1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
|
// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
// vim: ts=8 sw=2 smarttab
/*
* Ceph - scalable distributed file system
*
* Copyright (C) 2011 New Dream Network
*
* This is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License version 2.1, as published by the Free Software
* Foundation. See file COPYING.
*
*/
#include "common/utf8.h"
#include <string.h>
/*
* http://www.unicode.org/versions/Unicode6.0.0/ch03.pdf - page 94
*
* Table 3-7. Well-Formed UTF-8 Byte Sequences
*
* +--------------------+------------+-------------+------------+-------------+
* | Code Points | First Byte | Second Byte | Third Byte | Fourth Byte |
* +--------------------+------------+-------------+------------+-------------+
* | U+0000..U+007F | 00..7F | | | |
* +--------------------+------------+-------------+------------+-------------+
* | U+0080..U+07FF | C2..DF | 80..BF | | |
* +--------------------+------------+-------------+------------+-------------+
* | U+0800..U+0FFF | E0 | A0..BF | 80..BF | |
* +--------------------+------------+-------------+------------+-------------+
* | U+1000..U+CFFF | E1..EC | 80..BF | 80..BF | |
* +--------------------+------------+-------------+------------+-------------+
* | U+D000..U+D7FF | ED | 80..9F | 80..BF | |
* +--------------------+------------+-------------+------------+-------------+
* | U+E000..U+FFFF | EE..EF | 80..BF | 80..BF | |
* +--------------------+------------+-------------+------------+-------------+
* | U+10000..U+3FFFF | F0 | 90..BF | 80..BF | 80..BF |
* +--------------------+------------+-------------+------------+-------------+
* | U+40000..U+FFFFF | F1..F3 | 80..BF | 80..BF | 80..BF |
* +--------------------+------------+-------------+------------+-------------+
* | U+100000..U+10FFFF | F4 | 80..8F | 80..BF | 80..BF |
* +--------------------+------------+-------------+------------+-------------+
*/
static int high_bits_set(int c)
{
int ret = 0;
while (1) {
if ((c & 0x80) != 0x080)
break;
c <<= 1;
++ret;
}
return ret;
}
/* Encode a 31-bit UTF8 code point to 'buf'.
* Assumes buf is of size MAX_UTF8_SZ
* Returns -1 on failure; number of bytes in the encoded value otherwise.
*/
int encode_utf8(unsigned long u, unsigned char *buf)
{
/* Unroll loop for common code points */
if (u <= 0x0000007F) {
buf[0] = u;
return 1;
} else if (u <= 0x000007FF) {
buf[0] = 0xC0 | (u >> 6);
buf[1] = 0x80 | (u & 0x3F);
return 2;
} else if (u <= 0x0000FFFF) {
buf[0] = 0xE0 | (u >> 12);
buf[1] = 0x80 | ((u >> 6) & 0x3F);
buf[2] = 0x80 | (u & 0x3F);
return 3;
} else if (u <= 0x001FFFFF) {
buf[0] = 0xF0 | (u >> 18);
buf[1] = 0x80 | ((u >> 12) & 0x3F);
buf[2] = 0x80 | ((u >> 6) & 0x3F);
buf[3] = 0x80 | (u & 0x3F);
return 4;
} else {
/* Rare/illegal code points */
if (u <= 0x03FFFFFF) {
for (int i = 4; i >= 1; --i) {
buf[i] = 0x80 | (u & 0x3F);
u >>= 6;
}
buf[0] = 0xF8 | u;
return 5;
} else if (u <= 0x7FFFFFFF) {
for (int i = 5; i >= 1; --i) {
buf[i] = 0x80 | (u & 0x3F);
u >>= 6;
}
buf[0] = 0xFC | u;
return 6;
}
return -1;
}
}
/*
* Decode a UTF8 character from an array of bytes. Return character code.
* Upon error, return INVALID_UTF8_CHAR.
