diff --git a/LICENSE b/LICENSE new file mode 100644 --- /dev/null +++ b/LICENSE @@ -0,0 +1,27 @@ +Copyright (c) Bryan O'Sullivan 2007, 2010. + +All rights reserved. + +Redistribution and use in source and binary forms, with or without +modification, are permitted provided that the following conditions +are met: +1. Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. +2. Redistributions in binary form must reproduce the above copyright + notice, this list of conditions and the following disclaimer in the + documentation and/or other materials provided with the distribution. +3. Neither the name of the author nor the names of his contributors + may be used to endorse or promote products derived from this software + without specific prior written permission. + +THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND +ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE +FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +SUCH DAMAGE. diff --git a/README.markdown b/README.markdown new file mode 100644 --- /dev/null +++ b/README.markdown @@ -0,0 +1,26 @@ +# filemanip: expressive file manipulation + +This package provides functions and combinators for searching, +matching, and manipulating files. + + +# Get involved! + +Please report bugs via the +[bitbucket issue tracker](http://bitbucket.org/bos/attoparsec/filemanip). + +Master [Mercurial repository](http://bitbucket.org/bos/filemanip): + +* `hg clone http://bitbucket.org/bos/filemanip` + +There's also a [git mirror](http://github.com/bos/filemanip): + +* `git clone git://github.com/bos/filemanip.git` + +(You can create and contribute changes using either Mercurial or git.) + + +# Authors + +This library is written and maintained by Bryan O'Sullivan, +. diff --git a/Setup.lhs b/Setup.lhs new file mode 100644 --- /dev/null +++ b/Setup.lhs @@ -0,0 +1,3 @@ +#!/usr/bin/env runhaskell +> import Distribution.Simple +> main = defaultMain diff --git a/System/FilePath/Find.hs b/System/FilePath/Find.hs new file mode 100644 --- /dev/null +++ b/System/FilePath/Find.hs @@ -0,0 +1,548 @@ +{-# LANGUAGE GeneralizedNewtypeDeriving, ScopedTypeVariables #-} +{-# OPTIONS_GHC -fno-warn-orphans #-} + +-- | +-- 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' +-- @ + +module System.FilePath.Find ( + 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.Exception +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.FilePath ((), takeDirectory, takeExtension, takeFileName) +import System.FilePath.GlobPattern (GlobPattern, (~~), (/~)) +import System.IO (hPutStrLn, stderr) +import System.IO.Unsafe (unsafeInterleaveIO, unsafePerformIO) +import qualified System.PosixCompat.Files as F +import qualified System.PosixCompat.Types as T +import Prelude hiding (catch) + +-- | Information collected during the traversal of a directory. +data FileInfo = FileInfo + { + infoPath :: FilePath -- ^ file path + , 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 + +-- | Construct a 'FileInfo' value. + +mkFI :: FilePath -> Int -> F.FileStatus -> FileInfo + +mkFI = FileInfo + +-- | Monadic container for file information, allowing for clean +-- construction of combinators. Wraps the 'State' monad, but doesn't +-- allow 'get' or 'put'. +newtype FindClause a = FC { runFC :: State FileInfo a } + deriving (Functor, Monad) + +-- | Run the given 'FindClause' on the given 'FileInfo' and return its +-- result. This can be useful if you are writing a function to pass +-- to 'fold'. +-- +-- Example: +-- +-- @ +-- myFoldFunc :: a -> 'FileInfo' -> a +-- myFoldFunc a i = let useThisFile = 'evalClause' ('fileName' '==?' \"foo\") i +-- in if useThisFile +-- then fiddleWith a +-- else a +-- @ +evalClause :: FindClause a -> FileInfo -> a +evalClause = evalState . runFC + +evalFI :: FindClause a + -> FilePath + -> Int + -> F.FileStatus + -> a +evalFI m p d s = evalClause m (mkFI p d s) + +mkFindClause :: (FileInfo -> (a, FileInfo)) -> FindClause a +mkFindClause = FC . State + +-- | 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 +type RecursionPredicate = FindClause Bool + +-- | List the files in the given directory, sorted, and without \".