/************************************************************** lzhuf.c written by Haruyasu Yoshizaki 11/20/1988 some minor changes 4/6/1989 comments translated by Haruhiko Okumura 4/7/1989 reinserted with modifications into 'lharc.c' by J. Moeller 1/30/1990 **************************************************************/ #define _hufst_ #ifdef _hufst_ #define from extern #else #define from #endif #ifndef __TOS__ #error Please try assembling 'lzhuf.asm'! #endif #include #include #include #include #define RDERR 13 #define WTERR 14 #define MAXBLK 64 extern FILE *infile, *outfile; extern char *infname, *outfname; extern long textsize, codesize; extern unsigned crc, crctbl []; extern unsigned blkcnt; extern unsigned char flg_n; extern long blocksize; extern void error (int errcode, char *p); #define setcrc(ch) (crc = (crc >> 8) ^ crctbl [(crc ^ (ch)) & 0xff]) #ifndef _hufst_ int crc_getc (register FILE *stream) { register int ch; if ((ch = getc (stream)) != EOF) setcrc (ch); return ch; } #else extern int crc_getc(register FILE *stream); #endif /********** LZSS compression **********/ #define N 4096 /* buffer size */ #define F 60 /* lookahead buffer size */ #define THRESHOLD 2 #define NIL N /* leaf of tree */ #define FOLD 18 /* upper limit for match_length */ from unsigned char text_buf[N + F - 1]; from int match_position, match_length, lson[N + 1], rson[N + 257], dad[N + 1]; void InitTree(void) /* initialize trees */ { register int i, *rsonp, *dadp; rsonp=&rson[N+1]; for (i = N + 1; i <= N + 256; i++) *rsonp++ = 2*NIL; /* root */ dadp=dad; for (i = 0; i < N; i++) *dadp++ = 2*NIL; /* node */ } #ifndef _hufst_ void InsertNode(int r) /* insert to tree */ { register int i, p, cmp; unsigned char *key; unsigned c; cmp = 1; key = &text_buf[r]; p = N + 1 + key[0]; rson[r] = lson[r] = NIL; match_length = 0; for ( ; ; ) { if (cmp >= 0) { if (rson[p] != NIL) p = rson[p]; else { rson[p] = r; dad[r] = p; return; } } else { if (lson[p] != NIL) p = lson[p]; else { lson[p] = r; dad[r] = p; return; } } for (i = 1; i < F; i++) if ((cmp = key[i] - text_buf[p + i]) != 0) break; if (i > THRESHOLD) { if (i > match_length) { match_position = ((r - p) & (N - 1)) - 1; if ((match_length = i) >= F) break; } if (i == match_length) { if ((c = ((r - p) & (N - 1)) - 1) < match_position) { match_position = c; } } } } 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] = NIL; /* remove p */ } void DeleteNode(int p) /* remove from tree */ { register int q; if (dad[p] == NIL) return; /* not registered */ if (rson[p] == NIL) q = lson[p]; else if (lson[p] == NIL) q = rson[p]; else { q = lson[p]; if (rson[q] != NIL) { do { q = rson[q]; } while (rson[q] != NIL); rson[dad[q]] = lson[q]; dad[lson[q]] = dad[q]; lson[q] = lson[p]; dad[lson[p]] = q; } 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] = NIL; } #else extern void DeleteNode(int p); #endif /* Huffman coding */ #define N_CHAR (256 - THRESHOLD + F) /* kinds of characters (character code = 0..N_CHAR-1) */ #define T (N_CHAR * 2 - 1) /* size of table */ #define R (T - 1) /* position of root */ #define MAX_FREQ 0x8000 /* updates tree when the */ /* root frequency comes to this value. */ typedef unsigned char uchar; /* table for encoding and decoding the upper 6 bits of position */ /* for encoding */ uchar 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 }; uchar 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 decoding */ uchar 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, }; uchar 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, }; from unsigned freq[T + 1]; /* frequency table */ from int prnt[T + N_CHAR]; /* pointers to parent nodes, except for the */ /* elements [T..T + N_CHAR - 1] which are used to get */ /* the positions of leaves corresponding to the codes. */ from int son[T]; /* pointers to child nodes (son[], son[] + 1) */ from unsigned getbuf; from uchar getlen; #ifndef _hufst_ int GetBit(void) /* get one bit */ { register int i; while (getlen <= 8) { if ((i = getc(infile)) < 0) i = 0; getbuf |= i << (8 - getlen); getlen += 8; } i = getbuf; getbuf <<= 1; getlen--; return (i < 0); } #else int GetBit(void); #endif int GetByte(void) /* get one byte */ { register int i; while (getlen <= 8) { if ((i = getc(infile)) < 0) i = 0; getbuf |= i << (8 - getlen); getlen += 8; } i = getbuf; getbuf <<= 8; getlen -= 8; return (unsigned) i >> 8; } extern unsigned putbuf; extern uchar putlen; #ifndef _hufst_ void Putcode(register int l, register unsigned c) /* output c bits of code */ { putbuf |= c >> putlen; if ((putlen += l) >= 8) { putc(putbuf >> 8, outfile); if ((putlen -= 8) >= 8) { putc(putbuf, outfile); codesize += 2; putlen -= 8; putbuf = c << (l - putlen); } else { putbuf <<= 8; codesize++; } } } #else void Putcode(register int l, register unsigned c); #endif /* initialization of tree */ #ifndef _hufst_ void StartHuff(void) { register int i, j, iT, *sonp, *prntp; register unsigned *freqp; freqp=freq; sonp=son; prntp=&prnt[T]; iT=T; for (i = 0; i < N_CHAR; i++) { *freqp++ = 1; *sonp++ = iT++; *prntp++ = i; } i = 0; j = N_CHAR; freqp=freq; sonp=&son[N_CHAR]; prntp=prnt; while (j <= R) { freq[j] = *freqp++ + *freqp++; *sonp++ = i; *prntp++ = *prntp++ = j; i += 2; j++; } freq[T] = 0xffff; prnt[R] = 0; } /* reconstruction of tree */ void reconst(void) { register int i, j, k; unsigned f, l; /* collect leaf nodes in the first half of the table */ /* and replace the freq by (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++; } } /* begin constructing tree by connecting sons */ 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++; l = (j - k) * 2; memmove(&freq[k + 1], &freq[k], l); freq[k] = f; memmove(&son[k + 1], &son[k], l); son[k] = i; } /* connect prnt */ for (i = 0; i < T; i++) { if ((k = son[i]) >= T) { prnt[k] = i; } else { prnt[k] = prnt[k + 1] = i; } } } /* increment frequency of given code by one, and update tree */ void update(int c) { register int i, j, k, l; if (freq[R] == MAX_FREQ) { reconst(); } c = prnt[c + T]; do { k = ++freq[c]; /* if the order is disturbed, exchange nodes */ if (k > freq[l = c + 1]) { while (k > freq[++l]); l--; freq[c] = freq[l]; freq[l] = 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); /* repeat up to root */ } void EncodeChar(unsigned c) { register unsigned i; register int j, k; i = 0; j = 0; k = prnt[c + T]; /* travel from leaf to root */ do { i >>= 1; /* if node's address is odd-numbered, choose bigger brother node */ if (k & 1) i += 0x8000; j++; } while ((k = prnt[k]) != R); Putcode(j, i); update(c); } void EncodePosition(unsigned c) { register unsigned i; /* output upper 6 bits by table lookup */ i = c >> 6; Putcode(p_len[i], (unsigned)p_code[i] << 8); /* output lower 6 bits verbatim */ Putcode(6, (c & 0x3f) << 10); } #endif void EncodeEnd(void) { if (putlen) { putc(putbuf >> 8, outfile); codesize++; } } #ifndef _hufst_ int DecodeChar(void) { register unsigned c; c = son[R]; /* travel from root to leaf, */ /* choosing the smaller child node (son[]) if the read bit is 0, */ /* the bigger (son[]+1} if 1 */ while (c < T) { c += GetBit(); c = son[c]; } c -= T; update(c); return c; } int DecodePosition(void) { register unsigned i, j, c; /* recover upper 6 bits from table */ i = GetByte(); c = (unsigned)d_code[i] << 6; j = d_len[i]; /* read lower 6 bits verbatim */ j -= 2; while (j--) { i = (i << 1) + GetBit(); } return c | (i & 0x3f); } #else int DecodeChar(void); int DecodePosition(void); extern InsertNode(int r); #endif /* compression */ #ifndef _hufst_ void Encode(void) /* compression */ { register int i, r, s, c; int len, last_match_length; long printcount, printsize; if (textsize == 0) return; putbuf = putlen = 0; printsize = textsize; printcount = printsize < blocksize ? printsize : blocksize; if (blkcnt > MAXBLK) blkcnt = MAXBLK; rewind(infile); textsize = 0; /* rewind and re-read */ StartHuff(); InitTree(); s = 0; r = N - F; for (i = s; i < r; i++) text_buf[i] = ' '; for (len = 0; len < F && (c = crc_getc(infile)) != 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; EncodeChar(text_buf[r]); } else { EncodeChar(255 - THRESHOLD + match_length); EncodePosition(match_position); } last_match_length = match_length; for (i = 0; i < last_match_length && (c = crc_getc(infile)) != EOF; i++) { DeleteNode(s); text_buf[s] = c; if (s < F - 1) text_buf[s + N] = c; s = (s + 1) & (N - 1); r = (r + 1) & (N - 1); InsertNode(r); } if ((textsize += i) >= printcount && i > 0) { if (!flg_n) { if (blkcnt > 0) { putc ('*', stderr); blkcnt--; } printcount += blocksize; if (printcount > printsize) printcount = printsize; } if (ferror (outfile)) break; } while (i++ < last_match_length) { DeleteNode(s); s = (s + 1) & (N - 1); r = (r + 1) & (N - 1); if (--len) InsertNode(r); } } while (len > 0); EncodeEnd(); if (ferror (outfile)) { error (WTERR, outfname); } } #else void Encode(void); #endif #ifndef _hufst_ void Decode(void) /* recover */ { register int i, j, k, r, c; unsigned long int count; long printcount; if (textsize == 0) return; getbuf = getlen = 0; printcount = textsize < blocksize ? textsize : blocksize; if (blkcnt > MAXBLK) blkcnt = MAXBLK; StartHuff(); for (i = 0; i < N - F; i++) text_buf[i] = ' '; r = N - F; for (count = 0; count < textsize; ) { c = DecodeChar(); if (c < 256) { setcrc (c); if (outfile != NULL) putc (c, outfile); text_buf[r++] = c; r &= (N - 1); count++; } else { i = (r - DecodePosition() - 1) & (N - 1); j = c - 255 + THRESHOLD; for (k = 0; k < j; k++) { c = text_buf[(i + k) & (N - 1)]; setcrc (c); if (outfile != NULL) putc (c, outfile); text_buf[r++] = c; r &= (N - 1); count++; } } if (count >= printcount) { if (!flg_n) { if (blkcnt > 0) { putc ('*', stderr); blkcnt--; } printcount += blocksize; if (printcount > textsize) printcount = textsize; } if (outfile != NULL && ferror (outfile)) break; } } if (!flg_n && blkcnt > 0) putc ('*', stderr); if (outfile != NULL && ferror (outfile)) { error (WTERR, outfname); } } #else extern void Decode(void); #endif #define N 4096 /* size of ring buffer */ #define F 18 /* upper limit for match_length */ #define THRESHOLD 2 /* encode string into position and length if match_length is greater than this */ #define NIL N /* index for root of binary search trees */ unsigned long printcount; void InitTreeOld(void) /* initialize trees */ { int i; /* For i = 0 to N - 1, rson[i] and lson[i] will be the right and left children of node i. These nodes need not be initialized. Also, dad[i] is the parent of node i. These are initialized to NIL (= N), which stands for 'not used.' For i = 0 to 255, rson[N + i + 1] is the root of the tree for strings that begin with character i. These are initialized to NIL. Note there are 256 trees. */ #ifndef _hufst_ for (i = N + 1; i <= N + 256; i++) rson[i] = NIL; for (i = 0; i < N; i++) dad[i] = NIL; #else for (i = N + 1; i <= N + 256; i++) rson[i] = 2*NIL; for (i = 0; i < N; i++) dad[i] = 2*NIL; #endif } void DecodeOld(void) /* Just the reverse of Encode(). */ { register int i, j, k, r, c; register unsigned int flags; long int todo=codesize,done=N; for (i = 0; i < N - F; i++) text_buf[i] = ' '; r = N - F; flags = 0; for ( ; ; ) { if (((flags >>= 1) & 256) == 0) { c = getc(infile); if (todo-- == 0) break; flags = c | 0xff00; /* uses higher byte cleverly */ } /* to count eight */ if (flags & 1) { if (todo-- == 0) break; c = getc(infile); if (outfile !=NULL) putc(c, outfile); text_buf[r++] = c; setcrc(c); if (done-- == 0) { if (!flg_n) putchar('*'); done=N;} r &= (N - 1); } else { if (todo-- == 0) break; i = getc(infile); if (todo-- == 0) break; j = getc(infile); i |= ((j & 0xf0) << 4); j = (j & 0x0f) + THRESHOLD; for (k = 0; k <= j; k++) { c = text_buf[(i + k) & (N - 1)]; if (outfile !=NULL) putc(c, outfile); setcrc(c); text_buf[r++] = c; r &= (N - 1); if (done-- == 0) { if (!flg_n) putchar('*'); done=N;} } } } }