1// Copyright 2015 Google Inc. All rights reserved.
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7// http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15#ifndef BENCHMARK_RE_H_
16#define BENCHMARK_RE_H_
17
18#if defined(HAVE_STD_REGEX)
19#include <regex>
20#elif defined(HAVE_GNU_POSIX_REGEX)
21#include <gnuregex.h>
22#elif defined(HAVE_POSIX_REGEX)
23#include <regex.h>
24#else
25#error No regular expression backend was found!
26#endif
27#include <string>
28
29#include "check.h"
30
31namespace benchmark {
32
33// A wrapper around the POSIX regular expression API that provides automatic
34// cleanup
35class Regex {
36 public:
37 Regex() : init_(false) {}
38
39 ~Regex();
40
41 // Compile a regular expression matcher from spec. Returns true on success.
42 //
43 // On failure (and if error is not nullptr), error is populated with a human
44 // readable error message if an error occurs.
45 bool Init(const std::string& spec, std::string* error);
46
47 // Returns whether str matches the compiled regular expression.
48 bool Match(const std::string& str);
49
50 private:
51 bool init_;
52// Underlying regular expression object
53#if defined(HAVE_STD_REGEX)
54 std::regex re_;
55#elif defined(HAVE_POSIX_REGEX) || defined(HAVE_GNU_POSIX_REGEX)
56 regex_t re_;
57#else
58#error No regular expression backend implementation available
59#endif
60};
61
62#if defined(HAVE_STD_REGEX)
63
64inline bool Regex::Init(const std::string& spec, std::string* error) {
65 try {
66 re_ = std::regex(spec, std::regex_constants::extended);
67
68 init_ = true;
69 } catch (const std::regex_error& e) {
70 if (error) {
71 *error = e.what();
72 }
73 }
74 return init_;
75}
76
77inline Regex::~Regex() {}
78
79inline bool Regex::Match(const std::string& str) {
80 if (!init_) {
81 return false;
82 }
83 return std::regex_search(str, re_);
84}
85
86#else
87inline bool Regex::Init(const std::string& spec, std::string* error) {
88 int ec = regcomp(&re_, spec.c_str(), REG_EXTENDED | REG_NOSUB);
89 if (ec != 0) {
90 if (error) {
91 size_t needed = regerror(ec, &re_, nullptr, 0);
92 char* errbuf = new char[needed];
93 regerror(ec, &re_, errbuf, needed);
94
95 // regerror returns the number of bytes necessary to null terminate
96 // the string, so we move that when assigning to error.
97 CHECK_NE(needed, 0);
98 error->assign(errbuf, needed - 1);
99
100 delete[] errbuf;
101 }
102
103 return false;
104 }
105
106 init_ = true;
107 return true;
108}
109
110inline Regex::~Regex() {
111 if (init_) {
112 regfree(&re_);
113 }
114}
115
116inline bool Regex::Match(const std::string& str) {
117 if (!init_) {
118 return false;
119 }
120 return regexec(&re_, str.c_str(), 0, nullptr, 0) == 0;
121}
122#endif
123
124} // end namespace benchmark
125
126#endif // BENCHMARK_RE_H_
127