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d483eb21cf
Signed-off-by: Jacek Caban <jacek@codeweavers.com> Signed-off-by: Alexandre Julliard <julliard@winehq.org>
1916 lines
75 KiB
C
1916 lines
75 KiB
C
/* inflate.c -- zlib decompression
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*
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* Copyright (C) 1995-2017 Jean-loup Gailly and Mark Adler
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*
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* This software is provided 'as-is', without any express or implied
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* warranty. In no event will the authors be held liable for any damages
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* arising from the use of this software.
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*
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* Permission is granted to anyone to use this software for any purpose,
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* including commercial applications, and to alter it and redistribute it
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* freely, subject to the following restrictions:
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*
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* 1. The origin of this software must not be misrepresented; you must not
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* claim that you wrote the original software. If you use this software
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* in a product, an acknowledgment in the product documentation would be
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* appreciated but is not required.
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* 2. Altered source versions must be plainly marked as such, and must not be
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* misrepresented as being the original software.
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* 3. This notice may not be removed or altered from any source distribution.
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*
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* Jean-loup Gailly Mark Adler
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* jloup@gzip.org madler@alumni.caltech.edu
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*/
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#include <stdarg.h>
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#include <stdlib.h>
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#include <string.h>
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#include <limits.h>
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#include "winternl.h"
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#include "zlib.h"
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#define DEF_WBITS MAX_WBITS
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#define zmemcpy memcpy
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#define zmemzero(dest, len) memset(dest, 0, len)
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#define Assert(cond,msg)
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#define Trace(x)
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#define Tracev(x)
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#define Tracevv(x)
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#define Tracecv(c,x)
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#define GUNZIP
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#define ZALLOC(strm, items, size) \
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(*((strm)->zalloc))((strm)->opaque, (items), (size))
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#define ZFREE(strm, addr) (*((strm)->zfree))((strm)->opaque, (voidpf)(addr))
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#define TRY_FREE(s, p) {if (p) ZFREE(s, p);}
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/* Reverse the bytes in a 32-bit value */
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#define ZSWAP32(q) ((((q) >> 24) & 0xff) + (((q) >> 8) & 0xff00) + \
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(((q) & 0xff00) << 8) + (((q) & 0xff) << 24))
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#define BASE 65521U /* largest prime smaller than 65536 */
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#define NMAX 5552
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/* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
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#define DO1(buf,i) {adler += (buf)[i]; sum2 += adler;}
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#define DO2(buf,i) DO1(buf,i); DO1(buf,i+1);
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#define DO4(buf,i) DO2(buf,i); DO2(buf,i+2);
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#define DO8(buf,i) DO4(buf,i); DO4(buf,i+4);
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#define DO16(buf) DO8(buf,0); DO8(buf,8);
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#define MOD(a) a %= BASE
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#define MOD28(a) a %= BASE
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#define MOD63(a) a %= BASE
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static uLong adler32( uLong adler, const Bytef *buf, uInt len )
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{
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unsigned long sum2;
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unsigned n;
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/* split Adler-32 into component sums */
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sum2 = (adler >> 16) & 0xffff;
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adler &= 0xffff;
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/* in case user likes doing a byte at a time, keep it fast */
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if (len == 1) {
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adler += buf[0];
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if (adler >= BASE)
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adler -= BASE;
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sum2 += adler;
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if (sum2 >= BASE)
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sum2 -= BASE;
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return adler | (sum2 << 16);
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}
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/* initial Adler-32 value (deferred check for len == 1 speed) */
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if (buf == Z_NULL)
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return 1L;
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/* in case short lengths are provided, keep it somewhat fast */
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if (len < 16) {
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while (len--) {
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adler += *buf++;
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sum2 += adler;
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}
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if (adler >= BASE)
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adler -= BASE;
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MOD28(sum2); /* only added so many BASE's */
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return adler | (sum2 << 16);
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}
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/* do length NMAX blocks -- requires just one modulo operation */
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while (len >= NMAX) {
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len -= NMAX;
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n = NMAX / 16; /* NMAX is divisible by 16 */
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do {
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DO16(buf); /* 16 sums unrolled */
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buf += 16;
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} while (--n);
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MOD(adler);
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MOD(sum2);
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}
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/* do remaining bytes (less than NMAX, still just one modulo) */
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if (len) { /* avoid modulos if none remaining */
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while (len >= 16) {
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len -= 16;
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DO16(buf);
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buf += 16;
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}
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while (len--) {
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adler += *buf++;
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sum2 += adler;
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}
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MOD(adler);
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MOD(sum2);
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}
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/* return recombined sums */
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return adler | (sum2 << 16);
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}
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typedef struct {
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unsigned char op; /* operation, extra bits, table bits */
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unsigned char bits; /* bits in this part of the code */
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unsigned short val; /* offset in table or code value */
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} code;
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#define ENOUGH_LENS 852
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#define ENOUGH_DISTS 592
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#define ENOUGH (ENOUGH_LENS+ENOUGH_DISTS)
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/* Type of code to build for inflate_table() */
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typedef enum {
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CODES,
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LENS,
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DISTS
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} codetype;
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/* Possible inflate modes between inflate() calls */
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typedef enum {
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HEAD = 16180, /* i: waiting for magic header */
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FLAGS, /* i: waiting for method and flags (gzip) */
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TIME, /* i: waiting for modification time (gzip) */
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OS, /* i: waiting for extra flags and operating system (gzip) */
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EXLEN, /* i: waiting for extra length (gzip) */
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EXTRA, /* i: waiting for extra bytes (gzip) */
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NAME, /* i: waiting for end of file name (gzip) */
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COMMENT, /* i: waiting for end of comment (gzip) */
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HCRC, /* i: waiting for header crc (gzip) */
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DICTID, /* i: waiting for dictionary check value */
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DICT, /* waiting for inflateSetDictionary() call */
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TYPE, /* i: waiting for type bits, including last-flag bit */
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TYPEDO, /* i: same, but skip check to exit inflate on new block */
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STORED, /* i: waiting for stored size (length and complement) */
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COPY_, /* i/o: same as COPY below, but only first time in */
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COPY, /* i/o: waiting for input or output to copy stored block */
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TABLE, /* i: waiting for dynamic block table lengths */
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LENLENS, /* i: waiting for code length code lengths */
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CODELENS, /* i: waiting for length/lit and distance code lengths */
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LEN_, /* i: same as LEN below, but only first time in */
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LEN, /* i: waiting for length/lit/eob code */
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LENEXT, /* i: waiting for length extra bits */
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DIST, /* i: waiting for distance code */
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DISTEXT, /* i: waiting for distance extra bits */
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MATCH, /* o: waiting for output space to copy string */
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LIT, /* o: waiting for output space to write literal */
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CHECK, /* i: waiting for 32-bit check value */
