tolower.c revision 331722 
1/*-
2 * Copyright (c) 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Paul Borman at Krystal Technologies.
7 *
8 * Copyright (c) 2011 The FreeBSD Foundation
9 * All rights reserved.
10 * Portions of this software were developed by David Chisnall
11 * under sponsorship from the FreeBSD Foundation.
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#include <sys/cdefs.h>
39__FBSDID("$FreeBSD: stable/11/lib/libc/locale/tolower.c 331722 2018-03-29 02:50:57Z eadler $");
40
41#include <ctype.h>
42#include <stdio.h>
43#include <runetype.h>
44#include <wchar.h>
45#include "mblocal.h"
46
47__ct_rune_t
48___tolower_l(__ct_rune_t c, locale_t l)
49{
50	size_t lim;
51	FIX_LOCALE(l);
52	_RuneRange *rr = &XLOCALE_CTYPE(l)->runes->__maplower_ext;
53	_RuneEntry *base, *re;
54
55	if (c < 0 || c == EOF)
56		return(c);
57
58	/* Binary search -- see bsearch.c for explanation. */
59	base = rr->__ranges;
60	for (lim = rr->__nranges; lim != 0; lim >>= 1) {
61		re = base + (lim >> 1);
62		if (re->__min <= c && c <= re->__max)
63			return (re->__map + c - re->__min);
64		else if (c > re->__max) {
65			base = re + 1;
66			lim--;
67		}
68	}
69
70	return(c);
71}
72__ct_rune_t
73___tolower(__ct_rune_t c)
74{
75	return ___tolower_l(c, __get_locale());
76}
77