xref: /freebsd/lib/libc/string/wcsxfrm.c (revision aa0a1e58)
1 /*-
2  * Copyright (c) 1995 Alex Tatmanjants <alex@elvisti.kiev.ua>
3  *		at Electronni Visti IA, Kiev, Ukraine.
4  *			All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 #if 0
30 __FBSDID("FreeBSD: src/lib/libc/string/strxfrm.c,v 1.15 2002/09/06 11:24:06 tjr Exp ");
31 #endif
32 __FBSDID("$FreeBSD$");
33 
34 #include <stdlib.h>
35 #include <string.h>
36 #include <wchar.h>
37 #include "collate.h"
38 
39 static char *__mbsdup(const wchar_t *);
40 
41 /*
42  * Placeholder wcsxfrm() implementation. See wcscoll.c for a description of
43  * the logic used.
44  */
45 size_t
46 wcsxfrm(wchar_t * __restrict dest, const wchar_t * __restrict src, size_t len)
47 {
48 	int prim, sec, l;
49 	size_t slen;
50 	char *mbsrc, *s, *ss;
51 
52 	if (*src == L'\0') {
53 		if (len != 0)
54 			*dest = L'\0';
55 		return (0);
56 	}
57 
58 	if (__collate_load_error || MB_CUR_MAX > 1) {
59 		slen = wcslen(src);
60 		if (len > 0) {
61 			if (slen < len)
62 				wcscpy(dest, src);
63 			else {
64 				wcsncpy(dest, src, len - 1);
65 				dest[len - 1] = L'\0';
66 			}
67 		}
68 		return (slen);
69 	}
70 
71 	mbsrc = __mbsdup(src);
72 	slen = 0;
73 	prim = sec = 0;
74 	ss = s = __collate_substitute(mbsrc);
75 	while (*s != '\0') {
76 		while (*s != '\0' && prim == 0) {
77 			__collate_lookup(s, &l, &prim, &sec);
78 			s += l;
79 		}
80 		if (prim != 0) {
81 			if (len > 1) {
82 				*dest++ = (wchar_t)prim;
83 				len--;
84 			}
85 			slen++;
86 			prim = 0;
87 		}
88 	}
89 	free(ss);
90 	free(mbsrc);
91 	if (len != 0)
92 		*dest = L'\0';
93 
94 	return (slen);
95 }
96 
97 static char *
98 __mbsdup(const wchar_t *ws)
99 {
100 	static const mbstate_t initial;
101 	mbstate_t st;
102 	const wchar_t *wcp;
103 	size_t len;
104 	char *mbs;
105 
106 	wcp = ws;
107 	st = initial;
108 	if ((len = wcsrtombs(NULL, &wcp, 0, &st)) == (size_t)-1)
109 		return (NULL);
110 	if ((mbs = malloc(len + 1)) == NULL)
111 		return (NULL);
112 	st = initial;
113 	wcsrtombs(mbs, &ws, len + 1, &st);
114 
115 	return (mbs);
116 }
117