1 /* $NetBSD: from.c,v 1.17 2008/07/21 14:19:22 lukem Exp $ */
2
3 /*
4 * Copyright (c) 1980, 1988, 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 #include <sys/cdefs.h>
33 #ifndef lint
34 __COPYRIGHT("@(#) Copyright (c) 1980, 1988, 1993\
35 The Regents of the University of California. All rights reserved.");
36 #endif /* not lint */
37
38 #ifndef lint
39 #if 0
40 static char sccsid[] = "@(#)from.c 8.1 (Berkeley) 6/6/93";
41 #endif
42 __RCSID("$NetBSD: from.c,v 1.17 2008/07/21 14:19:22 lukem Exp $");
43 #endif /* not lint */
44
45 #include <sys/types.h>
46 #include <ctype.h>
47 #include <err.h>
48 #include <paths.h>
49 #include <pwd.h>
50 #include <stdio.h>
51 #include <stdlib.h>
52 #include <string.h>
53 #include <unistd.h>
54
55 int main (int, char **);
56 int match (const char *, const char *);
57
58 int
main(int argc,char ** argv)59 main(int argc, char **argv)
60 {
61 struct passwd *pwd;
62 int ch, newline;
63 char *file, *sender, *p;
64 #if MAXPATHLEN > BUFSIZ
65 char buf[MAXPATHLEN];
66 #else
67 char buf[BUFSIZ];
68 #endif
69
70 file = sender = NULL;
71 while ((ch = getopt(argc, argv, "f:s:")) != -1)
72 switch((char)ch) {
73 case 'f':
74 file = optarg;
75 break;
76 case 's':
77 sender = optarg;
78 for (p = sender; *p; ++p)
79 *p = tolower((unsigned char)*p);
80 break;
81 default:
82 fprintf(stderr, "usage: from [-f file] [-s sender] [user]\n");
83 exit(1);
84 }
85 argv += optind;
86
87 /*
88 * We find the mailbox by:
89 * 1 -f flag
90 * 2 user
91 * 2 MAIL environment variable
92 * 3 _PATH_MAILDIR/file
93 */
94 if (!file) {
95 if (!(file = *argv)) {
96 if (!(file = getenv("MAIL"))) {
97 if (!(pwd = getpwuid(getuid())))
98 errx(1, "no password file entry for you");
99 if ((file = getenv("LOGNAME")) != NULL ||
100 (file = getenv("USER")) != NULL) {
101 (void)snprintf(buf, sizeof(buf),
102 "%s/%s", _PATH_MAILDIR, file);
103 file = buf;
104 } else
105 (void)snprintf(file = buf, sizeof(buf),
106 "%s/%s",
107 _PATH_MAILDIR, pwd->pw_name);
108 }
109 } else {
110 (void)snprintf(buf, sizeof(buf), "%s/%s",
111 _PATH_MAILDIR, file);
112 file = buf;
113 }
114 }
115 if (!freopen(file, "r", stdin))
116 err(1, "can't read %s", file);
117
118 for (newline = 1; fgets(buf, sizeof(buf), stdin);) {
119 if (*buf == '\n') {
120 newline = 1;
121 continue;
122 }
123 if (newline && !strncmp(buf, "From ", 5) &&
124 (!sender || match(buf + 5, sender)))
125 printf("%s", buf);
126 newline = 0;
127 }
128 exit(0);
129 }
130
131 int
match(const char * line,const char * sender)132 match(const char *line, const char *sender)
133 {
134 char ch, pch, first;
135 const char *p, *t;
136
137 for (first = *sender++;;) {
138 if (isspace((unsigned char)(ch = *line)))
139 return(0);
140 ++line;
141 ch = tolower((unsigned char)ch);
142 if (ch != first)
143 continue;
144 for (p = sender, t = line;;) {
145 if (!(pch = *p++))
146 return(1);
147 ch = tolower((unsigned char)*t++);
148 if (ch != pch)
149 break;
150 }
151 }
152 /* NOTREACHED */
153 }
154