1 {-# OPTIONS -optc-DNON_POSIX_SOURCE #-}
2 -- JRS 010117: we had to say NON_POSIX_SOURCE to get the resulting .hc
3 -- to compile on sparc-solaris. Blargh.
5 -- -----------------------------------------------------------------------------
6 -- $Id: Time.hsc,v 1.11 2001/04/07 14:58:44 lewie Exp $
8 -- (c) The University of Glasgow, 1995-2001
12 Haskell 98 Time of Day Library
13 ------------------------------
15 The Time library provides standard functionality for clock times,
16 including timezone information (i.e, the functionality of "time.h",
17 adapted to the Haskell environment), It follows RFC 1129 in its use of
18 Coordinated Universal Time (UTC).
20 2000/06/17 <michael.weber@post.rwth-aachen.de>:
22 * min./max. time diff currently is restricted to
23 [minBound::Int, maxBound::Int]
25 * surely other restrictions wrt. min/max bounds
31 `showTime' (used in `instance Show ClockTime') always prints time
32 converted to the local timezone (even if it is taken from
33 `(toClockTime . toUTCTime)'), whereas `calendarTimeToString'
34 honors the tzone & tz fields and prints UTC or whatever timezone
35 is stored inside CalendarTime.
37 Maybe `showTime' should be changed to use UTC, since it would
38 better correspond to the actual representation of `ClockTime'
39 (can be done by replacing localtime(3) by gmtime(3)).
43 * add proper handling of microsecs, currently, they're mostly
46 * `formatFOO' case of `%s' is currently broken...
50 * check for unusual date cases, like 1970/1/1 00:00h, and conversions
51 between different timezone's etc.
53 * check, what needs to be in the IO monad, the current situation
54 seems to be a bit inconsistent to me
56 * check whether `isDst = -1' works as expected on other arch's
59 * add functions to parse strings to `CalendarTime' (some day...)
61 * implement padding capabilities ("%_", "%-") in `formatFOO'
63 * add rfc822 timezone (+0200 is CEST) representation ("%z") in `formatFOO'
71 , ClockTime(..) -- non-standard, lib. report gives this as abstract
75 , noTimeDiff -- non-standard (but useful when constructing TimeDiff vals.)
79 , normalizeTimeDiff -- non-standard
80 , timeDiffToString -- non-standard
81 , formatTimeDiff -- non-standard
87 , calendarTimeToString
94 #if defined(HAVE_GETTIMEOFDAY)
95 # ifdef HAVE_SYS_TIME_H
96 # include <sys/time.h>
98 #elif defined(HAVE_GETCLOCK)
99 # ifdef HAVE_SYS_TIMERS_H
101 # include <sys/timers.h>
105 #if defined(HAVE_TIME_H)
109 #ifdef HAVE_SYS_TYPES_H
110 #include <sys/types.h>
113 #ifdef HAVE_SYS_TIMEB_H
114 #include <sys/timeb.h>
117 #ifdef HAVE_WINDOWS_H
124 import PrelMarshalAlloc
125 import PrelMarshalUtils
126 import PrelMarshalError
139 -- One way to partition and give name to chunks of a year and a week:
142 = January | February | March | April
143 | May | June | July | August
144 | September | October | November | December
145 deriving (Eq, Ord, Enum, Bounded, Ix, Read, Show)
148 = Sunday | Monday | Tuesday | Wednesday
149 | Thursday | Friday | Saturday
150 deriving (Eq, Ord, Enum, Bounded, Ix, Read, Show)
152 -- @ClockTime@ is an abstract type, used for the internal clock time.
153 -- Clock times may be compared, converted to strings, or converted to an
154 -- external calendar time @CalendarTime@.
156 data ClockTime = TOD Integer -- Seconds since 00:00:00 on 1 Jan 1970
157 Integer -- Picoseconds with the specified second
160 -- When a @ClockTime@ is shown, it is converted to a string of the form
161 -- @"Mon Nov 28 21:45:41 GMT 1994"@.
