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2194 lines
66 KiB
2194 lines
66 KiB
/*
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* This file is derived from various .h and .c files from the zlib-0.95
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* distribution by Jean-loup Gailly and Mark Adler, with some additions
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* by Paul Mackerras to aid in implementing Deflate compression and
|
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* decompression for PPP packets. See zlib.h for conditions of
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* distribution and use.
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*
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* Changes that have been made include:
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* - changed functions not used outside this file to "local"
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* - added minCompression parameter to deflateInit2
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* - added Z_PACKET_FLUSH (see zlib.h for details)
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* - added inflateIncomp
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*
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Copyright (C) 1995 Jean-loup Gailly and Mark Adler
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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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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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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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Jean-loup Gailly Mark Adler
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gzip@prep.ai.mit.edu madler@alumni.caltech.edu
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*
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*
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*/
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/*+++++*/
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/* zutil.h -- internal interface and configuration of the compression library
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* Copyright (C) 1995 Jean-loup Gailly.
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* For conditions of distribution and use, see copyright notice in zlib.h
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*/
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/* WARNING: this file should *not* be used by applications. It is
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part of the implementation of the compression library and is
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subject to change. Applications should only use zlib.h.
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*/
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/* From: zutil.h,v 1.9 1995/05/03 17:27:12 jloup Exp */
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#define _Z_UTIL_H
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#include "zlib.h"
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#ifndef local
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# define local static
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#endif
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/* compile with -Dlocal if your debugger can't find static symbols */
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#define FAR
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typedef unsigned char uch;
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typedef uch FAR uchf;
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typedef unsigned short ush;
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typedef ush FAR ushf;
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typedef unsigned long ulg;
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extern char *z_errmsg[]; /* indexed by 1-zlib_error */
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#define ERR_RETURN(strm,err) return (strm->msg=z_errmsg[1-err], err)
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/* To be used only when the state is known to be valid */
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#ifndef NULL
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#define NULL ((void *) 0)
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#endif
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/* common constants */
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#define DEFLATED 8
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#ifndef DEF_WBITS
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# define DEF_WBITS MAX_WBITS
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#endif
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/* default windowBits for decompression. MAX_WBITS is for compression only */
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#if MAX_MEM_LEVEL >= 8
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# define DEF_MEM_LEVEL 8
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#else
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# define DEF_MEM_LEVEL MAX_MEM_LEVEL
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#endif
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/* default memLevel */
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#define STORED_BLOCK 0
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#define STATIC_TREES 1
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#define DYN_TREES 2
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/* The three kinds of block type */
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#define MIN_MATCH 3
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#define MAX_MATCH 258
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/* The minimum and maximum match lengths */
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|
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/* functions */
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extern void *memcpy(void *, const void *, unsigned long);
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#define zmemcpy memcpy
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|
|
/* Diagnostic functions */
|
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#ifdef DEBUG_ZLIB
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# include <stdio.h>
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# ifndef verbose
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# define verbose 0
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# endif
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# define Assert(cond,msg) {if(!(cond)) z_error(msg);}
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# define Trace(x) fprintf x
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# define Tracev(x) {if (verbose) fprintf x ;}
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# define Tracevv(x) {if (verbose>1) fprintf x ;}
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# define Tracec(c,x) {if (verbose && (c)) fprintf x ;}
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# define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;}
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#else
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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 Tracec(c,x)
|
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# define Tracecv(c,x)
|
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#endif
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|
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typedef uLong (*check_func) OF((uLong check, Bytef *buf, uInt len));
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/* voidpf zcalloc OF((voidpf opaque, unsigned items, unsigned size)); */
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/* void zcfree OF((voidpf opaque, voidpf ptr)); */
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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, size) \
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(*((strm)->zfree))((strm)->opaque, (voidpf)(addr), (size))
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#define TRY_FREE(s, p, n) {if (p) ZFREE(s, p, n);}
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|
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/* deflate.h -- internal compression state
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* Copyright (C) 1995 Jean-loup Gailly
|
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* For conditions of distribution and use, see copyright notice in zlib.h
|
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*/
|
|
|
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/* WARNING: this file should *not* be used by applications. It is
|
|
part of the implementation of the compression library and is
|
|
subject to change. Applications should only use zlib.h.
|
|
*/
|
|
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/*+++++*/
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/* infblock.h -- header to use infblock.c
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* Copyright (C) 1995 Mark Adler
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* For conditions of distribution and use, see copyright notice in zlib.h
|
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*/
|
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|
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/* WARNING: this file should *not* be used by applications. It is
|
|
part of the implementation of the compression library and is
|
|
subject to change. Applications should only use zlib.h.
|
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*/
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struct inflate_blocks_state;
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typedef struct inflate_blocks_state FAR inflate_blocks_statef;
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local inflate_blocks_statef * inflate_blocks_new OF((
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z_stream *z,
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check_func c, /* check function */
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uInt w)); /* window size */
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local int inflate_blocks OF((
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inflate_blocks_statef *,
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z_stream *,
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int)); /* initial return code */
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local void inflate_blocks_reset OF((
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inflate_blocks_statef *,
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z_stream *,
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uLongf *)); /* check value on output */
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local int inflate_blocks_free OF((
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inflate_blocks_statef *,
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z_stream *,
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uLongf *)); /* check value on output */
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local int inflate_addhistory OF((
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inflate_blocks_statef *,
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z_stream *));
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local int inflate_packet_flush OF((
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inflate_blocks_statef *));
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/*+++++*/
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/* inftrees.h -- header to use inftrees.c
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* Copyright (C) 1995 Mark Adler
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* For conditions of distribution and use, see copyright notice in zlib.h
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*/
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|
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/* WARNING: this file should *not* be used by applications. It is
|
|
part of the implementation of the compression library and is
|
|
subject to change. Applications should only use zlib.h.
|
|
*/
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/* Huffman code lookup table entry--this entry is four bytes for machines
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that have 16-bit pointers (e.g. PC's in the small or medium model). */
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typedef struct inflate_huft_s FAR inflate_huft;
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struct inflate_huft_s {
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union {
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struct {
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|
Byte Exop; /* number of extra bits or operation */
|
|
Byte Bits; /* number of bits in this code or subcode */
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|
} what;
|
|
uInt Nalloc; /* number of these allocated here */
|
|
Bytef *pad; /* pad structure to a power of 2 (4 bytes for */
|
|
} word; /* 16-bit, 8 bytes for 32-bit machines) */
|
|
union {
|
|
uInt Base; /* literal, length base, or distance base */
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|
inflate_huft *Next; /* pointer to next level of table */
|
|
} more;
|
|
};
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#ifdef DEBUG_ZLIB
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local uInt inflate_hufts;
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|
#endif
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|
local int inflate_trees_bits OF((
|
|
uIntf *, /* 19 code lengths */
|
|
uIntf *, /* bits tree desired/actual depth */
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|
inflate_huft * FAR *, /* bits tree result */
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|
z_stream *)); /* for zalloc, zfree functions */
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local int inflate_trees_dynamic OF((
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uInt, /* number of literal/length codes */
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|
uInt, /* number of distance codes */
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uIntf *, /* that many (total) code lengths */
|
|
uIntf *, /* literal desired/actual bit depth */
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|
uIntf *, /* distance desired/actual bit depth */
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|
inflate_huft * FAR *, /* literal/length tree result */
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|
inflate_huft * FAR *, /* distance tree result */
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|
z_stream *)); /* for zalloc, zfree functions */
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local int inflate_trees_fixed OF((
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uIntf *, /* literal desired/actual bit depth */
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uIntf *, /* distance desired/actual bit depth */
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inflate_huft * FAR *, /* literal/length tree result */
|
|
inflate_huft * FAR *)); /* distance tree result */
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|
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local int inflate_trees_free OF((
|
|
inflate_huft *, /* tables to free */
|
|
z_stream *)); /* for zfree function */
|
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|
|
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/*+++++*/
|
|
/* infcodes.h -- header to use infcodes.c
|
|
* Copyright (C) 1995 Mark Adler
|
|
* For conditions of distribution and use, see copyright notice in zlib.h
|
|
*/
|
|
|
|
/* WARNING: this file should *not* be used by applications. It is
|
|
part of the implementation of the compression library and is
|
|
subject to change. Applications should only use zlib.h.