\" +-- or \"..\". +getDirContents :: FilePath -> IO [FilePath] + +getDirContents dir = (sort . filter goodName) `liftM` getDirectoryContents dir + where goodName "." = False + goodName ".." = False + goodName _ = True + +-- | Search a directory recursively, with recursion controlled by a +-- 'RecursionPredicate'. Lazily return a sorted list of all files +-- matching the given 'FilterPredicate'. Any errors that occur are +-- dealt with by the given handler. +findWithHandler :: + (FilePath -> IOException -> 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 path0 = + handle (errHandler path0) $ F.getSymbolicLinkStatus path0 >>= visit path0 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 [] + traverse dir depth dirSt = do + names <- catch (getDirContents dir) (errHandler dir) + filteredPaths <- forM names $ \name -> do + let path = dir name + unsafeInterleaveIO $ handle (errHandler path) + (F.getSymbolicLinkStatus path >>= visit path depth) + filterPath dir depth dirSt (concat filteredPaths) + filterPath path depth st result = + return $ if evalFI filt path depth st + then path:result + else result + +-- | Search a directory recursively, with recursion controlled by a +-- 'RecursionPredicate'. Lazily return a sorted list of all files +-- matching the given 'FilterPredicate'. Any errors that occur are +-- ignored, with warnings printed to 'stderr'. +find :: 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' + +find = findWithHandler warnOnError + 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 -> IOException -> 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 = + 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 = handle (errHandler dir state) $ + getDirContents dir >>= + let state' = f state (mkFI dir depth dirSt) + in state' `seq` flip foldM state' (\state name -> + 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 file name extension. +-- +-- Example: +-- +-- @ +-- 'extension' \"foo\/bar.txt\" => \".txt\" +-- @ +extension :: FindClause FilePath +extension = takeExtension `liftM` filePath + +-- | 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 $ handle (\(_::IOException) -> 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 $ + handle (\(_::IOException) -> 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 +-- type @a@. +liftOp :: Monad m => (a -> b -> c) -> m a -> b -> m c + +liftOp f a b = a >>= \a' -> return (f a' b) + +-- $binaryOperators +-- +-- These are lifted versions of the most commonly used binary +-- operators. They have the same fixities and associativities as +-- their unlifted counterparts. They are lifted using 'liftOp', like +-- so: +-- +-- @('==?') = '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 (==) +infix 4 ==? + +(/=?) :: Eq a => FindClause a -> a -> FindClause Bool +(/=?) = liftOp (/=) +infix 4 /=? + +(>?) :: Ord a => FindClause a -> a -> FindClause Bool +(>?) = liftOp (>) +infix 4 >? + +( FindClause a -> a -> FindClause Bool +(=?) :: Ord a => FindClause a -> a -> FindClause Bool +(>=?) = liftOp (>=) +infix 4 >=? + +(<=?) :: Ord a => FindClause a -> a -> FindClause Bool +(<=?) = liftOp (<=) +infix 4 <=? + +-- | This operator is useful to check if bits are set in a +-- 'T.FileMode'. +(.&.?) :: Bits a => FindClause a -> a -> FindClause a +(.&.?) = liftOp (.&.) +infixl 7 .&.? + +(&&?) :: FindClause Bool -> FindClause Bool -> FindClause Bool +(&&?) = liftM2 (&&) +infixr 3 &&? + +(||?) :: FindClause Bool -> FindClause Bool -> FindClause Bool +(||?) = liftM2 (||) +infixr 2 ||? diff --git a/System/FilePath/Glob.hs b/System/FilePath/Glob.hs new file mode 100644 --- /dev/null +++ b/System/FilePath/Glob.hs @@ -0,0 +1,73 @@ +{-# LANGUAGE ScopedTypeVariables #-} +-- | +-- Module: System.FilePath.Glob +-- Copyright: Bryan O'Sullivan +-- License: BSD3 +-- Maintainer: Bryan O'Sullivan +-- Stability: unstable +-- Portability: everywhere + +module System.FilePath.Glob ( + namesMatching + ) where + +import Control.Exception +import Control.Monad (forM) +import System.FilePath.GlobPattern ((~~)) +import System.Directory (doesDirectoryExist, doesFileExist, + getCurrentDirectory, getDirectoryContents) +import