@@ -30,7 +30,7 @@ module Data.Time.LocalTime.TimeZone.Olson.Render
3030 renderOlsonToFile,
3131 verifyOlsonLimits,
3232 putOlson,
33− splitOlson
33+ extractOlsonV1
3434)
3535where
3636
@@ -110,49 +110,35 @@ renderOlsonToFile fp olson = do
110110
111111-- | Render Olson timezone data in binary Olson timezone file format
112112-- as a lazy @ByteString@
113−putOlson :: OlsonData -> Put
114−putOlson olson = putOlsonParts version olson1 olson2 posix >> flush
113+putOlson olson@(OlsonData _ _ _ posix)
114+ | fitsInVersion1 = putOlsonPart 0 put32bitIntegral olson
115+ | otherwise = do putOlsonPart 50 put32bitIntegral olson1
116+ putOlsonPart 50 put64bitIntegral olson
117+ putPosixTZ posix
115118 where
116− (olson1, olson2, posix) = splitOlson olson
117− version
118− | olson2 /= mempty = 50
119− | otherwise = maybe 0 (const 50) $ posix >>= guard . not . null
120−
121−-- | Split Olson timezone data into three parts: timezone data that can
122−-- be rendered using Version 1 format, timezone data that can only be
123−-- rendered using Version 2 format, and the POSIX-style TZ string
124−-- if specified
125−splitOlson :: OlsonData -> (OlsonData, OlsonData, Maybe String)
126−splitOlson (OlsonData transs ttinfos leaps posix) =
127− (OlsonData transs1 ttinfos1 leaps1 Nothing,
128− OlsonData transs2 ttinfos2 leaps2 Nothing,
129− posix)
119+ olson1 = extractOlsonV1 olson
120+ fitsInVersion1 = fmap null posix /= Just False &&
121+ olson1 == olson {olsonPosixTZ = Nothing}
122+
123+-- | Extract Olson timezone data that can be rendered using Version 1 format
124+extractOlsonV1 :: OlsonData -> OlsonData
125+extractOlsonV1 (OlsonData transs ttinfos leaps _)
126+ | allV1 = OlsonData transs ttinfos leaps Nothing
127+ | otherwise = OlsonData transs1 ttinfos1 leaps1 Nothing
130128 where
131129 cutoff = 0x80000000 -- 2^31
132130 fitsIn32bits x = x < cutoff && x >= negate cutoff
133− ( leaps1 , leaps2 ) = partition (fitsIn32bits . leapTime) leaps
134− (transs1', transs2') = partition (fitsIn32bits . transTime) transs
135− assoc1 = mkAssoc [0] transs1'
136− assoc2 = mkAssoc [] transs2'
137− transs1 = mkTranss transs1' assoc1
138− transs2 = mkTranss transs2' assoc2
139− ttinfos1 = mkTtinfos assoc1
140− ttinfos2 = mkTtinfos assoc2
141− mkAssoc prepend transs' = zip
131+ leaps1 = filter (fitsIn32bits . leapTime) leaps
132+ transs1' = filter (fitsIn32bits . transTime) transs
133+ allV1 = length leaps1 == length leaps && length transs1' == length transs
134+ assoc1 = zip
142135 (sortBy (comparing $ fmap tt_ttype . listToMaybe . flip drop ttinfos) .
143− uniq . sort . (prepend ++) $ map transIndex transs')
136+ uniq . sort . (0 :) $ map transIndex transs1')
144137 [0..]
145− mkTranss transs' assoc = [t {transIndex = i} |
146− t <- transs', i <- maybeToList $ lookup (transIndex t) assoc]
147− mkTtinfos assoc = map snd . dropWhile (isNothing . fst) .
148− sortBy (comparing fst) $ zip (map (flip lookup assoc) [0..]) ttinfos
149−
150−putOlsonParts :: Word8 -> OlsonData -> OlsonData -> Maybe String -> Put
151−putOlsonParts 0 olson1 _ _ = putOlsonPart 0 put32bitIntegral olson1
152−putOlsonParts v2 olson1 olson2 posix = do
153− putOlsonPart v2 put32bitIntegral olson1
154− putOlsonPart v2 put64bitIntegral olson2
155− putPosixTZ posix
138+ transs1 = [t {transIndex = i} |
139+ t <- transs1', i <- maybeToList $ lookup (transIndex t) assoc1]
140+ ttinfos1 = map snd . dropWhile (isNothing . fst) .
141+ sortBy (comparing fst) $ zip (map (flip lookup assoc1) [0..]) ttinfos
156142
157143putOlsonPart :: Word8 -> (Integer -> Put) -> OlsonData -> Put
158144putOlsonPart version putTime (OlsonData transs ttinfos leaps _) = do