1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22/*
23 * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27/*	Copyright (c) 1988 AT&T	*/
28/*	  All Rights Reserved  	*/
29
30#include "lint.h"
31#include <sys/mkdev.h>
32#include <limits.h>
33#include <stdarg.h>
34#include <unistd.h>
35#include <strings.h>
36#include <errno.h>
37#include <sys/stat.h>
38#include <sys/fcntl.h>
39#include <sys/stropts.h>
40#include <sys/stream.h>
41#include <sys/ptms.h>
42#include <sys/syscall.h>
43#include "libc.h"
44
45static int xpg4_fixup(int fd);
46static void push_module(int fd);
47static int isptsfd(int fd);
48static void itoa(int i, char *ptr);
49
50int
51__openat(int dfd, const char *path, int oflag, mode_t mode)
52{
53	int fd = syscall(SYS_openat, dfd, path, oflag, mode);
54	return (xpg4_fixup(fd));
55}
56
57int
58__open(const char *path, int oflag, mode_t mode)
59{
60#if defined(_RETAIN_OLD_SYSCALLS)
61	int fd = syscall(SYS_open, path, oflag, mode);
62	return (xpg4_fixup(fd));
63#else
64	return (__openat(AT_FDCWD, path, oflag, mode));
65#endif
66}
67
68#if !defined(_LP64)
69
70int
71__openat64(int dfd, const char *path, int oflag, mode_t mode)
72{
73	int fd = syscall(SYS_openat64, dfd, path, oflag, mode);
74	return (xpg4_fixup(fd));
75}
76
77int
78__open64(const char *path, int oflag, mode_t mode)
79{
80#if defined(_RETAIN_OLD_SYSCALLS)
81	int fd = syscall(SYS_open64, path, oflag, mode);
82	return (xpg4_fixup(fd));
83#else
84	return (__openat64(AT_FDCWD, path, oflag, mode));
85#endif
86}
87
88#endif	/* !_LP64 */
89
90/*
91 * XPG4v2 requires that open of a slave pseudo terminal device
92 * provides the process with an interface that is identical to
93 * the terminal interface. For a more detailed discussion,
94 * see bugid 4025044.
95 */
96static int
97xpg4_fixup(int fd)
98{
99	if (libc__xpg4 != 0 && fd >= 0 && isptsfd(fd))
100		push_module(fd);
101	return (fd);
102}
103
104/*
105 * Check if the file matches an entry in the /dev/pts directory.
106 * Be careful to preserve errno.
107 */
108static int
109isptsfd(int fd)
110{
111	char buf[TTYNAME_MAX];
112	char *str1 = buf;
113	const char *str2 = "/dev/pts/";
114	struct stat64 fsb, stb;
115	int oerrno = errno;
116	int rval = 0;
117
118	if (fstat64(fd, &fsb) == 0 && S_ISCHR(fsb.st_mode)) {
119		/*
120		 * Do this without strcpy() or strlen(),
121		 * to avoid invoking the dynamic linker.
122		 */
123		while (*str2 != '\0')
124			*str1++ = *str2++;
125		/*
126		 * Inline version of minor(dev), to avoid the dynamic linker.
127		 */
128		itoa(fsb.st_rdev & MAXMIN, str1);
129		if (stat64(buf, &stb) == 0)
130			rval = (stb.st_rdev == fsb.st_rdev);
131	}
132	errno = oerrno;
133	return (rval);
134}
135
136/*
137 * Converts a number to a string (null terminated).
138 */
139static void
140itoa(int i, char *ptr)
141{
142	int dig = 0;
143	int tempi;
144
145	tempi = i;
146	do {
147		dig++;
148		tempi /= 10;
149	} while (tempi);
150
151	ptr += dig;
152	*ptr = '\0';
153	while (--dig >= 0) {
154		*(--ptr) = i % 10 + '0';
155		i /= 10;
156	}
157}
158
159/*
160 * Push modules to provide tty semantics
161 */
162static void
163push_module(int fd)
164{
165	struct strioctl istr;
166	int oerrno = errno;
167
168	istr.ic_cmd = PTSSTTY;
169	istr.ic_len = 0;
170	istr.ic_timout = 0;
171	istr.ic_dp = NULL;
172	if (ioctl(fd, I_STR, &istr) != -1) {
173		(void) ioctl(fd, __I_PUSH_NOCTTY, "ptem");
174		(void) ioctl(fd, __I_PUSH_NOCTTY, "ldterm");
175		(void) ioctl(fd, __I_PUSH_NOCTTY, "ttcompat");
176		istr.ic_cmd = PTSSTTY;
177		istr.ic_len = 0;
178		istr.ic_timout = 0;
179		istr.ic_dp = NULL;
180		(void) ioctl(fd, I_STR, &istr);
181	}
182	errno = oerrno;
183}
184