import System.Environment ( getArgs, getProgName, getEnv )
import System.IO
import System.IO.Error (try)
-import Data.List ( isPrefixOf, isSuffixOf, intersperse, sortBy, nub,
- unfoldr, break )
-#if __GLASGOW_HASKELL__ > 604
-import Data.List ( isInfixOf )
-#else
-import Data.List ( tails )
-#endif
+import Data.List
import Control.Concurrent
#ifdef mingw32_HOST_OS
import System.Posix
#endif
-import IO ( isPermissionError, isDoesNotExistError )
+import IO ( isPermissionError )
#if defined(GLOB)
import System.Process(runInteractiveCommand)
| FlagSimpleOutput
| FlagNamesOnly
| FlagIgnoreCase
+ | FlagNoUserDb
deriving Eq
flags :: [OptDescr Flag]
"use the specified package config file",
Option [] ["global-conf"] (ReqArg FlagGlobalConfig "FILE")
"location of the global package config",
+ Option [] ["no-user-package-conf"] (NoArg FlagNoUserDb)
+ "never read the user package database",
Option [] ["force"] (NoArg FlagForce)
"ignore missing dependencies, directories, and libraries",
Option [] ["force-files"] (NoArg FlagForceFiles)
" Extract the specified field of the package description for the\n" ++
" specified package. Accepts comma-separated multiple fields.\n" ++
"\n" ++
+ " $p dump\n" ++
+ " Dump the registered description for every package. This is like\n" ++
+ " \"ghc-pkg describe '*'\", except that it is intended to be used\n" ++
+ " by tools that parse the results, rather than humans.\n" ++
+ "\n" ++
" Substring matching is supported for {module} in find-module and\n" ++
" for {pkg} in list, describe, and field, where a '*' indicates\n" ++
" open substring ends (prefix*, *suffix, *infix*).\n" ++
registerPackage filename cli auto_ghci_libs True force
["unregister", pkgid_str] -> do
pkgid <- readGlobPkgId pkgid_str
- unregisterPackage pkgid cli
+ unregisterPackage pkgid cli force
["expose", pkgid_str] -> do
pkgid <- readGlobPkgId pkgid_str
- exposePackage pkgid cli
+ exposePackage pkgid cli force
["hide", pkgid_str] -> do
pkgid <- readGlobPkgId pkgid_str
- hidePackage pkgid cli
+ hidePackage pkgid cli force
["list"] -> do
listPackages cli Nothing Nothing
["list", pkgid_str] ->
(splitFields fields)
["check"] -> do
checkConsistency cli
+
+ ["dump"] -> do
+ dumpPackages cli
+
[] -> do
die ("missing command\n" ++
usageInfo (usageHeader prog) flags)
type PackageDBName = FilePath
type PackageDB = [InstalledPackageInfo]
-type PackageDBStack = [(PackageDBName,PackageDB)]
+type NamedPackageDB = (PackageDBName, PackageDB)
+type PackageDBStack = [NamedPackageDB]
-- A stack of package databases. Convention: head is the topmost
-- in the stack. Earlier entries override later one.
-getPkgDatabases :: Bool -> [Flag] -> IO PackageDBStack
-getPkgDatabases modify flags = do
+allPackagesInStack :: PackageDBStack -> [InstalledPackageInfo]
+allPackagesInStack = concatMap snd
+
+getPkgDatabases :: Bool -> [Flag] -> IO (PackageDBStack, Maybe PackageDBName)
+getPkgDatabases modify my_flags = do
-- first we determine the location of the global package config. On Windows,
-- this is found relative to the ghc-pkg.exe binary, whereas on Unix the
-- location is passed to the binary using the --global-config flag by the
-- wrapper script.
let err_msg = "missing --global-conf option, location of global package.conf unknown\n"
global_conf <-
- case [ f | FlagGlobalConfig f <- flags ] of
+ case [ f | FlagGlobalConfig f <- my_flags ] of
[] -> do mb_dir <- getExecDir "/bin/ghc-pkg.exe"
case mb_dir of
Nothing -> die err_msg
- Just dir -> return (dir </> "package.conf")
+ Just dir ->
+ do let path1 = dir </> "package.conf"
+ path2 = dir </> ".." </> ".." </> ".."
