Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!cs.utexas.edu!tut.cis.ohio-state.edu!ucbvax!WSMR-SIMTEL20.ARMY.MIL!w8sdz
From: w8sdz@WSMR-SIMTEL20.ARMY.MIL (Keith Petersen)
Newsgroups: comp.binaries.ibm.pc.d
Subject: Freely-distributable uudecode for Unix
Message-ID: <KPETERSEN.12550482989.BABYL@WSMR-SIMTEL20.ARMY.MIL>
Date: 16 Dec 89 07:02:00 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Lines: 182

Some readers of this list have reported problems uudecoding files sent
by LISTSERV (or TRICKLE in Europe) which contain a "M" at the end of
each line and on the final line just before the "end" statement.

The first character in each line defines the number of bytes of data
which follow on that line.  If the uudecoder is working correctly the
trailing "M" should be ignored.  It is added by LISTSERV to get around
problems of some mailers dropping trailing blanks.

Here is a freely distributable uudecode for Unix that does the "right
thing", courtesy of UC Berkeley.

Keith
--
Keith Petersen
Maintainer of SIMTEL20's CP/M, MSDOS, & MISC archives [IP address 26.2.0.74]
Internet: w8sdz@WSMR-SIMTEL20.Army.Mil, w8sdz@brl.arpa  BITNET: w8sdz@NDSUVM1
Uucp: {ames,decwrl,harvard,rutgers,ucbvax,uunet}!wsmr-simtel20.army.mil!w8sdz

---cut-here---
/*
 * Copyright (c) 1983 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that the above copyright notice and this paragraph are
 * duplicated in all such forms and that any documentation,
 * advertising materials, and other materials related to such
 * distribution and use acknowledge that the software was developed
 * by the University of California, Berkeley.  The name of the
 * University may not be used to endorse or promote products derived
 * from this software without specific prior written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

#ifndef lint
static char sccsid[] = "@(#)uudecode.c	5.5 (Berkeley) 7/6/88";
#endif /* not lint */

/*
 * uudecode [input]
 *
 * create the specified file, decoding as you go.
 * used with uuencode.
 */
#include <stdio.h>
#include <pwd.h>
#include <sys/types.h>
#include <sys/stat.h>

/* single character decode */
#define DEC(c)	(((c) - ' ') & 077)

main(argc, argv)
char **argv;
{
	FILE *in, *out;
	int mode;
	char dest[128];
	char buf[80];

	/* optional input arg */
	if (argc > 1) {
		if ((in = fopen(argv[1], "r")) == NULL) {
			perror(argv[1]);
			exit(1);
		}
		argv++; argc--;
	} else
		in = stdin;

	if (argc != 1) {
		printf("Usage: uudecode [infile]\n");
		exit(2);
	}

	/* search for header line */
	for (;;) {
		if (fgets(buf, sizeof buf, in) == NULL) {
			fprintf(stderr, "No begin line\n");
			exit(3);
		}
		if (strncmp(buf, "begin ", 6) == 0)
			break;
	}
	(void)sscanf(buf, "begin %o %s", &mode, dest);

	/* handle ~user/file format */
	if (dest[0] == '~') {
		char *sl;
		struct passwd *getpwnam();
		struct passwd *user;
		char dnbuf[100], *index(), *strcat(), *strcpy();

		sl = index(dest, '/');
		if (sl == NULL) {
			fprintf(stderr, "Illegal ~user\n");
			exit(3);
		}
		*sl++ = 0;
		user = getpwnam(dest+1);
		if (user == NULL) {
			fprintf(stderr, "No such user as %s\n", dest);
			exit(4);
		}
		strcpy(dnbuf, user->pw_dir);
		strcat(dnbuf, "/");
		strcat(dnbuf, sl);
		strcpy(dest, dnbuf);
	}

	/* create output file */
	out = fopen(dest, "w");
	if (out == NULL) {
		perror(dest);
		exit(4);
	}
	chmod(dest, mode);

	decode(in, out);

	if (fgets(buf, sizeof buf, in) == NULL || strcmp(buf, "end\n")) {
		fprintf(stderr, "No end line\n");
		exit(5);
	}
	exit(0);
}

/*
 * copy from in to out, decoding as you go along.
 */
decode(in, out)
FILE *in;
FILE *out;
{
	char buf[80];
	char *bp;
	int n;

	for (;;) {
		/* for each input line */
		if (fgets(buf, sizeof buf, in) == NULL) {
			printf("Short file\n");
			exit(10);
		}
		n = DEC(buf[0]);
		if (n <= 0)
			break;

		bp = &buf[1];
		while (n > 0) {
			outdec(bp, out, n);
			bp += 4;
			n -= 3;
		}
	}
}

/*
 * 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.  n is used to tell us not to
 * output all of them at the end of the file.
 */
outdec(p, f, n)
char *p;
FILE *f;
{
	int c1, c2, c3;

	c1 = DEC(*p) << 2 | DEC(p[1]) >> 4;
	c2 = DEC(p[1]) << 4 | DEC(p[2]) >> 2;
	c3 = DEC(p[2]) << 6 | DEC(p[3]);
	if (n >= 1)
		putc(c1, f);
	if (n >= 2)
		putc(c2, f);
	if (n >= 3)
		putc(c3, f);
}