163 -- For now, we are restricted to roughly:
164 -- Fri Dec 13 20:45:52 1901 through Tue Jan 19 03:14:07 2038, because
165 -- we use the C library routines based on 32 bit integers.
167 instance Show ClockTime where
168 showsPrec _ (TOD secs _nsec) =
169 showString $ unsafePerformIO $ do
170 withObject (fromIntegral secs :: CTime) $ \ p_timer -> do
171 p_tm <- localtime p_timer -- can't fail, according to POSIX
172 allocaBytes 64 $ \ p_buf -> do -- big enough for error message
173 r <- strftime p_buf 50 "%a %b %d %H:%M:%S %Z %Y"## p_tm
175 then return "ClockTime.show{Time}: internal error"
176 else peekCString p_buf
178 showList = showList__ (showsPrec 0)
181 @CalendarTime@ is a user-readable and manipulable
182 representation of the internal $ClockTime$ type. The
183 numeric fields have the following ranges.
189 year -maxInt .. maxInt [Pre-Gregorian dates are inaccurate]
190 mon 0 .. 11 [Jan = 0, Dec = 11]
194 sec 0 .. 61 [Allows for two leap seconds]
195 picosec 0 .. (10^12)-1 [This could be over-precise?]
196 wday 0 .. 6 [Sunday = 0, Saturday = 6]
197 yday 0 .. 365 [364 in non-Leap years]
198 tz -43200 .. 43200 [Variation from UTC in seconds]
201 The {\em tzname} field is the name of the time zone. The {\em isdst}
202 field indicates whether Daylight Savings Time would be in effect.
213 ctPicosec :: Integer,
220 deriving (Eq,Ord,Read,Show)
222 -- The @TimeDiff@ type records the difference between two clock times in
223 -- a user-readable way.
233 tdPicosec :: Integer -- not standard
235 deriving (Eq,Ord,Read,Show)
237 noTimeDiff :: TimeDiff
238 noTimeDiff = TimeDiff 0 0 0 0 0 0 0
240 -- -----------------------------------------------------------------------------
241 -- getClockTime returns the current time in its internal representation.
243 #if HAVE_GETTIMEOFDAY
245 allocaBytes (#const sizeof(struct timeval)) $ \ p_timeval -> do
246 throwErrnoIfMinus1_ "getClockTime" $ gettimeofday p_timeval nullPtr
247 sec <- (#peek struct timeval,tv_sec) p_timeval :: IO CLong
248 usec <- (#peek struct timeval,tv_usec) p_timeval :: IO CLong
249 return (TOD (fromIntegral sec) ((fromIntegral usec) * 1000))
253 allocaBytes (#const sizeof(struct timeb)) $ \ p_timeb -> do
255 sec <- (#peek struct timeb,time) p_timeb :: IO CTime
256 msec <- (#peek struct timeb,millitm) p_timeb :: IO CUShort
257 return (TOD (fromIntegral sec) (fromIntegral msec * 1000{-ToDo: correct???-}))
259 #else /* use POSIX time() */
261 secs <- time nullPtr -- can't fail, according to POSIX
262 return (TOD (fromIntegral secs) 0)
266 -- -----------------------------------------------------------------------------
267 -- addToClockTime d t adds a time difference d and a
268 -- clock time t to yield a new clock time. The difference d
269 -- may be either positive or negative. diffClockTimes t1 t2 returns
270 -- the difference between two clock times t1 and t2 as a TimeDiff.
