/*ProfiPacket - packet radio terminal program Copyright (C) 1999 Alexander Feigl This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA Author: Alexander Feigl Burachstraße 51 D-88250 Weingarten Mail : Alexander.Feigl@gmx.de */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #ifdef __GNUC__ #define _storage_text_ __attribute__ ((section(".text"))) #else #define _storage_text_ #endif #include #define EOF -1 #include #include #include #include #include #ifdef __GNUC__ #include #include #endif #define maxcompfilesize 10000000 /* this is important */ /*----------------------------------------------------------------------*/ /* */ /* LZSS ENCODING */ /* */ /*----------------------------------------------------------------------*/ #define N4K 4096 /* buffer size (original 4096) */ #define N2K 2048 #define F 60 /* pre-sence buffer size */ #define THRESHOLD 2 #define NILE N2K /* term of tree */ #define N_CHAR (256 - THRESHOLD + F) /* {code : 0 .. N_CHAR-1} */ #define T (N_CHAR * 2 - 1) /* size of table */ #define R (T - 1) /* root position */ #define MAX_FREQ 0x8000 /* tree update timing from frequency */ typedef unsigned char uchar; typedef const unsigned char cuchar; extern unsigned int *freq; extern int *prnt; extern int *son; extern unsigned getbuf; extern uchar getlen; extern void *DOSBase; extern void *SysBase; extern BPTR infile,outfile; extern int in_memory, out_memory; extern unsigned long int textsize, codesize; extern char *srcbuf, *destbuf; extern char *srcbufptr, *destbufptr; extern long srclen, destlen; extern long srcbuflen, destbuflen; extern unsigned char *text_buf; extern unsigned long int match_position,match_length; extern int *lson,*rson,*dad; extern unsigned char *same; extern unsigned putbuf; extern unsigned char putlen; /*static unsigned char text_buf[N4K + F - 1]; static unsigned int match_position, match_length; static int lson[N4K + 1], rson[N4K + 1 + N4K], dad[N4K + 1]; static unsigned char same[N4K + 1]; */ int GetBuffers(void) { text_buf=AllocVec(sizeof(char)*(N4K+F-1),1); if (text_buf==NULL) return(FALSE); lson=AllocVec(sizeof(int)*(N4K+1),1); if (lson==NULL) { FreeVec(text_buf); return(FALSE); } rson=AllocVec(sizeof(int)*(N4K+N4K+1),1); if (rson==NULL) { FreeVec(lson); FreeVec(text_buf); return(FALSE); } dad=AllocVec(sizeof(int)*(N4K+1),1); if (dad==NULL) { FreeVec(rson); FreeVec(lson); FreeVec(text_buf); return(FALSE); } same=AllocVec(sizeof(int)*(N4K+1),1); if (same==NULL) { FreeVec(dad); FreeVec(rson); FreeVec(lson); FreeVec(text_buf); return(FALSE); } freq=AllocVec(sizeof(unsigned)*(T+1),1); if (freq==NULL) { FreeVec(same); FreeVec(dad); FreeVec(rson); FreeVec(lson); FreeVec(text_buf); return(FALSE); } prnt=AllocVec(sizeof(int)*(T+N_CHAR),1); if (prnt==NULL) { FreeVec(freq); FreeVec(same); FreeVec(dad); FreeVec(rson); FreeVec(lson); FreeVec(text_buf); } son=AllocVec(sizeof(int)*T,1); if (son==NULL) { FreeVec(prnt); FreeVec(freq); FreeVec(same); FreeVec(dad); FreeVec(rson); FreeVec(lson); FreeVec(text_buf); } putbuf=0; putlen=0; getbuf=0; getlen=0; return(TRUE); } void