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LENGTH, /* i: waiting for 32-bit length (gzip) */
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DONE, /* finished check, done -- remain here until reset */
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BAD, /* got a data error -- remain here until reset */
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MEM, /* got an inflate() memory error -- remain here until reset */
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SYNC /* looking for synchronization bytes to restart inflate() */
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} inflate_mode;
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/* State maintained between inflate() calls -- approximately 7K bytes, not
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including the allocated sliding window, which is up to 32K bytes. */
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struct inflate_state {
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z_streamp strm; /* pointer back to this zlib stream */
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inflate_mode mode; /* current inflate mode */
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int last; /* true if processing last block */
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int wrap; /* bit 0 true for zlib, bit 1 true for gzip,
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bit 2 true to validate check value */
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int havedict; /* true if dictionary provided */
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int flags; /* gzip header method and flags (0 if zlib) */
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unsigned dmax; /* zlib header max distance (INFLATE_STRICT) */
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unsigned long check; /* protected copy of check value */
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unsigned long total; /* protected copy of output count */
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gz_headerp head; /* where to save gzip header information */
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/* sliding window */
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unsigned wbits; /* log base 2 of requested window size */
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unsigned wsize; /* window size or zero if not using window */
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unsigned whave; /* valid bytes in the window */
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unsigned wnext; /* window write index */
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unsigned char FAR *window; /* allocated sliding window, if needed */
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/* bit accumulator */
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unsigned long hold; /* input bit accumulator */
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unsigned bits; /* number of bits in "in" */
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/* for string and stored block copying */
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unsigned length; /* literal or length of data to copy */
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unsigned offset; /* distance back to copy string from */
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/* for table and code decoding */
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unsigned extra; /* extra bits needed */
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/* fixed and dynamic code tables */
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code const FAR *lencode; /* starting table for length/literal codes */
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code const FAR *distcode; /* starting table for distance codes */
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unsigned lenbits; /* index bits for lencode */
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unsigned distbits; /* index bits for distcode */
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/* dynamic table building */
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unsigned ncode; /* number of code length code lengths */
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unsigned nlen; /* number of length code lengths */
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unsigned ndist; /* number of distance code lengths */
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unsigned have; /* number of code lengths in lens[] */
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code FAR *next; /* next available space in codes[] */
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unsigned short lens[320]; /* temporary storage for code lengths */
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unsigned short work[288]; /* work area for code table building */
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code codes[ENOUGH]; /* space for code tables */
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int sane; /* if false, allow invalid distance too far */
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int back; /* bits back of last unprocessed length/lit */
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unsigned was; /* initial length of match */
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};
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/*
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Decode literal, length, and distance codes and write out the resulting
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literal and match bytes until either not enough input or output is
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available, an end-of-block is encountered, or a data error is encountered.
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When large enough input and output buffers are supplied to inflate(), for
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example, a 16K input buffer and a 64K output buffer, more than 95% of the
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inflate execution time is spent in this routine.
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Entry assumptions:
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state->mode == LEN
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strm->avail_in >= 6
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strm->avail_out >= 258
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start >= strm->avail_out
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state->bits < 8
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On return, state->mode is one of:
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LEN -- ran out of enough output space or enough available input
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TYPE -- reached end of block code, inflate() to interpret next block
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BAD -- error in block data
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Notes:
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- The maximum input bits used by a length/distance pair is 15 bits for the
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length code, 5 bits for the length extra, 15 bits for the distance code,
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and 13 bits for the distance extra. This totals 48 bits, or six bytes.
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Therefore if strm->avail_in >= 6, then there is enough input to avoid
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checking for available input while decoding.
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- The maximum bytes that a single length/distance pair can output is 258
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bytes, which is the maximum length that can be coded. inflate_fast()
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requires strm->avail_out >= 258 for each loop to avoid checking for
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output space.
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*/
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static void inflate_fast( z_streamp strm, unsigned start )
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{
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struct inflate_state FAR *state;
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z_const unsigned char FAR *in; /* local strm->next_in */
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z_const unsigned char FAR *last; /* have enough input while in < last */
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unsigned char FAR *out; /* local strm->next_out */
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unsigned char FAR *beg; /* inflate()'s initial strm->next_out */
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unsigned char FAR *end; /* while out < end, enough space available */
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#ifdef INFLATE_STRICT
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unsigned dmax; /* maximum distance from zlib header */
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#endif
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unsigned wsize; /* window size or zero if not using window */
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unsigned whave; /* valid bytes in the window */
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unsigned wnext; /* window write index */
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unsigned char FAR *window; /* allocated sliding window, if wsize != 0 */
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unsigned long hold; /* local strm->hold */
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unsigned bits; /* local strm->bits */
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code const FAR *lcode; /* local strm->lencode */
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code const FAR *dcode; /* local strm->distcode */
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unsigned lmask; /* mask for first level of length codes */
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unsigned dmask; /* mask for first level of distance codes */
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code here; /* retrieved table entry */
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unsigned op; /* code bits, operation, extra bits, or */
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/* window position, window bytes to copy */
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unsigned len; /* match length, unused bytes */
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unsigned dist; /* match distance */
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unsigned char FAR *from; /* where to copy match from */
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/* copy state to local variables */
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state = (struct inflate_state FAR *)strm->state;
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in = strm->next_in;
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last = in + (strm->avail_in - 5);
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out = strm->next_out;
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beg = out - (start - strm->avail_out);
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end = out + (strm->avail_out - 257);
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#ifdef INFLATE_STRICT
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dmax = state->dmax;
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#endif
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wsize = state->wsize;
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whave = state->whave;
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wnext = state->wnext;
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window = state->window;
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hold = state->hold;
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bits = state->bits;
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lcode = state->lencode;
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dcode = state->distcode;
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lmask = (1U << state->lenbits) - 1;
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dmask = (1U << state->distbits) - 1;
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/* decode literals and length/distances until end-of-block or not enough
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input data or output space */
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do {
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if (bits < 15) {
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hold += (unsigned long)(*in++) << bits;
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bits += 8;
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hold += (unsigned long)(*in++) << bits;
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bits += 8;
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}
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here = lcode[hold & lmask];
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dolen:
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op = (unsigned)(here.bits);
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hold >>= op;
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bits -= op;
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op = (unsigned)(here.op);
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if (op == 0) { /* literal */
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Tracevv((stderr, here.val >= 0x20 && here.val < 0x7f ?
