xref: /netbsd-src/usr.bin/uudecode/uudecode.c (revision aaf4ece63a859a04e37cf3a7229b5fab0157cc06)
1 /*	$NetBSD: uudecode.c,v 1.20 2005/06/29 20:35:32 wiz Exp $	*/
2 
3 /*-
4  * Copyright (c) 1983, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #if HAVE_NBTOOL_CONFIG_H
33 #include "nbtool_config.h"
34 #endif
35 
36 #include <sys/cdefs.h>
37 #if !defined(lint)
38 __COPYRIGHT("@(#) Copyright (c) 1983, 1993\n\
39 	The Regents of the University of California.  All rights reserved.\n");
40 #if 0
41 static char sccsid[] = "@(#)uudecode.c	8.2 (Berkeley) 4/2/94";
42 #endif
43 __RCSID("$NetBSD: uudecode.c,v 1.20 2005/06/29 20:35:32 wiz Exp $");
44 #endif /* not lint */
45 
46 /*
47  * uudecode [file ...]
48  *
49  * create the specified file, decoding as you go.
50  * used with uuencode.
51  */
52 #include <sys/param.h>
53 #include <sys/stat.h>
54 #include <ctype.h>
55 #include <err.h>
56 #include <errno.h>
57 #include <limits.h>
58 #include <locale.h>
59 #include <pwd.h>
60 #include <stdio.h>
61 #include <stdlib.h>
62 #include <string.h>
63 #include <unistd.h>
64 
65 static int decode(void);
66 static void usage(void);
67 int main(int, char *[]);
68 
69 int pflag;
70 char *filename;
71 
72 int
73 main(int argc, char *argv[])
74 {
75 	int ch, rval;
76 
77 	setlocale(LC_ALL, "");
78 	setprogname(argv[0]);
79 
80 	pflag = 0;
81 	while ((ch = getopt(argc, argv, "p")) != -1)
82 		switch (ch) {
83 		case 'p':
84 			pflag = 1;
85 			break;
86 		default:
87 			usage();
88 		}
89 	argc -= optind;
90 	argv += optind;
91 
92 	if (*argv) {
93 		rval = 0;
94 		do {
95 			if (!freopen(filename = *argv, "r", stdin)) {
96 				warn("%s", *argv);
97 				rval = 1;
98 				continue;
99 			}
100 			rval |= decode();
101 		} while (*++argv);
102 	} else {
103 		filename = "stdin";
104 		rval = decode();
105 	}
106 	exit(rval);
107 }
108 
109 static int
110 decode(void)
111 {
112 	struct passwd *pw;
113 	int n;
114 	char ch, *p;
115 	int n1;
116 	long mode;
117 	char *fn;
118 	char buf[MAXPATHLEN];
119 
120 	/* search for header line */
121 	do {
122 		if (!fgets(buf, sizeof(buf), stdin)) {
123 			warnx("%s: no \"begin\" line", filename);
124 			return(1);
125 		}
126 	} while (strncmp(buf, "begin ", 6));
127         /* must be followed by an octal mode and a space */
128 	mode = strtol(buf + 6, &fn, 8);
129 	if (fn == (buf+6) || !isspace((unsigned char)*fn) || mode==LONG_MIN || mode==LONG_MAX)
130 	{
131 	        warnx("%s: invalid mode on \"begin\" line", filename);
132 		return(1);
133 	}
134 	/* skip whitespace for file name */
135 	while (*fn && isspace((unsigned char)*fn)) fn++;
136 	if (*fn == 0) {
137                 warnx("%s: no filename on \"begin\" line", filename);
138 		return(1);
139 	}
140 	/* zap newline */
141 	for (p = fn; *p && *p != '\n'; p++)
142 	        ;
143 	if (*p) *p = 0;
144 
145 	/* handle ~user/file format */
146 	if (*fn == '~') {
147 		if (!(p = strchr(fn, '/'))) {
148 			warnx("%s: illegal ~user.", filename);
149 			return(1);
150 		}
151 		*p++ = '\0';
152 		if (!(pw = getpwnam(fn + 1))) {
153 			warnx("%s: no user %s.", filename, buf);
154 			return(1);
155 		}
156 		n = strlen(pw->pw_dir);
157 		n1 = strlen(p);
158 		if (n + n1 + 2 > MAXPATHLEN) {
159 			warnx("%s: path too long.", filename);
160 			return(1);
161 		}
162 		/* make space at beginning of buf by moving end of pathname */
163 		memmove(buf + n + 1, p, n1 + 1);
164 		memmove(buf, pw->pw_dir, n);
165 		buf[n] = '/';
166 		fn = buf;
167 	}
168 
169 	/* create output file, set mode */
170 	if (!pflag && (!freopen(fn, "w", stdout) ||
171 	    fchmod(fileno(stdout), mode & 0666))) {
172 		warn("%s: %s", fn, filename);
173 		return(1);
174 	}
175 
176 	/* for each input line */
177 	for (;;) {
178 		if (!fgets(p = buf, sizeof(buf), stdin)) {
179 			warnx("%s: short file.", filename);
180 			return(1);
181 		}
182 #define	DEC(c)	(((c) - ' ') & 077)		/* single character decode */
183 		/*
184 		 * `n' is used to avoid writing out all the characters
185 		 * at the end of the file.
186 		 */
187 		if ((n = DEC(*p)) <= 0)
188 			break;
189 		for (++p; n > 0; p += 4, n -= 3)
190 			if (n >= 3) {
191 				ch = DEC(p[0]) << 2 | DEC(p[1]) >> 4;
192 				putchar(ch);
193 				ch = DEC(p[1]) << 4 | DEC(p[2]) >> 2;
194 				putchar(ch);
195 				ch = DEC(p[2]) << 6 | DEC(p[3]);
196 				putchar(ch);
197 			}
198 			else {
199 				if (n >= 1) {
200 					ch = DEC(p[0]) << 2 | DEC(p[1]) >> 4;
201 					putchar(ch);
202 				}
203 				if (n >= 2) {
204 					ch = DEC(p[1]) << 4 | DEC(p[2]) >> 2;
205 					putchar(ch);
206 				}
207 				if (n >= 3) {
208 					ch = DEC(p[2]) << 6 | DEC(p[3]);
209 					putchar(ch);
210 				}
211 			}
212 	}
213 	if (!fgets(buf, sizeof(buf), stdin) || strcmp(buf, "end\n")) {
214 		warnx("%s: no \"end\" line.", filename);
215 		return(1);
216 	}
217 	return(0);
218 }
219 
220 static void
221 usage()
222 {
223 	(void)fprintf(stderr, "usage: %s [-p] [file ...]\n",
224 		      getprogname());
225 	exit(1);
226 }
227