backstop (empty) → 1.3.0.352
raw patch · 11 files changed
+3876/−0 lines, 11 filesdep +HUnitdep +QuickCheckdep +base
Dependencies added: HUnit, QuickCheck, base, directory, filepath, mtl, process, unix
Files
- CHANGELOG.md +13/−0
- LICENSE +674/−0
- README.md +292/−0
- backstop.cabal +78/−0
- src/Backstop.hs +407/−0
- src/Environment.hs +48/−0
- src/License.hs +691/−0
- src/Main.hs +494/−0
- src/Manual.hs +272/−0
- src/Utils.hs +266/−0
- tests/RunTests.hs +641/−0
+ CHANGELOG.md view
@@ -0,0 +1,13 @@+# Revision history for backstop++## 1.3.0.350 -- 2019-07-11++* First version. Released on an unsuspecting world.++## 1.3.0.351 -- 2019-07-14++* First cabal package.++## 1.3.0.352 -- 2019-07-14++* Small documentation corrections.
+ LICENSE view
@@ -0,0 +1,674 @@+ GNU GENERAL PUBLIC LICENSE+ Version 3, 29 June 2007++ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>+ Everyone is permitted to copy and distribute verbatim copies+ of this license document, but changing it is not allowed.++ Preamble++ The GNU General Public License is a free, copyleft license for+software and other kinds of works.++ The licenses for most software and other practical works are designed+to take away your freedom to share and change the works. By contrast,+the GNU General Public License is intended to guarantee your freedom to+share and change all versions of a program--to make sure it remains free+software for all its users. We, the Free Software Foundation, use the+GNU General Public License for most of our software; it applies also to+any other work released this way by its authors. You can apply it to+your programs, too.++ When we speak of free software, we are referring to freedom, not+price. 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+ README.md view
@@ -0,0 +1,292 @@+# The backstop command++The backstop command is a UNIX, Linux, and *BSD tool. Intuitively,+backstop fills in the missing objects or holes that exist in the+target directory relative to the source directories thereby creating a+merged view of the target and source directories. De-backstop undoes+this. See "backstop -m" for a manual page or the+[homepage](https://github.com/mdgabriel/backstop.git) for more+information.++The command backstop was created over twenty years ago to manage+development environement toolchains in which part of the project was+under source control and part of the project was not, e.g. binaries.+It was inspired by lndir, graft, and "Source Control to Project+Control: Applying RCS and SCCS" by Don Bolinger and Tan Bronson.+Techniques have changed with time, but backstop is a robust tool+with an extensive test suite that runs around 2700 tests, a+combination of HUnit, QuickCheck, and black box tests.++In the author's obviously biased veiw, backstop has pedagogical+value. The module Backstop uses a ReaderT monad transformer to+manage an Environment passed to it via the command line, a StateT+monad transformer to keep track of a set of counters and to keep track+of the status of direcotry content while backstopping or+de-backstopping. The last two are Monoids. With this structure,+the handling of a dry-run for backstop or de-backstop is rather+powerful even it is a bit subtle (obscure) to understand.++On a personal note, the author truly began to appreciate Haskell after+creating the Backstop module and its test suite and has not stopped+appreciating Haskell since.++# The backstop manual page++```backstop(1) User Commands backstop(1)++NAME+ backstop - Backstop a target directory by source directories++SYNOPSIS+ backstop [-nprt] [-a|-d] trgdir srcdir [srcdir ...]+ backstop -h+ backstop -l+ backstop -m+ backstop -v+ backstop -y++AVAILABILITY+ Marcus D. Gabriel (c)1999-2019. All rights reserved.++ marcus@gabriel.name++ License terms: GNU GPL version 3 or later (backstop -l)++DESCRIPTION+ Backstop a target directory by source directories thereby+ creating a backing chain using relative symbolic links by default+ or absolute symbolic links by option. If more than one source+ directory is given, backstop the target directory with each+ source directory in turn starting from left to right on the+ command line.++ Intuitively, backstop fills in the missing objects or holes that+ exist in the target directory relative to the source directories+ thereby creating a merged view of the target and source+ directories.++ De-backstop a target directory by its source directories. In+ this case, the source directories no longer need to exist. If+ more than one source directory is given, de-backstop the target+ directory by the source directories.++ Symbolic links are never followed. However, the target and+ source directories are canonicalized (realpath(3)) internally by+ the command backstop before backstopping and de-backstoppoing.++ By default no output is displayed except possibly to STDERR.++ALGORITHM+ There must be at least two arguments or operands. The first+ operand is the target directory, and the second operand and+ beyond are source directories. The target and source directory+ must be parallel directories, that is, neither canonicalized+ (realpath(3)) directory path may be a sub-directory of the other.+ If the above is not true, a usage error occurs.++ Nevertheless, pathnames are internally in reduced form such that+ symbolic link names are treated literally when finding directory+ names. See "cd -L" of ksh(1). In other words, components in the+ pathname that are not directories but symbolic links to+ directories are not resolved to their corresponding directories.++ A list of objects or names is collected under the root of the+ source directory excluding the directory dot (.) and the+ directory double-dot (..). If the list is empty, the algorithm+ is done, otherwise the objects divide into two classes, objects+ that are not directories and objects that are directories. There+ are five possibilities:++ 1. The object is either dot (.) or double-dot (..) whereupon no+ action is taken.++ 2. If an object of the same name as the name of the object under+ the root of the source directory does not exists under the+ root of the target directory, then a symbolic link, relative+ or absolute as required, is created under the root of the+ target directory to the object under the root of the source+ directory. If populating (-p) and the object under the root+ of the source directory is a directory, then a sub-directory+ is created instead.++ 3. If an object of the same name as the name of the object under+ the root of the source directory does exists under the root of+ the target directory and is a file, no action is taken,+ regardless of whether or not the object under the root of the+ source directory is a file or a directory.++ 4. If an object of the same name as the name of the object under+ the root of the source directory does exists under the root of+ the target directory and is a directory, and if the object of+ the same name under the root of the source directory is a+ file, no action is taken.++ 5. If an object of the same name as the name of the object under+ the root of the source directory does exists under the root of+ the target directory and is a directory, and if the object of+ the same name under the root of the source directory is also a+ directory, then recursion occurs with the objects of the same+ name under the roots of the target and source directories as+ new root target and source directories, respectively.++ When de-backstopping a target directory by source directories,+ the sources no longer need to exist. Symbolic links under the+ target are removed if and only if they point to a pahtname under+ one of the source directories. This can be determined even if+ the source directory no longer exists because symbolic links+ within directory pathnames are taken literally. See "cd -L" of+ ksh(1).++ When de-populating while de-backstopping (-pd), a directory is+ removed if all objects within the directory are symbolic links+ that have been remove while de-backstopping. An empty directory+ is removed if and only if there exists a corresponding directory+ path under one of the source directories as under the target+ directory. This can only be determined if the source directory+ and correponding sub-directory still exist. If not, then no+ action is taken.++OPTIONS+ The following options are supported:++ -a Create symbolic links which are absolute paths.++ -d De-backstop the target directory by its source directories.+ The -a option has no affect on the -d option.++ -h Display a short command summary.++ -l Display the backstop license terms.++ -m Display this internal manual page.++ -n Take no action but trace possible program execution. The -n+ option implies the -t option.++ -p Populate the target by making equivalent sub-directories of+ the source sub-directories instead of symbolic links for these+ sub-directories that point back into the sources. For+ example, if the target directory is empty, then for a set of+ source directories, from left to right on the command line,+ this creates a combined directory structure of the sources+ under the target directory in which all non-directories are+ symbolic links pointing back into the source directories.+ This is similar to the lndir(1) command of the X consortium.++ With the -d option, all sub-directories emptied of symbolic+ links under the target directory are removed, and all empty+ directories are removed if and only if the correspoding+ sub-directory under the source directory exists.++ -r Report the number of symbolic links and directories created,+ the number of calls and maximum depth of backstop, the+ maximum breadth observed by backstop, and the number of non-+ fatal errors encountered. With the -d option, show the+ number of symbolic links and directories removed.++ -t Show the trace of program execution. The output is a list+ of executable commands.++ -v The version of backstop.++ -y A synopsis of the internal manual page.++OPERANDS+ trgdir+ The directory that will be backed by other directories. The+ target directory can be backed by multiple source directories+ where each source directory could be backed by yet another+ directory or multiple directories thereby creating an+ extensible backing chain.++ srcdir+ The directory which backs a target directory. The source+ directory can be backed by multiple additional directories+ where each additional directory could be backed by yet another+ directory or multiple directories thereby creating an+ extensible backing chain.++USAGE NOTES+ Evolved with ghc 6.10, 6.12, 7.0, 7.4, 7.10, 8.0.2, and 8.4.1.+ Tested with 8.4.1.++EXAMPLES+ To display a summary of usage, use++ backstop -h++ To display a synopsis of this internal manual page, use++ backstop -y++ To display this internal manual page, use++ backstop -m++ To trace program execution, use++ backstop -t /export/install/sparc/devlopment/modules \+ /export/install/sparc/modules++ To trace program execution taking no action, use++ backstop -n /export/install/sparc/devlopment/modules \+ /export/install/sparc/modules++ To back /export/install/sparc/devlopment/modules with+ /export/install/sparc/modules using relative symbolic links, use++ backstop /export/install/sparc/devlopment/modules \+ /export/install/sparc/modules++ To back /export/install/sparc/devlopment/modules with+ /export/install/sparc/modules using absolute symbolic links, use++ backstop -a /export/install/sparc/devlopment/modules \+ /export/install/sparc/modules++ To stop backing /export/install/sparc/devlopment/modules with+ /export/install/sparc/modules, use++ backstop -d /export/install/sparc/devlopment/modules \+ /export/install/sparc/modules++ENVIRONMENT VARIABLES+ PAGER Page the internal manual page or license terms+ using "${PAGER}", otherwise print it.++EXIT STATUS+ An exit status of 0 is returned if successful, otherwise non-zero+ is returned. The following error exit codes are used by+ backstop:++ EXIT CODE MEANING+ 251 Less than two operands.+ 252 Not a directory, that is, trgdir or one or more+ of the srcdir are not a directory.+ 253 Not parallel directories, that is, a srcdir is+ a sub-directory of trgdir or vice versa, or one+ of the srcdir is a sub-directory of another+ srcdir.+ 254 Not yet implemented.+ 255 Non-fatal errors occurred. Error messages are+ sent to STDERR for each non-fatal error that+ occurred with return code equal to the number of+ non-falal errors if less than 251, otherwise the+ return code is 255, that is, "infinity".++FILES+ N/A.++SEE ALSO+ ln(1), mkdir(1), rm(1), rmdir(1), ksh(1), lndir(1), realpath(3)++ "Source Control to Project Control: Applying RCS and SCCS" by Don+ Bolinger and Tan Bronson. ISBN 1-56592-117-8.++NOTES+ Please send bug reports to https://github.com/mdgabriel/backstop/issues.++BUGS+ No known bugs to date.+```
+ backstop.cabal view
@@ -0,0 +1,78 @@+cabal-version: 2.4+name: backstop+version: 1.3.0.352+license: GPL-3.0-only+license-file: LICENSE+copyright: All rights reserved (c)1999-2019.+maintainer: marcus@gabriel.name+author: Marcus D. Gabriel+homepage: https://github.com/mdgabriel/backstop.git+bug-reports: https://github.com/mdgabriel/backstop/issues+synopsis: Backstop a target directory by source directories+description:+ The backstop command is a UNIX, Linux, and *BSD tool. Intuitively,+ backstop fills in the missing objects or holes that exist in the+ target directory relative to the source directories thereby+ creating a merged view of the target and source directories.+ De-backstop undoes this. See "backstop -m" for a manual page+ or the [homepage](https://github.com/mdgabriel/backstop.git)+ for more information.+category: program, development, library+extra-source-files:+ CHANGELOG.md+ README.md++source-repository head+ type: git+ location: https://github.com/mdgabriel/backstop.git+ tag: 1.3.0.351++library+ exposed-modules:+ Backstop+ Environment+ License+ Manual+ Utils+ hs-source-dirs: src+ default-language: Haskell2010+ build-depends:+ base >=4.12.0.0 && <4.13,+ directory >=1.3.3.0 && <1.4,+ filepath >=1.4.2.1 && <1.5,+ mtl >=2.2.2 && <2.3,+ process >=1.6.5.0 && <1.7,+ unix >=2.7.2.2 && <2.8++executable backstop+ main-is: Main.hs+ hs-source-dirs: src+ other-modules:+ Backstop+ Environment+ License+ Manual+ Utils+ default-language: Haskell2010+ build-depends:+ base >=4.12.0.0 && <4.13,+ directory >=1.3.3.0 && <1.4,+ filepath >=1.4.2.1 && <1.5,+ mtl >=2.2.2 && <2.3,+ process >=1.6.5.0 && <1.7,+ unix >=2.7.2.2 && <2.8++test-suite run-tests+ type: exitcode-stdio-1.0+ main-is: RunTests.hs+ hs-source-dirs: src tests+ other-modules:+ Utils+ default-language: Haskell2010+ build-depends:+ base ==4.*,+ HUnit >=1.6.0.0 && <1.7,+ QuickCheck >=2.13.2 && <2.14,+ filepath >=1.4.2.1 && <1.5,+ process >=1.6.5.0 && <1.7,+ unix >=2.7.2.2 && <2.8
