1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1990, 1993, 1994
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__FBSDID("$FreeBSD$");
34__SCCSID("@(#)pty.c	8.3 (Berkeley) 5/16/94");
35
36#include <sys/types.h>
37#include <sys/ioctl.h>
38#include <sys/stat.h>
39
40#include <errno.h>
41#include <fcntl.h>
42#include <grp.h>
43#include <libutil.h>
44#include <stdlib.h>
45#include <string.h>
46#include <termios.h>
47#include <unistd.h>
48
49int
50openpty(int *amaster, int *aslave, char *name, struct termios *termp,
51    struct winsize *winp)
52{
53	const char *slavename;
54	int master, slave;
55
56	master = posix_openpt(O_RDWR|O_NOCTTY);
57	if (master == -1)
58		return (-1);
59
60	if (grantpt(master) == -1)
61		goto bad;
62
63	if (unlockpt(master) == -1)
64		goto bad;
65
66	slavename = ptsname(master);
67	if (slavename == NULL)
68		goto bad;
69
70	slave = open(slavename, O_RDWR);
71	if (slave == -1)
72		goto bad;
73
74	*amaster = master;
75	*aslave = slave;
76
77	if (name)
78		strcpy(name, slavename);
79	if (termp)
80		tcsetattr(slave, TCSAFLUSH, termp);
81	if (winp)
82		ioctl(slave, TIOCSWINSZ, (char *)winp);
83
84	return (0);
85
86bad:	close(master);
87	return (-1);
88}
89
90int
91forkpty(int *amaster, char *name, struct termios *termp, struct winsize *winp)
92{
93	int master, slave, pid;
94
95	if (openpty(&master, &slave, name, termp, winp) == -1)
96		return (-1);
97	switch (pid = fork()) {
98	case -1:
99		(void)close(slave);
100		return (-1);
101	case 0:
102		/*
103		 * child
104		 */
105		(void)close(master);
106		login_tty(slave);
107		return (0);
108	}
109	/*
110	 * parent
111	 */
112	*amaster = master;
113	(void) close(slave);
114	return (pid);
115}
116