blob: da06f85a335908e780749b0c20d61faadf7348d4 (
plain) (
blame)
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
|
// Copyright 1999-2005 The RE2 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 "util/strutil.h"
namespace re2 {
void PrefixSuccessor(std::string* prefix) {
// We can increment the last character in the string and be done
// unless that character is 255, in which case we have to erase the
// last character and increment the previous character, unless that
// is 255, etc. If the string is empty or consists entirely of
// 255's, we just return the empty string.
while (!prefix->empty()) {
char& c = prefix->back();
if (c == '\xff') { // char literal avoids signed/unsigned.
prefix->pop_back();
} else {
++c;
break;
}
}
}
} // namespace re2
|
