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Diffstat (limited to 'third_party/abseil_cpp/absl/time/time.h')
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diff --git a/third_party/abseil_cpp/absl/time/time.h b/third_party/abseil_cpp/absl/time/time.h deleted file mode 100644 index 37f6131dd8..0000000000 --- a/third_party/abseil_cpp/absl/time/time.h +++ /dev/null @@ -1,1583 +0,0 @@ -// Copyright 2017 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. -// -// ----------------------------------------------------------------------------- -// File: time.h -// ----------------------------------------------------------------------------- -// -// This header file defines abstractions for computing with absolute points -// in time, durations of time, and formatting and parsing time within a given -// time zone. The following abstractions are defined: -// -// * `absl::Time` defines an absolute, specific instance in time -// * `absl::Duration` defines a signed, fixed-length span of time -// * `absl::TimeZone` defines geopolitical time zone regions (as collected -// within the IANA Time Zone database (https://www.iana.org/time-zones)). -// -// Note: Absolute times are distinct from civil times, which refer to the -// human-scale time commonly represented by `YYYY-MM-DD hh:mm:ss`. The mapping -// between absolute and civil times can be specified by use of time zones -// (`absl::TimeZone` within this API). That is: -// -// Civil Time = F(Absolute Time, Time Zone) -// Absolute Time = G(Civil Time, Time Zone) -// -// See civil_time.h for abstractions related to constructing and manipulating -// civil time. -// -// Example: -// -// absl::TimeZone nyc; -// // LoadTimeZone() may fail so it's always better to check for success. -// if (!absl::LoadTimeZone("America/New_York", &nyc)) { -// // handle error case -// } -// -// // My flight leaves NYC on Jan 2, 2017 at 03:04:05 -// absl::CivilSecond cs(2017, 1, 2, 3, 4, 5); -// absl::Time takeoff = absl::FromCivil(cs, nyc); -// -// absl::Duration flight_duration = absl::Hours(21) + absl::Minutes(35); -// absl::Time landing = takeoff + flight_duration; -// -// absl::TimeZone syd; -// if (!absl::LoadTimeZone("Australia/Sydney", &syd)) { -// // handle error case -// } -// std::string s = absl::FormatTime( -// "My flight will land in Sydney on %Y-%m-%d at %H:%M:%S", -// landing, syd); - -#ifndef ABSL_TIME_TIME_H_ -#define ABSL_TIME_TIME_H_ - -#if !defined(_MSC_VER) -#include <sys/time.h> -#else -// We don't include `winsock2.h` because it drags in `windows.h` and friends, -// and they define conflicting macros like OPAQUE, ERROR, and more. This has the -// potential to break Abseil users. -// -// Instead we only forward declare `timeval` and require Windows users include -// `winsock2.h` themselves. This is both inconsistent and troublesome, but so is -// including 'windows.h' so we are picking the lesser of two evils here. -struct timeval; -#endif -#include <chrono> // NOLINT(build/c++11) -#include <cmath> -#include <cstdint> -#include <ctime> -#include <ostream> -#include <string> -#include <type_traits> -#include <utility> - -#include "absl/base/macros.h" -#include "absl/strings/string_view.h" -#include "absl/time/civil_time.h" -#include "absl/time/internal/cctz/include/cctz/time_zone.h" - -namespace absl { -ABSL_NAMESPACE_BEGIN - -class Duration; // Defined below -class Time; // Defined below -class TimeZone; // Defined below - -namespace time_internal { -int64_t IDivDuration(bool satq, Duration num, Duration den, Duration* rem); -constexpr Time FromUnixDuration(Duration d); -constexpr Duration ToUnixDuration(Time t); -constexpr int64_t GetRepHi(Duration d); -constexpr uint32_t GetRepLo(Duration d); -constexpr Duration MakeDuration(int64_t hi, uint32_t lo); -constexpr Duration MakeDuration(int64_t hi, int64_t lo); -inline Duration MakePosDoubleDuration(double n); -constexpr int64_t kTicksPerNanosecond = 4; -constexpr int64_t kTicksPerSecond = 1000 * 1000 * 1000 * kTicksPerNanosecond; -template <std::intmax_t N> -constexpr Duration FromInt64(int64_t v, std::ratio<1, N>); -constexpr Duration FromInt64(int64_t v, std::ratio<60>); -constexpr Duration FromInt64(int64_t v, std::ratio<3600>); -template <typename T> -using EnableIfIntegral = typename std::enable_if< - std::is_integral<T>::value || std::is_enum<T>::value, int>::type; -template <typename T> -using EnableIfFloat = - typename std::enable_if<std::is_floating_point<T>::value, int>::type; -} // namespace time_internal - -// Duration -// -// The `absl::Duration` class represents a signed, fixed-length span of time. -// A `Duration` is generated using a unit-specific factory function, or is -// the result of subtracting one `absl::Time` from another. Durations behave -// like unit-safe integers and they support all the natural integer-like -// arithmetic operations. Arithmetic overflows and saturates at +/- infinity. -// `Duration` should be passed by value rather than const reference. -// -// Factory functions `Nanoseconds()`, `Microseconds()`, `Milliseconds()`, -// `Seconds()`, `Minutes()`, `Hours()` and `InfiniteDuration()` allow for -// creation of constexpr `Duration` values -// -// Examples: -// -// constexpr absl::Duration ten_ns = absl::Nanoseconds(10); -// constexpr absl::Duration min = absl::Minutes(1); -// constexpr absl::Duration hour = absl::Hours(1); -// absl::Duration dur = 60 * min; // dur == hour -// absl::Duration half_sec = absl::Milliseconds(500); -// absl::Duration quarter_sec = 0.25 * absl::Seconds(1); -// -// `Duration` values can be easily converted to an integral number of units -// using the division operator. -// -// Example: -// -// constexpr absl::Duration dur = absl::Milliseconds(1500); -// int64_t ns = dur / absl::Nanoseconds(1); // ns == 1500000000 -// int64_t ms = dur / absl::Milliseconds(1); // ms == 1500 -// int64_t sec = dur / absl::Seconds(1); // sec == 1 (subseconds truncated) -// int64_t min = dur / absl::Minutes(1); // min == 0 -// -// See the `IDivDuration()` and `FDivDuration()` functions below for details on -// how to access the fractional parts of the quotient. -// -// Alternatively, conversions can be performed using helpers such as -// `ToInt64Microseconds()` and `ToDoubleSeconds()`. -class Duration { - public: - // Value semantics. - constexpr Duration() : rep_hi_(0), rep_lo_(0) {} // zero-length duration - - // Copyable. -#if !defined(__clang__) && defined(_MSC_VER) && _MSC_VER < 1910 - // Explicitly defining the constexpr copy constructor avoids an MSVC bug. - constexpr Duration(const Duration& d) - : rep_hi_(d.rep_hi_), rep_lo_(d.rep_lo_) {} -#else - constexpr Duration(const Duration& d) = default; -#endif - Duration& operator=(const Duration& d) = default; - - // Compound assignment operators. - Duration& operator+=(Duration d); - Duration& operator-=(Duration d); - Duration& operator*=(int64_t r); - Duration& operator*=(double r); - Duration& operator/=(int64_t r); - Duration& operator/=(double r); - Duration& operator%=(Duration rhs); - - // Overloads that forward to either the int64_t or double overloads above. - // Integer operands must be representable as int64_t. - template <typename T> - Duration& operator*=(T r) { - int64_t x = r; - return *this *= x; - } - template <typename T> - Duration& operator/=(T r) { - int64_t x = r; - return *this /= x; - } - Duration& operator*=(float r) { return *this *= static_cast<double>(r); } - Duration& operator/=(float r) { return *this /= static_cast<double>(r); } - - template <typename H> - friend H AbslHashValue(H h, Duration d) { - return H::combine(std::move(h), d.rep_hi_, d.rep_lo_); - } - - private: - friend constexpr int64_t time_internal::GetRepHi(Duration d); - friend constexpr uint32_t time_internal::GetRepLo(Duration d); - friend constexpr Duration time_internal::MakeDuration(int64_t hi, - uint32_t lo); - constexpr Duration(int64_t hi, uint32_t lo) : rep_hi_(hi), rep_lo_(lo) {} - int64_t rep_hi_; - uint32_t rep_lo_; -}; - -// Relational Operators -constexpr bool operator<(Duration lhs, Duration rhs); -constexpr bool operator>(Duration lhs, Duration rhs) { return rhs < lhs; } -constexpr bool operator>=(Duration lhs, Duration rhs) { return !