1 /*
2 * Copyright (C) 2010 Regents of the University of Michigan
3 *
4 * This program is free software: you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation, either version 3 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program. If not, see <http://www.gnu.org/licenses/>.
16 */
17
18 #include "STLUtilities.h"
19
20 namespace STLUtilities
21 {
22
23 //
24 // Split the string input into words delimited by the character
25 // delimiter. For a given number of input delimiters, result.size()
26 // will not change, regardless of the data in between the delimiters.
27 //
28 // Refactor this to pre-allocate the word that we place data into,
29 // then we have minimal data copy.
30 //
Tokenize(std::vector<std::string> & result,const char * input,char delimiter)31 int Tokenize(std::vector<std::string> &result, const char *input, char delimiter)
32 {
33 if (*input=='\0')
34 {
35 result.clear();
36 result.resize(1); // one word, and it is empty
37 return 0;
38 }
39
40 size_t wordCount = 1;
41
42 // since input is non-empty, we know we will have at least
43 // one word, so we allocate it here, and begin to fill it in
44 if (result.size()<wordCount) result.resize(1);
45 else result[0].clear();
46
47 std::string *word = &result[0];
48
49 while (*input)
50 {
51 if (*input==delimiter)
52 {
53 // we got a delimeter, and since an empty word following
54 // a delimeter still counts as a word, we allocate it here
55 wordCount++;
56 if (result.size()<wordCount) result.resize(wordCount);
57 else
58 {
59 result[wordCount-1].clear();
60 }
61 word = &result[wordCount-1];
62 }
63 else
64 {
65 // save the char in this word
66 word->push_back(*input);
67 }
68 input++;
69 }
70
71 if (wordCount < result.size()) result.resize(wordCount); // potentially truncate to wordCount elements
72
73 return result.size();
74 }
75
76 } // end of namespace STLUtilities
77