+ src/Backstop.hs view
@@ -0,0 +1,407 @@+{-# LANGUAGE FlexibleContexts #-}+module Backstop (backstop) where++import Control.Applicative ((<$>))+import Control.Exception (try)+import Control.Monad.Reader (ask,ReaderT,runReaderT,withReaderT)+import Control.Monad.State.Strict (put,lift,when,evalStateT,get,StateT,runStateT,filterM)+import Control.Monad.Trans (liftIO)+import Data.List ((\\),sort,delete)+import Data.Monoid --(Monoid(..))+import Environment (Environment(..),defaultEnv)+import System.Exit (exitWith,ExitCode(..))+import System.FilePath ((</>),isAbsolute)+import System.Directory (createDirectory,removeDirectory,removeFile,getDirectoryContents)+import System.IO (stderr,hPutStrLn)+import System.IO.Error hiding (try)+import System.Posix.Files (readSymbolicLink,isDirectory,isSymbolicLink,createSymbolicLink,getSymbolicLinkStatus)+import Utils (aDirectory,compElems,absoluteLink,relativeLink,subdirectory,dot,dotdot,anObject)+++-- Section 0: The interface to Main.runWith: Backstop.backstop ----------------------++-- | 'backstop' the 'Environment' reporting a summary if requested,+-- any errors, and a return code. The return code is either 0 for+-- success, the number of errors, or 255 for infinity.++backstop :: Environment -> IO ()+backstop e =+ do bs <- runReaderT (if deBackstop e then _unbackstop else _backstop) e+ when (report e) $ putBackstop bs+ exitWith $ if errs bs > 0+ then ExitFailure (if errs bs < 251 then errs bs else 255)+ else ExitSuccess+++-- Section 1 ------------------------------------------------------------------------++data Backstop =+ BS { calls :: Int -- ^ Number of calls to 'backstop'+ , depth :: Int -- ^ Depth of recursion of 'backstop'+ , breadth :: Int -- ^ Breadth for the given call to and depth of 'backstop'+ , symlinks :: Int -- ^ Number of symlinks created or removed+ , dirs :: Int -- ^ Number of directories created or removed+ , errs :: Int -- ^ Number of non-fatal IO errors that occurred+ } deriving Eq++instance Semigroup Backstop where+ bs1 <> bs2 = let add f = f bs1 + f bs2+ biggest f = max (f bs1) (f bs2)+ in BS (add calls)+ (add depth)+ (biggest breadth)+ (add symlinks)+ (add dirs)+ (add errs)++instance Monoid Backstop where+-- Because of the use of biggest below, this instance of mempty is+-- only an identity of a monoid for all Int >= 0. This is the case in+-- the Backstop module. The monoid laws do not hold for Int < 0.+ mempty = BS 0 0 0 0 0 0++-- | Put to STDERR the 'Backstop' results 'symlinks', 'dirs', 'calls',+-- 'depth', 'breadth', and 'errs'.++putBackstop :: Backstop -> IO ()+putBackstop bs =+ hPutStrLn stderr ("Symlinks: " ++ (justify 5.show.symlinks) bs ++ "; " +++ "Dirs: " ++ (justify 4.show.dirs) bs ++ "; " +++ "Calls: " ++ (justify 4.show.calls) bs ++ "; " +++ "Depth: " ++ (justify 4.show.depth) bs ++ "; " +++ "Breadth: " ++ (justify 3.show.breadth) bs ++ "; " +++ "Errs: " ++ (justify 3.show.errs) bs+ )+ where+ justify w s = let l = length s in (if l < w then (replicate (w-l) ' ' ++) else id) s+++-- Section 2 ------------------------------------------------------------------------++-- | '_backstop' the 'Environment' keeping track of the 'Backstop' results.++_backstop :: ReaderT Environment IO Backstop+_backstop =+ do e <- ask+ if (length.operands) e < 2+ then return oneCall+ else do bs1 <- __backstop+ bs2 <- withReaderT nextSource _backstop+ return (bs1 `mappend` bs2)+ where+ __backstop =+ do e <- ask+ let t = operands e !! 0+ let s = operands e !! 1+ (bs1, ts) <- listDirectoryContents t+ (bs2, ss) <- listDirectoryContents s+ let (ps12, _, ps2) = compElems ts ss+ bs3 <- createObjects ps2+ ds <- listDirectories (ps12++ps2)+ bs4 <- mconcat <$> mapM (\d -> withReaderT (nextDepth d) __backstop) ds+ (return.mconcat) [bs4, bs3, bs2, bs1, oneCall, if null ds then mempty else oneDepth]++-- | Given an 'Environment' and a list of pathnames @ps@, create the+-- objects which are links from the target to the source or+-- directories as required yielding the 'Backstop' result.++createObjects :: [FilePath] -> ReaderT Environment IO Backstop+createObjects = fmap mconcat . mapM createObject++-- | 'createObject' attempts to create a symbolic link or directory+-- given an 'Environment' and a basename pathname @p@ yielding+-- the 'Backstop' result.++createObject :: FilePath -> ReaderT Environment IO Backstop+createObject p =+ do e <- ask+ if (length.operands) e < 2 then return mempty else _createObject p+ where+ prt p t s = liftIO $ putStr $ if p+ then "mkdir " ++ "\"" ++ t ++ "\"\n"+ else "ln -s " ++ "\"" ++ s ++ "\" " ++ "\"" ++ t ++ "\"\n"+ _createObject p =+ do e <- ask+ let d = pwd e+ let t = (operands e !! 0) </> p+ let s = (operands e !! 1) </> p+ let s_ = (if absolute e then absoluteLink else relativeLink) d t s+ p <- liftIO $ fmap (populate e &&) (aDirectory s)+ let one = if p then oneDir else oneSymlink+ when (trace e) $ prt p t s_+ if noAction e+ then return one+ else do (bs, _) <- tryOperation $ if p+ then createDirectory t+ else createSymbolicLink s_ t+ return $ if bs /= mempty then bs else one+++-- Section 3 ------------------------------------------------------------------------++data DirectoryContentStatus = Occupied -- ^ Directory occupied with remaining content after '__unbackstop'+ | Emptied -- ^ Directory was emptied by '__unbackstop'+ | Empty -- ^ Directory was empty when viewed by '__unbackstop'+ deriving Eq++instance Semigroup DirectoryContentStatus where+ dcs1 <> dcs2 = case (dcs1, dcs2) of+ (Occupied, _) -> Occupied+ (_, Occupied) -> Occupied+ (Empty, _) -> Empty+ (_, Empty) -> Empty+ (_,_) -> Emptied++instance Monoid DirectoryContentStatus where+ mempty = Emptied++type DCS = DirectoryContentStatus -- Short version++-- | '_unbackstop' the 'Environment' keeping track of the 'Backstop' results.++_unbackstop :: ReaderT Environment IO Backstop+_unbackstop =+ do e <- ask+ if (length.operands) e < 2+ then return oneCall+ else do -- Emptied when "empty" directory, otherwise Empty or set Occupied+ bs1 <- evalStateT __unbackstop Emptied+ bs2 <- withReaderT nextSource _unbackstop+ return (bs1 `mappend` bs2)+ where+ __unbackstop :: StateT DCS (ReaderT Environment IO) Backstop+ __unbackstop =+ do e <- ask+ let t = operands e !! 0+ (bs1, ts) <- lift $ listDirectoryContents t+ ds <- lift $ listDirectories ts+ let os = ts \\ ds+ bs2 <- destroyObjects os+ if null ds+ then do put $ if symlinks bs2 /= length os then Occupied+ else if null os then Empty else Emptied+ (return.mconcat) [bs2, bs1, oneCall]+ else do bs3 <- mconcat <$> mapM recurse ds+ dcs <- get+ put $ dcs `mappend` if symlinks bs2 /= length os then Occupied+ else if null os then Empty else Emptied+ (return.mconcat) [bs3, bs2, bs1, oneCall, oneDepth]++ recurse :: FilePath -> StateT DCS (ReaderT Environment IO) Backstop+ recurse d = do s1 <- get+ -- Emptied when "empty" directory, otherwise Empty or set Occupied+ (bs1, s2) <- lift $ withReaderT (nextDepth d) (runStateT __unbackstop Emptied)+ put s2+ bs2 <- destroyObjects [d]+ s3 <- get+ put (mconcat [s1, s2, s3])+ (return.mconcat) [bs2, bs1]++ {- Assume StateT monads for ms, then+ + sequence ms = foldr k (return []) ms+ where+ k mx mxs =+ StateT $ \s ->+ (runState mx) s >>= \ (x, s') ->+ (runStateT mxs) s' >>= \ (xs, s'') -> (x:xs, s'')++ Since mapM f xs is sequence (map f xs), it is recurse plus (dcs+ <- get) in __unbackstop above via mapM (sequence) that threads+ the DCS state value through __unbackstop. All put and get+ calls are in encapsulated in __unbackstop and all that it calls+ and only calls: destroyObjects, destroyObject, destroySymlink,+ and destroyDir. For now, only destroyDir has a get and a put.+ -}++-- | Given an 'Environment' and a list of pathnames @ps@, destroy the+-- objects which are links from the target to the source or+-- directories as required yielding the 'Backstop' result.++destroyObjects :: [FilePath] -> StateT DCS (ReaderT Environment IO) Backstop+destroyObjects = fmap mconcat . mapM destroyObject++-- | 'destroyObject' attempts to destroy a symbolic link or directory+-- given an 'Environment' and a basename pathname @p@ yielding+-- the 'Backstop' result.++destroyObject :: FilePath -> StateT DCS (ReaderT Environment IO) Backstop+destroyObject p =+ do e <- ask+ if (length.operands) e < 2 then return mempty else _destroyObject p+ where+ _destroyObject p =+ do e <- ask+ let trg = (operands e !! 0) </> p+ (bs, fs) <- lift $ tryOperation (getSymbolicLinkStatus trg)+ if bs /= mempty+ then return bs+ else if isSymbolicLink fs+ then destroySymlink p+ else if isDirectory fs+ then destroyDir p+ else return mempty++-- | 'destroySymlink' attempts to destroy a symbolic link given an+-- 'Environment' and a basename pathname @p@ yielding the 'Backstop'+-- result.++destroySymlink :: FilePath -> StateT DCS (ReaderT Environment IO) Backstop+destroySymlink p =+ do e <- ask+ if (length.operands) e < 2 then return mempty else _destroySymlink p+ where+ prt sym = liftIO $ putStr ("rm -f " ++ "\"" ++ sym ++ "\"\n")+ abs d p f = (if isAbsolute f then id else (d</>).(p</>)) f+ rm e sym = do when (trace e) $ prt sym+ if noAction e+ then return oneSymlink+ else do (bs, _) <- lift $ tryOperation (removeFile sym)+ return $ if bs /= mempty then bs else oneSymlink+ _destroySymlink p =+ do e <- ask+ let cwd = pwd e+ let trg = operands e !! 0+ let src = operands e !! 1+ let sym = trg </> p+ (bs, p) <- lift $ tryOperation (readSymbolicLink sym)+ if bs /= mempty+ then return bs+ else if not $ abs cwd trg p `subdirectory` abs cwd "" src+ then return mempty+ else rm e sym++-- | Given an 'Environment', remove an empty target directory @d@ if+-- and only if the corresonding directory path exists under the source+-- directory in which case the target directory is considered to have+-- been populated by the source directory yielding the 'Backstop'+-- result.++destroyDir :: FilePath -> StateT DCS (ReaderT Environment IO) Backstop+destroyDir p =+ do e <- ask+ if (length.operands) e < 2 || (not.populate) e then return mempty else _destroyDir p+ where+ prt dir = liftIO $ putStr ("rmdir \"" ++ dir ++"\"\n")+ _destroyDir p =+ do e <- ask+ let trg = (operands e !! 0) </> p+ let src = (operands e !! 1) </> p+ sDir <- liftIO $ aDirectory src+ dcs <- get+ if ((dcs == Empty) && not sDir) || (dcs == Occupied)+ then return mempty+ else do when (trace e) $ prt trg+ if noAction e+ then return oneDir+ else do (bs, _) <- lift $ tryOperation (removeDirectory trg)+ if bs /= mempty+ then do { put Occupied; return bs }+ else do { put Emptied; return oneDir }+++-- Section 4 ------------------------------------------------------------------------++-- | Given an 'Environment' and a pathname @p@,+-- 'listDirectoryContents' yields the sorted list @ps@ of directory+-- contents without the dot @(\".\")@ or double @(\"..\")@ directories+-- yielding the 'Backstop' result @bs@ in @(bs, ps)@.++listDirectoryContents :: FilePath -> ReaderT Environment IO (Backstop, [FilePath])+listDirectoryContents p =+ do directory <- liftIO $ aDirectory p+ if directory+ then do (bs, ps) <- tryOperation (sort . delete dotdot . delete dot <$> getDirectoryContents p)+ return $ if bs /= mempty then (bs, []) else (mempty{breadth = length ps}, ps)+ else return (mempty, [])++-- | 'listDirectories' of @ps@ for further backstopping by '_backstop'.++listDirectories :: [FilePath] -> ReaderT Environment IO [FilePath]+listDirectories ps =+ let dir e p =+ let t = (operands e !! 0) </> p+ s = (operands e !! 1) </> p+ in do tDir <- aDirectory t+ sDir <- aDirectory s+ tObj <- anObject t+ return $ if deBackstop e then tDir+ else if noAction e && populate e && not tObj+ then sDir else tDir && sDir+ in do e <- ask+ if (length.operands) e < 2 then return [] else liftIO $ filterM (dir e) ps+++-- Section 5 ------------------------------------------------------------------------++-- | Given an 'Environment', 'IO.try' the operation @IO a@ yielding+-- @(Backstop, a)@.++tryOperation :: IO a -> ReaderT Environment IO (Backstop, a)+tryOperation io =+ liftIO (try io) >>=+ either (\ioe -> putIOE ioe >> return (oneErr, error "N/A")) (\x -> return (mempty, x))++-- | Given an 'Environment', 'putIOE' prints an error message for+-- @ioe@ to STDERR.++putIOE :: IOError -> ReaderT Environment IO ()+putIOE ioe =+ do e <- ask+ let ln = ioeGetLocation ioe+ let fn = ioeGetFileName ioe+ let es = ioeGetErrorString ioe+ let s = command e ++ ": " ++ ln ++ ": " ++ maybe es (++": "++es) fn+ liftIO $ hPutStrLn stderr s+++-- Section 6 ------------------------------------------------------------------------++-- | Return the new 'Environment' given a pathname @p@ or the original+-- 'Environment' if done.++nextDepth :: FilePath -> Environment -> Environment+nextDepth p e =+ if (length.operands) e < 2+ then e+ else let t = operands e !! 0+ s = operands e !! 1+ in e{operands=[t </> p, s </> p]}+++-- | Return the next 'Environment' to process or the original+-- 'Environment' if done.++nextSource :: Environment -> Environment+nextSource e =+ if (length.operands) e < 2+ then e+ else e{operands=(head.operands) e : (tail.tail.operands) e}+++-- Section 7 ------------------------------------------------------------------------++-- | Set 'calls' to one in 'mempty'.++oneCall :: Backstop+oneCall = mempty{calls = 1}++-- | Set 'depth' to one in 'mempty'.++oneDepth :: Backstop+oneDepth = mempty{depth = 1}++-- | Set 'symlinks' to one in 'mempty'.++oneSymlink :: Backstop+oneSymlink = mempty{symlinks = 1}++-- | Set 'dirs' to one in 'mempty'.++oneDir :: Backstop+oneDir = mempty{dirs = 1}++-- | Set 'errs' to one in 'mempty'.++oneErr :: Backstop+oneErr = mempty{errs = 1}
+ src/Environment.hs view
