diff options
Diffstat (limited to 'src/zlib/inflate.c')
-rw-r--r-- | src/zlib/inflate.c | 1274 |
1 files changed, 0 insertions, 1274 deletions
diff --git a/src/zlib/inflate.c b/src/zlib/inflate.c deleted file mode 100644 index c6d38266d..000000000 --- a/src/zlib/inflate.c +++ /dev/null @@ -1,1274 +0,0 @@ -/* inflate.c -- zlib decompression - * Copyright (C) 1995-2003 Mark Adler - * For conditions of distribution and use, see copyright notice in zlib.h - */ - -/* - * Change history: - * - * 1.2.beta0 24 Nov 2002 - * - First version -- complete rewrite of inflate to simplify code, avoid - * creation of window when not needed, minimize use of window when it is - * needed, make inffast.c even faster, implement gzip decoding, and to - * improve code readability and style over the previous zlib inflate code - * - * 1.2.beta1 25 Nov 2002 - * - Use pointers for available input and output checking in inffast.c - * - Remove input and output counters in inffast.c - * - Change inffast.c entry and loop from avail_in >= 7 to >= 6 - * - Remove unnecessary second byte pull from length extra in inffast.c - * - Unroll direct copy to three copies per loop in inffast.c - * - * 1.2.beta2 4 Dec 2002 - * - Change external routine names to reduce potential conflicts - * - Correct filename to inffixed.h for fixed tables in inflate.c - * - Make hbuf[] unsigned char to match parameter type in inflate.c - * - Change strm->next_out[-state->offset] to *(strm->next_out - state->offset) - * to avoid negation problem on Alphas (64 bit) in inflate.c - * - * 1.2.beta3 22 Dec 2002 - * - Add comments on state->bits assertion in inffast.c - * - Add comments on op field in inftrees.h - * - Fix bug in reuse of allocated window after inflateReset() - * - Remove bit fields--back to byte structure for speed - * - Remove distance extra == 0 check in inflate_fast()--only helps for lengths - * - Change post-increments to pre-increments in inflate_fast(), PPC biased? - * - Add compile time option, POSTINC, to use post-increments instead (Intel?) - * - Make MATCH copy in inflate() much faster for when inflate_fast() not used - * - Use local copies of stream next and avail values, as well as local bit - * buffer and bit count in inflate()--for speed when inflate_fast() not used - * - * 1.2.beta4 1 Jan 2003 - * - Split ptr - 257 statements in inflate_table() to avoid compiler warnings - * - Move a comment on output buffer sizes from inffast.c to inflate.c - * - Add comments in inffast.c to introduce the inflate_fast() routine - * - Rearrange window copies in inflate_fast() for speed and simplification - * - Unroll last copy for window match in inflate_fast() - * - Use local copies of window variables in inflate_fast() for speed - * - Pull out common write == 0 case for speed in inflate_fast() - * - Make op and len in inflate_fast() unsigned for consistency - * - Add FAR to lcode and dcode declarations in inflate_fast() - * - Simplified bad distance check in inflate_fast() - * - Added inflateBackInit(), inflateBack(), and inflateBackEnd() in new - * source file infback.c to provide a call-back interface to inflate for - * programs like gzip and unzip -- uses window as output buffer to avoid - * window copying - * - * 1.2.beta5 1 Jan 2003 - * - Improved inflateBack() interface to allow the caller to provide initial - * input in strm. - * - Fixed stored blocks bug in inflateBack() - * - * 1.2.beta6 4 Jan 2003 - * - Added comments in inffast.c on effectiveness of POSTINC - * - Typecasting all around to reduce compiler warnings - * - Changed loops from while (1) or do {} while (1) to for (;;), again to - * make compilers happy - * - Changed type of window in inflateBackInit() to unsigned char * - * - * 1.2.beta7 27 Jan 2003 - * - Changed many types to unsigned or unsigned short to avoid warnings - * - Added inflateCopy() function - * - * 1.2.0 9 Mar 2003 - * - Changed inflateBack() interface to provide separate opaque descriptors - * for the in() and out() functions - * - Changed inflateBack() argument and in_func typedef to swap the length - * and buffer address return values for the input function - * - Check next_in and next_out for Z_NULL on entry to inflate() - * - * The history for versions after 1.2.0 are in ChangeLog in zlib distribution. - */ - -#include "zutil.h" -#include "inftrees.h" -#include "inflate.h" -#include "inffast.h" - -#ifdef MAKEFIXED -# ifndef BUILDFIXED -# define BUILDFIXED -# endif -#endif - -/* function prototypes */ -local void fixedtables OF((struct inflate_state FAR *state)); -local int updatewindow OF((z_streamp strm, unsigned out)); -#ifdef BUILDFIXED - void makefixed OF((void)); -#endif -local unsigned syncsearch OF((unsigned