diff options
Diffstat (limited to 'absl/flags/internal/registry.cc')
| -rw-r--r-- | absl/flags/internal/registry.cc | 258 |
1 files changed, 82 insertions, 176 deletions
diff --git a/absl/flags/internal/registry.cc b/absl/flags/internal/registry.cc index e39264e5..e434a859 100644 --- a/absl/flags/internal/registry.cc +++ b/absl/flags/internal/registry.cc @@ -15,9 +15,20 @@ #include "absl/flags/internal/registry.h" -#include "absl/base/dynamic_annotations.h" +#include <assert.h> +#include <stdlib.h> + +#include <functional> +#include <map> +#include <memory> +#include <string> +#include <utility> +#include <vector> + +#include "absl/base/config.h" #include "absl/base/internal/raw_logging.h" -#include "absl/flags/config.h" +#include "absl/base/thread_annotations.h" +#include "absl/flags/internal/commandlineflag.h" #include "absl/flags/usage_config.h" #include "absl/strings/str_cat.h" #include "absl/strings/string_view.h" @@ -30,20 +41,8 @@ // set it. namespace absl { -inline namespace lts_2019_08_08 { +ABSL_NAMESPACE_BEGIN namespace flags_internal { -namespace { - -void DestroyFlag(CommandLineFlag* flag) NO_THREAD_SAFETY_ANALYSIS { - flag->Destroy(); - - // CommandLineFlag handle object is heap allocated for non Abseil Flags. - if (!flag->IsAbseilFlag()) { - delete flag; - } -} - -} // namespace // -------------------------------------------------------------------- // FlagRegistry @@ -58,17 +57,13 @@ void DestroyFlag(CommandLineFlag* flag) NO_THREAD_SAFETY_ANALYSIS { class FlagRegistry { public: FlagRegistry() = default; - ~FlagRegistry() { - for (auto& p : flags_) { - DestroyFlag(p.second); - } - } + ~FlagRegistry() = default; // Store a flag in this registry. Takes ownership of *flag. void RegisterFlag(CommandLineFlag* flag); - void Lock() EXCLUSIVE_LOCK_FUNCTION(lock_) { lock_.Lock(); } - void Unlock() UNLOCK_FUNCTION(lock_) { lock_.Unlock(); } + void Lock() ABSL_EXCLUSIVE_LOCK_FUNCTION(lock_) { lock_.Lock(); } + void Unlock() ABSL_UNLOCK_FUNCTION(lock_) { lock_.Unlock(); } // Returns the flag object for the specified name, or nullptr if not found. // Will emit a warning if a 'retired' flag is specified. @@ -114,6 +109,7 @@ class FlagRegistryLock { FlagRegistry* const fr_; }; +void DestroyRetiredFlag(CommandLineFlag* flag); } // namespace void FlagRegistry::RegisterFlag(CommandLineFlag* flag) { @@ -131,7 +127,7 @@ void FlagRegistry::RegisterFlag(CommandLineFlag* flag) { (flag->IsRetired() ? old_flag->Filename() : flag->Filename()), "'."), true); - } else if (flag->op != old_flag->op) { + } else if (flag->TypeId() != old_flag->TypeId()) { flags_internal::ReportUsageError( absl::StrCat("Flag '", flag->Name(), "' was defined more than once but with " @@ -141,8 +137,8 @@ void FlagRegistry::RegisterFlag(CommandLineFlag* flag) { flag->Typename(), "', respectively."), true); } else if (old_flag->IsRetired()) { - // Retired definitions are idempotent. Just keep the old one. - DestroyFlag(flag); + // Retired flag can just be deleted. + DestroyRetiredFlag(flag); return; } else if (old_flag->Filename() != flag->Filename()) { flags_internal::ReportUsageError( @@ -201,112 +197,34 @@ CommandLineFlag* FlagRegistry::FindRetiredFlagLocked(absl::string_view name) { class FlagSaverImpl { public: - // Constructs an empty FlagSaverImpl object. - FlagSaverImpl() {} - ~FlagSaverImpl() { - // reclaim memory from each of our CommandLineFlags - for (const SavedFlag& src : backup_registry_) { - Delete(src.op, src.current); - Delete(src.op, src.default_value); - } - } + FlagSaverImpl() = default; + FlagSaverImpl(const FlagSaverImpl&) = delete; + void operator=(const FlagSaverImpl&) = delete; // Saves the flag states from the flag registry into this object. // It's an error to call this more than once. - // Must be called when the registry mutex is not held. void SaveFromRegistry() { assert(backup_registry_.empty()); // call