@@ -0,0 +1,48 @@+module Environment (Environment(..),defaultEnv) where++-- Section: environment (to be configured)+{- |+The environment contains the command name, operands, and the result of+every option at least. It may contain other items that need to be+updated.+-}+data Environment =+ Env { command :: String -- ^ Program name+ , pwd :: String -- ^ Present Working Directory (PWD)+ , operands :: [String] -- ^ @trgdir@ @srcdir@ @[srcdir...]@+ , absolute :: Bool -- ^ @-a@, use absolute symbolic links+ , deBackstop :: Bool -- ^ @-d@, de-backstop trgdir+ , help :: Bool -- ^ @-h@, display help summary+ , license :: Bool -- ^ @-l@, display license terms+ , manual :: Bool -- ^ @-m@, display internal man page+ , noAction :: Bool -- ^ @-n@, take no action but trace steps+ , populate :: Bool -- ^ @-p@, populate trgdir with sub-directories+ , report :: Bool -- ^ @-r@, report final statistics+ , trace :: Bool -- ^ @-t@, trace steps+ , version :: Bool -- ^ @-v@, display version+ , synopsis :: Bool -- ^ @-y@, display manual synopsis+ } deriving Show++-- The default Environment+{- |+The defualt values, otherwise updated from the flags supplied on by+the command line options. The default program name is @backstop@.+All options flags are False or off by default.+-}+defaultEnv :: Environment+defaultEnv =+ Env { command = "backstop" -- Default program name+ , pwd = "" -- No PWD by default+ , operands = [] -- No operands by default+ , absolute = False -- False or off by default+ , deBackstop = False -- False or off by default+ , help = False -- False or off by default+ , license = False -- False or off by default+ , manual = False -- False or off by default+ , noAction = False -- False or off by default+ , populate = False -- False or off by default+ , report = False -- False or off by default+ , trace = False -- False or off by default+ , synopsis = False -- False or off by default+ , version = False -- False or off by default+ }
+ src/License.hs view
@@ -0,0 +1,691 @@+module License(putLicense) where++import System.Exit (exitWith)+import Utils (putOrPageStrLn)++-- | Display the license terms (GNU GPLv3).++putLicense :: IO ()+putLicense = putOrPageStrLn gpl30License >>= exitWith++-- | Derived from gpl-3.0.txt (GNU GENERAL PUBLIC LICENSE, Version 3,+-- 29 June 2007).++gpl30License :: String+gpl30License =+ " License terms: GNU GPL version 3 or any later version\n"+++ "\n"+++ " GNU GENERAL PUBLIC LICENSE\n"+++ " Version 3, 29 June 2007\n"+++ "\n"+++ " Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>\n"+++ " Everyone is permitted to copy and distribute verbatim copies\n"+++ " of this license document, but changing it is not allowed.\n"+++ "\n"+++ " Preamble\n"+++ "\n"+++ " The GNU General Public License is a free, copyleft license for\n"+++ "software and other kinds of works.\n"+++ "\n"+++ " The licenses for most software and other practical works are designed\n"+++ "to take away your freedom to share and change the works. By contrast,\n"+++ "the GNU General Public License is intended to guarantee your freedom to\n"+++ "share and change all versions of a program--to make sure it remains free\n"+++ "software for all its users. We, the Free Software Foundation, use the\n"+++ "GNU General Public License for most of our software; it applies also to\n"+++ "any other work released this way by its authors. You can apply it to\n"+++ "your programs, too.\n"+++ "\n"+++ " When we speak of free software, we are referring to freedom, not\n"+++ "price. Our General Public Licenses are designed to make sure that you\n"+++ "have the freedom to distribute copies of free software (and charge for\n"+++ "them if you wish), that you receive source code or can get it if you\n"+++ "want it, that you can change the software or use pieces of it in new\n"+++ "free programs, and that you know you can do these things.\n"+++ "\n"+++ " To protect your rights, we need to prevent others from denying you\n"+++ "these rights or asking you to surrender the rights. Therefore, you have\n"+++ "certain responsibilities if you distribute copies of the software, or if\n"+++ "you modify it: responsibilities to respect the freedom of others.\n"+++ "\n"+++ " For example, if you distribute copies of such a program, whether\n"+++ "gratis or for a fee, you must pass on to the recipients the same\n"+++ "freedoms that you received. You must make sure that they, too, receive\n"+++ "or can get the source code. And you must show them these terms so they\n"+++ "know their rights.\n"+++ "\n"+++ " Developers that use the GNU GPL protect your rights with two steps:\n"+++ "(1) assert copyright on the software, and (2) offer you this License\n"+++ "giving you legal permission to copy, distribute and/or modify it.\n"+++ "\n"+++ " For the developers' and authors' protection, the GPL clearly explains\n"+++ "that there is no warranty for this free software. For both users' and\n"+++ "authors' sake, the GPL requires that modified versions be marked as\n"+++ "changed, so that their problems will not be attributed erroneously to\n"+++ "authors of previous versions.\n"+++ "\n"+++ " Some devices are designed to deny users access to install or run\n"+++ "modified versions of the software inside them, although the manufacturer\n"+++ "can do so. This is fundamentally incompatible with the aim of\n"+++ "protecting users' freedom to change the software. The systematic\n"+++ "pattern of such abuse occurs in the area of products for individuals to\n"+++ "use, which is precisely where it is most unacceptable. Therefore, we\n"+++ "have designed this version of the GPL to prohibit the practice for those\n"+++ "products. If such problems arise substantially in other domains, we\n"+++ "stand ready to extend this provision to those domains in future versions\n"+++ "of the GPL, as needed to protect the freedom of users.\n"+++ "\n"+++ " Finally, every program is threatened constantly by software patents.\n"+++ "States should not allow patents to restrict development and use of\n"+++ "software on general-purpose computers, but in those that do, we wish to\n"+++ "avoid the special danger that patents applied to a free program could\n"+++ "make it effectively proprietary. To prevent this, the GPL assures that\n"+++ "patents cannot be used to render the program non-free.\n"+++ "\n"+++ " The precise terms and conditions for copying, distribution and\n"+++ "modification follow.\n"+++ "\n"+++ " TERMS AND CONDITIONS\n"+++ "\n"+++ " 0. Definitions.\n"+++ "\n"+++ " \"This License\" refers to version 3 of the GNU General Public License.\n"+++ "\n"+++ " \"Copyright\" also means copyright-like laws that apply to other kinds of\n"+++ "works, such as semiconductor masks.\n"+++ "\n"+++ " \"The Program\" refers to any copyrightable work licensed under this\n"+++ "License. Each licensee is addressed as \"you\". \"Licensees\" and\n"+++ "\"recipients\" may be individuals or organizations.\n"+++ "\n"+++ " To \"modify\" a work means to copy from or adapt all or part of the work\n"+++ "in a fashion requiring copyright permission, other than the making of an\n"+++ "exact copy. The resulting work is called a \"modified version\" of the\n"+++ "earlier work or a work \"based on\" the earlier work.\n"+++ "\n"+++ " A \"covered work\" means either the unmodified Program or a work based\n"+++ "on the Program.\n"+++ "\n"+++ " To \"propagate\" a work means to do anything with it that, without\n"+++ "permission, would make you directly or secondarily liable for\n"+++ "infringement under applicable copyright law, except executing it on a\n"+++ "computer or modifying a private copy. Propagation includes copying,\n"+++ "distribution (with or without modification), making available to the\n"+++ "public, and in some countries other activities as well.\n"+++ "\n"+++ " To \"convey\" a work means any kind of propagation that enables other\n"+++ "parties to make or receive copies. Mere interaction with a user through\n"+++ "a computer network, with no transfer of a copy, is not conveying.\n"+++ "\n"+++ " An interactive user interface displays \"Appropriate Legal Notices\"\n"+++ "to the extent that it includes a convenient and prominently visible\n"+++ "feature that (1) displays an appropriate copyright notice, and (2)\n"+++ "tells the user that there is no warranty for the work (except to the\n"+++ "extent that warranties are provided), that licensees may convey the\n"+++ "work under this License, and how to view a copy of this License. If\n"+++ "the interface presents a list of user commands or options, such as a\n"+++ "menu, a prominent item in the list meets this criterion.\n"+++ "\n"+++ " 1. Source Code.\n"+++ "\n"+++ " The \"source code\" for a work means the preferred form of the work\n"+++ "for making modifications to it. \"Object code\" means any non-source\n"+++ "form of a work.\n"+++ "\n"+++ " A \"Standard Interface\" means an interface that either is an official\n"+++ "standard defined by a recognized standards body, or, in the case of\n"+++ "interfaces specified for a particular programming language, one that\n"+++ "is widely used among developers working in that language.\n"+++ "\n"+++ " The \"System Libraries\" of an executable work include anything, other\n"+++ "than the work as a whole, that (a) is included in the normal form of\n"+++ "packaging a Major Component, but which is not part of that Major\n"+++ "Component, and (b) serves only to enable use of the work with that\n"+++ "Major Component, or to implement a Standard Interface for which an\n"+++ "implementation is available to the public in source code form. A\n"+++ "\"Major Component\", in this context, means a major essential component\n"+++ "(kernel, window system, and so on) of the specific operating system\n"+++ "(if any) on which the executable work runs, or a compiler used to\n"+++ "produce the work, or an object code interpreter used to run it.\n"+++ "\n"+++ " The \"Corresponding Source\" for a work in object code form means all\n"+++ "the source code needed to generate, install, and (for an executable\n"+++ "work) run the object code and to modify the work, including scripts to\n"+++ "control those activities. However, it does not include the work's\n"+++ "System Libraries, or general-purpose tools or generally available free\n"+++ "programs which are used unmodified in performing those activities but\n"+++ "which are not part of the work. For example, Corresponding Source\n"+++ "includes interface definition files associated with source files for\n"+++ "the work, and the source code for shared libraries and dynamically\n"+++ "linked subprograms that the work is specifically designed to require,\n"+++ "such as by intimate data communication or control flow between those\n"+++ "subprograms and other parts of the work.\n"+++ "\n"+++ " The Corresponding Source need not include anything that users\n"+++ "can regenerate automatically from other parts of the Corresponding\n"+++ "Source.\n"+++ "\n"+++ " The Corresponding Source for a work in source code form is that\n"+++ "same work.\n"+++ "\n"+++ " 2. Basic Permissions.\n"+++ "\n"+++ " All rights granted under this License are granted for the term of\n"+++ "copyright on the Program, and are irrevocable provided the stated\n"+++ "conditions are met. This License explicitly affirms your unlimited\n"+++ "permission to run the unmodified Program. The output from running a\n"+++ "covered work is covered by this License only if the output, given its\n"+++ "content, constitutes a covered work. This License acknowledges your\n"+++ "rights of fair use or other equivalent, as provided by copyright law.\n"+++ "\n"+++ " You may make, run and propagate covered works that you do not\n"+++ "convey, without conditions so long as your license otherwise remains\n"+++ "in force. You may convey covered works to others for the sole purpose\n"+++ "of having them make modifications exclusively for you, or provide you\n"+++ "with facilities for running those works, provided that you comply with\n"+++ "the terms of this License in conveying all material for which you do\n"+++ "not control copyright. Those thus making or running the covered works\n"+++ "for you must do so exclusively on your behalf, under your direction\n"+++ "and control, on terms that prohibit them from making any copies of\n"+++ "your copyrighted material outside their relationship with you.\n"+++ "\n"+++ " Conveying under any other circumstances is permitted solely under\n"+++ "the conditions stated below. Sublicensing is not allowed; section 10\n"+++ "makes it unnecessary.\n"+++ "\n"+++ " 3. Protecting Users' Legal Rights From Anti-Circumvention Law.\n"+++ "\n"+++ " No covered work shall be deemed part of an effective technological\n"+++ "measure under any applicable law fulfilling obligations under article\n"+++ "11 of the WIPO copyright treaty adopted on 20 December 1996, or\n"+++ "similar laws prohibiting or restricting circumvention of such\n"+++ "measures.\n"+++ "\n"+++ " When you convey a covered work, you waive any legal power to forbid\n"+++ "circumvention of technological measures to the extent such circumvention\n"+++ "is effected by exercising rights under this License with respect to\n"+++ "the covered work, and you disclaim any intention to limit operation or\n"+++ "modification of the work as a means of enforcing, against the work's\n"+++ "users, your or third parties' legal rights to forbid circumvention of\n"+++ "technological measures.\n"+++ "\n"+++ " 4. Conveying Verbatim Copies.\n"+++ "\n"+++ " You may convey verbatim copies of the Program's source code as you\n"+++ "receive it, in any medium, provided that you conspicuously and\n"+++ "appropriately publish on each copy an appropriate copyright notice;\n"+++ "keep intact all notices stating that this License and any\n"+++ "non-permissive terms added in accord with section 7 apply to the code;\n"+++ "keep intact all notices of the absence of any warranty; and give all\n"+++ "recipients a copy of this License along with the Program.\n"+++ "\n"+++ " You may charge any price or no price for each copy that you convey,\n"+++ "and you may offer support or warranty protection for a fee.\n"+++ "\n"+++ " 5. Conveying Modified Source Versions.\n"+++ "\n"+++ " You may convey a work based on the Program, or the modifications to\n"+++ "produce it from the Program, in the form of source code under the\n"+++ "terms of section 4, provided that you also meet all of these conditions:\n"+++ "\n"+++ " a) The work must carry prominent notices stating that you modified\n"+++ " it, and giving a relevant date.