xref: /illumos-gate/usr/src/lib/libc/port/locale/wcwidth.c (revision 694c35faa87b858ecdadfe4fc592615f4eefbb07)
1 /*
2  * Copyright (c) 1989, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  * (c) UNIX System Laboratories, Inc.
5  * All or some portions of this file are derived from material licensed
6  * to the University of California by American Telephone and Telegraph
7  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8  * the permission of UNIX System Laboratories, Inc.
9  *
10  * This code is derived from software contributed to Berkeley by
11  * Paul Borman at Krystal Technologies.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  * 4. Neither the name of the University nor the names of its contributors
22  *    may be used to endorse or promote products derived from this software
23  *    without specific prior written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35  * SUCH DAMAGE.
36  */
37 
38 /*
39  * Copyright 2010 Nexenta Systems, Inc.  All rights reserved.
40  * Use is subject to license terms.
41  */
42 
43 #include "lint.h"
44 #include <wchar.h>
45 #include "_ctype.h"
46 #include "runetype.h"
47 
48 #undef wcwidth
49 
50 int
51 wcwidth(wchar_t wc)
52 {
53 	unsigned int x;
54 
55 	if (wc == 0)
56 		return (0);
57 
58 	x = ((wc < 0 || wc >= _CACHED_RUNES) ? ___runetype(wc) :
59 	    _CurrentRuneLocale->__runetype[wc]) & (_CTYPE_SWM|_CTYPE_R);
60 
61 	if ((x & _CTYPE_SWM) != 0)
62 		return ((x & _CTYPE_SWM) >> _CTYPE_SWS);
63 	return ((x & _CTYPE_R) != 0 ? 1 : -1);
64 }
65 
66 #pragma weak _scrwidth = scrwidth
67 
68 /*
69  * This is a Solaris extension.  It never returns a negative width, even for
70  * non-printable characters.  It is used internally by the printf
71  * implementation for %ws.
72  */
73 int
74 scrwidth(wchar_t wc)
75 {
76 	int	v = wcwidth(wc);
77 	return (v > 0 ? v : 0);
78 }
79