Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 1 | //===----------------------------------------------------------------------===// |
| 2 | // |
Howard Hinnant | f5256e1 | 2010-05-11 21:36:01 +0000 | [diff] [blame] | 3 | // The LLVM Compiler Infrastructure |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 4 | // |
Howard Hinnant | b64f8b0 | 2010-11-16 22:09:02 +0000 | [diff] [blame] | 5 | // This file is dual licensed under the MIT and the University of Illinois Open |
| 6 | // Source Licenses. See LICENSE.TXT for details. |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 7 | // |
| 8 | //===----------------------------------------------------------------------===// |
Jonathan Roelofs | 8d86b2e | 2014-09-05 19:45:05 +0000 | [diff] [blame] | 9 | // |
| 10 | // UNSUPPORTED: libcpp-has-no-threads |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 11 | |
| 12 | // <mutex> |
| 13 | |
| 14 | // struct once_flag; |
| 15 | |
| 16 | // template<class Callable, class ...Args> |
Eric Fiselier | bc1e44d | 2015-06-13 02:23:00 +0000 | [diff] [blame] | 17 | // void call_once(once_flag& flag, Callable&& func, Args&&... args); |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 18 | |
| 19 | #include <mutex> |
| 20 | #include <thread> |
| 21 | #include <cassert> |
| 22 | |
| 23 | typedef std::chrono::milliseconds ms; |
| 24 | |
| 25 | std::once_flag flg0; |
| 26 | |
| 27 | int init0_called = 0; |
| 28 | |
| 29 | void init0() |
| 30 | { |
| 31 | std::this_thread::sleep_for(ms(250)); |
| 32 | ++init0_called; |
| 33 | } |
| 34 | |
| 35 | void f0() |
| 36 | { |
| 37 | std::call_once(flg0, init0); |
| 38 | } |
| 39 | |
| 40 | std::once_flag flg3; |
| 41 | |
| 42 | int init3_called = 0; |
| 43 | int init3_completed = 0; |
| 44 | |
| 45 | void init3() |
| 46 | { |
| 47 | ++init3_called; |
| 48 | std::this_thread::sleep_for(ms(250)); |
| 49 | if (init3_called == 1) |
| 50 | throw 1; |
| 51 | ++init3_completed; |
| 52 | } |
| 53 | |
| 54 | void f3() |
| 55 | { |
| 56 | try |
| 57 | { |
| 58 | std::call_once(flg3, init3); |
| 59 | } |
| 60 | catch (...) |
| 61 | { |
| 62 | } |
| 63 | } |
| 64 | |
| 65 | #ifndef _LIBCPP_HAS_NO_VARIADICS |
| 66 | |
| 67 | struct init1 |
| 68 | { |
| 69 | static int called; |
| 70 | |
| 71 | void operator()(int i) {called += i;} |
| 72 | }; |
| 73 | |
| 74 | int init1::called = 0; |
| 75 | |
| 76 | std::once_flag flg1; |
| 77 | |
| 78 | void f1() |
| 79 | { |
| 80 | std::call_once(flg1, init1(), 1); |
| 81 | } |
| 82 | |
| 83 | struct init2 |
| 84 | { |
| 85 | static int called; |
| 86 | |
| 87 | void operator()(int i, int j) const {called += i + j;} |
| 88 | }; |
| 89 | |
| 90 | int init2::called = 0; |
| 91 | |
| 92 | std::once_flag flg2; |
| 93 | |
| 94 | void f2() |
| 95 | { |
| 96 | std::call_once(flg2, init2(), 2, 3); |
| 97 | std::call_once(flg2, init2(), 4, 5); |
| 98 | } |
| 99 | |
Howard Hinnant | f11ea14 | 2010-08-22 00:50:25 +0000 | [diff] [blame] | 100 | #endif // _LIBCPP_HAS_NO_VARIADICS |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 101 | |
| 102 | std::once_flag flg41; |
| 103 | std::once_flag flg42; |
| 104 | |
| 105 | int init41_called = 0; |
| 106 | int init42_called = 0; |
| 107 | |
| 108 | void init42(); |
| 109 | |
| 110 | void init41() |
| 111 | { |
| 112 | std::this_thread::sleep_for(ms(250)); |
| 113 | ++init41_called; |
| 114 | } |
| 115 | |
| 116 | void init42() |
| 117 | { |
| 118 | std::this_thread::sleep_for(ms(250)); |
| 119 | ++init42_called; |
| 120 | } |
| 121 | |
| 122 | void f41() |
| 123 | { |
| 124 | std::call_once(flg41, init41); |
| 125 | std::call_once(flg42, init42); |
| 126 | } |
| 127 | |
| 128 | void f42() |
| 129 | { |
| 130 | std::call_once(flg42, init42); |
| 131 | std::call_once(flg41, init41); |
| 132 | } |
| 133 | |
Howard Hinnant | ad935d5 | 2011-05-16 19:05:11 +0000 | [diff] [blame] | 134 | #ifndef _LIBCPP_HAS_NO_VARIADICS |
