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/* blast.c
* Copyright (C) 2003 Mark Adler
* For conditions of distribution and use, see copyright notice in blast.h
* version 1.1, 16 Feb 2003
*
* blast.c decompresses data compressed by the PKWare Compression Library.
* This function provides functionality similar to the explode() function of
* the PKWare library, hence the name "blast".
*
* This decompressor is based on the excellent format description provided by
* Ben Rudiak-Gould in comp.compression on August 13, 2001. Interestingly, the
* example Ben provided in the post is incorrect. The distance 110001 should
* instead be 111000. When corrected, the example byte stream becomes:
*
* 00 04 82 24 25 8f 80 7f
*
* which decompresses to "AIAIAIAIAIAIA" (without the quotes).
*/
/*
* Change history:
*
* 1.0 12 Feb 2003 - First version
* 1.1 16 Feb 2003 - Fixed distance check for > 4 GB uncompressed data
*/
#include <setjmp.h> /* for setjmp(), longjmp(), and jmp_buf */
#include "blast.h" /* prototype for blast() */
#define local static /* for local function definitions */
#define MAXBITS 13 /* maximum code length */
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/* blast.c
* Copyright (C) 2003, 2012 Mark Adler
* For conditions of distribution and use, see copyright notice in blast.h
* version 1.2, 24 Oct 2012
*
* blast.c decompresses data compressed by the PKWare Compression Library.
* This function provides functionality similar to the explode() function of
* the PKWare library, hence the name "blast".
*
* This decompressor is based on the excellent format description provided by
* Ben Rudiak-Gould in comp.compression on August 13, 2001. Interestingly, the
* example Ben provided in the post is incorrect. The distance 110001 should
* instead be 111000. When corrected, the example byte stream becomes:
*
* 00 04 82 24 25 8f 80 7f
*
* which decompresses to "AIAIAIAIAIAIA" (without the quotes).
*/
/*
* Change history:
*
* 1.0 12 Feb 2003 - First version
* 1.1 16 Feb 2003 - Fixed distance check for > 4 GB uncompressed data
* 1.2 24 Oct 2012 - Add note about using binary mode in stdio
* - Fix comparisons of differently signed integers
*/
#include <setjmp.h> /* for setjmp(), longjmp(), and jmp_buf */
#include "blast.h" /* prototype for blast() */
#define local static /* for local function definitions */
#define MAXBITS 13 /* maximum code length */
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*/
local int decomp(struct state *s)
{
int lit; /* true if literals are coded */
int dict; /* log2(dictionary size) - 6 */
int symbol; /* decoded symbol, extra bits for distance */
int len; /* length for copy */
int dist; /* distance for copy */
int copy; /* copy counter */
unsigned char *from, *to; /* copy pointers */
static int virgin = 1; /* build tables once */
static short litcnt[MAXBITS+1], litsym[256]; /* litcode memory */
static short lencnt[MAXBITS+1], lensym[16]; /* lencode memory */
static short distcnt[MAXBITS+1], distsym[64]; /* distcode memory */
static struct huffman litcode = {litcnt, litsym}; /* length code */
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*/
local int decomp(struct state *s)
{
int lit; /* true if literals are coded */
int dict; /* log2(dictionary size) - 6 */
int symbol; /* decoded symbol, extra bits for distance */
int len; /* length for copy */
unsigned dist; /* distance for copy */
int copy; /* copy counter */
unsigned char *from, *to; /* copy pointers */
static int virgin = 1; /* build tables once */
static short litcnt[MAXBITS+1], litsym[256]; /* litcode memory */
static short lencnt[MAXBITS+1], lensym[16]; /* lencode memory */
static short distcnt[MAXBITS+1], distsym[64]; /* distcode memory */
static struct huffman litcode = {litcnt, litsym}; /* length code */
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