From 94c298e2a0ae409e283cab96c954a685bd865a70 Mon Sep 17 00:00:00 2001 From: Abseil Team Date: Tue, 23 Oct 2018 18:09:41 -0700 Subject: Export of internal Abseil changes. -- 441d1aa02483cdc510eb2fef012b31384fd8e3a6 by Eric Fiselier : Fix str_format with non-POSIX libc implementations. PiperOrigin-RevId: 218441122 -- da6190130e74222af6eb161a5593364341370370 by Jon Cohen : Refactor ExceptionSafetyTester::Test in order to remove the levels of indirection related to unpacking tuples. PiperOrigin-RevId: 218403355 GitOrigin-RevId: 441d1aa02483cdc510eb2fef012b31384fd8e3a6 Change-Id: I6f6b978eb96fe261e8ee41ecdce185e5356a601d --- absl/base/exception_safety_testing_test.cc | 12 ++ absl/base/internal/exception_safety_testing.cc | 4 + absl/base/internal/exception_safety_testing.h | 242 +++++++++++-------------- absl/strings/internal/str_format/output.cc | 27 ++- absl/strings/str_format_test.cc | 5 +- 5 files changed, 154 insertions(+), 136 deletions(-) diff --git a/absl/base/exception_safety_testing_test.cc b/absl/base/exception_safety_testing_test.cc index 106bc34b..7518264d 100644 --- a/absl/base/exception_safety_testing_test.cc +++ b/absl/base/exception_safety_testing_test.cc @@ -770,6 +770,18 @@ TEST(ExceptionCheckTest, ModifyingChecker) { .Test(invoker)); } +TEST(ExceptionSafetyTesterTest, ResetsCountdown) { + auto test = + testing::MakeExceptionSafetyTester() + .WithInitialValue(ThrowingValue<>()) + .WithContracts([](ThrowingValue<>*) { return AssertionSuccess(); }) + .WithOperation([](ThrowingValue<>*) {}); + ASSERT_TRUE(test.Test()); + // If the countdown isn't reset because there were no exceptions thrown, then + // this will fail with a termination from an unhandled exception + EXPECT_TRUE(test.Test()); +} + struct NonCopyable : public NonNegative { NonCopyable(const NonCopyable&) = delete; NonCopyable() : NonNegative{0} {} diff --git a/absl/base/internal/exception_safety_testing.cc b/absl/base/internal/exception_safety_testing.cc index f1d081f7..8207b7d7 100644 --- a/absl/base/internal/exception_safety_testing.cc +++ b/absl/base/internal/exception_safety_testing.cc @@ -23,6 +23,10 @@ exceptions_internal::NoThrowTag nothrow_ctor; exceptions_internal::StrongGuaranteeTagType strong_guarantee; +exceptions_internal::ExceptionSafetyTestBuilder<> MakeExceptionSafetyTester() { + return {}; +} + namespace exceptions_internal { int countdown = -1; diff --git a/absl/base/internal/exception_safety_testing.h b/absl/base/internal/exception_safety_testing.h index 5665a1b6..429f5c2f 100644 --- a/absl/base/internal/exception_safety_testing.h +++ b/absl/base/internal/exception_safety_testing.h @@ -190,70 +190,6 @@ class TrackedObject { ~TrackedObject() noexcept { ConstructorTracker::ObjectDestructed(this); } }; - -template -absl::optional TestSingleContractAtCountdownImpl( - const Factory& factory, const Operation& operation, int count, - const Contract& contract) { - auto t_ptr = factory(); - absl::optional current_res; - SetCountdown(count); - try { - operation(t_ptr.get()); - } catch (const exceptions_internal::TestException& e) { - current_res.emplace(contract(t_ptr.get())); - if (!current_res.value()) { - *current_res << e.what() << " failed contract check"; - } - } - UnsetCountdown(); - return current_res; -} - -template -absl::optional TestSingleContractAtCountdownImpl( - const Factory& factory, const Operation& operation, int count, - StrongGuaranteeTagType) { - using TPtr = typename decltype(factory())::pointer; - auto t_is_strong = [&](TPtr t) { return *t == *factory(); }; - return TestSingleContractAtCountdownImpl(factory, operation, count, - t_is_strong); -} - -template -int TestSingleContractAtCountdown( - const Factory& factory, const Operation& operation, int count, - const Contract& contract, - absl::optional* reduced_res) { - // If reduced_res is empty, it means the current call to - // TestSingleContractAtCountdown(...) is the first test being run so we do - // want to run it. Alternatively, if it's not empty (meaning a previous test - // has run) we want to check if it passed. If the previous test did pass, we - // want to contine running tests so we do want to run the current one. If it - // failed, we want to short circuit so as not to