mirror of
https://github.com/xcat2/xNBA.git
synced 2024-11-27 03:39:15 +00:00
765 lines
19 KiB
C
765 lines
19 KiB
C
/*
|
|
----------------------------------------------------------------------------
|
|
|
|
M. LZHuf Compression
|
|
|
|
This is the LZHuf compression algorithm as used in DPBOX and F6FBB.
|
|
|
|
----------------------------------------------------------------------------
|
|
*/
|
|
/**************************************************************
|
|
lzhuf.c
|
|
written by Haruyasu Yoshizaki 11/20/1988
|
|
some minor changes 4/6/1989
|
|
comments translated by Haruhiko Okumura 4/7/1989
|
|
|
|
minor beautifications and adjustments for compiling under Linux
|
|
by Markus Gutschke <gutschk@math.uni-muenster.de>
|
|
1997-01-27
|
|
|
|
Modifications to allow use as a filter by Ken Yap <ken_yap@users.sourceforge.net>.
|
|
1997-07-01
|
|
|
|
Small mod to cope with running on big-endian machines
|
|
by Jim Hague <jim.hague@acm.org)
|
|
1998-02-06
|
|
|
|
Make compression statistics report shorter
|
|
by Ken Yap <ken_yap@users.sourceforge.net>.
|
|
2001-04-25
|
|
**************************************************************/
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <ctype.h>
|
|
#include <errno.h>
|
|
|
|
#ifndef VERBOSE
|
|
#define Fprintf(x)
|
|
#define wterr 0
|
|
#else
|
|
#define Fprintf(x) fprintf x
|
|
#if defined(ENCODE) || defined(DECODE)
|
|
static char wterr[] = "Can't write.";
|
|
#ifdef ENCODE
|
|
static unsigned long int codesize = 0;
|
|
#endif
|
|
static unsigned long int printcount = 0;
|
|
#endif
|
|
#endif
|
|
|
|
#ifndef MAIN
|
|
extern
|
|
#endif
|
|
FILE *infile, *outfile;
|
|
|
|
#if defined(ENCODE) || defined(DECODE)
|
|
static unsigned long int textsize = 0;
|
|
|
|
static __inline__ void Error(char *message)
|
|
{
|
|
Fprintf((stderr, "\n%s\n", message));
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
|
|
/* These will be a complete waste of time on a lo-endian */
|
|
/* system, but it only gets done once so WTF. */
|
|
static unsigned long i86ul_to_host(unsigned long ul)
|
|
{
|
|
unsigned long res = 0;
|
|
int i;
|
|
union
|
|
{
|
|
unsigned char c[4];
|
|
unsigned long ul;
|
|
} u;
|
|
|
|
u.ul = ul;
|
|
for (i = 3; i >= 0; i--)
|
|
res = (res << 8) + u.c[i];
|
|
return res;
|
|
}
|
|
|
|
static unsigned long host_to_i86ul(unsigned long ul)
|
|
{
|
|
int i;
|
|
union
|
|
{
|
|
unsigned char c[4];
|
|
unsigned long ul;
|
|
} u;
|
|
|
|
for (i = 0; i < 4; i++)
|
|
{
|
|
u.c[i] = ul & 0xff;
|
|
ul >>= 8;
|
|
}
|
|
return u.ul;
|
|
}
|
|
#endif
|
|
|
|
/********** LZSS compression **********/
|
|
|
|
#define N 4096 /* buffer size */
|
|
/* Attention: When using this file for f6fbb-type compressed data exchange,
|
|
set N to 2048 ! (DL8HBS) */
|
|
#define F 60 /* lookahead buffer size */
|
|
#define THRESHOLD 2
|
|
#define NIL N /* leaf of tree */
|
|
|
|
#if defined(ENCODE) || defined(DECODE)
|
|
static unsigned char
|
|
text_buf[N + F - 1];
|
|
#endif
|
|
|
|
#ifdef ENCODE
|
|
static int match_position, match_length,
|
|
lson[N + 1], rson[N + 257], dad[N + 1];
|
|
|
|
static void InitTree(void) /* initialize trees */
|
|
{
|
|
int i;
|
|
|
|
for (i = N + 1; i <= N + 256; i++)
|
|
rson[i] = NIL; /* root */
|
|
for (i = 0; i < N; i++)
|
|
dad[i] = NIL; /* node */
|
|
}
|
|
|
|
