limits.h

   1 /* Copyright (C) 1991, 1992 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 Library General Public License as
   6 published by the Free Software Foundation; either version 2 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 Library General Public License for more details.
  13
  14 You should have received a copy of the GNU Library General Public
  15 License along with the GNU C Library; see the file COPYING.LIB.  If
  16 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  17 Cambridge, MA 02139, USA.  */
  18
  19 /*
  20  *      ANSI Standard: 4.14/2.2.4.2 Limits of integral types    <limits.h>
  21  */
  22
  23 #include <features.h>
  24
  25 #ifdef  __USE_POSIX
  26 /* POSIX adds things to <limits.h>.  */
  27 #include <posix1_lim.h>
  28 #endif
  29
  30 #ifdef  __USE_POSIX2
  31 #include <posix2_lim.h>
  32 #endif
  33
  34
  35 #if     __GNUC__ >= 2
  36
  37  /* Get the compiler's limits.h, which defines all the ANSI constants.  */
  38  #ifndef _LIBC_LIMITS_H_
  39  #define _LIBC_LIMITS_H_        /* This tells it not to look for another.  */
  40  #endif
  41  #ifndef _GCC_LIMITS_H_         /* This is what GCC's file defines.  */
  42  #include_next <limits.h>
  43  #endif
  44
  45 #else   /* Not GCC 2.  */
  46
  47 /* We only protect from multiple inclusion here, because all the other
  48    #include's protect themselves, and in GCC 2 we may #include_next through
  49    multiple copies of this file before we get to GCC's.  */
  50 #ifndef _LIMITS_H
  51 #define _LIMITS_H
  52
  53 /* We don't have #include_next.
  54    Define ANSI <limits.h> for standard 32-bit words.  */
  55
  56 /* These assume 8-bit `char's, 16-bit `short int's,
  57    and 32-bit `int's and `long int's.  */
  58
  59 /* Number of bits in a `char'.  */
  60 #define CHAR_BIT        8
  61
  62 /* Maximum length of any multibyte character in any locale.
  63    Locale-writers should change this as necessary.  */
  64 #define MB_LEN_MAX      1
  65
  66 /* Minimum and maximum values a `signed char' can hold.  */
  67 #define SCHAR_MIN       (-128)
  68 #define SCHAR_MAX       127
  69
  70 /* Maximum value an `unsigned char' can hold.  (Minimum is 0.)  */
  71 #ifdef  __STDC__
  72 #define UCHAR_MAX       255U
  73 #else
  74 #define UCHAR_MAX       255
  75 #endif
  76
  77 /* Minimum and maximum values a `char' can hold.  */
  78 #ifdef __CHAR_UNSIGNED__
  79 #define CHAR_MIN        0
  80 #define CHAR_MAX        UCHAR_MAX
  81 #else
  82 #define CHAR_MIN        SCHAR_MIN
  83 #define CHAR_MAX        SCHAR_MAX
  84 #endif
  85
  86 /* Minimum and maximum values a `signed short int' can hold.  */
  87 #define SHRT_MIN        (-32768)
  88 #define SHRT_MAX        32767
  89
  90 /* Maximum value an `unsigned short int' can hold.  (Minimum is 0.)  */
  91 #define USHRT_MAX       65535
  92
  93 /* Minimum and maximum values a `signed int' can hold.  */
  94 #define INT_MIN (- INT_MAX - 1)
  95 #define INT_MAX 2147483647
  96
  97 /* Maximum value an `unsigned int' can hold.  (Minimum is 0.)  */
  98 #ifdef  __STDC__
  99 #define UINT_MAX        4294967295U
 100 #else
 101 #define UINT_MAX        4294967295
 102 #endif
 103
 104 /* Minimum and maximum values a `signed long int' can hold.  */
 105 #define LONG_MIN        INT_MIN
 106 #define LONG_MAX        INT_MAX
 107
 108 /* Maximum value an `unsigned long int' can hold.  (Minimum is 0.)  */
 109 #define ULONG_MAX       UINT_MAX
 110
 111 #endif  /* limits.h  */
 112 #endif  /* GCC 2.  */