overwrite the AssertionResult - // output. If that's the case, we do not run the current test and instead we - // simply return. - if (!reduced_res->has_value() || reduced_res->value()) { - *reduced_res = - TestSingleContractAtCountdownImpl(factory, operation, count, contract); - } - return 0; -} - -template -inline absl::optional TestAllContractsAtCountdown( - const Factory& factory, const Operation& operation, int count, - const Contracts&... contracts) { - absl::optional reduced_res; - - // Run each checker, short circuiting after the first failure - int dummy[] = { - 0, (TestSingleContractAtCountdown(factory, operation, count, contracts, - &reduced_res))...}; - static_cast(dummy); - return reduced_res; -} - } // namespace exceptions_internal extern exceptions_internal::NoThrowTag nothrow_ctor; @@ -871,7 +807,7 @@ testing::AssertionResult TestNothrowOp(const Operation& operation) { namespace exceptions_internal { -// Dummy struct for ExceptionSafetyTester<> partial state. +// Dummy struct for ExceptionSafetyTestBuilder<> partial state. struct UninitializedT {}; template @@ -893,20 +829,97 @@ using EnableIfTestable = typename absl::enable_if_t< template -class ExceptionSafetyTester; +class ExceptionSafetyTestBuilder; } // namespace exceptions_internal -exceptions_internal::ExceptionSafetyTester<> MakeExceptionSafetyTester(); +/* + * Constructs an empty ExceptionSafetyTestBuilder. All + * ExceptionSafetyTestBuilder objects are immutable and all With[thing] mutation + * methods return new instances of ExceptionSafetyTestBuilder. + * + * In order to test a T for exception safety, a factory for that T, a testable + * operation, and at least one contract callback returning an assertion + * result must be applied using the respective methods. + */ +exceptions_internal::ExceptionSafetyTestBuilder<> MakeExceptionSafetyTester(); namespace exceptions_internal { +template +struct IsUniquePtr : std::false_type {}; + +template +struct IsUniquePtr> : std::true_type {}; + +template +struct FactoryPtrTypeHelper { + using type = decltype(std::declval()()); + + static_assert(IsUniquePtr::value, "Factories must return a unique_ptr"); +}; + +template +using FactoryPtrType = typename FactoryPtrTypeHelper::type; + +template +using FactoryElementType = typename FactoryPtrType::element_type; + +template +class ExceptionSafetyTest { + using Factory = std::function()>; + using Operation = std::function; + using Contract = std::function; + + public: + template + explicit ExceptionSafetyTest(const Factory& f, const Operation& op, + const Contracts&... contracts) + : factory_(f), operation_(op), contracts_{WrapContract(contracts)...} {} + + AssertionResult Test() const { + for (int count = 0;; ++count) { + exceptions_internal::ConstructorTracker ct(count); + + for (const auto& contract : contracts_) { + auto t_ptr = factory_(); + try { + SetCountdown(count); + operation_(t_ptr.get()); + // Unset for the case that the operation throws no exceptions, which + // would leave the countdown set and break the *next* exception safety + // test after this one. + UnsetCountdown(); + return AssertionSuccess(); + } catch (const exceptions_internal::TestException& e) { + if (!contract(t_ptr.get())) { + return AssertionFailure() << e.what() << " failed contract check"; + } + } + } + } + } + + private: + template + Contract WrapContract(const ContractFn& contract) { + return [contract](T* t_ptr) { return AssertionResult(contract(t_ptr)); }; + } + + Contract WrapContract(StrongGuaranteeTagType) { + return [this](T* t_ptr) { return AssertionResult(*factory_() == *t_ptr); }; + } + + Factory factory_; + Operation operation_; + std::vector contracts_; +}; /* * Builds a tester object that tests if performing a operation on a T follows * exception safety guarantees. Verification is done via contract assertion * callbacks applied to T instances post-throw. * - * Template parameters for ExceptionSafetyTester: + * Template parameters for ExceptionSafetyTestBuilder: * * - Factory: The factory object (passed in via tester.WithFactory(...) or * tester.WithInitialValue(...)) must be invocable with the signature @@ -933,13 +946,13 @@ namespace exceptions_internal { * please. */ template -class