windows-nt/Source/XPSP1/NT/base/crts/crtw32/convert/wcstombs.c

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2020-09-26 03:20:57 -05:00
/***
*wcstombs.c - Convert wide char string to multibyte char string.
*
* Copyright (c) 1990-2001, Microsoft Corporation. All rights reserved.
*
*Purpose:
* Convert a wide char string into the equivalent multibyte char string.
*
*Revision History:
* 08-24-90 KRS Module created.
* 01-14-91 KRS Added _WINSTATIC for Windows DLL. Fix wctomb() call.
* 03-18-91 KRS Fix check for NUL.
* 03-20-91 KRS Ported from 16-bit tree.
* 10-16-91 ETC Locale support under _INTL switch.
* 12-09-91 ETC Updated nlsapi; added multithread.
* 08-20-92 KRS Activated NLSAPI support.
* 08-22-92 SRW Allow INTL definition to be conditional for building ntcrt.lib
* 09-02-92 SRW Get _INTL definition via ..\crt32.def
* 01-06-93 CFW Added (count < n) to outer loop - avoid bad wctomb calls
* 01-07-93 KRS Major code cleanup. Fix error return, comments.
* 04-06-93 SKS Replace _CRTAPI* with _cdecl
* 05-03-93 CFW Return pointer == NULL, return size, plus massive cleanup.
* 06-01-93 CFW Minor optimization and beautify.
* 06-02-93 SRW ignore _INTL if _NTSUBSET_ defined.
* 09-15-93 CFW Use ANSI conformant "__" names.
* 09-28-93 GJF Merged NT SDK and Cuda versions.
* 01-14-94 SRW if _NTSUBSET_ defined call Rtl functions
* 02-07-94 CFW POSIXify.
* 08-03-94 CFW Optimize for SBCS.
* 09-06-94 CFW Remove _INTL switch.
* 11-22-94 CFW WideCharToMultiByte will compare past NULL.
* 01-07-95 CFW Mac merge cleanup.
* 02-06-95 CFW assert -> _ASSERTE.
* 03-13-95 CFW Fix wcsncnt counting.
* 04-19-95 CFW Rearrange & fix non-Win32 version.
* 09-26-95 GJF New locking macro, and scheme, for functions which
* reference the locale.
* 12-07-95 SKS Fix misspelling of _NTSUBSET_ (final _ was missing)
* 04-01-96 BWT POSIX work.
* 06-25-96 GJF Removed DLL_FOR_WIN32S. Replaced defined(_WIN32) with
* !defined(_MAC). Polished the format a bit.
* 02-27-98 RKP Added 64 bit support.
* 06-23-98 GJF Revised multithread support based on threadlocinfo
* struct.
* 08-27-98 GJF Introduced __wcstombs_mt.
* 12-15-98 GJF Changes for 64-bit size_t.
* 04-28-99 GJF Changed dwFlags arg value to 0 in WideCharToMultiByte
* calls to avoid problems with codepage 1258 on NT 5.0.
* 05-17-99 PML Remove all Macintosh support.
*
*******************************************************************************/
#if defined(_NTSUBSET_) || defined(_POSIX_)
#include <nt.h>
#include <ntrtl.h>
#include <nturtl.h>
#endif
#include <cruntime.h>
#include <stdlib.h>
#include <limits.h>
#include <internal.h>
#include <mtdll.h>
#include <dbgint.h>
#include <errno.h>
#include <locale.h>
#include <setlocal.h>
/***
*int __cdecl wcsncnt - count wide characters in a string, up to n.
*
*Purpose:
* Internal local support function. Counts characters in string including NULL.
* If NULL not found in n chars, then return n.
*
*Entry:
* const wchar_t *string - start of string
* size_t n - character count
*
*Exit:
* returns number of wide characters from start of string to
* NULL (inclusive), up to n.
*
*Exceptions:
*
*******************************************************************************/
static size_t __cdecl wcsncnt (
const wchar_t *string,
size_t cnt
)
{
size_t n = cnt+1;
wchar_t *cp = (wchar_t *)string;
while (--n && *cp)
cp++;
if (n && !*cp)
return cp - string + 1;
return cnt;
}
/***
*size_t wcstombs() - Convert wide char string to multibyte char string.
*
*Purpose:
* Convert a wide char string into the equivalent multibyte char string,
* according to the LC_CTYPE category of the current locale.
* [ANSI].
*
* NOTE: Currently, the C libraries support the "C" locale only.
* Non-C locale support now available under _INTL switch.
*Entry:
* char *s = pointer to destination multibyte char string
* const wchar_t *pwc = pointer to source wide character string
* size_t n = maximum number of bytes to store in s
*
*Exit:
* If s != NULL, returns (size_t)-1 (if a wchar cannot be converted)
* Otherwise: Number of bytes modified (<=n), not including
* the terminating NUL, if any.
*
*Exceptions:
* Returns (size_t)-1 if s is NULL or invalid mb character encountered.
