platform_system_core/base/strings.cpp

125 lines
3.0 KiB
C++

/*
* Copyright (C) 2015 The Android Open Source Project
*
* 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
*
* http://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 "base/strings.h"
#include <stdlib.h>
#include <string.h>
#include <string>
#include <vector>
namespace android {
namespace base {
#define CHECK_NE(a, b) \
if ((a) == (b)) abort();
std::vector<std::string> Split(const std::string& s,
const std::string& delimiters) {
CHECK_NE(delimiters.size(), 0U);
std::vector<std::string> split;
if (s.size() == 0) {
// Split("", d) returns {} rather than {""}.
return split;
}
size_t base = 0;
size_t found;
do {
found = s.find_first_of(delimiters, base);
if (found != base) {
split.push_back(s.substr(base, found - base));
}
base = found + 1;
} while (found != s.npos);
return split;
}
std::string Trim(const std::string& s) {
std::string result;
if (s.size() == 0) {
return result;
}
size_t start_index = 0;
size_t end_index = s.size() - 1;
// Skip initial whitespace.
while (start_index < s.size()) {
if (!isspace(s[start_index])) {
break;
}
start_index++;
}
// Skip terminating whitespace.
while (end_index >= start_index) {
if (!isspace(s[end_index])) {
break;
}
end_index--;
}
// All spaces, no beef.
if (end_index < start_index) {
return "";
}
// Start_index is the first non-space, end_index is the last one.
return s.substr(start_index, end_index - start_index + 1);
}
template <typename StringT>
std::string Join(const std::vector<StringT>& strings, char separator) {
if (strings.empty()) {
return "";
}
std::string result(strings[0]);
for (size_t i = 1; i < strings.size(); ++i) {
result += separator;
result += strings[i];
}
return result;
}
// Explicit instantiations.
template std::string Join<std::string>(const std::vector<std::string>& strings,
char separator);
template std::string Join<const char*>(const std::vector<const char*>& strings,
char separator);
bool StartsWith(const std::string& s, const char* prefix) {
return s.compare(0, strlen(prefix), prefix) == 0;
}
bool EndsWith(const std::string& s, const char* suffix) {
size_t suffix_length = strlen(suffix);
size_t string_length = s.size();
if (suffix_length > string_length) {
return false;
}
size_t offset = string_length - suffix_length;
return s.compare(offset, suffix_length, suffix) == 0;
}
} // namespace base
} // namespace android