goto inf_leave; \ |
| 186 |
} \ |
| 187 |
} \ |
| 188 |
} while (0) |
| 189 |
|
| 190 |
/* |
| 191 |
strm provides the memory allocation functions and window buffer on input, |
| 192 |
and provides information on the unused input on return. For Z_DATA_ERROR |
| 193 |
returns, strm will also provide an error message. |
| 194 |
|
| 195 |
in() and out() are the call-back input and output functions. When |
| 196 |
inflateBack() needs more input, it calls in(). When inflateBack() has |
| 197 |
filled the window with output, or when it completes with data in the |
| 198 |
window, it calls out() to write out the data. The application must not |
| 199 |
change the provided input until in() is called again or inflateBack() |
| 200 |
returns. The application must not change the window/output buffer until |
| 201 |
inflateBack() returns. |
| 202 |
|
| 203 |
in() and out() are called with a descriptor parameter provided in the |
| 204 |
inflateBack() call. This parameter can be a structure that provides the |
| 205 |
information required to do the read or write, as well as accumulated |
| 206 |
information on the input and output such as totals and check values. |
| 207 |
|
| 208 |
in() should return zero on failure. out() should return non-zero on |
| 209 |
failure. If either in() or out() fails, than inflateBack() returns a |
| 210 |
Z_BUF_ERROR. strm->next_in can be checked for Z_NULL to see whether it |
| 211 |
was in() or out() that caused in the error. Otherwise, inflateBack() |
| 212 |
returns Z_STREAM_END on success, Z_DATA_ERROR for an deflate format |
| 213 |
error, or Z_MEM_ERROR if it could not allocate memory for the state. |
| 214 |
inflateBack() can also return Z_STREAM_ERROR if the input parameters |
| 215 |
are not correct, i.e. strm is Z_NULL or the state was not initialized. |
| 216 |
*/ |
| 217 |
int ZEXPORT inflateBack9(strm, in, in_desc, out, out_desc) |
| 218 |
z_stream FAR *strm; |
| 219 |
in_func in; |
| 220 |
void FAR *in_desc; |
| 221 |
out_func out; |
| 222 |
void FAR *out_desc; |
| 223 |
{ |
| 224 |
struct inflate_state FAR *state; |
| 225 |
z_const unsigned char FAR *next; /* next input */ |
| 226 |
unsigned char FAR *put; /* next output */ |
| 227 |
unsigned have; /* available input */ |
| 228 |
unsigned long left; /* available output */ |
| 229 |
inflate_mode mode; /* current inflate mode */ |
| 230 |
int lastblock; /* true if processing last block */ |
| 231 |
int wrap; /* true if the window has wrapped */ |
| 232 |
unsigned char FAR *window; /* allocated sliding window, if needed */ |
| 233 |
unsigned long hold; /* bit buffer */ |
| 234 |
unsigned bits; /* bits in bit buffer */ |
| 235 |
unsigned extra; /* extra bits needed */ |
| 236 |
unsigned long length; /* literal or length of data to copy */ |
| 237 |
unsigned long offset; /* distance back to copy string from */ |
| 238 |
unsigned long copy; /* number of stored or match bytes to copy */ |
| 239 |
unsigned char FAR *from; /* where to copy match bytes from */ |
