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
|
/*
**********************************************************************
* Copyright (C) 2005-2012, International Business Machines
* Corporation and others. All Rights Reserved.
**********************************************************************
*/
#include "unicode/utypes.h"
#if !UCONFIG_NO_CONVERSION
#include "csrucode.h"
#include "csmatch.h"
U_NAMESPACE_BEGIN
CharsetRecog_Unicode::~CharsetRecog_Unicode()
{
// nothing to do
}
CharsetRecog_UTF_16_BE::~CharsetRecog_UTF_16_BE()
{
// nothing to do
}
const char *CharsetRecog_UTF_16_BE::getName() const
{
return "UTF-16BE";
}
UBool CharsetRecog_UTF_16_BE::match(InputText* textIn, CharsetMatch *results) const
{
const uint8_t *input = textIn->fRawInput;
int32_t confidence = 0;
if (input[0] == 0xFE && input[1] == 0xFF) {
confidence = 100;
}
// TODO: Do some statastics to check for unsigned UTF-16BE
results->set(textIn, this, confidence);
return (confidence > 0);
}
CharsetRecog_UTF_16_LE::~CharsetRecog_UTF_16_LE()
{
// nothing to do
}
const char *CharsetRecog_UTF_16_LE::getName() const
{
return "UTF-16LE";
}
UBool CharsetRecog_UTF_16_LE::match(InputText* textIn, CharsetMatch *results) const
{
const uint8_t *input = textIn->fRawInput;
int32_t confidence = 0;
if (input[0] == 0xFF && input[1] == 0xFE && (input[2] != 0x00 || input[3] != 0x00)) {
confidence = 100;
}
// TODO: Do some statastics to check for unsigned UTF-16LE
results->set(textIn, this, confidence);
return (confidence > 0);
}
CharsetRecog_UTF_32::~CharsetRecog_UTF_32()
{
// nothing to do
}
UBool CharsetRecog_UTF_32::match(InputText* textIn, CharsetMatch *results) const
{
const uint8_t *input = textIn->fRawInput;
int32_t limit = (textIn->fRawLength / 4) * 4;
int32_t numValid = 0;
int32_t numInvalid = 0;
bool hasBOM = FALSE;
int32_t confidence = 0;
if (getChar(input, 0) == 0x0000FEFFUL) {
hasBOM = TRUE;
}
for(int32_t i = 0; i < limit; i += 4) {
int32_t ch = getChar(input, i);
if (ch < 0 || ch >= 0x10FFFF || (ch >= 0xD800 && ch <= 0xDFFF)) {
numInvalid += 1;
} else {
numValid += 1;
}
}
// Cook up some sort of confidence score, based on presense of a BOM
// and the existence of valid and/or invalid multi-byte sequences.
if (hasBOM && numInvalid==0) {
confidence = 100;
} else if (hasBOM && numValid > numInvalid*10) {
confidence = 80;
} else if (numValid > 3 && numInvalid == 0) {
confidence = 100;
} else if (numValid > 0 && numInvalid == 0) {
confidence = 80;
} else if (numValid > numInvalid*10) {
// Probably corruput UTF-32BE data. Valid sequences aren't likely by chance.
confidence = 25;
}
results->set(textIn, this, confidence);
return (confidence > 0);
}
CharsetRecog_UTF_32_BE::~CharsetRecog_UTF_32_BE()
{
// nothing to do
}
const char *CharsetRecog_UTF_32_BE::getName() const
{
return "UTF-32BE";
}
int32_t CharsetRecog_UTF_32_BE::getChar(const uint8_t *input, int32_t index) const
{
return input[index + 0] << 24 | input[index + 1] << 16 |
input[index + 2] << 8 | input[index + 3];
}
CharsetRecog_UTF_32_LE::~CharsetRecog_UTF_32_LE()
{
// nothing to do
}
const char *CharsetRecog_UTF_32_LE::getName() const
{
return "UTF-32LE";
}
int32_t CharsetRecog_UTF_32_LE::getChar(const uint8_t *input, int32_t index) const
{
return input[index + 3] << 24 | input[index + 2] << 16 |
input[index + 1] << 8 | input[index + 0];
}
U_NAMESPACE_END
#endif
|