|
|
*/
|
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|
|
struct inflate_codes_state;
|
|
typedef struct inflate_codes_state FAR inflate_codes_statef;
|
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|
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local inflate_codes_statef *inflate_codes_new OF((
|
|
uInt, uInt,
|
|
inflate_huft *, inflate_huft *,
|
|
z_stream *));
|
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|
|
local int inflate_codes OF((
|
|
inflate_blocks_statef *,
|
|
z_stream *,
|
|
int));
|
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|
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local void inflate_codes_free OF((
|
|
inflate_codes_statef *,
|
|
z_stream *));
|
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|
|
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/*+++++*/
|
|
/* inflate.c -- zlib interface to inflate modules
|
|
* Copyright (C) 1995 Mark Adler
|
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* For conditions of distribution and use, see copyright notice in zlib.h
|
|
*/
|
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|
|
/* inflate private state */
|
|
struct internal_state {
|
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|
|
/* mode */
|
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enum {
|
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METHOD, /* waiting for method byte */
|
|
FLAG, /* waiting for flag byte */
|
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BLOCKS, /* decompressing blocks */
|
|
CHECK4, /* four check bytes to go */
|
|
CHECK3, /* three check bytes to go */
|
|
CHECK2, /* two check bytes to go */
|
|
CHECK1, /* one check byte to go */
|
|
DONE, /* finished check, done */
|
|
BAD} /* got an error--stay here */
|
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mode; /* current inflate mode */
|
|
|
|
/* mode dependent information */
|
|
union {
|
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uInt method; /* if FLAGS, method byte */
|
|
struct {
|
|
uLong was; /* computed check value */
|
|
uLong need; /* stream check value */
|
|
} check; /* if CHECK, check values to compare */
|
|
uInt marker; /* if BAD, inflateSync's marker bytes count */
|
|
} sub; /* submode */
|
|
|
|
/* mode independent information */
|
|
int nowrap; /* flag for no wrapper */
|
|
uInt wbits; /* log2(window size) (8..15, defaults to 15) */
|
|
inflate_blocks_statef
|
|
*blocks; /* current inflate_blocks state */
|
|
|
|
};
|
|
|
|
|
|
int inflateReset(
|
|
z_stream *z
|
|
)
|
|
{
|
|
uLong c;
|
|
|
|
if (z == Z_NULL || z->state == Z_NULL)
|
|
return Z_STREAM_ERROR;
|
|
z->total_in = z->total_out = 0;
|
|
z->msg = Z_NULL;
|
|
z->state->mode = z->state->nowrap ? BLOCKS : METHOD;
|
|
inflate_blocks_reset(z->state->blocks, z, &c);
|
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Trace((stderr, "inflate: reset\n"));
|
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return Z_OK;
|
|
}
|
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|
|
|
|
int inflateEnd(
|
|
z_stream *z
|
|
)
|
|
{
|
|
uLong c;
|
|
|
|
if (z == Z_NULL || z->state == Z_NULL || z->zfree == Z_NULL)
|
|
return Z_STREAM_ERROR;
|
|
if (z->state->blocks != Z_NULL)
|
|
inflate_blocks_free(z->state->blocks, z, &c);
|
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ZFREE(z, z->state, sizeof(struct internal_state));
|
|
z->state = Z_NULL;
|
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Trace((stderr, "inflate: end\n"));
|
|
return Z_OK;
|
|
}
|
|
|
|
|
|
int inflateInit2(
|
|
z_stream *z,
|
|
int w
|
|
)
|
|
{
|
|
/* initialize state */
|
|
if (z == Z_NULL)
|
|
return Z_STREAM_ERROR;
|
|
/* if (z->zalloc == Z_NULL) z->zalloc = zcalloc; */
|
|
/* if (z->zfree == Z_NULL) z->zfree = zcfree; */
|
|
if ((z->state = (struct internal_state FAR *)
|
|
ZALLOC(z,1,sizeof(struct internal_state))) == Z_NULL)
|
|
return Z_MEM_ERROR;
|
|
z->state->blocks = Z_NULL;
|
|
|
|
/* handle undocumented nowrap option (no zlib header or check) */
|
|
z->state->nowrap = 0;
|
|
if (w < 0)
|
|
{
|
|
w = - w;
|
|
z->state->nowrap = 1;
|
|
}
|
|
|
|
/* set window size */
|
|
if (w < 8 || w > 15)
|
|
{
|
|
inflateEnd(z);
|
|
return Z_STREAM_ERROR;
|
|
}
|
|
z->state->wbits = (uInt)w;
|
|
|
|
/* create inflate_blocks state */
|
|
if ((z->state->blocks =
|
|
inflate_blocks_new(z, z->state->nowrap ? Z_NULL : adler32, 1 << w))
|
|
== Z_NULL)
|
|
{
|
|
inflateEnd(z);
|
|
return Z_MEM_ERROR;
|
|
}
|
|
Trace((stderr, "inflate: allocated\n"));
|
|
|
|
/* reset state */
|
|
inflateReset(z);
|
|
return Z_OK;
|
|
}
|
|
|
|
|
|
int inflateInit(
|
|
z_stream *z
|
|
)
|
|
{
|
|
return inflateInit2(z, DEF_WBITS);
|
|
}
|
|
|
|
|
|
#define NEEDBYTE {if(z->avail_in==0)goto empty;r=Z_OK;}
|
|
#define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++)
|
|
|
|
int inflate(
|
|
z_stream *z,
|
|
int f
|
|
)
|
|
{
|
|
int r;
|
|
uInt b;
|
|
|
|
if (z == Z_NULL || z->next_in == Z_NULL)
|
|
return Z_STREAM_ERROR;
|
|
r = Z_BUF_ERROR;
|
|
while (1) switch (z->state->mode)
|
|
{
|
|
case METHOD:
|
|
NEEDBYTE
|
|
if (((z->state->sub.method = NEXTBYTE) & 0xf) != DEFLATED)
|
|
{
|
|
z->state->mode = BAD;
|
|
z->msg = "unknown compression method";
|
|
z->state->sub.marker = 5; /* can't try inflateSync */
|
|
break;
|
|
}
|
|
if ((z->state->sub.method >> 4) + 8 > z->state->wbits)
|
|
{
|
|
z->state->mode = BAD;
|
|
z->msg = "invalid window size";
|
|
z->state->sub.marker = 5; /* can't try inflateSync */
|
|
break;
|
|
}
|
|
z->state->mode = FLAG;
|
|
case FLAG:
|
|
NEEDBYTE
|
|
if ((b = NEXTBYTE) & 0x20)
|
|
{
|
|
z->state->mode = BAD;
|
|
z->msg = "invalid reserved bit";
|
|
z->state->sub.marker = 5; /* can't try inflateSync */
|
|
break;
|
|
}
|
|
if (((z->state->sub.method << 8) + b) % 31)
|
|
{
|
|
z->state->mode = BAD;
|
|
z->msg = "incorrect header check";
|
|
z->state->sub.marker = 5; /* can't try inflateSync */
|
|
break;
|
|
}
|
|
Trace((stderr, "inflate: zlib header ok\n"));
|
|
z->state->mode = BLOCKS;
|
|
case BLOCKS:
|
|
r = inflate_blocks(z->state->blocks, z, r);
|
|
if (f == Z_PACKET_FLUSH && z->avail_in == 0 && z->avail_out != 0)
|
|
r = inflate_packet_flush(z->state->blocks);
|
|
if (r == Z_DATA_ERROR)
|
|
{
|
|
z->state->mode = BAD;
|
|
z->state->sub.marker = 0; /* can try inflateSync */
|
|
break;
|
|
}
|
|
if (r != Z_STREAM_END)
|
|
return r;
|
|
r = Z_OK;
|
|
inflate_blocks_reset(z->state->blocks, z, &z->state->sub.check.was);
|
|
if (z->state->nowrap)
|
|
{
|
|
z->state->mode = DONE;
|
|
break;
|
|
}
|
|
z->state->mode = CHECK4;
|
|
case CHECK4:
|
|
NEEDBYTE
|
|
z->state->sub.check.need = (uLong)NEXTBYTE << 24;
|
|
z->state->mode = CHECK3;
|
|
case CHECK3:
|
|
NEEDBYTE
|
|
z->state->sub.check.need += (uLong)NEXTBYTE << 16;
|
|
z->state->mode = CHECK2;
|
|
case CHECK2:
|
|
NEEDBYTE
|
|
z->state->sub.check.need += (uLong)NEXTBYTE << 8;
|
|
z->state->mode = CHECK1;
|
|
case CHECK1:
|
|
NEEDBYTE
|
|
z->state->sub.check.need += (uLong)NEXTBYTE;
|
|
|
|
if (z->state->sub.check.was != z->state->sub.check.need)
|
|
{
|
|
z->state->mode = BAD;
|
|
z->msg = "incorrect data check";
|
|
z->state->sub.marker = 5; /* can't try inflateSync */
|
|
break;
|
|
}
|
|
Trace((stderr, "inflate: zlib check ok\n"));
|
|
z->state->mode = DONE;
|
|
case DONE:
|
|
return Z_STREAM_END;
|
|
case BAD:
|
|
return Z_DATA_ERROR;
|
|
default:
|
|
return Z_STREAM_ERROR;
|
|
}
|
|
|
|
empty:
|
|
if (f != Z_PACKET_FLUSH)
|
|
return r;
|
|
z->state->mode = BAD;
|
|
z->state->sub.marker = 0; /* can try inflateSync */
|
|
return Z_DATA_ERROR;
|
|
}
|
|
|
|
/*
|
|
* This subroutine adds the data at next_in/avail_in to the output history
|
|
* without performing any output. The output buffer must be "caught up";
|
|
* i.e. no pending output (hence s->read equals s->write), and the state must
|
|
* be BLOCKS (i.e. we should be willing to see the start of a series of
|
|
* BLOCKS). On exit, the output will also be caught up, and the checksum
|
|
* will have been updated if need be.
|
|
*/
|
|
|
|
int inflateIncomp(
|
|
z_stream *z
|
|
)
|
|
{
|
|
if (z->state->mode != BLOCKS)
|
|
return Z_DATA_ERROR;
|
|
return inflate_addhistory(z->state->blocks, z);
|
|
}
|
|
|
|
|
|
int inflateSync(
|
|
z_stream *z
|
|
)
|
|
{
|
|
uInt n; /* number of bytes to look at */
|
|
Bytef *p; /* pointer to bytes */
|
|
uInt m; /* number of marker bytes found in a row */
|
|
uLong r, w; /* temporaries to save total_in and total_out */
|
|
|
|
/* set up */
|
|
if (z == Z_NULL || z->state == Z_NULL)
|
|
return Z_STREAM_ERROR;
|
|
if (z->state->mode != BAD)
|
|
{
|
|
z->state->mode = BAD;
|
|
z->state->sub.marker = 0;
|
|
}
|
|
if ((n = z->avail_in) == 0)
|
|
return Z_BUF_ERROR;
|
|
p = z->next_in;
|
|
m = z->state->sub.marker;
|
|
|
|
/* search */
|
|
while (n && m < 4)
|
|
{
|
|
if (*p == (Byte)(m < 2 ? 0 : 0xff))
|
|
m++;
|
|
else if (*p)
|
|
m = 0;
|
|
else
|
|
m = 4 - m;
|
|
p++, n--;
|
|
}
|
|
|
|
/* restore */
|
|
z->total_in += p - z->next_in;
|
|
z->next_in = p;
|
|
z->avail_in = n;
|
|
z->state->sub.marker = m;
|
|
|
|
/* return no joy or set up to restart on a new block */
|
|
if (m != 4)
|
|
return Z_DATA_ERROR;
|
|
r = z->total_in; w = z->total_out;
|
|
inflateReset(z);
|
|
z->total_in = r; z->total_out = w;
|
|
z->state->mode = BLOCKS;
|
|
return Z_OK;
|
|
}
|
|
|
|
#undef NEEDBYTE
|
|
#undef NEXTBYTE
|
|
|
|
/*+++++*/
|
|
/* infutil.h -- types and macros common to blocks and codes
|
|
* Copyright (C) 1995 Mark Adler
|
|
* For conditions of distribution and use, see copyright notice in zlib.h
|
|
*/
|
|
|
|
/* WARNING: this file should *not* be used by applications. It is
|
|
part of the implementation of the compression library and is
|
|
subject to change. Applications should only use zlib.h.
