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Diffstat (limited to 'archival/bz/bzlib_private.h')
| -rw-r--r-- | archival/bz/bzlib_private.h | 234 |
1 files changed, 234 insertions, 0 deletions
diff --git a/archival/bz/bzlib_private.h b/archival/bz/bzlib_private.h new file mode 100644 index 0000000..24ffbee --- /dev/null +++ b/archival/bz/bzlib_private.h @@ -0,0 +1,234 @@ +/* + * 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" */ + +#define BZ_DEBUG 0 +//#define BZ_NO_STDIO 1 - does not work + + +/*-- General stuff. --*/ + +typedef unsigned char Bool; +typedef unsigned char UChar; + +#define True ((Bool)1) +#define False ((Bool)0) + +static void bz_assert_fail(int errcode) ATTRIBUTE_NORETURN; +#define AssertH(cond, errcode) \ +{ \ + if (!(cond)) \ + bz_assert_fail(errcode); \ +} + +#if BZ_DEBUG +#define AssertD(cond, msg) \ +{ \ + if (!(cond)) \ + bb_error_msg_and_die("(debug build): internal error %s", msg); \ +} +#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 randomising repetitive blocks. --*/ + +static const int32_t BZ2_rNums[512]; + +#define BZ_RAND_DECLS \ + int32_t rNToGo; \ + int32_t rTPos \ + +#define BZ_RAND_INIT_MASK \ + s->rNToGo = 0; \ + s->rTPos = 0 \ + +#define BZ_RAND_MASK ((s->rNToGo == 1) ? 1 : 0) + +#define BZ_RAND_UPD_MASK \ +{ \ + if (s->rNToGo == 0) { \ + s->rNToGo = BZ2_rNums[s->rTPos]; \ + s->rTPos++; \ + if (s->rTPos == 512) s->rTPos = 0; \ + } \ + s->rNToGo--; \ +} + + +/*-- Stuff for doing CRCs. --*/ + +static const uint32_t BZ2_crc32Table[256]; + +#define BZ_INITIALISE_CRC(crcVar) \ +{ \ + crcVar = 0xffffffffL; \ +} + +#define BZ_FINALISE_CRC(crcVar) \ +{ \ + crcVar = ~(crcVar); \ +} + +#define BZ_UPDATE_CRC(crcVar,cha) \ +{ \ + crcVar = (crcVar << 8) ^ BZ2_crc32Table[(crcVar >> 24) ^ ((UChar)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 */ + uint32_t avail_in_expect; //vda: do we need this? + + /* for doing the block sorting */ + uint32_t *arr1; + uint32_t *arr2; + uint32_t *ftab; + int32_t origPtr; + + /* aliases for arr1 and arr2 */ + uint32_t *ptr; + UChar *block; + uint16_t *mtfv; + UChar *zbits; + + /* run-length-encoding of the input */ + uint32_t state_in_ch; + int32_t state_in_len; + BZ_RAND_DECLS; + + /* 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]; + UChar unseqToSeq[256]; + + /* stuff for coding the MTF values */ + int32_t mtfFreq [BZ_MAX_ALPHA_SIZE]; + UChar selector [BZ_MAX_SELECTORS]; + UChar selectorMtf[BZ_MAX_SELECTORS]; + + UChar len [BZ_N_GROUPS][BZ_MAX_ALPHA_SIZE]; + int32_t code [BZ_N_GROUPS][BZ_MAX_ALPHA_SIZE]; + int32_t rfreq [BZ_N_GROUPS][BZ_MAX_ALPHA_SIZE]; +#ifdef FAST_GROUP6 + /* second dimension: only 3 needed; 4 makes index calculations faster */ + uint32_t len_pack[BZ_MAX_ALPHA_SIZE][4]; +#endif +} EState; + + +/*-- compression. --*/ + +static void +BZ2_blockSort(EState*); + +static void +BZ2_compressBlock(EState*, Bool); + +static void +BZ2_bsInitWrite(EState*); + +static void +BZ2_hbAssignCodes(int32_t*, UChar*, int32_t, int32_t, int32_t); + +static void +BZ2_hbMakeCodeLengths(UChar*, int32_t*, int32_t, int32_t); + +/*-------------------------------------------------------------*/ +/*--- end bzlib_private.h ---*/ +/*-------------------------------------------------------------*/ |