diff options
| -rw-r--r-- | archival/libunarchive/decompress_bunzip2.c | 2057 |
1 files changed, 465 insertions, 1592 deletions
diff --git a/archival/libunarchive/decompress_bunzip2.c b/archival/libunarchive/decompress_bunzip2.c index 0164b77..474186a 100644 --- a/archival/libunarchive/decompress_bunzip2.c +++ b/archival/libunarchive/decompress_bunzip2.c @@ -1,1658 +1,531 @@ -/*-- - This file is a part of bzip2 and/or libbzip2, a program and - library for lossless, block-sorting data compression. +/* vi: set sw=4 ts=4: */ +/* Small bzip2 deflate implementation, by Rob Landley (rob@landley.net). - Copyright (C) 1996-2000 Julian R Seward. All rights reserved. + Based on bzip2 decompression code by Julian R Seward (jseward@acm.org), + which also acknowledges contributions by Mike Burrows, David Wheeler, + Peter Fenwick, Alistair Moffat, Radford Neal, Ian H. Witten, + Robert Sedgewick, and Jon L. Bentley. - Redistribution and use in source and binary forms, with or without - modification, are permitted provided that the following conditions - are met: + This code is licensed under the LGPLv2: + LGPL (http://www.gnu.org/copyleft/lgpl.html +*/ - 1. Redistributions of source code must retain the above copyright - notice, this list of conditions and the following disclaimer. - - 2. The origin of this software must not be misrepresented; you must - not claim that you wrote the original software. If you use this - software in a product, an acknowledgment in the product - documentation would be appreciated but is not required. - - 3. Altered source versions must be plainly marked as such, and must - not be misrepresented as being the original software. - - 4. The name of the author may not be used to endorse or promote - products derived from this software without specific prior written - permission. - - THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS - OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED - WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE - ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY - DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL - DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE - GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS - INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, - WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING - NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS - SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. - - Julian Seward, Cambridge, UK. - jseward@acm.org - bzip2/libbzip2 version 1.0 of 21 March 2000 - - This program is based on (at least) the work of: - Mike Burrows - David Wheeler - Peter Fenwick - Alistair Moffat - Radford Neal - Ian H. Witten - Robert Sedgewick - Jon L. Bentley - - For more information on these sources, see the manual. ---*/ - -#include <stdlib.h> +#include <setjmp.h> #include <stdio.h> +#include <stdlib.h> #include <string.h> -#include <getopt.h> #include <unistd.h> -#include "busybox.h" - -#define MTFA_SIZE 4096 -#define MTFL_SIZE 16 -#define BZ_N_GROUPS 6 -#define BZ_G_SIZE 50 -#define BZ_MAX_ALPHA_SIZE 258 - -#define BZ_OK 0 -#define BZ_STREAM_END 4 -#define BZ_SEQUENCE_ERROR (-1) -#define BZ_DATA_ERROR (-4) -#define BZ_DATA_ERROR_MAGIC (-5) -#define BZ_IO_ERROR (-6) -#define BZ_UNEXPECTED_EOF (-7) - -#define BZ_RUNA 0 -#define BZ_RUNB 1 - -#define BZ_MAX_UNUSED 5000 -#define FILE_NAME_LEN 1034 -/*-- states for decompression. --*/ - -#define BZ_X_IDLE 1 -#define BZ_X_OUTPUT 2 - -#define BZ_X_MAGIC_1 10 -#define BZ_X_MAGIC_2 11 -#define BZ_X_MAGIC_3 12 -#define BZ_X_MAGIC_4 13 -#define BZ_X_BLKHDR_1 14 -#define BZ_X_BLKHDR_2 15 -#define BZ_X_BLKHDR_3 16 -#define BZ_X_BLKHDR_4 17 -#define BZ_X_BLKHDR_5 18 -#define BZ_X_BLKHDR_6 19 -#define BZ_X_BCRC_1 20 -#define BZ_X_BCRC_2 21 -#define BZ_X_BCRC_3 22 -#define BZ_X_BCRC_4 23 -#define BZ_X_RANDBIT 24 -#define BZ_X_ORIGPTR_1 25 -#define BZ_X_ORIGPTR_2 26 -#define BZ_X_ORIGPTR_3 27 -#define BZ_X_MAPPING_1 28 -#define BZ_X_MAPPING_2 29 -#define BZ_X_SELECTOR_1 30 -#define BZ_X_SELECTOR_2 31 -#define BZ_X_SELECTOR_3 32 -#define BZ_X_CODING_1 33 -#define BZ_X_CODING_2 34 -#define BZ_X_CODING_3 35 -#define BZ_X_MTF_1 36 -#define BZ_X_MTF_2 37 -#define BZ_X_MTF_3 38 -#define BZ_X_MTF_4 39 -#define BZ_X_MTF_5 40 -#define BZ_X_MTF_6 41 -#define BZ_X_ENDHDR_2 42 -#define BZ_X_ENDHDR_3 43 -#define BZ_X_ENDHDR_4 44 -#define BZ_X_ENDHDR_5 45 -#define BZ_X_ENDHDR_6 46 -#define BZ_X_CCRC_1 47 -#define BZ_X_CCRC_2 48 -#define BZ_X_CCRC_3 49 -#define BZ_X_CCRC_4 50 - -#define BZ_MAX_CODE_LEN 23 -#define OM_TEST 3 - -typedef struct { - char *next_in; - unsigned int avail_in; - - char *next_out; - unsigned int avail_out; - - void *state; - -} bz_stream; - -#define BZ_MAX_UNUSED 5000 -typedef struct { - bz_stream strm; - int fd; - unsigned char initialisedOk; - char buf[BZ_MAX_UNUSED]; - int lastErr; - int bufN; -} bzFile; - -/*-- Structure holding all the decompression-side stuff. --*/ -typedef struct { - /* pointer back to the struct bz_stream */ - bz_stream* strm; - - /* state indicator for this stream */ - int state; - - /* for doing the final run-length decoding */ - unsigned char state_out_ch; - int state_out_len; - unsigned char blockRandomised; - int rNToGo; - int rTPos; - - /* the buffer for bit stream reading */ - unsigned int bsBuff; - int bsLive; - - /* misc administratium */ - int blockSize100k; - int currBlockNo; - - /* for undoing the Burrows-Wheeler transform */ - int origPtr; - unsigned int tPos; - int k0; - int unzftab[256]; - int nblock_used; - int cftab[257]; - int cftabCopy[257]; - - /* for undoing the Burrows-Wheeler transform (FAST) */ - unsigned int *tt; - - /* stored and calculated CRCs */ - unsigned int storedBlockCRC; - unsigned int storedCombinedCRC; - unsigned int calculatedBlockCRC; - unsigned int calculatedCombinedCRC; - - /* map of bytes used in block */ - int nInUse; - unsigned char inUse[256]; - unsigned char inUse16[16]; - unsigned char seqToUnseq[256]; - - /* for decoding the MTF values */ - unsigned char mtfa [MTFA_SIZE]; - unsigned char selector [2 + (900000 / BZ_G_SIZE)]; - unsigned char selectorMtf[2 + (900000 / BZ_G_SIZE)]; - unsigned char len [BZ_N_GROUPS][BZ_MAX_ALPHA_SIZE]; - int mtfbase[256 / MTFL_SIZE]; - - int limit [BZ_N_GROUPS][BZ_MAX_ALPHA_SIZE]; - int base [BZ_N_GROUPS][BZ_MAX_ALPHA_SIZE]; - int perm [BZ_N_GROUPS][BZ_MAX_ALPHA_SIZE]; - int minLens[BZ_N_GROUPS]; - - /* save area for scalars in the main decompress code */ - int save_i; - int save_j; - int save_t; - int save_alphaSize; - int save_nGroups; - int save_nSelectors; - int save_EOB; - int save_groupNo; - int save_groupPos; - int save_nextSym; - int save_nblockMAX; - int save_nblock; - int save_es; - int save_N; - int save_curr; - int save_zt; - int