diff options
Diffstat (limited to 'lib/stdlib/src/calendar.erl')
| -rw-r--r-- | lib/stdlib/src/calendar.erl | 94 |
1 files changed, 68 insertions, 26 deletions
diff --git a/lib/stdlib/src/calendar.erl b/lib/stdlib/src/calendar.erl index bb5d450cd6..3a8fe2211b 100644 --- a/lib/stdlib/src/calendar.erl +++ b/lib/stdlib/src/calendar.erl @@ -1,7 +1,7 @@ %% %% %CopyrightBegin% %% -%% Copyright Ericsson AB 1996-2018. 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. @@ -357,13 +357,17 @@ rfc3339_to_system_time(DateTimeString) -> rfc3339_to_system_time(DateTimeString, Options) -> Unit = proplists:get_value(unit, Options, second), %% _T is the character separating the date and the time: - {DateStr, [_T|TimeStr]} = lists:split(10, DateTimeString), - {TimeStr2, TimeStr3} = lists:split(8, TimeStr), - {ok, [Hour, Min, Sec], []} = io_lib:fread("~d:~d:~d", TimeStr2), - {ok, [Year, Month, Day], []} = io_lib:fread("~d-~d-~d", DateStr), + [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, TimeStr3), + {FractionStr, UtcOffset} = lists:splitwith(IsFractionChar, TimeStr), Time = datetime_to_system_time(DateTime), Secs = Time - offset_adjustment(Time, second, UtcOffset), check(DateTimeString, Options, Secs), @@ -451,8 +455,9 @@ system_time_to_rfc3339(Time, Options) -> DateTime = system_time_to_datetime(Secs), {{Year, Month, Day}, {Hour, Min, Sec}} = DateTime, FractionStr = fraction_str(Factor, AdjustedTime), - flat_fwrite("~4.10.0B-~2.10.0B-~2.10.0B~c~2.10.0B:~2.10.0B:~2.10.0B~s~s", - [Year, Month, Day, T, Hour, Min, Sec, FractionStr, Offset]). + L = [pad4(Year), "-", pad2(Month), "-", pad2(Day), [T], + pad2(Hour), ":", pad2(Min), ":", pad2(Sec), FractionStr, Offset], + lists:append(L). %% time_difference(T1, T2) = Tdiff %% @@ -529,24 +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. @@ -663,7 +685,7 @@ offset(OffsetOption, Secs0) when OffsetOption =:= ""; Secs = abs(Secs0), Hour = Secs div 3600, Min = (Secs rem 3600) div 60, - io_lib:fwrite("~c~2.10.0B:~2.10.0B", [Sign, Hour, Min]); + [Sign | lists:append([pad2(Hour), ":", pad2(Min)])]; offset(OffsetOption, _Secs) -> OffsetOption. @@ -678,8 +700,10 @@ offset_string_adjustment(_Time, _Unit, "Z") -> 0; offset_string_adjustment(_Time, _Unit, "z") -> 0; -offset_string_adjustment(_Time, _Unit, [Sign|Tz]) -> - {ok, [Hour, Min], []} = io_lib:fread("~d:~d", Tz), +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 $- -> -Adjustment; @@ -687,8 +711,9 @@ offset_string_adjustment(_Time, _Unit, [Sign|Tz]) -> end. local_offset(SystemTime, Unit) -> - LocalTime = system_time_to_local_time(SystemTime, Unit), + %% Not optimized for special cases. UniversalTime = system_time_to_universal_time(SystemTime, Unit), + LocalTime = erlang:universaltime_to_localtime(UniversalTime), LocalSecs = datetime_to_gregorian_seconds(LocalTime), UniversalSecs = datetime_to_gregorian_seconds(UniversalTime), LocalSecs - UniversalSecs. @@ -697,7 +722,8 @@ fraction_str(1, _Time) -> ""; fraction_str(Factor, Time) -> Fraction = Time rem Factor, - io_lib:fwrite(".~*..0B", [log10(Factor), abs(Fraction)]). + S = integer_to_list(abs(Fraction)), + [$. | pad(log10(Factor) - length(S), S)]. fraction(second, _) -> 0; @@ -718,5 +744,21 @@ log10(1000) -> 3; log10(1000000) -> 6; log10(1000000000) -> 9. -flat_fwrite(F, S) -> - lists:flatten(io_lib:fwrite(F, S)). +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). |