/* * NuFX archive manipulation library * Copyright (C) 2000 by Andy McFadden, All Rights Reserved. * This is free software; you can redistribute it and/or modify it under the * terms of the GNU Library General Public License, see the file COPYING.LIB. * * This is the LZW implementation found in the UNIX "compress" command, * sometimes referred to as "LZC". GS/ShrinkIt v1.1 can unpack threads * in LZC format, P8 ShrinkIt cannot. The only other application that * is known to create LZC threads is the original NuLib. * * There's a lot of junk in here for the sake of smaller systems (e.g. MSDOS) * and pre-ANSI compilers. For the most part it has been left unchanged. * I have done some minor reformatting, and have undone the authors' * penchant for assigning variables inside function call statements, but * for the most part it is as it was. (A much cleaner implementation * could probably be derived by adapting the NufxLib Lzw.c code...) */ #include "NufxLibPriv.h" #ifdef ENABLE_LZC #define DEBUG_LZC /* * Selected definitions from compress.h. */ typedef unsigned short CODE; typedef unsigned char UCHAR; typedef unsigned int INTCODE; typedef unsigned int HASH; typedef int FLAG; #ifndef FALSE /* let's get some sense to this */ #define FALSE 0 #define TRUE !FALSE #endif #define CONST const #define FAR #define NULLPTR(type) ((type FAR *) NULL) #define ALLOCTYPE void #define INITBITS 9 #define MINBITS 12 #define MAXMAXBITS 16 #define MAXBITS MAXMAXBITS #define DFLTBITS MAXBITS #define UNUSED ((CODE)0) /* Indicates hash table value unused */ #define CLEAR ((CODE)256) /* Code requesting table to be cleared */ #define FIRSTFREE ((CODE)257) /* First free code for token encoding */ #define MAXTOKLEN 512 /* Max chars in token; size of buffer */ #define OK kNuErrNone /* Result codes from functions: */ #define BIT_MASK 0x1f #define BLOCK_MASK 0x80 #define CHECK_GAP 10000L /* ratio check interval, for COMP40 */ static UCHAR gNu_magic_header[] = { 0x1F,0x9D }; /* don't need these */ /*#define SPLIT_HT 1*/ /*#define SPLIT_PFX 1*/ /*#define COMP40 1*/ #define NOMEM kNuErrMalloc /* Ran out of memory */ #define TOKTOOBIG kNuErrBadData /* Token longer than MAXTOKLEN chars */ #define READERR kNuErrFileRead /* I/O error on input */ #define WRITEERR kNuErrFileWrite /* I/O error on output */ #define CODEBAD kNuErrBadData /* Infile contained a bad token code */ #define TABLEBAD kNuErrInternal /* The tables got corrupted (!) */ #define NOSAVING kNuErrNone /* no saving in file size */ /* * Normally in COMPUSI.UNI. */ static inline ALLOCTYPE FAR * Nu_LZC_emalloc(NuArchive* pArchive, unsigned int x, int y) { return Nu_Malloc(pArchive, x*y); } static inline void Nu_LZC_efree(NuArchive* pArchive, ALLOCTYPE FAR * ptr) { return Nu_Free(pArchive, ptr); } /*@H************************ < COMPRESS API > **************************** * $@(#) compapi.c,v 4.3d 90/01/18 03:00:00 don Release ^ * * * * compress : compapi.c * * * * port by : Donald J. Gloistein * * * * Source, Documentation, Object Code: * * released to Public Domain. This code is based on code as documented * * below in release notes. * * * *--------------------------- Module Description --------------------------* * Contains source code for modified Lempel-Ziv method (LZW) compression * * and decompression. * * * * This code module can be maintained to keep current on releases on the * * Unix system. The command shell and dos modules can remain the same. * * * *--------------------------- Implementation Notes --------------------------* * * * compiled with : compress.h compress.fns compress.c * * linked with : compress.obj compusi.obj * * * * problems: * * * * * * CAUTION: Uses a number of defines for access and speed. If you change * * anything, make sure about side effects. * * * * Compression: * * Algorithm: use open addressing double hashing (no chaining) on the * * prefix code / next character combination. We do a variant of Knuth's * * algorithm D (vol. 3, sec. 6.4) along with G. Knott's relatively-prime * * secondary probe. Here, the modular division first probe is gives way * * to a faster exclusive-or manipulation. * * Also block compression with an adaptive reset was used in original code, * * whereby the code table is cleared when the compression ration decreases * * but after the table fills. This was removed from this edition. The table * * is re-sized at this point when it is filled , and a special CLEAR code is * * generated for the decompressor. This results in some size difference from * * straight version 4.0 joe Release. But it is fully compatible in both v4.0 * * and v4.01 * * * * Decompression: * * This routine adapts to the codes in the file building the "string" table * * on-the-fly; requiring no table to be stored in the compressed file. The * * tables used herein are shared with those of the compress() routine. * * * * Initials ---- Name --------------------------------- * * DjG Donald J. Gloistein, current port to MsDos 16 bit * * Plus many others, see rev.hst file for full list * * LvR Lyle V. Rains, many thanks for improved implementation * * of the compression and decompression routines. * *************************************************************************@H*/ #include /* * LZC state, largely variables with non-local scope. */ typedef struct LZCState { NuArchive* pArchive; int doCalcCRC; ushort crc; /* compression */ NuStraw* pStraw; FILE* outfp; long uncompRemaining; /* expansion */ FILE* infp; NuFunnel* pFunnel; ushort* pCrc; long compRemaining; /* * Globals from Compress sources. */ int offset; long int in_count ; /* length of input */ long int bytes_out; /* length of compressed output */ INTCODE prefxcode, nextfree; INTCODE highcode; INTCODE maxcode; HASH hashsize; int bits; char FAR *sfx; #if (SPLIT_PFX) CODE FAR *pfx[2]; #else CODE FAR *pfx; #endif #if (SPLIT_HT) CODE FAR *ht[2]; #else CODE FAR *ht; #endif #ifdef COMP40 long int ratio; long checkpoint; /* initialized to CHECK_GAP */ #endif #ifdef DEBUG_LZC int debug; /* initialized to FALSE */ #endif NuError exit_stat; int maxbits; /* initialized to DFLTBITS */ int block_compress; /* initialized to BLOCK_MASK */ /* * Static local variables. Some of these were explicitly initialized * to zero. */ INTCODE oldmaxcode; /* alloc_tables */ HASH oldhashsize; /* alloc_tables */ int oldbits; /* putcode */ UCHAR outbuf[MAXBITS]; /* putcode */ int prevbits; /* nextcode */ int size; /* nextcode */ UCHAR inbuf[MAXBITS]; /* nextcode */ } LZCState; /* * The following two parameter tables are the hash table sizes and * maximum code values for various code bit-lengths. The requirements * are that Hashsize[n] must be a prime number and Maxcode[n] must be less * than Maxhash[n]. Table occupancy factor is (Maxcode - 256)/Maxhash. * Note: I am using a lower Maxcode for 16-bit codes in order to * keep the hash table size less than 64k entries. */ static CONST HASH gNu_hs[] = { 0x13FF, /* 12-bit codes, 75% occupancy */ 0x26C3, /* 13-bit codes, 80% occupancy */ 0x4A1D, /* 14-bit codes, 85% occupancy */ 0x8D0D, /* 15-bit codes, 90% occupancy */ 0xFFD9 /* 16-bit codes, 94% occupancy, 6% of code values unused */ }; #define Hashsize(maxb) (gNu_hs[(maxb) -MINBITS]) static CONST INTCODE gNu_mc[] = { 0x0FFF, /* 12-bit codes */ 0x1FFF, /* 13-bit codes */ 0x3FFF, /* 14-bit codes */ 0x7FFF, /* 15-bit codes */ 0xEFFF /* 16-bit codes, 6% of code values unused */ }; #define Maxcode(maxb) (gNu_mc[(maxb) -MINBITS]) #ifdef __STDC__ #ifdef