{- hpodder component Copyright (C) 2006 John Goerzen This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA -} {- | Module : DownloadQueue Copyright : Copyright (C) 2006 John Goerzen License : GNU GPL, version 2 or above Maintainer : John Goerzen Stability : provisional Portability: portable Written by John Goerzen, jgoerzen\@complete.org -} module DownloadQueue(DownloadEntry(..), DownloadQueue(..), DLAction(..), easyDownloads, runDownloads ) where import Download import System.Cmd.Utils import Data.Maybe.Utils import System.Posix.Process import Config import System.Log.Logger import Text.Printf import System.Exit import System.IO import System.Directory import System.Posix.Files import System.Posix.Signals import Data.Hash.MD5 import Data.Progress.Tracker import Data.Progress.Meter import Data.Quantity import Network.URI import Data.List import Control.Concurrent.MVar import Control.Concurrent import Data.Char import Control.Monad(when) d = debugM "downloadqueue" i = infoM "downloadqueue" data DownloadEntry a = DownloadEntry {dlurl :: String, dlname :: String, usertok :: a, dlprogress :: Progress} data DownloadQueue a = DownloadQueue {pendingHosts :: [(String, [DownloadEntry a])], -- activeDownloads :: (DownloadEntry, DownloadTok), basePath :: FilePath, allowResume :: Bool, callbackFunc :: (DownloadEntry a -> DLAction -> IO ()), completedDownloads :: [(DownloadEntry a, DownloadTok, Result)]} data DLAction = DLStarted DownloadTok | DLEnded (DownloadTok, ProcessStatus, Result, String) deriving (Eq, Show) groupByHost :: [DownloadEntry a] -> [(String, [DownloadEntry a])] groupByHost dllist = combineGroups . groupBy (\(host1, _) (host2, _) -> host1 == host2) . sortBy sortfunc . map (\(x, y) -> (map toLower x, y)) . -- lowercase the hostnames map conv $ dllist where sortfunc (a, _) (b, _) = compare a b conv de = case parseURI (dlurl de) of Nothing -> ("", de) Just x -> case uriAuthority x of Nothing -> ("", de) Just ua -> (uriRegName ua, de) combineGroups :: [[(String, DownloadEntry a)]] -> [(String, [DownloadEntry a])] combineGroups [] = [] combineGroups (x:xs) = (fst . head $ x, map snd x) : combineGroups xs easyDownloads :: String -- ^ Name for tracker -> IO FilePath -- ^ Function to get base dir -> Bool -- ^ Allow resuming -> (Progress -> IO [DownloadEntry a]) -- ^ Function to get DLentries -> (Progress -> ProgressMeter -> DownloadEntry a -> DownloadTok -> IO ()) -- ^ Callback when downloads starts -> (Progress -> ProgressMeter -> DownloadEntry a -> DownloadTok -> ProcessStatus -> Result -> IO ()) -- ^ Callback that gets called after the download is complete -> IO () easyDownloads ptname bdfunc allowresume getentryfunc procStart procFinish = do maxthreads <- getMaxThreads progressinterval <- getProgressInterval basedir <- bdfunc pt <- newProgress ptname 0 meter <- newMeter pt "B" 80 (renderNums binaryOpts 0) meterthread <- autoDisplayMeter meter progressinterval (displayMeter stdout) dlentries <- getentryfunc pt runDownloads (callback pt meter) basedir allowresume dlentries maxthreads killAutoDisplayMeter meter meterthread finishP pt displayMeter stdout meter putStrLn "" where callback pt meter dlentry (DLStarted dltok) = do addComponent meter (dlprogress dlentry) procStart pt meter dlentry dltok callback pt meter dlentry (DLEnded (dltok, status, result, msg)) = do removeComponent meter (dlname dlentry) when (msg /= "") (writeMeterString stderr meter $ " *** " ++ dlname dlentry ++ ": Message on " ++ tokurl dltok ++ ":\n" ++ msg ++ "\n") procFinish pt meter dlentry dltok status result finishP (dlprogress dlentry) runDownloads :: (DownloadEntry a -> DLAction -> IO ()) -> -- Callback when a download starts or stops FilePath -> -- Base path Bool -> -- Whether or not to allow resume [DownloadEntry a] -> -- Items to download Int -> -- Max number of download threads IO [(DownloadEntry a, DownloadTok, Result)] -- The completed DLs runDownloads callbackfunc basefp resumeOK delist maxthreads = do oldsigs <- blocksignals --print (map (\(h, el) -> (h, map dlurl el)) $ groupByHost delist) dqmvar <- newMVar $ DownloadQueue {pendingHosts = groupByHost delist, completedDownloads = [], basePath = basefp, allowResume = resumeOK, callbackFunc = callbackfunc} semaphore <- newQSem 0 -- Used by threads to signal they're done mapM_ (\_ -> forkIO (childthread dqmvar semaphore)) [1..maxthreads] mapM_ (\_ -> waitQSem semaphore) [1..maxthreads] restoresignals oldsigs withMVar dqmvar (\dq -> return (completedDownloads dq)) childthread :: MVar (DownloadQueue a) -> QSem -> IO () childthread dqmvar semaphore = do workdata <- getworkdata if length(workdata) == 0 then signalQSem semaphore -- We're done! else do processChildWorkData workdata childthread dqmvar semaphore -- And look for more hosts where getworkdata = modifyMVar dqmvar $ \dq -> do case pendingHosts dq of [] -> return (dq, []) (x:xs) -> return (dq {pendingHosts = xs}, snd x) getProcessStatusWithDelay pid = do status <- getProcessStatus False False pid case status of Nothing -> do threadDelay 1000000 getProcessStatusWithDelay pid Just x -> return x processChildWorkData [] = return [] processChildWorkData (x:xs) = do (basefp, resumeOK, callback) <- withMVar dqmvar (\dq -> return (basePath dq, allowResume dq, callbackFunc dq)) dltok <- startGetURL (dlurl x) basefp resumeOK callback x (DLStarted dltok) status <- getProcessStatusWithDelay (tokpid dltok) result <- finishGetURL dltok status messages <- readFile (tokpath dltok ++ ".msg") -- Add to the completed DLs list. Also do callback here -- so it's within the lock. Handy to prevent simultaneous -- DB updates. modifyMVar_ dqmvar $ \dq -> do callback x (DLEnded (dltok, status, result, messages)) -- Delete the messages file now that we don't -- care about it anymore catch (removeFile (tokpath dltok ++ ".msg")) (\_ -> return ()) return (dq {completedDownloads = (x, dltok, result) : completedDownloads dq}) processChildWorkData xs -- Do the next one blocksignals = do let sigset = addSignal sigCHLD emptySignalSet oldset <- getSignalMask blockSignals sigset return oldset restoresignals = setSignalMask