Annotation of embedaddon/rsync/zlib/inflate.c, revision 1.1
1.1 ! misho 1: /* inflate.c -- zlib decompression
! 2: * Copyright (C) 1995-2005 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 write == 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 void fixedtables OF((struct inflate_state FAR *state));
! 96: local int updatewindow OF((z_streamp strm, unsigned out));
! 97: #ifdef BUILDFIXED
! 98: void makefixed OF((void));
! 99: #endif
! 100: local unsigned syncsearch OF((unsigned FAR *have, unsigned char FAR *buf,
! 101: unsigned len));
! 102:
! 103: int ZEXPORT inflateReset(strm)
! 104: z_streamp strm;
! 105: {
! 106: struct inflate_state FAR *state;
! 107:
! 108: if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
! 109: state = (struct inflate_state FAR *)strm->state;
! 110: strm->total_in = strm->total_out = state->total = 0;
! 111: strm->msg = Z_NULL;
! 112: strm->adler = 1; /* to support ill-conceived Java test suite */
! 113: state->mode = HEAD;
! 114: state->last = 0;
! 115: state->havedict = 0;
! 116: state->dmax = 32768U;
! 117: state->head = Z_NULL;
! 118: state->wsize = 0;
! 119: state->whave = 0;
! 120: state->write = 0;
! 121: state->hold = 0;
! 122: state->bits = 0;
! 123: state->lencode = state->distcode = state->next = state->codes;
! 124: Tracev((stderr, "inflate: reset\n"));
! 125: return Z_OK;
! 126: }
! 127:
! 128: int ZEXPORT inflatePrime(strm, bits, value)
! 129: z_streamp strm;
! 130: int bits;
! 131: int value;
! 132: {
! 133: struct inflate_state FAR *state;
! 134:
! 135: if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
! 136: state = (struct inflate_state FAR *)strm->state;
! 137: if (bits > 16 || state->bits + bits > 32) return Z_STREAM_ERROR;
! 138: value &= (1L << bits) - 1;
! 139: state->hold += value << state->bits;
! 140: state->bits += bits;
! 141: return Z_OK;
! 142: }
! 143:
! 144: int ZEXPORT inflateInit2_(strm, windowBits, version, stream_size)
! 145: z_streamp strm;
! 146: int windowBits;
! 147: const char *version;
! 148: int stream_size;
! 149: {
! 150: struct inflate_state FAR *state;
! 151:
! 152: if (version == Z_NULL || version[0] != ZLIB_VERSION[0] ||
! 153: stream_size != (int)(sizeof(z_stream)))
! 154: return Z_VERSION_ERROR;
! 155: if (strm == Z_NULL) return Z_STREAM_ERROR;
! 156: strm->msg = Z_NULL; /* in case we return an error */
! 157: if (strm->zalloc == (alloc_func)0) {
! 158: strm->zalloc = zcalloc;
! 159: strm->opaque = (voidpf)0;
! 160: }
! 161: if (strm->zfree == (free_func)0) strm->zfree = zcfree;
! 162: state = (struct inflate_state FAR *)
! 163: ZALLOC(strm, 1, sizeof(struct inflate_state));
! 164: if (state == Z_NULL) return Z_MEM_ERROR;
! 165: Tracev((stderr, "inflate: allocated\n"));
! 166: strm->state = (struct internal_state FAR *)state;
! 167: if (windowBits < 0) {
! 168: state->wrap = 0;
! 169: windowBits = -windowBits;
! 170: }
! 171: else {
! 172: state->wrap = (windowBits >> 4) + 1;
! 173: #ifdef GUNZIP
! 174: if (windowBits < 48) windowBits &= 15;
! 175: #endif
! 176: }
! 177: if (windowBits < 8 || windowBits > 15) {
! 178: ZFREE(strm, state);
! 179: strm->state = Z_NULL;
! 180: return Z_STREAM_ERROR;
! 181: }
! 182: state->wbits = (unsigned)windowBits;
! 183: state->window = Z_NULL;
! 184: return inflateReset(strm);
! 185: }
! 186:
! 187: int ZEXPORT inflateInit_(strm, version, stream_size)
! 188: z_streamp strm;
! 189: const char *version;
! 190: int stream_size;
! 191: {
! 192: return inflateInit2_(strm, DEF_WBITS, version, stream_size);
! 193: }
! 194:
! 195: /*
! 196: Return state with length and distance decoding tables and index sizes set to
! 197: fixed code decoding. Normally this returns fixed tables from inffixed.h.
! 198: If BUILDFIXED is defined, then instead this routine builds the tables the
! 199: first time it's called, and returns those tables the first time and
! 200: thereafter. This reduces the size of the code by about 2K bytes, in
! 201: exchange for a little execution time. However, BUILDFIXED should not be
! 202: used for threaded applications, since the rewriting of the tables and virgin
! 203: may not be thread-safe.
