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
|
// Copyright Vespa.ai. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
#include "foldedstringcompare.h"
#include <vespa/vespalib/text/utf8.h>
#include <vespa/vespalib/text/lowercase.h>
using vespalib::LowerCase;
using vespalib::Utf8ReaderForZTS;
namespace search {
using Utf32VectorRef = std::reference_wrapper<const std::vector<uint32_t>>;
namespace foldedstringcompare {
class Utf32Reader {
using Iterator = typename std::vector<uint32_t>::const_iterator;
Iterator _cur;
Iterator _end;
public:
Utf32Reader(const std::vector<uint32_t>& key)
: _cur(key.begin()),
_end(key.end())
{
}
bool hasMore() const noexcept { return _cur != _end; }
uint32_t getChar() noexcept { return *_cur++; }
};
template <typename T> class FoldableStringHelper;
template <> class FoldableStringHelper<const char*>
{
public:
using Reader = Utf8ReaderForZTS;
};
template <> class FoldableStringHelper<Utf32VectorRef>
{
public:
using Reader = Utf32Reader;
};
}
template <typename KeyType>
using Reader = typename foldedstringcompare::FoldableStringHelper<KeyType>::Reader;
size_t
FoldedStringCompare::
size(const char *key)
{
return Utf8ReaderForZTS::countChars(key);
}
template <bool fold_lhs, bool fold_rhs, detail::FoldableString KeyType, detail::FoldableString OKeyType>
int
FoldedStringCompare::
compareFolded(KeyType key, OKeyType okey)
{
Reader<KeyType> kreader(key);
Reader<OKeyType> oreader(okey);
for (;;) {
if (!kreader.hasMore()) {
return oreader.hasMore() ? -1 : 0;
} else if (!oreader.hasMore()) {
return 1;
}
uint32_t kval = fold_lhs ? LowerCase::convert(kreader.getChar()) : kreader.getChar();
uint32_t oval = fold_rhs ? LowerCase::convert(oreader.getChar()) : oreader.getChar();
if (kval != oval) {
if (kval < oval) {
return -1;
} else {
return 1;
}
}
}
}
template <bool fold_lhs, bool fold_rhs>
int
FoldedStringCompare::
compareFoldedPrefix(const char *key, const char *okey, size_t prefixLen)
{
Utf8ReaderForZTS kreader(key);
Utf8ReaderForZTS oreader(okey);
for (size_t j = 0; j < prefixLen; ++j ) {
uint32_t kval = fold_lhs ? LowerCase::convert(kreader.getChar()) : kreader.getChar();
uint32_t oval = fold_rhs ? LowerCase::convert(oreader.getChar()) : oreader.getChar();
if (kval != oval) {
if (kval < oval) {
return -1;
} else {
return 1;
}
}
if (kval == 0) {
return 0;
}
}
// reached end of prefix
return 0;
}
int
FoldedStringCompare::
comparePrefix(const char *key, const char *okey, size_t prefixLen)
{
int res = compareFoldedPrefix<true, true>(key, okey, prefixLen);
if (res != 0) {
return res;
}
return compareFoldedPrefix<false, false>(key, okey, prefixLen);
}
int
FoldedStringCompare::
compare(const char *key, const char *okey)
{
int res = compareFolded<true, true>(key, okey);
if (res != 0) {
return res;
}
return strcmp(key, okey);
}
template int FoldedStringCompare::compareFolded<false, false>(const char* key, Utf32VectorRef okey);
template int FoldedStringCompare::compareFolded<true, false>(const char* key, Utf32VectorRef okey);
template int FoldedStringCompare::compareFolded<false, false>(Utf32VectorRef key, const char* okey);
template int FoldedStringCompare::compareFolded<false, true>(Utf32VectorRef key, const char* okey);
template int FoldedStringCompare::compareFolded<false, false>(const char* key, const char* okey);
template int FoldedStringCompare::compareFolded<false, true>(const char* key, const char* okey);
template int FoldedStringCompare::compareFolded<true, false>(const char* key, const char* okey);
template int FoldedStringCompare::compareFolded<true, true>(const char* key, const char* okey);
template int FoldedStringCompare::compareFoldedPrefix<false, false>(const char* key, const char* okey, size_t prefixLen);
template int FoldedStringCompare::compareFoldedPrefix<false, true>(const char* key, const char* okey, size_t prefixLen);
template int FoldedStringCompare::compareFoldedPrefix<true, false>(const char* key, const char* okey, size_t prefixLen);
template int FoldedStringCompare::compareFoldedPrefix<true, true>(const char* key, const char* okey, size_t prefixLen);
} // namespace search
|
