kolibrios/programs/develop/open watcom/trunk/clib/mbyte/mbtowc.c
Sergey Semyonov (Serge) 275695e8c3 update clib
git-svn-id: svn://kolibrios.org@701 a494cfbc-eb01-0410-851d-a64ba20cac60
2008-01-23 19:23:33 +00:00

71 lines
2.7 KiB
C

/****************************************************************************
*
* Open Watcom Project
*
* Portions Copyright (c) 1983-2002 Sybase, Inc. All Rights Reserved.
*
* ========================================================================
*
* This file contains Original Code and/or Modifications of Original
* Code as defined in and that are subject to the Sybase Open Watcom
* Public License version 1.0 (the 'License'). You may not use this file
* except in compliance with the License. BY USING THIS FILE YOU AGREE TO
* ALL TERMS AND CONDITIONS OF THE LICENSE. A copy of the License is
* provided with the Original Code and Modifications, and is also
* available at www.sybase.com/developer/opensource.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND SYBASE AND ALL CONTRIBUTORS HEREBY DISCLAIM
* ALL SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR
* NON-INFRINGEMENT. Please see the License for the specific language
* governing rights and limitations under the License.
*
* ========================================================================
*
* Description: WHEN YOU FIGURE OUT WHAT THIS FILE DOES, PLEASE
* DESCRIBE IT HERE!
*
****************************************************************************/
#include "variety.h"
#include <mbstring.h>
#include "farfunc.h"
/****
***** Convert a multibyte character to a wide character.
****/
_WCRTLINK int _NEARFAR(mbtowc,_fmbtowc)( wchar_t _FFAR *pwc, const char _FFAR *ch, size_t n )
{
/*** Catch special cases ***/
if( ch == NULL ) return( 0 );
if( n == 0 ) return( -1 );
if( *ch == '\0' ) {
if( pwc != NULL ) *pwc = L'\0';
return( 0 );
}
if( _ismbblead( ch[0] ) && ch[1] == '\0' ) return( -1 ); /* invalid */
/*** Convert the character ***/
if( _ismbblead(*ch) && n>=2 ) { /* lead byte present? */
if( pwc != NULL ) {
*pwc = (((wchar_t)ch[0])<<8) | /* convert to lead:trail */
(wchar_t)ch[1];
}
return( 2 ); /* return char size */
} else if( !_ismbblead(*ch) ) {
if( pwc != NULL ) {
*pwc = (wchar_t)ch[0]; /* convert to 00:byte */
}
return( 1 ); /* return char size */
} else {
return( -1 ); /* n==1, but char 2 bytes */
}
}