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Diffstat (limited to 'absl/time/internal/cctz/src/time_zone_impl.h')
-rw-r--r-- | absl/time/internal/cctz/src/time_zone_impl.h | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/absl/time/internal/cctz/src/time_zone_impl.h b/absl/time/internal/cctz/src/time_zone_impl.h new file mode 100644 index 00000000..2c1c30b6 --- /dev/null +++ b/absl/time/internal/cctz/src/time_zone_impl.h @@ -0,0 +1,97 @@ +// Copyright 2016 Google Inc. All Rights Reserved. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +#ifndef ABSL_TIME_INTERNAL_CCTZ_TIME_ZONE_IMPL_H_ +#define ABSL_TIME_INTERNAL_CCTZ_TIME_ZONE_IMPL_H_ + +#include <memory> +#include <string> + +#include "absl/time/internal/cctz/include/cctz/civil_time.h" +#include "absl/time/internal/cctz/include/cctz/time_zone.h" +#include "time_zone_if.h" +#include "time_zone_info.h" + +namespace absl { +namespace time_internal { +namespace cctz { + +// time_zone::Impl is the internal object referenced by a cctz::time_zone. +class time_zone::Impl { + public: + // The UTC time zone. Also used for other time zones that fail to load. + static time_zone UTC(); + + // Load a named time zone. Returns false if the name is invalid, or if + // some other kind of error occurs. Note that loading "UTC" never fails. + static bool LoadTimeZone(const std::string& name, time_zone* tz); + + // Dereferences the time_zone to obtain its Impl. + static const time_zone::Impl& get(const time_zone& tz); + + // Clears the map of cached time zones. Primarily for use in benchmarks + // that gauge the performance of loading/parsing the time-zone data. + static void ClearTimeZoneMapTestOnly(); + + // The primary key is the time-zone ID (e.g., "America/New_York"). + const std::string& name() const { return name_; } + + // Breaks a time_point down to civil-time components in this time zone. + time_zone::absolute_lookup BreakTime( + const time_point<sys_seconds>& tp) const { + return zone_->BreakTime(tp); + } + + // Converts the civil-time components in this time zone into a time_point. + // That is, the opposite of BreakTime(). The requested civil time may be + // ambiguous or illegal due to a change of UTC offset. + time_zone::civil_lookup MakeTime(const civil_second& cs) const { + return zone_->MakeTime(cs); + } + + // Returns an implementation-specific description of this time zone. + std::string Description() const { return zone_->Description(); } + + // Finds the time of the next/previous offset change in this time zone. + // + // By definition, NextTransition(&tp) returns false when tp has its + // maximum value, and PrevTransition(&tp) returns false when tp has its + // mimimum value. If the zone has no transitions, the result will also + // be false no matter what the argument. + // + // Otherwise, when tp has its mimimum value, NextTransition(&tp) returns + // true and sets tp to the first recorded transition. Chains of calls + // to NextTransition()/PrevTransition() will eventually return false, + // but it is unspecified exactly when NextTransition(&tp) jumps to false, + // or what time is set by PrevTransition(&tp) for a very distant tp. + bool NextTransition(time_point<sys_seconds>* tp) const { + return zone_->NextTransition(tp); + } + bool PrevTransition(time_point<sys_seconds>* tp) const { + return zone_->PrevTransition(tp); + } + + private: + explicit Impl(const std::string& name); + static const Impl* UTCImpl(); + + const std::string name_; + std::unique_ptr<TimeZoneIf> zone_; +}; + +} // namespace cctz +} // namespace time_internal +} // namespace absl + +#endif // ABSL_TIME_INTERNAL_CCTZ_TIME_ZONE_IMPL_H_ |