| 135 | |
| 136 | class MoveOnly |
| 137 | { |
Jonathan Roelofs | 8d86b2e | 2014-09-05 19:45:05 +0000 | [diff] [blame] | 138 | #if !defined(__clang__) |
| 139 | // GCC 4.8 complains about the following being private |
| 140 | public: |
| 141 | MoveOnly(const MoveOnly&) |
| 142 | { |
| 143 | } |
| 144 | #else |
Howard Hinnant | ad935d5 | 2011-05-16 19:05:11 +0000 | [diff] [blame] | 145 | MoveOnly(const MoveOnly&); |
Jonathan Roelofs | 8d86b2e | 2014-09-05 19:45:05 +0000 | [diff] [blame] | 146 | #endif |
Howard Hinnant | ad935d5 | 2011-05-16 19:05:11 +0000 | [diff] [blame] | 147 | public: |
| 148 | MoveOnly() {} |
| 149 | MoveOnly(MoveOnly&&) {} |
| 150 | |
| 151 | void operator()(MoveOnly&&) |
| 152 | { |
| 153 | } |
| 154 | }; |
| 155 | |
Eric Fiselier | bc1e44d | 2015-06-13 02:23:00 +0000 | [diff] [blame] | 156 | class NonCopyable |
| 157 | { |
| 158 | #if !defined(__clang__) |
| 159 | // GCC 4.8 complains about the following being private |
| 160 | public: |
| 161 | NonCopyable(const NonCopyable&) |
| 162 | { |
| 163 | } |
| 164 | #else |
| 165 | NonCopyable(const NonCopyable&); |
| 166 | #endif |
| 167 | public: |
| 168 | NonCopyable() {} |
| 169 | |
| 170 | void operator()(int&) {} |
| 171 | }; |
| 172 | |
| 173 | #if __cplusplus >= 201103L |
| 174 | // reference qualifiers on functions are a C++11 extension |
| 175 | struct RefQual |
| 176 | { |
| 177 | int lv_called, rv_called; |
| 178 | |
| 179 | RefQual() : lv_called(0), rv_called(0) {} |
| 180 | |
| 181 | void operator()() & { ++lv_called; } |
| 182 | void operator()() && { ++rv_called; } |
| 183 | }; |
| 184 | #endif |
Howard Hinnant | ad935d5 | 2011-05-16 19:05:11 +0000 | [diff] [blame] | 185 | #endif |
| 186 | |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 187 | int main() |
| 188 | { |
| 189 | // check basic functionality |
| 190 | { |
| 191 | std::thread t0(f0); |
| 192 | std::thread t1(f0); |
| 193 | t0.join(); |
| 194 | t1.join(); |
| 195 | assert(init0_called == 1); |
| 196 | } |
| 197 | // check basic exception safety |
| 198 | { |
| 199 | std::thread t0(f3); |
| 200 | std::thread t1(f3); |
| 201 | t0.join(); |
| 202 | t1.join(); |
| 203 | assert(init3_called == 2); |
| 204 | assert(init3_completed == 1); |
| 205 | } |
| 206 | // check deadlock avoidance |
| 207 | { |
| 208 | std::thread t0(f41); |
| 209 | std::thread t1(f42); |
| 210 | t0.join(); |
| 211 | t1.join(); |
| 212 | assert(init41_called == 1); |
| 213 | assert(init42_called == 1); |
| 214 | } |
| 215 | #ifndef _LIBCPP_HAS_NO_VARIADICS |
| 216 | // check functors with 1 arg |
| 217 | { |
| 218 | std::thread t0(f1); |
| 219 | std::thread t1(f1); |
| 220 | t0.join(); |
| 221 | t1.join(); |
| 222 | assert(init1::called == 1); |
| 223 | } |
| 224 | // check functors with 2 args |
| 225 | { |
| 226 | std::thread t0(f2); |
| 227 | std::thread t1(f2); |
| 228 | t0.join(); |
| 229 | t1.join(); |
| 230 | assert(init2::called == 5); |
| 231 | } |
Howard Hinnant | ad935d5 | 2011-05-16 19:05:11 +0000 | [diff] [blame] | 232 | { |
| 233 | std::once_flag f; |
| 234 | std::call_once(f, MoveOnly(), MoveOnly()); |
| 235 | } |
Eric Fiselier | bc1e44d | 2015-06-13 02:23:00 +0000 | [diff] [blame] | 236 | // check LWG2442: call_once() shouldn't DECAY_COPY() |
| 237 | { |
| 238 | std::once_flag f; |
| 239 | int i = 0; |
| 240 | std::call_once(f, NonCopyable(), i); |
| 241 | } |
| 242 | #if __cplusplus >= 201103L |
| 243 | // reference qualifiers on functions are a C++11 extension |
| 244 | { |
| 245 | std::once_flag f1, f2; |
| 246 | RefQual rq; |
| 247 | std::call_once(f1, rq); |
| 248 | assert(rq.lv_called == 1); |
| 249 | std::call_once(f2, std::move(rq)); |
| 250 | assert(rq.rv_called == 1); |
| 251 | } |
| 252 | #endif |
Howard Hinnant | f11ea14 | 2010-08-22 00:50:25 +0000 | [diff] [blame] | 253 | #endif // _LIBCPP_HAS_NO_VARIADICS |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 254 | } |