mbscspn.c

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/***
*mbscspn.c - Find first string char in charset (MBCS)
*
*       Copyright (c) 1985-1997, Microsoft Corporation.  All rights reserved.
*
*Purpose:
*       Find first string char in charset (MBCS)
*
*******************************************************************************/

#ifdef _MBCS

#include <mtdll.h>
#include <cruntime.h>
#include <string.h>
#include <mbdata.h>
#include <mbctype.h>
#include <mbstring.h>
#include <stddef.h>


/***
*ifndef _RETURN_PTR
* _mbscspn - Find first string char in charset (MBCS)
*else
* _mbspbrk - Find first string char in charset, pointer return (MBCS)
*endif
*
*Purpose:
*       Returns maximum leading segment of string
*       which consists solely of characters NOT from charset.
*       Handles MBCS chars correctly.
*
*Entry:
*       char *string = string to search in
*       char *charset = set of characters to scan over
*
*Exit:
*
*ifndef _RETURN_PTR
*       Returns the index of the first char in string
*       that is in the set of characters specified by control.
*
*       Returns 0, if string begins with a character in charset.
*else
*       Returns pointer to first character in charset.
*
*       Returns NULL if string consists entirely of characters
*       not from charset.
*endif
*
*Exceptions:
*
*******************************************************************************/

#ifndef _RETURN_PTR

size_t __cdecl _mbscspn( string, charset )
const unsigned char *string;
const unsigned char *charset;

#else  /* _RETURN_PTR */

unsigned char * __cdecl _mbspbrk( string, charset )
const unsigned char *string;
const unsigned char  *charset;

#endif  /* _RETURN_PTR */

{
        unsigned char *p, *q;

        if ( _ISNOTMBCP )
#ifndef _RETURN_PTR
            return strcspn(string, charset);
#else  /* _RETURN_PTR */
            return strpbrk(string, charset);
#endif  /* _RETURN_PTR */

        _mlock(_MB_CP_LOCK);

        /* loop through the string to be inspected */
        for (q = (char *)string; *q ; q++) {

                /* loop through the charset */
                for (p = (char *)charset; *p ; p++) {

                        if (_ISLEADBYTE(*p)) {
                                if (((*p == *q) && (p[1] == q[1])) || p[1] == '\0')
                                        break;
                                p++;
                        }

                        else
                                if (*p == *q)
                                        break;
                }

                if (*p != '\0')         /* end of charset? */
                        break;          /* no, match on this char */

                if (_ISLEADBYTE(*q))
                        if (*++q == '\0')
                                break;
        }

        _munlock(_MB_CP_LOCK);

#ifndef _RETURN_PTR
        return((size_t) (q - string));          /* index */
#else  /* _RETURN_PTR */
        return((*q) ? q : NULL);        /* pointer */
#endif  /* _RETURN_PTR */

}

#endif  /* _MBCS */