! 204: */
! 205: local void fixedtables(state)
! 206: struct inflate_state FAR *state;
! 207: {
! 208: #ifdef BUILDFIXED
! 209: static int virgin = 1;
! 210: static code *lenfix, *distfix;
! 211: static code fixed[544];
! 212:
! 213: /* build fixed huffman tables if first call (may not be thread safe) */
! 214: if (virgin) {
! 215: unsigned sym, bits;
! 216: static code *next;
! 217:
! 218: /* literal/length table */
! 219: sym = 0;
! 220: while (sym < 144) state->lens[sym++] = 8;
! 221: while (sym < 256) state->lens[sym++] = 9;
! 222: while (sym < 280) state->lens[sym++] = 7;
! 223: while (sym < 288) state->lens[sym++] = 8;
! 224: next = fixed;
! 225: lenfix = next;
! 226: bits = 9;
! 227: inflate_table(LENS, state->lens, 288, &(next), &(bits), state->work);
! 228:
! 229: /* distance table */
! 230: sym = 0;
! 231: while (sym < 32) state->lens[sym++] = 5;
! 232: distfix = next;
! 233: bits = 5;
! 234: inflate_table(DISTS, state->lens, 32, &(next), &(bits), state->work);
! 235:
! 236: /* do this just once */
! 237: virgin = 0;
! 238: }
! 239: #else /* !BUILDFIXED */
! 240: # include "inffixed.h"
! 241: #endif /* BUILDFIXED */
! 242: state->lencode = lenfix;
! 243: state->lenbits = 9;
! 244: state->distcode = distfix;
! 245: state->distbits = 5;
! 246: }
! 247:
! 248: #ifdef MAKEFIXED
! 249: #include <stdio.h>
! 250:
! 251: /*
! 252: Write out the inffixed.h that is #include'd above. Defining MAKEFIXED also
! 253: defines BUILDFIXED, so the tables are built on the fly. makefixed() writes
! 254: those tables to stdout, which would be piped to inffixed.h. A small program
! 255: can simply call makefixed to do this:
! 256:
! 257: void makefixed(void);
! 258:
! 259: int main(void)
! 260: {
! 261: makefixed();
! 262: return 0;
! 263: }
! 264:
! 265: Then that can be linked with zlib built with MAKEFIXED defined and run:
! 266:
! 267: a.out > inffixed.h
! 268: */
! 269: void makefixed()
! 270: {
! 271: unsigned low, size;
! 272: struct inflate_state state;
! 273:
! 274: fixedtables(&state);
! 275: puts(" /* inffixed.h -- table for decoding fixed codes");
! 276: puts(" * Generated automatically by makefixed().");
! 277: puts(" */");
! 278: puts("");
! 279: puts(" /* WARNING: this file should *not* be used by applications.");
! 280: puts(" It is part of the implementation of this library and is");
! 281: puts(" subject to change. Applications should only use zlib.h.");
! 282: puts(" */");
! 283: puts("");
! 284: size = 1U << 9;
! 285: printf(" static const code lenfix[%u] = {", size);
! 286: low = 0;
! 287: for (;;) {
! 288: if ((low % 7) == 0) printf("\n ");
! 289: printf("{%u,%u,%d}", state.lencode[low].op, state.lencode[low].bits,
! 290: state.lencode[low].val);
! 291: if (++low == size) break;
! 292: putchar(',');
! 293: }
! 294: puts("\n };");
! 295: size = 1U << 5;
! 296: printf("\n static const code distfix[%u] = {", size);
! 297: low = 0;
! 298: for (;;) {
! 299: if ((low % 6) == 0) printf("\n ");
! 300: printf("{%u,%u,%d}", state.distcode[low].op, state.distcode[low].bits,
! 301: state.distcode[low].val);
! 302: if (++low == size) break;
! 303: putchar(',');
! 304: }
! 305: puts("\n };");
! 306: }
! 307: #endif /* MAKEFIXED */
! 308:
! 309: /*
! 310: Update the window with the last wsize (normally 32K) bytes written before
! 311: returning. If window does not exist yet, create it. This is only called
! 312: when a window is already in use, or when output has been written during this
! 313: inflate call, but the end of the deflate stream has not been reached yet.
! 314: It is also called to create a window for dictionary data when a dictionary
! 315: is loaded.
! 316:
! 317: Providing output buffers larger than 32K to inflate() should provide a speed
! 318: advantage, since only the last 32K of output is copied to the sliding window
! 319: upon return from inflate(), and since all distances after the first 32K of
! 320: output will fall in the output data, making match copies simpler and faster.
! 321: The advantage may be dependent on the size of the processor's data caches.
! 322: */
! 323: local int updatewindow(strm, out)
! 324: z_streamp strm;
! 325: unsigned out;
! 326: {
! 327: struct inflate_state FAR *state;
! 328: unsigned copy, dist;
! 329:
! 330: state = (struct inflate_state FAR *)strm->state;
! 331:
! 332: /* if it hasn't been done already, allocate space for the window */
! 333: if (state->window == Z_NULL) {
! 334: state->window = (unsigned char FAR *)
! 335: ZALLOC(strm, 1U << state->wbits,
! 336: sizeof(unsigned char));
! 337: if (state->window == Z_NULL) return 1;
! 338: }
! 339:
! 340: /* if window not in use yet, initialize */
! 341: if (state->wsize == 0) {
! 342: state->wsize = 1U << state->wbits;
! 343: state->write = 0;
! 344: state->whave = 0;
! 345: }
! 346:
! 347: /* copy state->wsize or less output bytes into the circular window */
! 348: copy = out - strm->avail_out;
! 349: if (copy >= state->wsize) {
! 350: zmemcpy(state->window, strm->next_out - state->wsize, state->wsize);
! 351: state->write = 0;
! 352: state->whave = state->wsize;
! 353: }
! 354: else {
! 355: dist = state->wsize - state->write;
! 356: if (dist > copy) dist = copy;
! 357: zmemcpy(state->window + state->write, strm->next_out - copy, dist);
! 358: copy -= dist;
! 359: if (copy) {
! 360: zmemcpy(state->window, strm->next_out - copy, copy);
! 361: state->write = copy;
! 362: state->whave = state->wsize;
! 363: }
! 364: else {
! 365: state->write += dist;
! 366: if (state->write == state->wsize) state->write = 0;
! 367: if (state->whave < state->wsize) state->whave += dist;
! 368: }
! 369: }
! 370: return 0;
! 371: }
! 372:
! 373: /* Macros for inflate(): */
! 374:
! 375: /* check function to use adler32() for zlib or crc32() for gzip */
! 376: #ifdef GUNZIP
! 377: # define UPDATE(check, buf, len) \
! 378: (state->flags ? crc32(check, buf, len) : adler32(check, buf, len))
! 379: #else
! 380: # define UPDATE(check, buf, len) adler32(check, buf, len)
! 381: #endif
! 382:
! 383: /* check macros for header crc */
! 384: #ifdef GUNZIP
! 385: # define CRC2(check, word) \
! 386: do { \
! 387: hbuf[0] = (unsigned char)(word); \
! 388: hbuf[1] = (unsigned char)((word) >> 8); \
! 389: check = crc32(check, hbuf, 2); \
! 390: } while (0)
! 391:
! 392: # define CRC4(check, word) \
! 393: do { \
! 394: hbuf[0] = (unsigned char)(word); \
