diff --git a/FileManipCompat.cabal b/FileManipCompat.cabal --- a/FileManipCompat.cabal +++ b/FileManipCompat.cabal @@ -1,29 +1,27 @@ Name: FileManipCompat -Version: 0.13 +Version: 0.14 License: BSD3 License-File: LICENSE Author: Bryan O'Sullivan Maintainer: Thomas Hartman -Synopsis: Port of Find function of FileManip lib for use on windows systems +Synopsis: Expressive file and directory manipulation for Haskell. Category: System Description: A Haskell library for working with files and directories. Includes code for pattern matching, finding files, modifying file contents, and more. -Build-type: Simple Cabal-version: >= 1.6 +build-type: Simple Extra-Source-Files: README -homepage: http://patch-tag.com/tphyahoo/r/tphyahoo/FileManipCompat -Flag base4 - Description: Choose the even newer, even smaller, split-up base package. +Flag splitBase + Description: Choose the new, split-up base package. + Library - Build-Depends: bytestring, directory, filepath, mtl, unix-compat, extensible-exceptions - if flag(base4) - Build-Depends: base >= 4 && < 5 + if flag(splitBase) + Build-Depends: base <5, bytestring, directory, filepath, mtl, unix-compat else - Build-Depends: base < 4 + Build-Depends: base <4, filepath, mtl, unix-compat - GHC-Options: -Wall + GHC-Options: -Wall Exposed-Modules: System.FilePath.FindCompat - diff --git a/System/FilePath/FindCompat.hs b/System/FilePath/FindCompat.hs --- a/System/FilePath/FindCompat.hs +++ b/System/FilePath/FindCompat.hs @@ -1,20 +1,126 @@ {-# LANGUAGE GeneralizedNewtypeDeriving #-} --- from happstack-util/src/Happstack/Util/FileManip.hs, --- which was derived from FileManip package, which only works on unix. --- happstack port works on windows as well. --- repackage here as standalone to remove dependency on happstack, for immediate use with HStringTemplateHelpers. -module System.FilePath.FindCompat where +-- | +-- Module: System.FilePath.Find +-- Copyright: Bryan O'Sullivan +-- License: BSD3 +-- Maintainer: Bryan O'Sullivan +-- Stability: unstable +-- Portability: Unix-like systems (requires newtype deriving) +-- +-- This module provides functions for traversing a filesystem +-- hierarchy. The 'find' function generates a lazy list of matching +-- files, while 'fold' performs a left fold. +-- +-- Both 'find' and 'fold' allow fine control over recursion, using the +-- 'FindClause' type. This type is also used to pre-filter the results +-- returned by 'find'. +-- +-- The 'FindClause' type lets you write filtering and recursion +-- control expressions clearly and easily. +-- +-- For example, this clause matches C source files. +-- +-- @ +-- 'extension' '==?' \".c\" '||?' 'extension' '==?' \".h\" +-- @ +-- +-- Because 'FindClause' is a monad, you can use the usual monad +-- machinery to, for example, lift pure functions into it. +-- +-- Here's a clause that will return 'False' for any file whose +-- directory name contains the word @\"temp\"@. +-- +-- @ +-- (isInfixOf \"temp\") \`liftM\` 'directory' +-- @ -import qualified System.PosixCompat.Files as F -import Control.Monad.State -import qualified Control.Exception.Extensible as E -import System.IO +module System.FilePath.FindCompat ( + FileInfo(..) + , FileType(..) + , FindClause + , FilterPredicate + , RecursionPredicate + + -- * Simple entry points + , find + , fold + + -- * More expressive entry points + , findWithHandler + , foldWithHandler + + -- * Helper functions + , evalClause + , statusType + , liftOp + + -- * Combinators for controlling recursion and filtering behaviour + , filePath + , fileStatus + , depth + , fileInfo + + , always + , extension + , directory + , fileName + + , fileType + + , contains + + -- ** Combinator versions of 'F.FileStatus' functions from "System.Posix.Files" + -- $statusFunctions + + , deviceID + , fileID + , fileOwner + , fileGroup + , fileSize + , linkCount + , specialDeviceID + , fileMode + , accessTime + , modificationTime + , statusChangeTime + + -- *** Convenience combinators for file status + , filePerms + , anyPerms + + -- ** Combinators that operate on symbolic links + , readLink + , followStatus + + -- ** Common binary operators, lifted as combinators + -- $binaryOperators + --, (~~?) + --, (/~?) + , (==?) + , (/=?) + , (>?) + , (=?) + , (<=?) + , (.