Fix concurrent changes on nscd aware files (BZ #23178)
[glibc.git] / bits / wchar.h
blob5fa6ccd4afe8ac8d6ae41b75c8ca49a8bf3e311a
1 /* wchar_t type related definitions.
2 Copyright (C) 2000-2018 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <http://www.gnu.org/licenses/>. */
19 #ifndef _BITS_WCHAR_H
20 #define _BITS_WCHAR_H 1
22 /* The fallback definitions, for when __WCHAR_MAX__ or __WCHAR_MIN__
23 are not defined, give the right value and type as long as both int
24 and wchar_t are 32-bit types. Adding L'\0' to a constant value
25 ensures that the type is correct; it is necessary to use (L'\0' +
26 0) rather than just L'\0' so that the type in C++ is the promoted
27 version of wchar_t rather than the distinct wchar_t type itself.
28 Because wchar_t in preprocessor #if expressions is treated as
29 intmax_t or uintmax_t, the expression (L'\0' - 1) would have the
30 wrong value for WCHAR_MAX in such expressions and so cannot be used
31 to define __WCHAR_MAX in the unsigned case. */
33 #ifdef __WCHAR_MAX__
34 # define __WCHAR_MAX __WCHAR_MAX__
35 #elif L'\0' - 1 > 0
36 # define __WCHAR_MAX (0xffffffffu + L'\0')
37 #else
38 # define __WCHAR_MAX (0x7fffffff + L'\0')
39 #endif
41 #ifdef __WCHAR_MIN__
42 # define __WCHAR_MIN __WCHAR_MIN__
43 #elif L'\0' - 1 > 0
44 # define __WCHAR_MIN (L'\0' + 0)
45 #else
46 # define __WCHAR_MIN (-__WCHAR_MAX - 1)
47 #endif
49 #endif /* bits/wchar.h */