only once! - SavedFlag saved; flags_internal::ForEachFlag([&](flags_internal::CommandLineFlag* flag) { - if (flag->IsRetired()) return; - - saved.name = flag->Name(); - saved.op = flag->op; - saved.marshalling_op = flag->marshalling_op; - { - absl::MutexLock l(flag->InitFlagIfNecessary()); - saved.validator = flag->validator; - saved.modified = flag->modified; - saved.on_command_line = flag->on_command_line; - saved.current = Clone(saved.op, flag->cur); - saved.default_value = Clone(saved.op, flag->def); - saved.counter = flag->counter; + if (auto flag_state = flag->SaveState()) { + backup_registry_.emplace_back(std::move(flag_state)); } - backup_registry_.push_back(saved); }); } - // Restores the saved flag states into the flag registry. We - // assume no flags were added or deleted from the registry since - // the SaveFromRegistry; if they were, that's trouble! Must be - // called when the registry mutex is not held. + // Restores the saved flag states into the flag registry. void RestoreToRegistry() { - FlagRegistry* const global_registry = FlagRegistry::GlobalRegistry(); - FlagRegistryLock frl(global_registry); - for (const SavedFlag& src : backup_registry_) { - CommandLineFlag* flag = global_registry->FindFlagLocked(src.name); - // If null, flag got deleted from registry. - if (!flag) continue; - - bool restored = false; - { - absl::MutexLock l(flag->InitFlagIfNecessary()); - flag->validator = src.validator; - flag->modified = src.modified; - flag->on_command_line = src.on_command_line; - if (flag->counter != src.counter || - ChangedDirectly(flag, src.default_value, flag->def)) { - restored = true; - Copy(src.op, src.default_value, flag->def); - } - if (flag->counter != src.counter || - ChangedDirectly(flag, src.current, flag->cur)) { - restored = true; - Copy(src.op, src.current, flag->cur); - UpdateCopy(flag); - flag->InvokeCallback(); - } - } - - if (restored) { - flag->counter++; - - // Revalidate the flag because the validator might store state based - // on the flag's value, which just changed due to the restore. - // Failing validation is ignored because it's assumed that the flag - // was valid previously and there's little that can be done about it - // here, anyway. - flag->ValidateInputValue(flag->CurrentValue()); - - ABSL_INTERNAL_LOG( - INFO, absl::StrCat("Restore saved value of ", flag->Name(), ": ", - Unparse(src.marshalling_op, src.current))); - } + for (const auto& flag_state : backup_registry_) { + flag_state->Restore(); } } private: - struct SavedFlag { - absl::string_view name; - FlagOpFn op; - FlagMarshallingOpFn marshalling_op; - int64_t counter; - bool modified; - bool on_command_line; - bool (*validator)(); - const void* current; // nullptr after restore - const void* default_value; // nullptr after restore - }; - - std::vector<SavedFlag> backup_registry_; - - FlagSaverImpl(const FlagSaverImpl&); // no copying! - void operator=(const FlagSaverImpl&); + std::vector<std::unique_ptr<flags_internal::FlagStateInterface>> + backup_registry_; }; -FlagSaver::FlagSaver() : impl_(new FlagSaverImpl()) { - impl_->SaveFromRegistry(); -} +FlagSaver::FlagSaver() : impl_(new FlagSaverImpl) { impl_->SaveFromRegistry(); } void FlagSaver::Ignore() { delete impl_; @@ -321,44 +239,6 @@ FlagSaver::~FlagSaver() { } // -------------------------------------------------------------------- -// GetAllFlags() -// The main way the FlagRegistry class exposes its data. This -// returns, as strings, all the info about all the flags in -// the main registry, sorted first by filename they are defined -// in, and then by flagname. -// -------------------------------------------------------------------- - -struct FilenameFlagnameLess { - bool operator()(const CommandLineFlagInfo& a, - const CommandLineFlagInfo& b) const { - int cmp = absl::string_view(a.filename).compare(b.filename); - if (cmp != 0) return cmp < 0; - return a.name < b.name; - } -}; - -void FillCommandLineFlagInfo(CommandLineFlag* flag, - CommandLineFlagInfo* result) { - result->name = std::string(flag->Name()); - result->type = std::string(flag->Typename()); - result->description = flag->Help(); - result->filename = flag->Filename(); - - if (!flag->IsAbseilFlag()) { - if (!flag->IsModified() && ChangedDirectly(flag, flag->cur, flag->def)) { - flag->modified = true; - } - } - - result->current_value = flag->CurrentValue(); - result->default_value = flag->DefaultValue(); - result->is_default = !flag->IsModified(); - result->has_validator_fn = flag->HasValidatorFn(); - absl::MutexLock l(flag->InitFlagIfNecessary()); - result->flag_ptr = flag->IsAbseilFlag() ? nullptr : flag->cur; -} - -// -------------------------------------------------------------------- CommandLineFlag* FindCommandLineFlag(absl::string_view name) { if (name.empty()) return nullptr; @@ -393,21 +273,6 @@ void ForEachFlag(std::function<void(CommandLineFlag*)> visitor) { // -------------------------------------------------------------------- -void GetAllFlags(std::vector<CommandLineFlagInfo>* OUTPUT) { - flags_internal::ForEachFlag([&](CommandLineFlag* flag) { - if (flag->IsRetired()) return; - - CommandLineFlagInfo fi; - FillCommandLineFlagInfo(flag, &fi); - OUTPUT->push_back(fi); - }); - - // Now sort the flags, first by filename they occur in, then alphabetically - std::sort(OUTPUT->begin(), OUTPUT->end(), FilenameFlagnameLess()); -} - -// -------------------------------------------------------------------- - bool RegisterCommandLineFlag(CommandLineFlag* flag) { FlagRegistry::GlobalRegistry()->RegisterFlag(flag); return true; @@ -415,14 +280,55 @@ bool RegisterCommandLineFlag(CommandLineFlag* flag) { // -------------------------------------------------------------------- -bool Retire(FlagOpFn ops, FlagMarshallingOpFn marshalling_ops, - const char* name) { - auto* flag = new CommandLineFlag( - name, - /*help_text=*/absl::flags_internal::HelpText::FromStaticCString(nullptr), - /*filename_arg=*/"RETIRED", ops, marshalling_ops, - /*initial_value_gen=*/nullptr, - /*retired_arg=*/true, nullptr, nullptr); +namespace { + +class RetiredFlagObj final : public flags_internal::CommandLineFlag { + public: + constexpr RetiredFlagObj(const char* name, FlagStaticTypeId 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_; } + std::string Help() const override { return ""; } + bool IsRetired() const override { return true; } + bool IsModified() const override { return false; } + bool IsSpecifiedOnCommandLine() const override { return false; } + std::string DefaultValue() const override { return ""; } + std::string CurrentValue() const override { return ""; } + + // Any input is valid + bool ValidateInputValue(absl::string_view) const override { return true; } + + std::unique_ptr<flags_internal::FlagStateInterface> SaveState() override { + return nullptr; + } + + bool SetFromString(absl::string_view, flags_internal::FlagSettingMode, + flags_internal::ValueSource, std::string*) override { + return false; + } + + void CheckDefaultValueParsingRoundtrip() const override {} + + void Read(void*) const override {} + + // Data members + const char* const name_; + const FlagStaticTypeId type_id_; +}; + +void DestroyRetiredFlag(flags_internal::CommandLineFlag* flag) { + assert(flag->IsRetired()); + delete static_cast<RetiredFlagObj*>(flag); +} + +} // namespace + +bool Retire(const char* name, FlagStaticTypeId type_id) { + auto* flag = new flags_internal::RetiredFlagObj(name, type_id); FlagRegistry::GlobalRegistry()->RegisterFlag(flag); return true; } @@ -441,5 +347,5 @@ bool IsRetiredFlag(absl::string_view name, bool* type_is_bool) { } } // namespace flags_internal -} // inline namespace lts_2019_08_08 +ABSL_NAMESPACE_END } // namespace absl |