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#include "internal_macros.h"
19
20// clang-format off
21
22#if !defined(HAVE_STD_REGEX) && \
23 !defined(HAVE_GNU_POSIX_REGEX) && \
24 !defined(HAVE_POSIX_REGEX)
25 // No explicit regex selection; detect based on builtin hints.
26 #if defined(BENCHMARK_OS_LINUX) || defined(BENCHMARK_OS_APPLE)
27 #define HAVE_POSIX_REGEX 1
28 #elif __cplusplus >= 199711L
29 #define HAVE_STD_REGEX 1
30 #endif
31#endif
32
33// Prefer C regex libraries when compiling w/o exceptions so that we can
34// correctly report errors.
35#if defined(BENCHMARK_HAS_NO_EXCEPTIONS) && \
36 defined(BENCHMARK_HAVE_STD_REGEX) && \
37 (defined(HAVE_GNU_POSIX_REGEX) || defined(HAVE_POSIX_REGEX))
38 #undef HAVE_STD_REGEX
39#endif
40
41#if defined(HAVE_STD_REGEX)
42 #include <regex>
43#elif defined(HAVE_GNU_POSIX_REGEX)
44 #include <gnuregex.h>
45#elif defined(HAVE_POSIX_REGEX)
46 #include <regex.h>
47#else
48#error No regular expression backend was found!
49#endif
50
51// clang-format on
52
53#include <string>
54
55#include "check.h"
56
57namespace benchmark {
58
59// A wrapper around the POSIX regular expression API that provides automatic
60// cleanup
61class Regex {
62 public:
63 Regex() : init_(false) {}
64
65 ~Regex();
66
67 // Compile a regular expression matcher from spec. Returns true on success.
68 //
69 // On failure (and if error is not nullptr), error is populated with a human
70 // readable error message if an error occurs.
71 bool Init(const std::string& spec, std::string* error);
72
73 // Returns whether str matches the compiled regular expression.
74 bool Match(const std::string& str);
75
76 private:
77 bool init_;
78// Underlying regular expression object
79#if defined(HAVE_STD_REGEX)
80 std::regex re_;
81#elif defined(HAVE_POSIX_REGEX) || defined(HAVE_GNU_POSIX_REGEX)
82 regex_t re_;
83#else
84#error No regular expression backend implementation available
85#endif
86};
87
88#if defined(HAVE_STD_REGEX)
89
90inline bool Regex::Init(const std::string& spec, std::string* error) {
91#ifdef BENCHMARK_HAS_NO_EXCEPTIONS
92 ((void)error); // suppress unused warning
93#else
94 try {
95#endif
96 re_ = std::regex(spec, std::regex_constants::extended);
97 init_ = true;
98#ifndef BENCHMARK_HAS_NO_EXCEPTIONS
99}
100catch (const std::regex_error& e) {
101 if (error) {
102 *error = e.what();
103 }
104}
105#endif
106return init_;
107}
108
109inline Regex::~Regex() {}
110
111inline bool Regex::Match(const std::string& str) {
112 if (!init_) {
113 return false;
114 }
115 return std::regex_search(str, re_);
116}
117
118#else
119inline bool Regex::Init(const std::string& spec, std::string* error) {
120 int ec = regcomp(&re_, spec.c_str(), REG_EXTENDED | REG_NOSUB);
121 if (ec != 0) {
122 if (error) {
123 size_t needed = regerror(ec, &re_, nullptr, 0);
124 char* errbuf = new char[needed];
125 regerror(ec, &re_, errbuf, needed);
126
127 // regerror returns the number of bytes necessary to null terminate
128 // the string, so we move that when assigning to error.
129 BM_CHECK_NE(needed, 0);
130 error->assign(errbuf, needed - 1);
131
132 delete[] errbuf;
133 }
134
135 return false;
136 }
137
138 init_ = true;
139 return true;
140}
141
142inline Regex::~Regex() {
143 if (init_) {
144 regfree(&re_);
145 }
146}
147
148inline bool Regex::Match(const std::string& str) {
149 if (!init_) {
150 return false;
151 }
152 return regexec(&re_, str.c_str(), 0, nullptr, 0) == 0;
153}
154#endif
155
156} // end namespace benchmark
157
158#endif // BENCHMARK_RE_H_
159