FreeBuffers(void) { FreeVec(text_buf); FreeVec(lson); FreeVec(rson); FreeVec(dad); FreeVec(same); } static int read_char() { int chr; if (in_memory) { if (srclen < srcbuflen) { chr = *srcbufptr; srcbufptr++; srclen++; return(chr); } else { return(EOF); } } else { return(FGetC(infile)); } } /* read byte from input, ignore EOF */ static unsigned int read_char1(int mode,unsigned short *crc) { unsigned int chr; if (in_memory) { if (srclen < srcbuflen) { chr = *srcbufptr; srcbufptr++; srclen++; if (mode) crcfbb(chr,crc); return(chr); } else { return(0); } } else { if ((chr = FGetC(infile)) ==-1) { return(0); } if (mode) crcfbb(chr,crc); return(chr); } } /* write byte to output */ static int wri_char(int chr,int mode,unsigned short *crc) { if (out_memory) { if (destlen < destbuflen) { *destbufptr = (char) chr; if (mode) crcfbb(chr,crc); destbufptr++; destlen++; return((char) chr); } else { return(EOF); } } else { if (mode) crcfbb(chr,crc); return (FPutC(outfile,chr)); } } int getlong(unsigned long *textsize,int mode,unsigned short *crc) { int char1,char2,char3,char4; char1=read_char1(mode,crc); char2=read_char1(mode,crc); char3=read_char1(mode,crc); char4=read_char1(mode,crc); *textsize= (char1&0xff) + (char2&0xff) * 256 + (char3&0xff) * 65536 + (char4&0xff) * 65536 * 256; return(1); } int putlong(unsigned long textsize,int mode,unsigned short *crc) { unsigned long c1,c2,c3,c4; c1= textsize % 256; c2= (textsize/256) % 256; c3= (textsize/65536) % 256; c4= (textsize/(65536*256)) % 256; wri_char(c1,mode,crc); wri_char(c2,mode,crc); wri_char(c3,mode,crc); wri_char(c4,mode,crc); return(1); } /*static int isdigit(unsigned char di) { if ( (di>='0') && (di<=9) ) return(TRUE); return(FALSE); } static void strcpy(unsigned char *s1,unsigned char *s2) { while (*s2!='\0') *(s1++)=*(s2++); } */ static int Tell(BPTR file) { signed long oldptr; oldptr=Seek(file,0,OFFSET_CURRENT); if (oldptr==-1) return(0); return(oldptr); } /* Initialize Tree */ static void InitTree () { register int *p, *e; for (p = (rson + N2K + 1), e = (rson + N4K + N4K); p <= e; ) *p++ = NILE; for (p = dad, e = dad + N4K; p < e; ) *p++ = NILE; } /* Insert to node */ static void InsertNode (int r) { register int p; int cmp; register unsigned char *key; register unsigned int c; register unsigned int i, j; cmp = 1; key = &text_buf[r]; i = key[1] ^ key[2]; i ^= i >> 4; p = N2K + 1 + key[0] + ((i & 0x0f) << 8); rson[r] = lson[r] = NILE; match_length = 0; i = j = 1; for ( ; ; ) { if (cmp >= 0) { if (rson[p] != NILE) { p = rson[p]; j = same[p]; } else { rson[p] = r; dad[r] = p; same[r] = i; return; } } else { if (lson[p] != NILE) { p = lson[p]; j = same[p]; } else { lson[p] = r; dad[r] = p; same[r] = i; return; } } if (i > j) { i = j; cmp = key[i] - text_buf[p + i]; } else if (i == j) { for (; i < F; i++) if ((cmp = key[i] - text_buf[p + i]) != 0) break; } if (i > THRESHOLD) { if (i > match_length) { match_position = ((r - p) & (N2K - 1)) - 1; if ((match_length = i) >= F) break; } else if (i == match_length) { if ((c = ((r - p) & (N2K - 1)) - 1) < match_position) { match_position = c; } } } } same[r] = same[p]; dad[r] = dad[p]; lson[r] = lson[p]; rson[r] = rson[p]; dad[lson[p]] = r; dad[rson[p]] = r; if (rson[dad[p]] == p) rson[dad[p]] = r; else lson[dad[p]] = r; dad[p] = NILE; /* remove p */ } static void link (int n, int p, int q) { register unsigned char *s1, *s2, *s3; if (p >= NILE) { same[q] = 1; return; } s1 = text_buf + p + n; s2 = text_buf + q + n; s3 = text_buf + p + F; while (s1 < s3) { if (*s1++ != *s2++) { same[q] = s1 - 1 - text_buf - p; return; } } same[q] = F; } static void linknode (int p, int q, int r) { int cmp; if ((cmp = same[q] - same[r]) == 0) { link(same[q], p, r); } else if (cmp < 0) { same[r] = same[q]; } } static void DeleteNode (int p) { register int q; if (dad[p] == NILE) return; /* has no linked */ if (rson[p] == NILE) { if ((q = lson[p]) != NILE) linknode(dad[p], p, q); } else if (lson[p] == NILE) { q = rson[p]; linknode(dad[p], p, q); } else { q = lson[p]; if (rson[q] != NILE) { do { q = rson[q]; } while (rson[q] != NILE); if (lson[q] != NILE) linknode(dad[q], q, lson[q]); link(1, q, lson[p]); rson[dad[q]] = lson[q]; dad[lson[q]] = dad[q]; lson[q] = lson[p]; dad[lson[p]] = q; } link(1, dad[p], q); link(1, q, rson[p]); rson[q] = rson[p]; dad[rson[p]] = q; } dad[q] = dad[p]; if (rson[dad[p]] == p) rson[dad[p]] = q; else lson[dad[p]] = q; dad[p] = NILE; } /*----------------------------------------------------------------------*/ /* */ /* HUFFMAN ENCODING */ /* */ /*----------------------------------------------------------------------*/ /* TABLE OF ENCODE/DECODE for upper 6bits position information */ /* for encode */ cuchar _storage_text_ p_len[64] = { 0x03, 0x04, 0x04, 0x04, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08 }; cuchar _storage_text_ p_code[64] = { 0x00, 0x20, 0x30, 0x40, 0x50, 0x58, 0x60, 0x68, 0x70, 0x78, 0x80, 0x88, 0x90, 0x94, 0x98, 0x9C, 0xA0, 0xA4, 0xA8, 0xAC, 0xB0, 0xB4, 0xB8, 0xBC, 0xC0, 0xC2, 0xC4, 0xC6, 0xC8, 0xCA, 0xCC, 0xCE, 0xD0, 0xD2, 0xD4, 0xD6, 0xD8, 0xDA, 0xDC, 0xDE, 0xE0, 0xE2, 0xE4, 0xE6, 0xE8, 0xEA, 0xEC, 0xEE, 0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7, 0xF8, 0xF9, 0xFA, 0xFB, 0xFC, 0xFD, 0xFE, 0xFF }; /* for decode */ cuchar _storage_text_ d_code[256] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x09, 0x09, 0x09, 0x09, 0x09, 0x09, 0x09, 0x09, 0x0A, 0x0A, 0x0A, 0x0A, 0x0A, 0x0A, 0x0A, 0x0A, 0x0B, 0x0B, 0x0B, 0x0B, 0x0B, 0x0B, 0x0B, 0x0B, 0x0C, 0x0C, 0x0C, 0x0C, 0x0D, 0x0D, 0x0D, 0x0D, 0x0E, 0x0E, 0x0E, 0x0E, 0x0F, 0x0F, 0x0F, 0x0F, 0x10, 0x10, 0x10, 0x10, 0x11, 0x11, 0x11, 0x11, 0x12, 0x12, 0x12, 0x12, 0x13, 0x13, 0x13, 0x13, 0x14, 0x14, 0x14, 0x14, 0x15, 0x15, 0x15, 0x15, 0x16, 0x16, 0x16, 0x16, 0x17, 0x17, 0x17, 0x17, 0x18, 0x18, 0x19, 0x19, 0x1A, 0x1A, 0x1B, 0x1B, 0x1C, 0x1C, 0x1D, 0x1D, 0x1E, 0x1E, 0x1F, 0x1F, 0x20, 0x20, 0x21, 0x21, 0x22, 0x22, 0x23, 0x23, 0x24, 0x24, 0x25, 0x25, 0x26, 0x26, 0x27, 0x27, 0x28, 0x28, 0x29, 0x29, 0x2A, 0x2A, 0x2B, 0x2B, 0x2C, 0x2C, 0x2D, 0x2D, 0x2E, 0x2E, 0x2F, 0x2F, 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, 0x3B, 0x3C, 0x3D, 0x3E, 0x3F, }; cuchar _storage_text_ d_len[256] = { 