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 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 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