freebsd-dev/usr.bin/tee/tee.c
2021-09-15 11:04:24 +00:00

161 lines
4.2 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 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.
*/
#ifndef lint
static const char copyright[] =
"@(#) Copyright (c) 1988, 1993\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)tee.c 8.1 (Berkeley) 6/6/93";
#endif
static const char rcsid[] =
"$FreeBSD$";
#endif /* not lint */
#include <sys/capsicum.h>
#include <sys/queue.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <capsicum_helpers.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
struct entry {
int fd;
const char *name;
STAILQ_ENTRY(entry) entries;
};
static STAILQ_HEAD(, entry) head = STAILQ_HEAD_INITIALIZER(head);
static void add(int, const char *);
static void usage(void);
int
main(int argc, char *argv[])
{
struct entry *p;
int n, fd, rval, wval;
char *bp;
int append, ch, exitval;
char *buf;
#define BSIZE (8 * 1024)
append = 0;
while ((ch = getopt(argc, argv, "ai")) != -1)
switch((char)ch) {
case 'a':
append = 1;
break;
case 'i':
(void)signal(SIGINT, SIG_IGN);
break;
case '?':
default:
usage();
}
argv += optind;
argc -= optind;
if ((buf = malloc(BSIZE)) == NULL)
err(1, "malloc");
if (caph_limit_stdin() == -1 || caph_limit_stderr() == -1)
err(EXIT_FAILURE, "unable to limit stdio");
add(STDOUT_FILENO, "stdout");
for (exitval = 0; *argv; ++argv)
if ((fd = open(*argv, append ? O_WRONLY|O_CREAT|O_APPEND :
O_WRONLY|O_CREAT|O_TRUNC, DEFFILEMODE)) < 0) {
warn("%s", *argv);
exitval = 1;
} else
add(fd, *argv);
if (caph_enter() < 0)
err(EXIT_FAILURE, "unable to enter capability mode");
while ((rval = read(STDIN_FILENO, buf, BSIZE)) > 0)
STAILQ_FOREACH(p, &head, entries) {
n = rval;
bp = buf;
do {
if ((wval = write(p->fd, bp, n)) == -1) {
warn("%s", p->name);
exitval = 1;
break;
}
bp += wval;
} while (n -= wval);
}
if (rval < 0)
err(1, "read");
exit(exitval);
}
static void
usage(void)
{
(void)fprintf(stderr, "usage: tee [-ai] [file ...]\n");
exit(1);
}
static void
add(int fd, const char *name)
{
struct entry *p;
cap_rights_t rights;
if (fd == STDOUT_FILENO) {
if (caph_limit_stdout() == -1)
err(EXIT_FAILURE, "unable to limit stdout");
} else {
cap_rights_init(&rights, CAP_WRITE, CAP_FSTAT);
if (caph_rights_limit(fd, &rights) < 0)
err(EXIT_FAILURE, "unable to limit rights");
}
if ((p = malloc(sizeof(struct entry))) == NULL)
err(1, "malloc");
p->fd = fd;
p->name = name;
STAILQ_INSERT_HEAD(&head, p, entries);
}