[commit: packages/time] format-widths, ghc, improve-leapseconds, master, posix-perf, tasty, wip/travis: getCurrentTimezone, with test (cb6d14e)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/time

On branches: format-widths,ghc,improve-leapseconds,master,posix-perf,tasty,wip/travis
Link       : http://git.haskell.org/packages/time.git/commitdiff/cb6d14eea0baae5259775481c8b7cc0b584b1219

>---------------------------------------------------------------

commit cb6d14eea0baae5259775481c8b7cc0b584b1219
Author: Ashley Yakeley <ashley at semantic.org>
Date:   Sun Mar 20 22:37:22 2005 -0800

    getCurrentTimezone, with test
    
    darcs-hash:20050321063722-ac6dd-9792ff0e686b52fa1c9770058f77e6614445f6fb


>---------------------------------------------------------------

cb6d14eea0baae5259775481c8b7cc0b584b1219
 CurrentTime.hs          |  6 +++---
 Makefile                |  5 ++++-
 System/Time/Calendar.hs | 16 +++++++++++++++-
 timestuff.c             | 11 +++++++++++
 timestuff.h             |  1 +
 5 files changed, 34 insertions(+), 5 deletions(-)

diff --git a/CurrentTime.hs b/CurrentTime.hs
index 19e46c1..770699d 100644
--- a/CurrentTime.hs
+++ b/CurrentTime.hs
@@ -4,11 +4,11 @@ import System.Time.Clock
 import System.Time.TAI
 import System.Time.Calendar
 
-myzone :: TimeZone
-myzone = hoursToTimezone (- 8)
-
 main :: IO ()
 main = do
 	now <- getCurrentTime
 	putStrLn (show (utctDay now) ++ "," ++ show (utctDayTime now))
+	putStrLn (show (utcToCalendar utc now))
+	myzone <- getCurrentTimezone
+	putStrLn ("timezone minutes: " ++ show (timezoneToMinutes myzone))
 	putStrLn (show (utcToCalendar myzone now))
diff --git a/Makefile b/Makefile
index 82f4d8a..e29aaa5 100644
--- a/Makefile
+++ b/Makefile
@@ -11,7 +11,10 @@ TestTime: TestTime.o libTimeLib.a
 CurrentTime: CurrentTime.o libTimeLib.a
 	ghc $^ -o $@
 
-libTimeLib.a: $(patsubst %.hs,%.o,$(SRCS))
+timestuff.o: timestuff.c timestuff.h
+	gcc -o $@ -c $<
+
+libTimeLib.a: $(patsubst %.hs,%.o,$(SRCS)) timestuff.o
 	rm -f $@
 	ar cru $@ $^
 	ranlib $@
diff --git a/System/Time/Calendar.hs b/System/Time/Calendar.hs
index 5cc646a..683e017 100644
--- a/System/Time/Calendar.hs
+++ b/System/Time/Calendar.hs
@@ -1,4 +1,4 @@
-{-# OPTIONS -Wall -Werror #-}
+{-# OPTIONS -ffi -Wall -Werror #-}
 
 module System.Time.Calendar
 (
@@ -6,6 +6,7 @@ module System.Time.Calendar
 	TimeZone,timezoneToMinutes,minutesToTimezone,hoursToTimezone,utc,
 
 	-- getting the locale time zone
+	getCurrentTimezone,
 
 	-- Gregorian "calendrical" format
 	TimeOfDay(..),CalendarDay(..),CalendarTime(..),
@@ -29,6 +30,9 @@ import System.Time.Clock
 import Data.Fixed
 import Data.Char
 
+import Foreign
+import Foreign.C
+
 -- | count of minutes
 newtype TimeZone = MkTimeZone {
 	timezoneToMinutes :: Int
@@ -44,6 +48,16 @@ hoursToTimezone i = minutesToTimezone (60 * i)
 utc :: TimeZone
 utc = minutesToTimezone 0
 
+foreign import ccall unsafe "timestuff.h get_current_timezone_seconds" get_current_timezone_seconds :: IO CLong
+
+-- | Get the current time-zone
+getCurrentTimezone :: IO TimeZone
+getCurrentTimezone = do
+	secs <- get_current_timezone_seconds
+	case secs of
+		0x80000000 -> fail "localtime_r failed"
+		_ -> return (minutesToTimezone (div (fromIntegral secs) 60))
+
 -- | time of day as represented in hour, minute and second (with picoseconds), typically used to express local time of day
 data TimeOfDay = TimeOfDay {
 	todHour    :: Int,
diff --git a/timestuff.c b/timestuff.c
new file mode 100644
index 0000000..79139bd
--- /dev/null
+++ b/timestuff.c
@@ -0,0 +1,11 @@
+#include <sys/time.h>
+
+long int get_current_timezone_seconds ()
+{
+	time_t t = 0;
+	struct tm tmd;
+	struct tm* ptm = localtime_r(&t,&tmd);
+	if (ptm)
+		return ptm -> tm_gmtoff;
+	else return 0x80000000;
+}
diff --git a/timestuff.h b/timestuff.h
new file mode 100644
index 0000000..f58c0f1
--- /dev/null
+++ b/timestuff.h
@@ -0,0 +1 @@
+long int get_current_timezone_seconds ();