|
|
*/
|
|
|
|
/* inflate blocks semi-private state */
|
|
struct inflate_blocks_state {
|
|
|
|
/* mode */
|
|
enum {
|
|
TYPE, /* get type bits (3, including end bit) */
|
|
LENS, /* get lengths for stored */
|
|
STORED, /* processing stored block */
|
|
TABLE, /* get table lengths */
|
|
BTREE, /* get bit lengths tree for a dynamic block */
|
|
DTREE, /* get length, distance trees for a dynamic block */
|
|
CODES, /* processing fixed or dynamic block */
|
|
DRY, /* output remaining window bytes */
|
|
DONEB, /* finished last block, done */
|
|
BADB} /* got a data error--stuck here */
|
|
mode; /* current inflate_block mode */
|
|
|
|
/* mode dependent information */
|
|
union {
|
|
uInt left; /* if STORED, bytes left to copy */
|
|
struct {
|
|
uInt table; /* table lengths (14 bits) */
|
|
uInt index; /* index into blens (or border) */
|
|
uIntf *blens; /* bit lengths of codes */
|
|
uInt bb; /* bit length tree depth */
|
|
inflate_huft *tb; /* bit length decoding tree */
|
|
int nblens; /* # elements allocated at blens */
|
|
} trees; /* if DTREE, decoding info for trees */
|
|
struct {
|
|
inflate_huft *tl, *td; /* trees to free */
|
|
inflate_codes_statef
|
|
*codes;
|
|
} decode; /* if CODES, current state */
|
|
} sub; /* submode */
|
|
uInt last; /* true if this block is the last block */
|
|
|
|
/* mode independent information */
|
|
uInt bitk; /* bits in bit buffer */
|
|
uLong bitb; /* bit buffer */
|
|
Bytef *window; /* sliding window */
|
|
Bytef *end; /* one byte after sliding window */
|
|
Bytef *read; /* window read pointer */
|
|
Bytef *write; /* window write pointer */
|
|
check_func checkfn; /* check function */
|
|
uLong check; /* check on output */
|
|
|
|
};
|
|
|
|
|
|
/* defines for inflate input/output */
|
|
/* update pointers and return */
|
|
#define UPDBITS {s->bitb=b;s->bitk=k;}
|
|
#define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;}
|
|
#define UPDOUT {s->write=q;}
|
|
#define UPDATE {UPDBITS UPDIN UPDOUT}
|
|
#define LEAVE {UPDATE return inflate_flush(s,z,r);}
|
|
/* get bytes and bits */
|
|
#define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;}
|
|
#define NEEDBYTE {if(n)r=Z_OK;else LEAVE}
|
|
#define NEXTBYTE (n--,*p++)
|
|
#define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}}
|
|
#define DUMPBITS(j) {b>>=(j);k-=(j);}
|
|
/* output bytes */
|
|
#define WAVAIL (q<s->read?s->read-q-1:s->end-q)
|
|
#define LOADOUT {q=s->write;m=WAVAIL;}
|
|
#define WRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=WAVAIL;}}
|
|
#define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT}
|
|
#define NEEDOUT {if(m==0){WRAP if(m==0){FLUSH WRAP if(m==0) LEAVE}}r=Z_OK;}
|
|
#define OUTBYTE(a) {*q++=(Byte)(a);m--;}
|
|
/* load local pointers */
|
|
#define LOAD {LOADIN LOADOUT}
|
|
|
|
/* And'ing with mask[n] masks the lower n bits */
|
|
local uInt inflate_mask[] = {
|
|
0x0000,
|
|
0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
|
|
0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
|
|
};
|
|
|
|
/* copy as much as possible from the sliding window to the output area */
|
|
local int inflate_flush OF((
|
|
inflate_blocks_statef *,
|
|
z_stream *,
|
|
int));
|
|
|
|
/*+++++*/
|
|
/* inffast.h -- header to use inffast.c
|
|
* Copyright (C) 1995 Mark Adler
|
|
* For conditions of distribution and use, see copyright notice in zlib.h
|
|
*/
|
|
|
|
/* WARNING: this file should *not* be used by applications. It is
|
|
part of the implementation of the compression library and is
|
|
subject to change. Applications should only use zlib.h.
|
|
*/
|
|
|
|
local int inflate_fast OF((
|
|
uInt,
|
|
uInt,
|
|
inflate_huft *,
|
|
inflate_huft *,
|
|
inflate_blocks_statef *,
|
|
z_stream *));
|
|
|
|
|
|
/*+++++*/
|
|
/* infblock.c -- interpret and process block types to last block
|
|
* Copyright (C) 1995 Mark Adler
|
|
* For conditions of distribution and use, see copyright notice in zlib.h
|
|
*/
|
|
|
|
/* Table for deflate from PKZIP's appnote.txt. */
|
|
local uInt border[] = { /* Order of the bit length code lengths */
|
|
16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
|
|
|
|
/*
|
|
Notes beyond the 1.93a appnote.txt:
|
|
|
|
1. Distance pointers never point before the beginning of the output
|
|
stream.
|
|
2. Distance pointers can point back across blocks, up to 32k away.
|
|
3. There is an implied maximum of 7 bits for the bit length table and
|
|
15 bits for the actual data.
|
|
4. If only one code exists, then it is encoded using one bit. (Zero
|
|
would be more efficient, but perhaps a little confusing.) If two
|
|
codes exist, they are coded using one bit each (0 and 1).
|
|
5. There is no way of sending zero distance codes--a dummy must be
|
|
sent if there are none. (History: a pre 2.0 version of PKZIP would
|
|
store blocks with no distance codes, but this was discovered to be
|
|
too harsh a criterion.) Valid only for 1.93a. 2.04c does allow
|
|
zero distance codes, which is sent as one code of zero bits in
|
|
length.
|
|
6. There are up to 286 literal/length codes. Code 256 represents the
|
|
end-of-block. Note however that the static length tree defines
|
|
288 codes just to fill out the Huffman codes. Codes 286 and 287
|
|
cannot be used though, since there is no length base or extra bits
|
|
defined for them. Similarily, there are up to 30 distance codes.
|
|
However, static trees define 32 codes (all 5 bits) to fill out the
|
|
Huffman codes, but the last two had better not show up in the data.
|
|
7. Unzip can check dynamic Huffman blocks for complete code sets.
|
|
The exception is that a single code would not be complete (see #4).
|
|
8. The five bits following the block type is really the number of
|
|
literal codes sent minus 257.
|
|
9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits
|
|
(1+6+6). Therefore, to output three times the length, you output
|
|
three codes (1+1+1), whereas to output four times the same length,
|
|
you only need two codes (1+3). Hmm.
|
|
10. In the tree reconstruction algorithm, Code = Code + Increment
|
|
only if BitLength(i) is not zero. (Pretty obvious.)
|
|
11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19)
|
|
12. Note: length code 284 can represent 227-258, but length code 285
|
|
really is 258. The last length deserves its own, short code
|
|
since it gets used a lot in very redundant files. The length
|
|
258 is special since 258 - 3 (the min match length) is 255.
|
|
13. The literal/length and distance code bit lengths are read as a
|
|
single stream of lengths. It is possible (and advantageous) for
|
|
a repeat code (16, 17, or 18) to go across the boundary between
|
|
the two sets of lengths.
|
|
*/
|
|
|
|
|
|
local void inflate_blocks_reset(
|
|
inflate_blocks_statef *s,
|
|
z_stream *z,
|
|
uLongf *c
|
|
)
|
|
{
|
|
if (s->checkfn != Z_NULL)
|
|
*c = s->check;
|
|
if (s->mode == BTREE || s->mode == DTREE)
|
|
ZFREE(z, s->sub.trees.blens, s->sub.trees.nblens * sizeof(uInt));
|
|
if (s->mode == CODES)
|
|
{
|
|
inflate_codes_free(s->sub.decode.codes, z);
|
|
inflate_trees_free(s->sub.decode.td, z);
|
|
inflate_trees_free(s->sub.decode.tl, z);
|
|
}
|
|
s->mode = TYPE;
|
|
s->bitk = 0;
|
|
s->bitb = 0;
|
|
s->read = s->write = s->window;
|
|
if (s->checkfn != Z_NULL)
|
|
s->check = (*s->checkfn)(0L, Z_NULL, 0);
|
|
Trace((stderr, "inflate: blocks reset\n"));
|
|
}
|
|
|
|
|
|
local inflate_blocks_statef *inflate_blocks_new(
|
|
z_stream *z,
|
|
check_func c,
|
|
uInt w
|
|
)
|
|
{
|
|
inflate_blocks_statef *s;
|
|
|
|
if ((s = (inflate_blocks_statef *)ZALLOC
|
|
(z,1,sizeof(struct inflate_blocks_state))) == Z_NULL)
|
|
return s;
|
|
if ((s->window = (Bytef *)ZALLOC(z, 1, w)) == Z_NULL)