(lhs < rhs); } -constexpr bool operator<=(Duration lhs, Duration rhs) { return !(rhs < lhs); } -constexpr bool operator==(Duration lhs, Duration rhs); -constexpr bool operator!=(Duration lhs, Duration rhs) { return !(lhs == rhs); } - -// Additive Operators -constexpr Duration operator-(Duration d); -inline Duration operator+(Duration lhs, Duration rhs) { return lhs += rhs; } -inline Duration operator-(Duration lhs, Duration rhs) { return lhs -= rhs; } - -// Multiplicative Operators -// Integer operands must be representable as int64_t. -template <typename T> -Duration operator*(Duration lhs, T rhs) { - return lhs *= rhs; -} -template <typename T> -Duration operator*(T lhs, Duration rhs) { - return rhs *= lhs; -} -template <typename T> -Duration operator/(Duration lhs, T rhs) { - return lhs /= rhs; -} -inline int64_t operator/(Duration lhs, Duration rhs) { - return time_internal::IDivDuration(true, lhs, rhs, - &lhs); // trunc towards zero -} -inline Duration operator%(Duration lhs, Duration rhs) { return lhs %= rhs; } - -// IDivDuration() -// -// Divides a numerator `Duration` by a denominator `Duration`, returning the -// quotient and remainder. The remainder always has the same sign as the -// numerator. The returned quotient and remainder respect the identity: -// -// numerator = denominator * quotient + remainder -// -// Returned quotients are capped to the range of `int64_t`, with the difference -// spilling into the remainder to uphold the above identity. This means that the -// remainder returned could differ from the remainder returned by -// `Duration::operator%` for huge quotients. -// -// See also the notes on `InfiniteDuration()` below regarding the behavior of -// division involving zero and infinite durations. -// -// Example: -// -// constexpr absl::Duration a = -// absl::Seconds(std::numeric_limits<int64_t>::max()); // big -// constexpr absl::Duration b = absl::Nanoseconds(1); // small -// -// absl::Duration rem = a % b; -// // rem == absl::ZeroDuration() -// -// // Here, q would overflow int64_t, so rem accounts for the difference. -// int64_t q = absl::IDivDuration(a, b, &rem); -// // q == std::numeric_limits<int64_t>::max(), rem == a - b * q -inline int64_t IDivDuration(Duration num, Duration den, Duration* rem) { - return time_internal::IDivDuration(true, num, den, - rem); // trunc towards zero -} - -// FDivDuration() -// -// Divides a `Duration` numerator into a fractional number of units of a -// `Duration` denominator. -// -// See also the notes on `InfiniteDuration()` below regarding the behavior of -// division involving zero and infinite durations. -// -// Example: -// -// double d = absl::FDivDuration(absl::Milliseconds(1500), absl::Seconds(1)); -// // d == 1.5 -double FDivDuration(Duration num, Duration den); - -// ZeroDuration() -// -// Returns a zero-length duration. This function behaves just like the default -// constructor, but the name helps make the semantics clear at call sites. -constexpr Duration ZeroDuration() { return Duration(); } - -// AbsDuration() -// -// Returns the absolute value of a duration. -inline Duration AbsDuration(Duration d) { - return (d < ZeroDuration()) ? -d : d; -} - -// Trunc() -// -// Truncates a duration (toward zero) to a multiple of a non-zero unit. -// -// Example: -// -// absl::Duration d = absl::Nanoseconds(123456789); -// absl::Duration a = absl::Trunc(d, absl::Microseconds(1)); // 123456us -Duration Trunc(Duration d, Duration unit); - -// Floor() -// -// Floors a duration using the passed duration unit to its largest value not -// greater than the duration. -// -// Example: -// -// absl::Duration d = absl::Nanoseconds(123456789); -// absl::Duration b = absl::Floor(d, absl::Microseconds(1)); // 123456us -Duration Floor(Duration d, Duration unit); - -// Ceil() -// -// Returns the ceiling of a duration using the passed duration unit to its -// smallest value not less than the duration. -// -// Example: -// -// absl::Duration d = absl::Nanoseconds(123456789); -// absl::Duration c = absl::Ceil(d, absl::Microseconds(1)); // 123457us -Duration Ceil(Duration d, Duration unit); - -// InfiniteDuration() -// -// Returns an infinite `Duration`. To get a `Duration` representing negative -// infinity, use `-InfiniteDuration()`. -// -// Duration arithmetic overflows to +/- infinity and saturates. In general, -// arithmetic with `Duration` infinities is similar to IEEE 754 infinities -// except where IEEE 754 NaN would be involved, in which case +/- -// `InfiniteDuration()` is used in place of a "nan" Duration. -// -// Examples: -// -// constexpr absl::Duration inf = absl::InfiniteDuration(); -// const absl::Duration d = ... any finite duration ... -// -// inf == inf + inf -// inf == inf + d -// inf == inf - inf -// -inf == d - inf -// -// inf == d * 1e100 -// inf == inf / 2 -// 0 == d / inf -// INT64_MAX == inf / d -// -// d < inf -// -inf < d -// -// // Division by zero returns infinity, or INT64_MIN/MAX where appropriate. -// inf == d / 0 -// INT64_MAX == d / absl::ZeroDuration() -// -// The examples involving the `/` operator above also apply to `IDivDuration()` -// and `FDivDuration()`. -constexpr Duration InfiniteDuration(); - -// Nanoseconds() -// Microseconds() -// Milliseconds() -// Seconds() -// Minutes() -// Hours() -// -// Factory functions for constructing `Duration` values from an integral number -// of the unit indicated by the factory function's name. The number must be -// representable as int64_t. -// -// NOTE: no "Days()" factory function exists because "a day" is ambiguous. -// Civil days are not always 24 hours long, and a 24-hour duration often does -// not correspond with a civil day. If a 24-hour duration is needed, use -// `absl::Hours(24)`. If you actually want a civil day, use absl::CivilDay -// from civil_time.h. -// -// Example: -// -// absl::Duration a = absl::Seconds(60); -// absl::Duration b = absl::Minutes(1); // b == a -constexpr Duration Nanoseconds(int64_t n); -constexpr Duration Microseconds(int64_t n); -constexpr Duration Milliseconds(int64_t n); -constexpr Duration Seconds(int64_t n); -constexpr Duration Minutes(int64_t n); -constexpr Duration Hours(int64_t n); - -// Factory overloads for constructing `Duration` values from a floating-point -// number of the unit indicated by the factory function's name. These functions -// exist for convenience, but they are not as efficient as the integral -// factories, which should be preferred. -// -// Example: -// -// auto a = absl::Seconds(1.5); // OK -// auto b = absl::Milliseconds(1500); // BETTER -template <typename T, time_internal::EnableIfFloat<T> = 0> -Duration Nanoseconds(T n) { - return n * Nanoseconds(1); -} -template <typename T, time_internal::EnableIfFloat<T> = 0> -Duration Microseconds(T n) { - return n * Microseconds(1); -} -template <typename T, time_internal::EnableIfFloat<T> = 0> -Duration Milliseconds(T n) { - return n * Milliseconds(1); -} -template <typename T, time_internal::EnableIfFloat<T> = 0> -Duration Seconds(T n) { - if (n >= 0) { // Note: `NaN >= 0` is false. - if (n >= static_cast<T>((std::numeric_limits<int64_t>::max)())) { - return InfiniteDuration(); - } - return time_internal::MakePosDoubleDuration(n); - } else { - if (std::isnan(n)) - return std::signbit(n) ? -InfiniteDuration() : InfiniteDuration(); - if (n <= (std::numeric_limits<int64_t>::min)()) return -InfiniteDuration(); - return -time_internal::MakePosDoubleDuration(-n); - } -} -template <typename T, time_internal::EnableIfFloat<T> = 0> -Duration Minutes(T n) { - return n * Minutes(1); -} -template <typename T, time_internal::EnableIfFloat<T> = 0> -Duration Hours(T n) { - return n * Hours(1); -} - -// ToInt64Nanoseconds() -// ToInt64Microseconds() -// ToInt64Milliseconds() -// ToInt64Seconds() -// ToInt64Minutes() -// ToInt64Hours() -// -// Helper functions that convert a Duration to an integral count of the -// indicated unit. These functions are shorthand for the `IDivDuration()` -// function above; see its documentation for details about overflow, etc. -// -// Example: -// -// absl::Duration d = absl::Milliseconds(1500); -// int64_t isec = absl::ToInt64Seconds(d); // isec == 1 -int64_t ToInt64Nanoseconds(Duration d); -int64_t ToInt64Microseconds(Duration d); -int64_t ToInt64Milliseconds(Duration d); -int64_t ToInt64Seconds(Duration d); -int64_t ToInt64Minutes(Duration d); -int64_t ToInt64Hours(Duration d); - -// ToDoubleNanoSeconds() -// ToDoubleMicroseconds() -// ToDoubleMilliseconds() -// ToDoubleSeconds() -// ToDoubleMinutes() -// ToDoubleHours() -// -// Helper functions that convert a Duration to a floating point count of the -// indicated unit. These functions are shorthand for the `FDivDuration()` -// function above; see its documentation for details about overflow, etc. -// -// Example: -// -// absl::Duration d = absl::Milliseconds(1500); -// double dsec = absl::ToDoubleSeconds(d); // dsec == 1.5 -double ToDoubleNanoseconds(Duration d); -double ToDoubleMicroseconds(Duration d); -double ToDoubleMilliseconds(Duration d); -double ToDoubleSeconds(Duration d); -double ToDoubleMinutes(Duration d); -double ToDoubleHours(Duration d); - -// FromChrono() -// -// Converts any of the pre-defined std::chrono durations to an absl::Duration. -// -// Example: -// -// std::chrono::milliseconds ms(123); -// absl::Duration d = absl::FromChrono(ms); -constexpr Duration FromChrono(const std::chrono::nanoseconds& d); -constexpr Duration FromChrono(const std::chrono::microseconds& d); -constexpr Duration FromChrono(const std::chrono::milliseconds& d); -constexpr Duration FromChrono(const std::chrono::seconds& d); -constexpr Duration FromChrono(const std::chrono::minutes& d); -constexpr Duration FromChrono(const std::chrono::hours& d); - -// ToChronoNanoseconds() -// ToChronoMicroseconds() -// ToChronoMilliseconds() -// ToChronoSeconds() -// ToChronoMinutes() -// ToChronoHours() -// -// Converts an absl::Duration to any of the pre-defined std::chrono durations. -// If overflow would occur, the returned value will saturate at the min/max -// chrono duration value instead. -// -// Example: -// -// absl::Duration d = absl::Microseconds(123); -// auto x = absl::ToChronoMicroseconds(d); -// auto y = absl::ToChronoNanoseconds(d); // x == y -// auto z = absl::ToChronoSeconds(absl::InfiniteDuration()); -// // z == std::chrono::seconds::max() -std::chrono::nanoseconds ToChronoNanoseconds(Duration d); -std::chrono::microseconds ToChronoMicroseconds(Duration d); -std::chrono::milliseconds ToChronoMilliseconds(Duration d); -std::chrono::seconds ToChronoSeconds(Duration d); -std::chrono::minutes ToChronoMinutes(Duration d); -std::chrono::hours ToChronoHours(Duration d); - -// FormatDuration() -// -// Returns a string representing the duration in the form "72h3m0.5s". -// Returns "inf" or "-inf" for +/- `InfiniteDuration()`. -std::string FormatDuration(Duration d); - -// Output stream operator. -inline std::ostream& operator<<(std::ostream& os, Duration d) { - return os << FormatDuration(d); -} - -// ParseDuration() -// -// Parses a duration string consisting of a possibly signed sequence of -// decimal numbers, each with an optional fractional part and a unit -// suffix. The valid suffixes are "ns", "us" "ms", "s", "m", and "h". -// Simple examples include "300ms", "-1.5h", and "2h45m". Parses "0" as -// `ZeroDuration()`. Parses "inf" and "-inf" as +/- `InfiniteDuration()`. -bool ParseDuration(absl::string_view dur_string, Duration* d); - -// Support for flag values of type Duration. Duration flags must be specified -// in a format that is valid input for absl::ParseDuration(). -bool AbslParseFlag(absl::string_view text, Duration* dst, std::string* error); -std::string AbslUnparseFlag(Duration d); -ABSL_DEPRECATED("Use AbslParseFlag() instead.") -bool ParseFlag(const std::string& text, Duration* dst, std::string* error); -ABSL_DEPRECATED("Use AbslUnparseFlag() instead.") -std::string UnparseFlag(Duration d); - -// Time -// -// An `absl::Time` represents a specific instant in time. Arithmetic operators -// are provided for naturally expressing time calculations. Instances are -// created using `absl::Now()` and the `absl::From*()` factory functions that -// accept the gamut of other time representations. Formatting and parsing -// functions are provided for conversion to and from strings. `absl::Time` -// should be passed by value rather than const reference. -// -// `absl::Time` assumes there are 60 seconds in a minute, which means the -// underlying time scales must be "smeared" to eliminate leap seconds. -// See https://developers.google.com/time/smear. -// -// Even though `absl::Time` supports a wide range of timestamps, exercise -// caution when using values in the distant past. `absl::Time` uses the -// Proleptic Gregorian calendar, which extends the Gregorian calendar backward -// to dates before its introduction in 1582. -// See https://en.wikipedia.org/wiki/Proleptic_Gregorian_calendar -// for more information. Use the ICU calendar classes to convert a date in -// some other calendar (http://userguide.icu-project.org/datetime/calendar). -// -// Similarly, standardized time zones are a reasonably recent innovation, with -// the Greenwich prime meridian being established in 1884. The TZ database -// itself does not profess accurate offsets for timestamps prior to 1970. The -// breakdown of future timestamps is subject to the whim of regional -// governments. -// -// The `absl::Time` class represents an instant in time as a count of clock -// ticks of some granularity (resolution) from some starting point (epoch). -// -// `absl::Time` uses a resolution that is high enough to avoid loss in -// precision, and a range that is wide enough to avoid overflow, when -// converting between tick counts in most Google time scales (i.e., resolution -// of at least one nanosecond, and range +/-100 billion years). Conversions -// between the time scales are performed by truncating (towards negative -// infinity) to the nearest representable point. -// -// Examples: -// -// absl::Time t1 = ...; -// absl::Time t2 = t1 + absl::Minutes(2); -// absl::Duration d = t2 - t1; // == absl::Minutes(2) -// -class Time { - public: - // Value semantics. - - // Returns the Unix epoch. However, those reading your code may not know - // or expect