xref: /linux/fs/unicode/utf8n.h (revision 24bce201d79807b668bf9d9e0aca801c5c0d5f78)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (c) 2014 SGI.
4  * All rights reserved.
5  */
6 
7 #ifndef UTF8NORM_H
8 #define UTF8NORM_H
9 
10 #include <linux/types.h>
11 #include <linux/export.h>
12 #include <linux/string.h>
13 #include <linux/module.h>
14 #include <linux/unicode.h>
15 
16 int utf8version_is_supported(const struct unicode_map *um, unsigned int version);
17 
18 /*
19  * Determine the length of the normalized from of the string,
20  * excluding any terminating NULL byte.
21  * Returns 0 if only ignorable code points are present.
22  * Returns -1 if the input is not valid UTF-8.
23  */
24 ssize_t utf8nlen(const struct unicode_map *um, enum utf8_normalization n,
25 		const char *s, size_t len);
26 
27 /* Needed in struct utf8cursor below. */
28 #define UTF8HANGULLEAF	(12)
29 
30 /*
31  * Cursor structure used by the normalizer.
32  */
33 struct utf8cursor {
34 	const struct unicode_map *um;
35 	enum utf8_normalization n;
36 	const char	*s;
37 	const char	*p;
38 	const char	*ss;
39 	const char	*sp;
40 	unsigned int	len;
41 	unsigned int	slen;
42 	short int	ccc;
43 	short int	nccc;
44 	unsigned char	hangul[UTF8HANGULLEAF];
45 };
46 
47 /*
48  * Initialize a utf8cursor to normalize a string.
49  * Returns 0 on success.
50  * Returns -1 on failure.
51  */
52 int utf8ncursor(struct utf8cursor *u8c, const struct unicode_map *um,
53 		enum utf8_normalization n, const char *s, size_t len);
54 
55 /*
56  * Get the next byte in the normalization.
57  * Returns a value > 0 && < 256 on success.
58  * Returns 0 when the end of the normalization is reached.
59  * Returns -1 if the string being normalized is not valid UTF-8.
60  */
61 extern int utf8byte(struct utf8cursor *u8c);
62 
63 struct utf8data {
64 	unsigned int maxage;
65 	unsigned int offset;
66 };
67 
68 struct utf8data_table {
69 	const unsigned int *utf8agetab;
70 	int utf8agetab_size;
71 
72 	const struct utf8data *utf8nfdicfdata;
73 	int utf8nfdicfdata_size;
74 
75 	const struct utf8data *utf8nfdidata;
76 	int utf8nfdidata_size;
77 
78 	const unsigned char *utf8data;
79 };
80 
81 extern struct utf8data_table utf8_data_table;
82 
83 #endif /* UTF8NORM_H */
84