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kit
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limits.h (1950B)

      1 /* limits.h -- C11 7.10 -- Sizes of integer types
      2  *
      3  * kit assumes a target where:
      4  *   - CHAR_BIT == 8
      5  *   - short == 16 bits
      6  *   - int   == 32 bits
      7  *   - long long == 64 bits
      8  *   - two's complement representation
      9  * These hold on every modern C11 target we care about. The signedness of
     10  * plain `char` and the width of `long` genuinely differ across targets and
     11  * are still derived from compiler-predefined macros.
     12  */
     13 #ifndef KIT_LIMITS_H
     14 #define KIT_LIMITS_H
     15 
     16 #define CHAR_BIT 8
     17 #define BOOL_WIDTH 1
     18 #define CHAR_WIDTH 8
     19 #define SCHAR_WIDTH 8
     20 #define UCHAR_WIDTH 8
     21 #define SHRT_WIDTH 16
     22 #define USHRT_WIDTH 16
     23 #define INT_WIDTH 32
     24 #define UINT_WIDTH 32
     25 #define LONG_WIDTH (__SIZEOF_LONG__ * CHAR_BIT)
     26 #define ULONG_WIDTH (__SIZEOF_LONG__ * CHAR_BIT)
     27 #define LLONG_WIDTH 64
     28 #define ULLONG_WIDTH 64
     29 #define MB_LEN_MAX 1 /* freestanding has no locale; smallest legal value */
     30 
     31 /* signed / unsigned char */
     32 #define SCHAR_MAX 127
     33 #define SCHAR_MIN (-128)
     34 #define UCHAR_MAX 255
     35 
     36 /* plain char -- signedness is implementation-defined and set by the
     37    compiler/ABI; a header cannot change it. We report what the compiler
     38    chose. -funsigned-char / -fsigned-char flip __CHAR_UNSIGNED__. */
     39 #ifdef __CHAR_UNSIGNED__
     40 #define CHAR_MIN 0
     41 #define CHAR_MAX 255
     42 #else
     43 #define CHAR_MIN (-128)
     44 #define CHAR_MAX 127
     45 #endif
     46 
     47 /* short / unsigned short */
     48 #define SHRT_MAX 32767
     49 #define SHRT_MIN (-32768)
     50 #define USHRT_MAX 65535
     51 
     52 /* int / unsigned int */
     53 #define INT_MAX 2147483647
     54 #define INT_MIN (-INT_MAX - 1)
     55 #define UINT_MAX 4294967295U
     56 
     57 /* long / unsigned long -- LP64 (Unix 64-bit) makes long 64-bit, while
     58    LLP64 (Windows 64-bit) and ILP32 keep it 32-bit. Genuinely varying. */
     59 #define LONG_MAX __LONG_MAX__
     60 #define LONG_MIN (-LONG_MAX - 1L)
     61 #define ULONG_MAX (LONG_MAX * 2UL + 1UL)
     62 
     63 /* long long / unsigned long long */
     64 #define LLONG_MAX 9223372036854775807LL
     65 #define LLONG_MIN (-LLONG_MAX - 1LL)
     66 #define ULLONG_MAX 18446744073709551615ULL
     67 
     68 #endif