*
*******************************************************************************/
size_t __cdecl wcstombs (
char * s,
const wchar_t * pwcs,
size_t n
)
{
#ifdef _MT
pthreadlocinfo ptloci = _getptd()->ptlocinfo;
if ( ptloci != __ptlocinfo )
ptloci = __updatetlocinfo();
return __wcstombs_mt(ptloci, s, pwcs, n);
}
size_t __cdecl __wcstombs_mt (
pthreadlocinfo ptloci,
char * s,
const wchar_t * pwcs,
size_t n
)
{
#endif
size_t count = 0;
int i, retval;
char buffer[MB_LEN_MAX];
BOOL defused = 0;
if (s && n == 0)
/* dest string exists, but 0 bytes converted */
return (size_t) 0;
_ASSERTE(pwcs != NULL);
#ifdef _WIN64
/* n must fit into an int for WideCharToMultiByte */
if ( n > INT_MAX )
return (size_t)-1;
#endif
#if !defined( _NTSUBSET_ ) && !defined(_POSIX_)
/* if destination string exists, fill it in */
if (s)
{
#ifdef _MT
if ( ptloci->lc_handle[LC_CTYPE] == _CLOCALEHANDLE )
#else
if ( __lc_handle[LC_CTYPE] == _CLOCALEHANDLE )
#endif
{
/* C locale: easy and fast */
while(count < n)
{
if (*pwcs > 255) /* validate high byte */
{
errno = EILSEQ;
return (size_t)-1; /* error */
}
s[count] = (char) *pwcs;
if (*pwcs++ == L'\0')
return count;
count++;
}
return count;
} else {
if (1 == MB_CUR_MAX)
{
/* If SBCS, one wchar_t maps to one char */
/* WideCharToMultiByte will compare past NULL - reset n */
if (n > 0)
n = wcsncnt(pwcs, n);
#ifdef _MT
if ( ((count = WideCharToMultiByte( ptloci->lc_codepage,
#else
if ( ((count = WideCharToMultiByte( __lc_codepage,
#endif
0,
pwcs,
(int)n,
s,
(int)n,
NULL,
&defused )) != 0) &&
(!defused) )
{
if (*(s + count - 1) == '\0')
count--; /* don't count NUL */
return count;
}
errno = EILSEQ;
return (size_t)-1;
}
else {
/* If MBCS, wchar_t to char mapping unknown */
/* Assume that usually the buffer is large enough */
#ifdef _MT
if ( ((count = WideCharToMultiByte( ptloci->lc_codepage,
#else
if ( ((count = WideCharToMultiByte( __lc_codepage,
#endif
0,
pwcs,
-1,
s,
(int)n,
NULL,
&defused )) != 0) &&
(!defused) )
{
return count - 1; /* don't count NUL */
}
if (defused || GetLastError() != ERROR_INSUFFICIENT_BUFFER)
{
errno = EILSEQ;
return (size_t)-1;
}
/* buffer not large enough, must do char by char */
while (count < n)
{
#ifdef _MT
if ( ((retval = WideCharToMultiByte( ptloci->lc_codepage,
#else
if ( ((retval = WideCharToMultiByte( __lc_codepage,
#endif
0,
pwcs,
1,
buffer,
MB_CUR_MAX,
NULL,
&defused )) == 0)
|| defused )
{
errno = EILSEQ;
return (size_t)-1;
}
if (count + retval > n)
return count;
for (i = 0; i < retval; i++, count++) /* store character */
if((s[count] = buffer[i])=='\0')
return count;
pwcs++;
}
return count;
}
}
}
else { /* s == NULL, get size only, pwcs must be NUL-terminated */
#ifdef _MT
if ( ptloci->lc_handle[LC_CTYPE] == _CLOCALEHANDLE )
#else
if ( __lc_handle[LC_CTYPE] == _CLOCALEHANDLE )
#endif
return wcslen(pwcs);
else {
#ifdef _MT
if ( ((count = WideCharToMultiByte( ptloci->lc_codepage,
#else
if ( ((count = WideCharToMultiByte( __lc_codepage,
#endif
0,
pwcs,
-1,
NULL,
0,
NULL,
&defused )) == 0) ||
(defused) )
{
errno = EILSEQ;
return (size_t)-1;
}
return count - 1;
}
}
#else /* _NTSUBSET_/_POSIX_ */
/* if destination string exists, fill it in */
if (s)
{
NTSTATUS Status;
Status = RtlUnicodeToMultiByteN( s,
(ULONG) n,
(PULONG)&count,
(wchar_t *)pwcs,
(wcslen(pwcs) + 1) *
sizeof(WCHAR) );
if (NT_SUCCESS(Status))
{
return count - 1; /* don't count NUL */
} else {
errno = EILSEQ;
count = (size_t)-1;
}
} else { /* s == NULL, get size only, pwcs must be NUL-terminated */
NTSTATUS Status;
Status = RtlUnicodeToMultiByteSize( (PULONG)&count,
(wchar_t *)pwcs,
(wcslen(pwcs) + 1) *
sizeof(WCHAR) );
if (NT_SUCCESS(Status))
{
return count - 1; /* don't count NUL */
} else {
errno = EILSEQ;
count = (size_t)-1;
}
}
return count;
#endif /* _NTSUBSET_/_POSIX_ */
}