1/* Copyright (C) 2016-2020 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public License as
6 published by the Free Software Foundation; either version 2.1 of the
7 License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; see the file COPYING.LIB. If
16 not, see <https://www.gnu.org/licenses/>. */
17
18#include <unistd.h>
19#include <stdbool.h>
20#include <sys/sysmacros.h>
21#include <sys/types.h>
22#include <sys/stat.h>
23
24/* Return true if this is a UNIX98 pty device, as defined in
25 linux/Documentation/devices.txt (on linux < 4.10) or
26 linux/Documentation/admin-guide/devices.txt (on linux >= 4.10). */
27static inline bool
28is_pty (struct stat64 *sb)
29{
30#ifdef _STATBUF_ST_RDEV
31 int m = __gnu_dev_major (sb->st_rdev);
32 return (136 <= m && m <= 143);
33#else
34 return false;
35#endif
36}
37
38static inline bool
39is_mytty (const struct stat64 *mytty, const struct stat64 *maybe)
40{
41 return (maybe->st_ino == mytty->st_ino
42 && maybe->st_dev == mytty->st_dev
43#ifdef _STATBUF_ST_RDEV
44 && S_ISCHR (maybe->st_mode)
45 && maybe->st_rdev == mytty->st_rdev
46#endif
47 );
48}
49