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
|
// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include "y_absl/strings/match.h"
#include <algorithm>
#include <cstdint>
#include "y_absl/base/internal/endian.h"
#include "y_absl/numeric/bits.h"
#include "y_absl/strings/ascii.h"
#include "y_absl/strings/internal/memutil.h"
namespace y_absl {
Y_ABSL_NAMESPACE_BEGIN
bool EqualsIgnoreCase(y_absl::string_view piece1,
y_absl::string_view piece2) noexcept {
return (piece1.size() == piece2.size() &&
0 == y_absl::strings_internal::memcasecmp(piece1.data(), piece2.data(),
piece1.size()));
// memcasecmp uses y_absl::ascii_tolower().
}
bool StrContainsIgnoreCase(y_absl::string_view haystack,
y_absl::string_view needle) noexcept {
while (haystack.size() >= needle.size()) {
if (StartsWithIgnoreCase(haystack, needle)) return true;
haystack.remove_prefix(1);
}
return false;
}
bool StrContainsIgnoreCase(y_absl::string_view haystack,
char needle) noexcept {
char upper_needle = y_absl::ascii_toupper(static_cast<unsigned char>(needle));
char lower_needle = y_absl::ascii_tolower(static_cast<unsigned char>(needle));
if (upper_needle == lower_needle) {
return StrContains(haystack, needle);
} else {
const char both_cstr[3] = {lower_needle, upper_needle, '\0'};
return haystack.find_first_of(both_cstr) != y_absl::string_view::npos;
}
}
bool StartsWithIgnoreCase(y_absl::string_view text,
y_absl::string_view prefix) noexcept {
return (text.size() >= prefix.size()) &&
EqualsIgnoreCase(text.substr(0, prefix.size()), prefix);
}
bool EndsWithIgnoreCase(y_absl::string_view text,
y_absl::string_view suffix) noexcept {
return (text.size() >= suffix.size()) &&
EqualsIgnoreCase(text.substr(text.size() - suffix.size()), suffix);
}
y_absl::string_view FindLongestCommonPrefix(y_absl::string_view a,
y_absl::string_view b) {
const y_absl::string_view::size_type limit = std::min(a.size(), b.size());
const char* const pa = a.data();
const char* const pb = b.data();
y_absl::string_view::size_type count = (unsigned) 0;
if (Y_ABSL_PREDICT_FALSE(limit < 8)) {
while (Y_ABSL_PREDICT_TRUE(count + 2 <= limit)) {
uint16_t xor_bytes = y_absl::little_endian::Load16(pa + count) ^
y_absl::little_endian::Load16(pb + count);
if (Y_ABSL_PREDICT_FALSE(xor_bytes != 0)) {
if (Y_ABSL_PREDICT_TRUE((xor_bytes & 0xff) == 0)) ++count;
return y_absl::string_view(pa, count);
}
count += 2;
}
if (Y_ABSL_PREDICT_TRUE(count != limit)) {
if (Y_ABSL_PREDICT_TRUE(pa[count] == pb[count])) ++count;
}
return y_absl::string_view(pa, count);
}
do {
uint64_t xor_bytes = y_absl::little_endian::Load64(pa + count) ^
y_absl::little_endian::Load64(pb + count);
if (Y_ABSL_PREDICT_FALSE(xor_bytes != 0)) {
count += static_cast<uint64_t>(y_absl::countr_zero(xor_bytes) >> 3);
return y_absl::string_view(pa, count);
}
count += 8;
} while (Y_ABSL_PREDICT_TRUE(count + 8 < limit));
count = limit - 8;
uint64_t xor_bytes = y_absl::little_endian::Load64(pa + count) ^
y_absl::little_endian::Load64(pb + count);
if (Y_ABSL_PREDICT_TRUE(xor_bytes != 0)) {
count += static_cast<uint64_t>(y_absl::countr_zero(xor_bytes) >> 3);
return y_absl::string_view(pa, count);
}
return y_absl::string_view(pa, limit);
}
y_absl::string_view FindLongestCommonSuffix(y_absl::string_view a,
y_absl::string_view b) {
const y_absl::string_view::size_type limit = std::min(a.size(), b.size());
if (limit == 0) return y_absl::string_view();
const char* pa = a.data() + a.size() - 1;
const char* pb = b.data() + b.size() - 1;
y_absl::string_view::size_type count = (unsigned) 0;
while (count < limit && *pa == *pb) {
--pa;
--pb;
++count;
}
return y_absl::string_view(++pa, count);
}
Y_ABSL_NAMESPACE_END
} // namespace y_absl
|
