| 1 | // Copyright 2023 Peter Dimov. |
| 2 | // Copyright 2023 Christian Mazakas. |
| 3 | // Copyright 2023 Ed Catmur |
| 4 | // Distributed under the Boost Software License, Version 1.0. |
| 5 | // https://www.boost.org/LICENSE_1_0.txt |
| 6 | |
| 7 | #ifdef _MSC_VER |
| 8 | #pragma warning(disable: 4530) // C++ exception handler used, but unwing semantics not enabled |
| 9 | #pragma warning(disable: 4577) // noexcept used with no exception handling mode specified |
| 10 | #endif |
| 11 | |
| 12 | #include <boost/compat/shared_lock.hpp> |
| 13 | |
| 14 | #include <boost/core/lightweight_test.hpp> |
| 15 | #include <boost/core/lightweight_test_trait.hpp> |
| 16 | #include <boost/throw_exception.hpp> |
| 17 | #include <boost/config.hpp> |
| 18 | |
| 19 | #include <atomic> |
| 20 | #include <memory> |
| 21 | #include <mutex> |
| 22 | #include <thread> |
| 23 | #include <type_traits> |
| 24 | #include <stdexcept> |
| 25 | #include <cstdio> |
| 26 | |
| 27 | #define STATIC_ASSERT( ... ) static_assert( __VA_ARGS__, #__VA_ARGS__ ) |
| 28 | |
| 29 | #ifdef __clang__ |
| 30 | #pragma clang diagnostic ignored "-Wself-move" |
| 31 | #endif |
| 32 | #if defined(__GNUC__) && __GNUC__ >= 13 |
| 33 | #pragma GCC diagnostic ignored "-Wself-move" |
| 34 | #endif |
| 35 | |
| 36 | struct invalid_lock_use: public std::runtime_error |
| 37 | { |
| 38 | invalid_lock_use(): std::runtime_error( "Invalid lock use" ) |
| 39 | { |
| 40 | } |
| 41 | }; |
| 42 | |
| 43 | struct dummy_lock { |
| 44 | private: |
| 45 | int lock_shared_count_ = 0; |
| 46 | int unlock_shared_count_ = 0; |
| 47 | |
| 48 | int lock_unique_count_ = 0; |
| 49 | int unlock_unique_count_ = 0; |
| 50 | |
| 51 | public: |
| 52 | dummy_lock() = default; |
| 53 | ~dummy_lock() { |
| 54 | BOOST_TEST_EQ( lock_shared_count_, unlock_shared_count_ ); |
| 55 | BOOST_TEST_EQ( lock_unique_count_, unlock_unique_count_ ); |
| 56 | } |
| 57 | |
| 58 | void lock() { |
| 59 | if ( lock_shared_count_ != unlock_shared_count_ ) { |
| 60 | boost::throw_exception( e: invalid_lock_use(), BOOST_CURRENT_LOCATION ); |
| 61 | } |
| 62 | ++lock_unique_count_; |
| 63 | } |
| 64 | |
| 65 | void unlock() { ++unlock_unique_count_; } |
| 66 | |
| 67 | bool try_lock() { |
| 68 | if ( lock_shared_count_ != unlock_shared_count_ ) { |
| 69 | return false; |
| 70 | } |
| 71 | |
| 72 | ++lock_unique_count_; |
| 73 | return true; |
| 74 | } |
| 75 | |
| 76 | void lock_shared() { |
| 77 | if ( lock_unique_count_ != unlock_unique_count_ ) { |
| 78 | boost::throw_exception( e: invalid_lock_use(), BOOST_CURRENT_LOCATION ); |
| 79 | } |
| 80 | ++lock_shared_count_; |
| 81 | } |
| 82 | |
| 83 | bool try_lock_shared() { |
| 84 | if ( lock_unique_count_ != unlock_unique_count_ ) { |
| 85 | return false; |
| 86 | } |
| 87 | ++lock_shared_count_; |