DEBUG_LZC #define allocx(type, ptr, size) \ (((ptr) = (type FAR *) Nu_LZC_emalloc(pArchive, (unsigned int)(size),sizeof(type))) == NULLPTR(type) \ ? (DBUG(("%s: "#ptr" -- ", "LZC")), NOMEM) : OK \ ) #else #define allocx(type,ptr,size) \ (((ptr) = (type FAR *) Nu_LZC_emalloc(pArchive, (unsigned int)(size),sizeof(type))) == NULLPTR(type) \ ? NOMEM : OK \ ) #endif #else #define allocx(type,ptr,size) \ (((ptr) = (type FAR *) Nu_LZC_emalloc(, pArchive, (unsigned int)(size),sizeof(type))) == NULLPTR(type) \ ? NOMEM : OK \ ) #endif #define free_array(type,ptr,offset) \ if (ptr != NULLPTR(type)) { \ Nu_LZC_efree(pArchive, (ALLOCTYPE FAR *)((ptr) + (offset))); \ (ptr) = NULLPTR(type); \ } /* * Macro to allocate new memory to a pointer with an offset value. */ #define alloc_array(type, ptr, size, offset) \ ( allocx(type, ptr, (size) - (offset)) != OK \ ? NOMEM \ : (((ptr) -= (offset)), OK) \ ) /*static char FAR *sfx = NULLPTR(char) ;*/ #define suffix(code) pLzcState->sfx[code] #if (SPLIT_PFX) /*static CODE FAR *pfx[2] = {NULLPTR(CODE), NULLPTR(CODE)};*/ #else /*static CODE FAR *pfx = NULLPTR(CODE);*/ #endif #if (SPLIT_HT) /*static CODE FAR *ht[2] = {NULLPTR(CODE),NULLPTR(CODE)};*/ #else /*static CODE FAR *ht = NULLPTR(CODE);*/ #endif static int Nu_LZC_alloc_tables(LZCState* pLzcState, INTCODE newmaxcode, HASH newhashsize) { NuArchive* pArchive = pLzcState->pArchive; /*static INTCODE oldmaxcode = 0;*/ /*static HASH oldhashsize = 0;*/ if (newhashsize > pLzcState->oldhashsize) { #if (SPLIT_HT) free_array(CODE,pLzcState->ht[1], 0); free_array(CODE,pLzcState->ht[0], 0); #else free_array(CODE,pLzcState->ht, 0); #endif pLzcState->oldhashsize = 0; } if (newmaxcode > pLzcState->oldmaxcode) { #if (SPLIT_PFX) free_array(CODE,pLzcState->pfx[1], 128); free_array(CODE,pLzcState->pfx[0], 128); #else free_array(CODE,pLzcState->pfx, 256); #endif free_array(char,pLzcState->sfx, 256); if ( alloc_array(char, pLzcState->sfx, newmaxcode + 1, 256) #if (SPLIT_PFX) || alloc_array(CODE, pLzcState->pfx[0], (newmaxcode + 1) / 2, 128) || alloc_array(CODE, pLzcState->pfx[1], (newmaxcode + 1) / 2, 128) #else || alloc_array(CODE, pLzcState->pfx, (newmaxcode + 1), 256) #endif ) { pLzcState->oldmaxcode = 0; pLzcState->exit_stat = NOMEM; return(NOMEM); } pLzcState->oldmaxcode = newmaxcode; } if (newhashsize > pLzcState->oldhashsize) { if ( #if (SPLIT_HT) alloc_array(CODE, pLzcState->ht[0], (newhashsize / 2) + 1, 0) || alloc_array(CODE, pLzcState->ht[1], newhashsize / 2, 0) #else alloc_array(CODE, pLzcState->ht, newhashsize, 0) #endif ) { pLzcState->oldhashsize = 0; pLzcState->exit_stat = NOMEM; return(NOMEM); } pLzcState->oldhashsize = newhashsize; } return (OK); } # if (SPLIT_PFX) /* * We have to split pfx[] table in half, * because it's potentially larger than 64k bytes. */ # define prefix(code) (pLzcState->pfx[(code) & 1][(code) >> 1]) # else /* * Then pfx[] can't be larger than 64k bytes, * or we don't care if it is, so we don't split. */ # define prefix(code) (pLzcState->pfx[code]) # endif /* The initializing of the tables can be done quicker with memset() */ /* but this way is portable through out the memory models. */ /* If you use Microsoft halloc() to allocate the arrays, then */ /* include the pragma #pragma function(memset) and make sure that */ /* the length of the memory block is not greater than 64K. */ /* This also means that you MUST compile in a model that makes the */ /* default pointers to be far pointers (compact or large models). */ /* See the file COMPUSI.DOS to modify function emalloc(). */ # if (SPLIT_HT) /* * We have to split ht[] hash table in half, * because it's potentially larger than 64k bytes. */ # define probe(hash) (pLzcState->ht[(hash) & 1][(hash) >> 1]) # define