NetBSD/usr.bin/from/from.c

154 lines
4.1 KiB
C

/* $NetBSD: from.c,v 1.17 2008/07/21 14:19:22 lukem Exp $ */
/*
* Copyright (c) 1980, 1988, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
#ifndef lint
__COPYRIGHT("@(#) Copyright (c) 1980, 1988, 1993\
The Regents of the University of California. All rights reserved.");
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)from.c 8.1 (Berkeley) 6/6/93";
#endif
__RCSID("$NetBSD: from.c,v 1.17 2008/07/21 14:19:22 lukem Exp $");
#endif /* not lint */
#include <sys/types.h>
#include <ctype.h>
#include <err.h>
#include <paths.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
int main (int, char **);
int match (const char *, const char *);
int
main(int argc, char **argv)
{
struct passwd *pwd;
int ch, newline;
char *file, *sender, *p;
#if MAXPATHLEN > BUFSIZ
char buf[MAXPATHLEN];
#else
char buf[BUFSIZ];
#endif
file = sender = NULL;
while ((ch = getopt(argc, argv, "f:s:")) != -1)
switch((char)ch) {
case 'f':
file = optarg;
break;
case 's':
sender = optarg;
for (p = sender; *p; ++p)
*p = tolower((unsigned char)*p);
break;
default:
fprintf(stderr, "usage: from [-f file] [-s sender] [user]\n");
exit(1);
}
argv += optind;
/*
* We find the mailbox by:
* 1 -f flag
* 2 user
* 2 MAIL environment variable
* 3 _PATH_MAILDIR/file
*/
if (!file) {
if (!(file = *argv)) {
if (!(file = getenv("MAIL"))) {
if (!(pwd = getpwuid(getuid())))
errx(1, "no password file entry for you");
if ((file = getenv("LOGNAME")) != NULL ||
(file = getenv("USER")) != NULL) {
(void)snprintf(buf, sizeof(buf),
"%s/%s", _PATH_MAILDIR, file);
file = buf;
} else
(void)snprintf(file = buf, sizeof(buf),
"%s/%s",
_PATH_MAILDIR, pwd->pw_name);
}
} else {
(void)snprintf(buf, sizeof(buf), "%s/%s",
_PATH_MAILDIR, file);
file = buf;
}
}
if (!freopen(file, "r", stdin))
err(1, "can't read %s", file);
for (newline = 1; fgets(buf, sizeof(buf), stdin);) {
if (*buf == '\n') {
newline = 1;
continue;
}
if (newline && !strncmp(buf, "From ", 5) &&
(!sender || match(buf + 5, sender)))
printf("%s", buf);
newline = 0;
}
exit(0);
}
int
match(const char *line, const char *sender)
{
char ch, pch, first;
const char *p, *t;
for (first = *sender++;;) {
if (isspace((unsigned char)(ch = *line)))
return(0);
++line;
ch = tolower((unsigned char)ch);
if (ch != first)
continue;
for (p = sender, t = line;;) {
if (!(pch = *p++))
return(1);
ch = tolower((unsigned char)*t++);
if (ch != pch)
break;
}
}
/* NOTREACHED */
}