| 88 | return true; |
| 89 | } |
| 90 | |
| 91 | void unlock_shared() { ++unlock_shared_count_; } |
| 92 | |
| 93 | int shared_lock_count() const noexcept { return lock_shared_count_; } |
| 94 | }; |
| 95 | |
| 96 | namespace { |
| 97 | |
| 98 | using shared_lock_type = boost::compat::shared_lock<dummy_lock>; |
| 99 | |
| 100 | // verify that our dummy_lock throws when we hope it does |
| 101 | void sanity_tests() { |
| 102 | dummy_lock sp; |
| 103 | sp.lock(); |
| 104 | BOOST_TEST_THROWS( sp.lock_shared(), invalid_lock_use ); |
| 105 | sp.unlock(); |
| 106 | |
| 107 | sp.lock_shared(); |
| 108 | BOOST_TEST_THROWS( sp.lock(), invalid_lock_use ); |
| 109 | sp.unlock_shared(); |
| 110 | } |
| 111 | |
| 112 | void default_constructor() { |
| 113 | // shared_lock() noexcept; |
| 114 | |
| 115 | BOOST_TEST_TRAIT_SAME( typename shared_lock_type::mutex_type, dummy_lock ); |
| 116 | BOOST_TEST_TRAIT_TRUE( |
| 117 | (std::is_nothrow_default_constructible<shared_lock_type>)); |
| 118 | |
| 119 | shared_lock_type lock; |
| 120 | BOOST_TEST_EQ( lock.mutex(), nullptr ); |
| 121 | BOOST_TEST( !lock.owns_lock() ); |
| 122 | BOOST_TEST( !lock ); |
| 123 | } |
| 124 | |
| 125 | void locking_construtor() { |
| 126 | // explicit shared_lock( mutex_type& m ); |
| 127 | |
| 128 | dummy_lock sp; |
| 129 | |
| 130 | { |
| 131 | shared_lock_type lock( sp ); |
| 132 | BOOST_TEST_EQ( lock.mutex(), std::addressof( sp ) ); |
| 133 | BOOST_TEST( lock.owns_lock() ); |
| 134 | BOOST_TEST( lock ); |
| 135 | BOOST_TEST_EQ( sp.shared_lock_count(), 1 ); |
| 136 | } |
| 137 | } |
| 138 | |
| 139 | void deferred_constructor() { |
| 140 | // shared_lock( mutex_type& m, defer_lock_t t ) noexcept; |
| 141 | |
| 142 | dummy_lock sp; |
| 143 | |
| 144 | shared_lock_type lock( sp, std::defer_lock ); |
| 145 | |
| 146 | BOOST_TEST_EQ( lock.mutex(), std::addressof( sp ) ); |
| 147 | BOOST_TEST( !lock.owns_lock() ); |
| 148 | BOOST_TEST( !lock ); |
| 149 | BOOST_TEST_EQ( sp.shared_lock_count(), 0 ); |
| 150 | } |
| 151 | |
| 152 | void try_lock_constructor() { |
| 153 | // shared_lock( mutex_type& m, try_to_lock_t t ); |
| 154 | |
| 155 | dummy_lock sp; |
| 156 | |
| 157 | { |
| 158 | shared_lock_type lock( sp, std::try_to_lock ); |
| 159 | BOOST_TEST_EQ( lock.mutex(), std::addressof( sp ) ); |
| 160 | BOOST_TEST( lock.owns_lock() ); |
| 161 | BOOST_TEST( lock ); |
| 162 | BOOST_TEST_EQ( sp.shared_lock_count(), 1 ); |
| 163 | } |
| 164 | |
| 165 | { |
| 166 | sp.lock(); |
| 167 | |
| 168 | shared_lock_type lock( sp, std::try_to_lock ); |
| 169 | BOOST_TEST_EQ( lock.mutex(), std::addressof( sp ) ); |
| 170 | BOOST_TEST( !lock.owns_lock() ); |
| 171 | BOOST_TEST( !lock ); |
| 172 | BOOST_TEST_EQ( sp.shared_lock_count(), 1 ); |
| 173 | |
| 174 | sp.unlock(); |
| 175 | } |
| 176 | } |
| 177 | |
