lctype.h

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/*
** $Id: lctype.h $
** 'ctype' functions for Lua
** See Copyright Notice in lua.h
*/

#ifndef lctype_h
#define lctype_h
 
#include "lua.h"
 
 
/*
** WARNING: the functions defined here do not necessarily correspond
** to the similar functions in the standard C ctype.h. They are
** optimized for the specific needs of Lua.
*/
 
#if !defined(LUA_USE_CTYPE)
 
#if 'A' == 65 && '0' == 48
/* ASCII case: can use its own tables; faster and fixed */
#define LUA_USE_CTYPE   0
#else
/* must use standard C ctype */
#define LUA_USE_CTYPE   1
#endif
 
#endif
 
 
#if !LUA_USE_CTYPE  /* { */
 
#include <limits.h>
 
#include "llimits.h"
 
 
#define ALPHABIT    0
#define DIGITBIT    1
#define PRINTBIT    2
#define SPACEBIT    3
#define XDIGITBIT   4
 
 
#define MASK(B)     (1 << (B))
 
 
/*
** add 1 to char to allow index -1 (EOZ)
*/
#define testprop(c,p)   (luai_ctype_[(c)+1] & (p))
 
/*
** 'lalpha' (Lua alphabetic) and 'lalnum' (Lua alphanumeric) both include '_'
*/
#define lislalpha(c)    testprop(c, MASK(ALPHABIT))
#define lislalnum(c)    testprop(c, (MASK(ALPHABIT) | MASK(DIGITBIT)))
#define lisdigit(c) testprop(c, MASK(DIGITBIT))
#define lisspace(c) testprop(c, MASK(SPACEBIT))
#define lisprint(c) testprop(c, MASK(PRINTBIT))
#define lisxdigit(c)    testprop(c, MASK(XDIGITBIT))
 
 
/*
** In ASCII, this 'ltolower' is correct for alphabetic characters and
** for '.'. That is enough for Lua needs. ('check_exp' ensures that
** the character either is an upper-case letter or is unchanged by
** the transformation, which holds for lower-case letters and '.'.)
*/
#define ltolower(c)  \
  check_exp(('A' <= (c) && (c) <= 'Z') || (c) == ((c) | ('A' ^ 'a')),  \
            (c) | ('A' ^ 'a'))
 
 
/* one entry for each character and for -1 (EOZ) */
LUAI_DDEC(const lu_byte luai_ctype_[UCHAR_MAX + 2];)
 
 
#else           /* }{ */
 
/*
** use standard C ctypes
*/
 
#include <ctype.h>
 
 
#define lislalpha(c)    (isalpha(c) || (c) == '_')
#define lislalnum(c)    (isalnum(c) || (c) == '_')
#define lisdigit(c) (isdigit(c))
#define lisspace(c) (isspace(c))
#define lisprint(c) (isprint(c))
#define lisxdigit(c)    (isxdigit(c))
 
#define ltolower(c) (tolower(c))
 
#endif          /* } */
 
#endif