! 395: hbuf[1] = (unsigned char)((word) >> 8); \
! 396: hbuf[2] = (unsigned char)((word) >> 16); \
! 397: hbuf[3] = (unsigned char)((word) >> 24); \
! 398: check = crc32(check, hbuf, 4); \
! 399: } while (0)
! 400: #endif
! 401:
! 402: /* Load registers with state in inflate() for speed */
! 403: #define LOAD() \
! 404: do { \
! 405: put = strm->next_out; \
! 406: left = strm->avail_out; \
! 407: next = strm->next_in; \
! 408: have = strm->avail_in; \
! 409: hold = state->hold; \
! 410: bits = state->bits; \
! 411: } while (0)
! 412:
! 413: /* Restore state from registers in inflate() */
! 414: #define RESTORE() \
! 415: do { \
! 416: strm->next_out = put; \
! 417: strm->avail_out = left; \
! 418: strm->next_in = next; \
! 419: strm->avail_in = have; \
! 420: state->hold = hold; \
! 421: state->bits = bits; \
! 422: } while (0)
! 423:
! 424: /* Clear the input bit accumulator */
! 425: #define INITBITS() \
! 426: do { \
! 427: hold = 0; \
! 428: bits = 0; \
! 429: } while (0)
! 430:
! 431: /* Get a byte of input into the bit accumulator, or return from inflate()
! 432: if there is no input available. */
! 433: #define PULLBYTE() \
! 434: do { \
! 435: if (have == 0) goto inf_leave; \
! 436: have--; \
! 437: hold += (unsigned long)(*next++) << bits; \
! 438: bits += 8; \
! 439: } while (0)
! 440:
! 441: /* Assure that there are at least n bits in the bit accumulator. If there is
! 442: not enough available input to do that, then return from inflate(). */
! 443: #define NEEDBITS(n) \
! 444: do { \
! 445: while (bits < (unsigned)(n)) \
! 446: PULLBYTE(); \
! 447: } while (0)
! 448:
! 449: /* Return the low n bits of the bit accumulator (n < 16) */
! 450: #define BITS(n) \
! 451: ((unsigned)hold & ((1U << (n)) - 1))
! 452:
! 453: /* Remove n bits from the bit accumulator */
! 454: #define DROPBITS(n) \
! 455: do { \
! 456: hold >>= (n); \
! 457: bits -= (unsigned)(n); \
! 458: } while (0)
! 459:
! 460: /* Remove zero to seven bits as needed to go to a byte boundary */
! 461: #define BYTEBITS() \
! 462: do { \
! 463: hold >>= bits & 7; \
! 464: bits -= bits & 7; \
! 465: } while (0)
! 466:
! 467: /* Reverse the bytes in a 32-bit value */
! 468: #define REVERSE(q) \
! 469: ((((q) >> 24) & 0xff) + (((q) >> 8) & 0xff00) + \
! 470: (((q) & 0xff00) << 8) + (((q) & 0xff) << 24))
! 471:
! 472: /*
! 473: inflate() uses a state machine to process as much input data and generate as
! 474: much output data as possible before returning. The state machine is
! 475: structured roughly as follows:
! 476:
! 477: for (;;) switch (state) {
! 478: ...
! 479: case STATEn:
! 480: if (not enough input data or output space to make progress)
! 481: return;
! 482: ... make progress ...
! 483: state = STATEm;
! 484: break;
! 485: ...
! 486: }
! 487:
! 488: so when inflate() is called again, the same case is attempted again, and
! 489: if the appropriate resources are provided, the machine proceeds to the
! 490: next state. The NEEDBITS() macro is usually the way the state evaluates
! 491: whether it can proceed or should return. NEEDBITS() does the return if
! 492: the requested bits are not available. The typical use of the BITS macros
! 493: is:
! 494:
! 495: NEEDBITS(n);
! 496: ... do something with BITS(n) ...
! 497: DROPBITS(n);
! 498:
! 499: where NEEDBITS(n) either returns from inflate() if there isn't enough
! 500: input left to load n bits into the accumulator, or it continues. BITS(n)
! 501: gives the low n bits in the accumulator. When done, DROPBITS(n) drops
! 502: the low n bits off the accumulator. INITBITS() clears the accumulator
! 503: and sets the number of available bits to zero. BYTEBITS() discards just
! 504: enough bits to put the accumulator on a byte boundary. After BYTEBITS()
! 505: and a NEEDBITS(8), then BITS(8) would return the next byte in the stream.
! 506:
! 507: NEEDBITS(n) uses PULLBYTE() to get an available byte of input, or to return
! 508: if there is no input available. The decoding of variable length codes uses
! 509: PULLBYTE() directly in order to pull just enough bytes to decode the next
! 510: code, and no more.
! 511:
! 512: Some states loop until they get enough input, making sure that enough
! 513: state information is maintained to continue the loop where it left off
! 514: if NEEDBITS() returns in the loop. For example, want, need, and keep
! 515: would all have to actually be part of the saved state in case NEEDBITS()
! 516: returns:
! 517:
! 518: case STATEw:
! 519: while (want < need) {
! 520: NEEDBITS(n);
! 521: keep[want++] = BITS(n);
! 522: DROPBITS(n);
! 523: }
! 524: state = STATEx;
! 525: case STATEx:
! 526:
! 527: As shown above, if the next state is also the next case, then the break
! 528: is omitted.
! 529:
! 530: A state may also return if there is not enough output space available to
! 531: complete that state. Those states are copying stored data, writing a
! 532: literal byte, and copying a matching string.
! 533:
! 534: When returning, a "goto inf_leave" is used to update the total counters,
! 535: update the check value, and determine whether any progress has been made
! 536: during that inflate() call in order to return the proper return code.
! 537: Progress is defined as a change in either strm->avail_in or strm->avail_out.
! 538: When there is a window, goto inf_leave will update the window with the last
! 539: output written. If a goto inf_leave occurs in the middle of decompression
! 540: and there is no window currently, goto inf_leave will create one and copy
! 541: output to the window for the next call of inflate().
! 542:
! 543: In this implementation, the flush parameter of inflate() only affects the
! 544: return code (per zlib.h). inflate() always writes as much as possible to
! 545: strm->next_out, given the space available and the provided input--the effect
! 546: documented in zlib.h of Z_SYNC_FLUSH. Furthermore, inflate() always defers
! 547: the allocation of and copying into a sliding window until necessary, which
! 548: provides the effect documented in zlib.h for Z_FINISH when the entire input
! 549: stream available. So the only thing the flush parameter actually does is:
! 550: when flush is set to Z_FINISH, inflate() cannot return Z_OK. Instead it
! 551: will return Z_BUF_ERROR if it has not reached the end of the stream.