|
|
{
|
|
ZFREE(z, s, sizeof(struct inflate_blocks_state));
|
|
return Z_NULL;
|
|
}
|
|
s->end = s->window + w;
|
|
s->checkfn = c;
|
|
s->mode = TYPE;
|
|
Trace((stderr, "inflate: blocks allocated\n"));
|
|
inflate_blocks_reset(s, z, &s->check);
|
|
return s;
|
|
}
|
|
|
|
|
|
local int inflate_blocks(
|
|
inflate_blocks_statef *s,
|
|
z_stream *z,
|
|
int r
|
|
)
|
|
{
|
|
uInt t; /* temporary storage */
|
|
uLong b; /* bit buffer */
|
|
uInt k; /* bits in bit buffer */
|
|
Bytef *p; /* input data pointer */
|
|
uInt n; /* bytes available there */
|
|
Bytef *q; /* output window write pointer */
|
|
uInt m; /* bytes to end of window or read pointer */
|
|
|
|
/* copy input/output information to locals (UPDATE macro restores) */
|
|
LOAD
|
|
|
|
/* process input based on current state */
|
|
while (1) switch (s->mode)
|
|
{
|
|
case TYPE:
|
|
NEEDBITS(3)
|
|
t = (uInt)b & 7;
|
|
s->last = t & 1;
|
|
switch (t >> 1)
|
|
{
|
|
case 0: /* stored */
|
|
Trace((stderr, "inflate: stored block%s\n",
|
|
s->last ? " (last)" : ""));
|
|
DUMPBITS(3)
|
|
t = k & 7; /* go to byte boundary */
|
|
DUMPBITS(t)
|
|
s->mode = LENS; /* get length of stored block */
|
|
break;
|
|
case 1: /* fixed */
|
|
Trace((stderr, "inflate: fixed codes block%s\n",
|
|
s->last ? " (last)" : ""));
|
|
{
|
|
uInt bl, bd;
|
|
inflate_huft *tl, *td;
|
|
|
|
inflate_trees_fixed(&bl, &bd, &tl, &td);
|
|
s->sub.decode.codes = inflate_codes_new(bl, bd, tl, td, z);
|
|
if (s->sub.decode.codes == Z_NULL)
|
|
{
|
|
r = Z_MEM_ERROR;
|
|
LEAVE
|
|
}
|
|
s->sub.decode.tl = Z_NULL; /* don't try to free these */
|
|
s->sub.decode.td = Z_NULL;
|
|
}
|
|
DUMPBITS(3)
|
|
s->mode = CODES;
|
|
break;
|
|
case 2: /* dynamic */
|
|
Trace((stderr, "inflate: dynamic codes block%s\n",
|
|
s->last ? " (last)" : ""));
|
|
DUMPBITS(3)
|
|
s->mode = TABLE;
|
|
break;
|
|
case 3: /* illegal */
|
|
DUMPBITS(3)
|
|
s->mode = BADB;
|
|
z->msg = "invalid block type";
|
|
r = Z_DATA_ERROR;
|
|
LEAVE
|
|
}
|
|
break;
|
|
case LENS:
|
|
NEEDBITS(32)
|
|
if (((~b) >> 16) != (b & 0xffff))
|
|
{
|
|
s->mode = BADB;
|
|
z->msg = "invalid stored block lengths";
|
|
r = Z_DATA_ERROR;
|
|
LEAVE
|
|
}
|
|
s->sub.left = (uInt)b & 0xffff;
|
|
b = k = 0; /* dump bits */
|
|
Tracev((stderr, "inflate: stored length %u\n", s->sub.left));
|
|
s->mode = s->sub.left ? STORED : TYPE;
|
|
break;
|
|
case STORED:
|
|
if (n == 0)
|
|
LEAVE
|
|
NEEDOUT
|
|
t = s->sub.left;
|
|
if (t > n) t = n;
|
|
if (t > m) t = m;
|
|
zmemcpy(q, p, t);
|
|
p += t; n -= t;
|
|
q += t; m -= t;
|
|
if ((s->sub.left -= t) != 0)
|
|
break;
|
|
Tracev((stderr, "inflate: stored end, %lu total out\n",
|
|
z->total_out + (q >= s->read ? q - s->read :
|
|
(s->end - s->read) + (q - s->window))));
|
|
s->mode = s->last ? DRY : TYPE;
|
|
break;
|
|
case TABLE:
|
|
NEEDBITS(14)
|
|
s->sub.trees.table = t = (uInt)b & 0x3fff;
|
|
#ifndef PKZIP_BUG_WORKAROUND
|
|
if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29)
|
|
{
|
|
s->mode = BADB;
|
|
z->msg = "too many length or distance symbols";
|
|
r = Z_DATA_ERROR;
|
|
LEAVE
|
|
}
|
|
#endif
|
|
t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f);
|
|
if (t < 19)
|
|
t = 19;
|
|
if ((s->sub.trees.blens = (uIntf*)ZALLOC(z, t, sizeof(uInt))) == Z_NULL)
|
|
{
|
|
r = Z_MEM_ERROR;
|
|
LEAVE
|
|
}
|
|
s->sub.trees.nblens = t;
|
|
DUMPBITS(14)
|
|
s->sub.trees.index = 0;
|
|
Tracev((stderr, "inflate: table sizes ok\n"));
|
|
s->mode = BTREE;
|
|
case BTREE:
|
|
while (s->sub.trees.index < 4 + (s->sub.trees.table >> 10))
|
|
{
|
|
NEEDBITS(3)
|
|
s->sub.trees.blens[border[s->sub.trees.index++]] = (uInt)b & 7;
|
|
DUMPBITS(3)
|
|
}
|
|
while (s->sub.trees.index < 19)
|
|
s->sub.trees.blens[border[s->sub.trees.index++]] = 0;
|
|
s->sub.trees.bb = 7;
|
|
t = inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb,
|
|
&s->sub.trees.tb, z);
|
|
if (t != Z_OK)
|
|
{
|
|
r = t;
|
|
if (r == Z_DATA_ERROR)
|
|
s->mode = BADB;
|
|
LEAVE
|
|
}
|
|
s->sub.trees.index = 0;
|
|
Tracev((stderr, "inflate: bits tree ok\n"));
|
|
s->mode = DTREE;
|
|
case DTREE:
|
|
while (t = s->sub.trees.table,
|
|
s->sub.trees.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f))
|
|
{
|
|
inflate_huft *h;
|
|
uInt i, j, c;
|
|
|
|
t = s->sub.trees.bb;
|
|
NEEDBITS(t)
|
|
h = s->sub.trees.tb + ((uInt)b & inflate_mask[t]);
|
|
t = h->word.what.Bits;
|
|
c = h->more.Base;
|
|
if (c < 16)
|
|
{
|
|
DUMPBITS(t)
|
|
s->sub.trees.blens[s->sub.trees.index++] = c;
|
|
}
|
|
else /* c == 16..18 */
|
|
{
|
|
i = c == 18 ? 7 : c - 14;
|
|
j = c == 18 ? 11 : 3;
|
|
NEEDBITS(t + i)
|
|
DUMPBITS(t)
|
|
j += (uInt)b & inflate_mask[i];
|
|
DUMPBITS(i)
|
|
i = s->sub.trees.index;
|
|
t = s->sub.trees.table;
|
|
if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) ||
|
|
(c == 16 && i < 1))
|
|
{
|
|
s->mode = BADB;
|
|
z->msg = "invalid bit length repeat";
|
|
r = Z_DATA_ERROR;
|
|
LEAVE
|
|
}
|
|
c = c == 16 ? s->sub.trees.blens[i - 1] : 0;
|
|
do {
|
|
s->sub.trees.blens[i++] = c;
|
|
} while (--j);
|
|
s->sub.trees.index = i;
|
|
}
|
|
}
|
|
inflate_trees_free(s->sub.trees.tb, z);
|
|
s->sub.trees.tb = Z_NULL;
|
|
{
|
|
uInt bl, bd;
|
|
inflate_huft *tl, *td;
|
|
inflate_codes_statef *c;
|
|
|
|
bl = 9; /* must be <= 9 for lookahead assumptions */
|
|
bd = 6; /* must be <= 9 for lookahead assumptions */
|
|
t = s->sub.trees.table;
|
|
t = inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f),
|
|
s->sub.trees.blens, &bl, &bd, &tl, &td, z);
|
|
if (t != Z_OK)
|
|
{
|
|
if (t == (uInt)Z_DATA_ERROR)
|
|
s->mode = BADB;
|
|
r = t;
|
|
LEAVE
|
|
}
|
|
Tracev((stderr, "inflate: trees ok\n"));
|
|
if ((c = inflate_codes_new(bl, bd, tl, td, z)) == Z_NULL)
|
|
{
|
|
inflate_trees_free(td, z);
|
|
inflate_trees_free(tl, z);
|
|
r = Z_MEM_ERROR;
|
|
LEAVE
|
|
}
|
|
ZFREE(z, s->sub.trees.blens, s->sub.trees.nblens * sizeof(uInt));
|
|
s->sub.decode.codes = c;
|
|
s->sub.decode.tl = tl;
|
|
s->sub.decode.td = td;
|
|
}
|
|
s->mode = CODES;
|
|
case CODES:
|
|
UPDATE
|
|
if ((r = inflate_codes(s, z, r)) != Z_STREAM_END)
|
|
return inflate_flush(s, z, r);
|
|
r = Z_OK;
|
|
inflate_codes_free(s->sub.decode.codes, z);
|
|
inflate_trees_free(s->sub.decode.td, z);
|
|
inflate_trees_free(s->sub.decode.tl, z);
|
|
LOAD
|
|
Tracev((stderr, "inflate: codes end, %lu total out\n",
|
|
z->total_out + (q >= s->read ? q - s->read :
|
|
(s->end - s->read) + (q - s->window))));
|
|
if (!s->last)
|
|
{
|
|
s->mode = TYPE;
|
|
break;
|
|
}
|
|
if (k > 7) /* return unused byte, if any */
|
|
{
|
|
Assert(k < 16, "inflate_codes grabbed too many bytes")
|
|
k -= 8;
|
|
n++;
|
|
p--; /* can always return one */
|
|
}
|
|
s->mode = DRY;
|
|
case DRY:
|
|
FLUSH
|
|
if (s->read != s->write)
|
|
LEAVE
|
|
s->mode = DONEB;
|
|
case DONEB:
|
|
r = Z_STREAM_END;
|
|
LEAVE
|
|
case BADB:
|
|
r = Z_DATA_ERROR;
|
|
LEAVE
|
|
default:
|
|
r = Z_STREAM_ERROR;
|
|
LEAVE
|
|
}
|
|
}
|
|
|
|
|
|
local int inflate_blocks_free(
|
|
inflate_blocks_statef *s,
|
|
z_stream *z,
|
|
uLongf *c
|
|
)
|
|
{
|
|
inflate_blocks_reset(s, z, c);
|
|
ZFREE(z, s->window, s->end - s->window);
|
|
ZFREE(z, s, sizeof(struct inflate_blocks_state));
|
|
Trace((stderr, "inflate: blocks freed\n"));
|
|
return Z_OK;
|
|
}
|
|
|
|
/*
|
|
* This subroutine adds the data at next_in/avail_in to the output history
|
|
* without performing any output. The output buffer must be "caught up";
|
|
* i.e. no pending output (hence s->read equals s->write), and the state must
|
|
* be BLOCKS (i.e. we should be willing to see the start of a series of
|
|
* BLOCKS). On exit, the output will also be caught up, and the checksum
|
|
* will have been updated if need be.