| 240 |
code const FAR *lencode; /* starting table for length/literal codes */ |
| 241 |
code const FAR *distcode; /* starting table for distance codes */ |
| 242 |
unsigned lenbits; /* index bits for lencode */ |
| 243 |
unsigned distbits; /* index bits for distcode */ |
| 244 |
code here; /* current decoding table entry */ |
| 245 |
code last; /* parent table entry */ |
| 246 |
unsigned len; /* length to copy for repeats, bits to drop */ |
| 247 |
int ret; /* return code */ |
| 248 |
static const unsigned short order[19] = /* permutation of code lengths */ |
| 249 |
{16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}; |
| 250 |
#include "inffix9.h" |
| 251 |
|
| 252 |
/* Check that the strm exists and that the state was initialized */ |
| 253 |
if (strm == Z_NULL || strm->state == Z_NULL) |
| 254 |
return Z_STREAM_ERROR; |
| 255 |
state = (struct inflate_state FAR *)strm->state; |
| 256 |
|
| 257 |
/* Reset the state */ |
| 258 |
strm->msg = Z_NULL; |
| 259 |
mode = TYPE; |
| 260 |
lastblock = 0; |
| 261 |
wrap = 0; |
| 262 |
window = state->window; |
| 263 |
next = strm->next_in; |
| 264 |
have = next != Z_NULL ? strm->avail_in : 0; |
| 265 |
hold = 0; |
| 266 |
bits = 0; |
| 267 |
put = window; |
| 268 |
left = WSIZE; |
| 269 |
lencode = Z_NULL; |
| 270 |
distcode = Z_NULL; |
| 271 |
|
| 272 |
/* Inflate until end of block marked as last */ |
| 273 |
for (;;) |
| 274 |
switch (mode) { |
| 275 |
case TYPE: |
| 276 |
/* determine and dispatch block type */ |
| 277 |
if (lastblock) { |
| 278 |
BYTEBITS(); |
| 279 |
mode = DONE; |
| 280 |
break; |
| 281 |
} |
| 282 |
NEEDBITS(3); |
| 283 |
lastblock = BITS(1); |
| 284 |
DROPBITS(1); |
| 285 |
switch (BITS(2)) { |
| 286 |
case 0: /* stored block */ |
| 287 |
Tracev((stderr, "inflate: stored block%s\n", |
| 288 |
lastblock ? " (last)" : "")); |
| 289 |
mode = STORED; |
| 290 |
break; |
| 291 |
case 1: /* fixed block */ |
| 292 |
lencode = lenfix; |
| 293 |
lenbits = 9; |
| 294 |
distcode = distfix; |
| 295 |
distbits = 5; |
| 296 |
Tracev((stderr, "inflate: fixed codes block%s\n", |
| 297 |
lastblock ? " (last)" : "")); |
| 298 |
mode = LEN; /* decode codes */ |
| 299 |
break; |
| 300 |
case 2: /* dynamic block */ |
| 301 |
Tracev((stderr, "inflate: dynamic codes block%s\n", |
| 302 |
lastblock ? " (last)" : "")); |
| 303 |
mode = TABLE; |
| 304 |
break; |
| 305 |
case 3: |
| 306 |
strm->msg = (char *)"invalid block type"; |
| 307 |
mode = BAD; |
| 308 |
} |
| 309 |
DROPBITS(2); |
| 310 |
break; |
| 311 |
|
| 312 |
case STORED: |
| 313 |
/* get and verify stored block length */ |
| 314 |
BYTEBITS(); /* go to byte boundary */ |
| 315 |
NEEDBITS(32); |
| 316 |
if ((hold & 0xffff) != ((hold >> 16) ^ 0xffff)) { |
| 317 |
strm->msg = (char *)"invalid stored block lengths"; |
| 318 |
mode = BAD; |
| 319 |
break; |
| 320 |
} |
| 321 |
length = (unsigned)hold & 0xffff; |
| 322 |
Tracev((stderr, "inflate: stored length %lu\n", |
| 323 |
length)); |
| 324 |
INITBITS(); |
| 325 |
|
| 326 |
