diff options
Diffstat (limited to 'third_party/abseil_cpp/absl/time/civil_time.cc')
-rw-r--r-- | third_party/abseil_cpp/absl/time/civil_time.cc | 175 |
1 files changed, 175 insertions, 0 deletions
diff --git a/third_party/abseil_cpp/absl/time/civil_time.cc b/third_party/abseil_cpp/absl/time/civil_time.cc new file mode 100644 index 000000000000..c4202c7399ae --- /dev/null +++ b/third_party/abseil_cpp/absl/time/civil_time.cc @@ -0,0 +1,175 @@ +// Copyright 2018 The Abseil Authors. +// +// 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 +// +// https://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. + +#include "absl/time/civil_time.h" + +#include <cstdlib> +#include <string> + +#include "absl/strings/str_cat.h" +#include "absl/time/time.h" + +namespace absl { +ABSL_NAMESPACE_BEGIN + +namespace { + +// Since a civil time has a larger year range than absl::Time (64-bit years vs +// 64-bit seconds, respectively) we normalize years to roughly +/- 400 years +// around the year 2400, which will produce an equivalent year in a range that +// absl::Time can handle. +inline civil_year_t NormalizeYear(civil_year_t year) { + return 2400 + year % 400; +} + +// Formats the given CivilSecond according to the given format. +std::string FormatYearAnd(string_view fmt, CivilSecond cs) { + const CivilSecond ncs(NormalizeYear(cs.year()), cs.month(), cs.day(), + cs.hour(), cs.minute(), cs.second()); + const TimeZone utc = UTCTimeZone(); + // TODO(absl-team): Avoid conversion of fmt string. + return StrCat(cs.year(), + FormatTime(std::string(fmt), FromCivil(ncs, utc), utc)); +} + +template <typename CivilT> +bool ParseYearAnd(string_view fmt, string_view s, CivilT* c) { + // Civil times support a larger year range than absl::Time, so we need to + // parse the year separately, normalize it, then use absl::ParseTime on the + // normalized string. + const std::string ss = std::string(s); // TODO(absl-team): Avoid conversion. + const char* const np = ss.c_str(); + char* endp; + errno = 0; + const civil_year_t y = + std::strtoll(np, &endp, 10); // NOLINT(runtime/deprecated_fn) + if (endp == np || errno == ERANGE) return false; + const std::string norm = StrCat(NormalizeYear(y), endp); + + const TimeZone utc = UTCTimeZone(); + Time t; + if (ParseTime(StrCat("%Y", fmt), norm, utc, &t, nullptr)) { + const auto cs = ToCivilSecond(t, utc); + *c = CivilT(y, cs.month(), cs.day(), cs.hour(), cs.minute(), cs.second()); + return true; + } + + return false; +} + +// Tries to parse the type as a CivilT1, but then assigns the result to the +// argument of type CivilT2. +template <typename CivilT1, typename CivilT2> +bool ParseAs(string_view s, CivilT2* c) { + CivilT1 t1; + if (ParseCivilTime(s, &t1)) { + *c = CivilT2(t1); + return true; + } + return false; +} + +template <typename CivilT> +bool ParseLenient(string_view s, CivilT* c) { + // A fastpath for when the given string data parses exactly into the given + // type T (e.g., s="YYYY-MM-DD" and CivilT=CivilDay). + if (ParseCivilTime(s, c)) return true; + // Try parsing as each of the 6 types, trying the most common types first + // (based on csearch results). + if (ParseAs<CivilDay>(s, c)) return true; + if (ParseAs<CivilSecond>(s, c)) return true; + if (ParseAs<CivilHour>(s, c)) return true; + if (ParseAs<CivilMonth>(s, c)) return true; + if (ParseAs<CivilMinute>(s, c)) return true; + if (ParseAs<CivilYear>(s, c)) return true; + return false; +} +} // namespace + +std::string FormatCivilTime(CivilSecond c) { + return FormatYearAnd("-%m-%dT%H:%M:%S", c); +} +std::string FormatCivilTime(CivilMinute c) { + return FormatYearAnd("-%m-%dT%H:%M", c); +} +std::string FormatCivilTime(CivilHour c) { + return FormatYearAnd("-%m-%dT%H", c); +} +std::string FormatCivilTime(CivilDay c) { return FormatYearAnd("-%m-%d", c); } +std::string FormatCivilTime(CivilMonth c) { return FormatYearAnd("-%m", c); } +std::string FormatCivilTime(CivilYear c) { return FormatYearAnd("", c); } + +bool ParseCivilTime(string_view s, CivilSecond* c) { + return ParseYearAnd("-%m-%dT%H:%M:%S", s, c); +} +bool ParseCivilTime(string_view s, CivilMinute* c) { + return ParseYearAnd("-%m-%dT%H:%M", s, c); +} +bool ParseCivilTime(string_view s, CivilHour* c) { + return ParseYearAnd("-%m-%dT%H", s, c); +} +bool ParseCivilTime(string_view s, CivilDay* c) { + return ParseYearAnd("-%m-%d", s, c); +} +bool ParseCivilTime(string_view s, CivilMonth* c) { + return ParseYearAnd("-%m", s, c); +} +bool ParseCivilTime(string_view s, CivilYear* c) { + return ParseYearAnd("", s, c); +} + +bool ParseLenientCivilTime(string_view s, CivilSecond* c) { + return ParseLenient(s, c); +} +bool ParseLenientCivilTime(string_view s, CivilMinute* c) { + return ParseLenient(s, c); +} +bool ParseLenientCivilTime(string_view s, CivilHour* c) { + return ParseLenient(s, c); +} +bool ParseLenientCivilTime(string_view s, CivilDay* c) { + return ParseLenient(s, c); +} +bool ParseLenientCivilTime(string_view s, CivilMonth* c) { + return ParseLenient(s, c); +} +bool ParseLenientCivilTime(string_view s, CivilYear* c) { + return ParseLenient(s, c); +} + +namespace time_internal { + +std::ostream& operator<<(std::ostream& os, CivilYear y) { + return os << FormatCivilTime(y); +} +std::ostream& operator<<(std::ostream& os, CivilMonth m) { + return os << FormatCivilTime(m); +} +std::ostream& operator<<(std::ostream& os, CivilDay d) { + return os << FormatCivilTime(d); +} +std::ostream& operator<<(std::ostream& os, CivilHour h) { + return os << FormatCivilTime(h); +} +std::ostream& operator<<(std::ostream& os, CivilMinute m) { + return os << FormatCivilTime(m); +} +std::ostream& operator<<(std::ostream& os, CivilSecond s) { + return os << FormatCivilTime(s); +} + +} // namespace time_internal + +ABSL_NAMESPACE_END +} // namespace absl |