+ </> "inplace-datadir"
+ </> "package.conf"
+ exists1 <- doesFileExist path1
+ exists2 <- doesFileExist path2
+ if exists1 then return path1
+ else if exists2 then return path2
+ else die "Can't find package.conf"
fs -> return (last fs)
let global_conf_dir = global_conf ++ ".d"
, isSuffixOf ".conf" file]
else return []
- -- get the location of the user package database, and create it if necessary
- appdir <- getAppUserDataDirectory "ghc"
+ let no_user_db = FlagNoUserDb `elem` my_flags
- let
- subdir = targetARCH ++ '-':targetOS ++ '-':Version.version
- archdir = appdir </> subdir
- user_conf = archdir </> "package.conf"
- user_exists <- doesFileExist user_conf
+ -- get the location of the user package database, and create it if necessary
+ -- getAppUserDataDirectory can fail (e.g. if $HOME isn't set)
+ appdir <- try $ getAppUserDataDirectory "ghc"
+
+ mb_user_conf <-
+ if no_user_db then return Nothing else
+ case appdir of
+ Right dir -> do
+ let subdir = targetARCH ++ '-':targetOS ++ '-':Version.version
+ user_conf = dir </> subdir </> "package.conf"
+ user_exists <- doesFileExist user_conf
+ return (Just (user_conf,user_exists))
+ Left _ ->
+ return Nothing
-- If the user database doesn't exist, and this command isn't a
-- "modify" command, then we won't attempt to create or use it.
let sys_databases
- | modify || user_exists = user_conf : global_confs ++ [global_conf]
+ | Just (user_conf,user_exists) <- mb_user_conf,
+ modify || user_exists = user_conf : global_confs ++ [global_conf]
| otherwise = global_confs ++ [global_conf]
e_pkg_path <- try (System.Environment.getEnv "GHC_PACKAGE_PATH")
Right path
| last cs == "" -> init cs ++ sys_databases
| otherwise -> cs
- where cs = splitSearchPath path
+ where cs = parseSearchPath path
-- The "global" database is always the one at the bottom of the stack.
-- This is the database we modify by default.
virt_global_conf = last env_stack
- let db_flags = [ f | Just f <- map is_db_flag flags ]
- where is_db_flag FlagUser = Just user_conf
+ let db_flags = [ f | Just f <- map is_db_flag my_flags ]
+ where is_db_flag FlagUser
+ | Just (user_conf, _user_exists) <- mb_user_conf
+ = Just user_conf
is_db_flag FlagGlobal = Just virt_global_conf
is_db_flag (FlagConfig f) = Just f
is_db_flag _ = Nothing
- final_stack <-
+ (final_stack, to_modify) <-
if not modify
then -- For a "read" command, we use all the databases
-- specified on the command line. If there are no
-- command-line flags specifying databases, the default
-- is to use all the ones we know about.
- if null db_flags then return env_stack
- else return (reverse (nub db_flags))
+ if null db_flags then return (env_stack, Nothing)
+ else return (reverse (nub db_flags), Nothing)
else let
-- For a "modify" command, treat all the databases as
-- a stack, where we are modifying the top one, but it
-- stack, unless any of them are present in the stack
-- already.
flag_stack = filter (`notElem` env_stack)
- [ f | FlagConfig f <- reverse flags ]
+ [ f | FlagConfig f <- reverse my_flags ]
++ env_stack
- modifying f
- | f `elem` flag_stack = return (dropWhile (/= f) flag_stack)
- | otherwise = die ("requesting modification of database:\n\t" ++ f ++ "\n\twhich is not in the database stack.")
+ -- the database we actually modify is the one mentioned
+ -- rightmost on the command-line.