! 552: */
! 553:
! 554: int ZEXPORT inflate(strm, flush)
! 555: z_streamp strm;
! 556: int flush;
! 557: {
! 558: struct inflate_state FAR *state;
! 559: unsigned char FAR *next; /* next input */
! 560: unsigned char FAR *put; /* next output */
! 561: unsigned have, left; /* available input and output */
! 562: unsigned long hold; /* bit buffer */
! 563: unsigned bits; /* bits in bit buffer */
! 564: unsigned in, out; /* save starting available input and output */
! 565: unsigned copy; /* number of stored or match bytes to copy */
! 566: unsigned char FAR *from; /* where to copy match bytes from */
! 567: code this; /* current decoding table entry */
! 568: code last; /* parent table entry */
! 569: unsigned len; /* length to copy for repeats, bits to drop */
! 570: int ret; /* return code */
! 571: #ifdef GUNZIP
! 572: unsigned char hbuf[4]; /* buffer for gzip header crc calculation */
! 573: #endif
! 574: static const unsigned short order[19] = /* permutation of code lengths */
! 575: {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
! 576:
! 577: if (strm == Z_NULL || strm->state == Z_NULL || strm->next_out == Z_NULL ||
! 578: (strm->next_in == Z_NULL && strm->avail_in != 0))
! 579: return Z_STREAM_ERROR;
! 580:
! 581: state = (struct inflate_state FAR *)strm->state;
! 582: if (state->mode == TYPE) state->mode = TYPEDO; /* skip check */
! 583: LOAD();
! 584: in = have;
! 585: out = left;
! 586: ret = Z_OK;
! 587: for (;;)
! 588: switch (state->mode) {
! 589: case HEAD:
! 590: if (state->wrap == 0) {
! 591: state->mode = TYPEDO;
! 592: break;
! 593: }
! 594: NEEDBITS(16);
! 595: #ifdef GUNZIP
! 596: if ((state->wrap & 2) && hold == 0x8b1f) { /* gzip header */
! 597: state->check = crc32(0L, Z_NULL, 0);
! 598: CRC2(state->check, hold);
! 599: INITBITS();
! 600: state->mode = FLAGS;
! 601: break;
! 602: }
! 603: state->flags = 0; /* expect zlib header */
! 604: if (state->head != Z_NULL)
! 605: state->head->done = -1;
! 606: if (!(state->wrap & 1) || /* check if zlib header allowed */
! 607: #else
! 608: if (
! 609: #endif
! 610: ((BITS(8) << 8) + (hold >> 8)) % 31) {
! 611: strm->msg = (char *)"incorrect header check";
! 612: state->mode = BAD;
! 613: break;
! 614: }
! 615: if (BITS(4) != Z_DEFLATED) {
! 616: strm->msg = (char *)"unknown compression method";
! 617: state->mode = BAD;
! 618: break;
! 619: }
! 620: DROPBITS(4);
! 621: len = BITS(4) + 8;
! 622: if (len > state->wbits) {
! 623: strm->msg = (char *)"invalid window size";
! 624: state->mode = BAD;
! 625: break;
! 626: }
! 627: state->dmax = 1U << len;
! 628: Tracev((stderr, "inflate: zlib header ok\n"));
! 629: strm->adler = state->check = adler32(0L, Z_NULL, 0);
! 630: state->mode = hold & 0x200 ? DICTID : TYPE;
! 631: INITBITS();
! 632: break;
! 633: #ifdef GUNZIP
! 634: case FLAGS:
! 635: NEEDBITS(16);
! 636: state->flags = (int)(hold);
! 637: if ((state->flags & 0xff) != Z_DEFLATED) {
! 638: strm->msg = (char *)"unknown compression method";
! 639: state->mode = BAD;
! 640: break;
! 641: }
! 642: if (state->flags & 0xe000) {
! 643: strm->msg = (char *)"unknown header flags set";
! 644: state->mode = BAD;
! 645: break;
! 646: }
! 647: if (state->head != Z_NULL)
! 648: state->head->text = (int)((hold >> 8) & 1);
! 649: if (state->flags & 0x0200) CRC2(state->check, hold);
! 650: INITBITS();
! 651: state->mode = TIME;
! 652: /* FALL THROUGH */
! 653: case TIME:
! 654: NEEDBITS(32);
! 655: if (state->head != Z_NULL)
! 656: state->head->time = hold;
! 657: if (state->flags & 0x0200) CRC4(state->check, hold);
! 658: INITBITS();
! 659: state->mode = OS;
! 660: /* FALL THROUGH */
! 661: case OS:
! 662: NEEDBITS(16);
! 663: if (state->head != Z_NULL) {
! 664: state->head->xflags = (int)(hold & 0xff);
! 665: state->head->os = (int)(hold >> 8);
! 666: }
! 667: if (state->flags & 0x0200) CRC2(state->check, hold);
! 668: INITBITS();
! 669: state->mode = EXLEN;
! 670: /* FALL THROUGH */
! 671: case EXLEN:
! 672: if (state->flags & 0x0400) {
! 673: NEEDBITS(16);
! 674: state->length = (unsigned)(hold);
! 675: if (state->head != Z_NULL)
! 676: state->head->extra_len = (unsigned)hold;
! 677: if (state->flags & 0x0200) CRC2(state->check, hold);
! 678: INITBITS();
! 679: }
! 680: else if (state->head != Z_NULL)
! 681: state->head->extra = Z_NULL;
! 682: state->mode = EXTRA;
! 683: /* FALL THROUGH */
! 684: case EXTRA:
! 685: if (state->flags & 0x0400) {
! 686: copy = state->length;
! 687: if (copy > have) copy = have;
! 688: if (copy) {
! 689: if (state->head != Z_NULL &&
! 690: state->head->extra != Z_NULL) {
! 691: len = state->head->extra_len - state->length;
! 692: zmemcpy(state->head->extra + len, next,
! 693: len + copy > state->head->extra_max ?