FAR *have, unsigned char FAR *buf, - unsigned len)); - -int ZEXPORT inflateReset(strm) -z_streamp strm; -{ - struct inflate_state FAR *state; - - if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; - state = (struct inflate_state FAR *)strm->state; - strm->total_in = strm->total_out = state->total = 0; - strm->msg = Z_NULL; - strm->adler = 1; /* to support ill-conceived Java test suite */ - state->mode = HEAD; - state->last = 0; - state->havedict = 0; - state->wsize = 0; - state->whave = 0; - state->hold = 0; - state->bits = 0; - state->lencode = state->distcode = state->next = state->codes; - Tracev((stderr, "inflate: reset\n")); - return Z_OK; -} - -int ZEXPORT inflateInit2_(strm, windowBits, version, stream_size) -z_streamp strm; -int windowBits; -const char *version; -int stream_size; -{ - struct inflate_state FAR *state; - - if (version == Z_NULL || version[0] != ZLIB_VERSION[0] || - stream_size != (int)(sizeof(z_stream))) - return Z_VERSION_ERROR; - if (strm == Z_NULL) return Z_STREAM_ERROR; - strm->msg = Z_NULL; /* in case we return an error */ - if (strm->zalloc == (alloc_func)0) { - strm->zalloc = zcalloc; - strm->opaque = (voidpf)0; - } - if (strm->zfree == (free_func)0) strm->zfree = zcfree; - state = (struct inflate_state FAR *) - ZALLOC(strm, 1, sizeof(struct inflate_state)); - if (state == Z_NULL) return Z_MEM_ERROR; - Tracev((stderr, "inflate: allocated\n")); - strm->state = (voidpf)state; - if (windowBits < 0) { - state->wrap = 0; - windowBits = -windowBits; - } - else { - state->wrap = (windowBits >> 4) + 1; -#ifdef GUNZIP - if (windowBits < 48) windowBits &= 15; -#endif - } - if (windowBits < 8 || windowBits > 15) { - ZFREE(strm, state); - strm->state = Z_NULL; - return Z_STREAM_ERROR; - } - state->wbits = (unsigned)windowBits; - state->window = Z_NULL; - return inflateReset(strm); -} - -int ZEXPORT inflateInit_(strm, version, stream_size) -z_streamp strm; -const char *version; -int stream_size; -{ - return inflateInit2_(strm, DEF_WBITS, version, stream_size); -} - -/* - Return state with length and distance decoding tables and index sizes set to - fixed code decoding. Normally this returns fixed tables from inffixed.h. - If BUILDFIXED is defined, then instead this routine builds the tables the - first time it's called, and returns those tables the first time and - thereafter. This reduces the size of the code by about 2K bytes, in - exchange for a little execution time. However, BUILDFIXED should not be - used for threaded applications, since the rewriting of the tables and virgin - may not be thread-safe. - */ -local void fixedtables(state) -struct inflate_state FAR *state; -{ -#ifdef BUILDFIXED - static int virgin = 1; - static code *lenfix, *distfix; - static code fixed[544]; - - /* build fixed huffman tables if first call (may not be thread safe) */ - if (virgin) { - unsigned sym, bits; - static code *next; - - /* literal/length table */ - sym = 0; - while (sym < 144) state->lens[sym++] = 8; - while (sym < 256) state->lens[sym++] = 9; - while (sym < 280) state->lens[sym++] = 7; - while (sym < 288) state->lens[sym++] = 8; - next = fixed; - lenfix = next; - bits = 9; - inflate_table(LENS, state->lens, 288, &(next), &(bits), state->work); - - /* distance table */ - sym = 0; - while (sym < 32) state->lens[sym++] = 5; - distfix = next; - bits = 5; - inflate_table(DISTS, state->lens, 32, &(next), &(bits), state->work); - - /* do this just once */ - virgin = 0; - } -#else /* !BUILDFIXED */ -# include "inffixed.h" -#endif /* BUILDFIXED */ - state->lencode = lenfix; - state->lenbits = 9; - state->distcode = distfix; - state->distbits = 5; -} - -#ifdef MAKEFIXED -#include <stdio.h> - -/* - Write out the inffixed.h that is #include'd above. Defining MAKEFIXED also - defines BUILDFIXED, so the tables are built on the fly. makefixed() writes - those tables to stdout, which would be piped to inffixed.h. A small program - can simply call makefixed to do this: - - void makefixed(void); - - int main(void) - { - makefixed(); - return 0; - } - - Then that can be linked with zlib built with MAKEFIXED defined and run: - - a.out > inffixed.h - */ -void makefixed() -{ - unsigned low, size; - struct inflate_state state; - - fixedtables(&state); - puts(" /* inffixed.h -- table for decoding fixed codes"); - puts(" * Generated automatically by makefixed()."); - puts(" */"); - puts(""); - puts(" /* WARNING: this file should *not* be used by applications."); - puts(" It is part of the implementation of this library and is"); - puts(" subject to change. Applications should only use zlib.h."); - puts(" */"); - puts(""); - size = 1U << 9; - printf(" static const code lenfix[%u] = {", size); - low = 0; - for (;;) { - if ((low % 7) == 0) printf("\n "); - printf("{%u,%u,%d}", state.lencode[low].op, state.lencode[low].bits, - state.lencode[low].val); - if (++low == size) break; - putchar(','); - } - puts("\n };"); - size = 1U << 5; - printf("\n static const code distfix[%u] = {", size); - low = 0; - for (;;) { - if ((low % 6) == 0) printf("\n "); - printf("{%u,%u,%d}", state.distcode[low].op, state.distcode[low].bits, - state.distcode[low].val); - if (++low == size) break; - putchar(','); - } - puts("\n };"); -} -#endif /* MAKEFIXED */ - -/* - Update the window with the last wsize (normally 32K) bytes written before - returning. If window does not exist yet, create it. This is only called - when a window is already in use, or when output has been written during this - inflate call, but the end of the deflate stream has not been reached yet. - It is also called to create a window for dictionary data when a dictionary - is loaded. - - Providing output buffers larger than 32K to inflate() should provide a speed - advantage, since only the last 32K of output is copied to the sliding window - upon return from inflate(), and since all distances after the first 32K of - output will fall in the output data, making match copies simpler and faster. - The advantage may be dependent on the size of the processor's data caches. - */ -local int updatewindow(strm, out) -z_streamp strm; -unsigned out; -{ - struct inflate_state FAR *state; - unsigned copy, dist; - - state = (struct inflate_state FAR *)strm->state; - - /* if it hasn't been done already, allocate space for the window */ - if (state->window == Z_NULL) { - state->window = (unsigned char FAR *) - ZALLOC(strm, 1U << state->wbits, - sizeof(unsigned char)); - if (state->window == Z_NULL) return 1; - } - - /* if window not in use yet, initialize */ - if (state->wsize == 0) { - state->wsize = 1U << state->wbits; - state->write = 0; - state->whave = 0; - } - - /* copy state->wsize or less output bytes into the circular window */ - copy = out - strm->avail_out; - if (copy >= state->wsize) { - zmemcpy(state->window, strm->next_out - state->wsize, state->wsize); - state->write = 0; - state->whave = state->wsize; - } - else { - dist = state->wsize - state->write; - if (dist > copy) dist = copy; - zmemcpy(state->window + state->write, strm->next_out - copy, dist); - copy -= dist; - if (copy) { - zmemcpy(state->window, strm->next_out - copy, copy); - state->write = copy; - state->whave = state->wsize; - } - else { - state->write += dist; - if (state->write == state->wsize) state->write = 0; - if (state->whave < state->wsize) state->whave += dist; - } - } - return 0; -} - -/* Macros for inflate(): */ - -/* check function to use adler32() for zlib or crc32() for gzip */ -#ifdef GUNZIP -# define UPDATE(check, buf, len) \ - (state->flags ? crc32(check, buf, len) : adler32(check, buf, len)) -#else -# define UPDATE(check, buf, len) adler32(check, buf, len) -#endif - -/* check macros for header crc */ -#ifdef GUNZIP -# define CRC2(check, word) \ - do { \ - hbuf[0] = (unsigned char)(word); \ - hbuf[1] = (unsigned char)((word) >> 8); \ - check = crc32(check, hbuf, 2); \ - } while (0) - -# define CRC4(check, word) \ - do { \ - hbuf[0] = (unsigned char)(word); \ - hbuf[1] = (unsigned char)((word) >> 8); \ - hbuf[2] = (unsigned char)((word) >> 16); \ - hbuf[3] = (unsigned char)((word) >> 24); \ - check = crc32(check, hbuf, 4); \ - } while (0) -#endif - -/* Load registers with state in inflate() for speed */ -#define LOAD() \ - do { \ - put = strm->next_out; \ - left = strm->avail_out; \ - next = strm->next_in; \ - have = strm->avail_in; \ - hold = state->hold; \ - bits = state->bits; \ - } while (0) - -/* Restore state from registers in inflate() */ -#define RESTORE() \ - do { \ - strm->next_out = put; \ - strm->avail_out = left; \ - strm->next_in = next; \ - strm->avail_in = have; \ - state->hold = hold; \ - state->bits = bits; \ - } while (0) - -/* Clear the input bit accumulator */ -#define INITBITS() \ - do { \ - hold = 0; \ - bits = 0; \ - } while (0) - -/* Get a byte of input into the bit accumulator, or return from inflate() - if there is no input available. */ -#define PULLBYTE() \ - do { \ - if (have == 0) goto inf_leave; \ - have--; \ - hold += (unsigned long)(*next++) << bits; \ - bits += 8; \ - } while (0) - -/* Assure that there are at least n bits in the bit accumulator. If there is - not enough available input to do that, then return from inflate(). */ -#define NEEDBITS(n) \ - do { \ - while (bits < (unsigned)(n)) \ - PULLBYTE(); \ - } while (0) - -/* Return the low n bits of the bit accumulator (n < 16) */ -#define BITS(n) \ - ((unsigned)hold & ((1U << (n)) - 1)) - -/* Remove