+ to_modify = if null db_flags
+ then Just virt_global_conf
+ else Just (last db_flags)
in
- if null db_flags
- then modifying virt_global_conf
- else modifying (head db_flags)
+ return (flag_stack, to_modify)
db_stack <- mapM readParseDatabase final_stack
- return db_stack
+ return (db_stack, to_modify)
readParseDatabase :: PackageDBName -> IO (PackageDBName,PackageDB)
readParseDatabase filename = do
- str <- readFile filename `Exception.catch` \_ -> return emptyPackageConfig
+ str <- readFile filename `catchIO` \_ -> return emptyPackageConfig
let packages = map convertPackageInfoIn $ read str
Exception.evaluate packages
- `Exception.catch` \e->
+ `catchError` \e->
die ("error while parsing " ++ filename ++ ": " ++ show e)
return (filename,packages)
-> Bool -- update
-> Force
-> IO ()
-registerPackage input flags auto_ghci_libs update force = do
- db_stack <- getPkgDatabases True flags
+registerPackage input my_flags auto_ghci_libs update force = do
+ (db_stack, Just to_modify) <- getPkgDatabases True my_flags
let
- db_to_operate_on = my_head "db" db_stack
- db_filename = fst db_to_operate_on
+ db_to_operate_on = my_head "register" $
+ filter ((== to_modify).fst) db_stack
--
-
s <-
case input of
"-" -> do
pkg <- parsePackageInfo expanded
putStrLn "done."
- validatePackageConfig pkg db_stack auto_ghci_libs update force
+ let truncated_stack = dropWhile ((/= to_modify).fst) db_stack
+ -- truncate the stack for validation, because we don't allow
+ -- packages lower in the stack to refer to those higher up.
+ validatePackageConfig pkg truncated_stack auto_ghci_libs update force
let new_details = filter not_this (snd db_to_operate_on) ++ [pkg]
not_this p = package p /= package pkg
- savingOldConfig db_filename $
- writeNewConfig db_filename new_details
+ writeNewConfig to_modify new_details
parsePackageInfo
:: String
-- -----------------------------------------------------------------------------
-- Exposing, Hiding, Unregistering are all similar
-exposePackage :: PackageIdentifier -> [Flag] -> IO ()
+exposePackage :: PackageIdentifier -> [Flag] -> Force -> IO ()
exposePackage = modifyPackage (\p -> [p{exposed=True}])
-hidePackage :: PackageIdentifier -> [Flag] -> IO ()
+hidePackage :: PackageIdentifier -> [Flag] -> Force -> IO ()
hidePackage = modifyPackage (\p -> [p{exposed=False}])
-unregisterPackage :: PackageIdentifier -> [Flag] -> IO ()
-unregisterPackage = modifyPackage (\p -> [])
+unregisterPackage :: PackageIdentifier -> [Flag] -> Force -> IO ()
+unregisterPackage = modifyPackage (\_ -> [])
modifyPackage
:: (InstalledPackageInfo -> [InstalledPackageInfo])
-> PackageIdentifier
-> [Flag]
+ -> Force
-> IO ()
-modifyPackage fn pkgid flags = do
- db_stack <- getPkgDatabases True{-modify-} flags
- let ((db_name, pkgs) : _) = db_stack
- ps <- findPackages [(db_name,pkgs)] (Id pkgid)
- let pids = map package ps
- let new_config = concat (map modify pkgs)
+modifyPackage fn pkgid my_flags force = do
+ (db_stack, Just _to_modify) <- getPkgDatabases True{-modify-} my_flags
+ ((db_name, pkgs), ps) <- fmap head $ findPackagesByDB db_stack (Id pkgid)
+-- let ((db_name, pkgs) : rest_of_stack) = db_stack
+-- ps <- findPackages [(db_name,pkgs)] (Id pkgid)
+ let
+ pids = map package ps
modify pkg
| package pkg `elem` pids = fn pkg
| otherwise = [pkg]
- savingOldConfig db_name $
- writeNewConfig db_name new_config
+ new_config = concat (map modify pkgs)
+
+ let
+ old_broken = brokenPackages (allPackagesInStack db_stack)
+ rest_of_stack = [ (nm, mypkgs)
+ | (nm, mypkgs) <- db_stack, nm /= db_name ]
+ new_stack = (db_name,new_config) : rest_of_stack
+ new_broken = map package (brokenPackages (allPackagesInStack new_stack))