the Unix epoch as the default value, so make your code more - // readable by explicitly initializing all instances before use. - // - // Example: - // absl::Time t = absl::UnixEpoch(); - // absl::Time t = absl::Now(); - // absl::Time t = absl::TimeFromTimeval(tv); - // absl::Time t = absl::InfinitePast(); - constexpr Time() = default; - - // Copyable. - constexpr Time(const Time& t) = default; - Time& operator=(const Time& t) = default; - - // Assignment operators. - Time& operator+=(Duration d) { - rep_ += d; - return *this; - } - Time& operator-=(Duration d) { - rep_ -= d; - return *this; - } - - // Time::Breakdown - // - // The calendar and wall-clock (aka "civil time") components of an - // `absl::Time` in a certain `absl::TimeZone`. This struct is not - // intended to represent an instant in time. So, rather than passing - // a `Time::Breakdown` to a function, pass an `absl::Time` and an - // `absl::TimeZone`. - // - // Deprecated. Use `absl::TimeZone::CivilInfo`. - struct - Breakdown { - int64_t year; // year (e.g., 2013) - int month; // month of year [1:12] - int day; // day of month [1:31] - int hour; // hour of day [0:23] - int minute; // minute of hour [0:59] - int second; // second of minute [0:59] - Duration subsecond; // [Seconds(0):Seconds(1)) if finite - int weekday; // 1==Mon, ..., 7=Sun - int yearday; // day of year [1:366] - - // Note: The following fields exist for backward compatibility - // with older APIs. Accessing these fields directly is a sign of - // imprudent logic in the calling code. Modern time-related code - // should only access this data indirectly by way of FormatTime(). - // These fields are undefined for InfiniteFuture() and InfinitePast(). - int offset; // seconds east of UTC - bool is_dst; // is offset non-standard? - const char* zone_abbr; // time-zone abbreviation (e.g., "PST") - }; - - // Time::In() - // - // Returns the breakdown of this instant in the given TimeZone. - // - // Deprecated. Use `absl::TimeZone::At(Time)`. - Breakdown In(TimeZone tz) const; - - template <typename H> - friend H AbslHashValue(H h, Time t) { - return H::combine(std::move(h), t.rep_); - } - - private: - friend constexpr Time time_internal::FromUnixDuration(Duration d); - friend constexpr Duration time_internal::ToUnixDuration(Time t); - friend constexpr bool operator<(Time lhs, Time rhs); - friend constexpr bool operator==(Time lhs, Time rhs); - friend Duration operator-(Time lhs, Time rhs); - friend constexpr Time UniversalEpoch(); - friend constexpr Time InfiniteFuture(); - friend constexpr Time InfinitePast(); - constexpr explicit Time(Duration rep) : rep_(rep) {} - Duration rep_; -}; - -// Relational Operators -constexpr bool operator<(Time lhs, Time rhs) { return lhs.rep_ < rhs.rep_; } -constexpr bool operator>(Time lhs, Time rhs) { return rhs < lhs; } -constexpr bool operator>=(Time lhs, Time rhs) { return !(lhs < rhs); } -constexpr bool operator<=(Time lhs, Time rhs) { return !(rhs < lhs); } -constexpr bool operator==(Time lhs, Time rhs) { return lhs.rep_ == rhs.rep_; } -constexpr bool operator!=(Time lhs, Time rhs) { return !(lhs == rhs); } - -// Additive Operators -inline Time operator+(Time lhs, Duration rhs) { return lhs += rhs; } -inline Time operator+(Duration lhs, Time rhs) { return rhs += lhs; } -inline Time operator-(Time lhs, Duration rhs) { return lhs -= rhs; } -inline Duration operator-(Time lhs, Time rhs) { return lhs.rep_ - rhs.rep_; } - -// UnixEpoch() -// -// Returns the `absl::Time` representing "1970-01-01 00:00:00.0 +0000". -constexpr Time UnixEpoch() { return Time(); } - -// UniversalEpoch() -// -// Returns the `absl::Time` representing "0001-01-01 00:00:00.0 +0000", the -// epoch of the ICU Universal Time Scale. -constexpr Time UniversalEpoch() { - // 719162 is the number of days from 0001-01-01 to 1970-01-01, - // assuming the Gregorian calendar. - return Time(time_internal::MakeDuration(-24 * 719162 * int64_t{3600}, 0U)); -} - -// InfiniteFuture() -// -// Returns an `absl::Time` that is infinitely far in the future. -constexpr Time InfiniteFuture() { - return Time( - time_internal::MakeDuration((std::numeric_limits<int64_t>::max)(), ~0U)); -} - -// InfinitePast() -// -// Returns an `absl::Time` that is infinitely far in the past. -constexpr Time InfinitePast() { - return Time( - time_internal::MakeDuration((std::numeric_limits<int64_t>::min)(), ~0U)); -} - -// FromUnixNanos() -// FromUnixMicros() -// FromUnixMillis() -// FromUnixSeconds() -// FromTimeT() -// FromUDate() -// FromUniversal() -// -// Creates an `absl::Time` from a variety of other representations. -constexpr Time FromUnixNanos(int64_t ns); -constexpr Time FromUnixMicros(int64_t us); -constexpr Time FromUnixMillis(int64_t ms); -constexpr Time FromUnixSeconds(int64_t s); -constexpr Time FromTimeT(time_t t); -Time FromUDate(double udate); -Time FromUniversal(int64_t universal); - -// ToUnixNanos() -// ToUnixMicros() -// ToUnixMillis() -// ToUnixSeconds() -// ToTimeT() -// ToUDate() -// ToUniversal() -// -// Converts an `absl::Time` to a variety of other representations. Note that -// these operations round down toward negative infinity where necessary to -// adjust to the resolution of the result type. Beware of possible time_t -// over/underflow in ToTime{T,val,spec}() on 32-bit platforms. -int64_t ToUnixNanos(Time t); -int64_t ToUnixMicros(Time t); -int64_t ToUnixMillis(Time t); -int64_t ToUnixSeconds(Time t); -time_t ToTimeT(Time t); -double ToUDate(Time t); -int64_t ToUniversal(Time t); - -// DurationFromTimespec() -// DurationFromTimeval() -// ToTimespec() -// ToTimeval() -// TimeFromTimespec() -// TimeFromTimeval() -// ToTimespec() -// ToTimeval() -// -// Some APIs use a timespec or a timeval as a Duration (e.g., nanosleep(2) -// and select(2)), while others use them as a Time (e.g. clock_gettime(2) -// and gettimeofday(2)), so conversion functions are provided for both cases. -// The "to timespec/val" direction is easily handled via overloading, but -// for "from timespec/val" the desired type is part of the function name. -Duration DurationFromTimespec(timespec ts); -Duration DurationFromTimeval(timeval tv); -timespec ToTimespec(Duration d); -timeval ToTimeval(Duration d); -Time TimeFromTimespec(timespec ts); -Time TimeFromTimeval(timeval tv); -timespec ToTimespec(Time t); -timeval ToTimeval(Time t); - -// FromChrono() -// -// Converts a std::chrono::system_clock::time_point to an absl::Time. -// -// Example: -// -// auto tp = std::chrono::system_clock::from_time_t(123); -// absl::Time t = absl::FromChrono(tp); -// // t == absl::FromTimeT(123) -Time FromChrono(const std::chrono::system_clock::time_point& tp); - -// ToChronoTime() -// -// Converts an absl::Time to a std::chrono::system_clock::time_point. If -// overflow would occur, the returned value will saturate at the min/max time -// point value instead. -// -// Example: -// -// absl::Time t = absl::FromTimeT(123); -// auto tp = absl::ToChronoTime(t); -// // tp == std::chrono::system_clock::from_time_t(123); -std::chrono::system_clock::time_point ToChronoTime(Time); - -// Support for flag values of type Time. Time flags must be specified in a -// format that matches absl::RFC3339_full. For example: -// -// --start_time=2016-01-02T03:04:05.678+08:00 -// -// Note: A UTC offset (or 'Z' indicating a zero-offset from UTC) is required. -// -// Additionally, if you'd like to specify a time as a count of -// seconds/milliseconds/etc from the Unix epoch, use an absl::Duration flag -// and add that duration to absl::UnixEpoch() to get an absl::Time. -bool AbslParseFlag(absl::string_view text, Time* t, std::string* error); -std::string AbslUnparseFlag(Time t); -ABSL_DEPRECATED("Use AbslParseFlag() instead.") -bool ParseFlag(const std::string& text, Time* t, std::string* error); -ABSL_DEPRECATED("Use AbslUnparseFlag() instead.") -std::string UnparseFlag(Time t); - -// TimeZone -// -// The `absl::TimeZone` is an opaque, small, value-type class representing a -// geo-political region within which particular rules are used for converting -// between absolute and civil times (see https://git.io/v59Ly). `absl::TimeZone` -// values are named using the TZ identifiers from the IANA Time Zone Database, -// such as "America/Los_Angeles" or "Australia/Sydney". `absl::TimeZone` values -// are created from factory functions such as `absl::LoadTimeZone()`. Note: -// strings like "PST" and "EDT" are not valid TZ identifiers. Prefer to pass by -// value rather than const reference. -// -// For more on the fundamental concepts of time zones, absolute times, and civil -// times, see https://github.com/google/cctz#fundamental-concepts -// -// Examples: -// -// absl::TimeZone utc = absl::UTCTimeZone(); -// absl::TimeZone pst = absl::FixedTimeZone(-8 * 60 * 60); -// absl::TimeZone loc = absl::LocalTimeZone(); -// absl::TimeZone lax; -// if (!absl::LoadTimeZone("America/Los_Angeles", &lax)) { -// // handle error case -// } -// -// See also: -// - https://github.com/google/cctz -// - https://www.iana.org/time-zones -// - https://en.wikipedia.org/wiki/Zoneinfo -class TimeZone { - public: - explicit TimeZone(time_internal::cctz::time_zone tz) : cz_(tz) {} - TimeZone() = default; // UTC, but prefer UTCTimeZone() to be explicit. - - // Copyable. - TimeZone(const TimeZone&) = default; - TimeZone& operator=(const TimeZone&) = default; - - explicit operator time_internal::cctz::time_zone() const { return cz_; } - - std::string name() const { return cz_.name(); } - - // TimeZone::CivilInfo - // - // Information about the civil time corresponding to an absolute time. - // This struct is not intended to represent an instant in time. So, rather - // than passing a `TimeZone::CivilInfo` to a function, pass an `absl::Time` - // and an `absl::TimeZone`. - struct CivilInfo { - CivilSecond cs; - Duration subsecond; - - // Note: The following fields exist for backward compatibility - // with older APIs. Accessing these fields directly is a sign of - // imprudent logic in the calling code. Modern time-related code - // should only access this data indirectly by way of FormatTime(). - // These fields are undefined for InfiniteFuture() and InfinitePast(). - int offset; // seconds east of UTC - bool is_dst; // is offset non-standard? - const char* zone_abbr; // time-zone abbreviation (e.g., "PST") - }; - - // TimeZone::At(Time) - // - // Returns the civil time for this TimeZone at a certain `absl::Time`. - // If the input time is infinite, the output civil second will be set to - // CivilSecond::max() or min(), and the subsecond will be infinite. - // - // Example: - // - // const auto epoch = lax.At(absl::UnixEpoch()); - // // epoch.cs == 1969-12-31 16:00:00 - // // epoch.subsecond == absl::ZeroDuration() - // // epoch.offset == -28800 - // // epoch.is_dst == false - // // epoch.abbr == "PST" - CivilInfo At(Time t) const; - - // TimeZone::TimeInfo - // - // Information about the absolute times corresponding to a civil time. - // (Subseconds must be handled separately.) - // - // It is possible for a caller to pass a civil-time value that does - // not represent an actual or unique instant in time (due to a shift - // in UTC offset in the TimeZone, which results in a discontinuity in - // the civil-time components). For example, a daylight-saving-time - // transition skips or repeats civil times---in the United States, - // March 13, 2011 02:15 never occurred, while November 6, 2011 01:15 - // occurred twice---so requests for such times are not well-defined. - // To account for these possibilities, `absl::TimeZone::TimeInfo` is - // richer than just a single `absl::Time`. - struct TimeInfo { - enum CivilKind { - UNIQUE, // the civil time was singular (pre == trans == post) - SKIPPED, // the civil time did not exist (pre >= trans > post) - REPEATED, // the civil time was ambiguous (pre < trans <= post) - } kind; - Time pre; // time calculated using the pre-transition offset - Time trans; // when the civil-time discontinuity occurred - Time post; // time calculated using the post-transition offset - }; - - // TimeZone::At(CivilSecond) - // - // Returns an `absl::TimeInfo` containing the absolute time(s) for this - // TimeZone at an `absl::CivilSecond`. When the civil time is skipped or - // repeated, returns times calculated using the pre-transition and post- - // transition UTC offsets, plus the transition time itself. - // - // Examples: - // - // // A unique civil time - // const auto jan01 = lax.At(absl::CivilSecond(2011, 1, 1, 0, 0, 0)); - // // jan01.kind == TimeZone::TimeInfo::UNIQUE - // // jan01.pre is 2011-01-01 00:00:00 -0800 - // // jan01.trans is 2011-01-01 00:00:00 -0800 - // // jan01.post is 2011-01-01 00:00:00 -0800 - // - // // A Spring DST transition, when there is a gap in civil time - // const auto mar13 = lax.At(absl::CivilSecond(2011, 3, 13, 2, 15, 0)); - // // mar13.kind == TimeZone::TimeInfo::SKIPPED - // // mar13.pre is 2011-03-13 03:15:00 -0700 - // // mar13.trans is 2011-03-13 03:00:00 -0700 - // // mar13.post is 2011-03-13 01:15:00 -0800 - // - // // A Fall DST transition, when civil times are repeated - // const auto nov06 = lax.At(absl::CivilSecond(2011, 11, 6, 1, 15, 0)); - // // nov06.kind == TimeZone::TimeInfo::REPEATED - // // nov06.pre is 2011-11-06 01:15:00 -0700 - // // nov06.trans is 2011-11-06 01:00:00 -0800 - // // nov06.post is 2011-11-06 01:15:00 -0800 - TimeInfo At(CivilSecond ct) const; - - // TimeZone::NextTransition() - // TimeZone::PrevTransition() - // - // Finds the time of the next/previous offset change in this time zone. - // - // By definition, `NextTransition(t, &trans)` returns false when `t` is - // `InfiniteFuture()`, and `PrevTransition(t, &trans)` returns false - // when `t` is `InfinitePast()`. If the zone has no transitions, the - // result will also be false no matter what the argument. - // - // Otherwise, when `t` is `InfinitePast()`, `NextTransition(t, &trans)` - // returns true and sets `trans` to the first recorded transition. Chains - // of calls to `NextTransition()/PrevTransition()` will eventually return - // false, but it is unspecified exactly when `NextTransition(t, &trans)` - // jumps to false, or what time is set by `PrevTransition(t, &trans)` for - // a very distant `t`. - // - // Note: Enumeration of time-zone transitions is for informational purposes - // only. Modern time-related code should not care about when offset changes - // occur. - // - // Example: - // absl::TimeZone nyc; - // if (!absl::LoadTimeZone("America/New_York", &nyc)) { ... } - // const auto now = absl::Now(); - // auto t = absl::InfinitePast(); - // absl::TimeZone::CivilTransition trans; - // while (t <= now && nyc.NextTransition(t, &trans)) { - // // transition: trans.from -> trans.to - // t = nyc.At(trans.to).trans; - // } - struct CivilTransition { - CivilSecond from; // the civil time we jump from - CivilSecond to; // the civil time we jump to - }; - bool NextTransition(Time t, CivilTransition* trans) const; - bool PrevTransition(Time t, CivilTransition* trans) const; - - template <typename H> - friend H AbslHashValue(H h, TimeZone tz) { - return H::combine(std::move(h), tz.cz_); - } - - private: - friend bool operator==(TimeZone a, TimeZone b) { return a.cz_ == b.cz_; } - friend bool operator!