xref: /illumos-gate/usr/src/lib/libc/port/locale/towlower.c (revision a6bde1a23b60f140c7ed78df979c2e22b1ed9b2c)
1 /*
2  * Copyright 2013 Garrett D'Amore <garrett@damore.org>
3  * Copyright 2010 Nexenta Systems, Inc.  All rights reserved.
4  * Copyright (c) 1989, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  * (c) UNIX System Laboratories, Inc.
7  * All or some portions of this file are derived from material licensed
8  * to the University of California by American Telephone and Telegraph
9  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10  * the permission of UNIX System Laboratories, Inc.
11  *
12  * This code is derived from software contributed to Berkeley by
13  * Paul Borman at Krystal Technologies.
14  *
15  * Redistribution and use in source and binary forms, with or without
16  * modification, are permitted provided that the following conditions
17  * are met:
18  * 1. Redistributions of source code must retain the above copyright
19  *    notice, this list of conditions and the following disclaimer.
20  * 2. Redistributions in binary form must reproduce the above copyright
21  *    notice, this list of conditions and the following disclaimer in the
22  *    documentation and/or other materials provided with the distribution.
23  * 4. Neither the name of the University nor the names of its contributors
24  *    may be used to endorse or promote products derived from this software
25  *    without specific prior written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37  * SUCH DAMAGE.
38  */
39 
40 #include "lint.h"
41 #include <wctype.h>
42 #include <stdio.h>
43 #include "localeimpl.h"
44 #include "lctype.h"
45 #include "runetype.h"
46 
47 static wint_t
48 change_case_ext(locale_t loc, wint_t c, int lower)
49 {
50 	const _RuneLocale *rl;
51 	const _RuneRange *rr;
52 	const _RuneEntry *base, *re;
53 	size_t lim;
54 
55 	if (c < 0 || c == EOF)
56 		return (c);
57 
58 	rl = loc->runelocale;
59 	rr = lower ? &rl->__maplower_ext : &rl->__mapupper_ext;
60 	/* Binary search -- see bsearch.c for explanation. */
61 	base = rr->__ranges;
62 	for (lim = rr->__nranges; lim != 0; lim >>= 1) {
63 		re = base + (lim >> 1);
64 		if (re->__min <= c && c <= re->__max) {
65 			return (re->__map + c - re->__min);
66 		} else if (c > re->__max) {
67 			base = re + 1;
68 			lim--;
69 		}
70 	}
71 
72 	return (c);
73 }
74 
75 wint_t
76 towlower_l(wint_t wc, locale_t loc)
77 {
78 	return (iswascii(wc) ? __trans_lower[wc] :
79 	    (wc < 0 || wc >= _CACHED_RUNES) ?
80 	    change_case_ext(loc, wc, 1) :
81 	    loc->runelocale->__maplower[wc]);
82 }
83 
84 #undef towlower
85 wint_t
86 towlower(wint_t wc)
87 {
88 	return (iswascii(wc) ? __trans_lower[wc] :
89 	    (wc < 0 || wc >= _CACHED_RUNES) ?
90 	    change_case_ext(uselocale(NULL), wc, 1) :
91 	    uselocale(NULL)->runelocale->__maplower[wc]);
92 }
93 
94 wint_t
95 towupper_l(wint_t wc, locale_t loc)
96 {
97 	return (iswascii(wc) ? __trans_upper[wc] :
98 	    (wc < 0 || wc >= _CACHED_RUNES) ?
99 	    change_case_ext(loc, wc, 0) :
100 	    loc->runelocale->__mapupper[wc]);
101 }
102 
103 #undef towupper
104 wint_t
105 towupper(wint_t wc)
106 {
107 	return (iswascii(wc) ? __trans_upper[wc] :
108 	    (wc < 0 || wc >= _CACHED_RUNES) ?
109 	    change_case_ext(uselocale(NULL), wc, 0) :
110 	    uselocale(NULL)->runelocale->__mapupper[wc]);
111 }
112