+ newly_broken = filter (`notElem` map package old_broken) new_broken
+ --
+ when (not (null newly_broken)) $
+ dieOrForceAll force ("unregistering " ++ display pkgid ++
+ " would break the following packages: "
+ ++ unwords (map display newly_broken))
+
+ writeNewConfig db_name new_config
-- -----------------------------------------------------------------------------
-- Listing packages
listPackages :: [Flag] -> Maybe PackageArg -> Maybe (String->Bool) -> IO ()
-listPackages flags mPackageName mModuleName = do
- let simple_output = FlagSimpleOutput `elem` flags
- db_stack <- getPkgDatabases False flags
+listPackages my_flags mPackageName mModuleName = do
+ let simple_output = FlagSimpleOutput `elem` my_flags
+ (db_stack, _) <- getPkgDatabases False my_flags
let db_stack_filtered -- if a package is given, filter out all other packages
| Just this <- mPackageName =
map (\(conf,pkgs) -> (conf, filter (this `matchesPkg`) pkgs))
match `exposedInPkg` pkg = any match (map display $ exposedModules pkg)
- pkg_map = map (\p -> (package p, p)) $ concatMap snd db_stack
+ pkg_map = allPackagesInStack db_stack
show_func = if simple_output then show_simple else mapM_ (show_normal pkg_map)
show_func (reverse db_stack_sorted)
text db_name <> colon $$ nest 4 packages
)
where packages = fsep (punctuate comma (map pp_pkg pkg_confs))
+ broken = map package (brokenPackages pkg_map)
pp_pkg p
- | isBrokenPackage p pkg_map = braces doc
+ | package p `elem` broken = braces doc
| exposed p = doc
| otherwise = parens doc
where doc = text (display (package p))
show_simple db_stack = do
- let showPkg = if FlagNamesOnly `elem` flags then display . pkgName
- else display
+ let showPkg = if FlagNamesOnly `elem` my_flags then display . pkgName
+ else display
pkgs = map showPkg $ sortBy compPkgIdVer $
- map package (concatMap snd db_stack)
+ map package (allPackagesInStack db_stack)
when (not (null pkgs)) $
hPutStrLn stdout $ concat $ intersperse " " pkgs
-- Prints the highest (hidden or exposed) version of a package
latestPackage :: [Flag] -> PackageIdentifier -> IO ()
-latestPackage flags pkgid = do
- db_stack <- getPkgDatabases False flags
+latestPackage my_flags pkgid = do
+ (db_stack, _) <- getPkgDatabases False my_flags
ps <- findPackages db_stack (Id pkgid)
show_pkg (sortBy compPkgIdVer (map package ps))
where
-- Describe
describePackage :: [Flag] -> PackageArg -> IO ()
-describePackage flags pkgarg = do
- db_stack <- getPkgDatabases False flags
+describePackage my_flags pkgarg = do
+ (db_stack, _) <- getPkgDatabases False my_flags
ps <- findPackages db_stack pkgarg
- mapM_ (putStrLn . showInstalledPackageInfo) ps
+ doDump ps
+
+dumpPackages :: [Flag] -> IO ()
+dumpPackages my_flags = do
+ (db_stack, _) <- getPkgDatabases False my_flags
+ doDump (allPackagesInStack db_stack)
+
+doDump :: [InstalledPackageInfo] -> IO ()
+doDump = mapM_ putStrLn . intersperse "---" . map showInstalledPackageInfo
-- PackageId is can have globVersion for the version
findPackages :: PackageDBStack -> PackageArg -> IO [InstalledPackageInfo]
findPackages db_stack pkgarg
- = case [ p | p <- all_pkgs, pkgarg `matchesPkg` p ] of
- [] -> die ("cannot find package " ++ pkg_msg pkgarg)
+ = fmap (concatMap snd) $ findPackagesByDB db_stack pkgarg
+
+findPackagesByDB :: PackageDBStack -> PackageArg
+ -> IO [(NamedPackageDB, [InstalledPackageInfo])]
+findPackagesByDB db_stack pkgarg
+ = case [ (db, matched)
+ | db@(_, pkgs) <- db_stack,
+ let matched = filter (pkgarg `matchesPkg`) pkgs,
+ not (null matched) ] of
+ [] -> die ("cannot find package " ++ pkg_msg pkgarg)
ps -> return ps
where
- all_pkgs = concat (map snd db_stack)
pkg_msg (Id pkgid) = display pkgid
- pkg_msg (Substring pkgpat _) = "matching "++pkgpat
