xref: /freebsd/lib/libc/string/wcscoll.c (revision 3c87aa1d3dc1d8dad3efad322852a8e1e76dee55)
1fd4f1dd9STim J. Robbins /*-
2fd4f1dd9STim J. Robbins  * Copyright (c) 2002 Tim J. Robbins
3fd4f1dd9STim J. Robbins  * All rights reserved.
4fd4f1dd9STim J. Robbins  *
5*3c87aa1dSDavid Chisnall  * Copyright (c) 2011 The FreeBSD Foundation
6*3c87aa1dSDavid Chisnall  * All rights reserved.
7*3c87aa1dSDavid Chisnall  * Portions of this software were developed by David Chisnall
8*3c87aa1dSDavid Chisnall  * under sponsorship from the FreeBSD Foundation.
9*3c87aa1dSDavid Chisnall  *
10fd4f1dd9STim J. Robbins  * Redistribution and use in source and binary forms, with or without
11fd4f1dd9STim J. Robbins  * modification, are permitted provided that the following conditions
12fd4f1dd9STim J. Robbins  * are met:
13fd4f1dd9STim J. Robbins  * 1. Redistributions of source code must retain the above copyright
14fd4f1dd9STim J. Robbins  *    notice, this list of conditions and the following disclaimer.
15fd4f1dd9STim J. Robbins  * 2. Redistributions in binary form must reproduce the above copyright
16fd4f1dd9STim J. Robbins  *    notice, this list of conditions and the following disclaimer in the
17fd4f1dd9STim J. Robbins  *    documentation and/or other materials provided with the distribution.
18fd4f1dd9STim J. Robbins  *
19fd4f1dd9STim J. Robbins  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20fd4f1dd9STim J. Robbins  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21fd4f1dd9STim J. Robbins  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22fd4f1dd9STim J. Robbins  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23fd4f1dd9STim J. Robbins  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24fd4f1dd9STim J. Robbins  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25fd4f1dd9STim J. Robbins  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26fd4f1dd9STim J. Robbins  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27fd4f1dd9STim J. Robbins  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28fd4f1dd9STim J. Robbins  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29fd4f1dd9STim J. Robbins  * SUCH DAMAGE.
30fd4f1dd9STim J. Robbins  */
31fd4f1dd9STim J. Robbins 
32fd4f1dd9STim J. Robbins #include <sys/cdefs.h>
33fd4f1dd9STim J. Robbins __FBSDID("$FreeBSD$");
34fd4f1dd9STim J. Robbins 
35fd4f1dd9STim J. Robbins #include <errno.h>
36fd4f1dd9STim J. Robbins #include <stdlib.h>
37fd4f1dd9STim J. Robbins #include <string.h>
38fd4f1dd9STim J. Robbins #include <wchar.h>
39fd4f1dd9STim J. Robbins #include "collate.h"
40fd4f1dd9STim J. Robbins 
41fd4f1dd9STim J. Robbins static char *__mbsdup(const wchar_t *);
42fd4f1dd9STim J. Robbins 
43fd4f1dd9STim J. Robbins /*
44fd4f1dd9STim J. Robbins  * Placeholder implementation of wcscoll(). Attempts to use the single-byte
45fd4f1dd9STim J. Robbins  * collation ordering where possible, and falls back on wcscmp() in locales
46fd4f1dd9STim J. Robbins  * with extended character sets.
47fd4f1dd9STim J. Robbins  */
48fd4f1dd9STim J. Robbins int
49*3c87aa1dSDavid Chisnall wcscoll_l(const wchar_t *ws1, const wchar_t *ws2, locale_t locale)
50fd4f1dd9STim J. Robbins {
51fd4f1dd9STim J. Robbins 	char *mbs1, *mbs2;
52fd4f1dd9STim J. Robbins 	int diff, sverrno;
53*3c87aa1dSDavid Chisnall 	FIX_LOCALE(locale);
54*3c87aa1dSDavid Chisnall 	struct xlocale_collate *table =
55*3c87aa1dSDavid Chisnall 		(struct xlocale_collate*)locale->components[XLC_COLLATE];
56fd4f1dd9STim J. Robbins 
57*3c87aa1dSDavid Chisnall 	if (table->__collate_load_error || MB_CUR_MAX > 1)
58fd4f1dd9STim J. Robbins 		/*
59fd4f1dd9STim J. Robbins 		 * Locale has no special collating order, could not be
60fd4f1dd9STim J. Robbins 		 * loaded, or has an extended character set; do a fast binary
61fd4f1dd9STim J. Robbins 		 * comparison.
