summaryrefslogtreecommitdiffstats
path: root/chromium/base/strings/string_split.cc
blob: 210789cd22d0df9b524d40aaeca002ad6e6fb705 (plain)
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
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "base/strings/string_split.h"

#include "base/logging.h"
#include "base/strings/string_util.h"
#include "base/strings/utf_string_conversions.h"
#include "base/third_party/icu/icu_utf.h"

namespace base {

template<typename STR>
static void SplitStringT(const STR& str,
                         const typename STR::value_type s,
                         bool trim_whitespace,
                         std::vector<STR>* r) {
  r->clear();
  size_t last = 0;
  size_t c = str.size();
  for (size_t i = 0; i <= c; ++i) {
    if (i == c || str[i] == s) {
      STR tmp(str, last, i - last);
      if (trim_whitespace)
        TrimWhitespace(tmp, TRIM_ALL, &tmp);
      // Avoid converting an empty or all-whitespace source string into a vector
      // of one empty string.
      if (i != c || !r->empty() || !tmp.empty())
        r->push_back(tmp);
      last = i + 1;
    }
  }
}

void SplitString(const string16& str,
                 char16 c,
                 std::vector<string16>* r) {
  DCHECK(CBU16_IS_SINGLE(c));
  SplitStringT(str, c, true, r);
}

void SplitString(const std::string& str,
                 char c,
                 std::vector<std::string>* r) {
#if CHAR_MIN < 0
  DCHECK(c >= 0);
#endif
  DCHECK(c < 0x7F);
  SplitStringT(str, c, true, r);
}

bool SplitStringIntoKeyValues(
    const std::string& line,
    char key_value_delimiter,
    std::string* key, std::vector<std::string>* values) {
  key->clear();
  values->clear();

  // Find the key string.
  size_t end_key_pos = line.find_first_of(key_value_delimiter);
  if (end_key_pos == std::string::npos) {
    DVLOG(1) << "cannot parse key from line: " << line;
    return false;    // no key
  }
  key->assign(line, 0, end_key_pos);

  // Find the values string.
  std::string remains(line, end_key_pos, line.size() - end_key_pos);
  size_t begin_values_pos = remains.find_first_not_of(key_value_delimiter);
  if (begin_values_pos == std::string::npos) {
    DVLOG(1) << "cannot parse value from line: " << line;
    return false;   // no value
  }
  std::string values_string(remains, begin_values_pos,
                            remains.size() - begin_values_pos);

  // Construct the values vector.
  values->push_back(values_string);
  return true;
}

bool SplitStringIntoKeyValuePairs(const std::string& line,
                                  char key_value_delimiter,
                                  char key_value_pair_delimiter,
                                  StringPairs* key_value_pairs) {
  key_value_pairs->clear();

  std::vector<std::string> pairs;
  SplitString(line, key_value_pair_delimiter, &pairs);

  bool success = true;
  for (size_t i = 0; i < pairs.size(); ++i) {
    // Empty pair. SplitStringIntoKeyValues is more strict about an empty pair
    // line, so continue with the next pair.
    if (pairs[i].empty())
      continue;

    std::string key;
    std::vector<std::string> value;
    if (!SplitStringIntoKeyValues(pairs[i],
                                  key_value_delimiter,
                                  &key, &value)) {
      // Don't return here, to allow for keys without associated
      // values; just record that our split failed.
      success = false;
    }
    DCHECK_LE(value.size(), 1U);
    key_value_pairs->push_back(
        make_pair(key, value.empty() ? std::string() : value[0]));
  }
  return success;
}

template <typename STR>
static void SplitStringUsingSubstrT(const STR& str,
                                    const STR& s,
                                    std::vector<STR>* r) {
  r->clear();
  typename STR::size_type begin_index = 0;
  while (true) {
    const typename STR::size_type end_index = str.find(s, begin_index);
    if (end_index == STR::npos) {
      const STR term = str.substr(begin_index);
      STR tmp;
      TrimWhitespace(term, TRIM_ALL, &tmp);
      r->push_back(tmp);
      return;
    }
    const STR term = str.substr(begin_index, end_index - begin_index);
    STR tmp;
    TrimWhitespace(term, TRIM_ALL, &tmp);
    r->push_back(tmp);
    begin_index = end_index + s.size();
  }
}

void SplitStringUsingSubstr(const string16& str,
                            const string16& s,
                            std::vector<string16>* r) {
  SplitStringUsingSubstrT(str, s, r);
}

void SplitStringUsingSubstr(const std::string& str,
                            const std::string& s,
                            std::vector<std::string>* r) {
  SplitStringUsingSubstrT(str, s, r);
}

void SplitStringDontTrim(const string16& str,
                         char16 c,
                         std::vector<string16>* r) {
  DCHECK(CBU16_IS_SINGLE(c));
  SplitStringT(str, c, false, r);
}

void SplitStringDontTrim(const std::string& str,
                         char c,
                         std::vector<std::string>* r) {
  DCHECK(IsStringUTF8(str));
#if CHAR_MIN < 0
  DCHECK(c >= 0);
#endif
  DCHECK(c < 0x7F);
  SplitStringT(str, c, false, r);
}

template<typename STR>
void SplitStringAlongWhitespaceT(const STR& str, std::vector<STR>* result) {
  result->clear();
  const size_t length = str.length();
  if (!length)
    return;

  bool last_was_ws = false;
  size_t last_non_ws_start = 0;
  for (size_t i = 0; i < length; ++i) {
    switch (str[i]) {
      // HTML 5 defines whitespace as: space, tab, LF, line tab, FF, or CR.
      case L' ':
      case L'\t':
      case L'\xA':
      case L'\xB':
      case L'\xC':
      case L'\xD':
        if (!last_was_ws) {
          if (i > 0) {
            result->push_back(
                str.substr(last_non_ws_start, i - last_non_ws_start));
          }
          last_was_ws = true;
        }
        break;

      default:  // Not a space character.
        if (last_was_ws) {
          last_was_ws = false;
          last_non_ws_start = i;
        }
        break;
    }
  }
  if (!last_was_ws) {
    result->push_back(
        str.substr(last_non_ws_start, length - last_non_ws_start));
  }
}

void SplitStringAlongWhitespace(const string16& str,
                                std::vector<string16>* result) {
  SplitStringAlongWhitespaceT(str, result);
}

void SplitStringAlongWhitespace(const std::string& str,
                                std::vector<std::string>* result) {
  SplitStringAlongWhitespaceT(str, result);
}

}  // namespace base