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"inflate: literal '%c'\n" :
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"inflate: literal 0x%02x\n", here.val));
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*out++ = (unsigned char)(here.val);
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}
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else if (op & 16) { /* length base */
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len = (unsigned)(here.val);
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op &= 15; /* number of extra bits */
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if (op) {
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if (bits < op) {
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hold += (unsigned long)(*in++) << bits;
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bits += 8;
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}
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len += (unsigned)hold & ((1U << op) - 1);
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hold >>= op;
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bits -= op;
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}
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Tracevv((stderr, "inflate: length %u\n", len));
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if (bits < 15) {
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hold += (unsigned long)(*in++) << bits;
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bits += 8;
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hold += (unsigned long)(*in++) << bits;
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bits += 8;
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}
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here = dcode[hold & dmask];
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dodist:
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op = (unsigned)(here.bits);
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hold >>= op;
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bits -= op;
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op = (unsigned)(here.op);
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if (op & 16) { /* distance base */
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dist = (unsigned)(here.val);
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op &= 15; /* number of extra bits */
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if (bits < op) {
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hold += (unsigned long)(*in++) << bits;
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bits += 8;
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if (bits < op) {
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hold += (unsigned long)(*in++) << bits;
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bits += 8;
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}
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}
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dist += (unsigned)hold & ((1U << op) - 1);
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#ifdef INFLATE_STRICT
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if (dist > dmax) {
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strm->msg = (char *)"invalid distance too far back";
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state->mode = BAD;
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break;
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}
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#endif
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hold >>= op;
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bits -= op;
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Tracevv((stderr, "inflate: distance %u\n", dist));
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op = (unsigned)(out - beg); /* max distance in output */
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if (dist > op) { /* see if copy from window */
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op = dist - op; /* distance back in window */
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if (op > whave) {
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if (state->sane) {
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strm->msg =
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(char *)"invalid distance too far back";
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state->mode = BAD;
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break;
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}
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#ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR
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if (len <= op - whave) {
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do {
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*out++ = 0;
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} while (--len);
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continue;
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}
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len -= op - whave;
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do {
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*out++ = 0;
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} while (--op > whave);
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if (op == 0) {
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from = out - dist;
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do {
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*out++ = *from++;
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} while (--len);
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continue;
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}
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#endif
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}
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from = window;
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if (wnext == 0) { /* very common case */
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from += wsize - op;
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if (op < len) { /* some from window */
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len -= op;
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do {
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*out++ = *from++;
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} while (--op);
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from = out - dist; /* rest from output */
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}
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}
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else if (wnext < op) { /* wrap around window */
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from += wsize + wnext - op;
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op -= wnext;
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if (op < len) { /* some from end of window */
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len -= op;
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do {
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*out++ = *from++;
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} while (--op);
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from = window;
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if (wnext < len) { /* some from start of window */
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op = wnext;
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len -= op;
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do {
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*out++ = *from++;
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} while (--op);
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from = out - dist; /* rest from output */
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}
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}
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}
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else { /* contiguous in window */
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from += wnext - op;
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if (op < len) { /* some from window */
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len -= op;
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do {
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*out++ = *from++;
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} while (--op);
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from = out - dist; /* rest from output */
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}
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}
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while (len > 2) {
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*out++ = *from++;
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*out++ = *from++;
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*out++ = *from++;
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len -= 3;
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}
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if (len) {
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*out++ = *from++;
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if (len > 1)
|
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*out++ = *from++;
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}
|
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}
|
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else {
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from = out - dist; /* copy direct from output */
|
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do { /* minimum length is three */
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*out++ = *from++;
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*out++ = *from++;
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*out++ = *from++;
|
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len -= 3;
|
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} while (len > 2);
|
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if (len) {
|
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*out++ = *from++;
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if (len > 1)
|
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*out++ = *from++;
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}
|
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}
|
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}
|
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else if ((op & 64) == 0) { /* 2nd level distance code */
|
|
here = dcode[here.val + (hold & ((1U << op) - 1))];
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goto dodist;
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|
}
|
|
else {
|
|
strm->msg = (char *)"invalid distance code";
|
|
state->mode = BAD;
|
|
break;
|
|
}
|
|
}
|
|
else if ((op & 64) == 0) { /* 2nd level length code */
|
|
here = lcode[here.val + (hold & ((1U << op) - 1))];
|
|
goto dolen;
|
|
}
|
|
else if (op & 32) { /* end-of-block */
|
|
Tracevv((stderr, "inflate: end of block\n"));
|
|
state->mode = TYPE;
|
|
break;
|
|
}
|
|
else {
|
|
strm->msg = (char *)"invalid literal/length code";
|
|
state->mode = BAD;
|
|
break;
|
|
}
|
|
} while (in < last && out < end);
|
|
|
|
/* return unused bytes (on entry, bits < 8, so in won't go too far back) */
|
|
len = bits >> 3;
|
|
in -= len;
|
|
bits -= len << 3;
|
|
hold &= (1U << bits) - 1;
|
|
|
|
/* update state and return */
|
|
strm->next_in = in;
|
|
strm->next_out = out;
|
|
strm->avail_in = (unsigned)(in < last ? 5 + (last - in) : 5 - (in - last));
|
|
strm->avail_out = (unsigned)(out < end ?
|
|
257 + (end - out) : 257 - (out - end));
|
|
state->hold = hold;
|
|
state->bits = bits;
|
|
return;
|
|
}
|
|
|
|
#define MAXBITS 15
|
|
|
|
static int inflate_table( codetype type, unsigned short FAR *lens, unsigned codes, code FAR * FAR *table,
|
|
unsigned FAR *bits, unsigned short FAR *work )
|
|
{
|
|
unsigned len; /* a code's length in bits */
|
|
unsigned sym; /* index of code symbols */
|
|
unsigned min, max; /* minimum and maximum code lengths */
|
|
unsigned root; /* number of index bits for root table */
|
|
unsigned curr; /* number of index bits for current table */
|
|
unsigned drop; /* code bits to drop for sub-table */
|
|
int left; /* number of prefix codes available */
|
|
unsigned used; /* code entries in table used */
|
|
unsigned huff; /* Huffman code */
|
|
unsigned incr; /* for incrementing code, index */
|
|
unsigned fill; /* index for replicating entries */
|
|
unsigned low; /* low bits for current root entry */
|
|
unsigned mask; /* mask for low root bits */
|
|
code here; /* table entry for duplication */
|
|
code FAR *next; /* next available space in table */
|
|
const unsigned short FAR *base; /* base value table to use */
|
|
const unsigned short FAR *extra; /* extra bits table to use */
|
|
unsigned match; /* use base and extra for symbol >= match */
|
|
unsigned short count[MAXBITS+1]; /* number of codes of each length */
|
|
unsigned short offs[MAXBITS+1]; /* offsets in table for each length */
|
|
static const unsigned short lbase[31] = { /* Length codes 257..285 base */
|
|
3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
|
|
35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
|
|
static const unsigned short lext[31] = { /* Length codes 257..285 extra */
|
|
16, 16, 16, 16, 16, 16, 16, 16, 17, 17, 17, 17, 18, 18, 18, 18,
|
|
19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 16, 77, 202};
|
|
static const unsigned short dbase[32] = { /* Distance codes 0..29 base */
|
|
1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
|
|
257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
|
|
8193, 12289, 16385, 24577, 0, 0};
|
|
static const unsigned short dext[32] = { /* Distance codes 0..29 extra */
|
|
16, 16, 16, 16, 17, 17, 18, 18, 19, 19, 20, 20, 21, 21, 22, 22,
|
|
23, 23, 24, 24, 25, 25, 26, 26, 27, 27,
|
|
28, 28, 29, 29, 64, 64};
|
|
|
|
/*
|
|
Process a set of code lengths to create a canonical Huffman code. The
|
|
code lengths are lens[0..codes-1]. Each length corresponds to the
|
|
symbols 0..codes-1. The Huffman code is generated by first sorting the
|
|
symbols by length from short to long, and retaining the symbol order
|
|
for codes with equal lengths. Then the code starts with all zero bits
|
|
for the first code of the shortest length, and the codes are integer
|
|
increments for the same length, and zeros are appended as the length
|
|
increases. For the deflate format, these bits are stored backwards
|
|
from their more natural integer increment ordering, and so when the
|
|
decoding tables are built in the large loop below, the integer codes
|
|
are incremented backwards.