| 178 | void adopt_lock_constructor() { |
| 179 | // shared_lock(mutex_type& m, adopt_lock_t); |
| 180 | |
| 181 | dummy_lock sp; |
| 182 | sp.lock_shared(); |
| 183 | |
| 184 | { |
| 185 | shared_lock_type lock( sp, std::adopt_lock ); |
| 186 | BOOST_TEST_EQ( lock.mutex(), std::addressof( sp ) ); |
| 187 | BOOST_TEST( lock.owns_lock() ); |
| 188 | BOOST_TEST( lock ); |
| 189 | BOOST_TEST_EQ( sp.shared_lock_count(), 1 ); |
| 190 | } |
| 191 | |
| 192 | sp.lock(); |
| 193 | sp.unlock(); |
| 194 | } |
| 195 | |
| 196 | void move_constructor() { |
| 197 | BOOST_TEST_TRAIT_TRUE( |
| 198 | (std::is_nothrow_move_constructible<shared_lock_type>)); |
| 199 | |
| 200 | { |
| 201 | dummy_lock sp; |
| 202 | |
| 203 | shared_lock_type lock( sp ); |
| 204 | shared_lock_type lock2( std::move( lock ) ); |
| 205 | BOOST_TEST_EQ( lock2.mutex(), std::addressof( sp ) ); |
| 206 | BOOST_TEST( lock2.owns_lock() ); |
| 207 | BOOST_TEST( lock2 ); |
| 208 | |
| 209 | BOOST_TEST_EQ( lock.mutex(), nullptr ); |
| 210 | BOOST_TEST( !lock.owns_lock() ); |
| 211 | BOOST_TEST( !lock ); |
| 212 | |
| 213 | BOOST_TEST_EQ( sp.shared_lock_count(), 1 ); |
| 214 | } |
| 215 | |
| 216 | { |
| 217 | dummy_lock sp; |
| 218 | |
| 219 | shared_lock_type lock( sp, std::defer_lock ); |
| 220 | shared_lock_type lock2( std::move( lock ) ); |
| 221 | BOOST_TEST_EQ( lock2.mutex(), std::addressof( sp ) ); |
| 222 | BOOST_TEST( !lock2.owns_lock() ); |
| 223 | BOOST_TEST( !lock2 ); |
| 224 | |
| 225 | BOOST_TEST_EQ( lock.mutex(), nullptr ); |
| 226 | BOOST_TEST( !lock.owns_lock() ); |
| 227 | BOOST_TEST( !lock ); |
| 228 | |
| 229 | BOOST_TEST_EQ( sp.shared_lock_count(), 0 ); |
| 230 | } |
| 231 | |
| 232 | { |
| 233 | dummy_lock sp; |
| 234 | |
| 235 | shared_lock_type lock; |
| 236 | shared_lock_type lock2( std::move( lock ) ); |
| 237 | BOOST_TEST_EQ( lock2.mutex(), nullptr ); |
| 238 | BOOST_TEST( !lock2.owns_lock() ); |
| 239 | BOOST_TEST( !lock2 ); |
| 240 | |
| 241 | BOOST_TEST_EQ( lock.mutex(), nullptr ); |
| 242 | BOOST_TEST( !lock.owns_lock() ); |
| 243 | BOOST_TEST( !lock ); |
| 244 | |
| 245 | BOOST_TEST_EQ( sp.shared_lock_count(), 0 ); |
| 246 | } |
| 247 | } |
| 248 | |
| 249 | void move_assignment() { |
| 250 | BOOST_TEST_TRAIT_TRUE( (std::is_nothrow_move_assignable<shared_lock_type>)); |
| 251 | |
| 252 | { |
| 253 | // lhs not bound, not locked |
| 254 | // rhs not bound, not locked |
| 255 | dummy_lock sp, sp2; |
| 256 | |
| 257 | shared_lock_type lock; |
| 258 | shared_lock_type lock2; |
| 259 | |
| 260 | lock2 = std::move( lock ); |
| 261 | BOOST_TEST_EQ( lock2.mutex(), nullptr ); |
| 262 | BOOST_TEST( !lock2.owns_lock() ); |
| 263 | BOOST_TEST( !lock2 ); |
| 264 | |
| 265 | BOOST_TEST_EQ( lock.mutex(), nullptr ); |
| 266 | BOOST_TEST( !lock.owns_lock() ); |
| 267 | BOOST_TEST( !lock ); |
| 268 | |