save_zn; - int save_zvec; - int save_zj; - int save_gSel; - int save_gMinlen; - int *save_gLimit; - int *save_gBase; - int *save_gPerm; -} DState; - -static int BZ2_rNums[512]; -static bzFile *bzf; -static int bzerr = BZ_OK; - -static const unsigned int BZ2_crc32Table[256] = { - - /*-- Ugly, innit? --*/ - - 0x00000000L, 0x04c11db7L, 0x09823b6eL, 0x0d4326d9L, - 0x130476dcL, 0x17c56b6bL, 0x1a864db2L, 0x1e475005L, - 0x2608edb8L, 0x22c9f00fL, 0x2f8ad6d6L, 0x2b4bcb61L, - 0x350c9b64L, 0x31cd86d3L, 0x3c8ea00aL, 0x384fbdbdL, - 0x4c11db70L, 0x48d0c6c7L, 0x4593e01eL, 0x4152fda9L, - 0x5f15adacL, 0x5bd4b01bL, 0x569796c2L, 0x52568b75L, - 0x6a1936c8L, 0x6ed82b7fL, 0x639b0da6L, 0x675a1011L, - 0x791d4014L, 0x7ddc5da3L, 0x709f7b7aL, 0x745e66cdL, - 0x9823b6e0L, 0x9ce2ab57L, 0x91a18d8eL, 0x95609039L, - 0x8b27c03cL, 0x8fe6dd8bL, 0x82a5fb52L, 0x8664e6e5L, - 0xbe2b5b58L, 0xbaea46efL, 0xb7a96036L, 0xb3687d81L, - 0xad2f2d84L, 0xa9ee3033L, 0xa4ad16eaL, 0xa06c0b5dL, - 0xd4326d90L, 0xd0f37027L, 0xddb056feL, 0xd9714b49L, - 0xc7361b4cL, 0xc3f706fbL, 0xceb42022L, 0xca753d95L, - 0xf23a8028L, 0xf6fb9d9fL, 0xfbb8bb46L, 0xff79a6f1L, - 0xe13ef6f4L, 0xe5ffeb43L, 0xe8bccd9aL, 0xec7dd02dL, - 0x34867077L, 0x30476dc0L, 0x3d044b19L, 0x39c556aeL, - 0x278206abL, 0x23431b1cL, 0x2e003dc5L, 0x2ac12072L, - 0x128e9dcfL, 0x164f8078L, 0x1b0ca6a1L, 0x1fcdbb16L, - 0x018aeb13L, 0x054bf6a4L, 0x0808d07dL, 0x0cc9cdcaL, - 0x7897ab07L, 0x7c56b6b0L, 0x71159069L, 0x75d48ddeL, - 0x6b93dddbL, 0x6f52c06cL, 0x6211e6b5L, 0x66d0fb02L, - 0x5e9f46bfL, 0x5a5e5b08L, 0x571d7dd1L, 0x53dc6066L, - 0x4d9b3063L, 0x495a2dd4L, 0x44190b0dL, 0x40d816baL, - 0xaca5c697L, 0xa864db20L, 0xa527fdf9L, 0xa1e6e04eL, - 0xbfa1b04bL, 0xbb60adfcL, 0xb6238b25L, 0xb2e29692L, - 0x8aad2b2fL, 0x8e6c3698L, 0x832f1041L, 0x87ee0df6L, - 0x99a95df3L, 0x9d684044L, 0x902b669dL, 0x94ea7b2aL, - 0xe0b41de7L, 0xe4750050L, 0xe9362689L, 0xedf73b3eL, - 0xf3b06b3bL, 0xf771768cL, 0xfa325055L, 0xfef34de2L, - 0xc6bcf05fL, 0xc27dede8L, 0xcf3ecb31L, 0xcbffd686L, - 0xd5b88683L, 0xd1799b34L, 0xdc3abdedL, 0xd8fba05aL, - 0x690ce0eeL, 0x6dcdfd59L, 0x608edb80L, 0x644fc637L, - 0x7a089632L, 0x7ec98b85L, 0x738aad5cL, 0x774bb0ebL, - 0x4f040d56L, 0x4bc510e1L, 0x46863638L, 0x42472b8fL, - 0x5c007b8aL, 0x58c1663dL, 0x558240e4L, 0x51435d53L, - 0x251d3b9eL, 0x21dc2629L, 0x2c9f00f0L, 0x285e1d47L, - 0x36194d42L, 0x32d850f5L, 0x3f9b762cL, 0x3b5a6b9bL, - 0x0315d626L, 0x07d4cb91L, 0x0a97ed48L, 0x0e56f0ffL, - 0x1011a0faL, 0x14d0bd4dL, 0x19939b94L, 0x1d528623L, - 0xf12f560eL, 0xf5ee4bb9L, 0xf8ad6d60L, 0xfc6c70d7L, - 0xe22b20d2L, 0xe6ea3d65L, 0xeba91bbcL, 0xef68060bL, - 0xd727bbb6L, 0xd3e6a601L, 0xdea580d8L, 0xda649d6fL, - 0xc423cd6aL, 0xc0e2d0ddL, 0xcda1f604L, 0xc960ebb3L, - 0xbd3e8d7eL, 0xb9ff90c9L, 0xb4bcb610L, 0xb07daba7L, - 0xae3afba2L, 0xaafbe615L, 0xa7b8c0ccL, 0xa379dd7bL, - 0x9b3660c6L, 0x9ff77d71L, 0x92b45ba8L, 0x9675461fL, - 0x8832161aL, 0x8cf30badL, 0x81b02d74L, 0x857130c3L, - 0x5d8a9099L, 0x594b8d2eL, 0x5408abf7L, 0x50c9b640L, - 0x4e8ee645L, 0x4a4ffbf2L, 0x470cdd2bL, 0x43cdc09cL, - 0x7b827d21L, 0x7f436096L, 0x7200464fL, 0x76c15bf8L, - 0x68860bfdL, 0x6c47164aL, 0x61043093L, 0x65c52d24L, - 0x119b4be9L, 0x155a565eL, 0x18197087L, 0x1cd86d30L, - 0x029f3d35L, 0x065e2082L, 0x0b1d065bL, 0x0fdc1becL, - 0x3793a651L, 0x3352bbe6L, 0x3e119d3fL, 0x3ad08088L, - 0x2497d08dL, 0x2056cd3aL, 0x2d15ebe3L, 0x29d4f654L, - 0xc5a92679L, 0xc1683bceL, 0xcc2b1d17L, 0xc8ea00a0L, - 0xd6ad50a5L, 0xd26c4d12L, 0xdf2f6bcbL, 0xdbee767cL, - 0xe3a1cbc1L, 0xe760d676L, 0xea23f0afL, 0xeee2ed18L, - 0xf0a5bd1dL, 0xf464a0aaL, 0xf9278673L, 0xfde69bc4L, - 0x89b8fd09L, 0x8d79e0beL, 0x803ac667L, 0x84fbdbd0L, - 0x9abc8bd5L, 0x9e7d9662L, 0x933eb0bbL, 0x97ffad0cL, - 0xafb010b1L, 0xab710d06L, 0xa6322bdfL, 0xa2f33668L, - 0xbcb4666dL, 0xb8757bdaL, 0xb5365d03L, 0xb1f740b4L +/* 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 + +char *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."}; + +/* This is what we know about each huffman coding group */ +struct group_data { + int limit[MAX_HUFCODE_BITS],base[MAX_HUFCODE_BITS],permute[MAX_SYMBOLS]; + char minLen, maxLen; }; -static void bz_rand_udp_mask(DState *s) +/* Structure holding all the housekeeping data, including IO buffers and + memory that persists between calls to bunzip */ +typedef struct { + /* For I/O error handling */ + jmp_buf jmpbuf; + /* Input stream, input buffer, input bit buffer */ + int in_fd,inbufCount,inbufPos; + unsigned char *inbuf; + unsigned int inbufBitCount, inbufBits; + /* Output buffer */ + char outbuf[IOBUF_SIZE]; + int outbufPos; + /* The CRC values stored in the block header and calculated from the data */ + unsigned int crc32Table[256],headerCRC, dataCRC, totalCRC; + /* Intermediate buffer and its size (in bytes) */ + unsigned int *dbuf, dbufSize; + /* State for interrupting output loop */ + int writePos,writeRun,writeCount,writeCurrent; + + /* 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 */ +} bunzip_data; + +/* Return the next nnn bits of input. All reads from the compressed input + are done through this function. All reads are big endian */ +static unsigned int get_bits(bunzip_data *bd, char bits_wanted) { - if (s->rNToGo == 0) { - s->rNToGo = BZ2_rNums[s->rTPos]; - s->rTPos++; - if (s->rTPos == 512) { - s->rTPos = 0; + unsigned int bits=0; + + /* If we need to get more data from the byte buffer, do so. (Loop getting + one byte at a time to enforce endianness and avoid unaligned access.) */ + while (bd->inbufBitCount<bits_wanted) { + /* If we need to read more data from file into byte buffer, do so */ + if(bd->inbufPos==bd->inbufCount) { + if(!(bd->inbufCount = read(bd->in_fd, bd->inbuf, IOBUF_SIZE))) + longjmp(bd->jmpbuf,RETVAL_UNEXPECTED_INPUT_EOF); + bd->inbufPos=0; } - } - s->rNToGo--; -} - -static void BZ2_hbCreateDecodeTables(int *limit, int *base, int *perm, unsigned char *length, int minLen, int maxLen, int alphaSize ) -{ - int pp, i, j, vec; - - pp = 0; - for (i = minLen; i <= maxLen; i++) { - for (j = 0; j < alphaSize; j++) { - if (length[j] == i) { - perm[pp] = j; - pp++; - } + /* Avoid 32-bit overflow (dump bit buffer to top of output) */ + if(bd->inbufBitCount>=24) { + bits=bd->inbufBits&((1<<bd->inbufBitCount)-1); + bits_wanted-=bd->inbufBitCount; + bits<<=bits_wanted; + bd->inbufBitCount=0; } + /* Grab next 8 bits of input from buffer. */ + bd->inbufBits=(bd->inbufBits<<8)|bd->inbuf[bd->inbufPos++]; + bd->inbufBitCount+=8; } + /* Calculate result */ + bd->inbufBitCount-=bits_wanted; + bits|=(bd->inbufBits>>bd->inbufBitCount)&((1<<bits_wanted)-1); - for (i = 0; i < BZ_MAX_CODE_LEN; i++) { - base[i] = 0; - } - - for (i = 0; i < alphaSize; i++) { - base[length[i]+1]++; - } - - for (i = 1; i < BZ_MAX_CODE_LEN; i++) { - base[i] += base[i-1]; - } - - for (i = 0; i < BZ_MAX_CODE_LEN; i++) { - limit[i] = 