/* copy stored block from input to output */ |
| 327 |
while (length != 0) { |
| 328 |
copy = length; |
| 329 |
PULL(); |
| 330 |
ROOM(); |
| 331 |
if (copy > have) copy = have; |
| 332 |
if (copy > left) copy = left; |
| 333 |
zmemcpy(put, next, copy); |
| 334 |
have -= copy; |
| 335 |
next += copy; |
| 336 |
left -= copy; |
| 337 |
put += copy; |
| 338 |
length -= copy; |
| 339 |
} |
| 340 |
Tracev((stderr, "inflate: stored end\n")); |
| 341 |
mode = TYPE; |
| 342 |
break; |
| 343 |
|
| 344 |
case TABLE: |
| 345 |
/* get dynamic table entries descriptor */ |
| 346 |
NEEDBITS(14); |
| 347 |
state->nlen = BITS(5) + 257; |
| 348 |
DROPBITS(5); |
| 349 |
state->ndist = BITS(5) + 1; |
| 350 |
DROPBITS(5); |
| 351 |
state->ncode = BITS(4) + 4; |
| 352 |
DROPBITS(4); |
| 353 |
if (state->nlen > 286) { |
| 354 |
strm->msg = (char *)"too many length symbols"; |
| 355 |
mode = BAD; |
| 356 |
break; |
| 357 |
} |
| 358 |
Tracev((stderr, "inflate: table sizes ok\n")); |
| 359 |
|
| 360 |
/* get code length code lengths (not a typo) */ |
| 361 |
state->have = 0; |
| 362 |
while (state->have < state->ncode) { |
| 363 |
NEEDBITS(3); |
| 364 |
state->lens[order[state->have++]] = (unsigned short)BITS(3); |
| 365 |
DROPBITS(3); |
| 366 |
} |
| 367 |
while (state->have < 19) |
| 368 |
state->lens[order[state->have++]] = 0; |
| 369 |
state->next = state->codes; |
| 370 |
lencode = (code const FAR *)(state->next); |
| 371 |
lenbits = 7; |
| 372 |
ret = inflate_table9(CODES, state->lens, 19, &(state->next), |
| 373 |
&(lenbits), state->work); |
| 374 |
if (ret) { |
| 375 |
strm->msg = (char *)"invalid code lengths set"; |
| 376 |
mode = BAD; |
| 377 |
break; |
| 378 |
} |
| 379 |
Tracev((stderr, "inflate: code lengths ok\n")); |
| 380 |
|
| 381 |
/* get length and distance code code lengths */ |
| 382 |
state->have = 0; |
| 383 |
while (state->have < state->nlen + state->ndist) { |
| 384 |
for (;;) { |
| 385 |
here = lencode[BITS(lenbits)]; |
| 386 |
if ((unsigned)(here.bits) <= bits) break; |
| 387 |
PULLBYTE(); |
| 388 |
} |
| 389 |
if (here.val < 16) { |
| 390 |
NEEDBITS(here.bits); |
| 391 |
DROPBITS(here.bits); |
| 392 |
state->lens[state->have++] = here.val; |
| 393 |
} |
| 394 |
else { |
| 395 |
if (here.val == 16) { |
| 396 |
NEEDBITS(here.bits + 2); |
| 397 |
DROPBITS(here.bits); |
| 398 |
if (state->have == 0) { |
| 399 |
strm->msg = (char *)"invalid bit length repeat"; |
| 400 |
mode = BAD; |
| 401 |
break; |
| 402 |
} |
| 403 |
len = (unsigned)(state->lens[state->have - 1]); |
| 404 |
copy = 3 + BITS(2); |
| 405 |
DROPBITS(2); |
| 406 |
} |
| 407 |
else if (here.val == 17) { |
| 408 |
NEEDBITS(here.bits + 3); |
| 409 |
DROPBITS(here.bits); |
| 410 |
len = 0; |
| 411 |
copy = 3 + BITS(3); |
| 412 |
DROPBITS(3); |
| 413 |
} |
| 414 |
else { |
| 415 |
NEEDBITS(here.bits + 7); |
| 416 |
DROPBITS(here.bits); |
| 417 |
len = 0; |
| 418 |
copy = 11 + BITS(7); |
| 419 |
DROPBITS(7); |
| 420 |
} |
| 421 |
if (state->have + copy > state->nlen + state->ndist) { |