|
|
|
|
This routine assumes, but does not check, that all of the entries in
|
|
lens[] are in the range 0..MAXBITS. The caller must assure this.
|
|
1..MAXBITS is interpreted as that code length. zero means that that
|
|
symbol does not occur in this code.
|
|
|
|
The codes are sorted by computing a count of codes for each length,
|
|
creating from that a table of starting indices for each length in the
|
|
sorted table, and then entering the symbols in order in the sorted
|
|
table. The sorted table is work[], with that space being provided by
|
|
the caller.
|
|
|
|
The length counts are used for other purposes as well, i.e. finding
|
|
the minimum and maximum length codes, determining if there are any
|
|
codes at all, checking for a valid set of lengths, and looking ahead
|
|
at length counts to determine sub-table sizes when building the
|
|
decoding tables.
|
|
*/
|
|
|
|
/* accumulate lengths for codes (assumes lens[] all in 0..MAXBITS) */
|
|
for (len = 0; len <= MAXBITS; len++)
|
|
count[len] = 0;
|
|
for (sym = 0; sym < codes; sym++)
|
|
count[lens[sym]]++;
|
|
|
|
/* bound code lengths, force root to be within code lengths */
|
|
root = *bits;
|
|
for (max = MAXBITS; max >= 1; max--)
|
|
if (count[max] != 0) break;
|
|
if (root > max) root = max;
|
|
if (max == 0) { /* no symbols to code at all */
|
|
here.op = (unsigned char)64; /* invalid code marker */
|
|
here.bits = (unsigned char)1;
|
|
here.val = (unsigned short)0;
|
|
*(*table)++ = here; /* make a table to force an error */
|
|
*(*table)++ = here;
|
|
*bits = 1;
|
|
return 0; /* no symbols, but wait for decoding to report error */
|
|
}
|
|
for (min = 1; min < max; min++)
|
|
if (count[min] != 0) break;
|
|
if (root < min) root = min;
|
|
|
|
/* check for an over-subscribed or incomplete set of lengths */
|
|
left = 1;
|
|
for (len = 1; len <= MAXBITS; len++) {
|
|
left <<= 1;
|
|
left -= count[len];
|
|
if (left < 0) return -1; /* over-subscribed */
|
|
}
|
|
if (left > 0 && (type == CODES || max != 1))
|
|
return -1; /* incomplete set */
|
|
|
|
/* generate offsets into symbol table for each length for sorting */
|
|
offs[1] = 0;
|
|
for (len = 1; len < MAXBITS; len++)
|
|
offs[len + 1] = offs[len] + count[len];
|
|
|
|
/* sort symbols by length, by symbol order within each length */
|
|
for (sym = 0; sym < codes; sym++)
|
|
if (lens[sym] != 0) work[offs[lens[sym]]++] = (unsigned short)sym;
|
|
|
|
/*
|
|
Create and fill in decoding tables. In this loop, the table being
|
|
filled is at next and has curr index bits. The code being used is huff
|
|
with length len. That code is converted to an index by dropping drop
|
|
bits off of the bottom. For codes where len is less than drop + curr,
|
|
those top drop + curr - len bits are incremented through all values to
|
|
fill the table with replicated entries.
|
|
|
|
root is the number of index bits for the root table. When len exceeds
|
|
root, sub-tables are created pointed to by the root entry with an index
|
|
of the low root bits of huff. This is saved in low to check for when a
|
|
new sub-table should be started. drop is zero when the root table is
|
|
being filled, and drop is root when sub-tables are being filled.
|
|
|
|
When a new sub-table is needed, it is necessary to look ahead in the
|
|
code lengths to determine what size sub-table is needed. The length
|
|
counts are used for this, and so count[] is decremented as codes are
|
|
entered in the tables.
|
|
|
|
used keeps track of how many table entries have been allocated from the
|
|
provided *table space. It is checked for LENS and DIST tables against
|
|
the constants ENOUGH_LENS and ENOUGH_DISTS to guard against changes in
|
|
the initial root table size constants. See the comments in inftrees.h
|
|
for more information.
|
|
|
|
sym increments through all symbols, and the loop terminates when
|
|
all codes of length max, i.e. all codes, have been processed. This
|
|
routine permits incomplete codes, so another loop after this one fills
|
|
in the rest of the decoding tables with invalid code markers.
