busybox/archival/bz/bzlib_private.h
2008-07-05 09:18:54 +00:00

220 lines
5.2 KiB
C

/*
* bzip2 is written by Julian Seward <jseward@bzip.org>.
* Adapted for busybox by Denys Vlasenko <vda.linux@googlemail.com>.
* See README and LICENSE files in this directory for more information.
*/
/*-------------------------------------------------------------*/
/*--- Private header file for the library. ---*/
/*--- bzlib_private.h ---*/
/*-------------------------------------------------------------*/
/* ------------------------------------------------------------------
This file is part of bzip2/libbzip2, a program and library for
lossless, block-sorting data compression.
bzip2/libbzip2 version 1.0.4 of 20 December 2006
Copyright (C) 1996-2006 Julian Seward <jseward@bzip.org>
Please read the WARNING, DISCLAIMER and PATENTS sections in the
README file.
This program is released under the terms of the license contained
in the file LICENSE.
------------------------------------------------------------------ */
/* #include "bzlib.h" */
/*-- General stuff. --*/
typedef unsigned char Bool;
#define True ((Bool)1)
#define False ((Bool)0)
#if BZ_LIGHT_DEBUG
static void bz_assert_fail(int errcode) NORETURN;
#define AssertH(cond, errcode) \
do { \
if (!(cond)) \
bz_assert_fail(errcode); \
} while (0)
#else
#define AssertH(cond, msg) do { } while (0)
#endif
#if BZ_DEBUG
#define AssertD(cond, msg) \
do { \
if (!(cond)) \
bb_error_msg_and_die("(debug build): internal error %s", msg); \
} while (0)
#else
#define AssertD(cond, msg) do { } while (0)
#endif
/*-- Header bytes. --*/
#define BZ_HDR_B 0x42 /* 'B' */
#define BZ_HDR_Z 0x5a /* 'Z' */
#define BZ_HDR_h 0x68 /* 'h' */
#define BZ_HDR_0 0x30 /* '0' */
#define BZ_HDR_BZh0 0x425a6830
/*-- Constants for the back end. --*/
#define BZ_MAX_ALPHA_SIZE 258
#define BZ_MAX_CODE_LEN 23
#define BZ_RUNA 0
#define BZ_RUNB 1
#define BZ_N_GROUPS 6
#define BZ_G_SIZE 50
#define BZ_N_ITERS 4
#define BZ_MAX_SELECTORS (2 + (900000 / BZ_G_SIZE))
/*-- Stuff for doing CRCs. --*/
#define BZ_INITIALISE_CRC(crcVar) \
{ \
crcVar = 0xffffffffL; \
}
#define BZ_FINALISE_CRC(crcVar) \
{ \
crcVar = ~(crcVar); \
}
#define BZ_UPDATE_CRC(s, crcVar, cha) \
{ \
crcVar = (crcVar << 8) ^ s->crc32table[(crcVar >> 24) ^ ((uint8_t)cha)]; \
}
/*-- States and modes for compression. --*/
#define BZ_M_IDLE 1
#define BZ_M_RUNNING 2
#define BZ_M_FLUSHING 3
#define BZ_M_FINISHING 4
#define BZ_S_OUTPUT 1
#define BZ_S_INPUT 2
#define BZ_N_RADIX 2
#define BZ_N_QSORT 12
#define BZ_N_SHELL 18
#define BZ_N_OVERSHOOT (BZ_N_RADIX + BZ_N_QSORT + BZ_N_SHELL + 2)
/*-- Structure holding all the compression-side stuff. --*/
typedef struct EState {
/* pointer back to the struct bz_stream */
bz_stream *strm;
/* mode this stream is in, and whether inputting */
/* or outputting data */
int32_t mode;
int32_t state;
/* remembers avail_in when flush/finish requested */
/* bbox: not needed, strm->avail_in always has the same value */
/* commented out with '//#' throughout the code */
/* uint32_t avail_in_expect; */
/* for doing the block sorting */
int32_t origPtr;
uint32_t *arr1;
uint32_t *arr2;
uint32_t *ftab;
/* aliases for arr1 and arr2 */
uint32_t *ptr;
uint8_t *block;
uint16_t *mtfv;
uint8_t *zbits;
/* guess what */
uint32_t *crc32table;
/* run-length-encoding of the input */
uint32_t state_in_ch;
int32_t state_in_len;
/* input and output limits and current posns */
int32_t nblock;
int32_t nblockMAX;
int32_t numZ;
int32_t state_out_pos;
/* the buffer for bit stream creation */
uint32_t bsBuff;
int32_t bsLive;
/* block and combined CRCs */
uint32_t blockCRC;
uint32_t combinedCRC;
/* misc administratium */
int32_t blockNo;
int32_t blockSize100k;
/* stuff for coding the MTF values */
int32_t nMTF;
/* map of bytes used in block */
int32_t nInUse;
Bool inUse[256] ALIGNED(sizeof(long));
uint8_t unseqToSeq[256];
/* stuff for coding the MTF values */
int32_t mtfFreq [BZ_MAX_ALPHA_SIZE];
uint8_t selector [BZ_MAX_SELECTORS];
uint8_t selectorMtf[BZ_MAX_SELECTORS];
uint8_t len[BZ_N_GROUPS][BZ_MAX_ALPHA_SIZE];
/* stack-saving measures: these can be local, but they are too big */
int32_t sendMTFValues__code [BZ_N_GROUPS][BZ_MAX_ALPHA_SIZE];
int32_t sendMTFValues__rfreq[BZ_N_GROUPS][BZ_MAX_ALPHA_SIZE];
#if CONFIG_BZIP2_FEATURE_SPEED >= 5
/* second dimension: only 3 needed; 4 makes index calculations faster */
uint32_t sendMTFValues__len_pack[BZ_MAX_ALPHA_SIZE][4];
#endif
int32_t BZ2_hbMakeCodeLengths__heap [BZ_MAX_ALPHA_SIZE + 2];
int32_t BZ2_hbMakeCodeLengths__weight[BZ_MAX_ALPHA_SIZE * 2];
int32_t BZ2_hbMakeCodeLengths__parent[BZ_MAX_ALPHA_SIZE * 2];
int32_t mainSort__runningOrder[256];
int32_t mainSort__copyStart[256];
int32_t mainSort__copyEnd[256];
} EState;
/*-- compression. --*/
static void
BZ2_blockSort(EState*);
static void
BZ2_compressBlock(EState*, int);
static void
BZ2_bsInitWrite(EState*);
static void
BZ2_hbAssignCodes(int32_t*, uint8_t*, int32_t, int32_t, int32_t);
static void
BZ2_hbMakeCodeLengths(EState*, uint8_t*, int32_t*, int32_t, int32_t);
/*-------------------------------------------------------------*/
/*--- end bzlib_private.h ---*/
/*-------------------------------------------------------------*/