\n"+++ "\n"+++ " b) The work must carry prominent notices stating that it is\n"+++ " released under this License and any conditions added under section\n"+++ " 7. This requirement modifies the requirement in section 4 to\n"+++ " \"keep intact all notices\".\n"+++ "\n"+++ " c) You must license the entire work, as a whole, under this\n"+++ " License to anyone who comes into possession of a copy. This\n"+++ " License will therefore apply, along with any applicable section 7\n"+++ " additional terms, to the whole of the work, and all its parts,\n"+++ " regardless of how they are packaged. This License gives no\n"+++ " permission to license the work in any other way, but it does not\n"+++ " invalidate such permission if you have separately received it.\n"+++ "\n"+++ " d) If the work has interactive user interfaces, each must display\n"+++ " Appropriate Legal Notices; however, if the Program has interactive\n"+++ " interfaces that do not display Appropriate Legal Notices, your\n"+++ " work need not make them do so.\n"+++ "\n"+++ " A compilation of a covered work with other separate and independent\n"+++ "works, which are not by their nature extensions of the covered work,\n"+++ "and which are not combined with it such as to form a larger program,\n"+++ "in or on a volume of a storage or distribution medium, is called an\n"+++ "\"aggregate\" if the compilation and its resulting copyright are not\n"+++ "used to limit the access or legal rights of the compilation's users\n"+++ "beyond what the individual works permit. Inclusion of a covered work\n"+++ "in an aggregate does not cause this License to apply to the other\n"+++ "parts of the aggregate.\n"+++ "\n"+++ " 6. Conveying Non-Source Forms.\n"+++ "\n"+++ " You may convey a covered work in object code form under the terms\n"+++ "of sections 4 and 5, provided that you also convey the\n"+++ "machine-readable Corresponding Source under the terms of this License,\n"+++ "in one of these ways:\n"+++ "\n"+++ " a) Convey the object code in, or embodied in, a physical product\n"+++ " (including a physical distribution medium), accompanied by the\n"+++ " Corresponding Source fixed on a durable physical medium\n"+++ " customarily used for software interchange.\n"+++ "\n"+++ " b) Convey the object code in, or embodied in, a physical product\n"+++ " (including a physical distribution medium), accompanied by a\n"+++ " written offer, valid for at least three years and valid for as\n"+++ " long as you offer spare parts or customer support for that product\n"+++ " model, to give anyone who possesses the object code either (1) a\n"+++ " copy of the Corresponding Source for all the software in the\n"+++ " product that is covered by this License, on a durable physical\n"+++ " medium customarily used for software interchange, for a price no\n"+++ " more than your reasonable cost of physically performing this\n"+++ " conveying of source, or (2) access to copy the\n"+++ " Corresponding Source from a network server at no charge.\n"+++ "\n"+++ " c) Convey individual copies of the object code with a copy of the\n"+++ " written offer to provide the Corresponding Source. This\n"+++ " alternative is allowed only occasionally and noncommercially, and\n"+++ " only if you received the object code with such an offer, in accord\n"+++ " with subsection 6b.\n"+++ "\n"+++ " d) Convey the object code by offering access from a designated\n"+++ " place (gratis or for a charge), and offer equivalent access to the\n"+++ " Corresponding Source in the same way through the same place at no\n"+++ " further charge. You need not require recipients to copy the\n"+++ " Corresponding Source along with the object code. If the place to\n"+++ " copy the object code is a network server, the Corresponding Source\n"+++ " may be on a different server (operated by you or a third party)\n"+++ " that supports equivalent copying facilities, provided you maintain\n"+++ " clear directions next to the object code saying where to find the\n"+++ " Corresponding Source. Regardless of what server hosts the\n"+++ " Corresponding Source, you remain obligated to ensure that it is\n"+++ " available for as long as needed to satisfy these requirements.\n"+++ "\n"+++ " e) Convey the object code using peer-to-peer transmission, provided\n"+++ " you inform other peers where the object code and Corresponding\n"+++ " Source of the work are being offered to the general public at no\n"+++ " charge under subsection 6d.\n"+++ "\n"+++ " A separable portion of the object code, whose source code is excluded\n"+++ "from the Corresponding Source as a System Library, need not be\n"+++ "included in conveying the object code work.\n"+++ "\n"+++ " A \"User Product\" is either (1) a \"consumer product\", which means any\n"+++ "tangible personal property which is normally used for personal, family,\n"+++ "or household purposes, or (2) anything designed or sold for incorporation\n"+++ "into a dwelling. In determining whether a product is a consumer product,\n"+++ "doubtful cases shall be resolved in favor of coverage. For a particular\n"+++ "product received by a particular user, \"normally used\" refers to a\n"+++ "typical or common use of that class of product, regardless of the status\n"+++ "of the particular user or of the way in which the particular user\n"+++ "actually uses, or expects or is expected to use, the product. A product\n"+++ "is a consumer product regardless of whether the product has substantial\n"+++ "commercial, industrial or non-consumer uses, unless such uses represent\n"+++ "the only significant mode of use of the product.\n"+++ "\n"+++ " \"Installation Information\" for a User Product means any methods,\n"+++ "procedures, authorization keys, or other information required to install\n"+++ "and execute modified versions of a covered work in that User Product from\n"+++ "a modified version of its Corresponding Source. The information must\n"+++ "suffice to ensure that the continued functioning of the modified object\n"+++ "code is in no case prevented or interfered with solely because\n"+++ "modification has been made.\n"+++ "\n"+++ " If you convey an object code work under this section in, or with, or\n"+++ "specifically for use in, a User Product, and the conveying occurs as\n"+++ "part of a transaction in which the right of possession and use of the\n"+++ "User Product is transferred to the recipient in perpetuity or for a\n"+++ "fixed term (regardless of how the transaction is characterized), the\n"+++ "Corresponding Source conveyed under this section must be accompanied\n"+++ "by the Installation Information. But this requirement does not apply\n"+++ "if neither you nor any third party retains the ability to install\n"+++ "modified object code on the User Product (for example, the work has\n"+++ "been installed in ROM).\n"+++ "\n"+++ " The requirement to provide Installation Information does not include a\n"+++ "requirement to continue to provide support service, warranty, or updates\n"+++ "for a work that has been modified or installed by the recipient, or for\n"+++ "the User Product in which it has been modified or installed. Access to a\n"+++ "network may be denied when the modification itself materially and\n"+++ "adversely affects the operation of the network or violates the rules and\n"+++ "protocols for communication across the network.\n"+++ "\n"+++ " Corresponding Source conveyed, and Installation Information provided,\n"+++ "in accord with this section must be in a format that is publicly\n"+++ "documented (and with an implementation available to the public in\n"+++ "source code form), and must require no special password or key for\n"+++ "unpacking, reading or copying.\n"+++ "\n"+++ " 7. Additional Terms.\n"+++ "\n"+++ " \"Additional permissions\" are terms that supplement the terms of this\n"+++ "License by making exceptions from one or more of its conditions.\n"+++ "Additional permissions that are applicable to the entire Program shall\n"+++ "be treated as though they were included in this License, to the extent\n"+++ "that they are valid under applicable law. If additional permissions\n"+++ "apply only to part of the Program, that part may be used separately\n"+++ "under those permissions, but the entire Program remains governed by\n"+++ "this License without regard to the additional permissions.\n"+++ "\n"+++ " When you convey a copy of a covered work, you may at your option\n"+++ "remove any additional permissions from that copy, or from any part of\n"+++ "it. (Additional permissions may be written to require their own\n"+++ "removal in certain cases when you modify the work.) You may place\n"+++ "additional permissions on material, added by you to a covered work,\n"+++ "for which you have or can give appropriate copyright permission.\n"+++ "\n"+++ " Notwithstanding any other provision of this License, for material you\n"+++ "add to a covered work, you may (if authorized by the copyright holders of\n"+++ "that material) supplement the terms of this License with terms:\n"+++ "\n"+++ " a) Disclaiming warranty or limiting liability differently from the\n"+++ " terms of sections 15 and 16 of this License; or\n"+++ "\n"+++ " b) Requiring preservation of specified reasonable legal notices or\n"+++ " author attributions in that material or in the Appropriate Legal\n"+++ " Notices displayed by works containing it; or\n"+++ "\n"+++ " c) Prohibiting misrepresentation of the origin of that material, or\n"+++ " requiring that modified versions of such material be marked in\n"+++ " reasonable ways as different from the original version; or\n"+++ "\n"+++ " d) Limiting the use for publicity purposes of names of licensors or\n"+++ " authors of the material; or\n"+++ "\n"+++ " e) Declining to grant rights under trademark law for use of some\n"+++ " trade names, trademarks, or service marks; or\n"+++ "\n"+++ " f) Requiring indemnification of licensors and authors of that\n"+++ " material by anyone who conveys the material (or modified versions of\n"+++ " it) with contractual assumptions of liability to the recipient, for\n"+++ " any liability that these contractual assumptions directly impose on\n"+++ " those licensors and authors.\n"+++ "\n"+++ " All other non-permissive additional terms are considered \"further\n"+++ "restrictions\" within the meaning of section 10. If the Program as you\n"+++ "received it, or any part of it, contains a notice stating that it is\n"+++ "governed by this License along with a term that is a further\n"+++ "restriction, you may remove that term. If a license document contains\n"+++ "a further restriction but permits relicensing or conveying under this\n"+++ "License, you may add to a covered work material governed by the terms\n"+++ "of that license document, provided that the further restriction does\n"+++ "not survive such relicensing or conveying.\n"+++ "\n"+++ " If you add terms to a covered work in accord with this section, you\n"+++ "must place, in the relevant source files, a statement of the\n"+++ "additional terms that apply to those files, or a notice indicating\n"+++ "where to find the applicable terms.\n"+++ "\n"+++ " Additional terms, permissive or non-permissive, may be stated in the\n"+++ "form of a separately written license, or stated as exceptions;\n"+++ "the above requirements apply either way.\n"+++ "\n"+++ " 8. Termination.\n"+++ "\n"+++ " You may not propagate or modify a covered work except as expressly\n"+++ "provided under this License. Any attempt otherwise to propagate or\n"+++ "modify it is void, and will automatically terminate your rights under\n"+++ "this License (including any patent licenses granted under the third\n"+++ "paragraph of section 11).\n"+++ "\n"+++ " However, if you cease all violation of this License, then your\n"+++ "license from a particular copyright holder is reinstated (a)\n"+++ "provisionally, unless and until the copyright holder explicitly and\n"+++ "finally terminates your license, and (b) permanently, if the copyright\n"+++ "holder fails to notify you of the violation by some reasonable means\n"+++ "prior to 60 days after the cessation.\n"+++ "\n"+++ " Moreover, your license from a particular copyright holder is\n"+++ "reinstated permanently if the copyright holder notifies you of the\n"+++ "violation by some reasonable means, this is the first time you have\n"+++ "received notice of violation of this License (for any work) from that\n"+++ "copyright holder, and you cure the violation prior to 30 days after\n"+++ "your receipt of the notice.\n"+++ "\n"+++ " Termination of your rights under this section does not terminate the\n"+++ "licenses of parties who have received copies or rights from you under\n"+++ "this License. If your rights have been terminated and not permanently\n"+++ "reinstated, you do not qualify to receive new licenses for the same\n"+++ "material under section 10.\n"+++ "\n"+++ " 9. Acceptance Not Required for Having Copies.\n"+++ "\n"+++ " You are not required to accept this License in order to receive or\n"+++ "run a copy of the Program. Ancillary propagation of a covered work\n"+++ "occurring solely as a consequence of using peer-to-peer transmission\n"+++ "to receive a copy likewise does not require acceptance. However,\n"+++ "nothing other than this License grants you permission to propagate or\n"+++ "modify any covered work. These actions infringe copyright if you do\n"+++ "not accept this License. Therefore, by modifying or propagating a\n"+++ "covered work, you indicate your acceptance of this License to do so.\n"+++ "\n"+++ " 10. Automatic Licensing of Downstream Recipients.\n"+++ "\n"+++ " Each time you convey a covered work, the recipient automatically\n"+++ "receives a license from the original licensors, to run, modify and\n"+++ "propagate that work, subject to this License. You are not responsible\n"+++ "for enforcing compliance by third parties with this License.