init_tables() \ { \ hash = pLzcState->hashsize >> 1; \ pLzcState->ht[0][hash] = 0; \ while (hash--) pLzcState->ht[0][hash] = pLzcState->ht[1][hash] = 0; \ pLzcState->highcode = ~(~(INTCODE)0 << (pLzcState->bits = INITBITS)); \ pLzcState->nextfree = (pLzcState->block_compress ? FIRSTFREE : 256); \ } # else /* * Then ht[] can't be larger than 64k bytes, * or we don't care if it is, so we don't split. */ # define probe(hash) (pLzcState->ht[hash]) # define init_tables() \ { \ hash = pLzcState->hashsize; \ while (hash--) pLzcState->ht[hash] = 0; \ pLzcState->highcode = ~(~(INTCODE)0 << (pLzcState->bits = INITBITS)); \ pLzcState->nextfree = (pLzcState->block_compress ? FIRSTFREE : 256); \ } # endif /* * =========================================================================== * Compression * =========================================================================== */ static void Nu_prratio(long int num, long int den) { register int q; /* Doesn't need to be long */ if(num > 214748L) { /* 2147483647/10000 */ q = (int) (num / (den / 10000L)); } else { q = (int) (10000L * num / den); /* Long calculations, though */ } if (q < 0) { DBUG(("-")); q = -q; } DBUG(("%d.%02d%%", q / 100, q % 100)); } #ifdef COMP40 /* table clear for block compress */ /* this is for adaptive reset present in version 4.0 joe release */ /* DjG, sets it up and returns TRUE to compress and FALSE to not compress */ static int Nu_LZC_cl_block(LZCState* pLzcState) { register long int rat; pLzcState->checkpoint = pLzcState->in_count + CHECK_GAP; #ifdef DEBUG_LZC if ( pLzcState->debug ) { DBUG(( "count: %ld, ratio: ", pLzcState->in_count )); Nu_prratio ( pLzcState->in_count, pLzcState->bytes_out ); DBUG(( "\n")); } #endif if(pLzcState->in_count > 0x007fffff) { /* shift will overflow */ rat = pLzcState->bytes_out >> 8; if(rat == 0) /* Don't divide by zero */ rat = 0x7fffffff; else rat = pLzcState->in_count / rat; } else rat = (pLzcState->in_count << 8) / pLzcState->bytes_out; /* 8 fractional bits */ if ( rat > pLzcState->ratio ){ pLzcState->ratio = rat; return FALSE; } else { pLzcState->ratio = 0; #ifdef DEBUG_LZC if(pLzcState->debug) { DBUG(( "clear\n" )); } #endif return TRUE; /* clear the table */ } return FALSE; /* don't clear the table */ } #endif static CONST UCHAR gNu_rmask[9] = {0x00, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f, 0xff}; static void Nu_LZC_putcode(LZCState* pLzcState, INTCODE code, register int bits) { /*static int oldbits = 0;*/ /*static UCHAR outbuf[MAXBITS];*/ register UCHAR *buf; register int shift; if (bits != pLzcState->oldbits) { if (bits == 0) { /* bits == 0 means EOF, write the rest of the buffer. */ if (pLzcState->offset > 0) { fwrite(pLzcState->outbuf,1,(pLzcState->offset +7) >> 3, pLzcState->outfp); pLzcState->bytes_out += ((pLzcState->offset +7) >> 3); } pLzcState->offset = 0; pLzcState->oldbits = 0; fflush(pLzcState->outfp); return; } else { /* Change the code size. We must write the whole buffer, * because the expand side won't discover the size change * until after it has read a buffer full. */ if (pLzcState->offset > 0) { fwrite(pLzcState->outbuf, 1, pLzcState->oldbits, pLzcState->outfp); pLzcState->bytes_out += pLzcState->oldbits; pLzcState->offset = 0; } pLzcState->oldbits = bits; #ifdef DEBUG_LZC if ( pLzcState->debug ) { DBUG(( "\nChange to %d bits\n", bits )); } #endif /* DEBUG_LZC */ } } /* Get to the first byte. */ buf = pLzcState->outbuf + ((shift = pLzcState->offset) >> 3); if ((shift &= 7) != 0) { *(buf) |= (*buf & gNu_rmask[shift]) | (UCHAR)(code << shift); *(++buf) = (UCHAR)(code >> (8 - shift)); if (bits + shift > 16) *(++buf) = (UCHAR)(code >> (16 - shift)); } else { /* Special case for fast execution */ *(buf) = (UCHAR)code; *(++buf) = (UCHAR)(code >> 8); } if ((pLzcState->offset += bits) == (bits << 3)) { pLzcState->bytes_out += bits; fwrite(pLzcState->outbuf,1,bits,pLzcState->outfp); pLzcState->offset = 0; } return; } #define kNuLZCEOF (-1) /* * Get the next byte from the input straw. Also updates the CRC * if "doCalcCRC" is set to true. * * Returns kNuLZCEOF as the value when we're out of data. */ static NuError Nu_LZCGetcCRC(LZCState* pLzcState, int* pSym) { NuError err; uchar c; if (!pLzcState->uncompRemaining) { *pSym = kNuLZCEOF; return kNuErrNone; } err = Nu_StrawRead(pLzcState->pArchive, pLzcState->pStraw, &c, 1); if (err == kNuErrNone) { if (pLzcState->doCalcCRC) pLzcState->crc = Nu_CalcCRC16(pLzcState->crc, &c, 1); *pSym = c; pLzcState->uncompRemaining--; } return err; } /* * compress stdin to stdout */ static void Nu_LZC_compress(LZCState* pLzcState, ulong* pDstLen) { int c,adjbits; register HASH hash; register INTCODE code; HASH hashf[256]; Assert(pLzcState->outfp != nil); pLzcState->maxcode = Maxcode(pLzcState->maxbits); pLzcState->hashsize = Hashsize(pLzcState->maxbits); #ifdef COMP40 /* Only needed for adaptive reset */ pLzcState->checkpoint = CHECK_GAP; pLzcState->ratio = 0; #endif adjbits = pLzcState->maxbits -10; for (c = 256; --c >= 0; ){ hashf[c] = ((( c &0x7) << 7) ^ c) << adjbits; } pLzcState->exit_stat = OK; if (Nu_LZC_alloc_tables(pLzcState, pLzcState->maxcode, pLzcState->hashsize)) /* exit_stat already set */ return; init_tables(); #if 0 /* if not zcat or filter */ if(is_list && !zcat_flg) { /* Open output file */ if (freopen(ofname, WRITE_FILE_TYPE, pLzcState->outfp) == NULL) { pLzcState->exit_stat = NOTOPENED; return; } if (!quiet) fprintf(stderr, "%s: ",ifname); setvbuf(Xstdout,zbuf,_IOFBF,ZBUFSIZE); } #endif /* * Check the input stream for previously seen strings. We keep * adding characters to the previously seen prefix string until we * get a character which forms a new (unseen) string. We then send * the code for the previously seen prefix string, and add the new * string to our tables. The check for previous strings is done by * hashing. If the code for the hash value is unused, then we have * a new string. If the code is used, we check to see if the prefix * and suffix values match the current input; if so, we have found * a previously seen string. Otherwise, we have a hash collision, * and we try secondary hash probes until we either find the current * string, or we find an unused entry (which indicates a new string). */ if (1 /*!nomagic*/) { putc(gNu_magic_header[0], pLzcState->outfp); putc(gNu_magic_header[1], pLzcState->outfp); putc((char)(pLzcState->maxbits | pLzcState->block_compress), pLzcState->outfp); if(ferror(pLzcState->outfp)){ /* check it on entry */ pLzcState->exit_stat = WRITEERR; return; } pLzcState->bytes_out = 3L; /* includes 3-byte header mojo */ } else pLzcState->bytes_out = 0L; /* no 3-byte header mojo */ pLzcState->in_count = 1L; pLzcState->offset = 0; pLzcState->exit_stat = Nu_LZCGetcCRC(pLzcState, &c); if (pLzcState->exit_stat != kNuErrNone) return; pLzcState->prefxcode = (INTCODE)c; while (1) { pLzcState->exit_stat = Nu_LZCGetcCRC(pLzcState, &c); if (pLzcState->exit_stat != kNuErrNone) return; if (c == kNuLZCEOF) break; pLzcState->in_count++; hash = pLzcState->prefxcode ^ hashf[c]; /* I need to check that my hash value is within range * because my 16-bit hash table is smaller than 64k. */ if (hash >= pLzcState->hashsize) hash -= pLzcState->hashsize; if ((code = (INTCODE)probe(hash)) != UNUSED) { if (suffix(code) != (char)c || (INTCODE)prefix(code) != pLzcState->prefxcode) { /* hashdelta is subtracted from hash on each iteration of * the following hash table search loop. I compute it once * here to remove it from the loop. */ HASH hashdelta = (0x120 - c) << (adjbits); do { /* rehash and keep looking */ Assert(code >= FIRSTFREE && code <= pLzcState->maxcode); if (hash >= hashdelta) hash -= hashdelta; else hash += (pLzcState->hashsize - hashdelta); Assert(hash < pLzcState->hashsize); if ((code = (INTCODE)probe(hash)) == UNUSED) goto newcode; } while (suffix(code) != (char)c || (INTCODE)prefix(code) != pLzcState->prefxcode); } pLzcState->prefxcode = code; } else { newcode: { Nu_LZC_putcode(pLzcState, pLzcState->prefxcode, pLzcState->bits); code = pLzcState->nextfree; Assert(hash < pLzcState->hashsize); Assert(code >= FIRSTFREE); Assert(code <= pLzcState->maxcode + 1); if (code <= pLzcState->maxcode) { probe(hash) = (CODE)code; prefix(code) = (CODE)pLzcState->prefxcode; suffix(code) = (char)c; if (code > pLzcState->highcode) { pLzcState->highcode += code; ++pLzcState->bits; } pLzcState->nextfree = code + 1; } #ifdef COMP40 else if (pLzcState->in_count >= pLzcState->checkpoint && pLzcState->block_compress ) { if (Nu_LZC_cl_block(pLzcState)){ #else else if (pLzcState->block_compress){ #endif Nu_LZC_putcode(pLzcState, (INTCODE)c, pLzcState->bits); Nu_LZC_putcode(pLzcState, CLEAR, pLzcState->bits); init_tables(); pLzcState->exit_stat = Nu_LZCGetcCRC(pLzcState, &c); if (pLzcState->exit_stat != kNuErrNone) return; if (c == kNuLZCEOF) break; pLzcState->in_count++; #ifdef COMP40 } #endif } pLzcState->prefxcode = (INTCODE)c; } } } Nu_LZC_putcode(pLzcState, pLzcState->prefxcode, pLzcState->bits); Nu_LZC_putcode(pLzcState, CLEAR, 0); /* * Print out stats on stderr */ if(1 /*zcat_flg == 0 && !quiet*/) { #ifdef DEBUG_LZC DBUG(( "%ld chars in, (%ld bytes) out, compression factor: ", pLzcState->in_count, pLzcState->bytes_out )); Nu_prratio( pLzcState->in_count, pLzcState->bytes_out ); DBUG(( "\n")); DBUG(( "\tCompression as in compact: " )); Nu_prratio( pLzcState->in_count-pLzcState->bytes_out, pLzcState->in_count ); DBUG(( "\n")); DBUG(( "\tLargest code (of last block) was %d (%d bits)\n", pLzcState->prefxcode - 1, pLzcState->bits )); #else DBUG(( "Compression: " )); Nu_prratio( pLzcState->in_count-pLzcState->bytes_out, pLzcState->in_count ); #endif /* DEBUG_LZC */ } if(pLzcState->bytes_out > pLzcState->in_count) /* if no savings */ pLzcState->exit_stat = NOSAVING; *pDstLen = pLzcState->bytes_out; return ; } /* * NufxLib interface to LZC compression. */ static NuError Nu_CompressLZC(NuArchive* pArchive, NuStraw* pStraw, FILE* fp, ulong srcLen, ulong* pDstLen, ushort* pCrc, int maxbits) { NuError err = kNuErrNone; LZCState lzcState; memset(&lzcState, 0, sizeof(lzcState)); lzcState.pArchive = pArchive; lzcState.pStraw = pStraw; lzcState.outfp = fp; lzcState.uncompRemaining = srcLen; if (pCrc == nil) { lzcState.doCalcCRC = false; } else { lzcState.doCalcCRC = true; lzcState.crc = *pCrc; } lzcState.maxbits = maxbits; lzcState.block_compress = BLOCK_MASK; /* enabled */ Nu_LZC_compress(&lzcState, pDstLen); err = lzcState.exit_stat; DBUG(("+++ LZC_compress returned with %d\n", err)); #if (SPLIT_HT) free_array(CODE,lzcState.ht[1], 0); free_array(CODE,lzcState.ht[0], 0); #else free_array(CODE,lzcState.ht, 0); #endif #if (SPLIT_PFX) free_array(CODE,lzcState.pfx[1], 128); free_array(CODE,lzcState.pfx[0], 128); #else free_array(CODE,lzcState.pfx, 256); #endif free_array(char,lzcState.sfx, 256); if (pCrc != nil) *pCrc = lzcState.crc; return err; } NuError Nu_CompressLZC12(NuArchive* pArchive, NuStraw* pStraw, FILE* fp, ulong srcLen, ulong* pDstLen, ushort* pCrc) { return Nu_CompressLZC(pArchive, pStraw, fp, srcLen, pDstLen, pCrc, 12); } NuError Nu_CompressLZC16(NuArchive* pArchive, NuStraw* pStraw, FILE* fp, ulong srcLen, ulong* pDstLen, ushort* pCrc) { return Nu_CompressLZC(pArchive, pStraw, fp, srcLen, pDstLen, pCrc, 