|
|
*/
|
|
|
|
/* set up for code type */
|
|
switch (type) {
|
|
case CODES:
|
|
base = extra = work; /* dummy value--not used */
|
|
match = 20;
|
|
break;
|
|
case LENS:
|
|
base = lbase;
|
|
extra = lext;
|
|
match = 257;
|
|
break;
|
|
default: /* DISTS */
|
|
base = dbase;
|
|
extra = dext;
|
|
match = 0;
|
|
}
|
|
|
|
/* initialize state for loop */
|
|
huff = 0; /* starting code */
|
|
sym = 0; /* starting code symbol */
|
|
len = min; /* starting code length */
|
|
next = *table; /* current table to fill in */
|
|
curr = root; /* current table index bits */
|
|
drop = 0; /* current bits to drop from code for index */
|
|
low = (unsigned)(-1); /* trigger new sub-table when len > root */
|
|
used = 1U << root; /* use root table entries */
|
|
mask = used - 1; /* mask for comparing low */
|
|
|
|
/* check available table space */
|
|
if ((type == LENS && used > ENOUGH_LENS) ||
|
|
(type == DISTS && used > ENOUGH_DISTS))
|
|
return 1;
|
|
|
|
/* process all codes and make table entries */
|
|
for (;;) {
|
|
/* create table entry */
|
|
here.bits = (unsigned char)(len - drop);
|
|
if (work[sym] + 1U < match) {
|
|
here.op = (unsigned char)0;
|
|
here.val = work[sym];
|
|
}
|
|
else if (work[sym] >= match) {
|
|
here.op = (unsigned char)(extra[work[sym] - match]);
|
|
here.val = base[work[sym] - match];
|
|
}
|
|
else {
|
|
here.op = (unsigned char)(32 + 64); /* end of block */
|
|
here.val = 0;
|
|
}
|
|
|
|
/* replicate for those indices with low len bits equal to huff */
|
|
incr = 1U << (len - drop);
|
|
fill = 1U << curr;
|
|
min = fill; /* save offset to next table */
|
|
do {
|
|
fill -= incr;
|
|
next[(huff >> drop) + fill] = here;
|
|
} while (fill != 0);
|
|
|
|
/* backwards increment the len-bit code huff */
|
|
incr = 1U << (len - 1);
|
|
while (huff & incr)
|
|
incr >>= 1;
|
|
if (incr != 0) {
|
|
huff &= incr - 1;
|
|
huff += incr;
|
|
}
|
|
else
|
|
huff = 0;
|
|
|
|
/* go to next symbol, update count, len */
|
|
sym++;
|
|
if (--(count[len]) == 0) {
|
|
if (len == max) break;
|
|
len = lens[work[sym]];
|
|
}
|
|
|
|
/* create new sub-table if needed */
|
|
if (len > root && (huff & mask) != low) {
|
|
/* if first time, transition to sub-tables */
|
|
if (drop == 0)
|
|
drop = root;
|
|
|
|
/* increment past last table */
|
|
next += min; /* here min is 1 << curr */
|
|
|
|
/* determine length of next table */
|
|
curr = len - drop;
|
|
left = (int)(1 << curr);
|
|
while (curr + drop < max) {
|
|
left -= count[curr + drop];
|
|
if (left <= 0) break;
|
|
curr++;
|
|
left <<= 1;
|
|
}
|
|
|
|
/* check for enough space */
|
|
used += 1U << curr;
|
|
if ((type == LENS && used > ENOUGH_LENS) ||
|
|
(type == DISTS && used > ENOUGH_DISTS))
|
|
return 1;
|
|
|
|
/* point entry in root table to sub-table */
|
|
low = huff & mask;
|
|
(*table)[low].op = (unsigned char)curr;
|
|
(*table)[low].bits = (unsigned char)root;
|
|
(*table)[low].val = (unsigned short)(next - *table);
|
|
}
|
|
}
|
|
|
|
/* fill in remaining table entry if code is incomplete (guaranteed to have
|
|
at most one remaining entry, since if the code is incomplete, the
|
|
maximum code length that was allowed to get this far is one bit) */
|
|
if (huff != 0) {
|
|
here.op = (unsigned char)64; /* invalid code marker */
|
|
here.bits = (unsigned char)(len - drop);
|
|
here.val = (unsigned short)0;
|
|
next[huff] = here;
|
|
}
|
|
|
|
/* set return parameters */
|
|
*table += used;
|
|
*bits = root;
|
|
return 0;
|
|
}
|
|
|
|
static int inflateStateCheck( z_streamp strm )
|
|
{
|
|
struct inflate_state FAR *state;
|
|
if (strm == Z_NULL ||
|
|
strm->zalloc == (alloc_func)0 || strm->zfree == (free_func)0)
|
|
return 1;
|
|
state = (struct inflate_state FAR *)strm->state;
|
|
if (state == Z_NULL || state->strm != strm ||
|
|
state->mode < HEAD || state->mode > SYNC)
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
static int inflateResetKeep( z_streamp strm )
|
|
{
|
|
struct inflate_state FAR *state;
|
|
|
|
if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
|
|
state = (struct inflate_state FAR *)strm->state;
|
|
strm->total_in = strm->total_out = state->total = 0;
|
|
strm->msg = Z_NULL;
|
|
if (state->wrap) /* to support ill-conceived Java test suite */
|
|
strm->adler = state->wrap & 1;
|
|
state->mode = HEAD;
|
|
state->last = 0;
|
|
state->havedict = 0;
|
|
state->dmax = 32768U;
|
|
state->head = Z_NULL;
|
|
state->hold = 0;
|
|
state->bits = 0;
|
|
state->lencode = state->distcode = state->next = state->codes;
|
|
state->sane = 1;
|
|
state->back = -1;
|
|
Tracev((stderr, "inflate: reset\n"));
|
|
return Z_OK;
|
|
}
|
|
|
|
static int inflateReset( z_streamp strm )
|
|
{
|
|
struct inflate_state FAR *state;
|
|
|
|
if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
|
|
state = (struct inflate_state FAR *)strm->state;
|
|
state->wsize = 0;
|
|
state->whave = 0;
|
|
state->wnext = 0;
|
|
return inflateResetKeep(strm);
|
|
}
|
|
|
|
static int inflateReset2( z_streamp strm, int windowBits )
|
|
{
|
|
int wrap;
|
|
struct inflate_state FAR *state;
|
|
|
|
/* get the state */
|
|
if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
|
|
state = (struct inflate_state FAR *)strm->state;
|
|
|
|
/* extract wrap request from windowBits parameter */
|
|
if (windowBits < 0) {
|
|
wrap = 0;
|
|
windowBits = -windowBits;
|
|
}
|
|
else {
|
|
wrap = (windowBits >> 4) + 5;
|
|
#ifdef GUNZIP
|
|
if (windowBits < 48)
|
|
windowBits &= 15;
|
|
#endif
|
|
}
|
|
|
|
/* set number of window bits, free window if different */
|
|
if (windowBits && (windowBits < 8 || windowBits > 15))
|
|
return Z_STREAM_ERROR;
|
|
if (state->window != Z_NULL && state->wbits != (unsigned)windowBits) {
|
|
ZFREE(strm, state->window);
|
|
state->window = Z_NULL;
|
|
}
|
|
|
|
/* update state and reset the rest of it */
|
|
state->wrap = wrap;
|
|
state->wbits = (unsigned)windowBits;
|
|
return inflateReset(strm);
|
|
}
|
|
|
|
int inflateInit2( z_streamp strm, int windowBits )
|
|
{
|
|
int ret;
|
|
struct inflate_state FAR *state;
|
|
|
|
strm->msg = Z_NULL; /* in case we return an error */
|
|
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;
|
|
state->strm = strm;
|
|
state->window = Z_NULL;
|
|
state->mode = HEAD; /* to pass state test in inflateReset2() */
|
|
ret = inflateReset2(strm, windowBits);
|
|
if (ret != Z_OK) {
|
|
ZFREE(strm, state);
|
|
strm->state = Z_NULL;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
int inflateInit( z_streamp strm )
|
|
{
|
|
return inflateInit2(strm, DEF_WBITS);
|
|
}
|
|
|
|
/*
|
|
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.