\n"+++ "\n"+++ " An \"entity transaction\" is a transaction transferring control of an\n"+++ "organization, or substantially all assets of one, or subdividing an\n"+++ "organization, or merging organizations. If propagation of a covered\n"+++ "work results from an entity transaction, each party to that\n"+++ "transaction who receives a copy of the work also receives whatever\n"+++ "licenses to the work the party's predecessor in interest had or could\n"+++ "give under the previous paragraph, plus a right to possession of the\n"+++ "Corresponding Source of the work from the predecessor in interest, if\n"+++ "the predecessor has it or can get it with reasonable efforts.\n"+++ "\n"+++ " You may not impose any further restrictions on the exercise of the\n"+++ "rights granted or affirmed under this License. For example, you may\n"+++ "not impose a license fee, royalty, or other charge for exercise of\n"+++ "rights granted under this License, and you may not initiate litigation\n"+++ "(including a cross-claim or counterclaim in a lawsuit) alleging that\n"+++ "any patent claim is infringed by making, using, selling, offering for\n"+++ "sale, or importing the Program or any portion of it.\n"+++ "\n"+++ " 11. Patents.\n"+++ "\n"+++ " A \"contributor\" is a copyright holder who authorizes use under this\n"+++ "License of the Program or a work on which the Program is based. The\n"+++ "work thus licensed is called the contributor's \"contributor version\".\n"+++ "\n"+++ " A contributor's \"essential patent claims\" are all patent claims\n"+++ "owned or controlled by the contributor, whether already acquired or\n"+++ "hereafter acquired, that would be infringed by some manner, permitted\n"+++ "by this License, of making, using, or selling its contributor version,\n"+++ "but do not include claims that would be infringed only as a\n"+++ "consequence of further modification of the contributor version. For\n"+++ "purposes of this definition, \"control\" includes the right to grant\n"+++ "patent sublicenses in a manner consistent with the requirements of\n"+++ "this License.\n"+++ "\n"+++ " Each contributor grants you a non-exclusive, worldwide, royalty-free\n"+++ "patent license under the contributor's essential patent claims, to\n"+++ "make, use, sell, offer for sale, import and otherwise run, modify and\n"+++ "propagate the contents of its contributor version.\n"+++ "\n"+++ " In the following three paragraphs, a \"patent license\" is any express\n"+++ "agreement or commitment, however denominated, not to enforce a patent\n"+++ "(such as an express permission to practice a patent or covenant not to\n"+++ "sue for patent infringement). To \"grant\" such a patent license to a\n"+++ "party means to make such an agreement or commitment not to enforce a\n"+++ "patent against the party.\n"+++ "\n"+++ " If you convey a covered work, knowingly relying on a patent license,\n"+++ "and the Corresponding Source of the work is not available for anyone\n"+++ "to copy, free of charge and under the terms of this License, through a\n"+++ "publicly available network server or other readily accessible means,\n"+++ "then you must either (1) cause the Corresponding Source to be so\n"+++ "available, or (2) arrange to deprive yourself of the benefit of the\n"+++ "patent license for this particular work, or (3) arrange, in a manner\n"+++ "consistent with the requirements of this License, to extend the patent\n"+++ "license to downstream recipients. \"Knowingly relying\" means you have\n"+++ "actual knowledge that, but for the patent license, your conveying the\n"+++ "covered work in a country, or your recipient's use of the covered work\n"+++ "in a country, would infringe one or more identifiable patents in that\n"+++ "country that you have reason to believe are valid.\n"+++ "\n"+++ " If, pursuant to or in connection with a single transaction or\n"+++ "arrangement, you convey, or propagate by procuring conveyance of, a\n"+++ "covered work, and grant a patent license to some of the parties\n"+++ "receiving the covered work authorizing them to use, propagate, modify\n"+++ "or convey a specific copy of the covered work, then the patent license\n"+++ "you grant is automatically extended to all recipients of the covered\n"+++ "work and works based on it.\n"+++ "\n"+++ " A patent license is \"discriminatory\" if it does not include within\n"+++ "the scope of its coverage, prohibits the exercise of, or is\n"+++ "conditioned on the non-exercise of one or more of the rights that are\n"+++ "specifically granted under this License. You may not convey a covered\n"+++ "work if you are a party to an arrangement with a third party that is\n"+++ "in the business of distributing software, under which you make payment\n"+++ "to the third party based on the extent of your activity of conveying\n"+++ "the work, and under which the third party grants, to any of the\n"+++ "parties who would receive the covered work from you, a discriminatory\n"+++ "patent license (a) in connection with copies of the covered work\n"+++ "conveyed by you (or copies made from those copies), or (b) primarily\n"+++ "for and in connection with specific products or compilations that\n"+++ "contain the covered work, unless you entered into that arrangement,\n"+++ "or that patent license was granted, prior to 28 March 2007.\n"+++ "\n"+++ " Nothing in this License shall be construed as excluding or limiting\n"+++ "any implied license or other defenses to infringement that may\n"+++ "otherwise be available to you under applicable patent law.\n"+++ "\n"+++ " 12. No Surrender of Others' Freedom.\n"+++ "\n"+++ " If conditions are imposed on you (whether by court order, agreement or\n"+++ "otherwise) that contradict the conditions of this License, they do not\n"+++ "excuse you from the conditions of this License. If you cannot convey a\n"+++ "covered work so as to satisfy simultaneously your obligations under this\n"+++ "License and any other pertinent obligations, then as a consequence you may\n"+++ "not convey it at all. For example, if you agree to terms that obligate you\n"+++ "to collect a royalty for further conveying from those to whom you convey\n"+++ "the Program, the only way you could satisfy both those terms and this\n"+++ "License would be to refrain entirely from conveying the Program.\n"+++ "\n"+++ " 13. Use with the GNU Affero General Public License.\n"+++ "\n"+++ " Notwithstanding any other provision of this License, you have\n"+++ "permission to link or combine any covered work with a work licensed\n"+++ "under version 3 of the GNU Affero General Public License into a single\n"+++ "combined work, and to convey the resulting work. The terms of this\n"+++ "License will continue to apply to the part which is the covered work,\n"+++ "but the special requirements of the GNU Affero General Public License,\n"+++ "section 13, concerning interaction through a network will apply to the\n"+++ "combination as such.\n"+++ "\n"+++ " 14. Revised Versions of this License.\n"+++ "\n"+++ " The Free Software Foundation may publish revised and/or new versions of\n"+++ "the GNU General Public License from time to time. Such new versions will\n"+++ "be similar in spirit to the present version, but may differ in detail to\n"+++ "address new problems or concerns.\n"+++ "\n"+++ " Each version is given a distinguishing version number. If the\n"+++ "Program specifies that a certain numbered version of the GNU General\n"+++ "Public License \"or any later version\" applies to it, you have the\n"+++ "option of following the terms and conditions either of that numbered\n"+++ "version or of any later version published by the Free Software\n"+++ "Foundation. If the Program does not specify a version number of the\n"+++ "GNU General Public License, you may choose any version ever published\n"+++ "by the Free Software Foundation.\n"+++ "\n"+++ " If the Program specifies that a proxy can decide which future\n"+++ "versions of the GNU General Public License can be used, that proxy's\n"+++ "public statement of acceptance of a version permanently authorizes you\n"+++ "to choose that version for the Program.\n"+++ "\n"+++ " Later license versions may give you additional or different\n"+++ "permissions. However, no additional obligations are imposed on any\n"+++ "author or copyright holder as a result of your choosing to follow a\n"+++ "later version.\n"+++ "\n"+++ " 15. Disclaimer of Warranty.\n"+++ "\n"+++ " THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY\n"+++ "APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT\n"+++ "HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM \"AS IS\" WITHOUT WARRANTY\n"+++ "OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,\n"+++ "THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR\n"+++ "PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM\n"+++ "IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF\n"+++ "ALL NECESSARY SERVICING, REPAIR OR CORRECTION.\n"+++ "\n"+++ " 16. Limitation of Liability.\n"+++ "\n"+++ " IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING\n"+++ "WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS\n"+++ "THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY\n"+++ "GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE\n"+++ "USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF\n"+++ "DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD\n"+++ "PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),\n"+++ "EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF\n"+++ "SUCH DAMAGES.\n"+++ "\n"+++ " 17. Interpretation of Sections 15 and 16.\n"+++ "\n"+++ " If the disclaimer of warranty and limitation of liability provided\n"+++ "above cannot be given local legal effect according to their terms,\n"+++ "reviewing courts shall apply local law that most closely approximates\n"+++ "an absolute waiver of all civil liability in connection with the\n"+++ "Program, unless a warranty or assumption of liability accompanies a\n"+++ "copy of the Program in return for a fee.\n"+++ "\n"+++ " END OF TERMS AND CONDITIONS\n"+++ "\n"+++ " How to Apply These Terms to Your New Programs\n"+++ "\n"+++ " If you develop a new program, and you want it to be of the greatest\n"+++ "possible use to the public, the best way to achieve this is to make it\n"+++ "free software which everyone can redistribute and change under these terms.\n"+++ "\n"+++ " To do so, attach the following notices to the program. It is safest\n"+++ "to attach them to the start of each source file to most effectively\n"+++ "state the exclusion of warranty; and each file should have at least\n"+++ "the \"copyright\" line and a pointer to where the full notice is found.\n"+++ "\n"+++ " <one line to give the program's name and a brief idea of what it does.>\n"+++ " Copyright (C) <year> <name of author>\n"+++ "\n"+++ " This program is free software: you can redistribute it and/or modify\n"+++ " it under the terms of the GNU General Public License as published by\n"+++ " the Free Software Foundation, either version 3 of the License, or\n"+++ " (at your option) any later version.\n"+++ "\n"+++ " This program is distributed in the hope that it will be useful,\n"+++ " but WITHOUT ANY WARRANTY; without even the implied warranty of\n"+++ " MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the\n"+++ " GNU General Public License for more details.\n"+++ "\n"+++ " You should have received a copy of the GNU General Public License\n"+++ " along with this program. If not, see <http://www.gnu.org/licenses/>.\n"+++ "\n"+++ "Also add information on how to contact you by electronic and paper mail.\n"+++ "\n"+++ " If the program does terminal interaction, make it output a short\n"+++ "notice like this when it starts in an interactive mode:\n"+++ "\n"+++ " <program> Copyright (C) <year> <name of author>\n"+++ " This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.\n"+++ " This is free software, and you are welcome to redistribute it\n"+++ " under certain conditions; type `show c' for details.\n"+++ "\n"+++ "The hypothetical commands `show w' and `show c' should show the appropriate\n"+++ "parts of the General Public License. Of course, your program's commands\n"+++ "might be different; for a GUI interface, you would use an \"about box\".\n"+++ "\n"+++ " You should also get your employer (if you work as a programmer) or school,\n"+++ "if any, to sign a \"copyright disclaimer\" for the program, if necessary.\n"+++ "For more information on this, and how to apply and follow the GNU GPL, see\n"+++ "<http://www.gnu.org/licenses/>.\n"+++ "\n"+++ " The GNU General Public License does not permit incorporating your program\n"+++ "into proprietary programs. If your program is a subroutine library, you\n"+++ "may consider it more useful to permit linking proprietary applications with\n"+++ "the library. If this is what you want to do, use the GNU Lesser General\n"+++ "Public License instead of this License. But first, please read\n"+++ "<http://www.gnu.org/philosophy/why-not-lgpl.html>.\n"
+ src/Main.hs view
