{-# LANGUAGE DeriveDataTypeable, ViewPatterns #-} {-# OPTIONS_GHC -O2 -Wall #-} import Prelude hiding (catch) import Control.Applicative import Control.Monad import Control.Monad.CatchIO import qualified Data.ByteString.Lazy as B import Data.Char import Data.Dynamic import Data.Int import qualified Data.Map as M import Data.Time.Clock.POSIX import Data.Time.Format import Network.CGI import Numeric import System.FilePath import System.IO import System.IO.Error (isDoesNotExistError, isPermissionError) import System.IO.Unsafe import System.Locale import System.Posix import System.Posix.Handle encodings :: M.Map String String encodings = M.fromList [ (".bz2", "bzip2"), (".gz", "gzip"), (".z", "compress") ] types :: M.Map String String types = M.fromList [ (".avi", "video/x-msvideo"), (".css", "text/css"), (".doc", "application/msword"), (".docm", "application/vnd.ms-word.document.macroEnabled.12"), (".docx", "application/vnd.openxmlformats-officedocument.wordprocessingml.document"), (".dot", "application/msword"), (".dotm", "application/vnd.ms-word.template.macroEnabled.12"), (".dotx", "application/vnd.openxmlformats-officedocument.wordprocessingml.template"), (".gif", "image/gif"), (".htm", "text/html"), (".html", "text/html"), (".ico", "image/vnd.microsoft.icon"), (".il", "application/octet-stream"), (".jar", "application/java-archive"), (".jpeg", "image/jpeg"), (".jpg", "image/jpeg"), (".js", "application/x-javascript"), (".mid", "audio/midi"), (".midi", "audio/midi"), (".mov", "video/quicktime"), (".mp3", "audio/mpeg"), (".mpeg", "video/mpeg"), (".mpg", "video/mpeg"), (".odb", "application/vnd.oasis.opendocument.database"), (".odc", "application/vnd.oasis.opendocument.chart"), (".odf", "application/vnd.oasis.opendocument.formula"), (".odg", "application/vnd.oasis.opendocument.graphics"), (".odi", "application/vnd.oasis.opendocument.image"), (".odm", "application/vnd.oasis.opendocument.text-master"), (".odp", "application/vnd.oasis.opendocument.presentation"), (".ods", "application/vnd.oasis.opendocument.spreadsheet"), (".odt", "application/vnd.oasis.opendocument.text"), (".otf", "application/octet-stream"), (".otg", "application/vnd.oasis.opendocument.graphics-template"), (".oth", "application/vnd.oasis.opendocument.text-web"), (".otp", "application/vnd.oasis.opendocument.presentation-template"), (".ots", "application/vnd.oasis.opendocument.spreadsheet-template"), (".ott", "application/vnd.oasis.opendocument.text-template"), (".pdf", "application/pdf"), (".png", "image/png"), (".pot", "application/vnd.ms-powerpoint"), (".potm", "application/vnd.ms-powerpoint.template.macroEnabled.12"), (".potx", "application/vnd.openxmlformats-officedocument.presentationml.template"), (".ppa", "application/vnd.ms-powerpoint"), (".ppam", "application/vnd.ms-powerpoint.addin.macroEnabled.12"), (".pps", "application/vnd.ms-powerpoint"), (".ppsm", "application/vnd.ms-powerpoint.slideshow.macroEnabled.12"), (".ppsx", "application/vnd.openxmlformats-officedocument.presentationml.slideshow"), (".ppt", "application/vnd.ms-powerpoint"), (".pptm", "application/vnd.ms-powerpoint.presentation.macroEnabled.12"), (".pptx", "application/vnd.openxmlformats-officedocument.presentationml.presentation"), (".ps", "application/postscript"), (".svg", "image/svg+xml"), (".swf", "application/x-shockwave-flash"), (".tar", "application/x-tar"), (".tgz", "application/x-gzip"), (".tif", "image/tiff"), (".tiff", "image/tiff"), (".ttf", "application/octet-stream"), (".wav", "audio/x-wav"), (".wmv", "video/x-ms-wmv"), (".xaml", "application/xaml+xml"), (".xap", "application/x-silverlight-app"), (".xhtml", "application/xhtml+xml"), (".xla", "application/vnd.ms-excel"), (".xlam", "application/vnd.ms-excel.addin.macroEnabled.12"), (".xls", "application/vnd.ms-excel"), (".xlsb", "application/vnd.ms-excel.sheet.binary.macroEnabled.12"), (".xlsm", "application/vnd.ms-excel.sheet.macroEnabled.12"), (".xlsx", "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"), (".xlt", "application/vnd.ms-excel"), (".xltm", "application/vnd.ms-excel.template.macroEnabled.12"), (".xltx", "application/vnd.openxmlformats-officedocument.spreadsheetml.template"), (".xml", "text/xml"), (".xsl", "text/xml"), (".zip", "application/zip") ] data