port/locale/wcwidth.c

	wcwidth.c revision 4297a3b0d0a35d80f86fff155e288e885a100e6d
/*
 * Copyright (c) 1989, 1993
 *  The Regents of the University of California.  All rights reserved.
 * (c) UNIX System Laboratories, Inc.
 * All or some portions of this file are derived from material licensed
 * to the University of California by American Telephone and Telegraph
 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
 * the permission of UNIX System Laboratories, Inc.
 *
 * This code is derived from software contributed to Berkeley by
 * Paul Borman at Krystal Technologies.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/*
 * Copyright 2010 Nexenta Systems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#include "lint.h"
#include <wchar.h>
#include "_ctype.h"
#include "runetype.h"

#undef wcwidth

int
wcwidth(wchar_t wc)
{
    unsigned int x;

    if (wc == 0)
        return (0);

    x = ((wc < 0 || wc >= _CACHED_RUNES) ? ___runetype(wc) :
        _CurrentRuneLocale->__runetype[wc]) & (_CTYPE_SWM|_CTYPE_R);

    if ((x & _CTYPE_SWM) != 0)
        return ((x & _CTYPE_SWM) >> _CTYPE_SWS);
    return ((x & _CTYPE_R) != 0 ? 1 : -1);
}

#pragma weak _scrwidth = scrwidth

/*
 * This is a Solaris extension.  I don't really understand why a different
 * function was needed.  Anecdotally, it appears that perhaps some versions
 * of the Sun wcwidth didn't handle illegal encodings well, and scrwidth
 * seems to have been better.  Its not an issue for our implementation.
 */
int
scrwidth(wchar_t wc)
{
    return (wcwidth(wc));
}