|
|
*/
|
|
static void fixedtables( struct inflate_state FAR *state )
|
|
{
|
|
static const code lenfix[512] = {
|
|
{96,7,0},{0,8,80},{0,8,16},{20,8,115},{18,7,31},{0,8,112},{0,8,48},
|
|
{0,9,192},{16,7,10},{0,8,96},{0,8,32},{0,9,160},{0,8,0},{0,8,128},
|
|
{0,8,64},{0,9,224},{16,7,6},{0,8,88},{0,8,24},{0,9,144},{19,7,59},
|
|
{0,8,120},{0,8,56},{0,9,208},{17,7,17},{0,8,104},{0,8,40},{0,9,176},
|
|
{0,8,8},{0,8,136},{0,8,72},{0,9,240},{16,7,4},{0,8,84},{0,8,20},
|
|
{21,8,227},{19,7,43},{0,8,116},{0,8,52},{0,9,200},{17,7,13},{0,8,100},
|
|
{0,8,36},{0,9,168},{0,8,4},{0,8,132},{0,8,68},{0,9,232},{16,7,8},
|
|
{0,8,92},{0,8,28},{0,9,152},{20,7,83},{0,8,124},{0,8,60},{0,9,216},
|
|
{18,7,23},{0,8,108},{0,8,44},{0,9,184},{0,8,12},{0,8,140},{0,8,76},
|
|
{0,9,248},{16,7,3},{0,8,82},{0,8,18},{21,8,163},{19,7,35},{0,8,114},
|
|
{0,8,50},{0,9,196},{17,7,11},{0,8,98},{0,8,34},{0,9,164},{0,8,2},
|
|
{0,8,130},{0,8,66},{0,9,228},{16,7,7},{0,8,90},{0,8,26},{0,9,148},
|
|
{20,7,67},{0,8,122},{0,8,58},{0,9,212},{18,7,19},{0,8,106},{0,8,42},
|
|
{0,9,180},{0,8,10},{0,8,138},{0,8,74},{0,9,244},{16,7,5},{0,8,86},
|
|
{0,8,22},{64,8,0},{19,7,51},{0,8,118},{0,8,54},{0,9,204},{17,7,15},
|
|
{0,8,102},{0,8,38},{0,9,172},{0,8,6},{0,8,134},{0,8,70},{0,9,236},
|
|
{16,7,9},{0,8,94},{0,8,30},{0,9,156},{20,7,99},{0,8,126},{0,8,62},
|
|
{0,9,220},{18,7,27},{0,8,110},{0,8,46},{0,9,188},{0,8,14},{0,8,142},
|
|
{0,8,78},{0,9,252},{96,7,0},{0,8,81},{0,8,17},{21,8,131},{18,7,31},
|
|
{0,8,113},{0,8,49},{0,9,194},{16,7,10},{0,8,97},{0,8,33},{0,9,162},
|
|
{0,8,1},{0,8,129},{0,8,65},{0,9,226},{16,7,6},{0,8,89},{0,8,25},
|
|
{0,9,146},{19,7,59},{0,8,121},{0,8,57},{0,9,210},{17,7,17},{0,8,105},
|
|
{0,8,41},{0,9,178},{0,8,9},{0,8,137},{0,8,73},{0,9,242},{16,7,4},
|
|
{0,8,85},{0,8,21},{16,8,258},{19,7,43},{0,8,117},{0,8,53},{0,9,202},
|
|
{17,7,13},{0,8,101},{0,8,37},{0,9,170},{0,8,5},{0,8,133},{0,8,69},
|
|
{0,9,234},{16,7,8},{0,8,93},{0,8,29},{0,9,154},{20,7,83},{0,8,125},
|
|
{0,8,61},{0,9,218},{18,7,23},{0,8,109},{0,8,45},{0,9,186},{0,8,13},
|
|
{0,8,141},{0,8,77},{0,9,250},{16,7,3},{0,8,83},{0,8,19},{21,8,195},
|
|
{19,7,35},{0,8,115},{0,8,51},{0,9,198},{17,7,11},{0,8,99},{0,8,35},
|
|
{0,9,166},{0,8,3},{0,8,131},{0,8,67},{0,9,230},{16,7,7},{0,8,91},
|
|
{0,8,27},{0,9,150},{20,7,67},{0,8,123},{0,8,59},{0,9,214},{18,7,19},
|
|
{0,8,107},{0,8,43},{0,9,182},{0,8,11},{0,8,139},{0,8,75},{0,9,246},
|
|
{16,7,5},{0,8,87},{0,8,23},{64,8,0},{19,7,51},{0,8,119},{0,8,55},
|
|
{0,9,206},{17,7,15},{0,8,103},{0,8,39},{0,9,174},{0,8,7},{0,8,135},
|
|
{0,8,71},{0,9,238},{16,7,9},{0,8,95},{0,8,31},{0,9,158},{20,7,99},
|
|
{0,8,127},{0,8,63},{0,9,222},{18,7,27},{0,8,111},{0,8,47},{0,9,190},
|
|
{0,8,15},{0,8,143},{0,8,79},{0,9,254},{96,7,0},{0,8,80},{0,8,16},
|
|
{20,8,115},{18,7,31},{0,8,112},{0,8,48},{0,9,193},{16,7,10},{0,8,96},
|
|
{0,8,32},{0,9,161},{0,8,0},{0,8,128},{0,8,64},{0,9,225},{16,7,6},
|
|
{0,8,88},{0,8,24},{0,9,145},{19,7,59},{0,8,120},{0,8,56},{0,9,209},
|
|
{17,7,17},{0,8,104},{0,8,40},{0,9,177},{0,8,8},{0,8,136},{0,8,72},
|
|
{0,9,241},{16,7,4},{0,8,84},{0,8,20},{21,8,227},{19,7,43},{0,8,116},
|
|
{0,8,52},{0,9,201},{17,7,13},{0,8,100},{0,8,36},{0,9,169},{0,8,4},
|
|
{0,8,132},{0,8,68},{0,9,233},{16,7,8},{0,8,92},{0,8,28},{0,9,153},
|
|
{20,7,83},{0,8,124},{0,8,60},{0,9,217},{18,7,23},{0,8,108},{0,8,44},
|
|
{0,9,185},{0,8,12},{0,8,140},{0,8,76},{0,9,249},{16,7,3},{0,8,82},
|
|
{0,8,18},{21,8,163},{19,7,35},{0,8,114},{0,8,50},{0,9,197},{17,7,11},
|
|
{0,8,98},{0,8,34},{0,9,165},{0,8,2},{0,8,130},{0,8,66},{0,9,229},
|
|
{16,7,7},{0,8,90},{0,8,26},{0,9,149},{20,7,67},{0,8,122},{0,8,58},
|
|
{0,9,213},{18,7,19},{0,8,106},{0,8,42},{0,9,181},{0,8,10},{0,8,138},
|
|
{0,8,74},{0,9,245},{16,7,5},{0,8,86},{0,8,22},{64,8,0},{19,7,51},
|
|
{0,8,118},{0,8,54},{0,9,205},{17,7,15},{0,8,102},{0,8,38},{0,9,173},
|
|
{0,8,6},{0,8,134},{0,8,70},{0,9,237},{16,7,9},{0,8,94},{0,8,30},
|
|
{0,9,157},{20,7,99},{0,8,126},{0,8,62},{0,9,221},{18,7,27},{0,8,110},
|
|
{0,8,46},{0,9,189},{0,8,14},{0,8,142},{0,8,78},{0,9,253},{96,7,0},
|
|
{0,8,81},{0,8,17},{21,8,131},{18,7,31},{0,8,113},{0,8,49},{0,9,195},
|
|
{16,7,10},{0,8,97},{0,8,33},{0,9,163},{0,8,1},{0,8,129},{0,8,65},
|
|
{0,9,227},{16,7,6},{0,8,89},{0,8,25},{0,9,147},{19,7,59},{0,8,121},
|
|
{0,8,57},{0,9,211},{17,7,17},{0,8,105},{0,8,41},{0,9,179},{0,8,9},
|
|
{0,8,137},{0,8,73},{0,9,243},{16,7,4},{0,8,85},{0,8,21},{16,8,258},
|
|
{19,7,43},{0,8,117},{0,8,53},{0,9,203},{17,7,13},{0,8,101},{0,8,37},
|
|
{0,9,171},{0,8,5},{0,8,133},{0,8,69},{0,9,235},{16,7,8},{0,8,93},
|
|
{0,8,29},{0,9,155},{20,7,83},{0,8,125},{0,8,61},{0,9,219},{18,7,23},
|
|
{0,8,109},{0,8,45},{0,9,187},{0,8,13},{0,8,141},{0,8,77},{0,9,251},
|
|
{16,7,3},{0,8,83},{0,8,19},{21,8,195},{19,7,35},{0,8,115},{0,8,51},
|
|
{0,9,199},{17,7,11},{0,8,99},{0,8,35},{0,9,167},{0,8,3},{0,8,131},
|
|
{0,8,67},{0,9,231},{16,7,7},{0,8,91},{0,8,27},{0,9,151},{20,7,67},