272 addToClockTime :: TimeDiff -> ClockTime -> ClockTime
273 addToClockTime (TimeDiff year mon day hour min sec psec)
276 sec_diff = toInteger sec +
278 3600 * toInteger hour +
279 24 * 3600 * toInteger day
280 cal = toUTCTime (TOD (c_sec + sec_diff) (c_psec + psec))
282 new_mon = fromEnum (ctMonth cal) + r_mon
284 | new_mon < 0 = (toEnum (12 + new_mon), (-1))
285 | new_mon > 11 = (toEnum (new_mon `mod` 12), 1)
286 | otherwise = (toEnum new_mon, 0)
288 (r_yr, r_mon) = mon `quotRem` 12
290 year' = ctYear cal + year + r_yr + yr_diff
292 toClockTime cal{ctMonth=month', ctYear=year'}
294 diffClockTimes :: ClockTime -> ClockTime -> TimeDiff
295 -- diffClockTimes is meant to be the dual to `addToClockTime'.
296 -- If you want to have the TimeDiff properly splitted, use
297 -- `normalizeTimeDiff' on this function's result
299 -- CAVEAT: see comment of normalizeTimeDiff
300 diffClockTimes (TOD sa pa) (TOD sb pb) =
301 noTimeDiff{ tdSec = fromIntegral (sa - sb)
302 -- FIXME: can handle just 68 years...
303 , tdPicosec = pa - pb
307 normalizeTimeDiff :: TimeDiff -> TimeDiff
308 -- FIXME: handle psecs properly
309 -- FIXME: ?should be called by formatTimeDiff automagically?
311 -- when applied to something coming out of `diffClockTimes', you loose
312 -- the duality to `addToClockTime', since a year does not always have
315 -- apply this function as late as possible to prevent those "rounding"
317 normalizeTimeDiff td =
324 + 365 * tdYear td))))
326 (diffYears, rest1) = rest0 `quotRem` (365 * 24 * 3600)
327 (diffMonths, rest2) = rest1 `quotRem` (30 * 24 * 3600)
328 (diffDays, rest3) = rest2 `quotRem` (24 * 3600)
329 (diffHours, rest4) = rest3 `quotRem` 3600
330 (diffMins, diffSecs) = rest4 `quotRem` 60
332 td{ tdYear = diffYears
333 , tdMonth = diffMonths
340 -- -----------------------------------------------------------------------------
341 -- How do we deal with timezones on this architecture?
343 -- The POSIX way to do it is through the global variable tzname[].
344 -- But that's crap, so we do it The BSD Way if we can: namely use the
345 -- tm_zone and tm_gmtoff fields of struct tm, if they're available.
347 zone :: Ptr CTm -> IO (Ptr CChar)
348 gmtoff :: Ptr CTm -> IO CLong
350 zone x = (#peek struct tm,tm_zone) x
351 gmtoff x = (#peek struct tm,tm_gmtoff) x
353 #else /* ! HAVE_TM_ZONE */
354 # if HAVE_TZNAME || _WIN32
355 # if cygwin32_TARGET_OS
356 # define tzname _tzname
358 # ifndef mingw32_TARGET_OS
359 foreign label tzname :: Ptr (Ptr CChar)
361 foreign import "ghcTimezone" unsafe timezone :: Ptr CLong
362 foreign import "ghcTzname" unsafe tzname :: Ptr (Ptr CChar)
363 # def inline long *ghcTimezone(void) { return &_timezone; }
364 # def inline char **ghcTzname(void) { return _tzname; }
367 dst <- (#peek struct tm,tm_isdst) x
368 if dst then peekElemOff tzname 1 else peekElemOff tzname 0
369 # else /* ! HAVE_TZNAME */
370 -- We're in trouble. If you should end up here, please report this as a bug.
371 # error "Don't know how to get at timezone name on your OS."
372 # endif /* ! HAVE_TZNAME */
374 -- Get the offset in secs from UTC, if (struct tm) doesn't supply it. */
375 #if defined(mingw32_TARGET_OS) || defined(cygwin32_TARGET_OS)
376 #define timezone _timezone
380 foreign label altzone :: Ptr CTime
381 foreign label timezone :: Ptr CTime
383 dst <- (#peek struct tm,tm_isdst) x
384 tz <- if dst then peek altzone else peek timezone
385 return (fromIntegral tz)
386 # define GMTOFF(x) (((struct tm *)x)->tm_isdst ? altzone : timezone )
387 # else /* ! HAVE_ALTZONE */
388 -- Assume that DST offset is 1 hour ...