16); } /* * =========================================================================== * Expansion * =========================================================================== */ /* * Write the next byte to the output funnel. Also updates the CRC * if "doCalcCRC" is set to true. * * Returns kNuLZCEOF as the value when we're out of data. */ static NuError Nu_LZCPutcCRC(LZCState* pLzcState, char c) { NuError err; err = Nu_FunnelWrite(pLzcState->pArchive, pLzcState->pFunnel, &c, 1); if (pLzcState->doCalcCRC) pLzcState->crc = Nu_CalcCRC16(pLzcState->crc, &c, 1); return err; } static int Nu_LZC_nextcode(LZCState* pLzcState, INTCODE* codeptr) /* Get the next code from input and put it in *codeptr. * Return (TRUE) on success, or return (FALSE) on end-of-file. * Adapted from COMPRESS V4.0. */ { /*static int prevbits = 0;*/ register INTCODE code; /*static int size;*/ /*static UCHAR inbuf[MAXBITS];*/ register int shift; UCHAR *bp; /* If the next entry is a different bit-size than the preceeding one * then we must adjust the size and scrap the old buffer. */ if (pLzcState->prevbits != pLzcState->bits) { pLzcState->prevbits = pLzcState->bits; pLzcState->size = 0; } /* If we can't read another code from the buffer, then refill it. */ shift = pLzcState->offset; if (pLzcState->size - shift < pLzcState->bits) { /* Read more input and convert size from # of bytes to # of bits */ long getSize; getSize = pLzcState->bits; if (getSize > pLzcState->compRemaining) getSize = pLzcState->compRemaining; if (!getSize) /* act like EOF */ return FALSE; pLzcState->size = fread(pLzcState->inbuf, 1, getSize, pLzcState->infp) << 3; if (pLzcState->size <= 0 || ferror(pLzcState->infp)) return(FALSE); pLzcState->compRemaining -= getSize; pLzcState->offset = shift = 0; } /* Get to the first byte. */ bp = pLzcState->inbuf + (shift >> 3); /* Get first part (low order bits) */ code = (*bp++ >> (shift &= 7)); /* high order bits. */ code |= *bp++ << (shift = 8 - shift); if ((shift += 8) < pLzcState->bits) code |= *bp << shift; *codeptr = code & pLzcState->highcode; pLzcState->offset += pLzcState->bits; return (TRUE); } static void Nu_LZC_decompress(LZCState* pLzcState, ulong compressedLen) { NuArchive* pArchive = pLzcState->pArchive; register int i; register INTCODE code; char sufxchar = 0; INTCODE savecode; FLAG fulltable = FALSE, cleartable; /*static*/ char *token= NULL; /* String buffer to build token */ /*static*/ int maxtoklen = MAXTOKLEN; int flags; Assert(pLzcState->infp != nil); pLzcState->exit_stat = OK; if (compressedLen < 3) { /* not long enough to be valid! */ pLzcState->exit_stat = kNuErrBadData; Nu_ReportError(NU_BLOB, pLzcState->exit_stat, "thread too short to be valid LZC"); return; } pLzcState->compRemaining = compressedLen; /* * This comes out of "compress.c" rather than "compapi.c". */ if ((getc(pLzcState->infp)!=(gNu_magic_header[0] & 0xFF)) || (getc(pLzcState->infp)!=(gNu_magic_header[1] & 0xFF))) { DBUG(("not in compressed format\n")); pLzcState->exit_stat = kNuErrBadData; return; } flags = getc(pLzcState->infp); /* set -b from file */ pLzcState->block_compress = flags & BLOCK_MASK; pLzcState->maxbits = flags & BIT_MASK; if(pLzcState->maxbits > MAXBITS) { DBUG(("compressed with %d bits, can only handle %d bits\n", pLzcState->maxbits, MAXBITS)); pLzcState->exit_stat = kNuErrBadData; return; } pLzcState->compRemaining -= 3; /* Initialze the token buffer. */ token = (char*)Nu_Malloc(pArchive, maxtoklen); if (token == NULL) { pLzcState->exit_stat = NOMEM; return; } if (Nu_LZC_alloc_tables(pLzcState, pLzcState->maxcode = ~(~(INTCODE)0 << pLzcState->maxbits),0)) /* exit_stat already set */ return; #if 0 /* if not zcat or filter */ if(is_list && !zcat_flg) { /* Open output file */ if (freopen(ofname, WRITE_FILE_TYPE, stdout) == NULL) { pLzcState->exit_stat = NOTOPENED; return; } if (!quiet) fprintf(stderr, "%s: ",ifname); setvbuf(stdout,xbuf,_IOFBF,XBUFSIZE); } #endif cleartable = TRUE; savecode = CLEAR; pLzcState->offset = 0; do { if ((code = savecode) == CLEAR && cleartable) { pLzcState->highcode = ~(~(INTCODE)0 << (pLzcState->bits = INITBITS)); fulltable = FALSE; pLzcState->nextfree = (cleartable = pLzcState->block_compress) == FALSE ? 