@@ -0,0 +1,494 @@++{- |+> backstop(1) User Commands backstop(1)+> +> NAME+> backstop - Backstop a target directory by source directories+> +> SYNOPSIS+> backstop [-nprt] [-a|-d] trgdir srcdir [srcdir ...]+> backstop -h+> backstop -l+> backstop -m+> backstop -v+> backstop -y+> +> AVAILABILITY+> Marcus D. Gabriel (c)1999-2017. All rights reserved.+> +> marcus@gabriel.name+> +> License terms: GNU GPL version 3 or later (backstop -l)+> +> DESCRIPTION+> Backstop a target directory by source directories thereby+> creating a backing chain using relative symbolic links by default+> or absolute symbolic links by option. If more than one source+> directory is given, backstop the target directory with each+> source directory in turn starting from left to right on the+> command line.+> +> Intuitively, backstop fills in the missing objects or holes that+> exist in the target directory relative to the source directories+> thereby creating a merged view of the target and source+> directories.+> +> De-backstop a target directory by its source directories. In+> this case, the source directories no longer need to exist. If+> more than one source directory is given, de-backstop the target+> directory by the source directories.+> +> Symbolic links are never followed. However, the target and+> source directories are canonicalized (realpath(3)) internally by+> the command backstop before backstopping and de-backstoppoing.+> +> By default no output is displayed except possibly to STDERR.+> +> ALGORITHM+> There must be at least two arguments or operands. The first+> operand is the target directory, and the second operand and+> beyond are source directories. The target and source directory+> must be parallel directories, that is, neither canonicalized+> (realpath(3)) directory path may be a sub-directory of the other.+> If the above is not true, a usage error occurs.+> +> Nevertheless, pathnames are internally in reduced form such that+> symbolic link names are treated literally when finding directory+> names. See "cd -L" of ksh(1). In other words, components in the+> pathname that are not directories but symbolic links to+> directories are not resolved to their corresponding directories.+> +> A list of objects or names is collected under the root of the+> source directory excluding the directory dot (.) and the+> directory double-dot (..). If the list is empty, the algorithm+> is done, otherwise the objects divide into two classes, objects+> that are not directories and objects that are directories. There+> are five possibilities:+> +> 1. The object is either dot (.) or double-dot (..) whereupon no+> action is taken.+> +> 2. If an object of the same name as the name of the object under+> the root of the source directory does not exists under the+> root of the target directory, then a symbolic link, relative+> or absolute as required, is created under the root of the+> target directory to the object under the root of the source+> directory. If populating (-p) and the object under the root+> of the source directory is a directory, then a sub-directory+> is created instead.+> +> 3. If an object of the same name as the name of the object under+> the root of the source directory does exists under the root of+> the target directory and is a file, no action is taken,+> regardless of whether or not the object under the root of the+> source directory is a file or a directory.+> +> 4. If an object of the same name as the name of the object under+> the root of the source directory does exists under the root of+> the target directory and is a directory, and if the object of+> the same name under the root of the source directory is a+> file, no action is taken.+> +> 5. If an object of the same name as the name of the object under+> the root of the source directory does exists under the root of+> the target directory and is a directory, and if the object of+> the same name under the root of the source directory is also a+> directory, then recursion occurs with the objects of the same+> name under the roots of the target and source directories as+> new root target and source directories, respectively.+> +> When de-backstopping a target directory by source directories,+> the sources no longer need to exist. Symbolic links under the+> target are removed if and only if they point to a pahtname under+> one of the source directories. This can be determined even if+> the source directory no longer exists because symbolic links+> within directory pathnames are taken literally. See "cd -L" of+> ksh(1).+> +> When de-populating while de-backstopping (-pd), a directory is+> removed if all objects within the directory are symbolic links+> that have been remove while de-backstopping. An empty directory+> is removed if and only if there exists a corresponding directory+> path under one of the source directories as under the target+> directory. This can only be determined if the source directory+> and correponding sub-directory still exist. If not, then no+> action is taken.+> +> OPTIONS+> The following options are supported:+> +> -a Create symbolic links which are absolute paths.+> +> -d De-backstop the target directory by its source directories.+> The -a option has no affect on the -d option.+> +> -h Display a short command summary.+> +> -l Display the backstop license terms.+> +> -m Display this internal manual page.+> +> -n Take no action but trace possible program execution. The -n+> option implies the -t option.+> +> -p Populate the target by making equivalent sub-directories of+> the source sub-directories instead of symbolic links for these+> sub-directories that point back into the sources. For+> example, if the target directory is empty, then for a set of+> source directories, from left to right on the command line,+> this creates a combined directory structure of the sources+> under the target directory in which all non-directories are+> symbolic links pointing back into the source directories.+> This is similar to the lndir(1) command of the X consortium.+> +> With the -d option, all sub-directories emptied of symbolic+> links under the target directory are removed, and all empty+> directories are removed if and only if the correspoding+> sub-directory under the source directory exists.+> +> -r Report the number of symbolic links and directories created,+> the number of calls and maximum depth of backstop, the+> maximum breadth observed by backstop, and the number of non-+> fatal errors encountered. With the -d option, show the+> number of symbolic links and directories removed.+> +> -t Show the trace of program execution. The output is a list+> of executable commands.+> +> -v The version of backstop.+> +> -y A synopsis of the internal manual page.+> +> OPERANDS+> trgdir+> The directory that will be backed by other directories. The+> target directory can be backed by multiple source directories+> where each source directory could be backed by yet another+> directory or multiple directories thereby creating an+> extensible backing chain.+> +> srcdir+> The directory which backs a target directory. The source+> directory can be backed by multiple additional directories+> where each additional directory could be backed by yet another+> directory or multiple directories thereby creating an+> extensible backing chain.+> +> USAGE NOTES+> Evolved with ghc 6.10, 6.12, 7.0, 7.4, 7.10, 8.0.2, and 8.4.1.+> Tested with 8.4.1.+> +> EXAMPLES+> To display a summary of usage, use+> +> backstop -h+> +> To display a synopsis of this internal manual page, use+> +> backstop -y+> +> To display this internal manual page, use+> +> backstop -m+> +> To trace program execution, use+> +> backstop -t /export/install/sparc/devlopment/modules \+> /export/install/sparc/modules+> +> To trace program execution taking no action, use+> +> backstop -n /export/install/sparc/devlopment/modules \+> /export/install/sparc/modules+> +> To back /export/install/sparc/devlopment/modules with+> /export/install/sparc/modules using relative symbolic links, use+> +> backstop /export/install/sparc/devlopment/modules \+> /export/install/sparc/modules+> +> To back /export/install/sparc/devlopment/modules with+> /export/install/sparc/modules using absolute symbolic links, use+> +> backstop -a /export/install/sparc/devlopment/modules \+> /export/install/sparc/modules+> +> To stop backing /export/install/sparc/devlopment/modules with+> /export/install/sparc/modules, use+> +> backstop -d /export/install/sparc/devlopment/modules \+> /export/install/sparc/modules+> +> ENVIRONMENT VARIABLES+> PAGER Page the internal manual page or license terms+> using "${PAGER}", otherwise print it.+> +> EXIT STATUS+> An exit status of 0 is returned if successful, otherwise non-zero+> is returned. The following error exit codes are used by+> backstop:+> +> EXIT CODE MEANING+> 251 Less than two operands.+> 252 Not a directory, that is, trgdir or one or more+> of the srcdir are not a directory.+> 253 Not parallel directories, that is, a srcdir is+> a sub-directory of trgdir or vice versa, or one+> of the srcdir is a sub-directory of another+> srcdir.+> 254 Not yet implemented.+> 255 Non-fatal errors occurred. Error messages are+> sent to STDERR for each non-fatal error that+> occurred with return code equal to the number of+> non-falal errors if less than 251, otherwise the+> return code is 255, that is, "infinity".+> +> FILES+> N/A.+> +> SEE ALSO+> ln(1), mkdir(1), rm(1), rmdir(1), ksh(1), lndir(1), realpath(3)+> +> "Source Control to Project Control: Applying RCS and SCCS" by Don+> Bolinger and Tan Bronson. ISBN 1-56592-117-8.+> +> NOTES+> Please send bug reports to marcus@gabriel.name.+> +> BUGS+> No known bugs to date.+-}++module Main(main) where+++-- Section: imports+import Backstop (backstop)+import Control.Exception (try,IOException(..))+import Control.Monad (when,unless,filterM)+import Data.List (intercalate)+import Environment (Environment(..),defaultEnv)+import License (putLicense)+import Manual (putManual)+import System.Console.GetOpt (ArgDescr(..),OptDescr(..),ArgOrder(..),usageInfo,getOpt)+import System.Directory (getCurrentDirectory,canonicalizePath)+import System.Environment (getEnvironment,getProgName,getArgs)+import System.Exit (exitSuccess,exitWith,ExitCode(..))+import System.FilePath (takeFileName)+import System.IO (stderr,stdout,hPutStrLn,Handle(..))+import Utils (reduceFilePath,pairs,subdirectories,aDirectory)++-- Section: main: No need to change this section.+{- | Backstop a target directory by source directories. Refer to+'backstop'@ -h@, 'backstop'@ -y@, or 'backstop'@ -m@ for more information.+-}+main :: IO ()+main =+ do cmdLine <- getArgs+ progName <- getProgName+ case getOpt (argOrder config) options cmdLine of+ (opts, args, []) -> runCmd $ foldl updateEnvField env opts+ where env = defaultEnv{command=takeFileName progName,operands=args}+ (_, _, errs) -> error $ concat errs ++ usageInfo (header progName) options+++-- Section: summary, help, version: No need to change this section.+{- |+Given the programe name, returns the program name and the release+version.+-}+versionHeader :: String -> String+versionHeader progName = takeFileName progName ++ " release " ++ release config++{- |+Given the program name, returns a synopis of options.+-}+header :: String -> String+header progName = versionHeader (takeFileName progName) +++ "\nusage: " ++ takeFileName progName ++ flagsOps config++{- |+Puts the program name and its version.+-}+putVersion :: IO ()+putVersion = do progName <- getProgName+ putStrLn (versionHeader progName)+ exitSuccess++{- |+Puts the program name and the synopsis of options to handle (stdout or+stderr) with the supplied the exit code.+-}+putSynopsis :: Handle -> String -> ExitCode -> IO ()+putSynopsis h s e = do progName <- getProgName+ hPutStrLn h (takeFileName progName ++ ": " ++ s ++ header progName)+ exitWith e++{- |+Puts the program name and a short summary.+-}+putSummary :: IO ()+putSummary = do progName <- getProgName+ putStrLn (usageInfo (header progName) options)+ exitSuccess+++-- Section: configuration (to be configured)+{- |+Configuration information is initial, constant information, that is,+not needing updates.+-}+data Configuration =+ Config {+ argOrder :: ArgOrder Flag,+ release :: String,+ flagsOps :: String+ }++{- |+To be configured once with the versions number and synopsis. Other+items may of course be added to the configuration as needed.+-}+config :: Configuration+config =+ Config {+ argOrder = RequireOrder,+ -- Update revision number: toggle case+ release = "1.3.0.352",+ flagsOps = " {-{h|l|m|v|y}|[-nprt] [-a|-d] trgdir srcdir [srcdir...]}"+ }+ where+ revision =+ let num = flip elem ['0'..'9']+ in reverse.dropWhile (not.num).reverse.dropWhile (not.num)+++-- Section: options (to be configured)+{- |+Flags set as a function of the command line options supplied.+-}+data Flag = Absolute | DeBackstop | Help | License |+ Manual | NoAction | Populate | Report | Trace |+ Synopsis | Version++{- |+Options that can be given on the command line.+-}+options :: [OptDescr Flag]+options =+ [+ Option "a" ["absolute"] (NoArg Absolute) "Make absolute symbolic links",+ Option "d" ["de-backstop"] (NoArg DeBackstop) "De-backstop target given sources",+ Option "h" ["help"] (NoArg Help) "Help summary",+ Option "l" ["license"] (NoArg License) "License terms",+ Option "m" ["manual"] (NoArg Manual) "Manual page",+ Option "n" ["no-action"] (NoArg NoAction) "No-action trace",+ Option "p" ["populate"] (NoArg Populate) "Populate by making sub-directories",+ Option "r" ["report"] (NoArg Report) "Report final statistics",+ Option "t" ["trace"] (NoArg Trace) "Trace program execution",+ Option "v" ["version"] (NoArg Version) "Version of backstop",+ Option "y" ["synopsis"] (NoArg Synopsis) "Help synopsis"+ ]+++-- Section: updating a field in the environment (to be configured)+{- |+Every option, and only an option, must be able to be updated here.+-}+updateEnvField :: Environment -> Flag -> Environment+updateEnvField env opt =+ case opt of+ Absolute -> env{absolute = True}+ DeBackstop -> env{deBackstop = True}+ Help -> env{help = True}+ License -> env{license = True}+ Manual -> env{manual = True}+ NoAction -> env{noAction = True}+ Populate -> env{populate = True}+ Report -> env{report = True}+ Trace -> env{trace = True}+ Synopsis -> env{synopsis = True}+ Version -> env{version = True}+-- _ -> error (command env ++ ": updateEnvField: unknown error")+++-- Section: running the command given the environment (to be configured)+{- |++No need to change the function runCmd.++Update the environment with updateEnv, verify the environment with+verifyEnv, resolve option conflicts with resolveEnv, and run the+command given the environemnt with runWith which does the actual work+where the thre reall usually imported from a module.+-}+runCmd :: Environment -> IO ()+runCmd env+ | synopsis env = putSynopsis stdout "\r" ExitSuccess+ | help env = putSummary+ | version env = putVersion+ | manual env = putManual+ | license env = putLicense+ | otherwise =+ do env_ <- updateEnv env+ verifyEnv env_+ runWith (resolveEnv env_)++{- |+'updateEnv' updates the environment ('Environment') from the universe,+the external environment.+-}+updateEnv :: Environment -> IO Environment+updateEnv env = do cd <- getCurrentDirectory+ es <- getEnvironment+ os <- mapM canonicalizePath (operands env)+ let pd = lookup "PWD" es+ e' = maybe env{pwd = cd} (\pd -> env{pwd = pd}) pd+ return e'{operands = os}++{- |+'verifyEnv' verifies the environment created from the command line+options and the supplied operands.+-}+verifyEnv :: Environment -> IO ()+verifyEnv env = verify1 env >> verify2 env >> verify3 env+ where+ verify1 env =+ when (length (operands env) < 2) $+ putSynopsis stderr "less than two operands\n" (ExitFailure 251)+ verify2 env =+ do let ops = if deBackstop env then [(head.operands) env] else operands env+ ps <- filterM (fmap not . aDirectory) ops+ let errMsg s = putSynopsis stderr (s++(unwords ps++"\n")) (ExitFailure 252)+ unless (null ps) $+ errMsg $ if length ps == 1 then "not a directory: " else "not directories: "+ verify3 env =+ do ds <- mapM canonicalizePath (operands env)+ let ps = filter (uncurry subdirectories) $ pairs ds+ let errMsg = intercalate "\n " $ map (\ (x,y) -> "("++x++","++y++")") ps+ unless (null ps) $+ putSynopsis stderr ("not parallel directories:\n "++errMsg++"\n") (ExitFailure 253)++{- |+'resolveEnv' resolves the environment created from the command line+options and the supplied operands, e.g., if an option over-rides+another, 'resolveEnv' takes this into account.+-}+resolveEnv :: Environment -> Environment+-- Order is important, so please do not change it without study+resolveEnv = resolveEnv2 . resolveEnv1+ where+ -- The -n option implies -t+ resolveEnv1 env =+ if noAction env+ then env{trace = True}+ else env+ -- Reduce directories, that is, ksh(1) canonical form+ resolveEnv2 env = env{operands = map reduceFilePath (operands env)}++{- |+'runWith' this environment. 'runWith' is the interface between the command+line options plus operands and the real work. 'runWith' is 'backstop'.+-}+runWith :: Environment -> IO ()+runWith = backstop
