4.4BSD/usr/src/contrib/news/trn3/uudecode.c
/* $Id: uudecode.c,v 4.4.3.1 1992/02/01 03:09:32 $
*
* Decode one or more uuencoded articles back to binary form.
* Trn version created by Wayne Davison.
* Formerly the nn version by Kim Storm.
* From the Berkeley original, modified by MSD, RDR, JPHD & WLS.
*/
/*
* This software is Copyright 1991 by Stan Barber.
*
* Permission is hereby granted to copy, reproduce, redistribute or otherwise
* use this software as long as: there is no monetary profit gained
* specifically from the use or reproduction of this software, it is not
* sold, rented, traded or otherwise marketed, and this copyright notice is
* included prominently in any copy made.
*
* The author make no claims as to the fitness or correctness of this software
* for any use whatsoever, and it is provided as is. Any use of this software
* is at the user's own risk.
*/
#include "EXTERN.h"
#include "common.h"
#include "respond.h"
#include "decode.h"
#define MAXCHAR 256
#define NORMLEN 64 /* allows for 84 encoded chars per line */
#define SEQMAX 'z'
#define SEQMIN 'a'
static char seqc;
static int first, secnd, check, numl;
static char blank;
static int chtbl[MAXCHAR], cdlen[NORMLEN + 3];
static int state;
static bool Xflag;
static int expecting_part;
static int decode_line _((char *));
static void inittbls _((void));
static void gettable _((FILE *));
#define NO_ADVANCE 0x10
#define FIND_BEGIN 0x01
#define AFTER_ERROR_FIND_BEGIN 0x02
#define DECODE_TEXT 0x03
#define SKIP_TRAILING (0x04 | NO_ADVANCE)
#define SKIP_LEADING 0x05
#define FOUND_END (0x06 | NO_ADVANCE)
#define DECODE_ERROR (0x07 | NO_ADVANCE)
#define OTHER_ERROR (0x08 | NO_ADVANCE)
#define NEW_BEGIN (0x09 | NO_ADVANCE)
void
uud_start()
{
Xflag = FALSE;
expecting_part = 0;
seqc = SEQMAX;
check = 1;
first = 1;
secnd = 0;
state = FIND_BEGIN;
}
int
uudecode(in)
FILE *in;
{
int mode, onedone, lens;
char buff[LBUFLEN];
numl = onedone = 0;
if (state == FIND_BEGIN)
inittbls();
/*
* search for header or translation table line.
*/
while ((state & NO_ADVANCE) || fgets(buff, sizeof buff, in) != Nullch) {
numl++;
switch (state) {
case NEW_BEGIN:
if (decode_fp != Nullfp) {
if (expecting_part) {
register int got_part = 0;
if (strnEQ(buff + 6, "part ", 5)) {
register char *bp;
for (bp = buff + 11; islower(*bp); bp++)
got_part = got_part * 26 + *bp - 'a';
}
if (expecting_part == got_part) {
state = DECODE_TEXT;
break;
}
printf("Expecting part %d; got part %d.\n",
expecting_part + 1, got_part + 1);
if (got_part) {
state = SKIP_LEADING;
return -1;
}
}
decode_end();
sleep(2);
Xflag = FALSE;
expecting_part = 0;
}
state = FIND_BEGIN;
/* fall thru */
case FIND_BEGIN:
case AFTER_ERROR_FIND_BEGIN:
if (strnEQ(buff, "table", 5)) {
gettable(in);
continue;
}
if (strnEQ(buff, "begin ", 6)
|| strnEQ(buff, "Xbegin ", 7)) {
lens = strlen(buff)-1;
if (buff[lens] == '\n')
buff[lens] = '\0';
if(sscanf(buff+6,"%o%s", &mode, decode_fname) != 2) {
register char *bp = buff + 6;
if (*bp == ' ')
bp++;
if (strnEQ(bp, "part ", 5)) {
register int got_part = 0;
for (bp = bp + 5; islower(*bp); bp++)
got_part = got_part * 26 + *bp - 'a';
printf("Expecting part 1; got part %d.\n",
got_part + 1);
return -1;
}
continue;
}
Xflag = (*buff == 'X');
sprintf(decode_dest, "%s/%s", extractdest, decode_fname);
if ((decode_fp = fopen(decode_dest, FOPEN_WB)) == Nullfp) {
printf("Cannot create file: %s\n", decode_dest);
goto err;
}
chmod(decode_dest, mode);
printf("Decoding: %s\n", decode_fname);
state = DECODE_TEXT;
}
continue;
case SKIP_LEADING:
state = decode_line(buff);
continue;
case DECODE_TEXT:
state = decode_line(buff);
onedone = 1;
continue;
case FOUND_END:
fclose(decode_fp);
decode_fp = Nullfp;
Xflag = FALSE;
expecting_part = 0;
state = FIND_BEGIN;
printf("Done.\n");
continue;
case SKIP_TRAILING:
printf("(Continued)\n");
state = SKIP_LEADING;
return 0;
case DECODE_ERROR:
state = SKIP_TRAILING;
continue;
case OTHER_ERROR:
fclose(decode_fp);
decode_fp = Nullfp;
Xflag = FALSE;
expecting_part = 0;
state = AFTER_ERROR_FIND_BEGIN;
goto err;
}
}
if (onedone) {
if (state == DECODE_TEXT) {
printf("(Continued)\n");
state = SKIP_LEADING;
}
return 0;
}
if (state == AFTER_ERROR_FIND_BEGIN)
return -1;
printf("Couldn't find anything to decode.\n");
err:
sleep(2);
return -1;
}
/*
* decode one line and write it out using decode_fp
*/
static int
decode_line(buff)
char *buff;
{
char outl[LBUFLEN];
register char *bp, *ut;
register int *trtbl = chtbl;
register int n;
register int blen; /* binary length (from decoded file) */
register int rlen; /* calculated input line length */
register int len; /* actual input line length */
register int dash; /* number of '-'s encountered on a line */
/* If it's too high, we reject the line */
# define REJECT(buf,rlen,len) \
((*buf == 'M' && len > rlen + 5) \
|| (*buf != 'M' && len != rlen && len != rlen+1) \
|| (strnEQ(buf, "BEGIN", 5)) \
|| (strnEQ(buf, "END", 3)))
if (Xflag) {
if (*buff == 'X')
buff++;
else
*buff = 'x'; /* force a mis-parse of a non-x'ed line */
}
len = strlen(buff);
if (--len <= 0)
return state;
buff[len] = '\0';
/*
* Get the binary line length.