+ pkg_msg (Substring pkgpat _) = "matching " ++ pkgpat
matches :: PackageIdentifier -> PackageIdentifier -> Bool
pid `matches` pid'
-- Field
describeField :: [Flag] -> PackageArg -> [String] -> IO ()
-describeField flags pkgarg fields = do
- db_stack <- getPkgDatabases False flags
+describeField my_flags pkgarg fields = do
+ (db_stack, _) <- getPkgDatabases False my_flags
fns <- toFields fields
ps <- findPackages db_stack pkgarg
let top_dir = takeDirectory (fst (last db_stack))
-- Check: Check consistency of installed packages
checkConsistency :: [Flag] -> IO ()
-checkConsistency flags = do
- db_stack <- getPkgDatabases True flags
+checkConsistency my_flags = do
+ (db_stack, _) <- getPkgDatabases True my_flags
-- check behaves like modify for the purposes of deciding which
-- databases to use, because ordering is important.
- let pkgs = map (\p -> (package p, p)) $ concatMap snd db_stack
- broken_pkgs = do
- (pid, p) <- pkgs
- let broken_deps = missingPackageDeps p pkgs
- guard (not . null $ broken_deps)
- return (pid, broken_deps)
- mapM_ (putStrLn . render . show_func) broken_pkgs
+ let pkgs = allPackagesInStack db_stack
+ broken_pkgs = brokenPackages pkgs
+ broken_ids = map package broken_pkgs
+ broken_why = [ (package p, filter (`elem` broken_ids) (depends p))
+ | p <- broken_pkgs ]
+ mapM_ (putStrLn . render . show_func) broken_why
where
- show_func | FlagSimpleOutput `elem` flags = show_simple
+ show_func | FlagSimpleOutput `elem` my_flags = show_simple
| otherwise = show_normal
show_simple (pid,deps) =
text (display pid) <> colon
text "package" <+> text (display pid) <+> text "has missing dependencies:"
$$ nest 4 (fsep (punctuate comma (map (text . display) deps)))
-missingPackageDeps :: InstalledPackageInfo
- -> [(PackageIdentifier, InstalledPackageInfo)]
- -> [PackageIdentifier]
-missingPackageDeps pkg pkg_map =
- [ d | d <- depends pkg, isNothing (lookup d pkg_map)] ++
- [ d | d <- depends pkg, Just p <- return (lookup d pkg_map),
- isBrokenPackage p pkg_map]
-
-isBrokenPackage :: InstalledPackageInfo -> [(PackageIdentifier, InstalledPackageInfo)] -> Bool
-isBrokenPackage pkg pkg_map
- = not . null $ missingPackageDeps pkg (filter notme pkg_map)
- where notme (p,ipi) = package pkg /= p
- -- remove p from the database when we invoke missingPackageDeps,
- -- because we want mutually recursive groups of package to show up
+
+brokenPackages :: [InstalledPackageInfo] -> [InstalledPackageInfo]
+brokenPackages pkgs = go [] pkgs
+ where
+ go avail not_avail =
+ case partition (depsAvailable avail) not_avail of
+ ([], not_avail') -> not_avail'
+ (new_avail, not_avail') -> go (new_avail ++ avail) not_avail'
+
+ depsAvailable :: [InstalledPackageInfo] -> InstalledPackageInfo
+ -> Bool
+ depsAvailable pkgs_ok pkg = null dangling
+ where dangling = filter (`notElem` pids) (depends pkg)
+ pids = map package pkgs_ok
+
+ -- we want mutually recursive groups of package to show up
-- as broken. (#1750)
-- -----------------------------------------------------------------------------
writeNewConfig filename packages = do
hPutStr stdout "Writing new package config file... "
createDirectoryIfMissing True $ takeDirectory filename
- h <- openFile filename WriteMode `catch` \e ->
- if isPermissionError e
- then die (filename ++ ": you don't have permission to modify this file")
- else ioError e
let shown = concat $ intersperse ",\n "
$ map (show . convertPackageInfoOut) packages
fileContents = "[" ++ shown ++ "\n]"
- hPutStrLn h fileContents
- hClose h
+ writeFileAtomic filename fileContents
+ `catch` \e ->
+ if isPermissionError e
+ then die (filename ++ ": you don't have permission to modify this file")
+ else ioError e
hPutStrLn stdout "done."