+ src/Manual.hs view
@@ -0,0 +1,272 @@+module Manual(putManual) where++import System.Exit (exitWith)+import Utils (putOrPageStrLn)++-- | Display the internal manual.++putManual :: IO ()+putManual = putOrPageStrLn internalManual >>= exitWith++-- | Internal manual. The definitive source of the internal manual is+-- the description section of the module Main.++internalManual :: String+internalManual =+ "backstop(1) User Commands backstop(1)\n"+++ "\n"+++ "NAME\n"+++ " backstop - Backstop a target directory by source directories\n"+++ "\n"+++ "SYNOPSIS\n"+++ " backstop [-nprt] [-a|-d] trgdir srcdir [srcdir ...]\n"+++ " backstop -h\n"+++ " backstop -l\n"+++ " backstop -m\n"+++ " backstop -v\n"+++ " backstop -y\n"+++ "\n"+++ "AVAILABILITY\n"+++ " Marcus D. Gabriel (c)1999-2017. All rights reserved.\n"+++ "\n"+++ " marcus@gabriel.name\n"+++ "\n"+++ " License terms: GNU GPL version 3 or later (backstop -l)\n"+++ "\n"+++ "DESCRIPTION\n"+++ " Backstop a target directory by source directories thereby\n"+++ " creating a backing chain using relative symbolic links by default\n"+++ " or absolute symbolic links by option. If more than one source\n"+++ " directory is given, backstop the target directory with each\n"+++ " source directory in turn starting from left to right on the\n"+++ " command line.\n"+++ "\n"+++ " Intuitively, backstop fills in the missing objects or holes that\n"+++ " exist in the target directory relative to the source directories\n"+++ " thereby creating a merged view of the target and source\n"+++ " directories.\n"+++ "\n"+++ " De-backstop a target directory by its source directories. In\n"+++ " this case, the source directories no longer need to exist. If\n"+++ " more than one source directory is given, de-backstop the target\n"+++ " directory by the source directories.\n"+++ "\n"+++ " Symbolic links are never followed. However, the target and\n"+++ " source directories are canonicalized (realpath(3)) internally by\n"+++ " the command backstop before backstopping and de-backstoppoing.\n"+++ "\n"+++ " By default no output is displayed except possibly to STDERR.\n"+++ "\n"+++ "ALGORITHM\n"+++ " There must be at least two arguments or operands. The first\n"+++ " operand is the target directory, and the second operand and\n"+++ " beyond are source directories. The target and source directory\n"+++ " must be parallel directories, that is, neither canonicalized\n"+++ " (realpath(3)) directory path may be a sub-directory of the other.\n"+++ " If the above is not true, a usage error occurs.\n"+++ "\n"+++ " Nevertheless, pathnames are internally in reduced form such that\n"+++ " symbolic link names are treated literally when finding directory\n"+++ " names. See \"cd -L\" of ksh(1). In other words, components in the\n"+++ " pathname that are not directories but symbolic links to\n"+++ " directories are not resolved to their corresponding directories.\n"+++ "\n"+++ " A list of objects or names is collected under the root of the\n"+++ " source directory excluding the directory dot (.) and the\n"+++ " directory double-dot (..). If the list is empty, the algorithm\n"+++ " is done, otherwise the objects divide into two classes, objects\n"+++ " that are not directories and objects that are directories. There\n"+++ " are five possibilities:\n"+++ "\n"+++ " 1. The object is either dot (.) or double-dot (..) whereupon no\n"+++ " action is taken.\n"+++ "\n"+++ " 2. If an object of the same name as the name of the object under\n"+++ " the root of the source directory does not exists under the\n"+++ " root of the target directory, then a symbolic link, relative\n"+++ " or absolute as required, is created under the root of the\n"+++ " target directory to the object under the root of the source\n"+++ " directory. If populating (-p) and the object under the root\n"+++ " of the source directory is a directory, then a sub-directory\n"+++ " is created instead.\n"+++ "\n"+++ " 3. If an object of the same name as the name of the object under\n"+++ " the root of the source directory does exists under the root of\n"+++ " the target directory and is a file, no action is taken,\n"+++ " regardless of whether or not the object under the root of the\n"+++ " source directory is a file or a directory.\n"+++ "\n"+++ " 4. If an object of the same name as the name of the object under\n"+++ " the root of the source directory does exists under the root of\n"+++ " the target directory and is a directory, and if the object of\n"+++ " the same name under the root of the source directory is a\n"+++ " file, no action is taken.\n"+++ "\n"+++ " 5. If an object of the same name as the name of the object under\n"+++ " the root of the source directory does exists under the root of\n"+++ " the target directory and is a directory, and if the object of\n"+++ " the same name under the root of the source directory is also a\n"+++ " directory, then recursion occurs with the objects of the same\n"+++ " name under the roots of the target and source directories as\n"+++ " new root target and source directories, respectively.\n"+++ "\n"+++ " When de-backstopping a target directory by source directories,\n"+++ " the sources no longer need to exist. Symbolic links under the\n"+++ " target are removed if and only if they point to a pahtname under\n"+++ " one of the source directories. This can be determined even if\n"+++ " the source directory no longer exists because symbolic links\n"+++ " within directory pathnames are taken literally. See \"cd -L\" of\n"+++ " ksh(1).\n"+++ "\n"+++ " When de-populating while de-backstopping (-pd), a directory is\n"+++ " removed if all objects within the directory are symbolic links\n"+++ " that have been remove while de-backstopping. An empty directory\n"+++ " is removed if and only if there exists a corresponding directory\n"+++ " path under one of the source directories as under the target\n"+++ " directory. This can only be determined if the source directory\n"+++ " and correponding sub-directory still exist. If not, then no\n"+++ " action is taken.\n"+++ "\n"+++ "OPTIONS\n"+++ " The following options are supported:\n"+++ "\n"+++ " -a Create symbolic links which are absolute paths.\n"+++ "\n"+++ " -d De-backstop the target directory by its source directories.\n"+++ " The -a option has no affect on the -d option.\n"+++ "\n"+++ " -h Display a short command summary.\n"+++ "\n"+++ " -l Display the backstop license terms.\n"+++ "\n"+++ " -m Display this internal manual page.\n"+++ "\n"+++ " -n Take no action but trace possible program execution. The -n\n"+++ " option implies the -t option.\n"+++ "\n"+++ " -p Populate the target by making equivalent sub-directories of\n"+++ " the source sub-directories instead of symbolic links for these\n"+++ " sub-directories that point back into the sources. For\n"+++ " example, if the target directory is empty, then for a set of\n"+++ " source directories, from left to right on the command line,\n"+++ " this creates a combined directory structure of the sources\n"+++ " under the target directory in which all non-directories are\n"+++ " symbolic links pointing back into the source directories.\n"+++ " This is similar to the lndir(1) command of the X consortium.\n"+++ "\n"+++ " With the -d option, all sub-directories emptied of symbolic\n"+++ " links under the target directory are removed, and all empty\n"+++ " directories are removed if and only if the correspoding\n"+++ " sub-directory under the source directory exists.\n"+++ "\n"+++ " -r Report the number of symbolic links and directories created,\n"+++ " the number of calls and maximum depth of backstop, the\n"+++ " maximum breadth observed by backstop, and the number of non-\n"+++ " fatal errors encountered. With the -d option, show the\n"+++ " number of symbolic links and directories removed.\n"+++ "\n"+++ " -t Show the trace of program execution. The output is a list\n"+++ " of executable commands.\n"+++ "\n"+++ " -v The version of backstop.\n"+++ "\n"+++ " -y A synopsis of the internal manual page.\n"+++ "\n"+++ "OPERANDS\n"+++ " trgdir\n"+++ " The directory that will be backed by other directories. The\n"+++ " target directory can be backed by multiple source directories\n"+++ " where each source directory could be backed by yet another\n"+++ " directory or multiple directories thereby creating an\n"+++ " extensible backing chain.\n"+++ "\n"+++ " srcdir\n"+++ " The directory which backs a target directory. The source\n"+++ " directory can be backed by multiple additional directories\n"+++ " where each additional directory could be backed by yet another\n"+++ " directory or multiple directories thereby creating an\n"+++ " extensible backing chain.\n"+++ "\n"+++ "USAGE NOTES\n"+++ " Evolved with ghc 6.10, 6.12, 7.0, 7.4, 7.10, 8.0.2, and 8.4.1.\n"+++ " Tested with 8.4.1.\n"+++ "\n"+++ "EXAMPLES\n"+++ " To display a summary of usage, use\n"+++ "\n"+++ " backstop -h\n"+++ "\n"+++ " To display a synopsis of this internal manual page, use\n"+++ "\n"+++ " backstop -y\n"+++ "\n"+++ " To display this internal manual page, use\n"+++ "\n"+++ " backstop -m\n"+++ "\n"+++ " To trace program execution, use\n"+++ "\n"+++ " backstop -t /export/install/sparc/devlopment/modules \\\n"+++ " /export/install/sparc/modules\n"+++ "\n"+++ " To trace program execution taking no action, use\n"+++ "\n"+++ " backstop -n /export/install/sparc/devlopment/modules \\\n"+++ " /export/install/sparc/modules\n"+++ "\n"+++ " To back /export/install/sparc/devlopment/modules with\n"+++ " /export/install/sparc/modules using relative symbolic links, use\n"+++ "\n"+++ " backstop /export/install/sparc/devlopment/modules \\\n"+++ " /export/install/sparc/modules\n"+++ "\n"+++ " To back /export/install/sparc/devlopment/modules with\n"+++ " /export/install/sparc/modules using absolute symbolic links, use\n"+++ "\n"+++ " backstop -a /export/install/sparc/devlopment/modules \\\n"+++ " /export/install/sparc/modules\n"+++ "\n"+++ " To stop backing /export/install/sparc/devlopment/modules with\n"+++ " /export/install/sparc/modules, use\n"+++ "\n"+++ " backstop -d /export/install/sparc/devlopment/modules \\\n"+++ " /export/install/sparc/modules\n"+++ "\n"+++ "ENVIRONMENT VARIABLES\n"+++ " PAGER Page the internal manual page or license terms\n"+++ " using \"${PAGER}\", otherwise print it.\n"+++ "\n"+++ "EXIT STATUS\n"+++ " An exit status of 0 is returned if successful, otherwise non-zero\n"+++ " is returned. The following error exit codes are used by\n"+++ " backstop:\n"+++ "\n"+++ " EXIT CODE MEANING\n"+++ " 251 Less than two operands.\n"+++ " 252 Not a directory, that is, trgdir or one or more\n"+++ " of the srcdir are not a directory.\n"+++ " 253 Not parallel directories, that is, a srcdir is\n"+++ " a sub-directory of trgdir or vice versa, or one\n"+++ " of the srcdir is a sub-directory of another\n"+++ " srcdir.\n"+++ " 254 Not yet implemented.\n"+++ " 255 Non-fatal errors occurred. Error messages are\n"+++ " sent to STDERR for each non-fatal error that\n"+++ " occurred with return code equal to the number of\n"+++ " non-falal errors if less than 251, otherwise the\n"+++ " return code is 255, that is, \"infinity\".\n"+++ "\n"+++ "FILES\n"+++ " N/A.\n"+++ "\n"+++ "SEE ALSO\n"+++ " ln(1), mkdir(1), rm(1), rmdir(1), ksh(1), lndir(1), realpath(3)\n"+++ "\n"+++ " \"Source Control to Project Control: Applying RCS and SCCS\" by Don\n"+++ " Bolinger and Tan Bronson. ISBN 1-56592-117-8.\n"+++ "\n"+++ "NOTES\n"+++ " Please send bug reports to marcus@gabriel.name.\n"+++ "\n"+++ "BUGS\n"+++ " No known bugs to date.\n"
+ src/Utils.hs view