0; - } - vec = 0; - - for (i = minLen; i <= maxLen; i++) { - vec += (base[i+1] - base[i]); - limit[i] = vec-1; - vec <<= 1; - } - for (i = minLen + 1; i <= maxLen; i++) { - base[i] = ((limit[i-1] + 1) << 1) - base[i]; - } -} - - -static int get_bits(DState *s, int *vvv, char nnn) -{ - while (1) { - if (s->bsLive >= nnn) { - *vvv = (s->bsBuff >> (s->bsLive-nnn)) & ((1 << nnn)-1); - s->bsLive -= nnn; - break; - } - if (s->strm->avail_in == 0) { - return(FALSE); - } - s->bsBuff = (s->bsBuff << 8) | ((unsigned int) (*((unsigned char*)(s->strm->next_in)))); - s->bsLive += 8; - s->strm->next_in++; - s->strm->avail_in--; - } - return(TRUE); + return bits; } -static int bz_get_fast(DState *s) -{ - int cccc; - s->tPos = s->tt[s->tPos]; - cccc = (unsigned char)(s->tPos & 0xff); - s->tPos >>= 8; - return(cccc); -} +/* Decompress a block of text to into intermediate buffer */ -/*---------------------------------------------------*/ -static inline int BZ2_decompress(DState *s) +extern int read_bunzip_data(bunzip_data *bd) { - int uc = 0; - int retVal; - int minLen, maxLen; - - /* stuff that needs to be saved/restored */ - int i; - int j; - int t; - int alphaSize; - int nGroups; - int nSelectors; - int EOB; - int groupNo; - int groupPos; - int nextSym; - int nblockMAX; - int nblock; - int es; - int N; - int curr; - int zt; - int zn; - int zvec; - int zj; - int gSel; - int gMinlen; - int *gLimit; - int *gBase; - int *gPerm; - int switch_val; - - int get_mtf_val_init(void) - { - if (groupPos == 0) { - groupNo++; - if (groupNo >= nSelectors) { - retVal = BZ_DATA_ERROR; - return(FALSE); - } - groupPos = BZ_G_SIZE; - gSel = s->selector[groupNo]; - gMinlen = s->minLens[gSel]; - gLimit = &(s->limit[gSel][0]); - gPerm = &(s->perm[gSel][0]); - gBase = &(s->base[gSel][0]); + struct group_data *hufGroup; + int dbufCount,nextSym,dbufSize,origPtr,groupCount,*base,*limit,selector, + i,j,k,t,runPos,symCount,symTotal,nSelectors,byteCount[256]; + unsigned char uc, symToByte[256], mtfSymbol[256], *selectors; + unsigned int *dbuf; + + /* Read in header signature (borrowing mtfSymbol for temp space). */ + for(i=0;i<6;i++) mtfSymbol[i]=get_bits(bd,8); + mtfSymbol[6]=0; + /* Read CRC (which is stored big endian). */ + bd->headerCRC=get_bits(bd,32); + /* Is this the last block (with CRC for file)? */ + if(!strcmp(mtfSymbol,"\x17\x72\x45\x38\x50\x90")) + return RETVAL_LAST_BLOCK; + /* If it's not a valid data block, barf. */ + if(strcmp(mtfSymbol,"\x31\x41\x59\x26\x53\x59")) + return RETVAL_NOT_BZIP_DATA; + + dbuf=bd->dbuf; + dbufSize=bd->dbufSize; + selectors=bd->selectors; + /* We can add support for blockRandomised if anybody complains. There was + some code for this in busybox 1.0.0-pre3, but nobody ever noticed that + it didn't actually work. */ + if(get_bits(bd,1)) return RETVAL_OBSOLETE_INPUT; + if((origPtr=get_bits(bd,24)) > dbufSize) return RETVAL_DATA_ERROR; + /* mapping table: if some byte values are never used (encoding things + like ascii text), the compression code removes the gaps to have fewer + symbols to deal with, and writes a sparse bitfield indicating which + values were present. We make a translation table to convert the symbols + back to the corresponding bytes. */ + t=get_bits(bd, 16); + memset(symToByte,0,256); + symTotal=0; + for (i=0;i<16;i++) { + if(t&(1<<(15-i))) { + k=get_bits(bd,16); + for(j=0;j<16;j++) + if(k&(1<<(15-j))) symToByte[symTotal++]=(16*i)+j; } - groupPos--; - zn = gMinlen; - return(TRUE); } - - if (s->state == BZ_X_MAGIC_1) { - /*initialise the save area*/ - s->save_i = 0; - s->save_j = 0; - s->save_t = 0; - s->save_alphaSize = 0; - s->save_nGroups = 0; - s->save_nSelectors = 0; - s->save_EOB = 0; - s->save_groupNo = 0; - s->save_groupPos = 0; - s->save_nextSym = 0; - s->save_nblockMAX = 0; - s->save_nblock = 0; - s->save_es = 0; - s->save_N = 0; - s->save_curr = 0; - s->save_zt = 0; - s->save_zn = 0; - s->save_zvec = 0; - s->save_zj = 0; - s->save_gSel = 0; - s->save_gMinlen = 0; - s->save_gLimit = NULL; - s->save_gBase = NULL; - s->save_gPerm = NULL; + /* How many different huffman coding groups does this block use? */ + groupCount=get_bits(bd,3); + if (groupCount<2 || groupCount>MAX_GROUPS) return RETVAL_DATA_ERROR; + /* nSelectors: Every GROUP_SIZE many symbols we select a new huffman coding + group. Read in the group selector list, which is stored as MTF encoded + bit runs. */ + if(!(nSelectors=get_bits(bd, 15))) return RETVAL_DATA_ERROR; + for(i=0; i<groupCount; i++) mtfSymbol[i] = i; + for(i=0; i<nSelectors; i++) { + /* Get next value */ + for(j=0;get_bits(bd,1);j++) if (j>=groupCount) return RETVAL_DATA_ERROR; + /* Decode MTF to get the next selector */ + uc = mtfSymbol[j]; + memmove(mtfSymbol+1,mtfSymbol,j); + mtfSymbol[0]=selectors[i]=uc; } - - /*restore from the save area*/ - i = s->save_i; - j = s->save_j; - t = s->save_t; - alphaSize = s->save_alphaSize; - nGroups = s->save_nGroups; - nSelectors = s->save_nSelectors; - EOB = s->save_EOB; - groupNo = s->save_groupNo; - groupPos = s->save_groupPos; - nextSym = s->save_nextSym; - nblockMAX = s->save_nblockMAX; - nblock = s->save_nblock; - es = s->save_es; - N = s->save_N; - curr = s->save_curr; - zt = s->save_zt; - zn = s->save_zn; - zvec = s->save_zvec; - zj = s->save_zj; - gSel = s->save_gSel; - gMinlen = s->save_gMinlen; - gLimit = s->save_gLimit; - gBase = s->save_gBase; - gPerm = s->save_gPerm; - - retVal = BZ_OK; - switch_val = s->state; - switch (switch_val) { - case BZ_X_MAGIC_1: - s->state = BZ_X_MAGIC_1; - if (! get_bits(s, &uc, 8)) { - retVal = BZ_OK; - goto save_state_and_return; - } - if (uc != 'B') { - retVal = BZ_DATA_ERROR_MAGIC; - goto save_state_and_return; - } - - case BZ_X_MAGIC_2: - s->state = BZ_X_MAGIC_2; - if (! get_bits(s, &uc, 8)) { - retVal = BZ_OK; - goto save_state_and_return; - } - if (uc != 'Z') { - retVal = BZ_DATA_ERROR_MAGIC; - goto save_state_and_return; - } - - case BZ_X_MAGIC_3: - s->state = BZ_X_MAGIC_3; - if (! get_bits(s, &uc, 8)) { - retVal = BZ_OK; - goto save_state_and_return; - } - if (uc != 'h') { - retVal = BZ_DATA_ERROR_MAGIC; - goto save_state_and_return; - } - - case BZ_X_MAGIC_4: - s->state = BZ_X_MAGIC_4; - if (! get_bits(s, &s->blockSize100k, 8)) { - retVal = BZ_OK; - goto save_state_and_return; - } - if ((s->blockSize100k < '1') || (s->blockSize100k > '9')) { - retVal = BZ_DATA_ERROR_MAGIC; - goto save_state_and_return; - } - s->blockSize100k -= '0'; - - s->tt = xmalloc(s->blockSize100k * 100000 * sizeof(int)); - - case BZ_X_BLKHDR_1: - s->state = BZ_X_BLKHDR_1; - if (! get_bits(s, &uc, 8)) { - retVal = BZ_OK; - goto save_state_and_return; - } - - if (uc == 0x17) { - goto endhdr_2; - } - if (uc != 0x31) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; - } - - case BZ_X_BLKHDR_2: - s->state = BZ_X_BLKHDR_2; - if (! get_bits(s, &uc, 8)) { - retVal = BZ_OK; - goto save_state_and_return; - } - if (uc != 0x41) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; - } - - case BZ_X_BLKHDR_3: - s->state = BZ_X_BLKHDR_3; - if (! get_bits(s, &uc, 8)) { - retVal = BZ_OK; - goto save_state_and_return; - } - if (uc != 0x59) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; - } - - case BZ_X_BLKHDR_4: - s->state = BZ_X_BLKHDR_4; - if (! get_bits(s, &uc, 8)) { - retVal = BZ_OK; - goto save_state_and_return; - } - if (uc != 0x26) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; - } - - case BZ_X_BLKHDR_5: - s->state = BZ_X_BLKHDR_5; - if (! get_bits(s, &uc, 8)) { - retVal = BZ_OK; - goto save_state_and_return; - } - if (uc != 0x53) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; - } - - case BZ_X_BLKHDR_6: - s->state = BZ_X_BLKHDR_6; - if (! get_bits(s, &uc, 8)) { - retVal = BZ_OK; - goto save_state_and_return; - } - if (uc != 0x59) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; - } - - s->currBlockNo++; - s->storedBlockCRC = 0; - - case BZ_X_BCRC_1: - s->state = BZ_X_BCRC_1; - if (! get_bits(s, &uc, 8)) { - retVal = BZ_OK; - goto save_state_and_return; - } - s->storedBlockCRC = (s->storedBlockCRC << 8) | ((unsigned int)uc); - - case BZ_X_BCRC_2: - s->state = BZ_X_BCRC_2; - if (! get_bits(s, &uc, 8)) { - retVal = BZ_OK; - goto save_state_and_return; - } - s->storedBlockCRC = (s->storedBlockCRC << 8) | ((unsigned int)uc); - - case BZ_X_BCRC_3: - s->state = BZ_X_BCRC_3; - if (! get_bits(s, &uc, 8)) { - retVal = BZ_OK; - goto save_state_and_return; - } - s->storedBlockCRC = (s->storedBlockCRC << 8) | ((unsigned int)uc); - - case BZ_X_BCRC_4: - s->state = BZ_X_BCRC_4; - if (! get_bits(s, &uc, 8)) { - retVal = BZ_OK; - goto save_state_and_return; - } - s->storedBlockCRC = (s->storedBlockCRC << 8) | ((unsigned int)uc); - - case BZ_X_RANDBIT: - s->state = BZ_X_RANDBIT; - { - int tmp = s->blockRandomised; - const int ret = get_bits(s, &tmp, 1); - s->blockRandomised = tmp; - if (! ret) { - retVal = BZ_OK; - goto save_state_and_return; - } - } - - s->origPtr = 0; - - case BZ_X_ORIGPTR_1: - s->state = BZ_X_ORIGPTR_1; - if (! get_bits(s, &uc, 8)) { - retVal = BZ_OK; - goto save_state_and_return; - } - s->origPtr = (s->origPtr << 8) | ((int)uc); - - case BZ_X_ORIGPTR_2: - s->state = BZ_X_ORIGPTR_2; - if (! get_bits(s, &uc, 8)) { - retVal = BZ_OK; - goto save_state_and_return; - } - s->origPtr = (s->origPtr << 8) | ((int)uc); - - case BZ_X_ORIGPTR_3: - s->state = BZ_X_ORIGPTR_3; - if (! get_bits(s, &uc, 8)) { - retVal = BZ_OK; - goto save_state_and_return; - } - s->origPtr = (s->origPtr << 8) | ((int)uc); - - if (s->origPtr < 0) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; - } - if (s->origPtr > 10 + 100000*s->blockSize100k) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; - } - - /*--- Receive the mapping table ---*/ - case BZ_X_MAPPING_1: - for (i = 0; i < 16; i++) { - s->state = BZ_X_MAPPING_1; - if (! get_bits(s, &uc, 1)) { - retVal = BZ_OK; - goto save_state_and_return; - } - if (uc == 1) { - s->inUse16[i] = TRUE; - } else { - s->inUse16[i] = FALSE; - } - } - - for (i = 0; i < 256; i++) { - s->inUse[i] = FALSE; - } - - for (i = 0; i < 16; i++) { - if (s->inUse16[i]) { - for (j = 0; j < 16; j++) { - case BZ_X_MAPPING_2: - s->state = BZ_X_MAPPING_2; - if (! get_bits(s, &uc, 1)) { - retVal = BZ_OK; - goto save_state_and_return; - } - if (uc == 1) { - s->inUse[i * 16 + j] = TRUE; - } - } - } - } - - s->nInUse = 0; - for (i = 0; i < 256; i++) { - if (s->inUse[i]) { - s->seqToUnseq[s->nInUse] = i; - s->nInUse++; - } - } - if (s->nInUse == 0) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; - } - alphaSize = s->nInUse+2; - - /*--- Now the selectors ---*/ - case BZ_X_SELECTOR_1: - s->state = BZ_X_SELECTOR_1; - if (! get_bits(s, &nGroups, 3)) { - retVal = BZ_OK; - goto save_state_and_return; - } - if (nGroups < 2 || nGroups > 6) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; - } - - case BZ_X_SELECTOR_2: - s->state = BZ_X_SELECTOR_2; - if (! get_bits(s, &nSelectors, 15)) { - retVal = BZ_OK; - goto save_state_and_return; - } - if (nSelectors < 1) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; - } - - - - for (i = 0; i < nSelectors; i++) { - j = 0; - while (1) { - case BZ_X_SELECTOR_3: - s->state = BZ_X_SELECTOR_3; - if (! get_bits(s, &uc, 1)) { - retVal = BZ_OK; - goto save_state_and_return; - } - if (uc == 0) { - break; - } - j++; - if (j >= nGroups) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; - } - } - s->selectorMtf[i] = j; - } - - /*--- Undo the MTF values for the selectors. ---*/ - { - unsigned char pos[BZ_N_GROUPS], tmp, v; - for (v = 0; v < nGroups; v++) { - pos[v] = v; - } - for (i = 0; i < nSelectors; i++) { - v = s->selectorMtf[i]; - tmp = pos[v]; - while (v > 0) { - pos[v] = pos[v-1]; - v--; - } - pos[0] = tmp; - s->selector[i] = tmp; - } - } - - /*--- Now the coding tables ---*/ - for (t = 0; t < nGroups; t++) { - case BZ_X_CODING_1: - s->state = BZ_X_CODING_1; - if (! get_bits(s, &curr, 5)) { - retVal = BZ_OK; - goto save_state_and_return; - } - for (i = 0; i < alphaSize; i++) { - while (TRUE) { - if (curr < 1 || curr > 20) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; - } - - case BZ_X_CODING_2: - s->state = BZ_X_CODING_2; - if (! get_bits(s, &uc, 1)) { - retVal = BZ_OK; - goto save_state_and_return; - } - if (uc == 0) { - break; - } - - case BZ_X_CODING_3: - s->state = BZ_X_CODING_3; - if (! get_bits(s, &uc, 1)) { - retVal = BZ_OK; - goto save_state_and_return; - } - if (uc == 0) { - curr++; - } else { - curr--; - } - } - s->len[t][i] = curr; - } + /* Read the huffman coding tables for each group, which code for symTotal + literal symbols, plus two run symbols (RUNA, RUNB) */ + symCount=symTotal+2; + for (j=0; j<groupCount; j++) { + unsigned char length[MAX_SYMBOLS],temp[MAX_HUFCODE_BITS+1]; + int minLen, maxLen, pp; + /* Read lengths */ + t=get_bits(bd, 5); + for (i = 0; i < symCount; i++) { + for(;;) { + if (t < 1 || t > MAX_HUFCODE_BITS) return RETVAL_DATA_ERROR; + if(!get_bits(bd, 1)) break; + if(!get_bits(bd, 1)) t++; + else t--; + } + length[i] = t; } - - /*--- Create the Huffman decoding tables ---*/ - for (t = 0; t < nGroups; t++) { - minLen = 32; - maxLen = 0; - for (i = 0; i < alphaSize; i++) { - if (s->len[t][i] > maxLen) { - maxLen = s->len[t][i]; - } - if (s->len[t][i] < minLen) { - minLen = s->len[t][i]; - } - } - - BZ2_hbCreateDecodeTables ( - &(s->limit[t][0]), - &(s->base[t][0]), - &(s->perm[t][0]), - &(s->len[t][0]), - minLen, maxLen, alphaSize - ); - - - s->minLens[t] = minLen; + /* Find largest and smallest lengths in this group */ + minLen=maxLen=length[0]; + for(i = 1; i < symCount; i++) { + if(length[i] > maxLen) maxLen = length[i]; + else if(length[i] < minLen) minLen = length[i]; } - - /*--- Now the MTF values ---*/ - - EOB = s->nInUse+1; - nblockMAX = 100000 * s->blockSize100k; - groupNo = -1; - groupPos = 0; - - for (i = 0; i <= 255; i++) { - s->unzftab[i] = 0; + /* Calculate permute[], base[], and limit[] tables from length[]. + * + * permute[] is the lookup table for converting huffman coded symbols + * into decoded symbols. base[] is the amount to subtract from the + * value of a huffman symbol of a given length when using permute[]. + * + * limit[] indicates the largest numerical value a symbol with a given + * number of bits can have. It lets us know when to stop reading. + * + * To use these, keep reading bits until value<=limit[bitcount] or + * you've read over 20 bits (error). Then the decoded symbol + * equals permute[hufcode_value-base[hufcode_bitcount]]. + */ + hufGroup=bd->groups+j; + hufGroup->minLen = minLen; + hufGroup->maxLen = maxLen; + /* Note that minLen can't be smaller than 1, so we adjust the base + and limit array pointers so we're not always wasting the first + entry. We do this again when using them (during symbol decoding).*/ + base=hufGroup->base-1; + limit=hufGroup->limit-1; + /* Calculate permute[] */ + pp = 0; + for(i=minLen;i<=maxLen;i++) + for(t=0;t<symCount;t++) + if(length[t]==i) hufGroup->permute[pp++] = t; + /* Count cumulative symbols coded for at each bit length */ + for (i=minLen;i<=maxLen;i++) temp[i]=limit[i]=0; + for (i=0;i<symCount;i++) temp[length[i]]++; + /* Calculate limit[] (the largest symbol-coding value at each bit + * length, which is (previous limit<<1)+symbols at this level), and + * base[] (number of symbols to ignore at each bit length, which is + * limit-cumulative count of symbols coded for already). */ + pp=t=0; + for (i=minLen; i<maxLen; i++) { + pp+=temp[i]; + limit[i]=pp-1; + pp<<=1; + base[i+1]=pp-(t+=temp[i]); } - /*-- MTF init --*/ - { - int ii, jj, kk; - kk = MTFA_SIZE-1; - for (ii = 256 / MTFL_SIZE - 1; ii >= 0; ii--) { - for (jj = MTFL_SIZE-1; jj >= 0; jj--) { - s->mtfa[kk] = (unsigned char)(ii * MTFL_SIZE + jj); - kk--; - } - s->mtfbase[ii] = kk + 1; - } + limit[maxLen]=pp+temp[maxLen]-1; + base[minLen]=0; + } + /* We've finished reading and digesting the block header. Now read this + block's huffman coded symbols from the file and undo the huffman coding + and run length encoding, saving the result into dbuf[dbufCount++]=uc */ + + /* Initialize symbol occurrence counters and symbol mtf table */ + memset(byteCount,0,256*sizeof(int)); + for(i=0;i<256;i++) mtfSymbol[i]=(unsigned char)i; + /* Loop through compressed symbols */ + runPos=dbufCount=symCount=selector=0; + for(;;) { + /* Determine which huffman coding group to use. */ + if(!(symCount--)) { + symCount=GROUP_SIZE-1; + if(selector>=nSelectors) return RETVAL_DATA_ERROR; + hufGroup=bd->groups+selectors[selector++]; + base=hufGroup->base-1; + limit=hufGroup->limit-1; } - /*-- end MTF init --*/ - - nblock = 0; - - if (! get_mtf_val_init()) { - goto save_state_and_return; + /* Read next huffman-coded symbol */ + i = hufGroup->minLen; + j=get_bits(bd, i); + for(;;) { + if (i > hufGroup->maxLen) return RETVAL_DATA_ERROR; + if (j <= limit[i]) break; + i++; + + j = (j << 1) | get_bits(bd,1); } - case BZ_X_MTF_1: - s->state = BZ_X_MTF_1; - if (! get_bits(s, &zvec, zn)) { - retVal = BZ_OK; - goto save_state_and_return; - } - while (1) { - if (zn > 20 /* the longest code */) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; - } - if (zvec <= gLimit[zn]) { - break; - } - zn++; - - case BZ_X_MTF_2: - s->state = BZ_X_MTF_2; - if (! get_bits(s, &zj, 1)) { - retVal = BZ_OK; - goto save_state_and_return; - } - zvec = (zvec << 1) | zj; - } - if (zvec - gBase[zn] < 0 || zvec - gBase[zn] >= BZ_MAX_ALPHA_SIZE) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; - } - nextSym = gPerm[zvec - gBase[zn]]; - - while (1) { - if (nextSym == EOB) { - break; - } - - if (nextSym == BZ_RUNA || nextSym == BZ_RUNB) { - es = -1; - N = 1; - do { - if (nextSym == BZ_RUNA) { - es = es + (0+1) * N; - } else { - if (nextSym == BZ_RUNB) { - es = es + (1+1) * N; - } - } - N = N * 2; - if (! get_mtf_val_init()) { - goto save_state_and_return; - } - case BZ_X_MTF_3: - s->state = BZ_X_MTF_3; - if (! get_bits(s, &zvec, zn)) { - retVal = BZ_OK; - goto save_state_and_return; - } - while (1) { - if (zn > 20 /* the longest code */) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; - } - if (zvec <= gLimit[zn]) { - break; - } - zn++; - - case BZ_X_MTF_4: - s->state = BZ_X_MTF_4; - if (! get_bits(s, &zj, 1)) { - retVal = BZ_OK; - goto save_state_and_return; - } - zvec = (zvec << 1) | zj; - } - if (zvec - gBase[zn] < 0 || zvec - gBase[zn] >= BZ_MAX_ALPHA_SIZE) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; - - } - nextSym = gPerm[zvec - gBase[zn]]; - } - while (nextSym == BZ_RUNA || nextSym == BZ_RUNB); - - es++; - uc = s->seqToUnseq[ s->mtfa[s->mtfbase[0]] ]; - s->unzftab[uc] += es; - - while (es > 0) { - if (nblock >= nblockMAX) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; - } - s->tt[nblock] = (unsigned int)uc; - nblock++; - es--; - } - continue; - } else { - if (nblock >= nblockMAX) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; - } - /*-- uc = MTF ( nextSym-1 ) --*/ - { - int ii, jj, kk, pp, lno, off; - unsigned int nn; - nn = (unsigned int)(nextSym - 1); - - if (nn < MTFL_SIZE) { - /* avoid general-case expense */ - pp = s->mtfbase[0]; - uc = s->mtfa[pp+nn]; - while (nn > 3) { - int z = pp+nn; - s->mtfa[(z) ] = s->mtfa[(z)-1]; - s->mtfa[(z)-1] = s->mtfa[(z)-2]; - s->mtfa[(z)-2] = s->mtfa[(z)-3]; - s->mtfa[(z)-3] = s->mtfa[(z)-4]; - nn -= 4; - } - while (nn > 0) { - s->mtfa[(pp+nn)] = s->mtfa[(pp+nn)-1]; nn--; - } - s->mtfa[pp] = uc; - } else { - /* general case */ - lno = nn / MTFL_SIZE; - off = nn % MTFL_SIZE; - pp = s->mtfbase[lno] + off; - uc = s->mtfa[pp]; - while (pp > s->mtfbase[lno]) { - s->mtfa[pp] = s->mtfa[pp-1]; - pp--; - } - s->mtfbase[lno]++; - while (lno > 0) { - s->mtfbase[lno]--; - s->mtfa[s->mtfbase[lno]] = s->mtfa[s->mtfbase[lno-1] + MTFL_SIZE - 1]; - lno--; - } - s->mtfbase[0]--; - s->mtfa[s->mtfbase[0]] = uc; - if (s->mtfbase[0] == 0) { - kk = MTFA_SIZE-1; - for (ii = 256 / MTFL_SIZE-1; ii >= 0; ii--) { - for (jj = MTFL_SIZE-1; jj >= 0; jj--) { - s->mtfa[kk] = s->mtfa[s->mtfbase[ii] + jj]; - kk--; - } - s->mtfbase[ii] = kk + 1; - } - } - } - } - /*-- end uc = MTF ( nextSym-1 ) --*/ - - s->unzftab[s->seqToUnseq[uc]]++; - s->tt[nblock] = (unsigned int)(s->seqToUnseq[uc]); - nblock++; - - if (! get_mtf_val_init()) { - goto save_state_and_return; - } - case BZ_X_MTF_5: - s->state = BZ_X_MTF_5; - if (! get_bits(s, &zvec, zn)) { - retVal = BZ_OK; - goto save_state_and_return; - } - while (1) { - if (zn > 20 /* the longest code */) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; - } - if (zvec <= gLimit[zn]) { - break; - } - zn++; - - case BZ_X_MTF_6: - s->state = BZ_X_MTF_6; - if (! get_bits(s, &zj, 1)) { - retVal = BZ_OK; - goto save_state_and_return; - } - zvec = (zvec << 1) | zj; - } - if (zvec - gBase[zn] < 0 || zvec - gBase[zn] >= BZ_MAX_ALPHA_SIZE) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; - } - nextSym = gPerm[zvec - gBase[zn]]; + /* Huffman decode nextSym (with bounds checking) */ + j-=base[i]; + if (j < 0 || j >= MAX_SYMBOLS) return RETVAL_DATA_ERROR; + nextSym = hufGroup->permute[j]; + /* If this is a repeated run, loop collecting data */ + if (nextSym == SYMBOL_RUNA || nextSym == SYMBOL_RUNB) { + /* If this is the start of a new run, zero out counter */ + if(!runPos) { + runPos = 1; + t = 0; + } + /* Neat trick that saves 1 symbol: instead of or-ing 0 or 1 at + each bit position, add 1 or 2 instead. For example, + 1011 is 1<<0 + 1<<1 + 2<<2. 