|
|
*/
|
|
local int inflate_addhistory(
|
|
inflate_blocks_statef *s,
|
|
z_stream *z
|
|
)
|
|
{
|
|
uLong b; /* bit buffer */ /* NOT USED HERE */
|
|
uInt k; /* bits in bit buffer */ /* NOT USED HERE */
|
|
uInt t; /* temporary storage */
|
|
Bytef *p; /* input data pointer */
|
|
uInt n; /* bytes available there */
|
|
Bytef *q; /* output window write pointer */
|
|
uInt m; /* bytes to end of window or read pointer */
|
|
|
|
if (s->read != s->write)
|
|
return Z_STREAM_ERROR;
|
|
if (s->mode != TYPE)
|
|
return Z_DATA_ERROR;
|
|
|
|
/* we're ready to rock */
|
|
LOAD
|
|
/* while there is input ready, copy to output buffer, moving
|
|
* pointers as needed.
|
|
*/
|
|
while (n) {
|
|
t = n; /* how many to do */
|
|
/* is there room until end of buffer? */
|
|
if (t > m) t = m;
|
|
/* update check information */
|
|
if (s->checkfn != Z_NULL)
|
|
s->check = (*s->checkfn)(s->check, q, t);
|
|
zmemcpy(q, p, t);
|
|
q += t;
|
|
p += t;
|
|
n -= t;
|
|
z->total_out += t;
|
|
s->read = q; /* drag read pointer forward */
|
|
/* WRAP */ /* expand WRAP macro by hand to handle s->read */
|
|
if (q == s->end) {
|
|
s->read = q = s->window;
|
|
m = WAVAIL;
|
|
}
|
|
}
|
|
UPDATE
|
|
return Z_OK;
|
|
}
|
|
|
|
|
|
/*
|
|
* At the end of a Deflate-compressed PPP packet, we expect to have seen
|
|
* a `stored' block type value but not the (zero) length bytes.
|
|
*/
|
|
local int inflate_packet_flush(
|
|
inflate_blocks_statef *s
|
|
)
|
|
{
|
|
if (s->mode != LENS)
|
|
return Z_DATA_ERROR;
|
|
s->mode = TYPE;
|
|
return Z_OK;
|
|
}
|
|
|
|
|
|
/*+++++*/
|
|
/* inftrees.c -- generate Huffman trees for efficient decoding
|
|
* Copyright (C) 1995 Mark Adler
|
|
* For conditions of distribution and use, see copyright notice in zlib.h
|
|
*/
|
|
|
|
/* simplify the use of the inflate_huft type with some defines */
|
|
#define base more.Base
|
|
#define next more.Next
|
|
#define exop word.what.Exop
|
|
#define bits word.what.Bits
|
|
|
|
|
|
local int huft_build OF((
|
|
uIntf *, /* code lengths in bits */
|
|
uInt, /* number of codes */
|
|
uInt, /* number of "simple" codes */
|
|
uIntf *, /* list of base values for non-simple codes */
|
|
uIntf *, /* list of extra bits for non-simple codes */
|
|
inflate_huft * FAR*,/* result: starting table */
|
|
uIntf *, /* maximum lookup bits (returns actual) */
|
|
z_stream *)); /* for zalloc function */
|
|
|
|
local voidpf falloc OF((
|
|
voidpf, /* opaque pointer (not used) */
|
|
uInt, /* number of items */
|
|
uInt)); /* size of item */
|
|
|
|
local void ffree OF((
|
|
voidpf q, /* opaque pointer (not used) */
|
|
voidpf p, /* what to free (not used) */
|
|
uInt n)); /* number of bytes (not used) */
|
|
|
|
/* Tables for deflate from PKZIP's appnote.txt. */
|
|
local uInt cplens[] = { /* Copy lengths for literal codes 257..285 */
|
|
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};
|
|
/* actually lengths - 2; also see note #13 above about 258 */
|
|
local uInt cplext[] = { /* Extra bits for literal codes 257..285 */
|
|
0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
|
|
3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 192, 192}; /* 192==invalid */
|
|
local uInt cpdist[] = { /* Copy offsets for distance codes 0..29 */
|
|
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};
|
|
local uInt cpdext[] = { /* Extra bits for distance codes */
|
|
0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
|
|
7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
|
|
12, 12, 13, 13};
|
|
|
|
/*
|
|
Huffman code decoding is performed using a multi-level table lookup.
|
|
The fastest way to decode is to simply build a lookup table whose
|
|
size is determined by the longest code. However, the time it takes
|
|
to build this table can also be a factor if the data being decoded
|
|
is not very long. The most common codes are necessarily the
|
|
shortest codes, so those codes dominate the decoding time, and hence
|
|
the speed. The idea is you can have a shorter table that decodes the
|
|
shorter, more probable codes, and then point to subsidiary tables for
|
|
the longer codes. The time it costs to decode the longer codes is
|
|
then traded against the time it takes to make longer tables.
|
|
|
|
This results of this trade are in the variables lbits and dbits
|
|
below. lbits is the number of bits the first level table for literal/
|
|
length codes can decode in one step, and dbits is the same thing for
|
|
the distance codes. Subsequent tables are also less than or equal to
|
|
those sizes. These values may be adjusted either when all of the
|
|
codes are shorter than that, in which case the longest code length in
|
|
bits is used, or when the shortest code is *longer* than the requested
|
|
table size, in which case the length of the shortest code in bits is
|
|
used.
|
|
|
|
There are two different values for the two tables, since they code a
|
|
different number of possibilities each. The literal/length table
|
|
codes 286 possible values, or in a flat code, a little over eight
|
|
bits. The distance table codes 30 possible values, or a little less
|
|
than five bits, flat. The optimum values for speed end up being
|
|
about one bit more than those, so lbits is 8+1 and dbits is 5+1.
|
|
The optimum values may differ though from machine to machine, and
|
|
possibly even between compilers. Your mileage may vary.
|
|
*/
|
|
|
|
|
|
/* If BMAX needs to be larger than 16, then h and x[] should be uLong. */
|
|
#define BMAX 15 /* maximum bit length of any code */
|
|
#define N_MAX 288 /* maximum number of codes in any set */
|
|
|
|
#ifdef DEBUG_ZLIB
|
|
uInt inflate_hufts;
|
|
#endif
|
|
|
|
local int huft_build(
|
|
uIntf *b, /* code lengths in bits (all assumed <= BMAX) */
|
|
uInt n, /* number of codes (assumed <= N_MAX) */
|
|
uInt s, /* number of simple-valued codes (0..s-1) */
|
|
uIntf *d, /* list of base values for non-simple codes */
|
|
uIntf *e, /* list of extra bits for non-simple codes */
|
|
inflate_huft * FAR *t, /* result: starting table */
|
|
uIntf *m, /* maximum lookup bits, returns actual */
|
|
z_stream *zs /* for zalloc function */
|
|
)
|
|
/* Given a list of code lengths and a maximum table size, make a set of
|
|
tables to decode that set of codes. Return Z_OK on success, Z_BUF_ERROR
|
|
if the given code set is incomplete (the tables are still built in this
|
|
case), Z_DATA_ERROR if the input is invalid (all zero length codes or an
|
|
over-subscribed set of lengths), or Z_MEM_ERROR if not enough memory. */
|
|
{
|
|
|
|
uInt a; /* counter for codes of length k */
|
|
uInt c[BMAX+1]; /* bit length count table */
|
|
uInt f; /* i repeats in table every f entries */
|
|
int g; /* maximum code length */
|
|
int h; /* table level */
|
|
register uInt i; /* counter, current code */
|
|
register uInt j; /* counter */
|
|
register int k; /* number of bits in current code */
|
|
int l; /* bits per table (returned in m) */
|
|
register uIntf *p; /* pointer into c[], b[], or v[] */
|
|
inflate_huft *q; /* points to current table */
|
|
struct inflate_huft_s r; /* table entry for structure assignment */
|
|
inflate_huft *u[BMAX]; /* table stack */
|
|
uInt v[N_MAX]; /* values in order of bit length */
|
|
register int w; /* bits before this table == (l * h) */
|
|
uInt x[BMAX+1]; /* bit offsets, then code stack */
|
|
uIntf *xp; /* pointer into x */
|
|
int y; /* number of dummy codes added */
|
|
uInt z; /* number of entries in current table */
