diff options
Diffstat (limited to 'absl/flags')
| -rw-r--r-- | absl/flags/BUILD.bazel | 1 | ||||
| -rw-r--r-- | absl/flags/CMakeLists.txt | 1 | ||||
| -rw-r--r-- | absl/flags/internal/commandlineflag.h | 22 | ||||
| -rw-r--r-- | absl/flags/internal/flag.cc | 34 | ||||
| -rw-r--r-- | absl/flags/internal/flag.h | 46 | ||||
| -rw-r--r-- | absl/flags/internal/registry.cc | 8 | ||||
| -rw-r--r-- | absl/flags/internal/registry.h | 4 |
7 files changed, 64 insertions, 52 deletions
diff --git a/absl/flags/BUILD.bazel b/absl/flags/BUILD.bazel index 908e77612be6..4b51d9d45207 100644 --- a/absl/flags/BUILD.bazel +++ b/absl/flags/BUILD.bazel @@ -147,6 +147,7 @@ cc_library( ":marshalling", "//absl/base:config", "//absl/base:core_headers", + "//absl/base:fast_type_id", "//absl/strings", "//absl/types:optional", ], diff --git a/absl/flags/CMakeLists.txt b/absl/flags/CMakeLists.txt index 01cf09b1b52a..2204b0ff2dd8 100644 --- a/absl/flags/CMakeLists.txt +++ b/absl/flags/CMakeLists.txt @@ -128,6 +128,7 @@ absl_cc_library( ${ABSL_DEFAULT_LINKOPTS} DEPS absl::config + absl::fast_type_id absl::flags_config absl::flags_marshalling absl::core_headers diff --git a/absl/flags/internal/commandlineflag.h b/absl/flags/internal/commandlineflag.h index 338a1228dacb..ef992f7f478d 100644 --- a/absl/flags/internal/commandlineflag.h +++ b/absl/flags/internal/commandlineflag.h @@ -24,6 +24,7 @@ #include <typeinfo> #include "absl/base/config.h" +#include "absl/base/internal/fast_type_id.h" #include "absl/base/macros.h" #include "absl/flags/config.h" #include "absl/flags/marshalling.h" @@ -34,23 +35,12 @@ namespace absl { ABSL_NAMESPACE_BEGIN namespace flags_internal { -// An alias for flag static type id. Values of type identify the flag value type -// simialarly to typeid(T), but without relying on RTTI being available. In most +// An alias for flag fast type id. This value identifies the flag value type +// simialarly to typeid(T), without relying on RTTI being available. In most // cases this id is enough to uniquely identify the flag's value type. In a few // cases we'll have to resort to using actual RTTI implementation if it is // available. -using FlagStaticTypeId = void* (*)(); - -// Address of this function template is used in current implementation as a flag -// static type id. -template <typename T> -void* FlagStaticTypeIdGen() { -#if defined(ABSL_FLAGS_INTERNAL_HAS_RTTI) - return const_cast<std::type_info*>(&typeid(T)); -#else - return nullptr; -#endif -} +using FlagFastTypeId = base_internal::FastTypeIdType; // Options that control SetCommandLineOptionWithMode. enum FlagSettingMode { @@ -97,7 +87,7 @@ class CommandLineFlag { // Return true iff flag has type T. template <typename T> inline bool IsOfType() const { - return TypeId() == &flags_internal::FlagStaticTypeIdGen<T>; + return TypeId() == base_internal::FastTypeId<T>(); } // Attempts to retrieve the flag value. Returns value on success, @@ -150,7 +140,7 @@ class CommandLineFlag { // Returns true iff this is a handle to an Abseil Flag. virtual bool IsAbseilFlag() const; // Returns id of the flag's value type. - virtual FlagStaticTypeId TypeId() const = 0; + virtual FlagFastTypeId TypeId() const = 0; virtual bool IsModified() const = 0; virtual bool IsSpecifiedOnCommandLine() const = 0; virtual std::string DefaultValue() const = 0; diff --git a/absl/flags/internal/flag.cc b/absl/flags/internal/flag.cc index 5b4499abe47e..f3c424ad83d8 100644 --- a/absl/flags/internal/flag.cc +++ b/absl/flags/internal/flag.cc @@ -48,9 +48,9 @@ const char kStrippedFlagHelp[] = "\001\002\003\004 (unknown) \004\003\002\001"; namespace { // Currently we only validate flag values for user-defined flag types. -bool ShouldValidateFlagValue(FlagStaticTypeId flag_type_id) { +bool ShouldValidateFlagValue(FlagFastTypeId flag_type_id) { #define DONT_VALIDATE(T) \ - if (flag_type_id == &FlagStaticTypeIdGen<T>) return false; + if (flag_type_id == base_internal::FastTypeId<T>()) return false; ABSL_FLAGS_INTERNAL_BUILTIN_TYPES(DONT_VALIDATE) #undef DONT_VALIDATE @@ -161,24 +161,24 @@ absl::Mutex* FlagImpl::DataGuard() const { return reinterpret_cast<absl::Mutex*>(&data_guard_); } -void FlagImpl::AssertValidType(FlagStaticTypeId type_id) const { - FlagStaticTypeId this_type_id = flags_internal::StaticTypeId(op_); +void