/usr/lib/hugs/packages/time/Data/Time/LocalTime/TimeZone.hs is in libhugs-time-bundled 98.200609.21-5.4build1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
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-- #hide
module Data.Time.LocalTime.TimeZone
(
-- * Time zones
TimeZone(..),timeZoneOffsetString,minutesToTimeZone,hoursToTimeZone,utc,
-- getting the locale time zone
getTimeZone,getCurrentTimeZone
) where
--import System.Time.Calendar.Format
import Data.Time.Calendar.Private
import Data.Time.Clock
import Data.Time.Clock.POSIX
import Foreign
import Foreign.C
-- | A TimeZone is a whole number of minutes offset from UTC, together with a name and a \"just for summer\" flag.
data TimeZone = TimeZone {
-- | The number of minutes offset from UTC. Positive means local time will be later in the day than UTC.
timeZoneMinutes :: Int,
-- | Is this time zone just persisting for the summer?
timeZoneSummerOnly :: Bool,
-- | The name of the zone, typically a three- or four-letter acronym.
timeZoneName :: String
} deriving (Eq,Ord)
-- | Create a nameless non-summer timezone for this number of minutes
minutesToTimeZone :: Int -> TimeZone
minutesToTimeZone m = TimeZone m False ""
-- | Create a nameless non-summer timezone for this number of hours
hoursToTimeZone :: Int -> TimeZone
hoursToTimeZone i = minutesToTimeZone (60 * i)
showT :: Int -> String
showT t = (show2 (div t 60)) ++ (show2 (mod t 60))
-- | Text representing the offset of this timezone, such as \"-0800\" or \"+0400\" (like %z in formatTime)
timeZoneOffsetString :: TimeZone -> String
timeZoneOffsetString (TimeZone t _ _) | t < 0 = '-':(showT (negate t))
timeZoneOffsetString (TimeZone t _ _) = '+':(showT t)
instance Show TimeZone where
show zone@(TimeZone _ _ "") = timeZoneOffsetString zone
show (TimeZone _ _ name) = name
-- | The UTC time zone
utc :: TimeZone
utc = TimeZone 0 False "UTC"
{-# CFILES cbits/HsTime.c #-}
foreign import ccall unsafe "HsTime.h get_current_timezone_seconds" get_current_timezone_seconds :: CTime -> Ptr CInt -> Ptr CString -> IO CLong
posixToCTime :: POSIXTime -> CTime
posixToCTime = fromInteger . floor
-- | Get the local time-zone for a given time (varying as per summertime adjustments)
getTimeZone :: UTCTime -> IO TimeZone
getTimeZone time = with 0 (\pdst -> with nullPtr (\pcname -> do
secs <- get_current_timezone_seconds (posixToCTime (utcTimeToPOSIXSeconds time)) pdst pcname
case secs of
0x80000000 -> fail "localtime_r failed"
_ -> do
dst <- peek pdst
cname <- peek pcname
name <- peekCString cname
return (TimeZone (div (fromIntegral secs) 60) (dst == 1) name)
))
-- | Get the current time-zone
getCurrentTimeZone :: IO TimeZone
getCurrentTimeZone = getCurrentTime >>= getTimeZone
|