390 dst <- (#peek struct tm,tm_isdst) x
392 if dst then return (fromIntegral tz - 3600) else return tz
393 # endif /* ! HAVE_ALTZONE */
394 #endif /* ! HAVE_TM_ZONE */
396 -- -----------------------------------------------------------------------------
397 -- toCalendarTime t converts t to a local time, modified by
398 -- the current timezone and daylight savings time settings. toUTCTime
399 -- t converts t into UTC time. toClockTime l converts l into the
400 -- corresponding internal ClockTime. The wday, yday, tzname, and isdst fields
404 toCalendarTime :: ClockTime -> IO CalendarTime
405 toCalendarTime = clockToCalendarTime localtime False
407 toUTCTime :: ClockTime -> CalendarTime
408 toUTCTime = unsafePerformIO . clockToCalendarTime gmtime True
410 -- ToDo: should be made thread safe, because localtime uses static storage,
411 -- or use the localtime_r version.
412 clockToCalendarTime :: (Ptr CTime -> IO (Ptr CTm)) -> Bool -> ClockTime
414 clockToCalendarTime fun is_utc (TOD secs psec) = do
415 withObject (fromIntegral secs :: CTime) $ \ p_timer -> do
416 p_tm <- fun p_timer -- can't fail, according to POSIX
417 sec <- (#peek struct tm,tm_sec ) p_tm :: IO CInt
418 min <- (#peek struct tm,tm_min ) p_tm :: IO CInt
419 hour <- (#peek struct tm,tm_hour ) p_tm :: IO CInt
420 mday <- (#peek struct tm,tm_mday ) p_tm :: IO CInt
421 mon <- (#peek struct tm,tm_mon ) p_tm :: IO CInt
422 year <- (#peek struct tm,tm_year ) p_tm :: IO CInt
423 wday <- (#peek struct tm,tm_wday ) p_tm :: IO CInt
424 yday <- (#peek struct tm,tm_yday ) p_tm :: IO CInt
425 isdst <- (#peek struct tm,tm_isdst) p_tm :: IO CInt
429 tzname <- peekCString zone
431 let month | mon >= 0 && mon <= 11 = toEnum (fromIntegral mon)
432 | otherwise = error ("toCalendarTime: illegal month value: " ++ show mon)
435 (1900 + fromIntegral year)
442 (toEnum (fromIntegral wday))
444 (if is_utc then "UTC" else tzname)
445 (if is_utc then 0 else fromIntegral tz)
446 (if is_utc then False else isdst /= 0))
449 toClockTime :: CalendarTime -> ClockTime
450 toClockTime (CalendarTime year mon mday hour min sec psec
451 _wday _yday _tzname tz isdst) =
453 -- `isDst' causes the date to be wrong by one hour...
454 -- FIXME: check, whether this works on other arch's than Linux, too...
456 -- so we set it to (-1) (means `unknown') and let `mktime' determine
458 let isDst = -1 :: CInt in -- if isdst then (1::Int) else 0
460 if psec < 0 || psec > 999999999999 then
461 error "Time.toClockTime: picoseconds out of range"
462 else if tz < -43200 || tz > 43200 then
463 error "Time.toClockTime: timezone offset out of range"
466 allocaBytes (#const sizeof(struct tm)) $ \ p_tm -> do
467 (#poke struct tm,tm_sec ) p_tm (fromIntegral sec :: CInt)
468 (#poke struct tm,tm_min ) p_tm (fromIntegral min :: CInt)
469 (#poke struct tm,tm_hour ) p_tm (fromIntegral hour :: CInt)
470 (#poke struct tm,tm_mday ) p_tm (fromIntegral mday :: CInt)
471 (#poke struct tm,tm_mon ) p_tm (fromIntegral (fromEnum mon) :: CInt)
472 (#poke struct tm,tm_year ) p_tm (fromIntegral year - 1900 :: CInt)
473 (#poke struct tm,tm_isdst) p_tm isDst
474 t <- throwIf (== -1) (\_ -> "Time.toClockTime: invalid input")
477 -- mktime expects its argument to be in the local timezone, but
478 -- toUTCTime makes UTC-encoded CalendarTime's ...