1010 is 2<<0 + 2<<1 + 1<<2. + You can make any bit pattern that way using 1 less symbol than + the basic or 0/1 method (except all bits 0, which would use no + symbols, but a run of length 0 doesn't mean anything in this + context). Thus space is saved. */ + if (nextSym == SYMBOL_RUNA) t += runPos; + else t += 2*runPos; + runPos <<= 1; continue; } + /* When we hit the first non-run symbol after a run, we now know + how many times to repeat the last literal, so append that many + copies to our buffer of decoded symbols (dbuf) now. (The last + literal used is the one at the head of the mtfSymbol array.) */ + if(runPos) { + runPos=0; + if(dbufCount+t>=dbufSize) return RETVAL_DATA_ERROR; + + uc = symToByte[mtfSymbol[0]]; + byteCount[uc] += t; + while(t--) dbuf[dbufCount++]=uc; + } + /* Is this the terminating symbol? */ + if(nextSym>symTotal) break; + /* At this point, the symbol we just decoded indicates a new literal + character. Subtract one to get the position in the MTF array + at which this literal is currently to be found. (Note that the + result can't be -1 or 0, because 0 and 1 are RUNA and RUNB. + Another instance of the first symbol in the mtf array, position 0, + would have been handled as part of a run.) */ + if(dbufCount>=dbufSize) return RETVAL_DATA_ERROR; + i = nextSym - 1; + uc = mtfSymbol[i]; + memmove(mtfSymbol+1,mtfSymbol,i); + mtfSymbol[0] = uc; + uc=symToByte[uc]; + /* We have our literal byte. Save it into dbuf. */ + byteCount[uc]++; + dbuf[dbufCount++] = (unsigned int)uc; } - - /* Now we know what nblock is, we can do a better sanity - check on s->origPtr. - */ - if (s->origPtr < 0 || s->origPtr >= nblock) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; + /* At this point, we've finished reading huffman-coded symbols and + compressed runs from the input stream. There are dbufCount many of + them in dbuf[]. Now undo the Burrows-Wheeler transform on dbuf. + See http://dogma.net/markn/articles/bwt/bwt.htm + */ + + /* Now we know what dbufCount is, do a better sanity check on origPtr. */ + if (origPtr<0 || origPtr>=dbufCount) return RETVAL_DATA_ERROR; + /* Turn byteCount into cumulative occurrence counts of 0 to n-1. */ + j=0; + for(i=0;i<256;i++) { + k=j+byteCount[i]; + byteCount[i] = j; + j=k; } - s->state_out_len = 0; - s->state_out_ch = 0; - s->calculatedBlockCRC = 0xffffffffL; - s->state = BZ_X_OUTPUT; - - /*-- Set up cftab to facilitate generation of T^(-1) --*/ - s->cftab[0] = 0; - for (i = 1; i <= 256; i++) { - s->cftab[i] = s->unzftab[i-1]; + /* Figure out what order dbuf would be in if we sorted it. */ + for (i=0;i<dbufCount;i++) { + uc = (unsigned char)(dbuf[i] & 0xff); + dbuf[byteCount[uc]] |= (i << 8); + byteCount[uc]++; } - for (i = 1; i <= 256; i++) { - s->cftab[i] += s->cftab[i-1]; + /* blockRandomised support would go here. */ + + /* Using i as position, j as previous character, t as current character, + and uc as run count */ + bd->dataCRC = 0xffffffffL; + /* Decode first byte by hand to initialize "previous" byte. Note that it + doesn't get output, and if the first three characters are identical + it doesn't qualify as a run (hence uc=255, which will either wrap + to 1 or get reset). */ + if(dbufCount) { + bd->writePos=dbuf[origPtr]; + bd->writeCurrent=(unsigned char)(bd->writePos&0xff); + bd->writePos>>=8; + bd->writeRun=-1; } + bd->writeCount=dbufCount; - /*-- compute the T^(-1) vector --*/ - for (i = 0; i < nblock; i++) { - uc = (unsigned char)(s->tt[i] & 0xff); - s->tt[s->cftab[uc]] |= (i << 8); - s->cftab[uc]++; - } - - s->tPos = s->tt[s->origPtr] >> 8; - s->nblock_used = 0; - if (s->blockRandomised) { - s->rNToGo = 0; - s->rTPos = 0; - s->k0 = bz_get_fast(s); - - s->nblock_used++; - bz_rand_udp_mask(s); - s->k0 ^= ((s->rNToGo == 1) ? 1 : 0); - } else { - s->k0 = bz_get_fast(s); - s->nblock_used++; - } - - retVal = BZ_OK; - goto save_state_and_return; - -endhdr_2: - case BZ_X_ENDHDR_2: - s->state = BZ_X_ENDHDR_2; - if (! get_bits(s, &uc, 8)) { - retVal = BZ_OK; - goto save_state_and_return; - } - if (uc != 0x72) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; - } - - case BZ_X_ENDHDR_3: - s->state = BZ_X_ENDHDR_3; - if (! get_bits(s, &uc, 8)) { - retVal = BZ_OK; - goto save_state_and_return; - } - if (uc != 0x45) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; - } - - case BZ_X_ENDHDR_4: - s->state = BZ_X_ENDHDR_4; - if (! get_bits(s, &uc, 8)) { - retVal = BZ_OK; - goto save_state_and_return; - } - if (uc != 0x38) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; - } - - case BZ_X_ENDHDR_5: - s->state = BZ_X_ENDHDR_5; - if (! get_bits(s, &uc, 8)) { - retVal = BZ_OK; - goto save_state_and_return; - } - if (uc != 0x50) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; - } - - case BZ_X_ENDHDR_6: - s->state = BZ_X_ENDHDR_6; - if (! get_bits(s, &uc, 8)) { - retVal = BZ_OK; - goto save_state_and_return; - } - if (uc != 0x90) { - retVal = BZ_DATA_ERROR; - goto save_state_and_return; - } - s->storedCombinedCRC = 0; - - case BZ_X_CCRC_1: - s->state = BZ_X_CCRC_1; - if (! get_bits(s, &uc, 8)) { - retVal = BZ_OK; - goto save_state_and_return; - } - s->storedCombinedCRC = (s->storedCombinedCRC << 8) | ((unsigned int)uc); - case BZ_X_CCRC_2: - s->state = BZ_X_CCRC_2; - if (! get_bits(s, &uc, 8)) { - retVal = BZ_OK; - goto save_state_and_return; - } - s->storedCombinedCRC = (s->storedCombinedCRC << 8) | ((unsigned int)uc); - - case BZ_X_CCRC_3: - s->state = BZ_X_CCRC_3; - if (! get_bits(s, &uc, 8)) { - retVal = BZ_OK; - goto save_state_and_return; - } - s->storedCombinedCRC = (s->storedCombinedCRC << 8) | ((unsigned int)uc); - - case BZ_X_CCRC_4: - s->state = BZ_X_CCRC_4; - if (! get_bits(s, &uc, 8)) { - retVal = BZ_OK; - goto save_state_and_return; - } - s->storedCombinedCRC = (s->storedCombinedCRC << 