ExceptionSafetyTester { +class ExceptionSafetyTestBuilder { public: /* - * Returns a new ExceptionSafetyTester with an included T factory based on the - * provided T instance. The existing factory will not be included in the newly - * created tester instance. The created factory returns a new T instance by - * copy-constructing the provided const T& t. + * Returns a new ExceptionSafetyTestBuilder with an included T factory based + * on the provided T instance. The existing factory will not be included in + * the newly created tester instance. The created factory returns a new T + * instance by copy-constructing the provided const T& t. * * Preconditions for tester.WithInitialValue(const T& t): * @@ -948,41 +961,41 @@ class ExceptionSafetyTester { * tester.WithFactory(...). */ template - ExceptionSafetyTester, Operation, Contracts...> + ExceptionSafetyTestBuilder, Operation, Contracts...> WithInitialValue(const T& t) const { return WithFactory(DefaultFactory(t)); } /* - * Returns a new ExceptionSafetyTester with the provided T factory included. - * The existing factory will not be included in the newly-created tester - * instance. This method is intended for use with types lacking a copy + * Returns a new ExceptionSafetyTestBuilder with the provided T factory + * included. The existing factory will not be included in the newly-created + * tester instance. This method is intended for use with types lacking a copy * constructor. Types that can be copy-constructed should instead use the * method tester.WithInitialValue(...). */ template - ExceptionSafetyTester, Operation, Contracts...> + ExceptionSafetyTestBuilder, Operation, Contracts...> WithFactory(const NewFactory& new_factory) const { return {new_factory, operation_, contracts_}; } /* - * Returns a new ExceptionSafetyTester with the provided testable operation - * included. The existing operation will not be included in the newly created - * tester. + * Returns a new ExceptionSafetyTestBuilder with the provided testable + * operation included. The existing operation will not be included in the + * newly created tester. */ template - ExceptionSafetyTester, Contracts...> + ExceptionSafetyTestBuilder, Contracts...> WithOperation(const NewOperation& new_operation) const { return {factory_, new_operation, contracts_}; } /* - * Returns a new ExceptionSafetyTester with the provided MoreContracts... + * Returns a new ExceptionSafetyTestBuilder with the provided MoreContracts... * combined with the Contracts... that were already included in the instance * on which the method was called. Contracts... cannot be removed or replaced - * once added to an ExceptionSafetyTester instance. A fresh object must be - * created in order to get an empty Contracts... list. + * once added to an ExceptionSafetyTestBuilder instance. A fresh object must + * be created in order to get an empty Contracts... list. * * In addition to passing in custom contract assertion callbacks, this method * accepts `testing::strong_guarantee` as an argument which checks T instances @@ -991,8 +1004,8 @@ class ExceptionSafetyTester { * properly rolled back. */ template - ExceptionSafetyTester...> + ExceptionSafetyTestBuilder...> WithContracts(const MoreContracts&... more_contracts) const { return { factory_, operation_, @@ -1039,48 +1052,27 @@ class ExceptionSafetyTester { typename LazyOperation = Operation, typename = EnableIfTestable> testing::AssertionResult Test() const { - return TestImpl(operation_, absl::index_sequence_for()); + return Test(operation_); } private: template - friend class ExceptionSafetyTester; + friend class ExceptionSafetyTestBuilder; - friend ExceptionSafetyTester<> testing::MakeExceptionSafetyTester(); + friend ExceptionSafetyTestBuilder<> testing::MakeExceptionSafetyTester(); - ExceptionSafetyTester() {} + ExceptionSafetyTestBuilder() {} - ExceptionSafetyTester(const Factory& f, const Operation& o, - const std::tuple& i) + ExceptionSafetyTestBuilder(const Factory& f, const Operation& o, + const std::tuple& i) : factory_(f), operation_(o), contracts_(i) {} template - testing::AssertionResult TestImpl(const SelectedOperation& selected_operation, + testing::AssertionResult TestImpl(SelectedOperation