| 269 | BOOST_TEST_EQ( sp.shared_lock_count(), 0 ); |
| 270 | BOOST_TEST_EQ( sp2.shared_lock_count(), 0 ); |
| 271 | } |
| 272 | |
| 273 | { |
| 274 | // lhs not bound, not locked |
| 275 | // rhs bound, locked |
| 276 | dummy_lock sp; |
| 277 | |
| 278 | shared_lock_type lock( sp ); |
| 279 | shared_lock_type lock2; |
| 280 | |
| 281 | lock2 = std::move( lock ); |
| 282 | BOOST_TEST_EQ( lock2.mutex(), std::addressof( sp ) ); |
| 283 | BOOST_TEST( lock2.owns_lock() ); |
| 284 | BOOST_TEST( lock2 ); |
| 285 | |
| 286 | BOOST_TEST_EQ( lock.mutex(), nullptr ); |
| 287 | BOOST_TEST( !lock.owns_lock() ); |
| 288 | BOOST_TEST( !lock ); |
| 289 | |
| 290 | BOOST_TEST_EQ( sp.shared_lock_count(), 1 ); |
| 291 | } |
| 292 | |
| 293 | { |
| 294 | // lhs not bound, not locked |
| 295 | // rhs bound, not locked |
| 296 | dummy_lock sp, sp2; |
| 297 | |
| 298 | shared_lock_type lock( sp, std::defer_lock ); |
| 299 | shared_lock_type lock2; |
| 300 | |
| 301 | lock2 = std::move( lock ); |
| 302 | BOOST_TEST_EQ( lock2.mutex(), std::addressof( sp ) ); |
| 303 | BOOST_TEST( !lock2.owns_lock() ); |
| 304 | BOOST_TEST( !lock2 ); |
| 305 | |
| 306 | BOOST_TEST_EQ( lock.mutex(), nullptr ); |
| 307 | BOOST_TEST( !lock.owns_lock() ); |
| 308 | BOOST_TEST( !lock ); |
| 309 | |
| 310 | BOOST_TEST_EQ( sp.shared_lock_count(), 0 ); |
| 311 | BOOST_TEST_EQ( sp2.shared_lock_count(), 0 ); |
| 312 | } |
| 313 | |
| 314 | { |
| 315 | // lhs bound, locked |
| 316 | // rhs not bound, not locked |
| 317 | |
| 318 | dummy_lock sp, sp2; |
| 319 | |
| 320 | shared_lock_type lock; |
| 321 | shared_lock_type lock2( sp2 ); |
| 322 | |
| 323 | lock2 = std::move( lock ); |
| 324 | |
| 325 | BOOST_TEST_EQ( lock2.mutex(), nullptr ); |
| 326 | BOOST_TEST( !lock2.owns_lock() ); |
| 327 | BOOST_TEST( !lock2 ); |
| 328 | |
| 329 | BOOST_TEST_EQ( lock.mutex(), nullptr ); |
| 330 | BOOST_TEST( !lock.owns_lock() ); |
| 331 | BOOST_TEST( !lock ); |
| 332 | |
| 333 | BOOST_TEST_EQ( sp.shared_lock_count(), 0 ); |
| 334 | BOOST_TEST_EQ( sp2.shared_lock_count(), 1 ); |
| 335 | } |
| 336 | |
| 337 | { |
| 338 | // lhs bound, not locked |
| 339 | // rhs not bound, not locked |
| 340 | |
| 341 | dummy_lock sp, sp2; |
| 342 | |
| 343 | shared_lock_type lock; |
| 344 | shared_lock_type lock2( sp, std::defer_lock ); |
| 345 | |
| 346 | lock2 = std::move( lock ); |
| 347 | |
| 348 | BOOST_TEST_EQ( lock2.mutex(), nullptr ); |
| 349 | BOOST_TEST( !lock2.owns_lock() ); |
| 350 | BOOST_TEST( !lock2 ); |
| 351 | |
| 352 | BOOST_TEST_EQ( lock.mutex(), nullptr ); |
| 353 | BOOST_TEST( !lock.owns_lock() ); |
| 354 | |
| 355 | BOOST_TEST_EQ( sp.shared_lock_count(), 0 ); |
| 356 | BOOST_TEST_EQ( sp2.shared_lock_count(), 0 ); |
| 357 | } |
| 358 | |
| 359 | { |
| 360 | // lhs bound, locked |
| 361 | // rhs bound, locked |
| 362 | |