=(TimeZone a, TimeZone b) { return a.cz_ != b.cz_; } - friend std::ostream& operator<<(std::ostream& os, TimeZone tz) { - return os << tz.name(); - } - - time_internal::cctz::time_zone cz_; -}; - -// LoadTimeZone() -// -// Loads the named zone. May perform I/O on the initial load of the named -// zone. If the name is invalid, or some other kind of error occurs, returns -// `false` and `*tz` is set to the UTC time zone. -inline bool LoadTimeZone(absl::string_view name, TimeZone* tz) { - if (name == "localtime") { - *tz = TimeZone(time_internal::cctz::local_time_zone()); - return true; - } - time_internal::cctz::time_zone cz; - const bool b = time_internal::cctz::load_time_zone(std::string(name), &cz); - *tz = TimeZone(cz); - return b; -} - -// FixedTimeZone() -// -// Returns a TimeZone that is a fixed offset (seconds east) from UTC. -// Note: If the absolute value of the offset is greater than 24 hours -// you'll get UTC (i.e., no offset) instead. -inline TimeZone FixedTimeZone(int seconds) { - return TimeZone( - time_internal::cctz::fixed_time_zone(std::chrono::seconds(seconds))); -} - -// UTCTimeZone() -// -// Convenience method returning the UTC time zone. -inline TimeZone UTCTimeZone() { - return TimeZone(time_internal::cctz::utc_time_zone()); -} - -// LocalTimeZone() -// -// Convenience method returning the local time zone, or UTC if there is -// no configured local zone. Warning: Be wary of using LocalTimeZone(), -// and particularly so in a server process, as the zone configured for the -// local machine should be irrelevant. Prefer an explicit zone name. -inline TimeZone LocalTimeZone() { - return TimeZone(time_internal::cctz::local_time_zone()); -} - -// ToCivilSecond() -// ToCivilMinute() -// ToCivilHour() -// ToCivilDay() -// ToCivilMonth() -// ToCivilYear() -// -// Helpers for TimeZone::At(Time) to return particularly aligned civil times. -// -// Example: -// -// absl::Time t = ...; -// absl::TimeZone tz = ...; -// const auto cd = absl::ToCivilDay(t, tz); -inline CivilSecond ToCivilSecond(Time t, TimeZone tz) { - return tz.At(t).cs; // already a CivilSecond -} -inline CivilMinute ToCivilMinute(Time t, TimeZone tz) { - return CivilMinute(tz.At(t).cs); -} -inline CivilHour ToCivilHour(Time t, TimeZone tz) { - return CivilHour(tz.At(t).cs); -} -inline CivilDay ToCivilDay(Time t, TimeZone tz) { - return CivilDay(tz.At(t).cs); -} -inline CivilMonth ToCivilMonth(Time t, TimeZone tz) { - return CivilMonth(tz.At(t).cs); -} -inline CivilYear ToCivilYear(Time t, TimeZone tz) { - return CivilYear(tz.At(t).cs); -} - -// FromCivil() -// -// Helper for TimeZone::At(CivilSecond) that provides "order-preserving -// semantics." If the civil time maps to a unique time, that time is -// returned. If the civil time is repeated in the given time zone, the -// time using the pre-transition offset is returned. Otherwise, the -// civil time is skipped in the given time zone, and the transition time -// is returned. This means that for any two civil times, ct1 and ct2, -// (ct1 < ct2) => (FromCivil(ct1) <= FromCivil(ct2)), the equal case -// being when two non-existent civil times map to the same transition time. -// -// Note: Accepts civil times of any alignment. -inline Time FromCivil(CivilSecond ct, TimeZone tz) { - const auto ti = tz.At(ct); - if (ti.kind == TimeZone::TimeInfo::SKIPPED) return ti.trans; - return ti.pre; -} - -// TimeConversion -// -// An `absl::TimeConversion` represents the conversion of year, month, day, -// hour, minute, and second values (i.e., a civil time), in a particular -// `absl::TimeZone`, to a time instant (an absolute time), as returned by -// `absl::ConvertDateTime()`. Legacy version of `absl::TimeZone::TimeInfo`. -// -// Deprecated. Use `absl::TimeZone::TimeInfo`. -struct - TimeConversion { - Time pre; // time calculated using the pre-transition offset - Time trans; // when the civil-time discontinuity occurred - Time post; // time calculated using the post-transition offset - - enum Kind { - UNIQUE, // the civil time was singular (pre == trans == post) - SKIPPED, // the civil time did not exist - REPEATED, // the civil time was ambiguous - }; - Kind kind; - - bool normalized; // input values were outside their valid ranges -}; - -// ConvertDateTime() -// -// Legacy version of `absl::TimeZone::At(absl::CivilSecond)` that takes -// the civil time as six, separate values (YMDHMS). -// -// The input month, day, hour, minute, and second values can be outside -// of their valid ranges, in which case they will be "normalized" during -// the conversion. -// -// Example: -// -// // "October 32" normalizes to "November 1". -// absl::TimeConversion tc = -// absl::ConvertDateTime(2013, 10, 32, 8, 30, 0, lax); -// // tc.kind == TimeConversion::UNIQUE && tc.normalized == true -// // absl::ToCivilDay(tc.pre, tz).month() == 11 -// // absl::ToCivilDay(tc.pre, tz).day() == 1 -// -// Deprecated. Use `absl::TimeZone::At(CivilSecond)`. -TimeConversion ConvertDateTime(int64_t year, int mon, int day, int hour, - int min, int sec, TimeZone tz); - -// FromDateTime() -// -// A convenience wrapper for `absl::ConvertDateTime()` that simply returns -// the "pre" `absl::Time`. That is, the unique result, or the instant that -// is correct using the pre-transition offset (as if the transition never -// happened). -// -// Example: -// -// absl::Time t = absl::FromDateTime(2017, 9, 26, 9, 30, 0, lax); -// // t = 2017-09-26 09:30:00 -0700 -// -// Deprecated. Use `absl::FromCivil(CivilSecond, TimeZone)`. Note that the -// behavior of `FromCivil()` differs from `FromDateTime()` for skipped civil -// times. If you care about that see `absl::TimeZone::At(absl::CivilSecond)`. -inline Time FromDateTime(int64_t year, int mon, int day, int hour, - int min, int sec, TimeZone tz) { - return ConvertDateTime(year, mon, day, hour, min, sec, tz).pre; -} - -// FromTM() -// -// Converts the `tm_year`, `tm_mon`, `tm_mday`, `tm_hour`, `tm_min`, and -// `tm_sec` fields to an `absl::Time` using the given time zone. See ctime(3) -// for a description of the expected values of the tm fields. If the indicated -// time instant is not unique (see `absl::TimeZone::At(absl::CivilSecond)` -// above), the `tm_isdst` field is consulted to select the desired instant -// (`tm_isdst` > 0 means DST, `tm_isdst` == 0 means no DST, `tm_isdst` < 0 -// means use the post-transition offset). -Time FromTM(const struct tm& tm, TimeZone tz); - -// ToTM() -// -// Converts the given `absl::Time` to a struct tm using the given time zone. -// See ctime(3) for a description of the values of the tm fields. -struct tm ToTM(Time t, TimeZone tz); - -// RFC3339_full -// RFC3339_sec -// -// FormatTime()/ParseTime() format specifiers for RFC3339 date/time strings, -// with trailing zeros trimmed or with fractional seconds omitted altogether. -// -// Note that RFC3339_sec[] matches an ISO 8601 extended format for date and -// time with UTC offset. Also note the use of "%Y": RFC3339 mandates that -// years have exactly four digits, but we allow them to take their natural -// width. -ABSL_DLL extern const char RFC3339_full[]; // %Y-%m-%d%ET%H:%M:%E*S%Ez -ABSL_DLL extern const char RFC3339_sec[]; // %Y-%m-%d%ET%H:%M:%S%Ez - -// RFC1123_full -// RFC1123_no_wday -// -// FormatTime()/ParseTime() format specifiers for RFC1123 date/time strings. -ABSL_DLL extern const char RFC1123_full[]; // %a, %d %b %E4Y %H:%M:%S %z -ABSL_DLL extern const char RFC1123_no_wday[]; // %d %b %E4Y %H:%M:%S %z - -// FormatTime() -// -// Formats the given `absl::Time` in the `absl::TimeZone` according to the -// provided format string. Uses strftime()-like formatting options, with -// the following extensions: -// -// - %Ez - RFC3339-compatible numeric UTC offset (+hh:mm or -hh:mm) -// - %E*z - Full-resolution numeric UTC offset (+hh:mm:ss or -hh:mm:ss) -// - %E#S - Seconds with # digits of fractional precision -// - %E*S - Seconds with full fractional precision (a literal '*') -// - %E#f - Fractional seconds with # digits of precision -// - %E*f - Fractional seconds with full precision (a literal '*') -// - %E4Y - Four-character years (-999 ... -001, 0000, 0001 ... 