Line | Count | Source |
1 | | // Copyright 1999-2005 The RE2 Authors. All Rights Reserved. |
2 | | // Use of this source code is governed by a BSD-style |
3 | | // license that can be found in the LICENSE file. |
4 | | |
5 | | #include "util/strutil.h" |
6 | | |
7 | | namespace re2 { |
8 | | |
9 | 3.10k | void PrefixSuccessor(std::string* prefix) { |
10 | | // We can increment the last character in the string and be done |
11 | | // unless that character is 255, in which case we have to erase the |
12 | | // last character and increment the previous character, unless that |
13 | | // is 255, etc. If the string is empty or consists entirely of |
14 | | // 255's, we just return the empty string. |
15 | 5.94k | while (!prefix->empty()) { |
16 | 5.30k | char& c = prefix->back(); |
17 | 5.30k | if (c == '\xff') { // char literal avoids signed/unsigned. |
18 | 2.83k | prefix->pop_back(); |
19 | 2.83k | } else { |
20 | 2.46k | ++c; |
21 | 2.46k | break; |
22 | 2.46k | } |
23 | 5.30k | } |
24 | 3.10k | } |
25 | | |
26 | | } // namespace re2 |