/*$Source: /usr/home/dhesi/booz/RCS/decode.c,v $*/
/*$Id: decode.c,v 1.8 91/07/08 12:06:52 dhesi Exp $*/
/***********************************************************
Adapted from "ar" archiver written by Haruhiko Okumura.
***********************************************************/
#include "booz.h"
#include "zoo.h"
#include "ar.h"
#include "lzh.h"
extern int decoded; /* from huf.c */
static int j; /* remaining bytes to copy */
/* must call this before decoding each file */
int decode_start()
{
huf_decode_start();
j = 0;
decoded = 0;
}
/* decodes up to 'count' chars (but no more than DICSIZ) into supplied
buffer; returns actual count. */
int decode(count, buffer)
uint count;
uchar buffer[];
{
static uint i;
uint r, c;
r = 0;
while (--j >= 0) {
buffer[r] = buffer[i];
i = (i + 1) & (DICSIZ - 1);
if (++r == count)
return r;
}
for ( ; ; ) {
c = decode_c();
if (decoded)
return r;
if (c buffer[r] = c;
if (++r == count)
return r;
} else {
j = c - (UCHAR_MAX + 1 - THRESHOLD);
i = (r - decode_p() - 1) & (DICSIZ - 1);
while (--j >= 0) {
buffer[r] = buffer[i];
i = (i + 1) & (DICSIZ - 1);
if (++r == count)
return r;
}
}
}
}
FILE *arcfile;
extern char out_buf_adr[]; /* address of buffer */
/*
lzh_decode decodes its input and sends it to output.
Should return error status or byte count, but currently
returns 0.
*/
int lzh_decode(infile, outfile)
FILE *infile;
FILE *outfile;
{
int n;
extern int decoded;
arcfile = infile; /* stream to be decoded */
decode_start();
while (!decoded) {
n = decode((uint) DICSIZ, (uchar *)out_buf_adr);
/* n = count of chars decoded */
fwrite_crc(out_buf_adr, n, outfile);
}
return 0;
}
