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| author | Remko Tronçon <git@el-tramo.be> | 2009-06-01 08:48:42 (GMT) | 
|---|---|---|
| committer | Remko Tronçon <git@el-tramo.be> | 2009-06-01 09:24:28 (GMT) | 
| commit | 2812bddd81f8a1b804c7460f4e14cd0aa393d129 (patch) | |
| tree | d46294f35150c4f0f43deaf2d31fceaf945ae715 /3rdParty/ZLib/src/inflate.c | |
| download | swift-2812bddd81f8a1b804c7460f4e14cd0aa393d129.zip swift-2812bddd81f8a1b804c7460f4e14cd0aa393d129.tar.bz2  | |
Import.
Diffstat (limited to '3rdParty/ZLib/src/inflate.c')
| -rw-r--r-- | 3rdParty/ZLib/src/inflate.c | 1368 | 
1 files changed, 1368 insertions, 0 deletions
diff --git a/3rdParty/ZLib/src/inflate.c b/3rdParty/ZLib/src/inflate.c new file mode 100644 index 0000000..792fdee --- /dev/null +++ b/3rdParty/ZLib/src/inflate.c @@ -0,0 +1,1368 @@ +/* inflate.c -- zlib decompression + * Copyright (C) 1995-2005 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->dmax = 32768U; +    state->head = Z_NULL; +    state->wsize = 0; +    state->whave = 0; +    state->write = 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 inflatePrime(strm, bits, value) +z_streamp strm; +int bits; +int value; +{ +    struct inflate_state FAR *state; + +    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; +    state = (struct inflate_state FAR *)strm->state; +    if (bits > 16 || state->bits + bits > 32) return Z_STREAM_ERROR; +    value &= (1L << bits) - 1; +    state->hold += value << state->bits; +    state->bits += bits; +    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 = (struct internal_state FAR *)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->head != Z_NULL) +                state->head->done = -1; +            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); +            len = BITS(4) + 8; +            if (len > state->wbits) { +                strm->msg = (char *)"invalid window size"; +                state->mode = BAD; +                break; +            } +            state->dmax = 1U << len; +            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->head != Z_NULL) +                state->head->text = (int)((hold >> 8) & 1); +            if (state->flags & 0x0200) CRC2(state->check, hold); +            INITBITS(); +            state->mode = TIME; +        case TIME: +            NEEDBITS(32); +            if (state->head != Z_NULL) +                state->head->time = hold; +            if (state->flags & 0x0200) CRC4(state->check, hold); +            INITBITS(); +            state->mode = OS; +        case OS: +            NEEDBITS(16); +            if (state->head != Z_NULL) { +                state->head->xflags = (int)(hold & 0xff); +                state->head->os = (int)(hold >> 8); +            } +            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->head != Z_NULL) +                    state->head->extra_len = (unsigned)hold; +                if (state->flags & 0x0200) CRC2(state->check, hold); +                INITBITS(); +            } +            else if (state->head != Z_NULL) +                state->head->extra = Z_NULL; +            state->mode = EXTRA; +        case EXTRA: +            if (state->flags & 0x0400) { +                copy = state->length; +                if (copy > have) copy = have; +                if (copy) { +                    if (state->head != Z_NULL && +                        state->head->extra != Z_NULL) { +                        len = state->head->extra_len - state->length; +                        zmemcpy(state->head->extra + len, next, +                                len + copy > state->head->extra_max ? +                                state->head->extra_max - len : 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->length = 0; +            state->mode = NAME; +        case NAME: +            if (state->flags & 0x0800) { +                if (have == 0) goto inf_leave; +                copy = 0; +                do { +                    len = (unsigned)(next[copy++]); +                    if (state->head != Z_NULL && +                            state->head->name != Z_NULL && +                            state->length < state->head->name_max) +                        state->head->name[state->length++] = len; +                } while (len && copy < have); +                if (state->flags & 0x0200) +                    state->check = crc32(state->check, next, copy); +                have -= copy; +                next += copy; +                if (len) goto inf_leave; +            } +            else if (state->head != Z_NULL) +                state->head->name = Z_NULL; +            state->length = 0; +            state->mode = COMMENT; +        case COMMENT: +            if (state->flags & 0x1000) { +                if (have == 0) goto inf_leave; +                copy = 0; +                do { +                    len = (unsigned)(next[copy++]); +                    if (state->head != Z_NULL && +                            state->head->comment != Z_NULL && +                            state->length < state->head->comm_max) +                        state->head->comment[state->length++] = len; +                } while (len && copy < have); +                if (state->flags & 0x0200) +                    state->check = crc32(state->check, next, copy); +                have -= copy; +                next += copy; +                if (len) goto inf_leave; +            } +            else if (state->head != Z_NULL) +                state->head->comment = Z_NULL; +            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(); +            } +            if (state->head != Z_NULL) { +                state->head->hcrc = (int)((state->flags >> 9) & 1); +                state->head->done = 1; +            } +            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); +            } +#ifdef INFLATE_STRICT +            if (state->offset > state->dmax) { +                strm->msg = (char *)"invalid distance too far back"; +                state->mode = BAD; +                break; +            } +#endif +            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->wrap != 0 && state->mode != DICT) +        return Z_STREAM_ERROR; + +    /* check for correct dictionary id */ +    if (state->mode == DICT) { +        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; +} + +int ZEXPORT inflateGetHeader(strm, head) +z_streamp strm; +gz_headerp head; +{ +    struct inflate_state FAR *state; + +    /* check state */ +    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; +    state = (struct inflate_state FAR *)strm->state; +    if ((state->wrap & 2) == 0) return Z_STREAM_ERROR; + +    /* save header structure */ +    state->head = head; +    head->done = 0; +    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; +    unsigned wsize; + +    /* 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 */ +    zmemcpy(dest, source, sizeof(z_stream)); +    zmemcpy(copy, state, sizeof(struct inflate_state)); +    if (state->lencode >= state->codes && +        state->lencode <= state->codes + ENOUGH - 1) { +        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) { +        wsize = 1U << state->wbits; +        zmemcpy(window, state->window, wsize); +    } +    copy->window = window; +    dest->state = (struct internal_state FAR *)copy; +    return Z_OK; +}  | 
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