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#include "macunpack.h"
#ifdef SIT
#define DELZAH
#endif /* SIT */
#ifdef LZH
#define DELZAH
#endif /* LZH */
#ifdef DELZAH
#include "globals.h"
#include "../util/masks.h"
#include "../fileio/wrfile.h"
/* Note: compare with LZSS decoding in lharc! */
#define N 314
#define T (2*N-1)
/* Huffman table used for first 6 bits of offset:
#bits codes
3 0x000
4 0x040-0x080
5 0x100-0x2c0
6 0x300-0x5c0
7 0x600-0xbc0
8 0xc00-0xfc0
*/
static unsigned short HuffCode[] = {
0x000, 0x000, 0x000, 0x000, 0x000, 0x000, 0x000, 0x000,
0x000, 0x000, 0x000, 0x000, 0x000, 0x000, 0x000, 0x000,
0x000, 0x000, 0x000, 0x000, 0x000, 0x000, 0x000, 0x000,
0x000, 0x000, 0x000, 0x000, 0x000, 0x000, 0x000, 0x000,
0x040, 0x040, 0x040, 0x040, 0x040, 0x040, 0x040, 0x040,
0x040, 0x040, 0x040, 0x040, 0x040, 0x040, 0x040, 0x040,
0x080, 0x080, 0x080, 0x080, 0x080, 0x080, 0x080, 0x080,
0x080, 0x080, 0x080, 0x080, 0x080, 0x080, 0x080, 0x080,
0x0c0, 0x0c0, 0x0c0, 0x0c0, 0x0c0, 0x0c0, 0x0c0, 0x0c0,
0x0c0, 0x0c0, 0x0c0, 0x0c0, 0x0c0, 0x0c0, 0x0c0, 0x0c0,
0x100, 0x100, 0x100, 0x100, 0x100, 0x100, 0x100, 0x100,
0x140, 0x140, 0x140, 0x140, 0x140, 0x140, 0x140, 0x140,
0x180, 0x180, 0x180, 0x180, 0x180, 0x180, 0x180, 0x180,
0x1c0, 0x1c0, 0x1c0, 0x1c0, 0x1c0, 0x1c0, 0x1c0, 0x1c0,
0x200, 0x200, 0x200, 0x200, 0x200, 0x200, 0x200, 0x200,
0x240, 0x240, 0x240, 0x240, 0x240, 0x240, 0x240, 0x240,
0x280, 0x280, 0x280, 0x280, 0x280, 0x280, 0x280, 0x280,
0x2c0, 0x2c0, 0x2c0, 0x2c0, 0x2c0, 0x2c0, 0x2c0, 0x2c0,
0x300, 0x300, 0x300, 0x300, 0x340, 0x340, 0x340, 0x340,
0x380, 0x380, 0x380, 0x380, 0x3c0, 0x3c0, 0x3c0, 0x3c0,
0x400, 0x400, 0x400, 0x400, 0x440, 0x440, 0x440, 0x440,
0x480, 0x480, 0x480, 0x480, 0x4c0, 0x4c0, 0x4c0, 0x4c0,
0x500, 0x500, 0x500, 0x500, 0x540, 0x540, 0x540, 0x540,
0x580, 0x580, 0x580, 0x580, 0x5c0, 0x5c0, 0x5c0, 0x5c0,
0x600, 0x600, 0x640, 0x640, 0x680, 0x680, 0x6c0, 0x6c0,
0x700, 0x700, 0x740, 0x740, 0x780, 0x780, 0x7c0, 0x7c0,
0x800, 0x800, 0x840, 0x840, 0x880, 0x880, 0x8c0, 0x8c0,
0x900, 0x900, 0x940, 0x940, 0x980, 0x980, 0x9c0, 0x9c0,
0xa00, 0xa00, 0xa40, 0xa40, 0xa80, 0xa80, 0xac0, 0xac0,
0xb00, 0xb00, 0xb40, 0xb40, 0xb80, 0xb80, 0xbc0, 0xbc0,
0xc00, 0xc40, 0xc80, 0xcc0, 0xd00, 0xd40, 0xd80, 0xdc0,
0xe00, 0xe40, 0xe80, 0xec0, 0xf00, 0xf40, 0xf80, 0xfc0};
static short HuffLength[] = {
3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8};
unsigned char (*lzah_getbyte)();
static void lzah_inithuf();
static void lzah_reorder();
static void lzah_move();
static void lzah_getbit();
static void lzah_outchar();
static char lzah_buf[4096];
static int lzah_bufptr;
static int lzah_bitsavail;
static int lzah_bits;
static int Frequ[1000];
static int ForwTree[1000];
static int BackTree[1000];
void de_lzah(obytes)
unsigned long obytes;