selected_operation, absl::index_sequence) const { - // Starting from 0 and counting upwards until one of the exit conditions is - // hit... - for (int count = 0;; ++count) { - exceptions_internal::ConstructorTracker ct(count); - - // Run the full exception safety test algorithm for the current countdown - auto reduced_res = - TestAllContractsAtCountdown(factory_, selected_operation, count, - std::get(contracts_)...); - // If there is no value in the optional, no contracts were run because no - // exception was thrown. This means that the test is complete and the loop - // can exit successfully. - if (!reduced_res.has_value()) { - return testing::AssertionSuccess(); - } - // If the optional is not empty and the value is falsy, an contract check - // failed so the test must exit to propegate the failure. - if (!reduced_res.value()) { - return reduced_res.value(); - } - // If the optional is not empty and the value is not falsy, it means - // exceptions were thrown but the contracts passed so the test must - // continue to run. - } + return ExceptionSafetyTest>( + factory_, selected_operation, std::get(contracts_)...) + .Test(); } Factory factory_; @@ -1090,20 +1082,6 @@ class ExceptionSafetyTester { } // namespace exceptions_internal -/* - * Constructs an empty ExceptionSafetyTester. All ExceptionSafetyTester - * objects are immutable and all With[thing] mutation methods return new - * instances of ExceptionSafetyTester. - * - * In order to test a T for exception safety, a factory for that T, a testable - * operation, and at least one contract callback returning an assertion - * result must be applied using the respective methods. - */ -inline exceptions_internal::ExceptionSafetyTester<> -MakeExceptionSafetyTester() { - return {}; -} - } // namespace testing #endif // ABSL_BASE_INTERNAL_EXCEPTION_SAFETY_TESTING_H_ diff --git a/absl/strings/internal/str_format/output.cc b/absl/strings/internal/str_format/output.cc index 5c3795b7..d7fef69b 100644 --- a/absl/strings/internal/str_format/output.cc +++ b/absl/strings/internal/str_format/output.cc @@ -20,6 +20,16 @@ namespace absl { namespace str_format_internal { +namespace { +struct ClearErrnoGuard { + ClearErrnoGuard() : old_value(errno) { errno = 0; } + ~ClearErrnoGuard() { + if (!errno) errno = old_value; + } + int old_value; +}; +} // namespace + void BufferRawSink::Write(string_view v) { size_t to_write = std::min(v.size(), size_); std::memcpy(buffer_, v.data(), to_write); @@ -30,14 +40,27 @@ void BufferRawSink::Write(string_view v) { void FILERawSink::Write(string_view v) { while (!v.empty() && !error_) { + // Reset errno to zero in case the libc implementation doesn't set errno + // when a failure occurs. + ClearErrnoGuard guard; + if (size_t result = std::fwrite(v.data(), 1, v.size(), output_)) { // Some progress was made. count_ += result; v.remove_prefix(result); } else { - // Some error occurred. - if (errno != EINTR) { + if (errno == EINTR) { + continue; + } else if (errno) { error_ = errno; + } else if (std::ferror(output_)) { + // Non-POSIX compliant libc implementations may not set errno, so we + // have check the streams error indicator. + error_ = EBADF; + } else { + // We're likely on a non-POSIX system that encountered EINTR but had no + // way of reporting it. + continue; } } } diff --git a/absl/strings/str_format_test.cc b/absl/strings/str_format_test.cc index ea9a3a17..87ed234f 100644 --- a/absl/strings/str_format_test.cc +++ b/absl/strings/str_format_test.cc @@ -242,6 +242,7 @@ class TempFile { std::string ReadFile() { std::fseek(file_, 0, SEEK_END); int size = std::ftell(file_); + EXPECT_GT(size, 0); std::rewind(file_); std::string str(2 * size, ' '); int read_bytes = std::fread(&str[0], 1, str.size(), file_); @@ -270,7 +271,7 @@ TEST_F(FormatEntryPointTest, FPrintFError) { EXPECT_EQ(errno, EBADF); } -#if __GNUC__ +#if __GLIBC__ TEST_F(FormatEntryPointTest, FprintfTooLarge) { std::FILE* f = std::fopen("/dev/null", "w"); int width = 2000000000; @@ -297,7 +298,7 @@ TEST_F(FormatEntryPointTest, PrintF) { EXPECT_EQ(result, 30); EXPECT_EQ(tmp.ReadFile(), "STRING: ABC NUMBER: -000000019"); } -#endif // __GNUC__ +#endif // __GLIBC__ TEST_F(FormatEntryPointTest, SNPrintF) { char buffer[16]; -- cgit v1.2.3