480 -- Since there is no any_tz_struct_tm-to-time_t conversion
481 -- function, we have to fake one... :-) If not in all, it works in
482 -- most cases (before, it was the other way round...)
484 -- Luckily, mktime tells us, what it *thinks* the timezone is, so,
485 -- to compensate, we add the timezone difference to mktime's
488 gmtoff <- gmtoff p_tm
489 let res = fromIntegral t + tz - fromIntegral gmtoff
490 return (TOD (fromIntegral res) 0)
492 -- -----------------------------------------------------------------------------
493 -- Converting time values to strings.
495 calendarTimeToString :: CalendarTime -> String
496 calendarTimeToString = formatCalendarTime defaultTimeLocale "%c"
498 formatCalendarTime :: TimeLocale -> String -> CalendarTime -> String
499 formatCalendarTime l fmt (CalendarTime year mon day hour min sec _
500 wday yday tzname _ _) =
502 where doFmt ('%':'-':cs) = doFmt ('%':cs) -- padding not implemented
503 doFmt ('%':'_':cs) = doFmt ('%':cs) -- padding not implemented
504 doFmt ('%':c:cs) = decode c ++ doFmt cs
505 doFmt (c:cs) = c : doFmt cs
508 decode 'A' = fst (wDays l !! fromEnum wday) -- day of the week, full name
509 decode 'a' = snd (wDays l !! fromEnum wday) -- day of the week, abbrev.
510 decode 'B' = fst (months l !! fromEnum mon) -- month, full name
511 decode 'b' = snd (months l !! fromEnum mon) -- month, abbrev
512 decode 'h' = snd (months l !! fromEnum mon) -- ditto
513 decode 'C' = show2 (year `quot` 100) -- century
514 decode 'c' = doFmt (dateTimeFmt l) -- locale's data and time format.
515 decode 'D' = doFmt "%m/%d/%y"
516 decode 'd' = show2 day -- day of the month
517 decode 'e' = show2' day -- ditto, padded
518 decode 'H' = show2 hour -- hours, 24-hour clock, padded
519 decode 'I' = show2 (to12 hour) -- hours, 12-hour clock
520 decode 'j' = show3 yday -- day of the year
521 decode 'k' = show2' hour -- hours, 24-hour clock, no padding
522 decode 'l' = show2' (to12 hour) -- hours, 12-hour clock, no padding
523 decode 'M' = show2 min -- minutes
524 decode 'm' = show2 (fromEnum mon+1) -- numeric month
526 decode 'p' = (if hour < 12 then fst else snd) (amPm l) -- am or pm
527 decode 'R' = doFmt "%H:%M"
528 decode 'r' = doFmt (time12Fmt l)
529 decode 'T' = doFmt "%H:%M:%S"
531 decode 'S' = show2 sec -- seconds
532 decode 's' = show2 sec -- number of secs since Epoch. (ToDo.)
533 decode 'U' = show2 ((yday + 7 - fromEnum wday) `div` 7) -- week number, starting on Sunday.
534 decode 'u' = show (let n = fromEnum wday in -- numeric day of the week (1=Monday, 7=Sunday)
535 if n == 0 then 7 else n)
536 decode 'V' = -- week number (as per ISO-8601.)
537 let (week, days) = -- [yep, I've always wanted to be able to display that too.]