9999) -// - %ET - The RFC3339 "date-time" separator "T" -// -// Note that %E0S behaves like %S, and %E0f produces no characters. In -// contrast %E*f always produces at least one digit, which may be '0'. -// -// Note that %Y produces as many characters as it takes to fully render the -// year. A year outside of [-999:9999] when formatted with %E4Y will produce -// more than four characters, just like %Y. -// -// We recommend that format strings include the UTC offset (%z, %Ez, or %E*z) -// so that the result uniquely identifies a time instant. -// -// Example: -// -// absl::CivilSecond cs(2013, 1, 2, 3, 4, 5); -// absl::Time t = absl::FromCivil(cs, lax); -// std::string f = absl::FormatTime("%H:%M:%S", t, lax); // "03:04:05" -// f = absl::FormatTime("%H:%M:%E3S", t, lax); // "03:04:05.000" -// -// Note: If the given `absl::Time` is `absl::InfiniteFuture()`, the returned -// string will be exactly "infinite-future". If the given `absl::Time` is -// `absl::InfinitePast()`, the returned string will be exactly "infinite-past". -// In both cases the given format string and `absl::TimeZone` are ignored. -// -std::string FormatTime(absl::string_view format, Time t, TimeZone tz); - -// Convenience functions that format the given time using the RFC3339_full -// format. The first overload uses the provided TimeZone, while the second -// uses LocalTimeZone(). -std::string FormatTime(Time t, TimeZone tz); -std::string FormatTime(Time t); - -// Output stream operator. -inline std::ostream& operator<<(std::ostream& os, Time t) { - return os << FormatTime(t); -} - -// ParseTime() -// -// Parses an input string according to the provided format string and -// returns the corresponding `absl::Time`. Uses strftime()-like formatting -// options, with the same extensions as FormatTime(), but with the -// exceptions that %E#S is interpreted as %E*S, and %E#f as %E*f. %Ez -// and %E*z also accept the same inputs, which (along with %z) includes -// 'z' and 'Z' as synonyms for +00:00. %ET accepts either 'T' or 't'. -// -// %Y consumes as many numeric characters as it can, so the matching data -// should always be terminated with a non-numeric. %E4Y always consumes -// exactly four characters, including any sign. -// -// Unspecified fields are taken from the default date and time of ... -// -// "1970-01-01 00:00:00.0 +0000" -// -// For example, parsing a string of "15:45" (%H:%M) will return an absl::Time -// that represents "1970-01-01 15:45:00.0 +0000". -// -// Note that since ParseTime() returns time instants, it makes the most sense -// to parse fully-specified date/time strings that include a UTC offset (%z, -// %Ez, or %E*z). -// -// Note also that `absl::ParseTime()` only heeds the fields year, month, day, -// hour, minute, (fractional) second, and UTC offset. Other fields, like -// weekday (%a or %A), while parsed for syntactic validity, are ignored -// in the conversion. -// -// Date and time fields that are out-of-range will be treated as errors -// rather than normalizing them like `absl::CivilSecond` does. For example, -// it is an error to parse the date "Oct 32, 2013" because 32 is out of range. -// -// A leap second of ":60" is normalized to ":00" of the following minute -// with fractional seconds discarded. The following table shows how the -// given seconds and subseconds will be parsed: -// -// "59.x" -> 59.x // exact -// "60.x" -> 00.0 // normalized -// "00.x" -> 00.x // exact -// -// Errors are indicated by returning false and assigning an error message -// to the "err" out param if it is non-null. -// -// Note: If the input string is exactly "infinite-future", the returned -// `absl::Time` will be `absl::InfiniteFuture()` and `true` will be returned. -// If the input string is "infinite-past", the returned `absl::Time` will be -// `absl::InfinitePast()` and `true` will be returned. -// -bool ParseTime(absl::string_view format, absl::string_view input, Time* time, - std::string* err); - -// Like ParseTime() above, but if the format string does not contain a UTC -// offset specification (%z/%Ez/%E*z) then the input is interpreted in the -// given TimeZone. This means that the input, by itself, does not identify a -// unique instant. Being time-zone dependent, it also admits the possibility -// of ambiguity or non-existence, in which case the "pre" time (as defined -// by TimeZone::TimeInfo) is returned. For these reasons we recommend that -// all date/time strings include a UTC offset so they're context independent. -bool ParseTime(absl::string_view format, absl::string_view input, TimeZone tz, - Time* time, std::string* err); - -// ============================================================================ -// Implementation Details Follow -// ============================================================================ - -namespace time_internal { - -// Creates a Duration with a given representation. -// REQUIRES: hi,lo is a valid representation of a Duration as specified -// in time/duration.cc. -constexpr Duration MakeDuration(int64_t hi, uint32_t lo = 0) { - return Duration(hi, lo); -} - -constexpr Duration MakeDuration(int64_t hi, int64_t lo) { - return MakeDuration(hi, static_cast<uint32_t>(lo)); -} - -// Make a Duration value from a floating-point number, as long as that number -// is in the range [ 0 .. numeric_limits<int64_t>::max ), that is, as long as -// it's positive and can be converted to int64_t without risk of UB. -inline Duration MakePosDoubleDuration(double n) { - const int64_t int_secs = static_cast<int64_t>(n); - const uint32_t ticks = static_cast<uint32_t>( - (n - static_cast<double>(int_secs)) * kTicksPerSecond + 0.5); - return ticks < kTicksPerSecond - ? MakeDuration(int_secs, ticks) - : MakeDuration(int_secs + 1, ticks - kTicksPerSecond); -} - -// Creates a normalized Duration from an almost-normalized (sec,ticks) -// pair. sec may be positive or negative. ticks must be in the range -// -kTicksPerSecond < *ticks < kTicksPerSecond. If ticks is negative it -// will be normalized to a positive value in the resulting Duration. -constexpr Duration MakeNormalizedDuration(int64_t sec, int64_t ticks) { - return (ticks < 0) ? MakeDuration(sec - 1, ticks + kTicksPerSecond) - : MakeDuration(sec, ticks); -} - -// Provide access to the Duration representation. -constexpr int64_t GetRepHi(Duration d) { return d.rep_hi_; } -constexpr uint32_t GetRepLo(Duration d) { return d.rep_lo_; } - -// Returns true iff d is positive or negative infinity. -constexpr bool IsInfiniteDuration(Duration d) { return GetRepLo(d) == ~0U; } - -// Returns an infinite Duration with