System.FilePath (dropTrailingPathSeparator, splitFileName, ()) +import System.IO.Unsafe (unsafeInterleaveIO) + +-- | Return a list of names matching a glob pattern. The list is +-- generated lazily. +namesMatching :: String -> IO [FilePath] +namesMatching pat + | not (isPattern pat) = do + exists <- doesNameExist pat + return (if exists then [pat] else []) + | otherwise = do + case splitFileName pat of + ("", baseName) -> do + curDir <- getCurrentDirectory + listMatches curDir baseName + (dirName, baseName) -> do + dirs <- if isPattern dirName + then namesMatching (dropTrailingPathSeparator dirName) + else return [dirName] + let listDir = if isPattern baseName + then listMatches + else listPlain + pathNames <- forM dirs $ \dir -> do + baseNames <- listDir dir baseName + return (map (dir ) baseNames) + return (concat pathNames) + where isPattern = any (`elem` "[*?") + +listMatches :: FilePath -> String -> IO [String] +listMatches dirName pat = do + dirName' <- if null dirName + then getCurrentDirectory + else return dirName + names <- unsafeInterleaveIO (handle (\(_::IOException) -> return []) $ + getDirectoryContents dirName') + let names' = if isHidden pat + then filter isHidden names + else filter (not . isHidden) names + return (filter (~~ pat) names') + where isHidden ('.':_) = True + isHidden _ = False + +listPlain :: FilePath -> String -> IO [String] +listPlain dirName baseName = do + exists <- if null baseName + then doesDirectoryExist dirName + else doesNameExist (dirName baseName) + return (if exists then [baseName] else []) + +doesNameExist :: FilePath -> IO Bool +doesNameExist name = do + fileExists <- doesFileExist name + if fileExists + then return True + else doesDirectoryExist name diff --git a/System/FilePath/GlobPattern.hs b/System/FilePath/GlobPattern.hs new file mode 100644 --- /dev/null +++ b/System/FilePath/GlobPattern.hs @@ -0,0 +1,178 @@ +-- | +-- Module: System.FilePath.GlobPattern +-- Copyright: Bryan O'Sullivan +-- License: BSD3 +-- Maintainer: Bryan O'Sullivan +-- Stability: unstable +-- Portability: everywhere +module System.FilePath.GlobPattern ( + -- * Glob patterns + -- $syntax + GlobPattern + -- * Matching functions + , (~~) + , (/~) + ) where + +import Control.Arrow (second) +import Data.Ix (Ix, inRange) +import Data.List (nub) +import Data.Maybe (isJust) +import System.FilePath (pathSeparator) + +-- $syntax +-- +-- Basic glob pattern syntax is the same as for the Unix shell +-- environment. +-- +-- * @*@ matches everything up to a directory separator or end of +-- string. +-- +-- * @[/range/]@ matches any character in /range/. +-- +-- * @[!/range/]@ matches any character /not/ in /range/. +-- +-- There are three extensions to the traditional glob syntax, taken +-- from modern Unix shells. +-- +-- * @\\@ escapes a character that might otherwise have special +-- meaning. For a literal @\"\\\"@ character, use @\"\\\\\"@. +-- +-- * @**@ matches everything, including a directory separator. +-- +-- * @(/s1/|/s2/|/.../)@ matches any of the strings /s1/, /s2/, etc. + +-- | Glob pattern type. +type GlobPattern = String + +spanClass :: Char -> String -> (String, String) + +spanClass c = gs [] + where gs _ [] = error "unterminated character class" + gs acc (d:ds) | d == c = (reverse acc, ds) + | d == '\\' = case ds of + (e:es) -> gs (e:'\\':acc) es + _ -> error "unterminated escape" + | otherwise = gs (d:acc) ds + +data Ix a => SRange a = SRange [a] [(a, a)] + deriving (Show) + +inSRange :: Ix a => a -> SRange a -> Bool + +inSRange c (SRange d s) = c `elem` d || any (flip inRange c) s + +type CharClass = SRange Char + +makeClass :: String -> CharClass + +makeClass = makeClass' [] [] + where makeClass' :: [(Char, Char)] -> [Char] -> String -> CharClass + makeClass' dense sparse [] = SRange sparse dense + makeClass' dense sparse (a:'-':b:cs) = + makeClass' ((a,b):dense) sparse cs + makeClass' dense sparse (c:cs) = makeClass' dense (c:sparse) cs + +data MatchTerm = MatchLiteral String + | MatchAny + | MatchDir + | MatchChar + | MatchClass Bool CharClass + | MatchGroup [String] + deriving (Show) + +parseGlob :: GlobPattern -> [MatchTerm] + +parseGlob [] = [] +parseGlob ('*':'*':cs) = MatchAny : parseGlob cs +parseGlob ('*':cs) = MatchDir : parseGlob cs +parseGlob ('?':cs) = MatchChar : parseGlob cs +parseGlob ('[':cs) = let (cc, ccs) = spanClass ']' cs + cls = case cc of + ('!':ccs') -> MatchClass False $ makeClass ccs' + _ -> MatchClass True $ makeClass cc + in cls : parseGlob ccs +parseGlob ('(':cs) = let (gg, ggs) = spanClass ')' cs + in MatchGroup (breakGroup [] gg) : parseGlob ggs + where breakGroup :: String -> String -> [String] + breakGroup acc [] = [reverse acc] + breakGroup _ ['\\'] = error "group: unterminated escape" + breakGroup acc ('\\':c:cs') = breakGroup (c:acc) cs' + breakGroup acc ('|':cs') = reverse acc : breakGroup [] cs' + breakGroup acc (c:cs') = breakGroup (c:acc) cs' +parseGlob ['\\'] = error "glob: unterminated escape" +parseGlob ('\\':c:cs) = MatchLiteral [c] : parseGlob cs +parseGlob (c:cs) = MatchLiteral [c] : parseGlob cs + +simplifyTerms :: [MatchTerm] -> [MatchTerm] +simplifyTerms [] = [] +simplifyTerms (MatchLiteral []:as) = simplifyTerms as +simplifyTerms (m@(MatchLiteral a):as) = + case simplifyTerms as of + (MatchLiteral b:bs) -> MatchLiteral (a ++ b) : bs + bs -> m : bs +simplifyTerms (MatchClass True (SRange [] []):as) = simplifyTerms as +simplifyTerms (MatchClass True (SRange a@[_] []):as) = + simplifyTerms $ MatchLiteral a : as +simplifyTerms (MatchGroup []:as) = simplifyTerms as +simplifyTerms (MatchGroup gs:as) = + case commonPrefix gs of + (p,[]) -> simplifyTerms (MatchLiteral p : as) + (p,ss) -> simplifyTerms (MatchLiteral p : MatchGroup ss : as) +simplifyTerms (a:as) = a:simplifyTerms as + +commonPrefix :: [String] -> (String, [String]) +commonPrefix = second nub . pfx "" + where pfx _ [] = ("", []) + pfx acc ss | any null ss = (reverse acc, ss) + | otherwise = let hs = map head ss + h = head hs + in if all (h==) $ tail hs + then pfx (h:acc) $ map tail ss + else (reverse acc, ss) + +matchTerms :: [MatchTerm] -> String -> Maybe () + +matchTerms [] [] = return () +matchTerms [] _ = fail "residual string" +matchTerms (MatchLiteral m:ts) cs = matchLiteral m cs >>= matchTerms ts + where matchLiteral (a:as) (b:bs) | a == b = matchLiteral as bs + matchLiteral [] as = return as + matchLiteral _ _ = fail "not a prefix" +matchTerms (MatchClass k c:ts) cs = matchClass cs >>= matchTerms ts + where matchClass (b:bs) | (inClass && k) || not (inClass || k) = return bs + where inClass = b `inSRange` c + matchClass _ = fail "no match" +matchTerms (MatchGroup g:ts) cs = matchGroup g cs >>= matchTerms ts + where matchGroup g' as | any null g' = return as + matchGroup g' (a:as) | a `elem` map head g' = + matchGroup (map tail g') as + matchGroup _ _ = fail "not in group" +matchTerms [MatchAny] _ = return () +matchTerms (MatchAny:ts) cs = matchAny cs >>= matchTerms ts + where matchAny [] = fail "no match" + matchAny cs' = case matchTerms ts cs' of + Nothing -> matchAny (tail cs') + _ -> return cs +matchTerms [MatchDir] cs | pathSeparator `elem` cs = fail "path separator" + | otherwise = return () +matchTerms (MatchDir:ts) cs = matchDir cs >>= matchTerms ts + where matchDir [] = fail "no match" + matchDir (c:_) | c == pathSeparator = fail "path separator" + matchDir cs' = case matchTerms ts cs' of + Nothing -> matchDir $ tail cs' + _ -> return cs' +matchTerms (MatchChar:_) [] = fail "end of input" +matchTerms (MatchChar:ts) (_:cs) = matchTerms ts cs + +-- | Match a file name against a glob pattern. +(~~) :: FilePath -> GlobPattern -> Bool + +name ~~ pat = let terms = simplifyTerms (parseGlob pat) + in (isJust . matchTerms terms) name + +-- | Match a file name against a glob pattern, but return 'True' if +-- the match /fail/s. +(/~) :: FilePath -> GlobPattern -> Bool + +(/~) = (not . ) . (~~) diff --git a/System/FilePath/Manip.hs b/System/FilePath/Manip.hs new file mode 100644 --- /dev/null +++ b/System/FilePath/Manip.hs @@ -0,0 +1,113 @@ +{-# LANGUAGE FlexibleInstances, ScopedTypeVariables, TypeSynonymInstances #-} + +-- | +-- Module: System.FilePath.Manip +-- Copyright: Bryan O'Sullivan +-- License: BSD3 +-- Maintainer: Bryan O'Sullivan +-- Stability: unstable +-- Portability: Unix-like systems (requires flexible instances) + +module System.FilePath.Manip ( + Streamable(..) + , renameWith + , modifyWith + , modifyWithBackup + , modifyInPlace + ) where + +import Control.Exception +import Control.Monad (liftM) +import Data.Bits ((.