! 694: state->head->extra_max - len : copy);
! 695: }
! 696: if (state->flags & 0x0200)
! 697: state->check = crc32(state->check, next, copy);
! 698: have -= copy;
! 699: next += copy;
! 700: state->length -= copy;
! 701: }
! 702: if (state->length) goto inf_leave;
! 703: }
! 704: state->length = 0;
! 705: state->mode = NAME;
! 706: /* FALL THROUGH */
! 707: case NAME:
! 708: if (state->flags & 0x0800) {
! 709: if (have == 0) goto inf_leave;
! 710: copy = 0;
! 711: do {
! 712: len = (unsigned)(next[copy++]);
! 713: if (state->head != Z_NULL &&
! 714: state->head->name != Z_NULL &&
! 715: state->length < state->head->name_max)
! 716: state->head->name[state->length++] = len;
! 717: } while (len && copy < have);
! 718: if (state->flags & 0x0200)
! 719: state->check = crc32(state->check, next, copy);
! 720: have -= copy;
! 721: next += copy;
! 722: if (len) goto inf_leave;
! 723: }
! 724: else if (state->head != Z_NULL)
! 725: state->head->name = Z_NULL;
! 726: state->length = 0;
! 727: state->mode = COMMENT;
! 728: /* FALL THROUGH */
! 729: case COMMENT:
! 730: if (state->flags & 0x1000) {
! 731: if (have == 0) goto inf_leave;
! 732: copy = 0;
! 733: do {
! 734: len = (unsigned)(next[copy++]);
! 735: if (state->head != Z_NULL &&
! 736: state->head->comment != Z_NULL &&
! 737: state->length < state->head->comm_max)
! 738: state->head->comment[state->length++] = len;
! 739: } while (len && copy < have);
! 740: if (state->flags & 0x0200)
! 741: state->check = crc32(state->check, next, copy);
! 742: have -= copy;
! 743: next += copy;
! 744: if (len) goto inf_leave;
! 745: }
! 746: else if (state->head != Z_NULL)
! 747: state->head->comment = Z_NULL;
! 748: state->mode = HCRC;
! 749: /* FALL THROUGH */
! 750: case HCRC:
! 751: if (state->flags & 0x0200) {
! 752: NEEDBITS(16);
! 753: if (hold != (state->check & 0xffff)) {
! 754: strm->msg = (char *)"header crc mismatch";
! 755: state->mode = BAD;
! 756: break;
! 757: }
! 758: INITBITS();
! 759: }
! 760: if (state->head != Z_NULL) {
! 761: state->head->hcrc = (int)((state->flags >> 9) & 1);
! 762: state->head->done = 1;
! 763: }
! 764: strm->adler = state->check = crc32(0L, Z_NULL, 0);
! 765: state->mode = TYPE;
! 766: break;
! 767: #endif
! 768: case DICTID:
! 769: NEEDBITS(32);
! 770: strm->adler = state->check = REVERSE(hold);
! 771: INITBITS();
! 772: state->mode = DICT;
! 773: /* FALL THROUGH */
! 774: case DICT:
! 775: if (state->havedict == 0) {
! 776: RESTORE();
! 777: return Z_NEED_DICT;
! 778: }
! 779: strm->adler = state->check = adler32(0L, Z_NULL, 0);
! 780: state->mode = TYPE;
! 781: /* FALL THROUGH */
! 782: case TYPE:
! 783: if (flush == Z_BLOCK) goto inf_leave;
! 784: /* FALL THROUGH */
! 785: case TYPEDO:
! 786: if (state->last) {
! 787: BYTEBITS();
! 788: state->mode = CHECK;
! 789: break;
! 790: }
! 791: NEEDBITS(3);
! 792: state->last = BITS(1);
! 793: DROPBITS(1);
! 794: switch (BITS(2)) {
! 795: case 0: /* stored block */
! 796: Tracev((stderr, "inflate: stored block%s\n",
! 797: state->last ? " (last)" : ""));
! 798: state->mode = STORED;
! 799: break;
! 800: case 1: /* fixed block */
! 801: fixedtables(state);
! 802: Tracev((stderr, "inflate: fixed codes block%s\n",
! 803: state->last ? " (last)" : ""));
! 804: state->mode = LEN; /* decode codes */
! 805: break;
! 806: case 2: /* dynamic block */
! 807: Tracev((stderr, "inflate: dynamic codes block%s\n",
! 808: state->last ? " (last)" : ""));
! 809: state->mode = TABLE;
! 810: break;
! 811: case 3:
! 812: strm->msg = (char *)"invalid block type";
! 813: state->mode = BAD;
! 814: }
! 815: DROPBITS(2);
! 816: break;
! 817: case STORED:
! 818: BYTEBITS(); /* go to byte boundary */
! 819: NEEDBITS(32);
! 820: if ((hold & 0xffff) != ((hold >> 16) ^ 0xffff)) {
! 821: strm->msg = (char *)"invalid stored block lengths";
! 822: state->mode = BAD;
! 823: break;
! 824: }
! 825: state->length = (unsigned)hold & 0xffff;
! 826: Tracev((stderr, "inflate: stored length %u\n",
! 827: state->length));
! 828: INITBITS();
! 829: state->mode = COPY;
! 830: /* FALL THROUGH */
! 831: case COPY:
! 832: copy = state->length;
! 833: if (copy) {
! 834: if (copy > have) copy = have;
! 835: if (copy > left) copy = left;
! 836: if (copy == 0) goto inf_leave;
! 837: zmemcpy(put, next, copy);
! 838: have -= copy;
! 839: next += copy;
! 840: left -= copy;
! 841: put += copy;
! 842: state->length -= copy;
! 843: break;
! 844: }
! 845: Tracev((stderr, "inflate: stored end\n"));
! 846: state->mode = TYPE;
! 847: break;
! 848: case TABLE:
! 849: NEEDBITS(14);
! 850: state->nlen = BITS(5) + 257;
! 851: DROPBITS(5);
! 852: state->ndist = BITS(5) + 1;
! 853: DROPBITS(5);
! 854: state->ncode = BITS(4) + 4;
! 855: DROPBITS(4);
! 856: #ifndef PKZIP_BUG_WORKAROUND
! 857: if (state->nlen > 286 || state->ndist > 30) {
! 858: strm->msg = (char *)"too many length or distance symbols";
! 859: state->mode = BAD;
! 860: break;
! 861: }
! 862: #endif
! 863: Tracev((stderr, "inflate: table sizes ok\n"));
! 864: state->have = 0;
! 865: state->mode = LENLENS;
! 866: /* FALL THROUGH */
! 867: case LENLENS:
! 868: while (state->have < state->ncode) {
! 869: NEEDBITS(3);
! 870: state->lens[order[state->have++]] = (unsigned short)BITS(3);
! 871: DROPBITS(3);
! 872: }
! 873: while (state->have < 19)
! 874: state->lens[order[state->have++]] = 0;
! 875: state->next = state->codes;
! 876: state->lencode = (code const FAR *)(state->next);
! 877: state->lenbits = 7;
! 878: ret = inflate_table(CODES, state->lens, 19, &(state->next),
! 879: &(state->lenbits), state->work);
! 880: if (ret) {
! 881: strm->msg = (char *)"invalid code lengths set";
! 882: state->mode = BAD;
! 883: break;
! 884: }
! 885: Tracev((stderr, "inflate: code lengths ok\n"));
! 886: state->have = 0;
! 887: state->mode = CODELENS;
! 888: /* FALL THROUGH */