&.?) + + -- ** Combinators for gluing clauses together + , (&&?) + , (||?) + ) where + +import Control.Monad (foldM, forM, liftM, liftM2) +import Control.Monad.State (State(..), evalState) +import Data.Bits (Bits, (.&.)) import Data.List (sort) import System.Directory (getDirectoryContents) -import System.IO.Unsafe (unsafeInterleaveIO) -import System.FilePath (()) -import Data.Bits (Bits, (.&.)) +import System.FilePath ((), takeDirectory, takeExtension, takeFileName) +import System.IO (hPutStrLn, stderr) +import System.IO.Unsafe (unsafeInterleaveIO, unsafePerformIO) +import qualified Control.Exception as E +import qualified System.PosixCompat.Files as F +import qualified System.PosixCompat.Types as T -- | Information collected during the traversal of a directory. data FileInfo = FileInfo @@ -23,42 +129,13 @@ , infoDepth :: Int -- ^ current recursion depth , infoStatus :: F.FileStatus -- ^ status of file } deriving (Eq) -instance Eq F.FileStatus where - a == b = F.deviceID a == F.deviceID b && F.fileID a == F.fileID b -data FileType = BlockDevice - | CharacterDevice - | NamedPipe - | RegularFile - | Directory - | SymbolicLink - | Socket - | Unknown - deriving (Eq, Ord, Show) --- | Return the type of file currently being visited. --- --- Example: --- --- @ --- 'fileType' '==?' 'RegularFile' --- @ -fileType :: FindClause FileType -fileType = statusType `liftM` fileStatus +instance Eq F.FileStatus where + a == b = F.deviceID a == F.deviceID b && + F.fileID a == F.fileID b --- | Return the type of a file. This is much more useful for case --- analysis than the usual functions on 'F.FileStatus' values. -statusType :: F.FileStatus -> FileType -statusType st | F.isBlockDevice st = BlockDevice -statusType st | F.isCharacterDevice st = CharacterDevice -statusType st | F.isNamedPipe st = NamedPipe -statusType st | F.isRegularFile st = RegularFile -statusType st | F.isDirectory st = Directory -statusType st | F.isSymbolicLink st = SymbolicLink -statusType st | F.isSocket st = Socket -statusType _ = Unknown - -- | Construct a 'FileInfo' value. mkFI :: FilePath -> Int -> F.FileStatus -> FileInfo @@ -99,11 +176,22 @@ -- | Return the current 'FileInfo'. fileInfo :: FindClause FileInfo + fileInfo = mkFindClause $ \st -> (st, st) +-- | Return the name of the file being visited. +filePath :: FindClause FilePath +filePath = infoPath `liftM` fileInfo + +-- | Return the current recursion depth. +depth :: FindClause Int + +depth = infoDepth `liftM` fileInfo + -- | Return the 'F.FileStatus' for the current file. fileStatus :: FindClause F.FileStatus + fileStatus = infoStatus `liftM` fileInfo type FilterPredicate = FindClause Bool @@ -123,27 +211,27 @@ -- matching the given 'FilterPredicate'. Any errors that occur are -- dealt with by the given handler. findWithHandler :: - (FilePath -> E.SomeException -> IO [FilePath]) -- ^ error handler + (FilePath -> E.Exception -> IO [FilePath]) -- ^ error handler -> RecursionPredicate -- ^ control recursion into subdirectories -> FilterPredicate -- ^ decide whether a file appears in the result -> FilePath -- ^ directory to start searching -> IO [FilePath] -- ^ files that matched the 'FilterPredicate' -findWithHandler errHandler recurse filt path = +findWithHandler errHandler recurse filter path = E.handle (errHandler path) $ F.getSymbolicLinkStatus path >>= visit path 0 - where visit path' depth st = - if F.isDirectory st && evalFI recurse path' depth st - then unsafeInterleaveIO (traverse path' (succ depth) st) - else filterPath path' depth st [] + where visit path depth st = + if F.isDirectory st && evalFI recurse path depth st + then unsafeInterleaveIO (traverse path (succ depth) st) + else filterPath path depth st [] traverse dir depth dirSt = do names <- E.catch (getDirContents dir) (errHandler dir) filteredPaths <- forM names $ \name -> do - let path' = dir name + let path = dir name unsafeInterleaveIO $ E.handle (errHandler path) - (F.getSymbolicLinkStatus