8) | ((unsigned int)uc); - - s->state = BZ_X_IDLE; - retVal = BZ_STREAM_END; - goto save_state_and_return; - - } - -save_state_and_return: - s->save_i = i; - s->save_j = j; - s->save_t = t; - s->save_alphaSize = alphaSize; - s->save_nGroups = nGroups; - s->save_nSelectors = nSelectors; - s->save_EOB = EOB; - s->save_groupNo = groupNo; - s->save_groupPos = groupPos; - s->save_nextSym = nextSym; - s->save_nblockMAX = nblockMAX; - s->save_nblock = nblock; - s->save_es = es; - s->save_N = N; - s->save_curr = curr; - s->save_zt = zt; - s->save_zn = zn; - s->save_zvec = zvec; - s->save_zj = zj; - s->save_gSel = gSel; - s->save_gMinlen = gMinlen; - s->save_gLimit = gLimit; - s->save_gBase = gBase; - s->save_gPerm = gPerm; - - return retVal; + return RETVAL_OK; } -extern void BZ2_bzReadClose(void) +/* Flush output buffer to disk */ +extern void flush_bunzip_outbuf(bunzip_data *bd, int out_fd) { - if (bzf->initialisedOk) { - bz_stream *strm = &(bzf->strm); - DState *s; - if (strm == NULL) { - return; - } - s = strm->state; - if ((s == NULL) || (s->strm != strm)) { - return; - } - free(s->tt); - free(strm->state); - strm->state = NULL; - return; + if(bd->outbufPos) { + if(write(out_fd, bd->outbuf, bd->outbufPos) != bd->outbufPos) + longjmp(bd->jmpbuf,RETVAL_UNEXPECTED_OUTPUT_EOF); + bd->outbufPos=0; } - free(bzf); } -static void unRLE_obuf_to_output_FAST(DState *s) -{ - unsigned char k1; - - if (s->blockRandomised) { - while (1) { - /* try to finish existing run */ - while (1) { - if (s->strm->avail_out == 0) { - return; - } - if (s->state_out_len == 0) { - break; - } - *((unsigned char *)(s->strm->next_out)) = s->state_out_ch; - s->calculatedBlockCRC = (s->calculatedBlockCRC << 8) ^ - BZ2_crc32Table[(s->calculatedBlockCRC >> 24) ^ - ((unsigned char)s->state_out_ch)]; - s->state_out_len--; - s->strm->next_out++; - s->strm->avail_out--; - } - - /* can a new run be started? */ - if (s->nblock_used == s->save_nblock+1) { - return; - } - s->state_out_len = 1; - s->state_out_ch = s->k0; - k1 = bz_get_fast(s); - bz_rand_udp_mask(s); - k1 ^= ((s->rNToGo == 1) ? 1 : 0); - s->nblock_used++; - if (s->nblock_used == s->save_nblock+1) { - continue; - } - if (k1 != s->k0) { - s->k0 = k1; - continue; - } - s->state_out_len = 2; - k1 = bz_get_fast(s); - bz_rand_udp_mask(s); - k1 ^= ((s->rNToGo == 1) ? 1 : 0); - s->nblock_used++; - if (s->nblock_used == s->save_nblock+1) { - continue; - } - if (k1 != s->k0) { - s->k0 = k1; - continue; - } - s->state_out_len = 3; - k1 = bz_get_fast(s); - bz_rand_udp_mask(s); - k1 ^= ((s->rNToGo == 1) ? 1 : 0); - s->nblock_used++; - if (s->nblock_used == s->save_nblock+1) { - continue; - } - if (k1 != s->k0) { - s->k0 = k1; - continue; +/* Undo burrows-wheeler transform on intermediate buffer to produce output. + If !len, write up to len bytes of data to buf. Otherwise write to out_fd. + Returns len ? bytes written : RETVAL_OK. Notice all errors negative #'s. */ +extern int write_bunzip_data(bunzip_data *bd, int out_fd, char *outbuf, int len) +{ + unsigned int *dbuf=bd->dbuf; + int count,pos,current, run,copies,outbyte,previous,gotcount=0; + + for(;;) { + /* If last read was short due to end of file, return last block now */ + if(bd->writeCount<0) return bd->writeCount; + /* If we need to refill dbuf, do it. */ + if(!bd->writeCount) { + int i=read_bunzip_data(bd); + if(i) { + if(i==RETVAL_LAST_BLOCK) { + bd->writeCount=i; + return gotcount; + } else return i; } - - k1 = bz_get_fast(s); - bz_rand_udp_mask(s); - k1 ^= ((s->rNToGo == 1) ? 1 : 0); - s->nblock_used++; - s->state_out_len = ((int)k1) + 4; - s->k0 = bz_get_fast(s); - bz_rand_udp_mask(s); - s->k0 ^= ((s->rNToGo == 1) ? 1 : 0); - s->nblock_used++; } - } else { - /* restore */ - unsigned int c_calculatedBlockCRC = s->calculatedBlockCRC; - unsigned char c_state_out_ch = s->state_out_ch; - int c_state_out_len = s->state_out_len; - int c_nblock_used = s->nblock_used; - int c_k0 = s->k0; - unsigned int *c_tt = s->tt; - unsigned int c_tPos = s->tPos; - char *cs_next_out = s->strm->next_out; - unsigned int cs_avail_out = s->strm->avail_out; - /* end restore */ - - int s_save_nblockPP = s->save_nblock+1; - - while (1) { - /* try to finish existing run */ - if (c_state_out_len > 0) { - while (TRUE) { - if (cs_avail_out == 0) { - goto return_notr; - } - if (c_state_out_len == 1) { - break; - } - *((unsigned char *)(cs_next_out)) = c_state_out_ch; - c_calculatedBlockCRC = (c_calculatedBlockCRC << 8) ^ - BZ2_crc32Table[(c_calculatedBlockCRC >> 24) ^ - ((unsigned char)c_state_out_ch)]; - c_state_out_len--; - cs_next_out++; - cs_avail_out--; - } -s_state_out_len_eq_one: - { - if (cs_avail_out == 0) { - c_state_out_len = 1; - goto return_notr; - } - *((unsigned char *)(cs_next_out)) = c_state_out_ch; - c_calculatedBlockCRC = (c_calculatedBlockCRC << 8) ^ - BZ2_crc32Table[(c_calculatedBlockCRC >> 24) ^ - ((unsigned char)c_state_out_ch)]; - cs_next_out++; - cs_avail_out--; - } - } - /* can a new run be started? */ - if (c_nblock_used == s_save_nblockPP) { - c_state_out_len = 0; goto return_notr; - } - c_state_out_ch = c_k0; - c_tPos = c_tt[c_tPos]; - k1 = (unsigned char)(c_tPos & 0xff); - c_tPos >>= 8; - - c_nblock_used++; - - if (k1 != c_k0) { - c_k0 = k1; - goto s_state_out_len_eq_one; - } - - if (c_nblock_used == s_save_nblockPP) { - goto s_state_out_len_eq_one; - } - - c_state_out_len = 2; - c_tPos = c_tt[c_tPos]; - k1 = (unsigned char)(c_tPos & 0xff); - c_tPos >>= 8; - - c_nblock_used++; - if (c_nblock_used == s_save_nblockPP) { - continue; - } - if (k1 != c_k0) { - c_k0 = k1; - continue; - } - - c_state_out_len = 3; - c_tPos = c_tt[c_tPos]; - k1 = (unsigned char)(c_tPos & 0xff); - c_tPos >>= 8; - - c_nblock_used++; - if (c_nblock_used == s_save_nblockPP) { - continue; + /* Loop generating output */ + count=bd->writeCount; + pos=bd->writePos; + current=bd->writeCurrent; + run=bd->writeRun; + while(count) { + /* If somebody (like busybox tar) wants a certain number of bytes of + data from memory instead of written to a file, humor them */ + if(len && bd->outbufPos>=len) goto dataus_interruptus; + count--; + /* Follow sequence vector to undo Burrows-Wheeler transform */ + previous=current; + pos=dbuf[pos]; + current=pos&0xff; + pos>>=8; + /* Whenever we see 3 consecutive copies of the same byte, + the 4th is a repeat count */ + if(run++==3) { + copies=current; + outbyte=previous; + current=-1; + } else { + copies=1; + outbyte=current; } - if (k1 != c_k0) { - c_k0 = k1; - continue; + /* Output bytes to buffer, flushing to file if necessary */ + while(copies--) { + if(bd->outbufPos == IOBUF_SIZE) flush_bunzip_outbuf(bd,out_fd); + bd->outbuf[bd->outbufPos++] = outbyte; + bd->dataCRC = (bd->dataCRC << 8) + ^ bd->crc32Table[(bd->dataCRC >> 24) ^ outbyte]; } - - c_tPos = c_tt[c_tPos]; - k1 = (unsigned char)(c_tPos & 0xff); - c_tPos >>= 8; - - c_nblock_used++; - c_state_out_len = ((int)k1) + 4; - - c_tPos = c_tt[c_tPos]; - c_k0 = (unsigned char)(c_tPos & 0xff); - c_tPos >>= 8; - - c_nblock_used++; + if(current!