strings.cpp revision 8d5fa6da44d56511b3e173bc463cbc65ff221b4a 
1/*
2 * Copyright (C) 2015 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include "base/strings.h"
18
19#include <stdlib.h>
20#include <string.h>
21
22#include <string>
23#include <vector>
24
25namespace android {
26namespace base {
27
28#define CHECK_NE(a, b) \
29  if ((a) == (b)) abort();
30
31std::vector<std::string> Split(const std::string& s,
32                               const std::string& delimiters) {
33  CHECK_NE(delimiters.size(), 0U);
34
35  std::vector<std::string> result;
36
37  size_t base = 0;
38  size_t found;
39  do {
40    found = s.find_first_of(delimiters, base);
41    result.push_back(s.substr(base, found - base));
42    base = found + 1;
43  } while (found != s.npos);
44
45  return result;
46}
47
48std::string Trim(const std::string& s) {
49  std::string result;
50
51  if (s.size() == 0) {
52    return result;
53  }
54
55  size_t start_index = 0;
56  size_t end_index = s.size() - 1;
57
58  // Skip initial whitespace.
59  while (start_index < s.size()) {
60    if (!isspace(s[start_index])) {
61      break;
62    }
63    start_index++;
64  }
65
66  // Skip terminating whitespace.
67  while (end_index >= start_index) {
68    if (!isspace(s[end_index])) {
69      break;
70    }
71    end_index--;
72  }
73
74  // All spaces, no beef.
75  if (end_index < start_index) {
76    return "";
77  }
78  // Start_index is the first non-space, end_index is the last one.
79  return s.substr(start_index, end_index - start_index + 1);
80}
81
82template <typename StringT>
83std::string Join(const std::vector<StringT>& strings, char separator) {
84  if (strings.empty()) {
85    return "";
86  }
87
88  std::string result(strings[0]);
89  for (size_t i = 1; i < strings.size(); ++i) {
90    result += separator;
91    result += strings[i];
92  }
93  return result;
94}
95
96// Explicit instantiations.
97template std::string Join<std::string>(const std::vector<std::string>& strings,
98                                       char separator);
99template std::string Join<const char*>(const std::vector<const char*>& strings,
100                                       char separator);
101
102bool StartsWith(const std::string& s, const char* prefix) {
103  return s.compare(0, strlen(prefix), prefix) == 0;
104}
105
106bool EndsWith(const std::string& s, const char* suffix) {
107  size_t suffix_length = strlen(suffix);
108  size_t string_length = s.size();
109  if (suffix_length > string_length) {
110    return false;
111  }
112  size_t offset = string_length - suffix_length;
113  return s.compare(offset, suffix_length, suffix) == 0;
114}
115
116}  // namespace base
117}  // namespace android
118