limits.h revision 263508
1/*===---- limits.h - Standard header for integer sizes --------------------===*\
2 *
3 * Copyright (c) 2009 Chris Lattner
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a copy
6 * of this software and associated documentation files (the "Software"), to deal
7 * in the Software without restriction, including without limitation the rights
8 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
9 * copies of the Software, and to permit persons to whom the Software is
10 * furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be included in
13 * all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
21 * THE SOFTWARE.
22 *
23\*===----------------------------------------------------------------------===*/
24
25#ifndef __CLANG_LIMITS_H
26#define __CLANG_LIMITS_H
27
28/* The system's limits.h may, in turn, try to #include_next GCC's limits.h.
29   Avert this #include_next madness. */
30#if defined __GNUC__ && !defined _GCC_LIMITS_H_
31#define _GCC_LIMITS_H_
32#endif
33
34/* System headers include a number of constants from POSIX in <limits.h>.
35   Include it if we're hosted. */
36#if __STDC_HOSTED__ && \
37    defined(__has_include_next) && __has_include_next(<limits.h>)
38#include_next <limits.h>
39#endif
40
41/* Many system headers try to "help us out" by defining these.  No really, we
42   know how big each datatype is. */
43#undef  SCHAR_MIN
44#undef  SCHAR_MAX
45#undef  UCHAR_MAX
46#undef  SHRT_MIN
47#undef  SHRT_MAX
48#undef  USHRT_MAX
49#undef  INT_MIN
50#undef  INT_MAX
51#undef  UINT_MAX
52#undef  LONG_MIN
53#undef  LONG_MAX
54#undef  ULONG_MAX
55
56#undef  CHAR_BIT
57#undef  CHAR_MIN
58#undef  CHAR_MAX
59
60/* C90/99 5.2.4.2.1 */
61#define SCHAR_MAX __SCHAR_MAX__
62#define SHRT_MAX  __SHRT_MAX__
63#define INT_MAX   __INT_MAX__
64#define LONG_MAX  __LONG_MAX__
65
66#define SCHAR_MIN (-__SCHAR_MAX__-1)
67#define SHRT_MIN  (-__SHRT_MAX__ -1)
68#define INT_MIN   (-__INT_MAX__  -1)
69#define LONG_MIN  (-__LONG_MAX__ -1L)
70
71#define UCHAR_MAX (__SCHAR_MAX__*2  +1)
72#define USHRT_MAX (__SHRT_MAX__ *2  +1)
73#define UINT_MAX  (__INT_MAX__  *2U +1U)
74#define ULONG_MAX (__LONG_MAX__ *2UL+1UL)
75
76#ifndef MB_LEN_MAX
77#define MB_LEN_MAX 1
78#endif
79
80#define CHAR_BIT  __CHAR_BIT__
81
82#ifdef __CHAR_UNSIGNED__  /* -funsigned-char */
83#define CHAR_MIN 0
84#define CHAR_MAX UCHAR_MAX
85#else
86#define CHAR_MIN SCHAR_MIN
87#define CHAR_MAX __SCHAR_MAX__
88#endif
89
90/* C99 5.2.4.2.1: Added long long.
91   C++11 18.3.3.2: same contents as the Standard C Library header <limits.h>.
92 */
93#if __STDC_VERSION__ >= 199901 || __cplusplus >= 201103L
94
95#undef  LLONG_MIN
96#undef  LLONG_MAX
97#undef  ULLONG_MAX
98
99#define LLONG_MAX  __LONG_LONG_MAX__
100#define LLONG_MIN  (-__LONG_LONG_MAX__-1LL)
101#define ULLONG_MAX (__LONG_LONG_MAX__*2ULL+1ULL)
102#endif
103
104/* LONG_LONG_MIN/LONG_LONG_MAX/ULONG_LONG_MAX are a GNU extension.  It's too bad
105   that we don't have something like #pragma poison that could be used to
106   deprecate a macro - the code should just use LLONG_MAX and friends.
107 */
108#if defined(__GNU_LIBRARY__) ? defined(__USE_GNU) : !defined(__STRICT_ANSI__)
109
110#undef   LONG_LONG_MIN
111#undef   LONG_LONG_MAX
112#undef   ULONG_LONG_MAX
113
114#define LONG_LONG_MAX  __LONG_LONG_MAX__
115#define LONG_LONG_MIN  (-__LONG_LONG_MAX__-1LL)
116#define ULONG_LONG_MAX (__LONG_LONG_MAX__*2ULL+1ULL)
117#endif
118
119#endif /* __CLANG_LIMITS_H */
120