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
|
// Copyright Contributors to the DNF5 project.
// Copyright Contributors to the libdnf project.
// SPDX-License-Identifier: LGPL-2.1-or-later
//
// This file is part of libdnf: https://github.com/rpm-software-management/libdnf/
//
// Libdnf is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 2.1 of the License, or
// (at your option) any later version.
//
// Libdnf is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with libdnf. If not, see <https://www.gnu.org/licenses/>.
#include "string.hpp"
namespace libdnf5::utils::string {
static std::vector<std::string> split_impl(
const std::string & str, const std::string & delimiter, std::size_t limit, bool from_right) {
std::vector<std::string> result;
// For an empty input string, return a vector with one empty token.
if (str.empty()) {
result.emplace_back("");
return result;
}
if (limit < 2) {
result.emplace_back(str);
return result;
}
const auto delim_length = delimiter.size();
// Count the number of tokens on the input.
std::size_t tokens_count = 1;
for (auto pos = str.find(delimiter); pos != std::string::npos; pos = str.find(delimiter, pos + delim_length)) {
++tokens_count;
}
auto delim_pos = str.find(delimiter);
// The resulting number of tokens must be less than or equal to the limit.
if (tokens_count > limit) {
if (from_right) {
// For right-split, skip the left excess delimiters.
for (; tokens_count > limit; --tokens_count) {
delim_pos = str.find(delimiter, delim_pos + delim_length);
}
} else {
// For left-split, adjust the tokens_count.
tokens_count = limit;
}
}
// Reserve memory to avoid realocations.
result.reserve(tokens_count);
// Split the input string.
std::size_t token_pos = 0;
while (--tokens_count != 0) {
result.emplace_back(str, token_pos, delim_pos - token_pos);
token_pos = delim_pos + delim_length;
delim_pos = str.find(delimiter, token_pos);
}
// Put the rest as the last token.
result.emplace_back(str, token_pos);
return result;
}
std::vector<std::string> rsplit(const std::string & str, const std::string & delimiter, std::size_t limit) {
return split_impl(str, delimiter, limit, true);
}
std::vector<std::string> split(const std::string & str, const std::string & delimiter, std::size_t limit) {
return split_impl(str, delimiter, limit, false);
}
} // namespace libdnf5::utils::string
|