path' >>= visit path' depth) + (F.getSymbolicLinkStatus path >>= visit path depth) filterPath dir depth dirSt (concat filteredPaths) - filterPath path' depth st result = - return $ if evalFI filt path' depth st + filterPath path depth st result = + return $ if evalFI filter path depth st then path:result else result @@ -160,16 +248,237 @@ where warnOnError path err = hPutStrLn stderr (path ++ ": " ++ show err) >> return [] +-- | Search a directory recursively, with recursion controlled by a +-- 'RecursionPredicate'. Fold over all files found. Any errors that +-- occur are dealt with by the given handler. The fold is strict, and +-- run from \"left\" to \"right\", so the folded function should be +-- strict in its left argument to avoid space leaks. If you need a +-- right-to-left fold, use 'foldr' on the result of 'findWithHandler' +-- instead. +foldWithHandler + :: (FilePath -> a -> E.Exception -> IO a) -- ^ error handler + -> RecursionPredicate -- ^ control recursion into subdirectories + -> (a -> FileInfo -> a) -- ^ function to fold with + -> a -- ^ seed value for fold + -> FilePath -- ^ directory to start searching + -> IO a -- ^ final value after folding + +foldWithHandler errHandler recurse f state path = + E.handle (errHandler path state) $ + F.getSymbolicLinkStatus path >>= visit state path 0 + where visit state path depth st = + if F.isDirectory st && evalFI recurse path depth st + then traverse state path (succ depth) st + else let state' = f state (mkFI path depth st) + in state' `seq` return state' + traverse state dir depth dirSt = E.handle (errHandler dir state) $ + getDirContents dir >>= + let state' = f state (mkFI dir depth dirSt) + in state' `seq` flip foldM state' (\state name -> + E.handle (errHandler dir state) $ + let path = dir name + in F.getSymbolicLinkStatus path >>= visit state path depth) + +-- | Search a directory recursively, with recursion controlled by a +-- 'RecursionPredicate'. Fold over all files found. Any errors that +-- occur are ignored, with warnings printed to 'stderr'. The fold +-- function is run from \"left\" to \"right\", so it should be strict +-- in its left argument to avoid space leaks. If you need a +-- right-to-left fold, use 'foldr' on the result of 'findWithHandler' +-- instead. +fold :: RecursionPredicate + -> (a -> FileInfo -> a) + -> a + -> FilePath + -> IO a + +fold = foldWithHandler warnOnError + where warnOnError path a err = + hPutStrLn stderr (path ++ ": " ++ show err) >> return a + -- | Unconditionally return 'True'. always :: FindClause Bool always = return True --- | Return the name of the file being visited. -filePath :: FindClause FilePath +-- | Return the file name extension. +-- +-- Example: +-- +-- @ +-- 'extension' \"foo\/bar.txt\" => \".txt\" +-- @ +extension :: FindClause FilePath +extension = takeExtension `liftM` filePath -filePath = infoPath `liftM` fileInfo +-- | Return the file name, without the directory name. +-- +-- What this means in practice: +-- +-- @ +-- 'fileName' \"foo\/bar.txt\" => \"bar.txt\" +-- @ +-- +-- Example: +-- +-- @ +-- 'fileName' '==?' \"init.c\" +-- @ +fileName :: FindClause FilePath +fileName = takeFileName `liftM` filePath +-- | Return the directory name, without the file name. +-- +-- What this means in practice: +-- +-- @ +-- 'directory' \"foo\/bar.txt\" => \"foo\" +-- @ +-- +-- Example in a clause: +-- +-- @ +-- let hasSuffix = 'liftOp' 'isSuffixOf' +-- in directory \`hasSuffix\` \"tests\" +-- @ +directory :: FindClause FilePath +directory = takeDirectory `liftM` filePath +-- | Run the given action in the 'IO' monad (using 'unsafePerformIO') +-- if the current file is a symlink. Hide errors by wrapping results +-- in the 'Maybe' monad. +withLink :: (FilePath -> IO a) -> FindClause (Maybe a) + +withLink f = do + path <- filePath + st <- fileStatus + return $ if F.isSymbolicLink st + then unsafePerformIO $ E.handle (const (return Nothing)) $ + Just `liftM` f path + else Nothing + +-- | If the current file is a symbolic link, return 'Just' the target +-- of the link, otherwise 'Nothing'. +readLink :: FindClause (Maybe FilePath) + +readLink = withLink F.readSymbolicLink + +-- | If the current file is a symbolic link, return 'Just' the status +-- of the ultimate endpoint of the link. Otherwise (including in the +-- case of an error), return 'Nothing'. +-- +-- Example: +-- +-- @ +-- 'statusType' \`liftM\` 'followStatus' '==?' 