256 : FIRSTFREE; if (!Nu_LZC_nextcode(pLzcState, &pLzcState->prefxcode)) break; /*putc((*/sufxchar = (char)pLzcState->prefxcode/*), stdout)*/; pLzcState->exit_stat = Nu_LZCPutcCRC(pLzcState, sufxchar); if (pLzcState->exit_stat != kNuErrNone) return; continue; } i = 0; if (code >= pLzcState->nextfree && !fulltable) { if (code != pLzcState->nextfree){ DBUG(("ERROR: code (0x%x) != nextfree (0x%x)\n", code, pLzcState->nextfree)); pLzcState->exit_stat = CODEBAD; return ; /* Non-existant code */ } /* Special case for sequence KwKwK (see text of article) */ code = pLzcState->prefxcode; token[i++] = sufxchar; } /* Build the token string in reverse order by chasing down through * successive prefix tokens of the current token. Then output it. */ while (code >= 256) { #ifdef DEBUG_LZC /* These are checks to ease paranoia. Prefix codes must decrease * monotonically, otherwise we must have corrupt tables. We can * also check that we haven't overrun the token buffer. */ if (code <= (INTCODE)prefix(code)){ pLzcState->exit_stat= TABLEBAD; return; } #endif if (i >= maxtoklen) { maxtoklen *= 2; /* double the size of the token buffer */ if ((token = Nu_Realloc(pArchive, token, maxtoklen)) == NULL) { pLzcState->exit_stat = TOKTOOBIG; return; } } token[i++] = suffix(code); code = (INTCODE)prefix(code); } /*putc(*/sufxchar = (char)code/*, stdout)*/; pLzcState->exit_stat = Nu_LZCPutcCRC(pLzcState, sufxchar); while (--i >= 0) { /*putc(token[i], stdout);*/ pLzcState->exit_stat = Nu_LZCPutcCRC(pLzcState, token[i]); } if (pLzcState->exit_stat != kNuErrNone) return; /* If table isn't full, add new token code to the table with * codeprefix and codesuffix, and remember current code. */ if (!fulltable) { code = pLzcState->nextfree; Assert(256 <= code && code <= pLzcState->maxcode); prefix(code) = (CODE)pLzcState->prefxcode; suffix(code) = sufxchar; pLzcState->prefxcode = savecode; if (code++ == pLzcState->highcode) { if (pLzcState->highcode >= pLzcState->maxcode) { fulltable = TRUE; --code; } else { ++pLzcState->bits; pLzcState->highcode += code; /* nextfree == highcode + 1 */ } } pLzcState->nextfree = code; } } while (Nu_LZC_nextcode(pLzcState, &savecode)); pLzcState->exit_stat = (ferror(pLzcState->infp))? READERR : OK; Nu_Free(pArchive, token); return ; } /* * NufxLib interface to LZC expansion. */ NuError Nu_ExpandLZC(NuArchive* pArchive, const NuRecord* pRecord, const NuThread* pThread, FILE* infp, NuFunnel* pFunnel, ushort* pCrc) { NuError err = kNuErrNone; LZCState lzcState; memset(&lzcState, 0, sizeof(lzcState)); lzcState.pArchive = pArchive; lzcState.infp = infp; lzcState.pFunnel = pFunnel; if (pCrc == nil) { lzcState.doCalcCRC = false; } else { lzcState.doCalcCRC = true; lzcState.crc = *pCrc; } Nu_LZC_decompress(&lzcState, pThread->thCompThreadEOF); err = lzcState.exit_stat; DBUG(("+++ LZC_decompress returned with %d\n", err)); #if (SPLIT_HT) free_array(CODE,lzcState.ht[1], 0); free_array(CODE,lzcState.ht[0], 0); #else free_array(CODE,lzcState.ht, 0); #endif #if (SPLIT_PFX) free_array(CODE,lzcState.pfx[1], 128); free_array(CODE,lzcState.pfx[0], 128); #else free_array(CODE,lzcState.pfx, 256); #endif free_array(char,lzcState.sfx, 256); if (pCrc != nil) *pCrc = lzcState.crc; return err; } #endif /*ENABLE_LZC*/