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#import "CSBlockStreamHandle.h"
#import "BWT.h"
#import <stdbool.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
/* 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.) */
CSHandle *inhandle;
int inbufCount,inbufPos;
unsigned char inbuf[IOBUF_SIZE];
unsigned int inbufBitCount, inbufBits;
bool hasrand;
/* 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;
@interface XADNSISBzip2Handle:CSBlockStreamHandle
{
CSHandle *parent;
off_t startoffs;
BOOL hasrand;
bunzip_data bd;
uint32_t blocktable[900000];
uint8_t outblock[65536];
}
-(id)initWithHandle:(CSHandle *)handle length:(off_t)length hasRandomizationBit:(BOOL)hasrandbit;
-(void)dealloc;
-(void)resetBlockStream;
-(int)produceBlockAtOffset:(off_t)pos;
@end
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