'RegularFile' +-- @ +followStatus :: FindClause (Maybe F.FileStatus) + +followStatus = withLink F.getFileStatus + +data FileType = BlockDevice + | CharacterDevice + | NamedPipe + | RegularFile + | Directory + | SymbolicLink + | Socket + | Unknown + deriving (Eq, Ord, Show) + +-- | Return the type of file currently being visited. +-- +-- Example: +-- +-- @ +-- 'fileType' '==?' 'RegularFile' +-- @ +fileType :: FindClause FileType + +fileType = statusType `liftM` fileStatus + +-- | Return the type of a file. This is much more useful for case +-- analysis than the usual functions on 'F.FileStatus' values. +statusType :: F.FileStatus -> FileType + +statusType st | F.isBlockDevice st = BlockDevice +statusType st | F.isCharacterDevice st = CharacterDevice +statusType st | F.isNamedPipe st = NamedPipe +statusType st | F.isRegularFile st = RegularFile +statusType st | F.isDirectory st = Directory +statusType st | F.isSymbolicLink st = SymbolicLink +statusType st | F.isSocket st = Socket +statusType _ = Unknown + +-- $statusFunctions +-- +-- These are simply lifted versions of the 'F.FileStatus' accessor +-- functions in the "System.Posix.Files" module. The definitions all +-- have the following form: +-- +-- @ +-- 'deviceID' :: 'FindClause' "System.Posix.Types".DeviceID +-- 'deviceID' = "System.Posix.Files".deviceID \`liftM\` 'fileStatus' +-- @ + +deviceID :: FindClause T.DeviceID +deviceID = F.deviceID `liftM` fileStatus + +fileID :: FindClause T.FileID +fileID = F.fileID `liftM` fileStatus + +fileOwner :: FindClause T.UserID +fileOwner = F.fileOwner `liftM` fileStatus + +fileGroup :: FindClause T.GroupID +fileGroup = F.fileGroup `liftM` fileStatus + +fileSize :: FindClause T.FileOffset +fileSize = F.fileSize `liftM` fileStatus + +linkCount :: FindClause T.LinkCount +linkCount = F.linkCount `liftM` fileStatus + +specialDeviceID :: FindClause T.DeviceID +specialDeviceID = F.specialDeviceID `liftM` fileStatus + +fileMode :: FindClause T.FileMode +fileMode = F.fileMode `liftM` fileStatus + +-- | Return the permission bits of the 'T.FileMode'. +filePerms :: FindClause T.FileMode +filePerms = (.&. 0777) `liftM` fileMode + +-- | Return 'True' if any of the given permission bits is set. +-- +-- Example: +-- +-- @ +-- 'anyPerms' 0444 +-- @ +anyPerms :: T.FileMode + -> FindClause Bool +anyPerms m = filePerms >>= \p -> return (p .&. m /= 0) + +accessTime :: FindClause T.EpochTime +accessTime = F.accessTime `liftM` fileStatus + +modificationTime :: FindClause T.EpochTime +modificationTime = F.modificationTime `liftM` fileStatus + +statusChangeTime :: FindClause T.EpochTime +statusChangeTime = F.statusChangeTime `liftM` fileStatus + +-- | Return 'True' if the given path exists, relative to the current +-- file. For example, if @\"foo\"@ is being visited, and you call +-- contains @\"bar\"@, this combinator will return 'True' if +-- @\"foo\/bar\"@ exists. +contains :: FilePath -> FindClause Bool +contains p = do + d <- filePath + return $ unsafePerformIO $ + E.handle (const (return False)) $ + F.getFileStatus (d p) >> return True + -- | Lift a binary operator into the 'FindClause' monad, so that it -- becomes a combinator. The left hand side of the combinator should -- be a @'FindClause' a@, while the right remains a normal value of @@ -187,6 +496,18 @@ -- -- @('==?') = 'liftOp' (==)@ +-- | Return 'True' if the current file's name matches the given +-- 'GlobPattern'. +{-(~~?) :: FindClause FilePath -> GlobPattern -> FindClause Bool +(~~?) = liftOp (~~) +infix 4 ~~? + +-- | Return 'True' if the current file's name does not match the given +-- 'GlobPattern'. +(/~?) :: FindClause FilePath -> GlobPattern -> FindClause Bool +(/~?) = liftOp (/~) +infix 4 /~? +-} (==?) :: Eq a => FindClause a -> a -> FindClause Bool (==?) = liftOp (==)