xref: /dragonfly/usr.bin/from/from.c (revision 2cd2d2b5)
1 /*
2  * Copyright (c) 1980, 1988, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * @(#) Copyright (c) 1980, 1988, 1993 The Regents of the University of California.  All rights reserved.
34  * @(#)from.c	8.1 (Berkeley) 6/6/93
35  * $FreeBSD: src/usr.bin/from/from.c,v 1.8.2.1 2000/10/06 08:19:19 ru Exp $
36  * $DragonFly: src/usr.bin/from/from.c,v 1.3 2003/10/04 20:36:44 hmp Exp $
37  */
38 
39 #include <sys/types.h>
40 #include <ctype.h>
41 #include <err.h>
42 #include <pwd.h>
43 #include <stdio.h>
44 #include <stdlib.h>
45 #include <paths.h>
46 #include <string.h>
47 #include <unistd.h>
48 
49 int match(char *, char *);
50 static void usage(void);
51 
52 int
53 main(int argc, char **argv)
54 {
55 	struct passwd *pwd;
56 	int ch, count, newline;
57 	char *file, *sender, *p;
58 #if MAXPATHLEN > BUFSIZ
59 	char buf[MAXPATHLEN];
60 #else
61 	char buf[BUFSIZ];
62 #endif
63 
64 	file = sender = NULL;
65 	count = -1;
66 	while ((ch = getopt(argc, argv, "cf:s:")) != -1)
67 		switch (ch) {
68 		case 'c':
69 			count = 0;
70 			break;
71 		case 'f':
72 			file = optarg;
73 			break;
74 		case 's':
75 			sender = optarg;
76 			for (p = sender; *p; ++p)
77 				if (isupper(*p))
78 					*p = tolower(*p);
79 			break;
80 		case '?':
81 		default:
82 			usage();
83 		}
84 	argv += optind;
85 
86 	if (!file) {
87 		if (*argv) {
88 			(void)snprintf(buf, sizeof(buf), "%s/%s", _PATH_MAILDIR, *argv);
89 			file  = buf;
90 		} else {
91 			if (!(file = getenv("MAIL"))) {
92 				if (!(pwd = getpwuid(getuid())))
93 					errx(1, "no password file entry for you");
94 				file = pwd->pw_name;
95 				(void)snprintf(buf, sizeof(buf),
96 				    "%s/%s", _PATH_MAILDIR, file);
97 				file = buf;
98 			}
99 		}
100 	}
101 
102 	/* read from stdin */
103 	if (strcmp(file, "-") == 0) {
104 	}
105 	else if (!freopen(file, "r", stdin)) {
106 		errx(1, "can't read %s", file);
107 	}
108 	for (newline = 1; fgets(buf, sizeof(buf), stdin);) {
109 		if (*buf == '\n') {
110 			newline = 1;
111 			continue;
112 		}
113 		if (newline && !strncmp(buf, "From ", 5) &&
114 		    (!sender || match(buf + 5, sender))) {
115 			if (count != -1)
116 				count++;
117 			else
118 				printf("%s", buf);
119 		}
120 		newline = 0;
121 	}
122 	if (count != -1)
123 		printf("There %s %d message%s in your incoming mailbox.\n",
124 		    count == 1 ? "is" : "are", count, count == 1 ? "" : "s");
125 	exit(0);
126 }
127 
128 static void
129 usage(void)
130 {
131 	fprintf(stderr, "usage: from [-c] [-f file] [-s sender] [user]\n");
132 	exit(1);
133 }
134 
135 int
136 match(register char *line, register char *sender)
137 {
138 	register char ch, pch, first, *p, *t;
139 
140 	for (first = *sender++;;) {
141 		if (isspace(ch = *line))
142 			return(0);
143 		++line;
144 		if (isupper(ch))
145 			ch = tolower(ch);
146 		if (ch != first)
147 			continue;
148 		for (p = sender, t = line;;) {
149 			if (!(pch = *p++))
150 				return(1);
151 			if (isupper(ch = *t++))
152 				ch = tolower(ch);
153 			if (ch != pch)
154 				break;
155 		}
156 	}
157 	/* NOTREACHED */
158 }
159