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, }; //static unsigned freq[T + 1]; /* frequency table */ //static int prnt[T + N_CHAR]; /* points to parent node */ //* notes : // prnt[T .. T + N_CHAR - 1] used by // indicates leaf position that corresponding to code */ //static int son[T]; /* points to son node (son[i],son[i+]) */ //static unsigned getbuf = 0; //static uchar getlen = 0; /* get one bit */ /* returning in Bit 0 */ static int GetBit (int mode,unsigned short *crc) { register unsigned int dx = getbuf; register unsigned int c; if (getlen <= 8) { c = read_char1(mode,crc); dx |= c << (8 - getlen); getlen += 8; } getbuf = dx << 1; getlen--; return (dx & 0x8000) ? 1 : 0; } /* get one byte */ /* returning in Bit7...0 */ static int GetByte (int mode,unsigned short *crc) { register unsigned int dx = getbuf; register unsigned c; if (getlen <= 8) { c = read_char1(mode,crc); dx |= c << (8 - getlen); getlen += 8; } getbuf = dx << 8; getlen -= 8; return (dx >> 8) & 0xff; } const static _storage_text_ int getn_mask[17] = { 0x0000, 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff, 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x0fff, 0xffff }; const static _storage_text_ int getn_shift[17] = { 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0 }; /* get N bit */ /* returning in Bit(N-1)...Bit 0 */ static int GetNBits (unsigned int n,int mode,unsigned short *crc) { register unsigned int dx = getbuf; register unsigned int c; if (getlen <= 8) { c = read_char1(mode,crc); dx |= c << (8 - getlen); getlen += 8; } getbuf = dx << n; getlen -= n; return (dx >> getn_shift[n]) & getn_mask[n]; } /* output C bits */ static int Putcode (int l, unsigned int c,int mode,unsigned short *crc) { int len = putlen; register unsigned int b = putbuf; b |= c >> len; if ((len += l) >= 8) { if (wri_char(b >> 8,mode,crc) == EOF) return(1); if ((len -= 8) >= 8) { if (wri_char(b,mode,crc) == EOF) return(1); codesize += 2; len -= 8; b = c << (l - len); } else { b <<= 8; codesize++; } } putbuf = b; putlen = len; return(0); } /* Initialize tree */ static void StartHuff () { register int i, j; for (i = 0; i < N_CHAR; i++) { freq[i] = 1; son[i] = i + T; prnt[i + T] = i; } i = 0; j = N_CHAR; while (j <= R) { freq[j] = freq[i] + freq[i + 1]; son[j] = i; prnt[i] = prnt[i + 1] = j; i += 2; j++; } freq[T] = 0xffff; prnt[R] = 0; putlen = getlen = 0; putbuf = getbuf = 0; } /* reconstruct tree */ static void reconst () { register int i, j, k; register unsigned f; /* correct leaf node into of first half, and set these freqency to (freq+1)/2 */ j = 0; for (i = 0; i < T; i++) { if (son[i] >= T) { freq[j] = (freq[i] + 1) / 2; son[j] = son[i]; j++; } } /* build tree. Link sons first */ for (i = 0, j = N_CHAR; j < T; i += 2, j++) { k = i + 1; f = freq[j] = freq[i] + freq[k]; for (k = j - 1; f < freq[k]; k--); k++; { register unsigned *p, *e; for (p = &freq[j], e = &freq[k]; p > e; p--) p[0] = p[-1]; freq[k] = f; } { register int *p, *e; for (p = &son[j], e = &son[k]; p > e; p--) p[0] = p[-1]; son[k] = i; } } /* link parents */ for (i = 0; i < T; i++) { if ((k = son[i]) >= T) { prnt[k] = i; } else { prnt[k] = prnt[k + 1] = i; } } } /* update given code's frequency, and update tree */ static void update (int c) { register unsigned *p; register int i, j, k, l; if (freq[R] == MAX_FREQ) { reconst(); } c = prnt[c + T]; do { k = ++freq[c]; /* swap nodes when become wrong frequency order. */ if (k > freq[l = c + 1]) { for (p = freq+l+1; k > *p++; ) ; l = p - freq - 2; freq[c] = p[-2]; p[-2] = k; i = son[c]; prnt[i] = l; if (i < T) prnt[i + 1] = l; j = son[l]; son[l] = i; prnt[j] = c; if (j < T) prnt[j + 1] = c; son[c] = j; c = l; } } while ((c = prnt[c]) != 0); /* loop until reach to root */ } /* static unsigned code, len; */ static int EncodeChar (unsigned c,int mode,unsigned short *crc) { register int *p; register unsigned long i; register int j, k; i = 0; j = 0; p = prnt; k = p[c + T]; /* trace links from leaf node to root */ do { i >>= 1; /* if node index is odd, trace larger of sons */ if (k & 1) i += 0x80000000; j++; } while ((k = p[k]) != R) ; if (j > 16) { if (Putcode(16, (unsigned int)(i >> 16),mode,crc)) return(1); if (Putcode(j - 16, (unsigned int)i,mode,crc)) return(1); } else { if (Putcode(j, (unsigned int)(i >> 16),mode,crc)) return(1); } /* code = i; */ /* len = j; */ update(c); return(0); } static int EncodePosition (unsigned c,int mode,unsigned short *crc) { unsigned i; /* output upper 6bit from table */ i = c >> 6; if (Putcode((int)(p_len[i]), (unsigned int)(p_code[i]) << 8,mode,crc)) return(1); /* output lower 6 bit */ if (Putcode(6, (unsigned int)(c & 0x3f) << 10,mode,crc)) return(1); return(0); } static int EncodeEnd(int mode,unsigned short *crc) { if (putlen) { if (wri_char(putbuf >> 8,mode,crc) == EOF) return(1); codesize++; } return(0); } static int DecodeChar (int mode,unsigned short *crc) { register unsigned c; c = son[R]; /* trace from root to leaf, got bit is 0 to small(son[]), 1 to large (son[]+1) son node */ while (c < T) { c += GetBit(mode,crc); c = son[c]; } c -= T; update(c); return c; } static int DecodePosition (int mode,unsigned short *crc) { unsigned i, j, c; /* decode upper 6bit from table */ i = GetByte(mode,crc); c = (unsigned)d_code[i] << 6; j = d_len[i]; /* get lower 6bit */ j -= 2; return c | (((i << j) | GetNBits (j,mode,crc)) & 0x3f); } /* compression */ static int Encode (int mode,unsigned short *crc) { register int i, c, len, r, s, last_match_length; textsize = 0; StartHuff(); InitTree(); s = 0; r = N4K - F; for (i = s; i < r; i++) text_buf[i] = ' '; r = N2K - F; /* this is important! */ for (len = 0; len < F && (c = read_char()) != EOF; len++) text_buf[r + len] = c; textsize = len; for (i = 1; i <= F; i++) InsertNode(r - i); InsertNode(r); do { if (match_length > len) match_length = len; if (match_length <= THRESHOLD) { match_length = 1; if (EncodeChar(text_buf[r],mode,crc)) return(1); } else { if (EncodeChar(255 - THRESHOLD + match_length,mode,crc)) return(1); if (EncodePosition(match_position,mode,crc)) return(1); } last_match_length = match_length; for (i = 0; i < last_match_length && (c = read_char()) != EOF; i++) { DeleteNode(s); text_buf[s] = c; if (s < F - 1) text_buf[s + N2K] = c; s = (s + 1) & (N2K - 1); r = (r + 1) & (N2K - 1); InsertNode(r); } textsize += i; while (i++ < last_match_length) { DeleteNode(s); s = (s + 1) & (N2K - 1); r = (r + 1) & (N2K - 1); if (--len) InsertNode(r); } } while (len > 0); if (EncodeEnd(mode,crc)) return(1); return(0); } static int Decode(unsigned long int textsize, int mode,unsigned short *fbb_check) /* recover */ { register int i, j, k, r, c; register unsigned long int count; StartHuff(); r = N4K - F; for (i = 0; i < r; i++) text_buf[i] = ' '; for (count = 0; count < textsize; ) { c = DecodeChar(mode,fbb_check); if (c < 256) { if (wri_char(c,0,NULL) == EOF) return(1); text_buf[r++] = c; r &= (N4K - 1); count++; } else { i = (r - DecodePosition(mode,fbb_check) - 1) & (N4K - 1); j = c - 255 + THRESHOLD; for (k = 0; k < j; k++) { c = text_buf[(i + k) & (N4K - 1)]; if (wri_char(c,0,NULL) == EOF) return(1); text_buf[r++] = c; r &= (N4K - 1); count++; } } } return(0); } static void init_huf() { textsize = 0; codesize = 0; getbuf = 0; getlen = 0; putbuf = 0; putlen = 0; } int enchuf(char *inputfile,char *outputfile,int mode,char *title) { int error; char *inputfptr; unsigned short fbb_check; inputfptr = inputfile; in_memory = 0; out_memory = 0; fbb_check=0; if (mode==2) { char *sptr; sptr=title; while (*sptr!='\0') { crcfbb(*(sptr++),&fbb_check); } } init_huf(); if ((infile = Open(inputfptr,MODE_OLDFILE)) == NULL) { return(1); } if ((outfile = Open(outputfile,MODE_NEWFILE)) == NULL) { Close(infile); return(1); } error = 0; Seek(infile, 0L, OFFSET_END); textsize = Tell(infile); if (mode) { wri_char(0,0,NULL); wri_char(0,0,NULL); } if (!putlong(textsize,mode,&fbb_check)) { error = 1; } if (!error) { if (textsize == 0) error = 1; if (!error) { Seek(infile,0,OFFSET_BEGINNING); if (Encode(mode,&fbb_check)) error = 1; if ( (!error) && (mode) ) { unsigned char c1,c2; Seek(outfile,0,OFFSET_BEGINNING); c1=fbb_check & 0xff; c2=(fbb_check >> 8) & 0xff; wri_char(c1,0,NULL); wri_char(c2,0,NULL); } } } Close(infile); Close(outfile); return(error); } int dechuf(char *inputfile,char *outputfile,int mode,char *title) { int error; char *outputfptr; unsigned short fbb_check; unsigned short fbb_check1; fbb_check=0;fbb_check1=0; if (mode==2) { char *sptr; sptr=title; while (*sptr!='\0') { crcfbb(*(sptr++),&fbb_check); } } outputfptr = outputfile; in_memory = 0; out_memory = 0; init_huf(); if ((infile = Open(inputfile,MODE_OLDFILE)) == NULL) { return(1); } if ((outfile = Open(outputfptr,MODE_NEWFILE)) == NULL) { Close(infile); return(1); } if (mode) { unsigned char c1,c2; c1=read_char1(0,NULL); c2=read_char1(0,NULL); fbb_check1= ( ((unsigned long) c1) & 0xff) + ( ((unsigned long) c2) & 0xff) *256; } error = 0; { unsigned long txsize; if (!getlong(&txsize,mode,&fbb_check)) error=1; textsize=txsize; } if (!error) { if (textsize == 0) error = 1; if (!error) { if (textsize > maxcompfilesize) error = 1; if (!error) { if (Decode(textsize,mode,&fbb_check)) error = 1; if (mode) { if (fbb_check!=fbb_check1) error=2; } } } } Close(infile); Close(outfile); return(error); }