| 363 | dummy_lock sp, sp2; |
| 364 | |
| 365 | shared_lock_type lock( sp ); |
| 366 | shared_lock_type lock2( sp2 ); |
| 367 | |
| 368 | lock2 = std::move( lock ); |
| 369 | BOOST_TEST_EQ( lock2.mutex(), std::addressof( sp ) ); |
| 370 | BOOST_TEST( lock2.owns_lock() ); |
| 371 | BOOST_TEST( lock2 ); |
| 372 | |
| 373 | BOOST_TEST_EQ( lock.mutex(), nullptr ); |
| 374 | BOOST_TEST( !lock.owns_lock() ); |
| 375 | BOOST_TEST( !lock ); |
| 376 | |
| 377 | BOOST_TEST_EQ( sp.shared_lock_count(), 1 ); |
| 378 | BOOST_TEST_EQ( sp2.shared_lock_count(), 1 ); |
| 379 | } |
| 380 | |
| 381 | { |
| 382 | // self-assign, locked |
| 383 | |
| 384 | dummy_lock sp; |
| 385 | shared_lock_type lock( sp ); |
| 386 | |
| 387 | lock = std::move( lock ); |
| 388 | BOOST_TEST_EQ( lock.mutex(), std::addressof( sp ) ); |
| 389 | BOOST_TEST( lock.owns_lock() ); |
| 390 | BOOST_TEST( lock ); |
| 391 | |
| 392 | BOOST_TEST_EQ( sp.shared_lock_count(), 1 ); |
| 393 | } |
| 394 | } |
| 395 | |
| 396 | void lock() { |
| 397 | { |
| 398 | dummy_lock sp; |
| 399 | shared_lock_type lock( sp, std::defer_lock ); |
| 400 | |
| 401 | lock.lock(); |
| 402 | BOOST_TEST( lock.owns_lock() ); |
| 403 | BOOST_TEST( lock ); |
| 404 | BOOST_TEST_THROWS( lock.lock(), std::system_error ); |
| 405 | |
| 406 | BOOST_TEST_EQ( sp.shared_lock_count(), 1 ); |
| 407 | } |
| 408 | |
| 409 | { |
| 410 | dummy_lock sp; |
| 411 | shared_lock_type lock; |
| 412 | BOOST_TEST_THROWS( lock.lock(), std::system_error ); |
| 413 | BOOST_TEST_EQ( sp.shared_lock_count(), 0 ); |
| 414 | } |
| 415 | } |
| 416 | |
| 417 | void unlock() { |
| 418 | dummy_lock sp; |
| 419 | |
| 420 | shared_lock_type lock( sp ); |
| 421 | lock.unlock(); |
| 422 | |
| 423 | BOOST_TEST( !lock.owns_lock() ); |
| 424 | BOOST_TEST( !lock ); |
| 425 | |
| 426 | BOOST_TEST_EQ( sp.shared_lock_count(), 1 ); |
| 427 | |
| 428 | sp.lock(); |
| 429 | sp.unlock(); |
| 430 | |
| 431 | BOOST_TEST_THROWS( lock.unlock(), std::system_error ); |
| 432 | } |
| 433 | |
| 434 | void try_lock() { |
| 435 | dummy_lock sp; |
| 436 | |
| 437 | { |
| 438 | shared_lock_type lock( sp, std::defer_lock ); |
| 439 | BOOST_TEST( lock.try_lock() ); |
| 440 | BOOST_TEST( lock.owns_lock() ); |
| 441 | BOOST_TEST( lock ); |
| 442 | |
| 443 | BOOST_TEST( !sp.try_lock() ); |
| 444 | |
| 445 | BOOST_TEST_THROWS( lock.try_lock(), std::system_error ); |
| 446 | |
| 447 | lock.unlock(); |
| 448 | |
| 449 | sp.lock(); |
| 450 | |
| 451 | BOOST_TEST( !lock.try_lock() ); |
| 452 | BOOST_TEST( !lock.owns_lock() ); |
| 453 | BOOST_TEST( !lock ); |
| 454 | |
| 455 | sp.unlock(); |
| 456 | } |
| 457 | |
| 458 | { |
| 459 | shared_lock_type lock; |
| 460 | BOOST_TEST_THROWS( lock.try_lock(), std::system_error ); |
| 461 | } |
| 462 | } |
| 463 | |
| 464 | void swap() { |
| 465 | dummy_lock sp, sp2; |
