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Reactos
1/***
2*mbsnbcnt.c - Returns byte count of MBCS string
3*
4* Copyright (c) Microsoft Corporation. All rights reserved.
5*
6*Purpose:
7* Returns byte count of MBCS string
8*
9*******************************************************************************/
10#ifndef _MBCS
11 #error This file should only be compiled with _MBCS defined
12#endif
13
14#include <corecrt_internal_mbstring.h>
15#include <locale.h>
16
17/***
18* _mbsnbcnt - Returns byte count of MBCS string
19*
20*Purpose:
21* Returns the number of bytes between the start of the supplied
22* string and the char count supplied. That is, this routine
23* indicates how many bytes are in the first "ccnt" characters
24* of the string.
25*
26*Entry:
27* unsigned char *string = pointer to string
28* unsigned int ccnt = number of characters to scan
29*
30*Exit:
31* Returns number of bytes between string and ccnt.
32*
33* If the end of the string is encountered before ccnt chars were
34* scanned, then the length of the string in bytes is returned.
35*
36*Exceptions:
37* Input parameters are validated. Refer to the validation section of the function.
38*
39*******************************************************************************/
40
41extern "C" size_t __cdecl _mbsnbcnt_l(
42 const unsigned char *string,
43 size_t ccnt,
44 _locale_t plocinfo
45 )
46{
47 unsigned char *p;
48 _LocaleUpdate _loc_update(plocinfo);
49
50 /* validation section */
51 _VALIDATE_RETURN(string != nullptr || ccnt == 0, EINVAL, 0);
52
53 for (p = (unsigned char *)string; (ccnt-- && *p); p++) {
54 if ( _ismbblead_l(*p, _loc_update.GetLocaleT()) ) {
55 if (*++p == '\0') {
56 --p;
57 break;
58 }
59 }
60 }
61
62 return ((size_t) ((char *)p - (char *)string));
63}
64
65extern "C" size_t (__cdecl _mbsnbcnt)(
66 const unsigned char *string,
67 size_t ccnt
68 )
69{
70 return _mbsnbcnt_l(string, ccnt, nullptr);
71}