! 889: case CODELENS:
! 890: while (state->have < state->nlen + state->ndist) {
! 891: for (;;) {
! 892: this = state->lencode[BITS(state->lenbits)];
! 893: if ((unsigned)(this.bits) <= bits) break;
! 894: PULLBYTE();
! 895: }
! 896: if (this.val < 16) {
! 897: NEEDBITS(this.bits);
! 898: DROPBITS(this.bits);
! 899: state->lens[state->have++] = this.val;
! 900: }
! 901: else {
! 902: if (this.val == 16) {
! 903: NEEDBITS(this.bits + 2);
! 904: DROPBITS(this.bits);
! 905: if (state->have == 0) {
! 906: strm->msg = (char *)"invalid bit length repeat";
! 907: state->mode = BAD;
! 908: break;
! 909: }
! 910: len = state->lens[state->have - 1];
! 911: copy = 3 + BITS(2);
! 912: DROPBITS(2);
! 913: }
! 914: else if (this.val == 17) {
! 915: NEEDBITS(this.bits + 3);
! 916: DROPBITS(this.bits);
! 917: len = 0;
! 918: copy = 3 + BITS(3);
! 919: DROPBITS(3);
! 920: }
! 921: else {
! 922: NEEDBITS(this.bits + 7);
! 923: DROPBITS(this.bits);
! 924: len = 0;
! 925: copy = 11 + BITS(7);
! 926: DROPBITS(7);
! 927: }
! 928: if (state->have + copy > state->nlen + state->ndist) {
! 929: strm->msg = (char *)"invalid bit length repeat";
! 930: state->mode = BAD;
! 931: break;
! 932: }
! 933: while (copy--)
! 934: state->lens[state->have++] = (unsigned short)len;
! 935: }
! 936: }
! 937:
! 938: /* handle error breaks in while */
! 939: if (state->mode == BAD) break;
! 940:
! 941: /* build code tables */
! 942: state->next = state->codes;
! 943: state->lencode = (code const FAR *)(state->next);
! 944: state->lenbits = 9;
! 945: ret = inflate_table(LENS, state->lens, state->nlen, &(state->next),
! 946: &(state->lenbits), state->work);
! 947: if (ret) {
! 948: strm->msg = (char *)"invalid literal/lengths set";
! 949: state->mode = BAD;
! 950: break;
! 951: }
! 952: state->distcode = (code const FAR *)(state->next);
! 953: state->distbits = 6;
! 954: ret = inflate_table(DISTS, state->lens + state->nlen, state->ndist,
! 955: &(state->next), &(state->distbits), state->work);
! 956: if (ret) {
! 957: strm->msg = (char *)"invalid distances set";
! 958: state->mode = BAD;
! 959: break;
! 960: }
! 961: Tracev((stderr, "inflate: codes ok\n"));
! 962: state->mode = LEN;
! 963: /* FALL THROUGH */
! 964: case LEN:
! 965: if (have >= 6 && left >= 258) {
! 966: RESTORE();
! 967: inflate_fast(strm, out);
! 968: LOAD();
! 969: break;
! 970: }
! 971: for (;;) {
! 972: this = state->lencode[BITS(state->lenbits)];
! 973: if ((unsigned)(this.bits) <= bits) break;
! 974: PULLBYTE();
! 975: }
! 976: if (this.op && (this.op & 0xf0) == 0) {
! 977: last = this;
! 978: for (;;) {
! 979: this = state->lencode[last.val +
! 980: (BITS(last.bits + last.op) >> last.bits)];
! 981: if ((unsigned)(last.bits + this.bits) <= bits) break;
! 982: PULLBYTE();
! 983: }
! 984: DROPBITS(last.bits);
! 985: }
! 986: DROPBITS(this.bits);
! 987: state->length = (unsigned)this.val;
! 988: if ((int)(this.op) == 0) {
! 989: Tracevv((stderr, this.val >= 0x20 && this.val < 0x7f ?
! 990: "inflate: literal '%c'\n" :
! 991: "inflate: literal 0x%02x\n", this.val));
! 992: state->mode = LIT;
! 993: break;
! 994: }
! 995: if (this.op & 32) {
! 996: Tracevv((stderr, "inflate: end of block\n"));
! 997: state->mode = TYPE;
! 998: break;
! 999: }
! 1000: if (this.op & 64) {
! 1001: strm->msg = (char *)"invalid literal/length code";
! 1002: state->mode = BAD;
! 1003: break;
! 1004: }
! 1005: state->extra = (unsigned)(this.op) & 15;
! 1006: state->mode = LENEXT;
! 1007: /* FALL THROUGH */
! 1008: case LENEXT:
! 1009: if (state->extra) {
! 1010: NEEDBITS(state->extra);
! 1011: state->length += BITS(state->extra);
! 1012: DROPBITS(state->extra);
! 1013: }
! 1014: Tracevv((stderr, "inflate: length %u\n", state->length));
! 1015: state->mode = DIST;
! 1016: /* FALL THROUGH */
! 1017: case DIST:
! 1018: for (;;) {
! 1019: this = state->distcode[BITS(state->distbits)];
! 1020: if ((unsigned)(this.bits) <= bits) break;
! 1021: PULLBYTE();
! 1022: }
! 1023: if ((this.op & 0xf0) == 0) {
! 1024: last = this;
! 1025: for (;;) {
! 1026: this = state->distcode[last.val +
! 1027: (BITS(last.bits + last.op) >> last.bits)];
! 1028: if ((unsigned)(last.bits + this.bits) <= bits) break;
! 1029: PULLBYTE();
! 1030: }
! 1031: DROPBITS(last.bits);
! 1032: }
! 1033: DROPBITS(this.bits);
! 1034: if (this.op & 64) {
! 1035: strm->msg = (char *)"invalid distance code";
! 1036: state->mode = BAD;
! 1037: break;
! 1038: }
! 1039: state->offset = (unsigned)this.val;
! 1040: state->extra = (unsigned)(this.op) & 15;
! 1041: state->mode = DISTEXT;
! 1042: /* FALL THROUGH */
! 1043: case DISTEXT:
! 1044: if (state->extra) {
! 1045: NEEDBITS(state->extra);
! 1046: state->offset += BITS(state->extra);
! 1047: DROPBITS(state->extra);
! 1048: }
! 1049: #ifdef INFLATE_STRICT
! 1050: if (state->offset > state->dmax) {
! 1051: strm->msg = (char *)"invalid distance too far back";
! 1052: state->mode = BAD;
! 1053: break;
! 1054: }
! 1055: #endif
! 1056: if (state->offset > state->whave + out - left) {
! 1057: strm->msg = (char *)"invalid distance too far back";
! 1058: state->mode = BAD;
! 1059: break;
! 1060: }
! 1061: Tracevv((stderr, "inflate: distance %u\n", state->offset));
! 1062: state->mode = MATCH;
! 1063: /* FALL THROUGH */
! 1064: case MATCH:
! 1065: if (left == 0) goto inf_leave;
! 1066: copy = out - left;
! 1067: if (state->offset > copy) { /* copy from window */
! 1068: copy = state->offset - copy;
! 1069: if (copy > state->write) {
! 1070: copy -= state->write;
! 1071: from = state->window + (state->wsize - copy);
! 1072: }
! 1073: else
! 1074: from = state->window + (state->write - copy);
! 1075: if (copy > state->length) copy = state->length;
! 1076: }
! 1077: else { /* copy from output */
! 1078: from = put - state->offset;
! 1079: copy = state->length;
! 1080: }
! 1081: if (copy > left) copy = left;