FlagImpl::AssertValidType(FlagFastTypeId rhs_type_id, + const std::type_info* (*gen_rtti)()) const { + FlagFastTypeId lhs_type_id = flags_internal::FastTypeId(op_); - // `type_id` is the type id corresponding to the declaration visibile at the - // call site. `this_type_id` is the type id corresponding to the type stored - // during flag definition. They must match for this operation to be - // well-defined. - if (ABSL_PREDICT_TRUE(type_id == this_type_id)) return; + // `rhs_type_id` is the fast type id corresponding to the declaration + // visibile at the call site. `lhs_type_id` is the fast type id + // corresponding to the type specified in flag definition. They must match + // for this operation to be well-defined. + if (ABSL_PREDICT_TRUE(lhs_type_id == rhs_type_id)) return; - void* lhs_runtime_type_id = type_id(); - void* rhs_runtime_type_id = this_type_id(); + const std::type_info* lhs_runtime_type_id = + flags_internal::RuntimeTypeId(op_); + const std::type_info* rhs_runtime_type_id = (*gen_rtti)(); if (lhs_runtime_type_id == rhs_runtime_type_id) return; #if defined(ABSL_FLAGS_INTERNAL_HAS_RTTI) - if (*reinterpret_cast<std::type_info*>(lhs_runtime_type_id) == - *reinterpret_cast<std::type_info*>(rhs_runtime_type_id)) - return; + if (*lhs_runtime_type_id == *rhs_runtime_type_id) return; #endif ABSL_INTERNAL_LOG( @@ -233,8 +233,8 @@ std::string FlagImpl::Help() const { : help_.gen_func(); } -FlagStaticTypeId FlagImpl::TypeId() const { - return flags_internal::StaticTypeId(op_); +FlagFastTypeId FlagImpl::TypeId() const { + return flags_internal::FastTypeId(op_); } bool FlagImpl::IsModified() const { @@ -429,7 +429,7 @@ void FlagImpl::Read(void* dst) const { void FlagImpl::Write(const void* src) { absl::MutexLock l(DataGuard()); - if (ShouldValidateFlagValue(flags_internal::StaticTypeId(op_))) { + if (ShouldValidateFlagValue(flags_internal::FastTypeId(op_))) { std::unique_ptr<void, DynValueDeleter> obj{flags_internal::Clone(op_, src), DynValueDeleter{op_}}; std::string ignored_error; diff --git a/absl/flags/internal/flag.h b/absl/flags/internal/flag.h index 19119bbb6193..c1bf8652815d 100644 --- a/absl/flags/internal/flag.h +++ b/absl/flags/internal/flag.h @@ -23,6 +23,7 @@ #include <memory> #include <string> #include <type_traits> +#include <typeinfo> #include "absl/base/call_once.h" #include "absl/base/config.h" @@ -50,7 +51,8 @@ enum class FlagOp { kCopy, kCopyConstruct, kSizeof, - kStaticTypeId, + kFastTypeId, + kRuntimeTypeId, kParse, kUnparse, kValueOffset, @@ -96,10 +98,15 @@ inline size_t Sizeof(FlagOpFn op) { return static_cast<size_t>(reinterpret_cast<intptr_t>( op(FlagOp::kSizeof, nullptr, nullptr, nullptr))); } -// Returns static type id coresponding to the value type. -inline FlagStaticTypeId StaticTypeId(FlagOpFn op) { - return reinterpret_cast<FlagStaticTypeId>( - op(FlagOp::kStaticTypeId, nullptr, nullptr, nullptr)); +// Returns fast type id coresponding to the value type. +inline FlagFastTypeId FastTypeId(FlagOpFn op) { + return reinterpret_cast<FlagFastTypeId>( + op(FlagOp::kFastTypeId, nullptr, nullptr, nullptr)); +} +// Returns fast type id coresponding to the value type. +inline const std::type_info* RuntimeTypeId(FlagOpFn op) { + return reinterpret_cast<const std::type_info*>( + op(FlagOp::kRuntimeTypeId, nullptr, nullptr, nullptr)); } // Returns offset of the field value_ from the field impl_ inside of // absl::Flag<T> data. Given FlagImpl pointer p you can get the @@ -112,6 +119,16 @@ inline ptrdiff_t ValueOffset(FlagOpFn op) { op(FlagOp::kValueOffset, nullptr, nullptr, nullptr))); } +// Returns an address of RTTI's typeid(T). +template <typename T> +inline const std::type_info* GenRuntimeTypeId() { +#if defined(ABSL_FLAGS_INTERNAL_HAS_RTTI) + return &typeid(T); +#else + return nullptr; +#endif +} + /////////////////////////////////////////////////////////////////////////////// // Flag help auxiliary structs. @@ -374,9 +391,10 @@ class FlagImpl final : public flags_internal::CommandLineFlag { // For example if flag is declared as absl::Flag<int> FLAGS_foo, a call to // absl::GetFlag(FLAGS_foo) validates that the type of FLAGS_foo is indeed // int. To do that we pass the "assumed" type id (which is deduced from type - // int) as an argument `op`, which is in turn is validated against the type id - // stored in