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
57 namespace benchmark {
58
59 // A wrapper around the POSIX regular expression API that provides automatic
60 // cleanup
61 class Regex {
62 public:
Regex()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
Init(const std::string & spec,std::string * error)90 inline 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 }
100 catch (const std::regex_error& e) {
101 if (error) {
102 *error = e.what();
103 }
104 }
105 #endif
106 return init_;
107 }
108
~Regex()109 inline Regex::~Regex() {}
110
Match(const std::string & str)111 inline 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
Init(const std::string & spec,std::string * error)119 inline 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
~Regex()142 inline Regex::~Regex() {
143 if (init_) {
144 regfree(&re_);
145 }
146 }
147
Match(const std::string & str)148 inline 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