1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
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/types.h>
33 #include <ctype.h>
34 #include <err.h>
35 #include <pwd.h>
36 #include <stdio.h>
37 #include <stdlib.h>
38 #include <paths.h>
39 #include <string.h>
40 #include <unistd.h>
41
42 static int match(const char *, const char *);
43 static void usage(void) __dead2;
44
45 int
main(int argc,char ** argv)46 main(int argc, char **argv)
47 {
48 FILE *mbox;
49 struct passwd *pwd;
50 int ch, count, newline;
51 const char *file;
52 char *sender, *p;
53 #if MAXPATHLEN > BUFSIZ
54 char buf[MAXPATHLEN];
55 #else
56 char buf[BUFSIZ];
57 #endif
58
59 file = sender = NULL;
60 count = -1;
61 while ((ch = getopt(argc, argv, "cf:s:")) != -1)
62 switch (ch) {
63 case 'c':
64 count = 0;
65 break;
66 case 'f':
67 file = optarg;
68 break;
69 case 's':
70 sender = optarg;
71 for (p = sender; *p; ++p)
72 *p = tolower(*p);
73 break;
74 case '?':
75 default:
76 usage();
77 }
78 argc -= optind;
79 argv += optind;
80
81 if (file == NULL) {
82 if (argc) {
83 (void)snprintf(buf, sizeof(buf), "%s/%s", _PATH_MAILDIR, *argv);
84 file = buf;
85 } else {
86 if (!(file = getenv("MAIL"))) {
87 if (!(pwd = getpwuid(getuid())))
88 errx(1, "no password file entry for you");
89 file = pwd->pw_name;
90 (void)snprintf(buf, sizeof(buf),
91 "%s/%s", _PATH_MAILDIR, file);
92 file = buf;
93 }
94 }
95 }
96
97 /* read from stdin */
98 if (strcmp(file, "-") == 0) {
99 mbox = stdin;
100 }
101 else if ((mbox = fopen(file, "r")) == NULL) {
102 errx(1, "can't read %s", file);
103 }
104 for (newline = 1; fgets(buf, sizeof(buf), mbox);) {
105 if (*buf == '\n') {
106 newline = 1;
107 continue;
108 }
109 if (newline && !strncmp(buf, "From ", 5) &&
110 (!sender || match(buf + 5, sender))) {
111 if (count != -1)
112 count++;
113 else
114 printf("%s", buf);
115 }
116 newline = 0;
117 }
118 if (count != -1)
119 printf("There %s %d message%s in your incoming mailbox.\n",
120 count == 1 ? "is" : "are", count, count == 1 ? "" : "s");
121 fclose(mbox);
122 exit(0);
123 }
124
125 static void
usage(void)126 usage(void)
127 {
128 fprintf(stderr, "usage: from [-c] [-f file] [-s sender] [user]\n");
129 exit(1);
130 }
131
132 static int
match(const char * line,const char * sender)133 match(const char *line, const char *sender)
134 {
135 char ch, pch, first;
136 const char *p, *t;
137
138 for (first = *sender++;;) {
139 if (isspace(ch = *line))
140 return(0);
141 ++line;
142 ch = tolower(ch);
143 if (ch != first)
144 continue;
145 for (p = sender, t = line;;) {
146 if (!(pch = *p++))
147 return(1);
148 ch = tolower(*t);
149 t++;
150 if (ch != pch)
151 break;
152 }
153 }
154 /* NOTREACHED */
155 }
156