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