MyError = NotModified | Forbidden | NotFound | BadMethod | BadRange deriving (Show, Typeable) instance Exception MyError outputMyError :: MyError -> CGI CGIResult outputMyError NotModified = setStatus 304 "Not Modified" >> outputNothing outputMyError Forbidden = outputError 403 "Forbidden" [] outputMyError NotFound = outputError 404 "Not Found" [] outputMyError BadMethod = outputError 405 "Method Not Allowed" [] outputMyError BadRange = outputError 416 "Requested Range Not Satisfiable" [] checkExtension :: FilePath -> CGI () checkExtension file = do let (base, ext) = splitExtension file ext' <- case M.lookup (map toLower ext) encodings of Nothing -> return ext Just e -> do setHeader "Content-Encoding" e return $ takeExtension base case M.lookup (map toLower ext') types of Nothing -> throw Forbidden Just t -> setHeader "Content-Type" t checkMethod :: CGI CGIResult -> CGI CGIResult checkMethod rOutput = do m <- requestMethod case m of "HEAD" -> rOutput >> outputNothing "GET" -> rOutput "POST" -> rOutput _ -> throw BadMethod httpDate :: String httpDate = "%a, %d %b %Y %H:%M:%S %Z" formatHTTPDate :: EpochTime -> String formatHTTPDate = formatTime defaultTimeLocale httpDate . posixSecondsToUTCTime . realToFrac parseHTTPDate :: String -> Maybe EpochTime parseHTTPDate = (fromInteger . floor . utcTimeToPOSIXSeconds <$>) . parseTime defaultTimeLocale httpDate checkModified :: EpochTime -> CGI () checkModified mTime = do setHeader "Last-Modified" $ formatHTTPDate mTime (requestHeader "If-Modified-Since" >>=) $ maybe (return ()) $ \ims -> when (parseHTTPDate ims >= Just mTime) $ throw NotModified checkIfRange :: EpochTime -> CGI (Maybe ()) checkIfRange mTime = do (requestHeader "If-Range" >>=) $ maybe (return $ Just ()) $ \ir -> return $ if parseHTTPDate ir == Just mTime then Just () else Nothing parseRange :: String -> FileOffset -> Maybe (FileOffset, FileOffset) parseRange (splitAt 6 -> ("bytes=", '-':(readDec -> [(len, "")]))) size = Just (max 0 (size - len), size - 1) parseRange (splitAt 6 -> ("bytes=", readDec -> [(a, "-")])) size = Just (a, size - 1) parseRange (splitAt 6 -> ("bytes=", readDec -> [(a, '-':(readDec -> [(b, "")]))])) size = Just (a, min (size - 1) b) parseRange _ _ = Nothing checkRange :: EpochTime -> FileOffset -> CGI (Maybe (FileOffset, FileOffset)) checkRange mTime size = do setHeader "Accept-Ranges" "bytes" (requestHeader "Range" >>=) $ maybe (return Nothing) $ \range -> do (checkIfRange mTime >>=) $ maybe (return Nothing) $ \() -> do case parseRange range size of Just (a, b) | a <= b -> return $ Just (a, b) Just _ -> throw BadRange Nothing -> return Nothing outputAll :: Handle -> FileOffset -> CGI CGIResult outputAll h size = do setHeader "Content-Length" $ show size outputFPS =<< liftIO (B.hGetContents h) -- | Lazily read a given number of bytes from the handle into a -- 'ByteString', then close the handle. hGetClose :: Handle -> Int64 -> IO B.ByteString hGetClose h len = do contents <- B.hGetContents h end <- unsafeInterleaveIO (hClose h >> return B.empty) return (B.append (B.take len contents) end) outputRange :: Handle -> FileOffset -> Maybe (FileOffset, FileOffset) -> CGI CGIResult outputRange h size Nothing = outputAll h size outputRange h size (Just (a, b)) = do let len = b - a + 1 setStatus 206 "Partial Content" setHeader "Content-Range" $ "bytes " ++ show a ++ "-" ++ show b ++ "/" ++ show size setHeader "Content-Length" $ show len liftIO $ hSeek h AbsoluteSeek (fromIntegral a) outputFPS =<< liftIO (hGetClose h (fromIntegral len)) serveFile :: FilePath -> CGI CGIResult serveFile file = (`catch` outputMyError) $ do checkExtension file checkMethod $ do let handleOpenError e = if isDoesNotExistError e then throw NotFound else if isPermissionError e then throw Forbidden else throw e h <- liftIO (openBinaryFile file ReadMode) `catch` handleOpenError (`onException` liftIO (hClose h)) $ do status <- liftIO $ hGetStatus h let mTime = modificationTime status size = fileSize status checkModified mTime range <- checkRange mTime size outputRange h size range main :: IO () main = runCGI $ handleErrors $ serveFile =<< pathTranslated