blob: ae8d2491133c9f19b88599999cf14bf0d66fe1c9
1 | #include <linux/ucs2_string.h> |
2 | #include <linux/module.h> |
3 | |
4 | /* Return the number of unicode characters in data */ |
5 | unsigned long |
6 | ucs2_strnlen(const ucs2_char_t *s, size_t maxlength) |
7 | { |
8 | unsigned long length = 0; |
9 | |
10 | while (*s++ != 0 && length < maxlength) |
11 | length++; |
12 | return length; |
13 | } |
14 | EXPORT_SYMBOL(ucs2_strnlen); |
15 | |
16 | unsigned long |
17 | ucs2_strlen(const ucs2_char_t *s) |
18 | { |
19 | return ucs2_strnlen(s, ~0UL); |
20 | } |
21 | EXPORT_SYMBOL(ucs2_strlen); |
22 | |
23 | /* |
24 | * Return the number of bytes is the length of this string |
25 | * Note: this is NOT the same as the number of unicode characters |
26 | */ |
27 | unsigned long |
28 | ucs2_strsize(const ucs2_char_t *data, unsigned long maxlength) |
29 | { |
30 | return ucs2_strnlen(data, maxlength/sizeof(ucs2_char_t)) * sizeof(ucs2_char_t); |
31 | } |
32 | EXPORT_SYMBOL(ucs2_strsize); |
33 | |
34 | int |
35 | ucs2_strncmp(const ucs2_char_t *a, const ucs2_char_t *b, size_t len) |
36 | { |
37 | while (1) { |
38 | if (len == 0) |
39 | return 0; |
40 | if (*a < *b) |
41 | return -1; |
42 | if (*a > *b) |
43 | return 1; |
44 | if (*a == 0) /* implies *b == 0 */ |
45 | return 0; |
46 | a++; |
47 | b++; |
48 | len--; |
49 | } |
50 | } |
51 | EXPORT_SYMBOL(ucs2_strncmp); |
52 | |
53 | unsigned long |
54 | ucs2_utf8size(const ucs2_char_t *src) |
55 | { |
56 | unsigned long i; |
57 | unsigned long j = 0; |
58 | |
59 | for (i = 0; src[i]; i++) { |
60 | u16 c = src[i]; |
61 | |
62 | if (c >= 0x800) |
63 | j += 3; |
64 | else if (c >= 0x80) |
65 | j += 2; |
66 | else |
67 | j += 1; |
68 | } |
69 | |
70 | return j; |
71 | } |
72 | EXPORT_SYMBOL(ucs2_utf8size); |
73 | |
74 | /* |
75 | * copy at most maxlength bytes of whole utf8 characters to dest from the |
76 | * ucs2 string src. |
77 | * |
78 | * The return value is the number of characters copied, not including the |
79 | * final NUL character. |
80 | */ |
81 | unsigned long |
82 | ucs2_as_utf8(u8 *dest, const ucs2_char_t *src, unsigned long maxlength) |
83 | { |
84 | unsigned int i; |
85 | unsigned long j = 0; |
86 | unsigned long limit = ucs2_strnlen(src, maxlength); |
87 | |
88 | for (i = 0; maxlength && i < limit; i++) { |
89 | u16 c = src[i]; |
90 | |
91 | if (c >= 0x800) { |
92 | if (maxlength < 3) |
93 | break; |
94 | maxlength -= 3; |
95 | dest[j++] = 0xe0 | (c & 0xf000) >> 12; |
96 | dest[j++] = 0x80 | (c & 0x0fc0) >> 6; |
97 | dest[j++] = 0x80 | (c & 0x003f); |
98 | } else if (c >= 0x80) { |
99 | if (maxlength < 2) |
100 | break; |
101 | maxlength -= 2; |
102 | dest[j++] = 0xc0 | (c & 0x7c0) >> 6; |
103 | dest[j++] = 0x80 | (c & 0x03f); |
104 | } else { |
105 | maxlength -= 1; |
106 | dest[j++] = c & 0x7f; |
107 | } |
108 | } |
109 | if (maxlength) |
110 | dest[j] = '\0'; |
111 | return j; |
112 | } |
113 | EXPORT_SYMBOL(ucs2_as_utf8); |
114 |