n bits from the bit accumulator */ -#define DROPBITS(n) \ - do { \ - hold >>= (n); \ - bits -= (unsigned)(n); \ - } while (0) - -/* Remove zero to seven bits as needed to go to a byte boundary */ -#define BYTEBITS() \ - do { \ - hold >>= bits & 7; \ - bits -= bits & 7; \ - } while (0) - -/* Reverse the bytes in a 32-bit value */ -#define REVERSE(q) \ - ((((q) >> 24) & 0xff) + (((q) >> 8) & 0xff00) + \ - (((q) & 0xff00) << 8) + (((q) & 0xff) << 24)) - -/* - inflate() uses a state machine to process as much input data and generate as - much output data as possible before returning. The state machine is - structured roughly as follows: - - for (;;) switch (state) { - ... - case STATEn: - if (not enough input data or output space to make progress) - return; - ... make progress ... - state = STATEm; - break; - ... - } - - so when inflate() is called again, the same case is attempted again, and - if the appropriate resources are provided, the machine proceeds to the - next state. The NEEDBITS() macro is usually the way the state evaluates - whether it can proceed or should return. NEEDBITS() does the return if - the requested bits are not available. The typical use of the BITS macros - is: - - NEEDBITS(n); - ... do something with BITS(n) ... - DROPBITS(n); - - where NEEDBITS(n) either returns from inflate() if there isn't enough - input left to load n bits into the accumulator, or it continues. BITS(n) - gives the low n bits in the accumulator. When done, DROPBITS(n) drops - the low n bits off the accumulator. INITBITS() clears the accumulator - and sets the number of available bits to zero. BYTEBITS() discards just - enough bits to put the accumulator on a byte boundary. After BYTEBITS() - and a NEEDBITS(8), then BITS(8) would return the next byte in the stream. - - NEEDBITS(n) uses PULLBYTE() to get an available byte of input, or to return - if there is no input available. The decoding of variable length codes uses - PULLBYTE() directly in order to pull just enough bytes to decode the next - code, and no more. - - Some states loop until they get enough input, making sure that enough - state information is maintained to continue the loop where it left off - if NEEDBITS() returns in the loop. For example, want, need, and keep - would all have to actually be part of the saved state in case NEEDBITS() - returns: - - case STATEw: - while (want < need) { - NEEDBITS(n); - keep[want++] = BITS(n); - DROPBITS(n); - } - state = STATEx; - case STATEx: - - As shown above, if the next state is also the next case, then the break - is omitted. - - A state may also return if there is not enough output space available to - complete that state. Those states are copying stored data, writing a - literal byte, and copying a matching string. - - When returning, a "goto inf_leave" is used to update the total counters, - update the check value, and determine whether any progress has been made - during that inflate() call in order to return the proper return code. - Progress is defined as a change in either strm->avail_in or strm->avail_out. - When there is a window, goto inf_leave will update the window with the last - output written. If a goto inf_leave occurs in the middle of decompression - and there is no window currently, goto inf_leave will create one and copy - output to the window for the next call of inflate(). - - In this implementation, the flush parameter of inflate() only affects the - return code (per zlib.h). inflate() always writes as much as possible to - strm->next_out, given the space available and the provided input--the effect - documented in zlib.h of Z_SYNC_FLUSH. Furthermore, inflate() always defers - the allocation of and copying into a sliding window until necessary, which - provides the effect documented in zlib.h for Z_FINISH when the entire input - stream available. So the only thing the flush parameter actually does is: - when flush is set to Z_FINISH, inflate() cannot return Z_OK. Instead it - will return Z_BUF_ERROR if it has not reached the end of the stream. - */ - -int ZEXPORT inflate(strm, flush) -z_streamp strm; -int flush; -{ - struct inflate_state FAR *state; - unsigned char FAR *next; /* next input */ - unsigned char FAR *put; /* next output */ - unsigned have, left; /* available input and output */ - unsigned long hold; /* bit buffer */ - unsigned bits; /* bits in bit buffer */ - unsigned in, out; /* save starting available input and output */ - unsigned copy; /* number of stored or match bytes to copy */ - unsigned char FAR *from; /* where to copy match bytes from */ - code this; /* current decoding table entry */ - code last; /* parent table entry */ - unsigned len; /* length to copy for