|
|
|
|
|
|
/* Generate counts for each bit length */
|
|
p = c;
|
|
#define C0 *p++ = 0;
|
|
#define C2 C0 C0 C0 C0
|
|
#define C4 C2 C2 C2 C2
|
|
C4 /* clear c[]--assume BMAX+1 is 16 */
|
|
p = b; i = n;
|
|
do {
|
|
c[*p++]++; /* assume all entries <= BMAX */
|
|
} while (--i);
|
|
if (c[0] == n) /* null input--all zero length codes */
|
|
{
|
|
*t = (inflate_huft *)Z_NULL;
|
|
*m = 0;
|
|
return Z_OK;
|
|
}
|
|
|
|
|
|
/* Find minimum and maximum length, bound *m by those */
|
|
l = *m;
|
|
for (j = 1; j <= BMAX; j++)
|
|
if (c[j])
|
|
break;
|
|
k = j; /* minimum code length */
|
|
if ((uInt)l < j)
|
|
l = j;
|
|
for (i = BMAX; i; i--)
|
|
if (c[i])
|
|
break;
|
|
g = i; /* maximum code length */
|
|
if ((uInt)l > i)
|
|
l = i;
|
|
*m = l;
|
|
|
|
|
|
/* Adjust last length count to fill out codes, if needed */
|
|
for (y = 1 << j; j < i; j++, y <<= 1)
|
|
if ((y -= c[j]) < 0)
|
|
return Z_DATA_ERROR;
|
|
if ((y -= c[i]) < 0)
|
|
return Z_DATA_ERROR;
|
|
c[i] += y;
|
|
|
|
|
|
/* Generate starting offsets into the value table for each length */
|
|
x[1] = j = 0;
|
|
p = c + 1; xp = x + 2;
|
|
while (--i) { /* note that i == g from above */
|
|
*xp++ = (j += *p++);
|
|
}
|
|
|
|
|
|
/* Make a table of values in order of bit lengths */
|
|
p = b; i = 0;
|
|
do {
|
|
if ((j = *p++) != 0)
|
|
v[x[j]++] = i;
|
|
} while (++i < n);
|
|
|
|
|
|
/* Generate the Huffman codes and for each, make the table entries */
|
|
x[0] = i = 0; /* first Huffman code is zero */
|
|
p = v; /* grab values in bit order */
|
|
h = -1; /* no tables yet--level -1 */
|
|
w = -l; /* bits decoded == (l * h) */
|
|
u[0] = (inflate_huft *)Z_NULL; /* just to keep compilers happy */
|
|
q = (inflate_huft *)Z_NULL; /* ditto */
|
|
z = 0; /* ditto */
|
|
|
|
/* go through the bit lengths (k already is bits in shortest code) */
|
|
for (; k <= g; k++)
|
|
{
|
|
a = c[k];
|
|
while (a--)
|
|
{
|
|
/* here i is the Huffman code of length k bits for value *p */
|
|
/* make tables up to required level */
|
|
while (k > w + l)
|
|
{
|
|
h++;
|
|
w += l; /* previous table always l bits */
|
|
|
|
/* compute minimum size table less than or equal to l bits */
|
|
z = (z = g - w) > (uInt)l ? l : z; /* table size upper limit */
|
|
if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */
|
|
{ /* too few codes for k-w bit table */
|
|
f -= a + 1; /* deduct codes from patterns left */
|
|
xp = c + k;
|
|
if (j < z)
|
|
while (++j < z) /* try smaller tables up to z bits */
|
|
{
|
|
if ((f <<= 1) <= *++xp)
|
|
break; /* enough codes to use up j bits */
|
|
f -= *xp; /* else deduct codes from patterns */
|
|
}
|
|
}
|
|
z = 1 << j; /* table entries for j-bit table */
|
|
|
|
/* allocate and link in new table */
|
|
if ((q = (inflate_huft *)ZALLOC
|
|
(zs,z + 1,sizeof(inflate_huft))) == Z_NULL)
|
|
{
|
|
if (h)
|
|
inflate_trees_free(u[0], zs);
|
|
return Z_MEM_ERROR; /* not enough memory */
|
|
}
|
|
q->word.Nalloc = z + 1;
|
|
#ifdef DEBUG_ZLIB
|
|
inflate_hufts += z + 1;
|
|
#endif
|
|
*t = q + 1; /* link to list for huft_free() */
|
|
*(t = &(q->next)) = Z_NULL;
|
|
u[h] = ++q; /* table starts after link */
|
|
|
|
/* connect to last table, if there is one */
|
|
if (h)
|
|
{
|
|
x[h] = i; /* save pattern for backing up */
|
|
r.bits = (Byte)l; /* bits to dump before this table */
|
|
r.exop = (Byte)j; /* bits in this table */
|
|
r.next = q; /* pointer to this table */
|
|
j = i >> (w - l); /* (get around Turbo C bug) */
|
|
u[h-1][j] = r; /* connect to last table */
|
|
}
|
|
}
|
|
|
|
/* set up table entry in r */
|
|
r.bits = (Byte)(k - w);
|
|
if (p >= v + n)
|
|
r.exop = 128 + 64; /* out of values--invalid code */
|
|
else if (*p < s)
|
|
{
|
|
r.exop = (Byte)(*p < 256 ? 0 : 32 + 64); /* 256 is end-of-block */
|
|
r.base = *p++; /* simple code is just the value */
|
|
}
|
|
else
|
|
{
|
|
r.exop = (Byte)e[*p - s] + 16 + 64; /* non-simple--look up in lists */
|
|
r.base = d[*p++ - s];
|
|
}
|
|
|
|
/* fill code-like entries with r */
|
|
f = 1 << (k - w);
|
|
for (j = i >> w; j < z; j += f)
|
|
q[j] = r;
|
|
|
|
/* backwards increment the k-bit code i */
|
|
for (j = 1 << (k - 1); i & j; j >>= 1)
|
|
i ^= j;
|
|
i ^= j;
|
|
|
|
/* backup over finished tables */
|
|
while ((i & ((1 << w) - 1)) != x[h])
|
|
{
|
|
h--; /* don't need to update q */
|
|
w -= l;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/* Return Z_BUF_ERROR if we were given an incomplete table */
|
|
return y != 0 && g != 1 ? Z_BUF_ERROR : Z_OK;
|
|
}
|
|
|
|
|
|
local int inflate_trees_bits(
|
|
uIntf *c, /* 19 code lengths */
|
|
uIntf *bb, /* bits tree desired/actual depth */
|
|
inflate_huft * FAR *tb, /* bits tree result */
|
|
z_stream *z /* for zfree function */
|
|
)
|
|
{
|
|
int r;
|
|
|
|
r = huft_build(c, 19, 19, (uIntf*)Z_NULL, (uIntf*)Z_NULL, tb, bb, z);
|
|
if (r == Z_DATA_ERROR)
|
|
z->msg = "oversubscribed dynamic bit lengths tree";
|
|
else if (r == Z_BUF_ERROR)
|
|
{
|
|
inflate_trees_free(*tb, z);
|
|
z->msg = "incomplete dynamic bit lengths tree";
|
|
r = Z_DATA_ERROR;
|
|
}
|
|
return r;
|
|
}
|
|
|
|
|
|
local int inflate_trees_dynamic(
|
|
uInt nl, /* number of literal/length codes */
|
|
uInt nd, /* number of distance codes */
|
|
uIntf *c, /* that many (total) code lengths */
|
|
uIntf *bl, /* literal desired/actual bit depth */
|
|
uIntf *bd, /* distance desired/actual bit depth */
|
|
inflate_huft * FAR *tl, /* literal/length tree result */
|
|
inflate_huft * FAR *td, /* distance tree result */
|
|
z_stream *z /* for zfree function */
|
|
)
|
|
{
|
|
int r;
|
|
|
|
/* build literal/length tree */
|
|
if ((r = huft_build(c, nl, 257, cplens, cplext, tl, bl, z)) != Z_OK)
|
|
{
|
|
if (r == Z_DATA_ERROR)
|
|
z->msg = "oversubscribed literal/length tree";
|
|
else if (r == Z_BUF_ERROR)
|
|
{
|
|
inflate_trees_free(*tl, z);
|
|
z->msg = "incomplete literal/length tree";
|
|
r = Z_DATA_ERROR;
|
|
}
|
|
return r;
|
|
}
|
|
|
|
/* build distance tree */
|
|
if ((r = huft_build(c + nl, nd, 0, cpdist, cpdext, td, bd, z)) != Z_OK)
|
|
{
|
|
if (r == Z_DATA_ERROR)
|
|
z->msg = "oversubscribed literal/length tree";
|
|
else if (r == Z_BUF_ERROR) {
|
|
#ifdef PKZIP_BUG_WORKAROUND
|
|
r = Z_OK;
|
|
}
|
|
#else
|
|
inflate_trees_free(*td, z);
|
|
z->msg = "incomplete literal/length tree";
|
|
r = Z_DATA_ERROR;
|
|
}
|
|
inflate_trees_free(*tl, z);
|
|
return r;
|
|
#endif
|
|
}
|
|
|
|
/* done */
|
|
return Z_OK;
|
|
}
|
|
|
|
|
|
/* build fixed tables only once--keep them here */
|
|
local int fixed_lock = 0;
|
|
local int fixed_built = 0;
|
|
#define FIXEDH 530 /* number of hufts used by fixed tables */
|
|
local uInt fixed_left = FIXEDH;
|
|
local inflate_huft fixed_mem[FIXEDH];
|
|
local uInt fixed_bl;
|
|
local uInt fixed_bd;
|
|
local inflate_huft *fixed_tl;
|
|
local inflate_huft *fixed_td;
|
|
|
|
|
|
local voidpf falloc(
|
|
voidpf q, /* opaque pointer (not used) */
|
|
uInt n, /* number of items */
|
|
uInt s /* size of item */
|
|
)
|
|
{
|
|
Assert(s == sizeof(inflate_huft) && n <= fixed_left,
|
|
"inflate_trees falloc overflow");
|
|
if (q) s++; /* to make some compilers happy */
|
|
fixed_left -= n;
|
|
return (voidpf)(fixed_mem + fixed_left);
|
|
}
|
|
|
|
|
|
local void ffree(
|
|
voidpf q,
|
|
voidpf p,
|
|
uInt n
|
|
)
|
|
{
|
|
Assert(0, "inflate_trees ffree called!");
|
|
if (q) q = p; /* to make some compilers happy */
|
|
}
|
|
|
|
|
|
local int inflate_trees_fixed(
|
|
uIntf *bl, /* literal desired/actual bit depth */
|
|