| 466 | |
| 467 | { |
| 468 | shared_lock_type lock( sp ); |
| 469 | shared_lock_type lock2( sp2 ); |
| 470 | |
| 471 | STATIC_ASSERT( noexcept( lock.swap( lock2 ) ) ); |
| 472 | STATIC_ASSERT( noexcept( swap( lock, lock2 ) ) ); |
| 473 | |
| 474 | lock.swap( u&: lock2 ); |
| 475 | |
| 476 | BOOST_TEST_EQ( lock.mutex(), &sp2 ); |
| 477 | BOOST_TEST( lock.owns_lock() ); |
| 478 | BOOST_TEST( lock ); |
| 479 | |
| 480 | BOOST_TEST_EQ( lock2.mutex(), &sp ); |
| 481 | BOOST_TEST( lock2.owns_lock() ); |
| 482 | BOOST_TEST( lock2 ); |
| 483 | |
| 484 | swap( x&: lock, y&: lock2 ); |
| 485 | |
| 486 | BOOST_TEST_EQ( lock.mutex(), &sp ); |
| 487 | BOOST_TEST( lock.owns_lock() ); |
| 488 | BOOST_TEST( lock ); |
| 489 | |
| 490 | BOOST_TEST_EQ( lock2.mutex(), &sp2 ); |
| 491 | BOOST_TEST( lock2.owns_lock() ); |
| 492 | BOOST_TEST( lock2 ); |
| 493 | |
| 494 | BOOST_TEST_EQ( sp.shared_lock_count(), 1 ); |
| 495 | BOOST_TEST_EQ( sp2.shared_lock_count(), 1 ); |
| 496 | } |
| 497 | |
| 498 | { |
| 499 | shared_lock_type lock( sp ); |
| 500 | lock.swap( u&: lock ); |
| 501 | |
| 502 | BOOST_TEST_EQ( lock.mutex(), &sp ); |
| 503 | BOOST_TEST( lock.owns_lock() ); |
| 504 | BOOST_TEST( lock ); |
| 505 | } |
| 506 | } |
| 507 | |
| 508 | void release() { |
| 509 | dummy_lock sp; |
| 510 | |
| 511 | shared_lock_type lock( sp ); |
| 512 | |
| 513 | dummy_lock* pm = lock.release(); |
| 514 | |
| 515 | BOOST_TEST_EQ( pm, &sp ); |
| 516 | BOOST_TEST_EQ( lock.mutex(), nullptr ); |
| 517 | BOOST_TEST( !lock.owns_lock() ); |
| 518 | BOOST_TEST( !lock ); |
| 519 | |
| 520 | pm = lock.release(); |
| 521 | |
| 522 | BOOST_TEST_EQ( lock.mutex(), nullptr ); |
| 523 | BOOST_TEST( !lock.owns_lock() ); |
| 524 | BOOST_TEST( !lock ); |
| 525 | |
| 526 | BOOST_TEST_EQ( sp.shared_lock_count(), 1 ); |
| 527 | sp.unlock_shared(); |
| 528 | } |
| 529 | |
| 530 | } // namespace |
| 531 | |
| 532 | int main() { |
| 533 | sanity_tests(); |
| 534 | |
| 535 | default_constructor(); |
| 536 | locking_construtor(); |
| 537 | deferred_constructor(); |
| 538 | try_lock_constructor(); |
| 539 | adopt_lock_constructor(); |
| 540 | |
| 541 | move_constructor(); |
| 542 | move_assignment(); |
| 543 | |
| 544 | lock(); |
| 545 | unlock(); |
| 546 | try_lock(); |
| 547 | |
| 548 | swap(); |
| 549 | release(); |
| 550 | |
| 551 | return boost::report_errors(); |
| 552 | } |
| 553 | |
| 554 | #ifdef BOOST_NO_EXCEPTIONS |
| 555 | |
| 556 | namespace boost |
| 557 | { |
| 558 | |
| 559 | BOOST_NORETURN void throw_exception( std::exception const& ex, boost::source_location const& loc ) |
| 560 | { |
| 561 | std::fprintf( stderr, "Exception '%s' at %s:%d\n" , ex.what(), loc.file_name(), loc.line() ); |
| 562 | std::terminate(); |
| 563 | } |
| 564 | |
| 565 | } // namespace boost |
| 566 | |
| 567 | #endif |
| 568 | |