| 422 |
strm->msg = (char *)"invalid bit length repeat"; |
| 423 |
mode = BAD; |
| 424 |
break; |
| 425 |
} |
| 426 |
while (copy--) |
| 427 |
state->lens[state->have++] = (unsigned short)len; |
| 428 |
} |
| 429 |
} |
| 430 |
|
| 431 |
/* handle error breaks in while */ |
| 432 |
if (mode == BAD) break; |
| 433 |
|
| 434 |
/* check for end-of-block code (better have one) */ |
| 435 |
if (state->lens[256] == 0) { |
| 436 |
strm->msg = (char *)"invalid code -- missing end-of-block"; |
| 437 |
mode = BAD; |
| 438 |
break; |
| 439 |
} |
| 440 |
|
| 441 |
/* build code tables -- note: do not change the lenbits or distbits |
| 442 |
values here (9 and 6) without reading the comments in inftree9.h |
| 443 |
concerning the ENOUGH constants, which depend on those values */ |
| 444 |
state->next = state->codes; |
| 445 |
lencode = (code const FAR *)(state->next); |
| 446 |
lenbits = 9; |
| 447 |
ret = inflate_table9(LENS, state->lens, state->nlen, |
| 448 |
&(state->next), &(lenbits), state->work); |
| 449 |
if (ret) { |
| 450 |
strm->msg = (char *)"invalid literal/lengths set"; |
| 451 |
mode = BAD; |
| 452 |
break; |
| 453 |
} |
| 454 |
distcode = (code const FAR *)(state->next); |
| 455 |
distbits = 6; |
| 456 |
ret = inflate_table9(DISTS, state->lens + state->nlen, |
| 457 |
state->ndist, &(state->next), &(distbits), |
| 458 |
state->work); |
| 459 |
if (ret) { |
| 460 |
strm->msg = (char *)"invalid distances set"; |
| 461 |
mode = BAD; |
| 462 |
break; |
| 463 |
} |
| 464 |
Tracev((stderr, "inflate: codes ok\n")); |
| 465 |
mode = LEN; |
| 466 |
|
| 467 |
case LEN: |
| 468 |
/* get a literal, length, or end-of-block code */ |
| 469 |
for (;;) { |
| 470 |
here = lencode[BITS(lenbits)]; |
| 471 |
if ((unsigned)(here.bits) <= bits) break; |
| 472 |
PULLBYTE(); |
| 473 |
} |
| 474 |
if (here.op && (here.op & 0xf0) == 0) { |
| 475 |
last = here; |
| 476 |
for (;;) { |
| 477 |
here = lencode[last.val + |
| 478 |
(BITS(last.bits + last.op) >> last.bits)]; |
| 479 |
if ((unsigned)(last.bits + here.bits) <= bits) break; |
| 480 |
PULLBYTE(); |
| 481 |
} |
| 482 |
DROPBITS(last.bits); |
| 483 |
} |
| 484 |
DROPBITS(here.bits); |
| 485 |
length = (unsigned)here.val; |
| 486 |
|
| 487 |
/* process literal */ |
| 488 |
if (here.op == 0) { |
| 489 |
Tracevv((stderr, here.val >= 0x20 && here.val < 0x7f ? |
| 490 |
"inflate: literal '%c'\n" : |
| 491 |
"inflate: literal 0x%02x\n", here.val)); |
| 492 |
ROOM(); |
| 493 |
*put++ = (unsigned char)(length); |
| 494 |
left--; |
| 495 |
mode = LEN; |
| 496 |
break; |
| 497 |
} |
| 498 |
|
| 499 |
/* process end of block */ |
| 500 |
if (here.op & 32) { |
| 501 |
Tracevv((stderr, "inflate: end of block\n")); |
| 502 |
mode = TYPE; |
| 503 |
break; |
| 504 |
} |
| 505 |
|
| 506 |
/* invalid code */ |
| 507 |
if (here.op & 64) { |
| 508 |
strm->msg = (char *)"invalid literal/length code"; |
| 509 |
mode = BAD; |
| 510 |
break; |
| 511 |
} |
| 512 |
|
| 513 |
/* length code -- get extra bits, if any */ |