-savingOldConfig :: FilePath -> IO () -> IO ()
-savingOldConfig filename io = Exception.block $ do
- hPutStr stdout "Saving old package config file... "
- -- mv rather than cp because we've already done an hGetContents
- -- on this file so we won't be able to open it for writing
- -- unless we move the old one out of the way...
- let oldFile = filename ++ ".old"
- restore_on_error <- catch (renameFile filename oldFile >> return True) $
- \err -> do
- unless (isDoesNotExistError err) $ do
- hPutStrLn stderr (unwords ["Unable to rename", show filename,
- "to", show oldFile])
- ioError err
- return False
- (do hPutStrLn stdout "done."; io)
- `Exception.catch` \e -> do
- hPutStr stdout ("WARNING: an error was encountered while writing "
- ++ "the new configuration.\n")
- -- remove any partially complete new version:
- try (removeFile filename)
- -- and attempt to restore the old one, if we had one:
- when restore_on_error $ do
- hPutStr stdout "Attempting to restore the old configuration... "
- do renameFile oldFile filename
- hPutStrLn stdout "done."
- `catch` \err -> hPutStrLn stdout ("Failed: " ++ show err)
- -- Note the above renameFile sometimes fails on Windows with
- -- "permission denied", I have no idea why --SDM.
- Exception.throwIO e
-
-----------------------------------------------------------------------------
-- Sanity-check a new package config, and automatically build GHCi libs
-- if requested.
checkPackageId pkg
checkDuplicates db_stack pkg update force
mapM_ (checkDep db_stack force) (depends pkg)
+ checkDuplicateDepends force (depends pkg)
mapM_ (checkDir force) (importDirs pkg)
mapM_ (checkDir force) (libraryDirs pkg)
mapM_ (checkDir force) (includeDirs pkg)
name_exists = any (\p -> pkgName (package p) == name) all_pkgs
name = pkgName pkgid
- all_pkgs = concat (map snd db_stack)
+ all_pkgs = allPackagesInStack db_stack
pkgids = map package all_pkgs
+checkDuplicateDepends :: Force -> [PackageIdentifier] -> IO ()
+checkDuplicateDepends force deps
+ | null dups = return ()
+ | otherwise = dieOrForceAll force ("package has duplicate dependencies: " ++
+ unwords (map display dups))
+ where
+ dups = [ p | (p:_:_) <- group (sort deps) ]
+
realVersion :: PackageIdentifier -> Bool
realVersion pkgid = versionBranch (pkgVersion pkgid) /= []
-- expanding environment variables in the package configuration
expandEnvVars :: String -> Force -> IO String
-expandEnvVars str force = go str ""
+expandEnvVars str0 force = go str0 ""
where
go "" acc = return $! reverse acc
go ('$':'{':str) acc | (var, '}':rest) <- break close str
bye s = putStr s >> exitWith ExitSuccess
die :: String -> IO a
-die s = do
+die = dieWith 1
+
+dieWith :: Int -> String -> IO a
+dieWith ec s = do
hFlush stdout
prog <- getProgramName
hPutStrLn stderr (prog ++ ": " ++ s)
- exitWith (ExitFailure 1)
+ exitWith (ExitFailure ec)
dieOrForceAll :: Force -> String -> IO ()
dieOrForceAll ForceAll s = ignoreError s
dieForcible s = die (s ++ " (use --force to override)")
