xref: /netbsd-src/usr.bin/uudecode/uudecode.c (revision 1ca5c1b28139779176bd5c13ad7c5f25c0bcd5f8)
1 /*	$NetBSD: uudecode.c,v 1.13 1999/03/23 05:59:09 cgd 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. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/cdefs.h>
37 #ifndef lint
38 __COPYRIGHT("@(#) Copyright (c) 1983, 1993\n\
39 	The Regents of the University of California.  All rights reserved.\n");
40 #endif
41 
42 #ifndef lint
43 #if 0
44 static char sccsid[] = "@(#)uudecode.c	8.2 (Berkeley) 4/2/94";
45 #endif
46 __RCSID("$NetBSD: uudecode.c,v 1.13 1999/03/23 05:59:09 cgd Exp $");
47 #endif /* not lint */
48 
49 /*
50  * uudecode [file ...]
51  *
52  * create the specified file, decoding as you go.
53  * used with uuencode.
54  */
55 #include <sys/param.h>
56 #include <sys/stat.h>
57 #include <err.h>
58 #include <errno.h>
59 #include <locale.h>
60 #include <pwd.h>
61 #include <stdio.h>
62 #include <string.h>
63 #include <unistd.h>
64 #include <ctype.h>
65 #include <stdlib.h>
66 #include <limits.h>
67 
68 static int decode __P((void));
69 static void usage __P((void));
70 int main __P((int, char **));
71 
72 int pflag;
73 char *filename;
74 
75 int
76 main(argc, argv)
77 	int argc;
78 	char *argv[];
79 {
80 	int ch, rval;
81 
82 	setlocale(LC_ALL, "");
83 
84 	pflag = 0;
85 	while ((ch = getopt(argc, argv, "p")) != -1)
86 		switch (ch) {
87 		case 'p':
88 			pflag = 1;
89 			break;
90 		default:
91 			usage();
92 		}
93 	argc -= optind;
94 	argv += optind;
95 
96 	if (*argv) {
97 		rval = 0;
98 		do {
99 			if (!freopen(filename = *argv, "r", stdin)) {
100 				warnx("%s", *argv);
101 				rval = 1;
102 				continue;
103 			}
104 			rval |= decode();
105 		} while (*++argv);
106 	} else {
107 		filename = "stdin";
108 		rval = decode();
109 	}
110 	exit(rval);
111 }
112 
113 static int
114 decode()
115 {
116 	struct passwd *pw;
117 	int n;
118 	char ch, *p;
119 	int n1;
120 	long mode;
121 	char *fn;
122 	char buf[MAXPATHLEN];
123 
124 	/* search for header line */
125 	do {
126 		if (!fgets(buf, sizeof(buf), stdin)) {
127 			warnx("%s: no \"begin\" line", filename);
128 			return(1);
129 		}
130 	} while (strncmp(buf, "begin ", 6));
131         /* must be followed by an octal mode and a space */
132 	mode = strtol(buf + 6, &fn, 8);
133 	if (fn == (buf+6) || !isspace(*fn) || mode==LONG_MIN || mode==LONG_MAX)
134 	{
135 	        warnx("%s: invalid mode on \"begin\" line\n", filename);
136 		return(1);
137 	}
138 	/* skip whitespace for file name */
139 	while (*fn && isspace(*fn)) fn++;
140 	if (*fn == 0) {
141                 warnx("%s: no filename on \"begin\" line\n", filename);
142 		return(1);
143 	}
144 	/* zap newline */
145 	for (p = fn; *p && *p != '\n'; p++)
146 	        ;
147 	if (*p) *p = 0;
148 
149 	/* handle ~user/file format */
150 	if (*fn == '~') {
151 		if (!(p = strchr(fn, '/'))) {
152 			warnx("%s: illegal ~user.", filename);
153 			return(1);
154 		}
155 		*p++ = '\0';
156 		if (!(pw = getpwnam(fn + 1))) {
157 			warnx("%s: no user %s.", filename, buf);
158 			return(1);
159 		}
160 		n = strlen(pw->pw_dir);
161 		n1 = strlen(p);
162 		if (n + n1 + 2 > MAXPATHLEN) {
163 			warnx("%s: path too long.", filename);
164 			return(1);
165 		}
166 		/* make space at beginning of buf by moving end of pathname */
167 		memmove(buf + n + 1, p, n1 + 1);
168 		memmove(buf, pw->pw_dir, n);
169 		buf[n] = '/';
170 		fn = buf;
171 	}
172 
173 	/* create output file, set mode */
174 	if (!pflag && (!freopen(fn, "w", stdout) ||
175 	    fchmod(fileno(stdout), mode & 0666))) {
176 		warnx("%s: %s", fn, filename);
177 		return(1);
178 	}
179 
180 	/* for each input line */
181 	for (;;) {
182 		if (!fgets(p = buf, sizeof(buf), stdin)) {
183 			warnx("%s: short file.", filename);
184 			return(1);
185 		}
186 #define	DEC(c)	(((c) - ' ') & 077)		/* single character decode */
187 		/*
188 		 * `n' is used to avoid writing out all the characters
189 		 * at the end of the file.
190 		 */
191 		if ((n = DEC(*p)) <= 0)
192 			break;
193 		for (++p; n > 0; p += 4, n -= 3)
194 			if (n >= 3) {
195 				ch = DEC(p[0]) << 2 | DEC(p[1]) >> 4;
196 				putchar(ch);
197 				ch = DEC(p[1]) << 4 | DEC(p[2]) >> 2;
198 				putchar(ch);
199 				ch = DEC(p[2]) << 6 | DEC(p[3]);
200 				putchar(ch);
201 			}
202 			else {
203 				if (n >= 1) {
204 					ch = DEC(p[0]) << 2 | DEC(p[1]) >> 4;
205 					putchar(ch);
206 				}
207 				if (n >= 2) {
208 					ch = DEC(p[1]) << 4 | DEC(p[2]) >> 2;
209 					putchar(ch);
210 				}
211 				if (n >= 3) {
212 					ch = DEC(p[2]) << 6 | DEC(p[3]);
213 					putchar(ch);
214 				}
215 			}
216 	}
217 	if (!fgets(buf, sizeof(buf), stdin) || strcmp(buf, "end\n")) {
218 		warnx("%s: no \"end\" line.", filename);
219 		return(1);
220 	}
221 	return(0);
222 }
223 
224 static void
225 usage()
226 {
227 	(void)fprintf(stderr, "usage: uudecode [-p] [file ...]\n");
228 	exit(1);
229 }
230