xref: /openbsd-src/sys/ntfs/ntfs_conv.c (revision 43003dfe3ad45d1698bed8a37f2b0f5b14f20d4f)
1 /*	$OpenBSD: ntfs_conv.c,v 1.7 2009/08/13 16:00:53 jasper Exp $	*/
2 /*	$NetBSD: ntfs_conv.c,v 1.1 2002/12/23 17:38:32 jdolecek Exp $	*/
3 
4 /*-
5  * Copyright (c) 2001 The NetBSD Foundation, Inc.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
18  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
19  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
20  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
21  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
22  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
23  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
25  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
26  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27  * POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 /*
31  * File name recode stuff.
32  *
33  * The utf-8 routines were derived from src/lib/libc/locale/utf2.c.
34  */
35 
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/namei.h>
39 #include <sys/proc.h>
40 #include <sys/kernel.h>
41 #include <sys/vnode.h>
42 #include <sys/mount.h>
43 #include <sys/buf.h>
44 #include <sys/file.h>
45 #include <sys/malloc.h>
46 
47 #include <miscfs/specfs/specdev.h>
48 
49 /* #define NTFS_DEBUG 1 */
50 #include <ntfs/ntfs.h>
51 #include <ntfs/ntfsmount.h>
52 #include <ntfs/ntfs_inode.h>
53 #include <ntfs/ntfs_vfsops.h>
54 #include <ntfs/ntfs_subr.h>
55 #include <ntfs/ntfs_compr.h>
56 #include <ntfs/ntfs_ihash.h>
57 
58 /* UTF-8 encoding stuff */
59 
60 static const int _utf_count[16] = {
61         1, 1, 1, 1, 1, 1, 1, 1,
62         0, 0, 0, 0, 2, 2, 3, 0,
63 };
64 
65 /*
66  * Read one wide character off the string, shift the string pointer
67  * and return the character.
68  */
69 wchar
70 ntfs_utf8_wget(const char **str)
71 {
72 	int c;
73 	wchar rune = 0;
74 	const char *s = *str;
75 
76 	c = _utf_count[(s[0] >> 4) & 0xf];
77 	if (c == 0) {
78 		c = 1;
79 		goto encoding_error;
80 	}
81 
82 	switch (c) {
83 	case 1:
84 		rune = s[0] & 0xff;
85 		break;
86 	case 2:
87 		if ((s[1] & 0xc0) != 0x80)
88 			goto encoding_error;
89 		rune = ((s[0] & 0x1F) << 6) | (s[1] & 0x3F);
90 		break;
91 	case 3:
92 		if ((s[1] & 0xC0) != 0x80 || (s[2] & 0xC0) != 0x80)
93 			goto encoding_error;
94 		rune = ((s[0] & 0x1F) << 12) | ((s[1] & 0x3F) << 6)
95 		    | (s[2] & 0x3F);
96 		break;
97 	}
98 
99 encoding_error:
100 	*str = *str + c;
101 	return rune;
102 }
103 
104 /*
105  * Encode wide character and write it to the string. 'n' specifies
106  * how much space there is in the string. Returns number of bytes written
107  * to the target string.
108  */
109 int
110 ntfs_utf8_wput(char *s, size_t n, wchar wc)
111 {
112         if (wc & 0xf800) {
113                 if (n < 3) {
114                         /* bound check failure */
115 			ddprintf(("ntfs_utf8_wput: need 3 bytes\n"));
116                         return 0;
117                 }
118 
119                 s[0] = 0xE0 | ((wc >> 12) & 0x0F);
120                 s[1] = 0x80 | ((wc >> 6) & 0x3F);
121                 s[2] = 0x80 | ((wc) & 0x3F);
122                 return 3;
123         } else {
124                 if (wc & 0x0780) {
125                         if (n < 2) {
126                                 /* bound check failure */
127 				ddprintf(("ntfs_utf8_wput: need 2 bytes\n"));
128                                 return 0;
129                         }
130 
131                         s[0] = 0xC0 | ((wc >> 6) & 0x1F);
132                         s[1] = 0x80 | ((wc) & 0x3F);
133                         return 2;
134                 } else {
135                         if (n < 1) {
136                                 /* bound check failure */
137 				ddprintf(("ntfs_utf8_wput: need 1 byte\n"));
138                                 return 0;
139                         }
140 
141                         s[0] = wc;
142                         return 1;
143                 }
144         }
145 }
146 
147 /*
148  * Compare two wide characters, returning 1, 0, -1 if the first is
149  * bigger, equal or lower than the second.
150  */
151 int
152 ntfs_utf8_wcmp(wchar wc1, wchar wc2)
153 {
154 	/* no conversions needed for utf8 */
155 
156 	if (wc1 == wc2)
157 		return 0;
158 	else
159 		return (int) wc1 - (int) wc2;
160 }
161