diff options
Diffstat (limited to 'lib/stdlib/src/calendar.erl')
| -rw-r--r-- | lib/stdlib/src/calendar.erl | 246 |
1 files changed, 229 insertions, 17 deletions
diff --git a/lib/stdlib/src/calendar.erl b/lib/stdlib/src/calendar.erl index 55a0cfc9a1..3a8fe2211b 100644 --- a/lib/stdlib/src/calendar.erl +++ b/lib/stdlib/src/calendar.erl @@ -1,7 +1,7 @@ %% %% %CopyrightBegin% %% -%% Copyright Ericsson AB 1996-2016. All Rights Reserved. +%% Copyright Ericsson AB 1996-2019. 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. @@ -39,8 +39,14 @@ now_to_datetime/1, % = now_to_universal_time/1 now_to_local_time/1, now_to_universal_time/1, + rfc3339_to_system_time/1, + rfc3339_to_system_time/2, seconds_to_daystime/1, seconds_to_time/1, + system_time_to_local_time/2, + system_time_to_universal_time/2, + system_time_to_rfc3339/1, + system_time_to_rfc3339/2, time_difference/2, time_to_seconds/1, universal_time/0, @@ -55,10 +61,13 @@ -define(SECONDS_PER_DAY, 86400). -define(DAYS_PER_YEAR, 365). -define(DAYS_PER_LEAP_YEAR, 366). --define(DAYS_PER_4YEARS, 1461). --define(DAYS_PER_100YEARS, 36524). --define(DAYS_PER_400YEARS, 146097). +%% -define(DAYS_PER_4YEARS, 1461). +%% -define(DAYS_PER_100YEARS, 36524). +%% -define(DAYS_PER_400YEARS, 146097). -define(DAYS_FROM_0_TO_1970, 719528). +-define(DAYS_FROM_0_TO_10000, 2932897). +-define(SECONDS_FROM_0_TO_1970, (?DAYS_FROM_0_TO_1970*?SECONDS_PER_DAY)). +-define(SECONDS_FROM_0_TO_10000, (?DAYS_FROM_0_TO_10000*?SECONDS_PER_DAY)). %%---------------------------------------------------------------------- %% Types @@ -83,6 +92,13 @@ -type datetime1970() :: {{year1970(),month(),day()},time()}. -type yearweeknum() :: {year(),weeknum()}. +-type rfc3339_string() :: [byte(), ...]. +%% By design 'native' is not supported: +-type rfc3339_time_unit() :: 'microsecond' + | 'millisecond' + | 'nanosecond' + | 'second'. + %%---------------------------------------------------------------------- %% All dates are according the the Gregorian calendar. In this module @@ -309,8 +325,7 @@ local_time_to_universal_time_dst(DateTime) -> -spec now_to_datetime(Now) -> datetime1970() when Now :: erlang:timestamp(). now_to_datetime({MSec, Sec, _uSec}) -> - Sec0 = MSec*1000000 + Sec + ?DAYS_FROM_0_TO_1970*?SECONDS_PER_DAY, - gregorian_seconds_to_datetime(Sec0). + system_time_to_datetime(MSec*1000000 + Sec). -spec now_to_universal_time(Now) -> datetime1970() when Now :: erlang:timestamp(). @@ -328,6 +343,37 @@ now_to_local_time({MSec, Sec, _uSec}) -> erlang:universaltime_to_localtime( now_to_universal_time({MSec, Sec, _uSec})). +-spec rfc3339_to_system_time(DateTimeString) -> integer() when + DateTimeString :: rfc3339_string(). + +rfc3339_to_system_time(DateTimeString) -> + rfc3339_to_system_time(DateTimeString, []). + +-spec rfc3339_to_system_time(DateTimeString, Options) -> integer() when + DateTimeString :: rfc3339_string(), + Options :: [Option], + Option :: {'unit', rfc3339_time_unit()}. + +rfc3339_to_system_time(DateTimeString, Options) -> + Unit = proplists:get_value(unit, Options, second), + %% _T is the character separating the date and the time: + [Y1, Y2, Y3, Y4, $-, Mon1, Mon2, $-, D1, D2, _T, + H1, H2, $:, Min1, Min2, $:, S1, S2 | TimeStr] = DateTimeString, + Hour = list_to_integer([H1, H2]), + Min = list_to_integer([Min1, Min2]), + Sec = list_to_integer([S1, S2]), + Year = list_to_integer([Y1, Y2, Y3, Y4]), + Month = list_to_integer([Mon1, Mon2]), + Day = list_to_integer([D1, D2]), + DateTime = {{Year, Month, Day}, {Hour, Min, Sec}}, + IsFractionChar = fun(C) -> C >= $0 andalso C =< $9 orelse C =:= $. end, + {FractionStr, UtcOffset} = lists:splitwith(IsFractionChar, TimeStr), + Time = datetime_to_system_time(DateTime), + Secs = Time - offset_adjustment(Time, second, UtcOffset), + check(DateTimeString, Options, Secs), + ScaledEpoch = erlang:convert_time_unit(Secs, second, Unit), + ScaledEpoch + copy_sign(fraction(Unit, FractionStr), ScaledEpoch). + %% seconds_to_daystime(Secs) = {Days, {Hour, Minute, Second}} @@ -363,6 +409,56 @@ seconds_to_time(Secs) when Secs >= 0, Secs < ?SECONDS_PER_DAY -> Second = Secs1 rem ?SECONDS_PER_MINUTE, {Hour, Minute, Second}. +-spec system_time_to_local_time(Time, TimeUnit) -> datetime() when + Time :: integer(), + TimeUnit :: erlang:time_unit(). + +system_time_to_local_time(Time, TimeUnit) -> + UniversalDate = system_time_to_universal_time(Time, TimeUnit), + erlang:universaltime_to_localtime(UniversalDate). + +-spec system_time_to_universal_time(Time, TimeUnit) -> datetime() when + Time :: integer(), + TimeUnit :: erlang:time_unit(). + +system_time_to_universal_time(Time, TimeUnit) -> + Secs = erlang:convert_time_unit(Time, TimeUnit, second), + system_time_to_datetime(Secs). + +-spec system_time_to_rfc3339(Time) -> DateTimeString when + Time :: integer(), + DateTimeString :: rfc3339_string(). + +system_time_to_rfc3339(Time) -> + system_time_to_rfc3339(Time, []). + +-type offset() :: [byte()] | (Time :: integer()). +-spec system_time_to_rfc3339(Time, Options) -> DateTimeString when + Time :: integer(), % Since Epoch + Options :: [Option], + Option :: {'offset', offset()} + | {'time_designator', byte()} + | {'unit', rfc3339_time_unit()}, + DateTimeString :: rfc3339_string(). + +system_time_to_rfc3339(Time, Options) -> + Unit = proplists:get_value(unit, Options, second), + OffsetOption = proplists:get_value(offset, Options, ""), + T = proplists:get_value(time_designator, Options, $T), + AdjustmentSecs = offset_adjustment(Time, Unit, OffsetOption), + Offset = offset(OffsetOption, AdjustmentSecs), + Adjustment = erlang:convert_time_unit(AdjustmentSecs, second, Unit), + AdjustedTime = Time + Adjustment, + Factor = factor(Unit), + Secs = AdjustedTime div Factor, + check(Time, Options, Secs), + DateTime = system_time_to_datetime(Secs), + {{Year, Month, Day}, {Hour, Min, Sec}} = DateTime, + FractionStr = fraction_str(Factor, AdjustedTime), + L = [pad4(Year), "-", pad2(Month), "-", pad2(Day), [T], + pad2(Hour), ":", pad2(Min), ":", pad2(Sec), FractionStr, Offset], + lists:append(L). + %% time_difference(T1, T2) = Tdiff %% %% Returns the difference between two {Date, Time} structures. @@ -438,24 +534,41 @@ valid_date({Y, M, D}) -> %% day_to_year(DayOfEpoch) = {Year, DayOfYear} %% -%% The idea here is to first guess a year, and then adjust. Although -%% the implementation is recursive, at most 1 or 2 recursive steps +%% The idea here is to first set the upper and lower bounds for a year, +%% and then adjust a range by interpolation search. Although complexity +%% of the algorithm is log(log(n)), at most 1 or 2 recursive steps %% are taken. -%% If DayOfEpoch is very large, we need far more than 1 or 2 iterations, -%% since we just subtract a yearful of days at a time until we're there. %% -spec day_to_year(non_neg_integer()) -> {year(), day_of_year()}. day_to_year(DayOfEpoch) when DayOfEpoch >= 0 -> - Y0 = DayOfEpoch div ?DAYS_PER_YEAR, - {Y1, D1} = dty(Y0, DayOfEpoch, dy(Y0)), + YMax = DayOfEpoch div ?DAYS_PER_YEAR, + YMin = DayOfEpoch div ?DAYS_PER_LEAP_YEAR, + {Y1, D1} = dty(YMin, YMax, DayOfEpoch, dy(YMin), dy(YMax)), {Y1, DayOfEpoch - D1}. --spec dty(year(), non_neg_integer(), non_neg_integer()) -> +-spec