time_zone_impl.h (3482B)
1 // Copyright 2016 Google Inc. All Rights Reserved. 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // https://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 #ifndef ABSL_TIME_INTERNAL_CCTZ_TIME_ZONE_IMPL_H_ 16 #define ABSL_TIME_INTERNAL_CCTZ_TIME_ZONE_IMPL_H_ 17 18 #include <memory> 19 #include <string> 20 21 #include "absl/base/config.h" 22 #include "absl/time/internal/cctz/include/cctz/civil_time.h" 23 #include "absl/time/internal/cctz/include/cctz/time_zone.h" 24 #include "absl/time/internal/cctz/src/time_zone_if.h" 25 #include "absl/time/internal/cctz/src/time_zone_info.h" 26 27 namespace absl { 28 ABSL_NAMESPACE_BEGIN 29 namespace time_internal { 30 namespace cctz { 31 32 // time_zone::Impl is the internal object referenced by a cctz::time_zone. 33 class time_zone::Impl { 34 public: 35 // The UTC time zone. Also used for other time zones that fail to load. 36 static time_zone UTC(); 37 38 // Load a named time zone. Returns false if the name is invalid, or if 39 // some other kind of error occurs. Note that loading "UTC" never fails. 40 static bool LoadTimeZone(const std::string& name, time_zone* tz); 41 42 // Clears the map of cached time zones. Primarily for use in benchmarks 43 // that gauge the performance of loading/parsing the time-zone data. 44 static void ClearTimeZoneMapTestOnly(); 45 46 // The primary key is the time-zone ID (e.g., "America/New_York"). 47 const std::string& Name() const { 48 // TODO: It would nice if the zoneinfo data included the zone name. 49 return name_; 50 } 51 52 // Breaks a time_point down to civil-time components in this time zone. 53 time_zone::absolute_lookup BreakTime(const time_point<seconds>& tp) const { 54 return zone_->BreakTime(tp); 55 } 56 57 // Converts the civil-time components in this time zone into a time_point. 58 // That is, the opposite of BreakTime(). The requested civil time may be 59 // ambiguous or illegal due to a change of UTC offset. 60 time_zone::civil_lookup MakeTime(const civil_second& cs) const { 61 return zone_->MakeTime(cs); 62 } 63 64 // Finds the time of the next/previous offset change in this time zone. 65 bool NextTransition(const time_point<seconds>& tp, 66 time_zone::civil_transition* trans) const { 67 return zone_->NextTransition(tp, trans); 68 } 69 bool PrevTransition(const time_point<seconds>& tp, 70 time_zone::civil_transition* trans) const { 71 return zone_->PrevTransition(tp, trans); 72 } 73 74 // Returns an implementation-defined version string for this time zone. 75 std::string Version() const { return zone_->Version(); } 76 77 // Returns an implementation-defined description of this time zone. 78 std::string Description() const { return zone_->Description(); } 79 80 private: 81 Impl(); 82 explicit Impl(const std::string& name); 83 Impl(const Impl&) = delete; 84 Impl& operator=(const Impl&) = delete; 85 86 static const Impl* UTCImpl(); 87 88 const std::string name_; 89 std::unique_ptr<TimeZoneIf> zone_; 90 }; 91 92 } // namespace cctz 93 } // namespace time_internal 94 ABSL_NAMESPACE_END 95 } // namespace absl 96 97 #endif // ABSL_TIME_INTERNAL_CCTZ_TIME_ZONE_IMPL_H_