my_head :: String -> [a] -> a
-my_head s [] = error s
-my_head s (x:xs) = x
+my_head s [] = error s
+my_head _ (x : _) = x
-----------------------------------------
-- Cut and pasted from ghc/compiler/main/SysTools
isInfixOf :: (Eq a) => [a] -> [a] -> Bool
isInfixOf needle haystack = any (isPrefixOf needle) (tails haystack)
#endif
+
+catchIO :: IO a -> (Exception.IOException -> IO a) -> IO a
+#if __GLASGOW_HASKELL__ >= 609
+catchIO = Exception.catch
+#else
+catchIO io handler = io `Exception.catch` handler'
+ where handler' (Exception.IOException ioe) = handler ioe
+ handler' e = Exception.throw e
+#endif
+
+#if mingw32_HOST_OS || mingw32_TARGET_OS
+throwIOIO :: Exception.IOException -> IO a
+#if __GLASGOW_HASKELL__ >= 609
+throwIOIO = Exception.throwIO
+#else
+throwIOIO ioe = Exception.throwIO (Exception.IOException ioe)
+#endif
+#endif
+
+catchError :: IO a -> (String -> IO a) -> IO a
+#if __GLASGOW_HASKELL__ >= 609
+catchError io handler = io `Exception.catch` handler'
+ where handler' (Exception.ErrorCall err) = handler err
+#else
+catchError io handler = io `Exception.catch` handler'
+ where handler' (Exception.ErrorCall err) = handler err
+ handler' e = Exception.throw e
+#endif
+
+onException :: IO a -> IO () -> IO a
+#if __GLASGOW_HASKELL__ >= 609
+onException = Exception.onException
+#else
+onException io what = io `Exception.catch` \e -> do what
+ Exception.throw e
+#endif
+
+
+-- copied from Cabal's Distribution.Simple.Utils, except that we want
+-- to use text files here, rather than binary files.
+writeFileAtomic :: FilePath -> String -> IO ()
+writeFileAtomic targetFile content = do
+ (tmpFile, tmpHandle) <- openTempFile targetDir template
+ do hPutStr tmpHandle content
+ hClose tmpHandle
+#if mingw32_HOST_OS || mingw32_TARGET_OS
+ renameFile tmpFile targetFile
+ -- If the targetFile exists then renameFile will fail
+ `catchIO` \err -> do
+ exists <- doesFileExist targetFile
+ if exists
+ then do removeFile targetFile
+ -- Big fat hairy race condition
+ renameFile tmpFile targetFile
+ -- If the removeFile succeeds and the renameFile fails
+ -- then we've lost the atomic property.
+ else throwIOIO err
+#else
+ renameFile tmpFile targetFile
+#endif
+ `onException` do hClose tmpHandle
+ removeFile tmpFile
+ where
+ template = targetName <.> "tmp"
+ targetDir | null targetDir_ = "."
+ | otherwise = targetDir_
+ --TODO: remove this when takeDirectory/splitFileName is fixed
+ -- to always return a valid dir
+ (targetDir_,targetName) = splitFileName targetFile
+
+-- | The function splits the given string to substrings
+-- using 'isSearchPathSeparator'.
+parseSearchPath :: String -> [FilePath]
+parseSearchPath path = split path
+ where
+ split :: String -> [String]
+ split s =
+ case rest' of
+ [] -> [chunk]
+ _:rest -> chunk : split rest
+ where
+ chunk =
+ case chunk' of
+#ifdef mingw32_HOST_OS
+ ('\"':xs@(_:_)) | last xs == '\"' -> init xs
+#endif
+ _ -> chunk'
+
+ (chunk', rest') = break isSearchPathSeparator s