{
int i, i1, j, ch, byte, offs, skip;
lzah_inithuf();
lzah_bitsavail = 0;
for(i = 0; i < 4036; i++) {
lzah_buf[i] = ' ';
}
lzah_bufptr = 4036;
while(obytes != 0) {
ch = ForwTree[T - 1];
while(ch < T) {
lzah_getbit();
if(lzah_bits & 0x80) {
ch = ch + 1;
}
ch = ForwTree[ch];
}
ch -= T;
if(Frequ[T - 1] >= 0x8000) {
lzah_reorder();
}
i = BackTree[ch + T];
do {
j = ++Frequ[i];
i1 = i + 1;
if(Frequ[i1] < j) {
while(Frequ[++i1] < j) ;
i1--;
Frequ[i] = Frequ[i1];
Frequ[i1] = j;
j = ForwTree[i];
BackTree[j] = i1;
if(j < T) {
BackTree[j + 1] = i1;
}
ForwTree[i] = ForwTree[i1];
ForwTree[i1] = j;
j = ForwTree[i];
BackTree[j] = i;
if(j < T) {
BackTree[j + 1] = i;
}
i = i1;
}
i = BackTree[i];
} while(i != 0);
if(ch < 256) {
lzah_outchar((char)ch);
obytes--;
} else {
if(lzah_bitsavail != 0) {
byte = (lzah_bits << 1) & BYTEMASK;
lzah_bits = (*lzah_getbyte)() & BYTEMASK;
byte |= (lzah_bits >> lzah_bitsavail);
lzah_bits = lzah_bits << (7 - lzah_bitsavail);
} else {
byte = (*lzah_getbyte)() & BYTEMASK;
}
offs = HuffCode[byte];
skip = HuffLength[byte] - 2;
while(skip-- != 0) {
byte = byte + byte;
lzah_getbit();
if(lzah_bits & 0x80) {
byte++;
}
}
offs |= (byte & 0x3f);
offs = ((lzah_bufptr - offs - 1) & 0xfff);
ch = ch - 253;
while(ch-- > 0) {
lzah_outchar(lzah_buf[offs++ & 0xfff]);
obytes--;
if(obytes == 0) {
break;
}
}
}
}
}
static void lzah_inithuf()
{
int i, j;
for(i = 0; i < N; i++) {
Frequ[i] = 1;
ForwTree[i] = i + T;
BackTree[i + T] = i;
}
for(i = 0, j = N; j < T; i += 2, j++) {
Frequ[j] = Frequ[i] + Frequ[i + 1];
ForwTree[j] = i;
BackTree[i] = j;
BackTree[i + 1] = j;
}
Frequ[T] = 0xffff;
BackTree[T - 1] = 0;
}
static void lzah_reorder()
{
int i, j, k, l;
j = 0;
for(i = 0; i < T; i++) {
if(ForwTree[i] >= T) {
Frequ[j] = ((Frequ[i] + 1) >> 1);
ForwTree[j] = ForwTree[i];
j++;
}
}
for(i = 0, j = N; i < T; i += 2, j++) {
k = i + 1;
l = Frequ[i] + Frequ[k];
Frequ[j] = l;
k = j - 1;
while(l < Frequ[k]) {
k--;
}
k = k + 1;
lzah_move(Frequ + k, Frequ + k + 1, j - k);
Frequ[k] = l;
lzah_move(ForwTree + k, ForwTree + k + 1, j - k);
ForwTree[k] = i;
}
for(i = 0; i < T; i++) {
k = ForwTree[i];
if(k >= T) {
BackTree[k] = i;
} else {
BackTree[k] = i;
BackTree[k + 1] = i;
}
}
}
static void lzah_move(p, q, n)
int *p, *q, n;
{
if(p > q) {
while(n-- > 0) {
*q++ = *p++;
}
} else {
p += n;
q += n;
while(n-- > 0) {
*--q = *--p;
}
}
}
static void lzah_getbit()
{
if(lzah_bitsavail != 0) {
lzah_bits = lzah_bits + lzah_bits;
lzah_bitsavail--;
} else {
lzah_bits = (*lzah_getbyte)() & BYTEMASK;
lzah_bitsavail = 7;
}
}
static void lzah_outchar(ch)
char ch;
{
*out_ptr++ = ch;
lzah_buf[lzah_bufptr++] = ch;
lzah_bufptr &= 0xfff;
}
#else /* DELZAH */
int delzah; /* keep lint and some compilers happy */
#endif /* DELZAH */
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.