|
|
{0,8,123},{0,8,59},{0,9,215},{18,7,19},{0,8,107},{0,8,43},{0,9,183},
|
|
{0,8,11},{0,8,139},{0,8,75},{0,9,247},{16,7,5},{0,8,87},{0,8,23},
|
|
{64,8,0},{19,7,51},{0,8,119},{0,8,55},{0,9,207},{17,7,15},{0,8,103},
|
|
{0,8,39},{0,9,175},{0,8,7},{0,8,135},{0,8,71},{0,9,239},{16,7,9},
|
|
{0,8,95},{0,8,31},{0,9,159},{20,7,99},{0,8,127},{0,8,63},{0,9,223},
|
|
{18,7,27},{0,8,111},{0,8,47},{0,9,191},{0,8,15},{0,8,143},{0,8,79},
|
|
{0,9,255}
|
|
};
|
|
|
|
static const code distfix[32] = {
|
|
{16,5,1},{23,5,257},{19,5,17},{27,5,4097},{17,5,5},{25,5,1025},
|
|
{21,5,65},{29,5,16385},{16,5,3},{24,5,513},{20,5,33},{28,5,8193},
|
|
{18,5,9},{26,5,2049},{22,5,129},{64,5,0},{16,5,2},{23,5,385},
|
|
{19,5,25},{27,5,6145},{17,5,7},{25,5,1537},{21,5,97},{29,5,24577},
|
|
{16,5,4},{24,5,769},{20,5,49},{28,5,12289},{18,5,13},{26,5,3073},
|
|
{22,5,193},{64,5,0}
|
|
};
|
|
|
|
state->lencode = lenfix;
|
|
state->lenbits = 9;
|
|
state->distcode = distfix;
|
|
state->distbits = 5;
|
|
}
|
|
|
|
/*
|
|
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.
|
|
*/
|
|
static int updatewindow( z_streamp strm, const Bytef *end, unsigned copy )
|
|
{
|
|
struct inflate_state FAR *state;
|
|
unsigned 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->wnext = 0;
|
|
state->whave = 0;
|
|
}
|
|
|
|
/* copy state->wsize or less output bytes into the circular window */
|
|
if (copy >= state->wsize) {
|
|
zmemcpy(state->window, end - state->wsize, state->wsize);
|
|
state->wnext = 0;
|
|
state->whave = state->wsize;
|
|
}
|
|
else {
|
|
dist = state->wsize - state->wnext;
|
|
if (dist > copy) dist = copy;
|
|
zmemcpy(state->window + state->wnext, end - copy, dist);
|
|
copy -= dist;
|
|
if (copy) {
|
|
zmemcpy(state->window, end - copy, copy);
|
|
state->wnext = copy;
|
|
state->whave = state->wsize;
|
|
}
|
|
else {
|
|
state->wnext += dist;
|
|
if (state->wnext == state->wsize) state->wnext = 0;
|
|
if (state->whave < state->wsize) state->whave += dist;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/* Macros for inflate(): */
|
|
|
|
#define crc32(crc,buf,len) RtlComputeCrc32(crc,buf,len)
|
|
|
|
/* 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)
|
|
|
|
/*
|
|
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 inflate( z_streamp strm, int flush )
|
|
{
|
|
struct inflate_state FAR *state;
|
|
z_const 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 here; /* 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 (inflateStateCheck(strm) || 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 */
|
|
if (state->wbits == 0)
|
|
state->wbits = 15;
|
|
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 (state->wbits == 0)
|
|
state->wbits = len;
|
|
if (len > 15 || 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) && (state->wrap & 4))
|
|
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) && (state->wrap & 4))
|
|
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) && (state->wrap & 4))
|
|
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) && (state->wrap & 4))
|
|
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->wrap & 4))
|
|
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++] = (Bytef)len;
|
|
} while (len && copy < have);
|
|
if ((state->flags & 0x0200) && (state->wrap & 4))
|
|
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++] = (Bytef)len;
|
|
} while (len && copy < have);
|
|
if ((state->flags & 0x0200) && (state->wrap & 4))
|
|
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 ((state->wrap & 4) && 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 = ZSWAP32(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 || flush == Z_TREES) 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 */
|
|
if (flush == Z_TREES) {
|
|
DROPBITS(2);
|
|
goto inf_leave;
|
|
}
|
|
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_;
|
|
if (flush == Z_TREES) goto inf_leave;
|
|
case COPY_:
|
|
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 = (const code 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 (;;) {
|
|
here = state->lencode[BITS(state->lenbits)];
|
|
if ((unsigned)(here.bits) <= bits) break;
|
|
PULLBYTE();
|
|
}
|
|
if (here.val < 16) {
|
|
DROPBITS(here.bits);
|
|
state->lens[state->have++] = here.val;
|
|
}
|
|
else {
|
|
if (here.val == 16) {
|
|
NEEDBITS(here.bits + 2);
|
|
DROPBITS(here.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 (here.val == 17) {
|
|
NEEDBITS(here.bits + 3);
|
|
DROPBITS(here.bits);
|
|
len = 0;
|
|
copy = 3 + BITS(3);
|
|
DROPBITS(3);
|
|
}
|
|
else {
|
|
NEEDBITS(here.bits + 7);
|
|
DROPBITS(here.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;
|
|
|
|
/* check for end-of-block code (better have one) */
|
|
if (state->lens[256] == 0) {
|
|
strm->msg = (char *)"invalid code -- missing end-of-block";
|
|
state->mode = BAD;
|
|
break;
|
|
}
|
|
|
|
/* build code tables -- note: do not change the lenbits or distbits