=previous) run=0; } - -return_notr: - - /* save */ - s->calculatedBlockCRC = c_calculatedBlockCRC; - s->state_out_ch = c_state_out_ch; - s->state_out_len = c_state_out_len; - s->nblock_used = c_nblock_used; - s->k0 = c_k0; - s->tt = c_tt; - s->tPos = c_tPos; - s->strm->next_out = cs_next_out; - s->strm->avail_out = cs_avail_out; - /* end save */ - } -} -static inline -int BZ2_bzDecompress(bz_stream *strm) -{ - DState* s; - s = strm->state; - - while (1) { - if (s->state == BZ_X_IDLE) { - return BZ_SEQUENCE_ERROR; + /* Decompression of this block completed successfully */ + bd->dataCRC=~(bd->dataCRC); + bd->totalCRC=((bd->totalCRC << 1) | (bd->totalCRC >> 31)) ^ bd->dataCRC; + /* If this block had a CRC error, force file level CRC error. */ + if(bd->dataCRC!=bd->headerCRC) { + bd->totalCRC=bd->headerCRC+1; + return RETVAL_LAST_BLOCK; } - if (s->state == BZ_X_OUTPUT) { - unRLE_obuf_to_output_FAST(s); - if (s->nblock_used == s->save_nblock+1 && s->state_out_len == 0) { - s->calculatedBlockCRC = ~(s->calculatedBlockCRC); - if (s->calculatedBlockCRC != s->storedBlockCRC) { - return BZ_DATA_ERROR; - } - s->calculatedCombinedCRC = (s->calculatedCombinedCRC << 1) | (s->calculatedCombinedCRC >> 31); - s->calculatedCombinedCRC ^= s->calculatedBlockCRC; - s->state = BZ_X_BLKHDR_1; - } else { - return BZ_OK; - } - } - if (s->state >= BZ_X_MAGIC_1) { - int r = BZ2_decompress(s); - if (r == BZ_STREAM_END) { - if (s->calculatedCombinedCRC != s->storedCombinedCRC) { - return BZ_DATA_ERROR; - } - return r; - } - if (s->state != BZ_X_OUTPUT) { - return r; +dataus_interruptus: + bd->writeCount=count; + if(len) { + gotcount+=bd->outbufPos; + memcpy(outbuf,bd->outbuf,len); + /* If we got enough data, checkpoint loop state and return */ + if((len-=bd->outbufPos)<1) { + bd->outbufPos-=len; + if(bd->outbufPos) + memmove(bd->outbuf,bd->outbuf+len,bd->outbufPos); + bd->writePos=pos; + bd->writeCurrent=current; + bd->writeRun=run; + return gotcount; } } } - - return(0); /*NOTREACHED*/ } -extern ssize_t read_bz2(int fd, void *buf, size_t count) +/* Allocate the structure, read file header. If !len, src_fd contains + filehandle to read from. Else inbuf contains data. */ +extern int start_bunzip(bunzip_data **bdp, int src_fd, char *inbuf, int len) { - int n, ret; - - bzerr = BZ_OK; - if (count == 0) { - return(0); + bunzip_data *bd; + unsigned int i,j,c; + + /* Figure out how much data to allocate */ + i=sizeof(bunzip_data); + if(!len) i+=IOBUF_SIZE; + /* Allocate bunzip_data. Most fields initialize to zero. */ + if(!(bd=*bdp=malloc(i))) return RETVAL_OUT_OF_MEMORY; + memset(bd,0,sizeof(bunzip_data)); + if(len) { + bd->inbuf=inbuf; + bd->inbufCount=len; + bd->in_fd=-1; + } else { + bd->inbuf=(char *)(bd+1); + bd->in_fd=src_fd; } - bzf->strm.avail_out = count; - bzf->strm.next_out = buf; - - while (1) { - if (bzf->strm.avail_in == 0) { - n = bb_xread(bzf->fd, bzf->buf, BZ_MAX_UNUSED); - if (n == 0) { - break; - } - bzf->bufN = n; - bzf->strm.avail_in = bzf->bufN; - bzf->strm.next_in = bzf->buf; - } - - ret = BZ2_bzDecompress(&(bzf->strm)); - - if ((ret != BZ_OK) && (ret != BZ_STREAM_END)) { - bb_error_msg_and_die("Error decompressing"); - } - - if (ret == BZ_STREAM_END) { - bzerr = BZ_STREAM_END; - return(count - bzf->strm.avail_out); - } - if (bzf->strm.avail_out == 0) { - bzerr = BZ_OK; - return(count); - } + /* Init the CRC32 table (big endian) */ + for(i=0;i<256;i++) { + c=i<<24; + for(j=8;j;j--) + c=c&0x80000000 ? (c<<1)^0x04c11db7 : (c<<1); + bd->crc32Table[i]=c; } - return(0); + /* Setup for I/O error handling via longjmp */ + i=setjmp(bd->jmpbuf); + if(i) return i; + /* Ensure that file starts with "BZh" */ + for(i=0;i<3;i++) if(get_bits(bd,8)!="BZh"[i]) return RETVAL_NOT_BZIP_DATA; + /* Next byte ascii '1'-'9', indicates block size in units of 100k of + uncompressed data. Allocate intermediate buffer for block. */ + i=get_bits(bd,8); + if (i<'1' || i>'9') return RETVAL_NOT_BZIP_DATA; + bd->dbufSize=100000*(i-'0'); + if(!(bd->dbuf=malloc(bd->dbufSize * sizeof(int)))) + return RETVAL_OUT_OF_MEMORY; + return RETVAL_OK; } -extern void BZ2_bzReadOpen(int fd, void *unused, int nUnused) +extern char *uncompressStream(int src_fd, int dst_fd) { - DState *s; - - bzf = xmalloc(sizeof(bzFile)); - bzf->initialisedOk = FALSE; - bzf->fd = fd; - bzf->bufN = 0; - - s = xmalloc(sizeof(DState)); - s->strm = &bzf->strm; - s->state = BZ_X_MAGIC_1; - s->bsLive = 0; - s->bsBuff = 0; - s->calculatedCombinedCRC = 0; - s->tt = NULL; - s->currBlockNo = 0; - bzf->strm.state = s; + bunzip_data *bd; + int i; - while (nUnused > 0) { - bzf->buf[bzf->bufN] = *((unsigned char *)(unused)); - bzf->bufN++; - unused = ((void *)( 1 + ((unsigned char *)(unused)) )); - nUnused--; + if(!(i=start_bunzip(&bd,src_fd,0,0))) { + i=write_bunzip_data(bd,dst_fd,0,0); + if(i==RETVAL_LAST_BLOCK && bd->headerCRC==bd->totalCRC) i=RETVAL_OK; } - bzf->strm.avail_in = bzf->bufN; - bzf->strm.next_in = bzf->buf; + flush_bunzip_outbuf(bd,dst_fd); + if(bd->dbuf) free(bd->dbuf); + free(bd); + return bunzip_errors[-i]; +} - bzf->initialisedOk = TRUE; +/* This new version is not yet properly integrated with tar */ +extern ssize_t read_bz2(int fd, void *buf, size_t count) +{ +#warning FIXME + return(0); +} +extern void BZ2_bzReadOpen(int fd, void *unused, int nUnused) +{ +#warning FIXME return; } - -extern unsigned char uncompressStream(int src_fd, int dst_fd) +extern void BZ2_bzReadClose(void) { - unsigned char unused[BZ_MAX_UNUSED]; - unsigned char *unusedTmp; - unsigned char obuf[5000]; - int nread; - int nUnused; - int streamNo; - int i; - - nUnused = 0; - streamNo = 0; - - while(1) { - BZ2_bzReadOpen(src_fd, unused, nUnused); - streamNo++; - - while (bzerr == BZ_OK) { - nread = read_bz2(src_fd, obuf, 5000); - if (bzerr == BZ_DATA_ERROR_MAGIC) { - bb_error_msg_and_die("invalid magic"); - } - if (((bzerr == BZ_OK) || (bzerr == BZ_STREAM_END)) && (nread > 0)) { - if (write(dst_fd, obuf, nread) != nread) { - BZ2_bzReadClose(); - bb_perror_msg_and_die("Couldnt write to file"); - } - } - } - nUnused = bzf->strm.avail_in; - unusedTmp = bzf->strm.next_in; - - for (i = 0; i < nUnused; i++) { - unused[i] = unusedTmp[i]; - } - BZ2_bzReadClose(); - if (nUnused == 0) { - break; - } - } - - close(src_fd); - if (dst_fd != fileno(stdout)) { - close(dst_fd); - } - return TRUE; +#warning FIXME } +#if 0 +/* Dumb little test thing, decompress stdin to stdout */ +int main(int argc, char *argv[]) +{ + char *c=uncompressStream(0,1); + fprintf(stderr,"\n%s\n", c ? c : "Completed OK"); +} +#endif |