|
1 /* |
|
2 * Copyright (c) 2004, Oracle and/or its affiliates. All rights reserved. |
|
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
|
4 * |
|
5 * This code is free software; you can redistribute it and/or modify it |
|
6 * under the terms of the GNU General Public License version 2 only, as |
|
7 * published by the Free Software Foundation. Oracle designates this |
|
8 * particular file as subject to the "Classpath" exception as provided |
|
9 * by Oracle in the LICENSE file that accompanied this code. |
|
10 * |
|
11 * This code is distributed in the hope that it will be useful, but WITHOUT |
|
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
|
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
|
14 * version 2 for more details (a copy is included in the LICENSE file that |
|
15 * accompanied this code). |
|
16 * |
|
17 * You should have received a copy of the GNU General Public License version |
|
18 * 2 along with this work; if not, write to the Free Software Foundation, |
|
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
|
20 * |
|
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
|
22 * or visit www.oracle.com if you need additional information or have any |
|
23 * questions. |
|
24 */ |
|
25 |
|
26 |
|
27 /** |
|
28 * Determine length of this Standard UTF-8 in Modified UTF-8. |
|
29 * Validation is done of the basic UTF encoding rules, returns |
|
30 * length (no change) when errors are detected in the UTF encoding. |
|
31 * |
|
32 * Note: Accepts Modified UTF-8 also, no verification on the |
|
33 * correctness of Standard UTF-8 is done. e,g, 0xC080 input is ok. |
|
34 */ |
|
35 int |
|
36 modifiedUtf8LengthOfUtf8(char* string, int length) { |
|
37 int new_length; |
|
38 int i; |
|
39 |
|
40 new_length = 0; |
|
41 for ( i = 0 ; i < length ; i++ ) { |
|
42 unsigned byte; |
|
43 |
|
44 byte = (unsigned char)string[i]; |
|
45 if ( (byte & 0x80) == 0 ) { /* 1byte encoding */ |
|
46 new_length++; |
|
47 if ( byte == 0 ) { |
|
48 new_length++; /* We gain one byte in length on NULL bytes */ |
|
49 } |
|
50 } else if ( (byte & 0xE0) == 0xC0 ) { /* 2byte encoding */ |
|
51 /* Check encoding of following bytes */ |
|
52 if ( (i+1) >= length || (string[i+1] & 0xC0) != 0x80 ) { |
|
53 break; /* Error condition */ |
|
54 } |
|
55 i++; /* Skip next byte */ |
|
56 new_length += 2; |
|
57 } else if ( (byte & 0xF0) == 0xE0 ) { /* 3byte encoding */ |
|
58 /* Check encoding of following bytes */ |
|
59 if ( (i+2) >= length || (string[i+1] & 0xC0) != 0x80 |
|
60 || (string[i+2] & 0xC0) != 0x80 ) { |
|
61 break; /* Error condition */ |
|
62 } |
|
63 i += 2; /* Skip next two bytes */ |
|
64 new_length += 3; |
|
65 } else if ( (byte & 0xF8) == 0xF0 ) { /* 4byte encoding */ |
|
66 /* Check encoding of following bytes */ |
|
67 if ( (i+3) >= length || (string[i+1] & 0xC0) != 0x80 |
|
68 || (string[i+2] & 0xC0) != 0x80 |
|
69 || (string[i+3] & 0xC0) != 0x80 ) { |
|
70 break; /* Error condition */ |
|
71 } |
|
72 i += 3; /* Skip next 3 bytes */ |
|
73 new_length += 6; /* 4byte encoding turns into 2 3byte ones */ |
|
74 } else { |
|
75 break; /* Error condition */ |
|
76 } |
|
77 } |
|
78 if ( i != length ) { |
|
79 /* Error in finding new length, return old length so no conversion */ |
|
80 /* FIXUP: ERROR_MESSAGE? */ |
|
81 return length; |
|
82 } |
|
83 return new_length; |
|
84 } |
|
85 |
|
86 /* |
|
87 * Convert Standard UTF-8 to Modified UTF-8. |
|
88 * Assumes the UTF-8 encoding was validated by modifiedLength() above. |
|
89 * |
|
90 * Note: Accepts Modified UTF-8 also, no verification on the |
|
91 * correctness of Standard UTF-8 is done. e,g, 0xC080 input is ok. |
|
92 */ |
|
93 void |
|
94 convertUtf8ToModifiedUtf8(char *string, int length, char *new_string, int new_length) |
|
95 { |
|
96 int i; |
|
97 int j; |
|
98 |
|
99 j = 0; |
|
100 for ( i = 0 ; i < length ; i++ ) { |
|
101 unsigned byte1; |
|
102 |
|
103 byte1 = (unsigned char)string[i]; |
|
104 |
|
105 /* NULL bytes and bytes starting with 11110xxx are special */ |
|
106 if ( (byte1 & 0x80) == 0 ) { /* 1byte encoding */ |
|
107 if ( byte1 == 0 ) { |
|
108 /* Bits out: 11000000 10000000 */ |
|
109 new_string[j++] = (char)0xC0; |
|
110 new_string[j++] = (char)0x80; |
|
111 } else { |
|
112 /* Single byte */ |
|
113 new_string[j++] = byte1; |
|
114 } |
|
115 } else if ( (byte1 & 0xE0) == 0xC0 ) { /* 2byte encoding */ |
|
116 new_string[j++] = byte1; |
|
117 new_string[j++] = string[++i]; |
|
118 } else if ( (byte1 & 0xF0) == 0xE0 ) { /* 3byte encoding */ |
|
119 new_string[j++] = byte1; |
|
120 new_string[j++] = string[++i]; |
|
121 new_string[j++] = string[++i]; |
|
122 } else if ( (byte1 & 0xF8) == 0xF0 ) { /* 4byte encoding */ |
|
123 /* Beginning of 4byte encoding, turn into 2 3byte encodings */ |
|
124 unsigned byte2, byte3, byte4, u21; |
|
125 |
|
126 /* Bits in: 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx */ |
|
127 byte2 = (unsigned char)string[++i]; |
|
128 byte3 = (unsigned char)string[++i]; |
|
129 byte4 = (unsigned char)string[++i]; |
|
130 /* Reconstruct full 21bit value */ |
|
131 u21 = (byte1 & 0x07) << 18; |
|
132 u21 += (byte2 & 0x3F) << 12; |
|
133 u21 += (byte3 & 0x3F) << 6; |
|
134 u21 += (byte4 & 0x3F); |
|
135 /* Bits out: 11101101 1010xxxx 10xxxxxx */ |
|
136 new_string[j++] = (char)0xED; |
|
137 new_string[j++] = 0xA0 + (((u21 >> 16) - 1) & 0x0F); |
|
138 new_string[j++] = 0x80 + ((u21 >> 10) & 0x3F); |
|
139 /* Bits out: 11101101 1011xxxx 10xxxxxx */ |
|
140 new_string[j++] = (char)0xED; |
|
141 new_string[j++] = 0xB0 + ((u21 >> 6) & 0x0F); |
|
142 new_string[j++] = byte4; |
|
143 } |
|
144 } |
|
145 new_string[j] = 0; |
|
146 } |