repeats, bits to drop */ - int ret; /* return code */ -#ifdef GUNZIP - unsigned char hbuf[4]; /* buffer for gzip header crc calculation */ -#endif - static const unsigned short order[19] = /* permutation of code lengths */ - {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}; - - if (strm == Z_NULL || strm->state == Z_NULL || strm->next_out == Z_NULL || - (strm->next_in == Z_NULL && strm->avail_in != 0)) - return Z_STREAM_ERROR; - - state = (struct inflate_state FAR *)strm->state; - if (state->mode == TYPE) state->mode = TYPEDO; /* skip check */ - LOAD(); - in = have; - out = left; - ret = Z_OK; - for (;;) - switch (state->mode) { - case HEAD: - if (state->wrap == 0) { - state->mode = TYPEDO; - break; - } - NEEDBITS(16); -#ifdef GUNZIP - if ((state->wrap & 2) && hold == 0x8b1f) { /* gzip header */ - state->check = crc32(0L, Z_NULL, 0); - CRC2(state->check, hold); - INITBITS(); - state->mode = FLAGS; - break; - } - state->flags = 0; /* expect zlib header */ - if (!(state->wrap & 1) || /* check if zlib header allowed */ -#else - if ( -#endif - ((BITS(8) << 8) + (hold >> 8)) % 31) { - strm->msg = (char *)"incorrect header check"; - state->mode = BAD; - break; - } - if (BITS(4) != Z_DEFLATED) { - strm->msg = (char *)"unknown compression method"; - state->mode = BAD; - break; - } - DROPBITS(4); - if (BITS(4) + 8 > state->wbits) { - strm->msg = (char *)"invalid window size"; - state->mode = BAD; - break; - } - Tracev((stderr, "inflate: zlib header ok\n")); - strm->adler = state->check = adler32(0L, Z_NULL, 0); - state->mode = hold & 0x200 ? DICTID : TYPE; - INITBITS(); - break; -#ifdef GUNZIP - case FLAGS: - NEEDBITS(16); - state->flags = (int)(hold); - if ((state->flags & 0xff) != Z_DEFLATED) { - strm->msg = (char *)"unknown compression method"; - state->mode = BAD; - break; - } - if (state->flags & 0xe000) { - strm->msg = (char *)"unknown header flags set"; - state->mode = BAD; - break; - } - if (state->flags & 0x0200) CRC2(state->check, hold); - INITBITS(); - state->mode = TIME; - case TIME: - NEEDBITS(32); - if (state->flags & 0x0200) CRC4(state->check, hold); - INITBITS(); - state->mode = OS; - case OS: - NEEDBITS(16); - if (state->flags & 0x0200) CRC2(state->check, hold); - INITBITS(); - state->mode = EXLEN; - case EXLEN: - if (state->flags & 0x0400) { - NEEDBITS(16); - state->length = (unsigned)(hold); - if (state->flags & 0x0200) CRC2(state->check, hold); - INITBITS(); - } - state->mode = EXTRA; - case EXTRA: - if (state->flags & 0x0400) { - copy = state->length; - if (copy > have) copy = have; - if (copy) { - if (state->flags & 0x0200) - state->check = crc32(state->check, next, copy); - have -= copy; - next += copy; - state->length -= copy; - } - if (state->length) goto inf_leave; - } - state->mode = NAME; - case NAME: - if (state->flags & 0x0800) { - if (have == 0) goto inf_leave; - copy = 0; - do { - len = (unsigned)(next[copy++]); - } while (len && copy < have); - if (state->flags & 0x02000) - state->check = crc32(state->check, next, copy); - have -= copy; - next += copy; - if (len) goto inf_leave; - } - state->mode = COMMENT; - case COMMENT: - if (state->flags & 0x1000) { - if (have == 0) goto inf_leave; - copy = 0; - do { - len = (unsigned)(next[copy++]); - } while (len && copy < have); - if (state->flags & 0x02000) - state->check = crc32(state->check, next, copy); - have -= copy; - next += copy; - if (len) goto inf_leave; - } - state->mode = HCRC; - case HCRC: - if (state->flags & 0x0200) { - NEEDBITS(16); - if (hold != (state->check & 0xffff)) { - strm->msg = (char *)"header crc mismatch"; - state->mode = BAD; - break; - } - INITBITS(); - } - strm->adler = state->check = crc32(0L, Z_NULL, 0); - state->mode = TYPE; - break; -#endif - case DICTID: - NEEDBITS(32); - strm->adler = state->check = REVERSE(hold); - INITBITS(); - state->mode = DICT; - case DICT: - if (state->havedict == 0) { - RESTORE(); - return Z_NEED_DICT; - } - strm->adler = state->check = adler32(0L, Z_NULL, 0); - state->mode = TYPE; - case TYPE: - if (flush == Z_BLOCK) goto inf_leave; - case TYPEDO: - if (state->last) { - BYTEBITS(); - state->mode = CHECK; - break; - } - NEEDBITS(3); - state->last = BITS(1); - DROPBITS(1); - switch (BITS(2)) { - case 0: /* stored block */ - Tracev((stderr, "inflate: stored block%s\n", - state->last ? " (last)" : "")); - state->mode = STORED; - break; - case 1: /* fixed block */ - fixedtables(state); - Tracev((stderr, "inflate: fixed codes block%s\n", - state->last ? " (last)" : "")); - state->mode = LEN; /* decode codes */ - break; - case 2: /* dynamic block */ - Tracev((stderr, "inflate: dynamic codes block%s\n", - state->last ? " (last)" : "")); - state->mode = TABLE; - break; - case 3: - strm->msg = (char *)"invalid block type"; - state->mode = BAD; - } - DROPBITS(2); - break; - case STORED: - BYTEBITS(); /* go to byte boundary */ - NEEDBITS(32); - if ((hold & 0xffff) != ((hold >> 16) ^ 0xffff)) { - strm->msg = (char *)"invalid stored block lengths"; - state->mode = BAD; - break; - } - state->length = (unsigned)hold & 0xffff; - Tracev((stderr, "inflate: stored length %u\n", - state->length)); - INITBITS(); - state->mode = COPY; - case COPY: - copy = state->length; - if (copy) { - if (copy > have) copy = have; - if (copy > left) copy = left; - if (copy == 0) goto inf_leave; - zmemcpy(put, next, copy); - have -= copy; - next += copy; - left -= copy; - put += copy; - state->length -= copy; - break; - } - Tracev((stderr, "inflate: stored end\n")); - state->mode = TYPE; - break; - case TABLE: - NEEDBITS(14); - state->nlen = BITS(5) + 257; - DROPBITS(5); - state->ndist = BITS(5) + 1; - DROPBITS(5); - state->ncode = BITS(4) + 4; - DROPBITS(4); -#ifndef PKZIP_BUG_WORKAROUND - if (state->nlen > 286 || state->ndist > 30) { - strm->msg = (char *)"too many length or distance symbols"; - state->mode = BAD; - break; - } -#endif - Tracev((stderr, "inflate: table sizes ok\n")); - state->have = 0; - state->mode = LENLENS; - case LENLENS: - while (state->have < state->ncode) { - NEEDBITS(3); - state->lens[order[state->have++]] = (unsigned short)BITS(3); - DROPBITS(3); - } - while (state->have < 19) - state->lens[order[state->have++]] = 0; - state->next = state->codes; - state->lencode = (code const FAR *)(state->next); - state->lenbits = 7; - ret = inflate_table(CODES, state->lens, 19, &(state->next), - &(state->lenbits), state->work); - if (ret) { - strm->msg = (char *)"invalid code lengths set"; - state->mode = BAD; - break; - } - Tracev((stderr, "inflate: code lengths ok\n")); - state->have = 0; - state->mode = CODELENS; - case CODELENS: - while (state->have < state->nlen + state->ndist) { - for (;;) { - this = state->lencode[BITS(state->lenbits)]; - if ((unsigned)(this.bits) <= bits) break; - PULLBYTE(); - } - if (this.val < 16) { - NEEDBITS(this.bits); - DROPBITS(this.bits); - state->lens[state->have++] = this.val; - } - else { - if (this.val == 16) { - NEEDBITS(this.bits + 2); - DROPBITS(this.bits); - if (state->have == 0) { - strm->msg = (char *)"invalid bit length repeat"; - state->mode = BAD; - break; - } - len = state->lens[state->have - 1]; - copy = 3 + BITS(2); - DROPBITS(2); - } - else if (this.val == 17) { - NEEDBITS(this.bits + 3); - DROPBITS(this.bits); - len = 0; - copy = 3 + BITS(3); - DROPBITS(3); - } - else { - NEEDBITS(this.bits + 7); - DROPBITS(this.bits); - len = 0; - copy = 11 + BITS(7); - DROPBITS(7); - } - if (state->have + copy > state->nlen + state->ndist) { - strm->msg = (char *)"invalid bit length repeat"; - state->mode = BAD; - break; - } - while (copy--) - state->lens[state->have++] = (unsigned short)len; - } - } - - /* handle error breaks in while */ - if (state->mode == BAD) break; - - /* build code tables */ - state->next = state->codes; - state->lencode = (code const FAR *)(state->next); - state->lenbits = 9; - ret = inflate_table(LENS, state->lens, state->nlen, &(state->next), - &(state->lenbits), state->work); - if (ret) { - strm->msg = (char *)"invalid literal/lengths set"; - state->mode = BAD; - break; - } - state->distcode = (code const FAR *)(state->next); - state->distbits = 6; - ret = inflate_table(DISTS, state->lens + state->nlen, state->ndist, - &(state->next), &(state->distbits), state->work); - if (ret) { - strm->msg = (char *)"invalid distances set"; - state->mode = BAD; - break; - } - Tracev((stderr, "inflate: codes ok\n")); - state->mode = LEN; - case LEN: - if (have >= 6 && left >= 258) { - RESTORE(); - inflate_fast(strm, out); - LOAD(); - break; - } - for (;;) { - this = state->lencode[BITS(state->lenbits)]; - if ((unsigned)(this.bits) <= bits) break; - PULLBYTE(); - } - if (this.op && (this.op & 0xf0) == 0) { - last = this; - for (;;) { - this = state->lencode[last.val + - (BITS(last.bits + last.op) >> last.bits)]; - if ((unsigned)(last.bits + this.bits) <= bits) break; - PULLBYTE(); - } - DROPBITS(last.bits); - } - DROPBITS(this.bits); - state->length = (unsigned)this.val; - if ((int)(this.op) == 0) { - Tracevv((stderr, this.val >= 0x20 && this.val < 0x7f ? - "inflate: literal '%c'\n" : - "inflate: literal 0x%02x\n", this.val)); - state->mode = LIT; - break; - } - if (this.op & 32) { - Tracevv((stderr, "inflate: end of block\n")); - state->mode = TYPE; - break; - } - if (this.op & 64) { - strm->msg = (char *)"invalid literal/length code"; - state->mode = BAD; - break; - } - state->extra = (unsigned)(this.op) & 15; - state->mode = LENEXT; - case LENEXT: - if (state->extra) { - NEEDBITS(state->extra); - state->length += BITS(state->extra); - DROPBITS(state->extra); - } - Tracevv((stderr, "inflate: length %u\n", state->length)); - state->mode = DIST; - case DIST: - for (;;) { - this = state->distcode[BITS(state->distbits)]; - if ((unsigned)(this.bits) <= bits) break; - PULLBYTE(); - } - if ((this.op & 0xf0) == 0) { - last = this; - for (;;) { - this = state->distcode[last.val + - (BITS(last.bits + last.op) >> last.bits)]; - if ((unsigned)(last.bits + this.bits) <= bits) break; - PULLBYTE(); - } - DROPBITS(last.bits); - } - DROPBITS(this.bits); - if (this.op & 64) { - strm->msg = (char *)"invalid distance code"; - state->mode = BAD; - break; - } - state->offset = (unsigned)this.val; - state->extra = (unsigned)(this.op) & 15; - state->mode = DISTEXT; - case DISTEXT: - if (state->extra) { - NEEDBITS(state->extra); - state->offset += BITS(state->extra); - DROPBITS(state->extra); - } - if (state->offset > state->whave + out - left) { - strm->msg = (char *)"invalid distance too far back"; - state->mode = BAD; - break; - } - Tracevv((stderr, "inflate: distance %u\n", state->offset)); - state->mode = MATCH; - case MATCH: - if (left == 0) goto inf_leave; - copy = out - left; - if (state->offset > copy) { /* copy from window */ - copy = state->offset - copy; - if (copy > state->write) { - copy -= state->write; - from = state->window + (state->wsize - copy); - } - else - from = state->window + (state->write - copy); - if (copy > state->length) copy = state->length; - } - else { /* copy from output */ - from = put - state->offset; - copy = state->length; - } - if (copy > left) copy = left; - left -= copy; - state->length -= copy; - do { - *put++ = *from++; - } while (--copy); - if (state->length == 0) state->mode = LEN; - break; - case LIT: - if (left == 0) goto inf_leave; - *put++ = (unsigned char)(state->length); - left--; - state->mode = LEN; - break; - case CHECK: - if (state->wrap) { - NEEDBITS(32); - out -= left; - strm->total_out += out; - state->total += out; - if (out) - strm->adler = state->check = - UPDATE(state->check, put - out, out); - out = left; - if (( -#ifdef GUNZIP - state->flags ? hold : -#endif - REVERSE(hold)) != state->check) { - strm->msg = (char *)"incorrect data check"; - state->mode = BAD; - break; - } - INITBITS(); - Tracev((stderr, "inflate: check matches trailer\n")); - } -#ifdef GUNZIP - state->mode = LENGTH; - case LENGTH: - if (state->wrap && state->flags) { - NEEDBITS(32); - if (hold != (state->total & 0xffffffffUL)) { - strm->msg = (char *)"incorrect length check"; - state->mode = BAD; - break; - } - INITBITS(); - Tracev((stderr, "inflate: length matches trailer\n")); - } -#endif - state->mode = DONE; - case DONE: - ret = Z_STREAM_END; - goto inf_leave; - case BAD: - ret = Z_DATA_ERROR; - goto inf_leave; - case MEM: - return Z_MEM_ERROR; - case SYNC: - default: - return Z_STREAM_ERROR; - } - - /* - Return from inflate(), updating the total counts and the check value. - If there was no progress during the inflate() call, return a buffer - error. Call updatewindow() to create and/or update the window state. - Note: a memory error from inflate() is non-recoverable. - */ - inf_leave: - RESTORE(); - if (state->wsize || (state->mode < CHECK && out != strm->avail_out)) - if (updatewindow(strm, out)) { - state->mode = MEM; - return Z_MEM_ERROR; - } - in -= strm->avail_in; - out -= strm->avail_out; - strm->total_in += in; - strm->total_out += out; - state->total += out; - if (state->wrap && out) - strm->adler = state->check = - UPDATE(state->check, strm->next_out - out, out); - strm->data_type = state->bits + (state->last ? 64 : 0) + - (state->mode == TYPE ? 128 : 0); - if (((in == 0 && out == 0) || flush == Z_FINISH) && ret == Z_OK) - ret = Z_BUF_ERROR; - return ret; -} - -int ZEXPORT inflateEnd(strm) -z_streamp strm; -{ - struct inflate_state FAR *state; - if (strm == Z_NULL || strm->state == Z_NULL || strm->zfree == (free_func)0) - return Z_STREAM_ERROR; - state = (struct inflate_state FAR *)strm->state; - if (state->window != Z_NULL) ZFREE(strm, state->window); - ZFREE(strm, strm->state); - strm->state = Z_NULL; - Tracev((stderr, "inflate: end\n")); - return Z_OK; -} - -int ZEXPORT inflateSetDictionary(strm, dictionary, dictLength) -z_streamp strm; -const Bytef *dictionary; -uInt dictLength; -{ - struct inflate_state FAR *state; - unsigned long id; - - /* check state */ - if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; - state = (struct inflate_state FAR *)strm->state; - if (state->mode != DICT) return Z_STREAM_ERROR; - - /* check for correct dictionary id */ - id = adler32(0L, Z_NULL, 0); - id = adler32(id, dictionary, dictLength); - if (id != state->check) return Z_DATA_ERROR; - - /* copy dictionary to window */ - if (updatewindow(strm, strm->avail_out)) { - state->mode = MEM; - return Z_MEM_ERROR; - } - if (dictLength > state->wsize) { - zmemcpy(state->window, dictionary + dictLength - state->wsize, - state->wsize); - state->whave = state->wsize; - } - else { - zmemcpy(state->window + state->wsize - dictLength, dictionary, - dictLength); - state->whave = dictLength; - } - state->havedict = 1; - Tracev((stderr, "inflate: dictionary set\n")); - return Z_OK; -} - -/* - Search buf[0..len-1] for the pattern: 0, 0, 0xff, 0xff. Return when found - or when out of input. When called, *have is the number of pattern bytes - found in order so far, in 0..3. On return *have is updated to the new - state. If on return *have equals four, then the pattern was found and the - return value is how many bytes were read including the last byte of the - pattern. If *have is less than four, then the pattern has not been found - yet and the return value is len. In the latter case, syncsearch() can be - called again with more data and the *have state. *have is initialized to - zero for the first call. - */ -local unsigned syncsearch(have, buf, len) -unsigned FAR *have; -unsigned char FAR *buf; -unsigned len; -{ - unsigned got; - unsigned next; - - got = *have; - next = 0; - while (next < len && got < 4) { - if ((int)(buf[next]) == (got < 2 ? 0 : 0xff)) - got++; - else if (buf[next]) - got = 0; - else - got = 4 - got; - next++; - } - *have = got; - return next; -} - -int ZEXPORT inflateSync(strm) -z_streamp strm; -{ - unsigned len; /* number of bytes to look at or looked at */ - unsigned long in, out; /* temporary to save total_in and total_out */ - unsigned char buf[4]; /* to restore bit buffer to byte string */ - struct inflate_state FAR *state; - - /* check parameters */ - if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; - state = (struct inflate_state FAR *)strm->state; - if (strm->avail_in == 0 && state->bits < 8) return Z_BUF_ERROR; - - /* if first time, start search in bit buffer */ - if (state->mode != SYNC) { - state->mode = SYNC; - state->hold <<= state->bits & 7; - state->bits -= state->bits & 7; - len = 0; - while (state->bits >= 8) { - buf[len++] = (unsigned char)(state->hold); - state->hold >>= 8; - state->bits -= 8; - } - state->have = 0; - syncsearch(&(state->have), buf, len); - } - - /* search available input */ - len = syncsearch(&(state->have), strm->next_in, strm->avail_in); - strm->avail_in -= len; - strm->next_in += len; - strm->total_in += len; - - /* return no joy or set up to restart inflate() on a new block */ - if (state->have != 4) return Z_DATA_ERROR; - in = strm->total_in; out = strm->total_out; - inflateReset(strm); - strm->total_in = in; strm->total_out = out; - state->mode = TYPE; - return Z_OK; -} - -/* - Returns true if inflate is currently at the end of a block generated by - Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP - implementation to provide an additional safety check. PPP uses - Z_SYNC_FLUSH but removes the length bytes of the resulting empty stored - block. When decompressing, PPP checks that at the end of input packet, - inflate is waiting for these length bytes. - */ -int ZEXPORT inflateSyncPoint(strm) -z_streamp strm; -{ - struct inflate_state FAR *state; - - if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; - state = (struct inflate_state FAR *)strm->state; - return state->mode == STORED && state->bits == 0; -} - -int ZEXPORT inflateCopy(dest, source) -z_streamp dest; -z_streamp source; -{ - struct inflate_state FAR *state; - struct inflate_state FAR *copy; - unsigned char FAR *window; - - /* check input */ - if (dest == Z_NULL || source == Z_NULL || source->state == Z_NULL || - source->zalloc == (alloc_func)0 || source->zfree == (free_func)0) - return Z_STREAM_ERROR; - state = (struct inflate_state FAR *)source->state; - - /* allocate space */ - copy = (struct inflate_state FAR *) - ZALLOC(source, 1, sizeof(struct inflate_state)); - if (copy == Z_NULL) return Z_MEM_ERROR; - window = Z_NULL; - if (state->window != Z_NULL) { - window = (unsigned char FAR *) - ZALLOC(source, 1U << state->wbits, sizeof(unsigned char)); - if (window == Z_NULL) { - ZFREE(source, copy); - return Z_MEM_ERROR; - } - } - - /* copy state */ - *dest = *source; - *copy = *state; - copy->lencode = copy->codes + (state->lencode - state->codes); - copy->distcode = copy->codes + (state->distcode - state->codes); - copy->next = copy->codes + (state->next - state->codes); - if (window != Z_NULL) - zmemcpy(window, state->window, 1U << state->wbits); - copy->window = window; - dest->state = (voidpf)copy; - return Z_OK; -} |