/* 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;+
−
}+
−