uIntf *bd, /* distance desired/actual bit depth */
|
|
inflate_huft * FAR *tl, /* literal/length tree result */
|
|
inflate_huft * FAR *td /* distance tree result */
|
|
)
|
|
{
|
|
/* build fixed tables if not built already--lock out other instances */
|
|
while (++fixed_lock > 1)
|
|
fixed_lock--;
|
|
if (!fixed_built)
|
|
{
|
|
int k; /* temporary variable */
|
|
unsigned c[288]; /* length list for huft_build */
|
|
z_stream z; /* for falloc function */
|
|
|
|
/* set up fake z_stream for memory routines */
|
|
z.zalloc = falloc;
|
|
z.zfree = ffree;
|
|
z.opaque = Z_NULL;
|
|
|
|
/* literal table */
|
|
for (k = 0; k < 144; k++)
|
|
c[k] = 8;
|
|
for (; k < 256; k++)
|
|
c[k] = 9;
|
|
for (; k < 280; k++)
|
|
c[k] = 7;
|
|
for (; k < 288; k++)
|
|
c[k] = 8;
|
|
fixed_bl = 7;
|
|
huft_build(c, 288, 257, cplens, cplext, &fixed_tl, &fixed_bl, &z);
|
|
|
|
/* distance table */
|
|
for (k = 0; k < 30; k++)
|
|
c[k] = 5;
|
|
fixed_bd = 5;
|
|
huft_build(c, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd, &z);
|
|
|
|
/* done */
|
|
fixed_built = 1;
|
|
}
|
|
fixed_lock--;
|
|
*bl = fixed_bl;
|
|
*bd = fixed_bd;
|
|
*tl = fixed_tl;
|
|
*td = fixed_td;
|
|
return Z_OK;
|
|
}
|
|
|
|
|
|
local int inflate_trees_free(
|
|
inflate_huft *t, /* table to free */
|
|
z_stream *z /* for zfree function */
|
|
)
|
|
/* Free the malloc'ed tables built by huft_build(), which makes a linked
|
|
list of the tables it made, with the links in a dummy first entry of
|
|
each table. */
|
|
{
|
|
register inflate_huft *p, *q;
|
|
|
|
/* Go through linked list, freeing from the malloced (t[-1]) address. */
|
|
p = t;
|
|
while (p != Z_NULL)
|
|
{
|
|
q = (--p)->next;
|
|
ZFREE(z, p, p->word.Nalloc * sizeof(inflate_huft));
|
|
p = q;
|
|
}
|
|
return Z_OK;
|
|
}
|
|
|
|
/*+++++*/
|
|
/* infcodes.c -- process literals and length/distance pairs
|
|
* Copyright (C) 1995 Mark Adler
|
|
* For conditions of distribution and use, see copyright notice in zlib.h
|
|
*/
|
|
|
|
/* simplify the use of the inflate_huft type with some defines */
|
|
#define base more.Base
|
|
#define next more.Next
|
|
#define exop word.what.Exop
|
|
#define bits word.what.Bits
|
|
|
|
/* inflate codes private state */
|
|
struct inflate_codes_state {
|
|
|
|
/* mode */
|
|
enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
|
|
START, /* x: set up for LEN */
|
|
LEN, /* i: get length/literal/eob next */
|
|
LENEXT, /* i: getting length extra (have base) */
|
|
DIST, /* i: get distance next */
|
|
DISTEXT, /* i: getting distance extra */
|
|
COPY, /* o: copying bytes in window, waiting for space */
|
|
LIT, /* o: got literal, waiting for output space */
|
|
WASH, /* o: got eob, possibly still output waiting */
|
|
END, /* x: got eob and all data flushed */
|
|
BADCODE} /* x: got error */
|
|
mode; /* current inflate_codes mode */
|
|
|
|
/* mode dependent information */
|
|
uInt len;
|
|
union {
|
|
struct {
|
|
inflate_huft *tree; /* pointer into tree */
|
|
uInt need; /* bits needed */
|
|
} code; /* if LEN or DIST, where in tree */
|
|
uInt lit; /* if LIT, literal */
|
|
struct {
|
|
uInt get; /* bits to get for extra */
|
|
uInt dist; /* distance back to copy from */
|
|
} copy; /* if EXT or COPY, where and how much */
|
|
} sub; /* submode */
|
|
|
|
/* mode independent information */
|
|
Byte lbits; /* ltree bits decoded per branch */
|
|
Byte dbits; /* dtree bits decoder per branch */
|
|
inflate_huft *ltree; /* literal/length/eob tree */
|
|
inflate_huft *dtree; /* distance tree */
|
|
|
|
};
|
|
|
|
|
|
local inflate_codes_statef *inflate_codes_new(
|
|
uInt bl,
|
|
uInt bd,
|
|
inflate_huft *tl,
|
|
inflate_huft *td,
|
|
z_stream *z
|
|
)
|
|
{
|
|
inflate_codes_statef *c;
|
|
|
|
if ((c = (inflate_codes_statef *)
|
|
ZALLOC(z,1,sizeof(struct inflate_codes_state))) != Z_NULL)
|
|
{
|
|
c->mode = START;
|
|
c->lbits = (Byte)bl;
|
|
c->dbits = (Byte)bd;
|
|
c->ltree = tl;
|
|
c->dtree = td;
|
|
Tracev((stderr, "inflate: codes new\n"));
|
|
}
|
|
return c;
|
|
}
|
|
|
|
|
|
local int inflate_codes(
|
|
inflate_blocks_statef *s,
|
|
z_stream *z,
|
|
int r
|
|
)
|
|
{
|
|
uInt j; /* temporary storage */
|
|
inflate_huft *t; /* temporary pointer */
|
|
uInt e; /* extra bits or operation */
|
|
uLong b; /* bit buffer */
|
|
uInt k; /* bits in bit buffer */
|
|
Bytef *p; /* input data pointer */
|
|
uInt n; /* bytes available there */
|
|
Bytef *q; /* output window write pointer */
|
|
uInt m; /* bytes to end of window or read pointer */
|
|
Bytef *f; /* pointer to copy strings from */
|
|
inflate_codes_statef *c = s->sub.decode.codes; /* codes state */
|
|
|
|
/* copy input/output information to locals (UPDATE macro restores) */
|
|
LOAD
|
|
|
|
/* process input and output based on current state */
|
|
while (1) switch (c->mode)
|
|
{ /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
|
|
case START: /* x: set up for LEN */
|
|
#ifndef SLOW
|
|
if (m >= 258 && n >= 10)
|
|
{
|
|
UPDATE
|
|
r = inflate_fast(c->lbits, c->dbits, c->ltree, c->dtree, s, z);
|
|
LOAD
|
|
if (r != Z_OK)
|
|
{
|
|
c->mode = r == Z_STREAM_END ? WASH : BADCODE;
|
|
break;
|
|
}
|
|
}
|
|
#endif /* !SLOW */
|
|
c->sub.code.need = c->lbits;
|
|
c->sub.code.tree = c->ltree;
|
|
c->mode = LEN;
|
|
case LEN: /* i: get length/literal/eob next */
|
|
j = c->sub.code.need;
|
|
NEEDBITS(j)
|
|
t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
|
|
DUMPBITS(t->bits)
|
|
e = (uInt)(t->exop);
|
|
if (e == 0) /* literal */
|
|
{
|
|
c->sub.lit = t->base;
|
|
Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
|
|
"inflate: literal '%c'\n" :
|
|
"inflate: literal 0x%02x\n", t->base));
|
|
c->mode = LIT;
|
|
break;
|
|
}
|
|
if (e & 16) /* length */
|
|
{
|
|
c->sub.copy.get = e & 15;
|
|
c->len = t->base;
|
|
c->mode = LENEXT;
|
|
break;
|
|
}
|
|
if ((e & 64) == 0) /* next table */
|
|
{
|
|
c->sub.code.need = e;
|
|
c->sub.code.tree = t->next;
|
|
break;
|
|
}
|
|
if (e & 32) /* end of block */
|
|
{
|
|
Tracevv((stderr, "inflate: end of block\n"));
|
|
c->mode = WASH;
|
|
break;
|
|
}
|
|
c->mode = BADCODE; /* invalid code */
|
|
z->msg = "invalid literal/length code";
|
|
r = Z_DATA_ERROR;
|
|
LEAVE
|
|
case LENEXT: /* i: getting length extra (have base) */
|
|
j = c->sub.copy.get;
|
|
NEEDBITS(j)
|
|
c->len += (uInt)b & inflate_mask[j];
|
|
DUMPBITS(j)
|
|
c->sub.code.need = c->dbits;
|
|
c->sub.code.tree = c->dtree;
|
|
Tracevv((stderr, "inflate: length %u\n", c->len));
|
|
c->mode = DIST;
|
|
case DIST: /* i: get distance next */
|
|
j = c->sub.code.need;
|
|
NEEDBITS(j)
|
|
t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
|
|
DUMPBITS(t->bits)
|
|
e = (uInt)(t->exop);
|
|
if (e & 16) /* distance */
|
|
{
|
|
c->sub.copy.get = e & 15;
|
|
c->sub.copy.dist = t->base;
|
|
c->mode = DISTEXT;
|
|
break;
|
|
}
|
|
if ((e & 64) == 0) /* next table */
|
|
{
|
|
c->sub.code.need = e;
|
|
c->sub.code.tree = t->next;
|
|
break;
|
|
}
|
|
c->mode = BADCODE; /* invalid code */
|
|
z->msg = "invalid distance code";
|
|
r = Z_DATA_ERROR;
|
|
LEAVE
|
|
case DISTEXT: /* i: getting distance extra */
|
|
j = c->sub.copy.get;
|
|
NEEDBITS(j)
|
|
c->sub.copy.dist += (uInt)b & inflate_mask[j];
|
|
DUMPBITS(j)
|
|
Tracevv((stderr, "inflate: distance %u\n", c->sub.copy.dist));
|
|
c->mode = COPY;
|
|
case COPY: /* o: copying bytes in window, waiting for space */
|
|
#ifndef __TURBOC__ /* Turbo C bug for following expression */
|
|
f = (uInt)(q - s->window) < c->sub.copy.dist ?