! 1082: left -= copy;
! 1083: state->length -= copy;
! 1084: do {
! 1085: *put++ = *from++;
! 1086: } while (--copy);
! 1087: if (state->length == 0) state->mode = LEN;
! 1088: break;
! 1089: case LIT:
! 1090: if (left == 0) goto inf_leave;
! 1091: *put++ = (unsigned char)(state->length);
! 1092: left--;
! 1093: state->mode = LEN;
! 1094: break;
! 1095: case CHECK:
! 1096: if (state->wrap) {
! 1097: NEEDBITS(32);
! 1098: out -= left;
! 1099: strm->total_out += out;
! 1100: state->total += out;
! 1101: if (out)
! 1102: strm->adler = state->check =
! 1103: UPDATE(state->check, put - out, out);
! 1104: out = left;
! 1105: if ((
! 1106: #ifdef GUNZIP
! 1107: state->flags ? hold :
! 1108: #endif
! 1109: REVERSE(hold)) != state->check) {
! 1110: strm->msg = (char *)"incorrect data check";
! 1111: state->mode = BAD;
! 1112: break;
! 1113: }
! 1114: INITBITS();
! 1115: Tracev((stderr, "inflate: check matches trailer\n"));
! 1116: }
! 1117: #ifdef GUNZIP
! 1118: state->mode = LENGTH;
! 1119: /* FALL THROUGH */
! 1120: case LENGTH:
! 1121: if (state->wrap && state->flags) {
! 1122: NEEDBITS(32);
! 1123: if (hold != (state->total & 0xffffffffUL)) {
! 1124: strm->msg = (char *)"incorrect length check";
! 1125: state->mode = BAD;
! 1126: break;
! 1127: }
! 1128: INITBITS();
! 1129: Tracev((stderr, "inflate: length matches trailer\n"));
! 1130: }
! 1131: #endif
! 1132: state->mode = DONE;
! 1133: /* FALL THROUGH */
! 1134: case DONE:
! 1135: ret = Z_STREAM_END;
! 1136: goto inf_leave;
! 1137: case BAD:
! 1138: ret = Z_DATA_ERROR;
! 1139: goto inf_leave;
! 1140: case MEM:
! 1141: return Z_MEM_ERROR;
! 1142: case SYNC:
! 1143: default:
! 1144: return Z_STREAM_ERROR;
! 1145: }
! 1146:
! 1147: /*
! 1148: Return from inflate(), updating the total counts and the check value.
! 1149: If there was no progress during the inflate() call, return a buffer
! 1150: error. Call updatewindow() to create and/or update the window state.
! 1151: Note: a memory error from inflate() is non-recoverable.
! 1152: */
! 1153: inf_leave:
! 1154: RESTORE();
! 1155: if (state->wsize || (state->mode < CHECK && out != strm->avail_out))
! 1156: if (updatewindow(strm, out)) {
! 1157: state->mode = MEM;
! 1158: return Z_MEM_ERROR;
! 1159: }
! 1160: in -= strm->avail_in;
! 1161: out -= strm->avail_out;
! 1162: strm->total_in += in;
! 1163: strm->total_out += out;
! 1164: state->total += out;
! 1165: if (state->wrap && out)
! 1166: strm->adler = state->check =
! 1167: UPDATE(state->check, strm->next_out - out, out);
! 1168: strm->data_type = state->bits + (state->last ? 64 : 0) +
! 1169: (state->mode == TYPE ? 128 : 0);
! 1170: if (((in == 0 && out == 0) || flush == Z_FINISH) && ret == Z_OK)
! 1171: ret = Z_BUF_ERROR;
! 1172: return ret;
! 1173: }
! 1174:
! 1175: int ZEXPORT inflateEnd(strm)
! 1176: z_streamp strm;
! 1177: {
! 1178: struct inflate_state FAR *state;
! 1179: if (strm == Z_NULL || strm->state == Z_NULL || strm->zfree == (free_func)0)
! 1180: return Z_STREAM_ERROR;
! 1181: state = (struct inflate_state FAR *)strm->state;
! 1182: if (state->window != Z_NULL) ZFREE(strm, state->window);
! 1183: ZFREE(strm, strm->state);
! 1184: strm->state = Z_NULL;
! 1185: Tracev((stderr, "inflate: end\n"));
! 1186: return Z_OK;
! 1187: }
! 1188:
! 1189: int ZEXPORT inflateSetDictionary(strm, dictionary, dictLength)
! 1190: z_streamp strm;
! 1191: const Bytef *dictionary;
! 1192: uInt dictLength;
! 1193: {
! 1194: struct inflate_state FAR *state;
! 1195: unsigned long id;
! 1196:
! 1197: /* check state */
! 1198: if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
! 1199: state = (struct inflate_state FAR *)strm->state;
! 1200: if (state->wrap != 0 && state->mode != DICT)
! 1201: return Z_STREAM_ERROR;
! 1202:
! 1203: /* check for correct dictionary id */
! 1204: if (state->mode == DICT) {
! 1205: id = adler32(0L, Z_NULL, 0);
! 1206: id = adler32(id, dictionary, dictLength);
! 1207: if (id != state->check)
! 1208: return Z_DATA_ERROR;
! 1209: }
! 1210:
! 1211: /* copy dictionary to window */
! 1212: if (updatewindow(strm, strm->avail_out)) {
! 1213: state->mode = MEM;
! 1214: return Z_MEM_ERROR;
! 1215: }
! 1216: if (dictLength > state->wsize) {
! 1217: zmemcpy(state->window, dictionary + dictLength - state->wsize,
! 1218: state->wsize);
! 1219: state->whave = state->wsize;
! 1220: }
! 1221: else {
! 1222: zmemcpy(state->window + state->wsize - dictLength, dictionary,
! 1223: dictLength);
! 1224: state->whave = dictLength;
! 1225: }
! 1226: state->havedict = 1;
! 1227: Tracev((stderr, "inflate: dictionary set\n"));
! 1228: return Z_OK;
! 1229: }
! 1230:
! 1231: int ZEXPORT inflateGetHeader(strm, head)
! 1232: z_streamp strm;
! 1233: gz_headerp head;
! 1234: {
! 1235: struct inflate_state FAR *state;
! 1236:
! 1237: /* check state */
! 1238: if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
! 1239: state = (struct inflate_state FAR *)strm->state;
! 1240: if ((state->wrap & 2) == 0) return Z_STREAM_ERROR;
! 1241:
! 1242: /* save header structure */
! 1243: state->head = head;
! 1244: head->done = 0;
! 1245: return Z_OK;
! 1246: }
! 1247:
! 1248: /*
! 1249: Search buf[0..len-1] for the pattern: 0, 0, 0xff, 0xff. Return when found
! 1250: or when out of input. When called, *have is the number of pattern bytes
! 1251: found in order so far, in 0..3. On return *have is updated to the new
! 1252: state. If on return *have equals four, then the pattern was found and the
! 1253: return value is how many bytes were read including the last byte of the
! 1254: pattern. If *have is less than four, then the pattern has not been found
! 1255: yet and the return value is len. In the latter case, syncsearch() can be
! 1256: called again with more data and the *have state. *have is initialized to
! 1257: zero for the first call.