*/
unsigned long decode_utf8(unsigned char *buf, int nbytes)
{
unsigned long code;
int i, j;
if (nbytes <= 0)
return INVALID_UTF8_CHAR;
if (nbytes == 1) {
if (buf[0] >= 0x80)
return INVALID_UTF8_CHAR;
return buf[0];
}
i = high_bits_set(buf[0]);
if (i != nbytes)
return INVALID_UTF8_CHAR;
code = buf[0] & (0xff >> i);
for (j = 1; j < nbytes; ++j) {
if ((buf[j] & 0xc0) != 0x80)
return INVALID_UTF8_CHAR;
code = (code << 6) | (buf[j] & 0x3f);
}
// Check for invalid code points
if (code == 0xFFFE)
return INVALID_UTF8_CHAR;
if (code == 0xFFFF)
return INVALID_UTF8_CHAR;
if (code >= 0xD800 && code <= 0xDFFF)
return INVALID_UTF8_CHAR;
return code;
}
int check_utf8(const char *buf, int len)
{
/*
* "char" is "signed" on x86 but "unsigned" on aarch64 by default.
* Below code depends on signed/unsigned comparisons, define an
* unsigned buffer explicitly to fix the gap.
*/
const unsigned char *bufu = (const unsigned char *)buf;
int err_pos = 1;
while (len) {
int nbytes;
unsigned char byte1 = bufu[0];
/* 00..7F */
if (byte1 <= 0x7F) {
nbytes = 1;
/* C2..DF, 80..BF */
} else if (len >= 2 && byte1 >= 0xC2 && byte1 <= 0xDF &&
(signed char)bufu[1] <= (signed char)0xBF) {
nbytes = 2;
} else if (len >= 3) {
unsigned char byte2 = bufu[1];
/* Is byte2, byte3 between 0x80 ~ 0xBF */
int byte2_ok = (signed char)byte2 <= (signed char)0xBF;
int byte3_ok = (signed char)bufu[2] <= (signed char)0xBF;
if (byte2_ok && byte3_ok &&
/* E0, A0..BF, 80..BF */
((byte1 == 0xE0 && byte2 >= 0xA0) ||
/* E1..EC, 80..BF, 80..BF */
(byte1 >= 0xE1 && byte1 <= 0xEC) ||
/* ED, 80..9F, 80..BF */
(byte1 == 0xED && byte2 <= 0x9F) ||
/* EE..EF, 80..BF, 80..BF */
(byte1 >= 0xEE && byte1 <= 0xEF))) {
nbytes = 3;
} else if (len >= 4) {
/* Is byte4 between 0x80 ~ 0xBF */
int byte4_ok = (signed char)bufu[3] <= (signed char)0xBF;
if (byte2_ok && byte3_ok && byte4_ok &&
/* F0, 90..BF, 80..BF, 80..BF */
((byte1 == 0xF0 && byte2 >= 0x90) ||
/* F1..F3, 80..BF, 80..BF, 80..BF */
(byte1 >= 0xF1 && byte1 <= 0xF3) ||
/* F4, 80..8F, 80..BF, 80..BF */
(byte1 == 0xF4 && byte2 <= 0x8F))) {
nbytes = 4;
} else {
return err_pos;
}
} else {
return err_pos;
}
} else {
return err_pos;
}
len -= nbytes;
err_pos += nbytes;
bufu += nbytes;
}
return 0;
}
int check_utf8_cstr(const char *buf)
{
return check_utf8(buf, strlen(buf));
}
int is_control_character(int c)
{
return (((c != 0) && (c < 0x20)) || (c == 0x7f));
}
int check_for_control_characters(const char *buf, int len)
{
int i;
for (i = 0; i < len; ++i) {
if (is_control_character((int)(unsigned char)buf[i])) {
return i + 1;
}
}
return 0;
}
int check_for_control_characters_cstr(const char *buf)
{
return check_for_control_characters(buf, strlen(buf));
}
|