*/
if ((blen = trtbl[buff[0]]) < 0) {
if (state == SKIP_LEADING) {
if (strnEQ(buff, "begin ", 6))
return NEW_BEGIN;
return SKIP_LEADING;
}
/*
* end of uuencoded file ?
*/
if (strnEQ(buff, "end", 3))
return FOUND_END;
/*
* end of current file ? : get next one.
*/
if (strnEQ(buff, "include ", 8)) {
for (bp = buff + 8; *bp; bp++) {
if (bp[0] == '.' && bp[1] == 'u') {
expecting_part = (bp[2] - 'a') * 26 + bp[3] - 'a';
break;
}
}
}
/*
* trailing garbage
*/
return SKIP_TRAILING;
}
rlen = cdlen[blen];
if (state == SKIP_LEADING && REJECT(buff,rlen,len))
return SKIP_LEADING;
/*
* Is it the empty line before the end line ?
*/
if (blen == 0)
return state;
if (REJECT(buff,rlen,len))
return SKIP_TRAILING;
/*
* Pad with blanks.
*/
for (bp = buff + len, n = rlen - len; --n >= 0; )
*bp++ = blank;
/*
* Verify
*/
for (n = rlen, bp = buff, dash = 0; --n >= 0; bp++) {
if (trtbl[*bp] < 0) {
if (state == SKIP_LEADING)
return SKIP_LEADING;
return DECODE_ERROR;
}
if (*bp == '-')
dash++;
}
if (dash * 100 / rlen > 33) /* more than 1/3 dashes? */
if (state == SKIP_LEADING)
return SKIP_LEADING; /* -> reject */
else
return SKIP_TRAILING;
/*
* Check for uuencodes that append a 'z' to each line....
*/
if (check)
if (secnd) {
secnd = 0;
if (buff[rlen] == SEQMAX)
check = 0;
} else if (first) {
first = 0;
secnd = 1;
if (buff[rlen] != SEQMAX)
check = 0;
}
/*
* There we check.
*/
if (check) {
if (buff[rlen] != seqc) {
if (state == SKIP_LEADING)
return SKIP_LEADING;
return DECODE_ERROR;
}
if (--seqc < SEQMIN)
seqc = SEQMAX;
}
/*
* output a group of 3 bytes (4 input characters).
* the input chars are pointed to by p, they are to
* be output to file f. blen is used to tell us not to
* output all of them at the end of the file.
*/
ut = outl;
n = blen;
bp = &buff[1];
while (--n >= 0) {
*(ut++) = trtbl[*bp] << 2 | trtbl[bp[1]] >> 4;
if (n > 0) {
*(ut++) = (trtbl[bp[1]] << 4) | (trtbl[bp[2]] >> 2);
n--;
}
if (n > 0) {
*(ut++) = trtbl[bp[2]] << 6 | trtbl[bp[3]];
n--;
}
bp += 4;
}
if (fwrite(outl, 1, blen, decode_fp) <= 0) {
printf("Error on writing decoded file\n");
return OTHER_ERROR;
}
return DECODE_TEXT;
}
/*
* Install the table in memory for later use.
*/
static void
inittbls()
{
register int i, j;
/*
* Set up the default translation table.
*/
for (i = 0; i < ' '; i++)
chtbl[i] = -1;
for (i = ' ', j = 0; i < ' ' + 64; i++, j++)
chtbl[i] = j;
for (i = ' ' + 64; i < MAXCHAR; i++)
chtbl[i] = -1;
chtbl['`'] = chtbl[' ']; /* common mutation */
chtbl['~'] = chtbl['^']; /* another common mutation */
blank = ' ';
/*
* set up the line length table, to avoid computing lotsa * and / ...
*/
cdlen[0] = 1;
for (i = 1, j = 5; i <= NORMLEN; i += 3, j += 4)
cdlen[i] = (cdlen[i + 1] = (cdlen[i + 2] = j));
}
static void
gettable(in)
FILE *in;
{
char buff[LBUFLEN];
register int c, n = 0;
register char *cpt;
for (c = 0; c < MAXCHAR; c++)
chtbl[c] = -1;
for (;;) {
if (fgets(buff, sizeof buff, in) == Nullch) {
printf("EOF while in translation table.\n");
return;
}
numl++;
if (strnEQ(buff, "begin", 5)) {
printf("Incomplete translation table.\n");
return;
}
cpt = buff + strlen(buff) - 1;
*cpt = ' ';
while (*cpt == ' ') {
*cpt = 0;
cpt--;
}
cpt = buff;
while (c = *cpt) {
if (chtbl[c] != -1) {
printf("Duplicate char in translation table.\n");
return;
}
if (n == 0)
blank = c;
chtbl[c] = n++;
if (n >= 64)
return;
cpt++;
}
}
}