220 lines
5.2 KiB
C
220 lines
5.2 KiB
C
/*
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* bzip2 is written by Julian Seward <jseward@bzip.org>.
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* Adapted for busybox by Denys Vlasenko <vda.linux@googlemail.com>.
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* See README and LICENSE files in this directory for more information.
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*/
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/*-------------------------------------------------------------*/
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/*--- Private header file for the library. ---*/
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/*--- bzlib_private.h ---*/
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/*-------------------------------------------------------------*/
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/* ------------------------------------------------------------------
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This file is part of bzip2/libbzip2, a program and library for
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lossless, block-sorting data compression.
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bzip2/libbzip2 version 1.0.4 of 20 December 2006
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Copyright (C) 1996-2006 Julian Seward <jseward@bzip.org>
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Please read the WARNING, DISCLAIMER and PATENTS sections in the
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README file.
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This program is released under the terms of the license contained
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in the file LICENSE.
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------------------------------------------------------------------ */
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/* #include "bzlib.h" */
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/*-- General stuff. --*/
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typedef unsigned char Bool;
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#define True ((Bool)1)
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#define False ((Bool)0)
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#if BZ_LIGHT_DEBUG
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static void bz_assert_fail(int errcode) NORETURN;
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#define AssertH(cond, errcode) \
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do { \
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if (!(cond)) \
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bz_assert_fail(errcode); \
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} while (0)
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#else
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#define AssertH(cond, msg) do { } while (0)
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#endif
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#if BZ_DEBUG
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#define AssertD(cond, msg) \
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do { \
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if (!(cond)) \
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bb_error_msg_and_die("(debug build): internal error %s", msg); \
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} while (0)
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#else
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#define AssertD(cond, msg) do { } while (0)
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#endif
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/*-- Header bytes. --*/
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#define BZ_HDR_B 0x42 /* 'B' */
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#define BZ_HDR_Z 0x5a /* 'Z' */
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#define BZ_HDR_h 0x68 /* 'h' */
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#define BZ_HDR_0 0x30 /* '0' */
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#define BZ_HDR_BZh0 0x425a6830
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/*-- Constants for the back end. --*/
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#define BZ_MAX_ALPHA_SIZE 258
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#define BZ_MAX_CODE_LEN 23
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#define BZ_RUNA 0
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#define BZ_RUNB 1
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#define BZ_N_GROUPS 6
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#define BZ_G_SIZE 50
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#define BZ_N_ITERS 4
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#define BZ_MAX_SELECTORS (2 + (900000 / BZ_G_SIZE))
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/*-- Stuff for doing CRCs. --*/
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#define BZ_INITIALISE_CRC(crcVar) \
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{ \
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crcVar = 0xffffffffL; \
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}
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#define BZ_FINALISE_CRC(crcVar) \
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{ \
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crcVar = ~(crcVar); \
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}
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#define BZ_UPDATE_CRC(s, crcVar, cha) \
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{ \
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crcVar = (crcVar << 8) ^ s->crc32table[(crcVar >> 24) ^ ((uint8_t)cha)]; \
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}
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/*-- States and modes for compression. --*/
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#define BZ_M_IDLE 1
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#define BZ_M_RUNNING 2
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#define BZ_M_FLUSHING 3
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#define BZ_M_FINISHING 4
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#define BZ_S_OUTPUT 1
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#define BZ_S_INPUT 2
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#define BZ_N_RADIX 2
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#define BZ_N_QSORT 12
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#define BZ_N_SHELL 18
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#define BZ_N_OVERSHOOT (BZ_N_RADIX + BZ_N_QSORT + BZ_N_SHELL + 2)
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/*-- Structure holding all the compression-side stuff. --*/
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typedef struct EState {
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/* pointer back to the struct bz_stream */
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bz_stream *strm;
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/* mode this stream is in, and whether inputting */
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/* or outputting data */
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int32_t mode;
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int32_t state;
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/* remembers avail_in when flush/finish requested */
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/* bbox: not needed, strm->avail_in always has the same value */
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/* commented out with '//#' throughout the code */
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/* uint32_t avail_in_expect; */
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/* for doing the block sorting */
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int32_t origPtr;
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uint32_t *arr1;
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uint32_t *arr2;
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uint32_t *ftab;
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/* aliases for arr1 and arr2 */
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uint32_t *ptr;
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uint8_t *block;
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uint16_t *mtfv;
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uint8_t *zbits;
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/* guess what */
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uint32_t *crc32table;
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/* run-length-encoding of the input */
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uint32_t state_in_ch;
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int32_t state_in_len;
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/* input and output limits and current posns */
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int32_t nblock;
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int32_t nblockMAX;
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int32_t numZ;
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int32_t state_out_pos;
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/* the buffer for bit stream creation */
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uint32_t bsBuff;
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int32_t bsLive;
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/* block and combined CRCs */
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uint32_t blockCRC;
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uint32_t combinedCRC;
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/* misc administratium */
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int32_t blockNo;
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int32_t blockSize100k;
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/* stuff for coding the MTF values */
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int32_t nMTF;
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/* map of bytes used in block */
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int32_t nInUse;
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Bool inUse[256] ALIGNED(sizeof(long));
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uint8_t unseqToSeq[256];
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/* stuff for coding the MTF values */
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int32_t mtfFreq [BZ_MAX_ALPHA_SIZE];
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uint8_t selector [BZ_MAX_SELECTORS];
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uint8_t selectorMtf[BZ_MAX_SELECTORS];
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uint8_t len[BZ_N_GROUPS][BZ_MAX_ALPHA_SIZE];
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/* stack-saving measures: these can be local, but they are too big */
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int32_t sendMTFValues__code [BZ_N_GROUPS][BZ_MAX_ALPHA_SIZE];
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int32_t sendMTFValues__rfreq[BZ_N_GROUPS][BZ_MAX_ALPHA_SIZE];
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#if CONFIG_BZIP2_FAST >= 5
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/* second dimension: only 3 needed; 4 makes index calculations faster */
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uint32_t sendMTFValues__len_pack[BZ_MAX_ALPHA_SIZE][4];
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#endif
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int32_t BZ2_hbMakeCodeLengths__heap [BZ_MAX_ALPHA_SIZE + 2];
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int32_t BZ2_hbMakeCodeLengths__weight[BZ_MAX_ALPHA_SIZE * 2];
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int32_t BZ2_hbMakeCodeLengths__parent[BZ_MAX_ALPHA_SIZE * 2];
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int32_t mainSort__runningOrder[256];
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int32_t mainSort__copyStart[256];
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int32_t mainSort__copyEnd[256];
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} EState;
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/*-- compression. --*/
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static void
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BZ2_blockSort(EState*);
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static void
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BZ2_compressBlock(EState*, int);
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static void
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BZ2_bsInitWrite(EState*);
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static void
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BZ2_hbAssignCodes(int32_t*, uint8_t*, int32_t, int32_t, int32_t);
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static void
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BZ2_hbMakeCodeLengths(EState*, uint8_t*, int32_t*, int32_t, int32_t);
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/*-------------------------------------------------------------*/
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/*--- end bzlib_private.h ---*/
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/*-------------------------------------------------------------*/
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