pure lua version of os.date("!*t", time)

time.lua

-- port from golang: https://golang.org/src/time/time.go
--

local secondsPerMinute = 60
local secondsPerHour   = 60 * 60
local secondsPerDay    = 24 * secondsPerHour
local secondsPerWeek   = 7 * secondsPerDay
local daysPer400Years  = 365*400 + 97
local daysPer100Years  = 365*100 + 24
local daysPer4Years    = 365*4 + 1

local unixBase = (1969*365 + 1969//4 - 1969//100 + 1969//400) * secondsPerDay

-- daysBefore[m] counts the number of days in a non-leap year
-- before month m begins. There is an entry for m=12, counting
-- the number of days before January of next year (365).
local daysBefore = {
                0,
                31,
                31 + 28,
                31 + 28 + 31,
                31 + 28 + 31 + 30,
                31 + 28 + 31 + 30 + 31,
                31 + 28 + 31 + 30 + 31 + 30,
                31 + 28 + 31 + 30 + 31 + 30 + 31,
                31 + 28 + 31 + 30 + 31 + 30 + 31 + 31,
                31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30,
                31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31,
                31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31 + 30,
                31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31 + 30 + 31,
}

local January   = 1
local February  = 2
local March     = 3
local April     = 4
local May       = 5
local June      = 6
local July      = 7
local August    = 8
local September = 9
local October   = 10
local November  = 11
local December  = 12

local Sunday    = 1
local Monday    = 2
local Tuesday   = 3
local Wednesday = 4
local Thursday  = 5
local Friday    = 6
local Saturday  = 7

-- absTimestamp returns the absolute second from {year=1, month=1, day=1, hour=0, mintue=0, second=0}
local function absTimestamp(ts)
    return ts + unixBase
end

local function isLeap(year)
    return year%4 == 0 and (year%100 ~= 0 or year%400 == 0)
end

local function absWeekday(abs)
    -- January 1 of the absolute year, like January 1 of 2001, was a Monday.
    local sec = (abs+1*secondsPerDay) % secondsPerWeek
    return (sec // secondsPerDay) + 1
end

-- convert timestamp to year, month, day, yday
local function absDate(abs)
    local day = abs // secondsPerDay

    local n, y
    -- Account for 400 year cycles.
    n = day // daysPer400Years
    y = 400 * n
    day = day - daysPer400Years * n

    -- Cut off 100-year cycles.
    -- The last cycle has one extra leap year, so on the last day
    -- of that year, day / daysPer100Years will be 4 instead of 3.
    -- Cut it back down to 3 by subtracting n>>2.
    n = day // daysPer100Years
    n = n - (n >> 2)
    y = y + 100 *n
    day = day - daysPer100Years * n

    -- Cut off 4-year cycles.
    -- The last cycle has a missing leap year, which does not
    -- affect the computation.
    n = day // daysPer4Years
    y = y + 4 * n
    day = day - daysPer4Years * n

    -- Cut off years within a 4-year cycle.
    -- The last year is a leap year, so on the last day of that year,
    -- day / 365 will be 4 instead of 3. Cut it back down to 3
    -- by subtracting n>>2.
    n = day // 365
    n = n - (n >> 2)
    y = y + n
    day = day - 365 * n

    local year = y + 1
    local yday = day + 1

    if isLeap(year) then
        -- Leap year
        if day > 31+29-1 then
            -- After leap day; pretend it wasn't there.
            day = day - 1
        elseif day == 31+29-1 then
            return year, February, 29, yday
        end
    end

    -- Estimate month on assumption that every month has 31 days.
    -- The estimate may be too low by at most one month, so adjust.
    local month = (day // 31) + 1
    local monthDayEnd = daysBefore[month + 1]
    local monthDayBegin

    if day >= monthDayEnd then
        month = month + 1
        monthDayBegin = monthDayEnd
    else
        monthDayBegin = daysBefore[month]
    end

    day = day - monthDayBegin + 1
    return year, month, day, yday
end

local M = {}

M.TZ = 8
function M.localdate(sec, tz, t)
    local tz = tz or M.TZ
    return M.date(sec + tz*secondsPerHour, t)
end

function M.date(sec, t)
    local abs = absTimestamp(sec)
    local t = t or {}
    t.year, t.month, t.day, t.yday = absDate(abs)
    t.wday = absWeekday(abs)

    local seconds = abs % secondsPerDay
    t.hour = seconds // secondsPerHour
    seconds = seconds - (t.hour * secondsPerHour)
    t.min = seconds // secondsPerMinute
    t.sec = seconds - (t.min * secondsPerMinute)
    return t
end

local tmp = {}

function M.format(sec, utc)
    if utc then
        M.date(sec, tmp)
    else
        M.localdate(sec, nil, tmp)
    end

    return string.format("%4d-%02d-%02d %02d:%02d:%02d",
        tmp.year, tmp.month, tmp.day, tmp.hour, tmp.min, tmp.sec)
end

-- test functions
--
function M.run_random_test()
    for i=1, 100 do
        local ts = math.random(0, 2^31)
        local t1 = os.date("!*t", ts)
        local t2 = M.date(ts)

        for k,v in pairs(t1) do
            if k ~= "isdst" then
                assert(v == t2[k], k)
            end
        end
    end
end

function M.run_full_test()
    local total = 2^31
    for i=1, total do
        local t1 = os.date("!*t", i)
        local t2 = M.date(i, tmp)

        for k,v in pairs(t1) do
            if k ~= "isdst" then
                assert(v == t2[k], k)
            end
        end

        if i % 100000 == 0 then
            print("------------------------:", total, i)
        end
    end
end

function M.run_profile_test(times)
    local times = times and times > 0 or 1000000

    local from = math.random(2^31 - times)
    local to = from + times

    local t1 = os.clock()
    for ts = from, to do
        os.date("!*t", ts)
    end

    local t = {}
    local t2 = os.clock()
    for ts = from, to do
        M.date(ts, t)
    end
    local t3 = os.clock()

    print(string.format("%d times call %s cost %s seconds", times, "os.date", t2-t1))
    print(string.format("%d times call %s cost %s seconds", times, "M.date", t3-t2))
end
return M

我是@xjdrew的脑残粉