usr.bin/from/from.c

   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. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * @(#) Copyright (c) 1980, 1988, 1993 The Regents of the University of California.  All rights reserved.
  30  * @(#)from.c   8.1 (Berkeley) 6/6/93
  31  * $FreeBSD: src/usr.bin/from/from.c,v 1.8.2.1 2000/10/06 08:19:19 ru Exp $
  32  */
  33
  34 #include <sys/param.h>
  35
  36 #include <ctype.h>
  37 #include <err.h>
  38 #include <pwd.h>
  39 #include <stdio.h>
  40 #include <stdlib.h>
  41 #include <paths.h>
  42 #include <string.h>
  43 #include <unistd.h>
  44
  45 static int      match(char *, char *);
  46 static void     usage(void);
  47
  48 int
  49 main(int argc, char **argv)
  50 {
  51         struct passwd *pwd;
  52         int ch, count, newline;
  53         const char *file;
  54         char *sender, *p;
  55 #if MAXPATHLEN > BUFSIZ
  56         char buf[MAXPATHLEN];
  57 #else
  58         char buf[BUFSIZ];
  59 #endif
  60
  61         file = sender = NULL;
  62         count = -1;
  63         while ((ch = getopt(argc, argv, "cf:s:")) != -1)
  64                 switch (ch) {
  65                 case 'c':
  66                         count = 0;
  67                         break;
  68                 case 'f':
  69                         file = optarg;
  70                         break;
  71                 case 's':
  72                         sender = optarg;
  73                         for (p = sender; *p; ++p)
  74                                 *p = tolower(*p);
  75                         break;
  76                 case '?':
  77                 default:
  78                         usage();
  79                 }
  80         argv += optind;
  81
  82         if (file == NULL) {
  83                 if (*argv) {
  84                         snprintf(buf, sizeof(buf), "%s/%s", _PATH_MAILDIR, *argv);
  85                         file  = buf;
  86                 } else {
  87                         if ((file = getenv("MAIL")) == NULL) {
  88                                 if (!(pwd = getpwuid(getuid())))
  89                                         errx(1, "no password file entry for you");
  90                                 file = pwd->pw_name;
  91                                 snprintf(buf, sizeof(buf),
  92                                     "%s/%s", _PATH_MAILDIR, file);
  93                                 file = buf;
  94                         }
  95                 }
  96         }
  97
  98         /* read from stdin */
  99         if (strcmp(file, "-") == 0) {
 100         }
 101         else if (freopen(file, "r", stdin) == NULL) {
 102                 err(1, "can't read %s", file);
 103         }
 104         for (newline = 1; fgets(buf, sizeof(buf), stdin);) {
 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         exit(0);
 122 }
 123
 124 static void
 125 usage(void)
 126 {
 127         fprintf(stderr, "usage: from [-c] [-f file] [-s sender] [user]\n");
 128         exit(1);
 129 }
 130
 131 static int
 132 match(char *line, char *sender)
 133 {
 134         char ch, pch, first, *p, *t;
 135
 136         for (first = *sender++;;) {
 137                 if (isspace(ch = *line))
 138                         return(0);
 139                 ++line;
 140                 ch = tolower(ch);
 141                 if (ch != first)
 142                         continue;
 143                 for (p = sender, t = line;;) {
 144                         if (!(pch = *p++))
 145                                 return(1);
 146                         ch = tolower(*t++);
 147                         if (ch != pch)
 148                                 break;
 149                 }
 150         }
 151         /* NOTREACHED */
 152 }