dty(year(), year(), non_neg_integer(), non_neg_integer(), + non_neg_integer()) -> {year(), non_neg_integer()}. -dty(Y, D1, D2) when D1 < D2 -> - dty(Y-1, D1, dy(Y-1)); -dty(Y, _D1, D2) -> - {Y, D2}. +dty(Min, Max, _D1, DMin, _DMax) when Min == Max -> + {Min, DMin}; +dty(Min, Max, D1, DMin, DMax) -> + Diff = Max - Min, + Mid = Min + (Diff * (D1 - DMin)) div (DMax - DMin), + MidLength = + case is_leap_year(Mid) of + true -> ?DAYS_PER_LEAP_YEAR; + false -> ?DAYS_PER_YEAR + end, + case dy(Mid) of + D2 when D1 < D2 -> + NewMax = Mid - 1, + dty(Min, NewMax, D1, DMin, dy(NewMax)); + D2 when D1 - D2 >= MidLength -> + NewMin = Mid + 1, + dty(NewMin, Max, D1, dy(NewMin), DMax); + D2 -> + {Mid, D2} + end. %% %% The Gregorian days of the iso week 01 day 1 for a given year. @@ -550,3 +663,102 @@ df(Year, _) -> true -> 1; false -> 0 end. + +check(_Arg, _Options, Secs) when Secs >= - ?SECONDS_FROM_0_TO_1970, + Secs < ?SECONDS_FROM_0_TO_10000 -> + ok; +check(Arg, Options, _Secs) -> + erlang:error({badarg, [Arg, Options]}). + +datetime_to_system_time(DateTime) -> + datetime_to_gregorian_seconds(DateTime) - ?SECONDS_FROM_0_TO_1970. + +system_time_to_datetime(Seconds) -> + gregorian_seconds_to_datetime(Seconds + ?SECONDS_FROM_0_TO_1970). + +offset(OffsetOption, Secs0) when OffsetOption =:= ""; + is_integer(OffsetOption) -> + Sign = case Secs0 < 0 of + true -> $-; + false -> $+ + end, + Secs = abs(Secs0), + Hour = Secs div 3600, + Min = (Secs rem 3600) div 60, + [Sign | lists:append([pad2(Hour), ":", pad2(Min)])]; +offset(OffsetOption, _Secs) -> + OffsetOption. + +offset_adjustment(Time, Unit, OffsetString) when is_list(OffsetString) -> + offset_string_adjustment(Time, Unit, OffsetString); +offset_adjustment(_Time, Unit, Offset) when is_integer(Offset) -> + erlang:convert_time_unit(Offset, Unit, second). + +offset_string_adjustment(Time, Unit, "") -> + local_offset(Time, Unit); +offset_string_adjustment(_Time, _Unit, "Z") -> + 0; +offset_string_adjustment(_Time, _Unit, "z") -> + 0; +offset_string_adjustment(_Time, _Unit, Tz) -> + [Sign, H1, H2, $:, M1, M2] = Tz, + Hour = list_to_integer([H1, H2]), + Min = list_to_integer([M1, M2]), + Adjustment = 3600 * Hour + 60 * Min, + case Sign of + $- -> -Adjustment; + $+ -> Adjustment + end. + +local_offset(SystemTime, Unit) -> + %% Not optimized for special cases. + UniversalTime = system_time_to_universal_time(SystemTime, Unit), + LocalTime = erlang:universaltime_to_localtime(UniversalTime), + LocalSecs = datetime_to_gregorian_seconds(LocalTime), + UniversalSecs = datetime_to_gregorian_seconds(UniversalTime), + LocalSecs - UniversalSecs. + +fraction_str(1, _Time) -> + ""; +fraction_str(Factor, Time) -> + Fraction = Time rem Factor, + S = integer_to_list(abs(Fraction)), + [$. | pad(log10(Factor) - length(S), S)]. + +fraction(second, _) -> + 0; +fraction(_, "") -> + 0; +fraction(Unit, FractionStr) -> + round(factor(Unit) * list_to_float([$0|FractionStr])). + +copy_sign(N1, N2) when N2 < 0 -> -N1; +copy_sign(N1, _N2) -> N1. + +factor(second) -> 1; +factor(millisecond) -> 1000; +factor(microsecond) -> 1000000; +factor(nanosecond) -> 1000000000. + +log10(1000) -> 3; +log10(1000000) -> 6; +log10(1000000000) -> 9. + +pad(0, S) -> + S; +pad(I, S) -> + [$0 | pad(I - 1, S)]. + +pad2(N) when N < 10 -> + [$0 | integer_to_list(N)]; +pad2(N) -> + integer_to_list(N). + +pad4(N) when N < 10 -> + [$0, $0, $0 | integer_to_list(N)]; +pad4(N) when N < 100 -> + [$0, $0 | integer_to_list(N)]; +pad4(N) when N < 1000 -> + [$0 | integer_to_list(N)]; +pad4(N) -> + integer_to_list(N). |