the opposite sign. -// REQUIRES: IsInfiniteDuration(d) -constexpr Duration OppositeInfinity(Duration d) { - return GetRepHi(d) < 0 - ? MakeDuration((std::numeric_limits<int64_t>::max)(), ~0U) - : MakeDuration((std::numeric_limits<int64_t>::min)(), ~0U); -} - -// Returns (-n)-1 (equivalently -(n+1)) without avoidable overflow. -constexpr int64_t NegateAndSubtractOne(int64_t n) { - // Note: Good compilers will optimize this expression to ~n when using - // a two's-complement representation (which is required for int64_t). - return (n < 0) ? -(n + 1) : (-n) - 1; -} - -// Map between a Time and a Duration since the Unix epoch. Note that these -// functions depend on the above mentioned choice of the Unix epoch for the -// Time representation (and both need to be Time friends). Without this -// knowledge, we would need to add-in/subtract-out UnixEpoch() respectively. -constexpr Time FromUnixDuration(Duration d) { return Time(d); } -constexpr Duration ToUnixDuration(Time t) { return t.rep_; } - -template <std::intmax_t N> -constexpr Duration FromInt64(int64_t v, std::ratio<1, N>) { - static_assert(0 < N && N <= 1000 * 1000 * 1000, "Unsupported ratio"); - // Subsecond ratios cannot overflow. - return MakeNormalizedDuration( - v / N, v % N * kTicksPerNanosecond * 1000 * 1000 * 1000 / N); -} -constexpr Duration FromInt64(int64_t v, std::ratio<60>) { - return (v <= (std::numeric_limits<int64_t>::max)() / 60 && - v >= (std::numeric_limits<int64_t>::min)() / 60) - ? MakeDuration(v * 60) - : v > 0 ? InfiniteDuration() : -InfiniteDuration(); -} -constexpr Duration FromInt64(int64_t v, std::ratio<3600>) { - return (v <= (std::numeric_limits<int64_t>::max)() / 3600 && - v >= (std::numeric_limits<int64_t>::min)() / 3600) - ? MakeDuration(v * 3600) - : v > 0 ? InfiniteDuration() : -InfiniteDuration(); -} - -// IsValidRep64<T>(0) is true if the expression `int64_t{std::declval<T>()}` is -// valid. That is, if a T can be assigned to an int64_t without narrowing. -template <typename T> -constexpr auto IsValidRep64(int) -> decltype(int64_t{std::declval<T>()} == 0) { - return true; -} -template <typename T> -constexpr auto IsValidRep64(char) -> bool { - return false; -} - -// Converts a std::chrono::duration to an absl::Duration. -template <typename Rep, typename Period> -constexpr Duration FromChrono(const std::chrono::duration<Rep, Period>& d) { - static_assert(IsValidRep64<Rep>(0), "duration::rep is invalid"); - return FromInt64(int64_t{d.count()}, Period{}); -} - -template <typename Ratio> -int64_t ToInt64(Duration d, Ratio) { - // Note: This may be used on MSVC, which may have a system_clock period of - // std::ratio<1, 10 * 1000 * 1000> - return ToInt64Seconds(d * Ratio::den / Ratio::num); -} -// Fastpath implementations for the 6 common duration units. -inline int64_t ToInt64(Duration d, std::nano) { - return ToInt64Nanoseconds(d); -} -inline int64_t ToInt64(Duration d, std::micro) { - return ToInt64Microseconds(d); -} -inline int64_t ToInt64(Duration d, std::milli) { - return ToInt64Milliseconds(d); -} -inline int64_t ToInt64(Duration d, std::ratio<1>) { - return ToInt64Seconds(d); -} -inline int64_t ToInt64(Duration d, std::ratio<60>) { - return ToInt64Minutes(d); -} -inline int64_t ToInt64(Duration d, std::ratio<3600>) { - return ToInt64Hours(d); -} - -// Converts an absl::Duration to a chrono duration of type T. -template <typename T> -T ToChronoDuration(Duration d) { - using Rep = typename T::rep; - using Period = typename T::period; - static_assert(IsValidRep64<Rep>(0), "duration::rep is invalid"); - if (time_internal::IsInfiniteDuration(d)) - return d < ZeroDuration() ? (T::min)() : (T::max)(); - const auto v = ToInt64(d, Period{}); - if (v > (std::numeric_limits<Rep>::max)()) return (T::max)(); - if (v < (std::numeric_limits<Rep>::min)()) return (T::min)(); - return T{v}; -} - -} // namespace time_internal - -constexpr Duration Nanoseconds(int64_t n) { - return time_internal::FromInt64(n, std::nano{}); -} -constexpr Duration Microseconds(int64_t n) { - return time_internal::FromInt64(n, std::micro{}); -} -constexpr Duration Milliseconds(int64_t n) { - return time_internal::FromInt64(n, std::milli{}); -} -constexpr Duration Seconds(int64_t n) { - return time_internal::FromInt64(n, std::ratio<1>{}); -} -constexpr Duration Minutes(int64_t n) { - return time_internal::FromInt64(n, std::ratio<60>{}); -} -constexpr Duration Hours(int64_t n) { - return time_internal::FromInt64(n, std::ratio<3600>{}); -} - -constexpr bool operator<(Duration lhs, Duration rhs) { - return time_internal::GetRepHi(lhs) != time_internal::GetRepHi(rhs) - ? time_internal::GetRepHi(lhs) < time_internal::GetRepHi(rhs) - : time_internal::GetRepHi(lhs) == - (std::numeric_limits<int64_t>::min)() - ? time_internal::GetRepLo(lhs) + 1 < - time_internal::GetRepLo(rhs) + 1 - : time_internal::GetRepLo(lhs) < - time_internal::GetRepLo(rhs); -} - -constexpr bool operator==(Duration lhs, Duration rhs) { - return time_internal::GetRepHi(lhs) == time_internal::GetRepHi(rhs) && - time_internal::GetRepLo(lhs) == time_internal::GetRepLo(rhs); -} - -constexpr Duration operator-(Duration d) { - // This is a little interesting because of the special cases. - // - // If rep_lo_ is zero, we have it easy; it's safe to negate rep_hi_, we're - // dealing with an integral number of seconds, and the only special case is - // the maximum negative finite duration, which can't be negated. - // - // Infinities stay infinite, and just change direction. - // - // Finally we're in the case where rep_lo_ is non-zero, and we can borrow - // a second's worth of ticks and avoid overflow (as negating int64_t-min + 1 - // is safe). - return time_internal::GetRepLo(d) == 0 - ? time_internal::GetRepHi(d) == - (std::numeric_limits<int64_t>::min)() - ? InfiniteDuration() - : time_internal::MakeDuration(-time_internal::GetRepHi(d)) - : time_internal::IsInfiniteDuration(d) - ? time_internal::OppositeInfinity(d) - : time_internal::MakeDuration( - time_internal::NegateAndSubtractOne( - time_internal::GetRepHi(d)), - time_internal::kTicksPerSecond - - time_internal::GetRepLo(d)); -} - -constexpr Duration InfiniteDuration() { - return time_internal::MakeDuration((std::numeric_limits<int64_t>::max)(), - ~0U); -} - -constexpr Duration FromChrono(const std::chrono::nanoseconds& d) { - return time_internal::FromChrono(d); -} -constexpr Duration FromChrono(const std::chrono::microseconds& d) { - return time_internal::FromChrono(d); -} -constexpr Duration FromChrono(const std::chrono::milliseconds& d) { - return time_internal::FromChrono(d); -} -constexpr Duration FromChrono(const std::chrono::seconds& d) { - return time_internal::FromChrono(d); -} -constexpr Duration FromChrono(const std::chrono::minutes& d) { - return time_internal::FromChrono(d); -} -constexpr Duration FromChrono(const std::chrono::hours& d) { - return time_internal::FromChrono(d); -} - -constexpr Time FromUnixNanos(int64_t ns) { - return time_internal::FromUnixDuration(Nanoseconds(ns)); -} - -constexpr Time FromUnixMicros(int64_t us) { - return time_internal::FromUnixDuration(Microseconds(us)); -} - -constexpr Time FromUnixMillis(int64_t ms) { - return time_internal::FromUnixDuration(Milliseconds(ms)); -} - -constexpr Time FromUnixSeconds(int64_t s) { - return time_internal::FromUnixDuration(Seconds(s)); -} - -constexpr Time FromTimeT(time_t t) { - return time_internal::FromUnixDuration(Seconds(t)); -} - -ABSL_NAMESPACE_END -} // namespace absl - -#endif // ABSL_TIME_TIME_H_ |