|
|
values here (9 and 6) without reading the comments in inftrees.h
|
|
concerning the ENOUGH constants, which depend on those values */
|
|
state->next = state->codes;
|
|
state->lencode = (const code 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 = (const code 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_;
|
|
if (flush == Z_TREES) goto inf_leave;
|
|
case LEN_:
|
|
state->mode = LEN;
|
|
case LEN:
|
|
if (have >= 6 && left >= 258) {
|
|
RESTORE();
|
|
inflate_fast(strm, out);
|
|
LOAD();
|
|
if (state->mode == TYPE)
|
|
state->back = -1;
|
|
break;
|
|
}
|
|
state->back = 0;
|
|
for (;;) {
|
|
here = state->lencode[BITS(state->lenbits)];
|
|
if ((unsigned)(here.bits) <= bits) break;
|
|
PULLBYTE();
|
|
}
|
|
if (here.op && (here.op & 0xf0) == 0) {
|
|
last = here;
|
|
for (;;) {
|
|
here = state->lencode[last.val +
|
|
(BITS(last.bits + last.op) >> last.bits)];
|
|
if ((unsigned)(last.bits + here.bits) <= bits) break;
|
|
PULLBYTE();
|
|
}
|
|
DROPBITS(last.bits);
|
|
state->back += last.bits;
|
|
}
|
|
DROPBITS(here.bits);
|
|
state->back += here.bits;
|
|
state->length = (unsigned)here.val;
|
|
if ((int)(here.op) == 0) {
|
|
Tracevv((stderr, here.val >= 0x20 && here.val < 0x7f ?
|
|
"inflate: literal '%c'\n" :
|
|
"inflate: literal 0x%02x\n", here.val));
|
|
state->mode = LIT;
|
|
break;
|
|
}
|
|
if (here.op & 32) {
|
|
Tracevv((stderr, "inflate: end of block\n"));
|
|
state->back = -1;
|
|
state->mode = TYPE;
|
|
break;
|
|
}
|
|
if (here.op & 64) {
|
|
strm->msg = (char *)"invalid literal/length code";
|
|
state->mode = BAD;
|
|
break;
|
|
}
|
|
state->extra = (unsigned)(here.op) & 15;
|
|
state->mode = LENEXT;
|
|
case LENEXT:
|
|
if (state->extra) {
|
|
NEEDBITS(state->extra);
|
|
state->length += BITS(state->extra);
|
|
DROPBITS(state->extra);
|
|
state->back += state->extra;
|
|
}
|
|
Tracevv((stderr, "inflate: length %u\n", state->length));
|
|
state->was = state->length;
|
|
state->mode = DIST;
|
|
case DIST:
|
|
for (;;) {
|
|
here = state->distcode[BITS(state->distbits)];
|
|
if ((unsigned)(here.bits) <= bits) break;
|
|
PULLBYTE();
|
|
}
|
|
if ((here.op & 0xf0) == 0) {
|
|
last = here;
|
|
for (;;) {
|
|
here = state->distcode[last.val +
|
|
(BITS(last.bits + last.op) >> last.bits)];
|
|
if ((unsigned)(last.bits + here.bits) <= bits) break;
|
|
PULLBYTE();
|
|
}
|
|
DROPBITS(last.bits);
|
|
state->back += last.bits;
|
|
}
|
|
DROPBITS(here.bits);
|
|
state->back += here.bits;
|
|
if (here.op & 64) {
|
|
strm->msg = (char *)"invalid distance code";
|
|
state->mode = BAD;
|
|
break;
|
|
}
|
|
state->offset = (unsigned)here.val;
|
|
state->extra = (unsigned)(here.op) & 15;
|
|
state->mode = DISTEXT;
|
|
case DISTEXT:
|
|
if (state->extra) {
|
|
NEEDBITS(state->extra);
|
|
state->offset += BITS(state->extra);
|
|
DROPBITS(state->extra);
|
|
state->back += state->extra;
|
|
}
|
|
#ifdef INFLATE_STRICT
|
|
if (state->offset > state->dmax) {
|
|
strm->msg = (char *)"invalid distance too far back";
|
|
state->mode = BAD;
|
|
break;
|
|
}
|
|
#endif
|
|
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->whave) {
|
|
if (state->sane) {
|
|
strm->msg = (char *)"invalid distance too far back";
|
|
state->mode = BAD;
|
|
break;
|
|
}
|
|
#ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR
|
|
Trace((stderr, "inflate.c too far\n"));
|
|
copy -= state->whave;
|
|
if (copy > state->length) copy = state->length;
|
|
if (copy > left) copy = left;
|
|
left -= copy;
|
|
state->length -= copy;
|
|
do {
|
|
*put++ = 0;
|
|
} while (--copy);
|
|
if (state->length == 0) state->mode = LEN;
|
|
break;
|
|
#endif
|
|
}
|
|
if (copy > state->wnext) {
|
|
copy -= state->wnext;
|
|
from = state->window + (state->wsize - copy);
|
|
}
|
|
else
|
|
from = state->window + (state->wnext - 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 ((state->wrap & 4) && out)
|
|
strm->adler = state->check =
|
|
UPDATE(state->check, put - out, out);
|
|
out = left;
|
|
if ((state->wrap & 4) && (
|
|
#ifdef GUNZIP
|
|
state->flags ? hold :
|
|
#endif
|
|
ZSWAP32(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 || (out != strm->avail_out && state->mode < BAD &&
|
|
(state->mode < CHECK || flush != Z_FINISH)))
|
|
if (updatewindow(strm, strm->next_out, out - strm->avail_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 & 4) && out)
|
|
strm->adler = state->check =
|
|
UPDATE(state->check, strm->next_out - out, out);
|
|
strm->data_type = (int)state->bits + (state->last ? 64 : 0) +
|
|
(state->mode == TYPE ? 128 : 0) +
|
|
(state->mode == LEN_ || state->mode == COPY_ ? 256 : 0);
|
|
if (((in == 0 && out == 0) || flush == Z_FINISH) && ret == Z_OK)
|
|
ret = Z_BUF_ERROR;
|
|
return ret;
|
|
}
|
|
|
|
int inflateEnd(z_streamp strm)
|
|
{
|
|
struct inflate_state FAR *state;
|
|
if (inflateStateCheck(strm))
|
|
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;
|
|
}
|