canonical-filepath (empty) → 1.0

raw patch · 4 files changed

+194/−0 lines, 4 filesdep +basedep +deepseqdep +directorysetup-changed

Dependencies added: base, deepseq, directory, filepath

Files

• LICENSE +29/−0
• Setup.hs +4/−0
• System/FilePath/Canonical.hs +138/−0
• canonical-filepath.cabal +23/−0

@@ -0,0 +1,29 @@+Copyright 2011, Thomas Schilling+All rights reserved.++Redistribution and use in source and binary forms, with or without+modification, are permitted provided that the following conditions are met:++- Redistributions of source code must retain the above copyright notice,+this list of conditions and the following disclaimer.+ +- 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.+ +- Neither name of the author nor the names of its contributors may be+used to endorse or promote products derived from this software without+specific prior written permission. ++THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) AND THE 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 UNIVERSITY+COURT OF THE UNIVERSITY OF GLASGOW OR THE 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.

@@ -0,0 +1,4 @@+#!/usr/bin/env runhaskell+import Distribution.Simple+main :: IO ()+main = defaultMain

@@ -0,0 +1,138 @@+-- |+-- Module      :  System.FilePath+-- Copyright   :  (c) Thomas Schilling 2011+-- License     :  BSD-style+-- +-- Maintainer  :  nominolo@googlemail.com+-- Stability   :  stable+-- Portability :  portable+--+-- Abstract data type for canonical file paths.+--+-- Due to the context sensitive way in which file paths are specified+-- on today's computer systems it is useful to have the notion of a+-- /canonical/ 'FilePath'.+--+-- The basic feature is that two canonical file paths @cfp1@ and+-- @cfp2@ refer to the same file if and only if @cfp1 == cfp2@.+-- This property can be achieved using 'canonicalizePath'.+-- However, if given an arbitrary @FilePath@ we don't know whether+-- it is canonical so having a separate type is useful.  Secondly,+-- @canonicalizePath@ might fail if the target path does not exist+-- on the system.+-- +-- This module therefore provides an abstract type that represents+-- paths that have been canonicalised.  The intended use+-- straightforward, just use 'canonical' to create a+-- 'CanonicalFilePath'.+--+-- @example = do +--  cfp1 \<- 'canonical' \"./foo\"+--  curr \<- getCurrentDirectory+--  cfp2 \<- canonical (curr \</> \"foo\")+--  print (cfp1 == cfp2)  \-- should print \"True\"+-- @+--+-- To extract a canonical @FilePath@ use 'canonicalFilePath' (don't+-- use 'show').+module System.FilePath.Canonical+  ( -- * Abstract Type+    CanonicalFilePath,+    -- * Creation+    canonical,+    -- * Deconstruction +    originalFilePath, canonicalFilePath,+    -- * Unsafe\/Internal Operations+    unsafeCanonicalise+  )+where++import Control.DeepSeq+import Control.Monad ( liftM2 )+import System.FilePath ( equalFilePath, (</>) )+import System.Directory ( canonicalizePath, getCurrentDirectory,+                          doesFileExist, doesDirectoryExist )+{-+import Data.Binary+import Data.Binary.Get+import Data.Binary.Put+import qualified Codec.Binary.UTF8.String as UTF8+-}++-- | A canonical 'FilePath'.+--+-- Construct values of this type using the 'canonical' function.+--+-- Note that it is not always possible to guarantee a truly canonical+-- path due to various file system features.  For more information see+-- the documentation of @realpath@ in your favourite man page.+--+data CanonicalFilePath =+  UnsafeCanonicalise {+    -- | The original input to 'canonical'.+    originalFilePath :: FilePath,+    -- | The canonical path.+    canonicalFilePath :: FilePath }++instance Show CanonicalFilePath where+  show = originalFilePath++instance Eq CanonicalFilePath where+  cfp1 == cfp2 =+    canonicalFilePath cfp1 `equalFilePath` canonicalFilePath cfp2++instance Ord CanonicalFilePath where+  cfp1 `compare` cfp2 =+    canonicalFilePath cfp1 `compare` canonicalFilePath cfp2++instance NFData CanonicalFilePath where+  rnf (UnsafeCanonicalise a b) = rnf a `seq` rnf b++{-+instance Binary CanonicalFilePath where+  get = liftM2 UnsafeCanonicalise getUTF8String getUTF8String+   where+     getUTF8String = do+       n <- getWord32le+       fmap UTF8.decode $ sequence (replicate (fromIntegral n) getWord8)++  put (UnsafeCanonicalise fp1 fp2) = putUTF8String fp1 >> putUTF8String fp2+   where+     putUTF8String s_ = do+       let s = UTF8.encode s_+       putWord32le (fromIntegral (length s))+       mapM_ putWord8 s+-}++-- | Construct a canonical file path from the given path.+--+-- Unlike 'canonicalizePath' this operation works even if the file or+-- its containing directory does not exist, but it may fail due to+-- other reasons (e.g., permission errors).+--+canonical :: FilePath -> IO CanonicalFilePath+canonical fp = do+  exists <- liftM2 (||) (doesFileExist fp) (doesDirectoryExist fp)+  if exists+    then fmap (UnsafeCanonicalise fp) $ canonicalizePath fp+    else fmap (UnsafeCanonicalise fp . (</> fp)) getCurrentDirectory++-- | Unsafely constructs a 'CanonicalFilePath'.+--+-- It is unsafe in the sense that it is up to the caller to guarantee+-- that the second argument is indeed a canonical file path.+--+-- This function is intended mainly to aid in writing custom+-- serialisation instances.+unsafeCanonicalise :: FilePath -- ^ Original file path+                   -> FilePath -- ^ Canonical file path.+                   -> CanonicalFilePath+unsafeCanonicalise = UnsafeCanonicalise++{- from the docs+test = do+  cfp1 <- canonical "./foo"+  curr <- getCurrentDirectory+  cfp2 <- canonical (curr </> "foo")+  print (cfp1 == cfp2)  -- should print "True"+-}

@@ -0,0 +1,23 @@+name:                   canonical-filepath+version:                1.0+license:                BSD3+license-file:           LICENSE+author:                 Thomas Schilling <nominolo@googlemail.com>+maintainer:             Thomas Schilling <nominolo@googlemail.com>+homepage:               http://github.com/nominolo/canonical-filepath+synopsis:               Abstract data type for canonical file paths.+description:+  Abstract data type for canonical file paths.+category:               System+stability:              provisional+build-type:             Simple+cabal-version:          >= 1.6++library+  build-depends:+    base                >= 4     && < 5,+    deepseq             == 1.1.*,+    directory           == 1.1.*,+    filepath            == 1.2.*+  exposed-modules:+    System.FilePath.Canonical