! 1258: */
! 1259: local unsigned syncsearch(have, buf, len)
! 1260: unsigned FAR *have;
! 1261: unsigned char FAR *buf;
! 1262: unsigned len;
! 1263: {
! 1264: unsigned got;
! 1265: unsigned next;
! 1266:
! 1267: got = *have;
! 1268: next = 0;
! 1269: while (next < len && got < 4) {
! 1270: if ((int)(buf[next]) == (got < 2 ? 0 : 0xff))
! 1271: got++;
! 1272: else if (buf[next])
! 1273: got = 0;
! 1274: else
! 1275: got = 4 - got;
! 1276: next++;
! 1277: }
! 1278: *have = got;
! 1279: return next;
! 1280: }
! 1281:
! 1282: int ZEXPORT inflateSync(strm)
! 1283: z_streamp strm;
! 1284: {
! 1285: unsigned len; /* number of bytes to look at or looked at */
! 1286: unsigned long in, out; /* temporary to save total_in and total_out */
! 1287: unsigned char buf[4]; /* to restore bit buffer to byte string */
! 1288: struct inflate_state FAR *state;
! 1289:
! 1290: /* check parameters */
! 1291: if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
! 1292: state = (struct inflate_state FAR *)strm->state;
! 1293: if (strm->avail_in == 0 && state->bits < 8) return Z_BUF_ERROR;
! 1294:
! 1295: /* if first time, start search in bit buffer */
! 1296: if (state->mode != SYNC) {
! 1297: state->mode = SYNC;
! 1298: state->hold <<= state->bits & 7;
! 1299: state->bits -= state->bits & 7;
! 1300: len = 0;
! 1301: while (state->bits >= 8) {
! 1302: buf[len++] = (unsigned char)(state->hold);
! 1303: state->hold >>= 8;
! 1304: state->bits -= 8;
! 1305: }
! 1306: state->have = 0;
! 1307: syncsearch(&(state->have), buf, len);
! 1308: }
! 1309:
! 1310: /* search available input */
! 1311: len = syncsearch(&(state->have), strm->next_in, strm->avail_in);
! 1312: strm->avail_in -= len;
! 1313: strm->next_in += len;
! 1314: strm->total_in += len;
! 1315:
! 1316: /* return no joy or set up to restart inflate() on a new block */
! 1317: if (state->have != 4) return Z_DATA_ERROR;
! 1318: in = strm->total_in; out = strm->total_out;
! 1319: inflateReset(strm);
! 1320: strm->total_in = in; strm->total_out = out;
! 1321: state->mode = TYPE;
! 1322: return Z_OK;
! 1323: }
! 1324:
! 1325: /*
! 1326: Returns true if inflate is currently at the end of a block generated by
! 1327: Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP
! 1328: implementation to provide an additional safety check. PPP uses
! 1329: Z_SYNC_FLUSH but removes the length bytes of the resulting empty stored
! 1330: block. When decompressing, PPP checks that at the end of input packet,
! 1331: inflate is waiting for these length bytes.
! 1332: */
! 1333: int ZEXPORT inflateSyncPoint(strm)
! 1334: z_streamp strm;
! 1335: {
! 1336: struct inflate_state FAR *state;
! 1337:
! 1338: if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
! 1339: state = (struct inflate_state FAR *)strm->state;
! 1340: return state->mode == STORED && state->bits == 0;
! 1341: }
! 1342:
! 1343: int ZEXPORT inflateCopy(dest, source)
! 1344: z_streamp dest;
! 1345: z_streamp source;
! 1346: {
! 1347: struct inflate_state FAR *state;
! 1348: struct inflate_state FAR *copy;
! 1349: unsigned char FAR *window;
! 1350: unsigned wsize;
! 1351:
! 1352: /* check input */
! 1353: if (dest == Z_NULL || source == Z_NULL || source->state == Z_NULL ||
! 1354: source->zalloc == (alloc_func)0 || source->zfree == (free_func)0)
! 1355: return Z_STREAM_ERROR;
! 1356: state = (struct inflate_state FAR *)source->state;
! 1357:
! 1358: /* allocate space */
! 1359: copy = (struct inflate_state FAR *)
! 1360: ZALLOC(source, 1, sizeof(struct inflate_state));
! 1361: if (copy == Z_NULL) return Z_MEM_ERROR;
! 1362: window = Z_NULL;
! 1363: if (state->window != Z_NULL) {
! 1364: window = (unsigned char FAR *)
! 1365: ZALLOC(source, 1U << state->wbits, sizeof(unsigned char));
! 1366: if (window == Z_NULL) {
! 1367: ZFREE(source, copy);
! 1368: return Z_MEM_ERROR;
! 1369: }
! 1370: }
! 1371:
! 1372: /* copy state */
! 1373: zmemcpy(dest, source, sizeof(z_stream));
! 1374: zmemcpy(copy, state, sizeof(struct inflate_state));
! 1375: if (state->lencode >= state->codes &&
! 1376: state->lencode <= state->codes + ENOUGH - 1) {
! 1377: copy->lencode = copy->codes + (state->lencode - state->codes);
! 1378: copy->distcode = copy->codes + (state->distcode - state->codes);
! 1379: }
! 1380: copy->next = copy->codes + (state->next - state->codes);
! 1381: if (window != Z_NULL) {
! 1382: wsize = 1U << state->wbits;
! 1383: zmemcpy(window, state->window, wsize);
! 1384: }
! 1385: copy->window = window;
! 1386: dest->state = (struct internal_state FAR *)copy;
! 1387: return Z_OK;
! 1388: }
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