flag object by flag definition statement. - void AssertValidType(FlagStaticTypeId type_id) const; + // int) as an argument `type_id`, which is in turn is validated against the + // type id stored in flag object by flag definition statement. + void AssertValidType(FlagFastTypeId type_id, + const std::type_info* (*gen_rtti)()) const; private: template <typename T> @@ -433,7 +451,7 @@ class FlagImpl final : public flags_internal::CommandLineFlag { std::string Filename() const override; absl::string_view Typename() const override; std::string Help() const override; - FlagStaticTypeId TypeId() const override; + FlagFastTypeId TypeId() const override; bool IsModified() const override ABSL_LOCKS_EXCLUDED(*DataGuard()); bool IsSpecifiedOnCommandLine() const override ABSL_LOCKS_EXCLUDED(*DataGuard()); @@ -539,14 +557,14 @@ class Flag { U u; #if !defined(NDEBUG) - impl_.AssertValidType(&flags_internal::FlagStaticTypeIdGen<T>); + impl_.AssertValidType(base_internal::FastTypeId<T>(), &GenRuntimeTypeId<T>); #endif if (!value_.Get(&u.value)) impl_.Read(&u.value); return std::move(u.value); } void Set(const T& v) { - impl_.AssertValidType(&flags_internal::FlagStaticTypeIdGen<T>); + impl_.AssertValidType(base_internal::FastTypeId<T>(), &GenRuntimeTypeId<T>); impl_.Write(&v); } void SetCallback(const FlagCallbackFunc mutation_callback) { @@ -595,8 +613,10 @@ void* FlagOps(FlagOp op, const void* v1, void* v2, void* v3) { return nullptr; case FlagOp::kSizeof: return reinterpret_cast<void*>(static_cast<uintptr_t>(sizeof(T))); - case FlagOp::kStaticTypeId: - return reinterpret_cast<void*>(&FlagStaticTypeIdGen<T>); + case FlagOp::kFastTypeId: + return const_cast<void*>(base_internal::FastTypeId<T>()); + case FlagOp::kRuntimeTypeId: + return const_cast<std::type_info*>(GenRuntimeTypeId<T>()); case FlagOp::kParse: { // Initialize the temporary instance of type T based on current value in // destination (which is going to be flag's default value). diff --git a/absl/flags/internal/registry.cc b/absl/flags/internal/registry.cc index 9ed912140ee7..eb619c7086ad 100644 --- a/absl/flags/internal/registry.cc +++ b/absl/flags/internal/registry.cc @@ -284,14 +284,14 @@ namespace { class RetiredFlagObj final : public flags_internal::CommandLineFlag { public: - constexpr RetiredFlagObj(const char* name, FlagStaticTypeId type_id) + constexpr RetiredFlagObj(const char* name, FlagFastTypeId type_id) : name_(name), type_id_(type_id) {} private: absl::string_view Name() const override { return name_; } std::string Filename() const override { return "RETIRED"; } absl::string_view Typename() const override { return ""; } - FlagStaticTypeId TypeId() const override { return type_id_; } + FlagFastTypeId TypeId() const override { return type_id_; } std::string Help() const override { return ""; } bool IsRetired() const override { return true; } bool IsModified() const override { return false; } @@ -317,7 +317,7 @@ class RetiredFlagObj final : public flags_internal::CommandLineFlag { // Data members const char* const name_; - const FlagStaticTypeId type_id_; + const FlagFastTypeId type_id_; }; void DestroyRetiredFlag(flags_internal::CommandLineFlag* flag) { @@ -327,7 +327,7 @@ void DestroyRetiredFlag(flags_internal::CommandLineFlag* flag) { } // namespace -bool Retire(const char* name, FlagStaticTypeId type_id) { +bool Retire(const char* name, FlagFastTypeId type_id) { auto* flag = new flags_internal::RetiredFlagObj(name, type_id); FlagRegistry::GlobalRegistry()->RegisterFlag(flag); return true; diff --git a/absl/flags/internal/registry.h b/absl/flags/internal/registry.h index 69ff889fb100..af8ed6b99b78 100644 --- a/absl/flags/internal/registry.h +++ b/absl/flags/internal/registry.h @@ -79,12 +79,12 @@ bool RegisterCommandLineFlag(CommandLineFlag*); // // Retire flag with name "name" and type indicated by ops. -bool Retire(const char* name, FlagStaticTypeId type_id); +bool Retire(const char* name, FlagFastTypeId type_id); // Registered a retired flag with name 'flag_name' and type 'T'. template <typename T> inline bool RetiredFlag(const char* flag_name) { - return flags_internal::Retire(flag_name, &FlagStaticTypeIdGen<T>); + return flags_internal::Retire(flag_name, base_internal::FastTypeId<T>()); } // If the flag is retired, returns true and indicates in |*type_is_bool| |