&.)) +import System.Directory (removeFile) +import System.IO (Handle, IOMode(..), hClose, openFile) +import System.Posix.Files (fileMode, getFileStatus, rename, setFileMode) +import System.Posix.Temp (mkstemp) +import qualified Data.ByteString.Char8 as B +import qualified Data.ByteString.Lazy.Char8 as L +import qualified System.IO as I + +-- | Use a renaming function to generate a new name for a file, then +-- rename it. +renameWith :: (FilePath -> FilePath) -- ^ function to rename with + -> FilePath -- ^ file to rename + -> IO () + +renameWith f path = rename path (f path) + +-- | Type class for string manipulation over files. +class Streamable a where + -- | Read the entire contents of a 'Handle'. + readAll :: Handle -> IO a + -- | Write an entire string to a 'Handle'. + writeAll :: Handle -> a -> IO () + +instance Streamable B.ByteString where + readAll = B.hGetContents + writeAll = B.hPut + +instance Streamable L.ByteString where + readAll = L.hGetContents + writeAll = L.hPut + +instance Streamable String where + readAll = I.hGetContents + writeAll = I.hPutStr + +-- | Modify a file in place using the given function. This is +-- performed by writing to a temporary file, then renaming it on top of +-- the existing file when done. +modifyInPlace :: Streamable a => (a -> a) -- ^ transformation function + -> FilePath -- ^ name of file to modify + -> IO () + +modifyInPlace = modifyWith (flip rename) + +-- | Modify a file in place using the given function. The original +-- copy of the file is saved under a new name. This is performed by +-- writing to a temporary file; renaming the original file to its new +-- name; then renaming the temporary file to the original name. +-- +-- Example: +-- +-- @ +-- -- save original file with a \".bak\" extension +-- 'modifyWithBackup' (\<.\> \"bak\") +-- @ +modifyWithBackup :: Streamable a => + (FilePath -> FilePath) -- ^ chooses new name for original file + -> (a -> a) -- ^ transformation function + -> FilePath -- ^ name of file to modify + -> IO () + +modifyWithBackup f = modifyWith backup + where backup path tmpPath = renameWith f path >> rename tmpPath path + +-- | Modify a file in place using the given function. The new content +-- is written to a temporary file. Once this is complete, the file +-- manipulation action is called. Its arguments are the names of the +-- original and temporary files. +-- +-- Example: +-- +-- @ +-- 'modifyInPlace' = 'modifyWith' (flip rename) +-- @ +modifyWith :: Streamable a => + (FilePath -> FilePath -> IO ()) -- ^ file manipulation action + -> (a -> a) -- ^ transformation function + -> FilePath + -> IO () + +modifyWith after transform path = + bracket (openFile path ReadMode) hClose $ \ih -> do + (tmpPath, oh) <- mkstemp (path ++ "XXXXXX") + let ignore = return () + nukeTmp = handle (\(_::IOException) -> ignore) (removeFile tmpPath) + handle (\(e::IOException) -> nukeTmp >> throw e) $ do + bracket_ ignore (hClose oh) $ + readAll ih >>= return . transform >>= writeAll oh + handle (\(_::IOException) -> nukeTmp) $ do + mode <- fileMode `liftM` getFileStatus path + setFileMode tmpPath (mode .&. 0777) + after path tmpPath diff --git a/filemanip.cabal b/filemanip.cabal new file mode 100644 --- /dev/null +++ b/filemanip.cabal @@ -0,0 +1,30 @@ +Name: filemanip +Version: 0.3.5.0 +License: BSD3 +License-File: LICENSE +Author: Bryan O'Sullivan +Maintainer: Bryan O'Sullivan +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. +Cabal-version: >= 1.6 +Build-type: Simple + +Extra-Source-Files: README.markdown + +Library + build-depends: base < 5, bytestring, directory, filepath, mtl, unix-compat + if !os(windows) + build-depends: unix + if impl(ghc >= 6.10) + build-depends: + base >= 4 + + GHC-Options: -Wall + Exposed-Modules: + System.FilePath.Find, + System.FilePath.Glob, + System.FilePath.GlobPattern, + System.FilePath.Manip