|
|
s->end - (c->sub.copy.dist - (q - s->window)) :
|
|
q - c->sub.copy.dist;
|
|
#else
|
|
f = q - c->sub.copy.dist;
|
|
if ((uInt)(q - s->window) < c->sub.copy.dist)
|
|
f = s->end - (c->sub.copy.dist - (q - s->window));
|
|
#endif
|
|
while (c->len)
|
|
{
|
|
NEEDOUT
|
|
OUTBYTE(*f++)
|
|
if (f == s->end)
|
|
f = s->window;
|
|
c->len--;
|
|
}
|
|
c->mode = START;
|
|
break;
|
|
case LIT: /* o: got literal, waiting for output space */
|
|
NEEDOUT
|
|
OUTBYTE(c->sub.lit)
|
|
c->mode = START;
|
|
break;
|
|
case WASH: /* o: got eob, possibly more output */
|
|
FLUSH
|
|
if (s->read != s->write)
|
|
LEAVE
|
|
c->mode = END;
|
|
case END:
|
|
r = Z_STREAM_END;
|
|
LEAVE
|
|
case BADCODE: /* x: got error */
|
|
r = Z_DATA_ERROR;
|
|
LEAVE
|
|
default:
|
|
r = Z_STREAM_ERROR;
|
|
LEAVE
|
|
}
|
|
}
|
|
|
|
|
|
local void inflate_codes_free(
|
|
inflate_codes_statef *c,
|
|
z_stream *z
|
|
)
|
|
{
|
|
ZFREE(z, c, sizeof(struct inflate_codes_state));
|
|
Tracev((stderr, "inflate: codes free\n"));
|
|
}
|
|
|
|
/*+++++*/
|
|
/* inflate_util.c -- data and routines common to blocks and codes
|
|
* Copyright (C) 1995 Mark Adler
|
|
* For conditions of distribution and use, see copyright notice in zlib.h
|
|
*/
|
|
|
|
/* copy as much as possible from the sliding window to the output area */
|
|
local int inflate_flush(
|
|
inflate_blocks_statef *s,
|
|
z_stream *z,
|
|
int r
|
|
)
|
|
{
|
|
uInt n;
|
|
Bytef *p, *q;
|
|
|
|
/* local copies of source and destination pointers */
|
|
p = z->next_out;
|
|
q = s->read;
|
|
|
|
/* compute number of bytes to copy as far as end of window */
|
|
n = (uInt)((q <= s->write ? s->write : s->end) - q);
|
|
if (n > z->avail_out) n = z->avail_out;
|
|
if (n && r == Z_BUF_ERROR) r = Z_OK;
|
|
|
|
/* update counters */
|
|
z->avail_out -= n;
|
|
z->total_out += n;
|
|
|
|
/* update check information */
|
|
if (s->checkfn != Z_NULL)
|
|
s->check = (*s->checkfn)(s->check, q, n);
|
|
|
|
/* copy as far as end of window */
|
|
zmemcpy(p, q, n);
|
|
p += n;
|
|
q += n;
|
|
|
|
/* see if more to copy at beginning of window */
|
|
if (q == s->end)
|
|
{
|
|
/* wrap pointers */
|
|
q = s->window;
|
|
if (s->write == s->end)
|
|
s->write = s->window;
|
|
|
|
/* compute bytes to copy */
|
|
n = (uInt)(s->write - q);
|
|
if (n > z->avail_out) n = z->avail_out;
|
|
if (n && r == Z_BUF_ERROR) r = Z_OK;
|
|
|
|
/* update counters */
|
|
z->avail_out -= n;
|
|
z->total_out += n;
|
|
|
|
/* update check information */
|
|
if (s->checkfn != Z_NULL)
|
|
s->check = (*s->checkfn)(s->check, q, n);
|
|
|
|
/* copy */
|
|
zmemcpy(p, q, n);
|
|
p += n;
|
|
q += n;
|
|
}
|
|
|
|
/* update pointers */
|
|
z->next_out = p;
|
|
s->read = q;
|
|
|
|
/* done */
|
|
return r;
|
|
}
|
|
|
|
|
|
/*+++++*/
|
|
/* inffast.c -- process literals and length/distance pairs fast
|
|
* Copyright (C) 1995 Mark Adler
|
|
* For conditions of distribution and use, see copyright notice in zlib.h
|
|
*/
|
|
|
|
/* simplify the use of the inflate_huft type with some defines */
|
|
#define base more.Base
|
|
#define next more.Next
|
|
#define exop word.what.Exop
|
|
#define bits word.what.Bits
|
|
|
|
/* macros for bit input with no checking and for returning unused bytes */
|
|
#define GRABBITS(j) {while(k<(j)){b|=((uLong)NEXTBYTE)<<k;k+=8;}}
|
|
#define UNGRAB {n+=(c=k>>3);p-=c;k&=7;}
|
|
|
|
/* Called with number of bytes left to write in window at least 258
|
|
(the maximum string length) and number of input bytes available
|
|
at least ten. The ten bytes are six bytes for the longest length/
|
|
distance pair plus four bytes for overloading the bit buffer. */
|
|
|
|
local int inflate_fast(
|
|
uInt bl,
|
|
uInt bd,
|
|
inflate_huft *tl,
|
|
inflate_huft *td,
|
|
inflate_blocks_statef *s,
|
|
z_stream *z
|
|
)
|
|
{
|
|
inflate_huft *t; /* temporary pointer */
|
|
uInt e; /* extra bits or operation */
|
|
uLong b; /* bit buffer */
|
|
uInt k; /* bits in bit buffer */
|
|
Bytef *p; /* input data pointer */
|
|
uInt n; /* bytes available there */
|
|
Bytef *q; /* output window write pointer */
|
|
uInt m; /* bytes to end of window or read pointer */
|
|
uInt ml; /* mask for literal/length tree */
|
|
uInt md; /* mask for distance tree */
|
|
uInt c; /* bytes to copy */
|
|
uInt d; /* distance back to copy from */
|
|
Bytef *r; /* copy source pointer */
|
|
|
|
/* load input, output, bit values */
|
|
LOAD
|
|
|
|
/* initialize masks */
|
|
ml = inflate_mask[bl];
|
|
md = inflate_mask[bd];
|
|
|
|
/* do until not enough input or output space for fast loop */
|
|
do { /* assume called with m >= 258 && n >= 10 */
|
|
/* get literal/length code */
|
|
GRABBITS(20) /* max bits for literal/length code */
|
|
if ((e = (t = tl + ((uInt)b & ml))->exop) == 0)
|
|
{
|
|
DUMPBITS(t->bits)
|
|
Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
|
|
"inflate: * literal '%c'\n" :
|
|
"inflate: * literal 0x%02x\n", t->base));
|
|
*q++ = (Byte)t->base;
|
|
m--;
|
|
continue;
|
|
}
|
|
do {
|
|
DUMPBITS(t->bits)
|
|
if (e & 16)
|
|
{
|
|
/* get extra bits for length */
|
|
e &= 15;
|
|
c = t->base + ((uInt)b & inflate_mask[e]);
|
|
DUMPBITS(e)
|
|
Tracevv((stderr, "inflate: * length %u\n", c));
|
|
|
|
/* decode distance base of block to copy */
|
|
GRABBITS(15); /* max bits for distance code */
|
|
e = (t = td + ((uInt)b & md))->exop;
|
|
do {
|
|
DUMPBITS(t->bits)
|
|
if (e & 16)
|
|
{
|
|
/* get extra bits to add to distance base */
|
|
e &= 15;
|
|
GRABBITS(e) /* get extra bits (up to 13) */
|
|
d = t->base + ((uInt)b & inflate_mask[e]);
|
|
DUMPBITS(e)
|
|
Tracevv((stderr, "inflate: * distance %u\n", d));
|
|
|
|
/* do the copy */
|
|
m -= c;
|
|
if ((uInt)(q - s->window) >= d) /* offset before dest */
|
|
{ /* just copy */
|
|
r = q - d;
|
|
*q++ = *r++; c--; /* minimum count is three, */
|
|
*q++ = *r++; c--; /* so unroll loop a little */
|
|
}
|
|
else /* else offset after destination */
|
|
{
|
|
e = d - (q - s->window); /* bytes from offset to end */
|
|
r = s->end - e; /* pointer to offset */
|
|
if (c > e) /* if source crosses, */
|
|
{
|
|
c -= e; /* copy to end of window */
|
|
do {
|
|
*q++ = *r++;
|
|
} while (--e);
|
|
r = s->window; /* copy rest from start of window */
|
|
}
|
|
}
|
|
do { /* copy all or what's left */
|
|
*q++ = *r++;
|
|
} while (--c);
|
|
break;
|
|
}
|
|
else if ((e & 64) == 0)
|
|
e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop;
|
|
else
|
|
{
|
|
z->msg = "invalid distance code";
|
|
UNGRAB
|
|
UPDATE
|
|
return Z_DATA_ERROR;
|
|
}
|
|
} while (1);
|
|
break;
|
|
}
|
|
if ((e & 64) == 0)
|
|
{
|
|
if ((e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop) == 0)
|
|
{
|
|
DUMPBITS(t->bits)
|
|
Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
|
|
"inflate: * literal '%c'\n" :
|
|
"inflate: * literal 0x%02x\n", t->base));
|
|
*q++ = (Byte)t->base;
|
|
m--;
|
|
break;
|
|
}
|
|
}
|
|
else if (e & 32)
|
|
{
|
|
Tracevv((stderr, "inflate: * end of block\n"));
|
|
UNGRAB
|
|
UPDATE
|
|
return Z_STREAM_END;
|
|
}
|
|
else
|
|
{
|
|
z->msg = "invalid literal/length code";
|
|
UNGRAB
|
|
UPDATE
|
|
return Z_DATA_ERROR;
|
|
}
|
|
} while (1);
|
|
} while (m >= 258 && n >= 10);
|
|
|
|
/* not enough input or output--restore pointers and return */
|
|
UNGRAB
|
|
UPDATE
|
|
return Z_OK;
|
|
}
|
|
|
|
|
|
/*+++++*/
|
|
/* zutil.c -- target dependent utility functions for the compression library
|
|
* Copyright (C) 1995 Jean-loup Gailly.
|
|
* For conditions of distribution and use, see copyright notice in zlib.h
|
|
*/
|
|
|
|
/* From: zutil.c,v 1.8 1995/05/03 17:27:12 jloup Exp */
|
|
|
|
char *zlib_version = ZLIB_VERSION;
|
|
|
|
char *z_errmsg[] = {
|
|
"stream end", /* Z_STREAM_END 1 */
|
|
"", /* Z_OK 0 */
|
|
"file error", /* Z_ERRNO (-1) */
|
|
"stream error", /* Z_STREAM_ERROR (-2) */
|
|
"data error", /* Z_DATA_ERROR (-3) */
|
|
"insufficient memory", /* Z_MEM_ERROR (-4) */
|
|
"buffer error", /* Z_BUF_ERROR (-5) */
|
|
""};
|
|
|
|
|
|
/*+++++*/
|
|
/* adler32.c -- compute the Adler-32 checksum of a data stream
|
|
* Copyright (C) 1995 Mark Adler
|
|
* For conditions of distribution and use, see copyright notice in zlib.h
|
|
*/
|
|
|
|
/* From: adler32.c,v 1.6 1995/05/03 17:27:08 jloup Exp */
|
|
|
|
#define BASE 65521L /* largest prime smaller than 65536 */
|
|
#define NMAX 5552
|
|
/* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
|
|
|
|
#define DO1(buf) {s1 += *buf++; s2 += s1;}
|
|
#define DO2(buf) DO1(buf); DO1(buf);
|
|
#define DO4(buf) DO2(buf); DO2(buf);
|
|
#define DO8(buf) DO4(buf); DO4(buf);
|
|
#define DO16(buf) DO8(buf); DO8(buf);
|
|
|
|
/* ========================================================================= */
|
|
uLong adler32(
|
|
uLong adler,
|
|
Bytef *buf,
|
|
uInt len
|
|
)
|
|
{
|
|
unsigned long s1 = adler & 0xffff;
|
|
unsigned long s2 = (adler >> 16) & 0xffff;
|
|
int k;
|
|
|
|
if (buf == Z_NULL) return 1L;
|
|
|
|
while (len > 0) {
|
|
k = len < NMAX ? len : NMAX;
|
|
len -= k;
|
|
while (k >= 16) {
|
|
DO16(buf);
|
|
k -= 16;
|
|
}
|
|
if (k != 0) do {
|
|
DO1(buf);
|
|
} while (--k);
|
|
s1 %= BASE;
|
|
s2 %= BASE;
|
|
}
|
|
return (s2 << 16) | s1;
|
|
}
|
|
|