strings.cpp revision 4f71319df011d796a60a43fc1bc68e16fbf7d321 
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 "android-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
82// These cases are probably the norm, so we mark them extern in the header to
83// aid compile time and binary size.
84template std::string Join(const std::vector<std::string>&, char);
85template std::string Join(const std::vector<const char*>&, char);
86template std::string Join(const std::vector<std::string>&, const std::string&);
87template std::string Join(const std::vector<const char*>&, const std::string&);
88
89bool StartsWith(const std::string& s, const char* prefix) {
90  return s.compare(0, strlen(prefix), prefix) == 0;
91}
92
93bool EndsWith(const std::string& s, const char* suffix) {
94  size_t suffix_length = strlen(suffix);
95  size_t string_length = s.size();
96  if (suffix_length > string_length) {
97    return false;
98  }
99  size_t offset = string_length - suffix_length;
100  return s.compare(offset, suffix_length, suffix) == 0;
101}
102
103}  // namespace base
104}  // namespace android
105