static void InsertNode(int r) /* insert to tree */
|
|
{
|
|
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 */
|
|
}
|
|
|
|
static void DeleteNode(int p) /* remove from tree */
|
|
{
|
|
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;
|
|
}
|
|
#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 */
|
|
|
|
#ifdef ENCODE
|
|
static 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
|
|
};
|
|
|
|
static 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
|
|
};
|
|
#endif
|
|
|
|
#ifdef DECODE
|
|
/* for decoding */
|
|
static 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,
|
|
};
|
|
|
|
static 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,
|
|
};
|
|
#endif
|
|
|
|
#if defined(ENCODE) || defined(DECODE)
|
|
static unsigned freq[T + 1]; /* frequency table */
|
|
|
|
static 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. */
|
|
|
|
static int son[T]; /* pointers to child nodes (son[], son[] + 1) */
|
|
#endif
|
|
|
|
#ifdef DECODE
|
|
static unsigned getbuf = 0;
|
|
static uchar getlen = 0;
|
|
|
|
static int GetBit(void) /* get one bit */
|
|
{
|
|
int i;
|
|
|
|
while (getlen <= 8) {
|
|
if ((i = getc(infile)) < 0) i = 0;
|
|
getbuf |= i << (8 - getlen);
|
|
getlen += 8;
|
|
}
|
|
i = getbuf;
|
|
getbuf <<= 1;
|
|
getlen--;
|
|
return ((signed short)i < 0);
|
|
}
|
|
|
|
static int GetByte(void) /* get one byte */
|
|
{
|
|
unsigned short i;
|
|
|
|
while (getlen <= 8) {
|
|
if ((signed short)(i = getc(infile)) < 0) i = 0;
|
|
getbuf |= i << (8 - getlen);
|
|
getlen += 8;
|
|
}
|
|
i = getbuf;
|
|
getbuf <<= 8;
|
|
getlen -= 8;
|
|
return i >> 8;
|
|
}
|
|
#endif
|
|
|
|
#ifdef ENCODE
|
|
static unsigned putbuf = 0;
|
|
static uchar putlen = 0;
|
|
|
|
static void Putcode(int l, unsigned c) /* output c bits of code */
|
|
{
|
|
putbuf |= c >> putlen;
|
|
if ((putlen += l) >= 8) {
|
|
if (putc(putbuf >> 8, outfile) == EOF) {
|
|
Error(wterr);
|
|
}
|
|
if ((putlen -= 8) >= 8) {
|
|
if (putc(putbuf, outfile) == EOF) {
|
|
Error(wterr);
|
|
}
|
|
#ifdef VERBOSE
|
|
codesize += 2;
|
|
#endif
|
|
putlen -= 8;
|
|
putbuf = c << (l - putlen);
|
|
} else {
|
|
putbuf <<= 8;
|
|
#ifdef VERBOSE
|
|
codesize++;
|
|
#endif
|
|
}
|
|
}
|
|
}
|
|
#endif
|
|
|
|
/* initialization of tree */
|
|
|
|
#if defined(ENCODE) || defined(DECODE)
|
|
static void StartHuff(void)
|
|
{
|
|
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;
|
|
}
|
|
|
|
/* reconstruction of tree */
|
|
|
|
static void reconst(void)
|
|
{
|
|
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 */
|
|
|
|
static void update(int c)
|
|
{
|
|
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 */
|
|
}
|
|
#endif
|
|
|
|
#ifdef ENCODE
|
|
#if 0
|
|
static unsigned code, len;
|
|
#endif
|
|
|
|
static void EncodeChar(unsigned c)
|
|
{
|
|
unsigned i;
|
|
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);
|
|
#if 0
|
|
code = i;
|
|
len = j;
|
|
#endif
|
|
update(c);
|
|
}
|
|
|
|
static void EncodePosition(unsigned c)
|
|
{
|
|
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);
|
|
}
|
|
|
|
static void EncodeEnd(void)
|
|
{
|
|
if (putlen) {
|
|
if (putc(putbuf >> 8, outfile) == EOF) {
|
|
Error(wterr);
|
|
}
|
|
#ifdef VERBOSE
|
|
codesize++;
|
|
#endif
|
|
}
|
|
}
|
|
#endif
|
|
|
|
#ifdef DECODE
|
|
static int DecodeChar(void)
