xref: /titanic_50/usr/src/ucbcmd/from/from.c (revision 7c478bd95313f5f23a4c958a745db2134aa03244)
1 /*
2  * Copyright 1994 Sun Microsystems, Inc.  All rights reserved.
3  * Use is subject to license terms.
4  */
5 
6 /*
7  * Copyright (c) 1980 Regents of the University of California.
8  * All rights reserved.  The Berkeley software License Agreement
9  * specifies the terms and conditions for redistribution.
10  */
11 
12 #pragma ident	"%Z%%M%	%I%	%E% SMI"
13 
14 #include <stdio.h>
15 #include <sys/types.h>
16 #include <unistd.h>
17 #include <stdlib.h>
18 #include <ctype.h>
19 #include <pwd.h>
20 #include <sys/param.h>
21 #include <string.h>
22 
23 static int match(char *, char *);
24 
25 main(argc, argv)
26 	int argc;
27 	register char **argv;
28 {
29 	char lbuf[BUFSIZ];
30 	char lbuf2[BUFSIZ];
31 	register struct passwd *pp;
32 	int stashed = 0;
33 	register char *name;
34 	char *sender = NULL;
35 	char mailbox[MAXPATHLEN];
36 	char *tmp_mailbox;
37 	extern char *optarg;
38 	extern int optind;
39 	extern int opterr;
40 	int c;
41 	int errflg = 0;
42 
43 	opterr = 0;
44 	while ((c = getopt(argc, argv, "s:")) != EOF)
45 		switch (c) {
46 		case 's':
47 			sender = optarg;
48 			for (name = sender; *name; name++)
49 				if (isupper(*name))
50 					*name = tolower(*name);
51 			break;
52 		case '?':
53 			errflg++;
54 			break;
55 		}
56 	if (errflg) {
57 		(void) fprintf(stderr,
58 			    "Usage: from [-s sender] [user]\n");
59 		exit(1);
60 	}
61 
62 	if (optind < argc) {
63 		(void) sprintf(mailbox, "/var/mail/%s", argv[optind]);
64 	} else {
65 		if (tmp_mailbox = getenv("MAIL")) {
66 			(void) strcpy(mailbox, tmp_mailbox);
67 		} else {
68 			name = getlogin();
69 			if (name == NULL || strlen(name) == 0) {
70 				pp = getpwuid(getuid());
71 				if (pp == NULL) {
72 					(void) fprintf(stderr,
73 					    "Who are you?\n");
74 					exit(1);
75 				}
76 				name = pp->pw_name;
77 			}
78 			(void) sprintf(mailbox, "/var/mail/%s", name);
79 		}
80 	}
81 	if (freopen(mailbox, "r", stdin) == NULL) {
82 		(void) fprintf(stderr, "Can't open %s\n", mailbox);
83 		exit(0);
84 	}
85 	while (fgets(lbuf, sizeof (lbuf), stdin) != NULL)
86 		if (lbuf[0] == '\n' && stashed) {
87 			stashed = 0;
88 			(void) printf("%s", lbuf2);
89 		} else if (strncmp(lbuf, "From ", 5) == 0 &&
90 		    (sender == NULL || match(&lbuf[4], sender))) {
91 			(void) strcpy(lbuf2, lbuf);
92 			stashed = 1;
93 		}
94 	if (stashed)
95 		(void) printf("%s", lbuf2);
96 	return(0);
97 }
98 
99 static int
100 match(line, str)
101 	register char *line, *str;
102 {
103 	register char ch;
104 
105 	while (*line == ' ' || *line == '\t')
106 		++line;
107 	if (*line == '\n')
108 		return (0);
109 	while (*str && *line != ' ' && *line != '\t' && *line != '\n') {
110 		ch = isupper(*line) ? tolower(*line) : *line;
111 		if (ch != *str++)
112 			return (0);
113 		line++;
114 	}
115 	return (*str == '\0');
116 }
117