usr.bin/elvis/ctype.c

/* ctype.c */

/* This file contains the tables and initialization function for elvis'
 * version of <ctype.h>.  It should be portable.
 */

#include "config.h"
#include "ctype.h"

void _ct_init P_((uchar *));

uchar   _ct_toupper[256];
uchar   _ct_tolower[256];
uchar   _ct_ctypes[256];

/* This function initializes the tables used by the ctype macros.  It should
 * be called at the start of the program.  It can be called again anytime you
 * wish to change the non-standard "flipcase" list.  The "flipcase" list is
 * a string of characters which are taken to be lowercase/uppercase pairs.
 * If you don't want to use any special flipcase characters, then pass an
 * empty string.
 */
void _ct_init(flipcase)
        uchar   *flipcase;      /* list of non-standard lower/upper letter pairs */
{
        int     i;
        uchar   *scan;

        /* reset all of the tables */
        for (i = 0; i < 256; i++)
        {
                _ct_toupper[i] = _ct_tolower[i] = i;
                _ct_ctypes[i] = 0;
        }

        /* add the digits */
        for (scan = (uchar *)"0123456789"; *scan; scan++)
        {
                _ct_ctypes[*scan] |= _CT_DIGIT | _CT_ALNUM;
        }

        /* add the whitespace */
        for (scan = (uchar *)" \t\n\r\f"; *scan; scan++)
        {
                _ct_ctypes[*scan] |= _CT_SPACE;
        }

        /* add the standard ASCII letters */
        for (scan = (uchar *)"aAbBcCdDeEfFgGhHiIjJkKlLmMnNoOpPqQrRsStTuUvVwWxXyYzZ"; *scan; scan += 2)
        {
                _ct_ctypes[scan[0]] |= _CT_LOWER | _CT_ALNUM;
                _ct_ctypes[scan[1]] |= _CT_UPPER | _CT_ALNUM;
                _ct_toupper[scan[0]] = scan[1];
                _ct_tolower[scan[1]] = scan[0];
        }

        /* add the flipcase letters */
        for (scan = flipcase; scan[0] && scan[1]; scan += 2)
        {
                _ct_ctypes[scan[0]] |= _CT_LOWER | _CT_ALNUM;
                _ct_ctypes[scan[1]] |= _CT_UPPER | _CT_ALNUM;
                _ct_toupper[scan[0]] = scan[1];
                _ct_tolower[scan[1]] = scan[0];
        }

        /* include '_' in the isalnum() list */
        _ct_ctypes[UCHAR('_')] |= _CT_ALNUM;

        /* !!! find the control characters in an ASCII-dependent way */
        for (i = 0; i < ' '; i++)
        {
                _ct_ctypes[i] |= _CT_CNTRL;
        }
        _ct_ctypes[127] |= _CT_CNTRL;
        _ct_ctypes[255] |= _CT_CNTRL;
}