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#ifndef __MICRO_BUNZIP_H__
#define __MICRO_BUNZIP_H__
/* ---- Duplicated from micro-bzip.c -------------------------------------- */
#include <setjmp.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <limits.h>
/* Constants for huffman coding */
#define MAX_GROUPS 6
#define GROUP_SIZE 50 /* 64 would have been more efficient */
#define MAX_HUFCODE_BITS 20 /* Longest huffman code allowed */
#define MAX_SYMBOLS 258 /* 256 literals + RUNA + RUNB */
#define SYMBOL_RUNA 0
#define SYMBOL_RUNB 1
/* Status return values */
#define RETVAL_OK 0
#define RETVAL_LAST_BLOCK (-1)
#define RETVAL_NOT_BZIP_DATA (-2)
#define RETVAL_UNEXPECTED_INPUT_EOF (-3)
#define RETVAL_UNEXPECTED_OUTPUT_EOF (-4)
#define RETVAL_DATA_ERROR (-5)
#define RETVAL_OUT_OF_MEMORY (-6)
#define RETVAL_OBSOLETE_INPUT (-7)
/* Other housekeeping constants */
#define IOBUF_SIZE 4096
/* This is what we know about each huffman coding group */
struct group_data
{
/* We have an extra slot at the end of limit[] for a sentinal value. */
int limit[MAX_HUFCODE_BITS+1], base[MAX_HUFCODE_BITS], permute[MAX_SYMBOLS];
int minLen, maxLen;
};
/* Structure holding all the housekeeping data, including IO buffers and
memory that persists between calls to bunzip */
typedef struct
{
/* State for interrupting output loop */
int writeCopies, writePos, writeRunCountdown, writeCount, writeCurrent;
/* I/O tracking data (file handles, buffers, positions, etc.) */
int in_fd, out_fd, inbufCount, inbufPos /*,outbufPos*/;
// james@jamestaylor.org: track relative position in input so we don't need tell
off_t position;
unsigned char *inbuf /*,*outbuf*/;
unsigned int inbufBitCount, inbufBits;
/* The CRC values stored in the block header and calculated from the data */
unsigned int crc32Table[256], headerCRC, totalCRC, writeCRC;
/* Intermediate buffer and its size (in bytes) */
unsigned int *dbuf, dbufSize;
/* These things are a bit too big to go on the stack */
unsigned char selectors[32768]; /* nSelectors=15 bits */
struct group_data groups[MAX_GROUPS]; /* huffman coding tables */
/* For I/O error handling */
jmp_buf jmpbuf;
}
bunzip_data;
static char * const bunzip_errors[] =
{
NULL, "Bad file checksum", "Not bzip data",
"Unexpected input EOF", "Unexpected output EOF", "Data error",
"Out of memory", "Obsolete (pre 0.9.5) bzip format not supported."
};
/* ---- Forward declarations for micro-bzip.c ---------------------------- */
extern int get_next_block( bunzip_data *bd );
#endif
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