|
|
{
|
|
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;
|
|
}
|
|
|
|
static int DecodePosition(void)
|
|
{
|
|
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);
|
|
}
|
|
#endif
|
|
|
|
#ifdef ENCODE
|
|
/* compression */
|
|
|
|
void Encode(void) /* compression */
|
|
{
|
|
int i, c, len, r, s, last_match_length;
|
|
unsigned long tw;
|
|
|
|
fseek(infile, 0L, 2);
|
|
textsize = ftell(infile);
|
|
#ifdef VERBOSE
|
|
if ((signed long)textsize < 0)
|
|
Fprintf((stderr, "Errno: %d", errno));
|
|
#endif
|
|
tw = host_to_i86ul(textsize);
|
|
if (fwrite(&tw, sizeof tw, 1, outfile) < 1)
|
|
Error(wterr); /* output size of text */
|
|
if (textsize == 0)
|
|
return;
|
|
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 = 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 = 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) {
|
|
#if defined(VERBOSE) && defined(EXTRAVERBOSE)
|
|
Fprintf((stderr, "%12ld\r", textsize));
|
|
#endif
|
|
printcount += 1024;
|
|
}
|
|
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();
|
|
#ifdef LONG_REPORT
|
|
Fprintf((stderr, "input size %ld bytes\n", codesize));
|
|
Fprintf((stderr, "output size %ld bytes\n", textsize));
|
|
Fprintf((stderr, "input/output %.3f\n", (double)codesize / textsize));
|
|
#else
|
|
Fprintf((stderr, "input/output = %ld/%ld = %.3f\n", codesize, textsize,
|
|
(double)codesize / textsize));
|
|
#endif
|
|
}
|
|
#endif
|
|
|
|
#ifdef DECODE
|
|
void Decode(void) /* recover */
|
|
{
|
|
int i, j, k, r, c;
|
|
unsigned long int count;
|
|
unsigned long tw;
|
|
|
|
if (fread(&tw, sizeof tw, 1, infile) < 1)
|
|
Error("Can't read"); /* read size of text */
|
|
textsize = i86ul_to_host(tw);
|
|
if (textsize == 0)
|
|
return;
|
|
StartHuff();
|
|
for (i = 0; i < N - F; i++)
|
|
text_buf[i] = ' ';
|
|
r = N - F;
|
|
for (count = 0; count < textsize; ) {
|
|
c = DecodeChar();
|
|
if (c < 256) {
|
|
if (putc(c, outfile) == EOF) {
|
|
Error(wterr);
|
|
}
|
|
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)];
|
|
if (putc(c, outfile) == EOF) {
|
|
Error(wterr);
|
|
}
|
|
text_buf[r++] = c;
|
|
r &= (N - 1);
|
|
count++;
|
|
}
|
|
}
|
|
if (count > printcount) {
|
|
#if defined(VERBOSE) && defined(EXTRAVERBOSE)
|
|
Fprintf((stderr, "%12ld\r", count));
|
|
#endif
|
|
printcount += 1024;
|
|
}
|
|
}
|
|
Fprintf((stderr, "%12ld\n", count));
|
|
}
|
|
#endif
|
|
|
|
#ifdef MAIN
|
|
int main(int argc, char *argv[])
|
|
{
|
|
char *s;
|
|
FILE *f;
|
|
int c;
|
|
|
|
if (argc == 2) {
|
|
outfile = stdout;
|
|
if ((f = tmpfile()) == NULL) {
|
|
perror("tmpfile");
|
|
return EXIT_FAILURE;
|
|
}
|
|
while ((c = getchar()) != EOF)
|
|
fputc(c, f);
|
|
rewind(infile = f);
|
|
}
|
|
else if (argc != 4) {
|
|
Fprintf((stderr, "'lzhuf e file1 file2' encodes file1 into file2.\n"
|
|
"'lzhuf d file2 file1' decodes file2 into file1.\n"));
|
|
return EXIT_FAILURE;
|
|
}
|
|
if (argc == 4) {
|
|
if ((s = argv[1], s[1] || strpbrk(s, "DEde") == NULL)
|
|
|| (s = argv[2], (infile = fopen(s, "rb")) == NULL)
|
|
|| (s = argv[3], (outfile = fopen(s, "wb")) == NULL)) {
|
|
Fprintf((stderr, "??? %s\n", s));
|
|
return EXIT_FAILURE;
|
|
}
|
|
}
|
|
if (toupper(*argv[1]) == 'E')
|
|
Encode();
|
|
else
|
|
Decode();
|
|
fclose(infile);
|
|
fclose(outfile);
|
|
return EXIT_SUCCESS;
|
|
}
|
|
#endif
|