| 514 |
extra = (unsigned)(here.op) & 31; |
| 515 |
if (extra != 0) { |
| 516 |
NEEDBITS(extra); |
| 517 |
length += BITS(extra); |
| 518 |
DROPBITS(extra); |
| 519 |
} |
| 520 |
Tracevv((stderr, "inflate: length %lu\n", length)); |
| 521 |
|
| 522 |
/* get distance code */ |
| 523 |
for (;;) { |
| 524 |
here = distcode[BITS(distbits)]; |
| 525 |
if ((unsigned)(here.bits) <= bits) break; |
| 526 |
PULLBYTE(); |
| 527 |
} |
| 528 |
if ((here.op & 0xf0) == 0) { |
| 529 |
last = here; |
| 530 |
for (;;) { |
| 531 |
here = distcode[last.val + |
| 532 |
(BITS(last.bits + last.op) >> last.bits)]; |
| 533 |
if ((unsigned)(last.bits + here.bits) <= bits) break; |
| 534 |
PULLBYTE(); |
| 535 |
} |
| 536 |
DROPBITS(last.bits); |
| 537 |
} |
| 538 |
DROPBITS(here.bits); |
| 539 |
if (here.op & 64) { |
| 540 |
strm->msg = (char *)"invalid distance code"; |
| 541 |
mode = BAD; |
| 542 |
break; |
| 543 |
} |
| 544 |
offset = (unsigned)here.val; |
| 545 |
|
| 546 |
/* get distance extra bits, if any */ |
| 547 |
extra = (unsigned)(here.op) & 15; |
| 548 |
if (extra != 0) { |
| 549 |
NEEDBITS(extra); |
| 550 |
offset += BITS(extra); |
| 551 |
DROPBITS(extra); |
| 552 |
} |
| 553 |
if (offset > WSIZE - (wrap ? 0: left)) { |
| 554 |
strm->msg = (char *)"invalid distance too far back"; |
| 555 |
mode = BAD; |
| 556 |
break; |
| 557 |
} |
| 558 |
Tracevv((stderr, "inflate: distance %lu\n", offset)); |
| 559 |
|
| 560 |
/* copy match from window to output */ |
| 561 |
do { |
| 562 |
ROOM(); |
| 563 |
copy = WSIZE - offset; |
| 564 |
if (copy < left) { |
| 565 |
from = put + copy; |
| 566 |
copy = left - copy; |
| 567 |
} |
| 568 |
else { |
| 569 |
from = put - offset; |
| 570 |
copy = left; |
| 571 |
} |
| 572 |
if (copy > length) copy = length; |
| 573 |
length -= copy; |
| 574 |
left -= copy; |
| 575 |
do { |
| 576 |
*put++ = *from++; |
| 577 |
} while (--copy); |
| 578 |
} while (length != 0); |
| 579 |
break; |
| 580 |
|
| 581 |
case DONE: |
| 582 |
/* inflate stream terminated properly -- write leftover output */ |
| 583 |
ret = Z_STREAM_END; |
| 584 |
if (left < WSIZE) { |
| 585 |
if (out(out_desc, window, (unsigned)(WSIZE - left))) |
| 586 |
ret = Z_BUF_ERROR; |
| 587 |
} |
| 588 |
goto inf_leave; |
| 589 |
|
| 590 |
case BAD: |
| 591 |
ret = Z_DATA_ERROR; |
| 592 |
goto inf_leave; |
| 593 |
|
| 594 |
default: /* can't happen, but makes compilers happy */ |
| 595 |
ret = Z_STREAM_ERROR; |
| 596 |
goto inf_leave; |
| 597 |
} |
| 598 |
|
| 599 |
/* Return unused input */ |
| 600 |
inf_leave: |
| 601 |
strm->next_in = next; |
| 602 |
strm->avail_in = have; |
| 603 |
return ret; |
| 604 |
} |
| 605 |
|
| 606 |
int ZEXPORT inflateBack9End(strm) |
| 607 |
z_stream FAR *strm; |
| 608 |
{ |
| 609 |
if (strm == Z_NULL || strm->state == Z_NULL || strm->zfree == (free_func)0) |
| 610 |
return Z_STREAM_ERROR; |
| 611 |
ZFREE(strm, strm->state); |
| 612 |
strm->state = Z_NULL; |
| 613 |
Tracev((stderr, "inflate: end\n")); |
| 614 |
return Z_OK; |
| 615 |
} |