62fd4f1dd9STim J. Robbins 		 */
63fd4f1dd9STim J. Robbins 		return (wcscmp(ws1, ws2));
64fd4f1dd9STim J. Robbins 
65fd4f1dd9STim J. Robbins 	if ((mbs1 = __mbsdup(ws1)) == NULL || (mbs2 = __mbsdup(ws2)) == NULL) {
66fd4f1dd9STim J. Robbins 		/*
67fd4f1dd9STim J. Robbins 		 * Out of memory or illegal wide chars; fall back to wcscmp()
68fd4f1dd9STim J. Robbins 		 * but leave errno indicating the error. Callers that don't
69fd4f1dd9STim J. Robbins 		 * check for error will get a reasonable but often slightly
70fd4f1dd9STim J. Robbins 		 * incorrect result.
71fd4f1dd9STim J. Robbins 		 */
72fd4f1dd9STim J. Robbins 		sverrno = errno;
73fd4f1dd9STim J. Robbins 		free(mbs1);
74fd4f1dd9STim J. Robbins 		errno = sverrno;
75fd4f1dd9STim J. Robbins 		return (wcscmp(ws1, ws2));
76fd4f1dd9STim J. Robbins 	}
77fd4f1dd9STim J. Robbins 
78*3c87aa1dSDavid Chisnall 	diff = strcoll_l(mbs1, mbs2, locale);
79fd4f1dd9STim J. Robbins 	sverrno = errno;
80fd4f1dd9STim J. Robbins 	free(mbs1);
81fd4f1dd9STim J. Robbins 	free(mbs2);
82fd4f1dd9STim J. Robbins 	errno = sverrno;
83fd4f1dd9STim J. Robbins 
84fd4f1dd9STim J. Robbins 	return (diff);
85fd4f1dd9STim J. Robbins }
86fd4f1dd9STim J. Robbins 
87*3c87aa1dSDavid Chisnall int
88*3c87aa1dSDavid Chisnall wcscoll(const wchar_t *ws1, const wchar_t *ws2)
89*3c87aa1dSDavid Chisnall {
90*3c87aa1dSDavid Chisnall 	return wcscoll_l(ws1, ws2, __get_locale());
91*3c87aa1dSDavid Chisnall }
92*3c87aa1dSDavid Chisnall 
93fd4f1dd9STim J. Robbins static char *
94fd4f1dd9STim J. Robbins __mbsdup(const wchar_t *ws)
95fd4f1dd9STim J. Robbins {
96dc763237STim J. Robbins 	static const mbstate_t initial;
97dc763237STim J. Robbins 	mbstate_t st;
98fd4f1dd9STim J. Robbins 	const wchar_t *wcp;
99fd4f1dd9STim J. Robbins 	size_t len;
100fd4f1dd9STim J. Robbins 	char *mbs;
101fd4f1dd9STim J. Robbins 
102fd4f1dd9STim J. Robbins 	wcp = ws;
103dc763237STim J. Robbins 	st = initial;
104dc763237STim J. Robbins 	if ((len = wcsrtombs(NULL, &wcp, 0, &st)) == (size_t)-1)
105fd4f1dd9STim J. Robbins 		return (NULL);
106fd4f1dd9STim J. Robbins 	if ((mbs = malloc(len + 1)) == NULL)
107fd4f1dd9STim J. Robbins 		return (NULL);
108dc763237STim J. Robbins 	st = initial;
109dc763237STim J. Robbins 	wcsrtombs(mbs, &ws, len + 1, &st);
110fd4f1dd9STim J. Robbins 
111fd4f1dd9STim J. Robbins 	return (mbs);
112fd4f1dd9STim J. Robbins }
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