538 (yday + 7 - if fromEnum wday > 0 then
539 fromEnum wday - 1 else 6) `divMod` 7
540 in show2 (if days >= 4 then
542 else if week == 0 then 53 else week)
544 decode 'W' = -- week number, weeks starting on monday
545 show2 ((yday + 7 - if fromEnum wday > 0 then
546 fromEnum wday - 1 else 6) `div` 7)
547 decode 'w' = show (fromEnum wday) -- numeric day of the week, weeks starting on Sunday.
548 decode 'X' = doFmt (timeFmt l) -- locale's preferred way of printing time.
549 decode 'x' = doFmt (dateFmt l) -- locale's preferred way of printing dates.
550 decode 'Y' = show year -- year, including century.
551 decode 'y' = show2 (year `rem` 100) -- year, within century.
552 decode 'Z' = tzname -- timezone name
557 show2, show2', show3 :: Int -> String
558 show2 x = [intToDigit (x `quot` 10), intToDigit (x `rem` 10)]
560 show2' x = if x < 10 then [ ' ', intToDigit x] else show2 x
562 show3 x = intToDigit (x `quot` 100) : show2 (x `rem` 100)
565 to12 h = let h' = h `mod` 12 in if h' == 0 then 12 else h'
567 -- Useful extensions for formatting TimeDiffs.
569 timeDiffToString :: TimeDiff -> String
570 timeDiffToString = formatTimeDiff defaultTimeLocale "%c"
572 formatTimeDiff :: TimeLocale -> String -> TimeDiff -> String
573 formatTimeDiff l fmt td@(TimeDiff year month day hour min sec _)
577 doFmt ('%':'-':cs) = doFmt ('%':cs) -- padding not implemented
578 doFmt ('%':'_':cs) = doFmt ('%':cs) -- padding not implemented
579 doFmt ('%':c:cs) = decode c ++ doFmt cs
580 doFmt (c:cs) = c : doFmt cs
584 'B' -> fst (months l !! fromEnum month)
585 'b' -> snd (months l !! fromEnum month)
586 'h' -> snd (months l !! fromEnum month)
587 'c' -> defaultTimeDiffFmt td
588 'C' -> show2 (year `quot` 100)
589 'D' -> doFmt "%m/%d/%y"
593 'I' -> show2 (to12 hour)
595 'l' -> show2' (to12 hour)
597 'm' -> show2 (fromEnum month + 1)
599 'p' -> (if hour < 12 then fst else snd) (amPm l)
601 'r' -> doFmt (time12Fmt l)
602 'T' -> doFmt "%H:%M:%S"
605 's' -> show2 sec -- Implementation-dependent, sez the lib doc..
606 'X' -> doFmt (timeFmt l)
607 'x' -> doFmt (dateFmt l)
609 'y' -> show2 (year `rem` 100)
613 defaultTimeDiffFmt (TimeDiff year month day hour min sec _) =
614 foldr (\ (v,s) rest ->
616 then show v ++ ' ':(addS v s)
617 ++ if null rest then "" else ", "
621 (zip [year, month, day, hour, min, sec] (intervals l))
623 addS v s = if abs v == 1 then fst s else snd s
626 -- -----------------------------------------------------------------------------
627 -- Foreign time interface (POSIX)
629 type CTm = () -- struct tm
631 foreign import unsafe localtime :: Ptr CTime -> IO (Ptr CTm)
632 foreign import unsafe gmtime :: Ptr CTime -> IO (Ptr CTm)
633 foreign import unsafe strftime :: Ptr CChar -> CSize -> Addr## -> Ptr CTm -> IO CSize
634 foreign import unsafe mktime :: Ptr CTm -> IO CTime
635 foreign import unsafe time :: Ptr CTime -> IO CTime
637 #if HAVE_GETTIMEOFDAY
639 foreign import unsafe gettimeofday :: Ptr CTimeVal -> Ptr () -> IO CInt
644 #ifndef mingw32_TARGET_OS
645 foreign import unsafe ftime :: Ptr CTimeB -> IO CInt
647 foreign import unsafe ftime :: Ptr CTimeB -> IO ()