@@ -0,0 +1,266 @@+module Utils (pairs+ , unpairs+ , root+ , dot+ , dotdot+ , reduceFilePath+ , absoluteLink+ , relativeLink+ , compElems+ , subdirectories+ , subdirectory+ , aDirectory+ , aSymbolicLink+ , anObject+ , putOrPageStrLn+ )+where++import Control.Exception (IOException, try)+import Control.Monad (unless)+import Data.List (nub,intersect,isPrefixOf,tails,foldl')+import Data.Maybe (fromJust,isNothing)+import System.Environment (getEnvironment)+import System.Exit (ExitCode(..))+import System.FilePath (pathSeparator,joinPath,(</>),isAbsolute,splitDirectories)+import System.IO (hClose,hFlush,hPutStr)+import System.Posix.Files (getSymbolicLinkStatus,isSymbolicLink,isDirectory)+import System.Process (waitForProcess,createProcess,shell,StdStream(..),CreateProcess(..))+++-- Section 0: exported items---------------------------------------------------------++-- | 'root' = @[pathSeparator]@+root :: FilePath+root = [pathSeparator]++-- | 'dot' = \".\"+dot :: FilePath+dot = "."++-- | 'dotdot' = \"..\"+dotdot :: FilePath+dotdot = ".."++-- | Given a list @[a]@, 'pairs' returns the list of all pairs+-- @[(a,a)]@ of @[a]@ progressing from the head to tail of @[a]@. For+-- example,+-- +-- > pairs [x1,x2,x3,x4]+-- > == [(x1,x2),(x1,x3),(x1,x4),(x2,x3),(x2,x4),(x3,x4)]+--+-- Note that+--+-- > pairs [] == []+-- > pairs (x:[]) == []++pairs :: [a] -> [(a,a)]+pairs [] = []+pairs [x] = []+pairs xs =+ let pair_ x0 = map (\x1 -> (x0,x1))+ xss = init $ init $ tails xs+ in concatMap (\xs -> pair_ (head xs) (tail xs)) xss++-- | For @length l /= 1@,+-- +-- > (unpairs . pairs) l == l+-- +-- is @True@.+--+-- > Number of elements Number of pairs+-- > ------------------ ---------------+-- > 0 => 0+-- > 1 => 0+-- > 2 => 1+-- > 3 => 3+-- > 4 => 6+-- > 5 => 10+-- > e => p = e(e-1)/2, e >= 0++unpairs :: Eq a => [(a,a)] -> [a]+unpairs ps+ | null ps = []+ | otherwise = fst (head ps) : foldr ((:).snd) [] (take (elements 0 (length ps) - 1) ps)+ where+ elements e p = if p == e*(e-1) `div` 2 then e else elements (e+1) p++-- | 'reduceFilePath' returns a pathname that is reduced to canonical+-- form equivalent to that of ksh(1), that is, symbolic link names are+-- treated literally when finding the directory name. See @cd -L@ of+-- ksh(1). Specifically, extraneous separators @(\"/\")@, dot+-- @(\".\")@, and double-dot @(\"..\")@ directories are removed.++reduceFilePath :: FilePath -> FilePath+reduceFilePath = joinPath . filePathComponents++-- | Given a pathname @wd@ representing a workng directory and two+-- pathnames @p1@ and @p2@, 'absoluteLink' returns the reduced+-- ('reduceFilePath') and absolute path to @p2@ to which @p1@ could point+-- as a symbolic link.+-- +-- If @wd@ is not an absolute path, it is assumed to be a relative+-- path that is relative to the root directory of the file system tree+-- and is made an absolute path.++absoluteLink :: FilePath -> FilePath -> FilePath -> FilePath+absoluteLink wd _ = reduceFilePath . ((pathSeparator:wd)</>)++-- | Given a pathname @wd@ representing a workng directory and two+-- pathnames @p1@ and @p2@, 'relativeLink' returns the reduced+-- ('reduceFilePath') and relative path from @p1@ to @p2@ to which+-- @p1@ could point as a symbolic link. Thus, @p1@ must not be the+-- root @(\"/\")@, dot @(\".\")@, nor double-dot @(\"..\")@+-- directories but of the form @\"\/SomePath\/SymLink\"@+-- +-- If @wd@ is not an absolute path, it is assumed to be a relative+-- path that is relative to the root directory of the file system tree+-- and is made an absolute path.++relativeLink :: FilePath -> FilePath -> FilePath -> FilePath+relativeLink wd p1 p2 =+ let wd_ = pathSeparator:wd+ ab p = if isAbsolute p then p else wd_ </> p+ (_, p1_, p2_) = decomposeFilePaths (ab p1) (ab p2)+ p1_s = map (const dotdot) $ splitDirectories p1_+ p1__ = (joinPath . (if null p1_s then id else tail)) p1_s+ p = p1__ </> p2_+ in if null p then dot else p++-- | 'compElems' compares elements of two lists and returns the list of+-- elements that are in both lists, unique to the first list, and+-- uniqued to the second list. Duplicates are 'nub'ed.++compElems :: Eq a => [a] -> [a] -> ([a], [a], [a])+compElems [] l2 = ([], [], nub l2)+compElems l1 [] = ([], nub l1, [])+compElems l1 l2 =+ let l1_ = nub l1+ l2_ = nub l2+ same = intersect l1_ l2_+ unique1 = filter (`notElem` same) l1_+ unique2 = filter (`notElem` same) l2_+ in (same, unique1, unique2)++-- | 'subdirectories' returns true if either the absolute pathname+-- @p1@ or the absolute pathname @p2@ is a sub-directory or sub-path+-- of the other.++subdirectories :: FilePath -> FilePath -> Bool+subdirectories p1 p2 = subdirectory p1 p2 || subdirectory p2 p1++-- | 'subdirectory' returns true if the absolute pathname @p1@ is a+-- subdirectory of the absolute pathname @p2@ as in+-- +-- > p1 `subdirectory` p2+-- +-- otherwise false.++subdirectory :: FilePath -> FilePath -> Bool+subdirectory p1 p2 =+ let x = filePathComponents p1+ y = filePathComponents p2+ in isPrefixOf y x++-- | 'aDirectory' returns true if @p@ is not a symbolic link+-- and is a directory, otherwise false.++aDirectory :: FilePath -> IO Bool+aDirectory =+ fmap (either (const False :: IOException -> Bool) isDirectory) . try . getSymbolicLinkStatus++-- | 'aSymbolicLink' returns true if @p@ is a symbolic link, otherwise+-- false.++aSymbolicLink :: FilePath -> IO Bool+aSymbolicLink =+ fmap (either (const False :: IOException -> Bool) isSymbolicLink) . try . getSymbolicLinkStatus++-- | 'anObject' returns true if @p@ is an object in the filesystem,+-- otherwise false. Symbolic links are not deferenced.++anObject :: FilePath -> IO Bool+anObject =+ fmap (either (const False :: IOException -> Bool) (const True)) . try . getSymbolicLinkStatus+++-- | Put a string or page it if the environmental variable PAGER is set.++putOrPageStrLn :: String -> IO ExitCode+putOrPageStrLn str+ | null str = return ExitSuccess+ | otherwise =+ do pager <- fmap (lookup "PAGER") getEnvironment+ if isNothing pager+ then putStrLn str >> return ExitSuccess+ else do (inh, _, _, pid) <- createProcess (shell $ fromJust pager){std_in = CreatePipe}+ unless (isNothing inh) $ do hPutStr (fromJust inh) str+ hFlush (fromJust inh)+ hClose (fromJust inh)+ waitForProcess pid+++-- Section 1 ------------------------------------------------------------------------++-- | Given two abosulte pathnames @p1@ and @p2@, 'decomposeFilePaths'+-- returns the common prefix to @p1@ and @p2@ plus the remainders of+-- @p1@ and @p2@, otherwise null plus @p1@ and @p2@.+decomposeFilePaths :: FilePath -> FilePath -> (FilePath, FilePath, FilePath)+decomposeFilePaths p1 p2+ | null p1 = ([], p1, p2)+ | null p2 = ([], p1, p2)+ | otherwise =+ let p1s = filePathComponents p1+ p2s = filePathComponents p2+ (pxs_, p1s_, p2s_) = decomposeFilePaths_ ([], p1s, p2s)+ decomposeFilePaths_ (pxs, [], p2s) = (pxs, [], p2s)+ decomposeFilePaths_ (pxs, p1s, []) = (pxs, p1s, [])+ decomposeFilePaths_ (pxs, p1s, p2s) =+ let p1h = head p1s+ p2h = head p2s+ p1t = tail p1s+ p2t = tail p2s+ in if p1h == p2h+ then decomposeFilePaths_ (pxs++[p1h], p1t, p2t)+ else (pxs, p1s, p2s)+ in (joinPath pxs_, joinPath p1s_, joinPath p2s_)+++-- Section 2 ------------------------------------------------------------------------++-- | 'filePathComponents' returns pathname components that are reduced+-- to canonical form equivalent to that of ksh(1), that is, symbolic+-- link names are treated literally when finding the directory name.+-- See @cd -L@ of ksh(1). Specifically, extraneous separators+-- @(\"/\")@, dot @(\".\")@, and double-dot @(\"..\")@ directories are+-- removed.++filePathComponents :: FilePath -> [FilePath]+filePathComponents p+ | null p = [dot]+ | otherwise = let c = head p+ cs = tail p+ in reverse $ snd $ foldl accumulate+ (if c == pathSeparator then ([],[root]) else ([c],[dot]))+ (cs++root)+ where+ accumulate :: (String,[String]) -> Char -> (String,[String])+ accumulate (cs, css) c =+ if c == pathSeparator+ then ([],(if null cs then id else cons cs) css)+ else (cs++[c],css)+ cons :: String -> [String] -> [String]+ cons cs css+ | cs == dot = css+ | css == [dot] = [cs]+ | cs /= dotdot || null css = cs : css+ | otherwise =+ let hd = head css+ tl = tail css+ in if hd == root+ then css+ else if hd == dotdot+ then cs : css+ else if null tl+ then [dot]+ else tl
+ tests/RunTests.hs view
@@ -0,0 +1,641 @@+module Main(main) where++import Control.Monad (unless)+import Data.List (sort,nub,intersect)+import System.Exit (exitWith,ExitCode(..))+import System.IO (hPutStrLn,hFlush,stdout,stderr)+import System.FilePath ((</>),pathSeparator,isAbsolute,isRelative,joinPath)+import System.Process (runCommand,waitForProcess)+import Test.HUnit hiding (Testable)+import Test.QuickCheck (Testable(..),Property(..),(==>),Result(..),quickCheckResult)+import Utils (putOrPageStrLn,anObject,aSymbolicLink,aDirectory,subdirectories+ ,subdirectory,root,reduceFilePath,compElems,pairs,unpairs,dot,dotdot+ ,relativeLink,absoluteLink)+++-- Section 0 ------------------------------------------------------------------------++main :: IO ()+main = do putMessage "Unit test reduceFilePath:"+ runTestTT checks4reduceFilePath >>= checkCounts++ putMessage "Property test reduceFilePath:"+ mapM_ runTest props4reduceFilePath+ mapM_ runTest props4reduceFilePath_++ putMessage "Unit test absoluteLink:"+ runTestTT checks4absoluteLink >>= checkCounts++ putMessage "Property test absoluteLink:"+ mapM_ runTest props4absoluteLink++ putMessage "Unit test relativeLink:"+ runTestTT checks4relativeLink >>= checkCounts++ putMessage "Property test relativeLink:"+ mapM_ runTest props4relativeLink++ putMessage "Unit test pairs:"+ runTestTT checks4pairs >>= checkCounts++ putMessage "Unit test unpairs . pairs == id:"+ runTestTT checks4unpairsPairs >>= checkCounts++ putMessage "Property test unpairs . pairs == id:"+ mapM_ runTest props4unpairsPairs++ putMessage "Unit test compElems:"+ runTestTT check4compElems >>= checkCounts++ putMessage "Property test compElems:"+ mapM_ runTest props4check4compElems++ putMessage "Unit test subdirectory:"+ runTestTT checks4subdirectory >>= checkCounts++ putMessage "Unit test subdirectories:"+ runTestTT checks4subdirectories >>= checkCounts++ putMessage "Property test subdirectory and subdirectories:"+ mapM_ runTest props4Subdirectories++ putMessage "Unit test aDirectory:"+ runTestTT checks4aDirectory >>= checkCounts++ putMessage "Unit test aSymbolicLink:"+ runTestTT checks4aSymbolicLink >>= checkCounts++ putMessage "Unit test anObject:"+ runTestTT checks4anObject >>= checkCounts++ putMessage "Unit test putOrPageStrLn:"+ runTestTT checks4putOrPageStrLn >>= checkCounts++ putMessage "Running black box tests:"+ runTests >>= exitWith++checkCounts :: Counts -> IO ()+checkCounts cnts = let errs = errors cnts + failures cnts+ in if errs > 0+ then exitWith $ ExitFailure (if errs < 256 then errs else 255)+ else putStrLn ""++runTest :: Testable t => (String, t) -> IO ()+runTest (s, t) = do putStrLn s+ verify t+ putStrLn ""++putMessage :: String -> IO ()+putMessage s = let l = length s+ in do putStrLn s+ (putStrLn . replicate l) '='+ hFlush stdout+++-- Section 1 ------------------------------------------------------------------------++checks4reduceFilePath :: Test+checks4reduceFilePath =+ let checkReduceFilePath p1 p2+ = TestCase (assertEqual "reduceFilePath" p2 (reduceFilePath p1))+ in TestList+ [+ -- The special case of null arguments+ checkReduceFilePath "" "."++ -- The special case of dot+ , checkReduceFilePath "." "."++ -- The special case of double dot+ , checkReduceFilePath ".." ".."++ -- Only slashes+ , checkReduceFilePath "/" "/"+ , checkReduceFilePath "//" "/"+ , checkReduceFilePath "///" "/"++ -- Only dots and slashes+ , checkReduceFilePath "./" "."+ , checkReduceFilePath ".//" "."+ , checkReduceFilePath ".///" "."+ , checkReduceFilePath "./." "."+ , checkReduceFilePath ".//." "."+ , checkReduceFilePath ".///." "."+ , checkReduceFilePath "././" "."+ , checkReduceFilePath ".//./././///." "."+ , checkReduceFilePath "././././././././" "."++ -- Only slashes and dots+ , checkReduceFilePath "/." "/"+ , checkReduceFilePath "//." "/"+ , checkReduceFilePath "/./" "/"+ , checkReduceFilePath "///.///" "/"+ , checkReduceFilePath "/./././." "/"+ , checkReduceFilePath "//.//.//.//." "/"++ -- Only slashes and double dots+ , checkReduceFilePath "/.." "/"+ , checkReduceFilePath "/../" "/"+ , checkReduceFilePath "///..///" "/"+ , checkReduceFilePath "/../../../../" "/"++ -- Only double dots and slashes+ , checkReduceFilePath "../" ".."+ , checkReduceFilePath "..///" ".."+ , checkReduceFilePath "..///.." "../.."+ , checkReduceFilePath "../../../../" "../../../.."+ , checkReduceFilePath "..///..///..///..///" "../../../.."++ -- Absolute paths with only slahses+ , checkReduceFilePath "/a" "/a"+ , checkReduceFilePath "/a/b" "/a/b"+ , checkReduceFilePath "//a" "/a"+ , checkReduceFilePath "//a//b" "/a/b"+ , checkReduceFilePath "//a///" "/a"+ , checkReduceFilePath "//a//b///" "/a/b"+ + -- Relative paths with only slahses+ , checkReduceFilePath "a" "a"+ , checkReduceFilePath "a/b" "a/b"+ , checkReduceFilePath "a" "a"+ , checkReduceFilePath "a//b" "a/b"+ , checkReduceFilePath "a///" "a"+ , checkReduceFilePath "a//b///" "a/b"++ -- Absolute paths with dots+ , checkReduceFilePath "/a/." "/a"+ , checkReduceFilePath "/a/./." "/a"+ , checkReduceFilePath "/./a" "/a"+ , checkReduceFilePath "/./a/./." "/a"++ -- Relative paths with dots+ , checkReduceFilePath "a/." "a"+ , checkReduceFilePath "a/./." "a"+ , checkReduceFilePath "./a" "a"+ , checkReduceFilePath "./a/./." "a"++ -- Absolute paths with double dots+ , checkReduceFilePath "/.." "/"+ , checkReduceFilePath "/a/.." "/"+ , checkReduceFilePath "/a/b/.." "/a"+ , checkReduceFilePath "/a/b/c/.." "/a/b"+ , checkReduceFilePath "/a/../b" "/b"+ , checkReduceFilePath "/a/b/../c" "/a/c"+ , checkReduceFilePath "/a/b/c/../.." "/a"+ , checkReduceFilePath "/a/b/c/../../.." "/"+ , checkReduceFilePath "/a/b/c/../../../.." "/"+ , checkReduceFilePath "/a/b/c/../x/y/../z" "/a/b/x/z"+ + -- Relative paths with double dots+ , checkReduceFilePath "a/.." "."+ , checkReduceFilePath "a/b/.." "a"+ , checkReduceFilePath "a/b/c/.." "a/b"+ , checkReduceFilePath "a/../b" "b"+ , checkReduceFilePath "a/b/../c" "a/c"+ , checkReduceFilePath "a/b/c/../.." "a"+ , checkReduceFilePath "a/b/c/../../.." "."+ , checkReduceFilePath "a/b/c/../../../.." ".."+ , checkReduceFilePath "a/b/c/../../../../.." "../.."+ , checkReduceFilePath "a/b/c/../x/y/../z" "a/b/x/z"++ -- General abosulte paths+ , checkReduceFilePath "/a/b/./x/y/z/../." "/a/b/x/y"+ , checkReduceFilePath "/./a/.." "/"+ , checkReduceFilePath "/a/./b/c/../x/y/./.." "/a/b/x"+ , checkReduceFilePath "/a/b/c/d/e/f/g/h/../../../../../e/f/g/h/i" "/a/b/c/e/f/g/h/i"++ -- General reltative paths+ , checkReduceFilePath "a/b/./x/y/z/../." "a/b/x/y"+ , checkReduceFilePath "./a/.." "."+ , checkReduceFilePath "a/./b/c/../x/y/./.." "a/b/x"+ , checkReduceFilePath "./../../../a/b/c/./x/y/z" "../../../a/b/c/x/y/z"+ , checkReduceFilePath "a/b/c/d/e/f/g/h/../../../../../e/f/g/h/i" "a/b/c/e/f/g/h/i"+ ]+++-- Section 2 ------------------------------------------------------------------------++props4reduceFilePath :: [(String, FilePath -> Property)]+props4reduceFilePath = [ ("propReduceFilePathIdempotent", propReduceFilePathIdempotent)+ , ("propReduceFilePathStaysAbsolute", propReduceFilePathStaysAbsolute)+ , ("propReduceFilePathStaysRelative", propReduceFilePathStaysRelative)+ ]++props4reduceFilePath_ :: [(String, FilePath -> FilePath -> Property)]+props4reduceFilePath_ = [ ("propReduceFilePathAssociativity", propReduceFilePathAssociativity)+ ]++propReduceFilePathIdempotent :: FilePath -> Property+propReduceFilePathIdempotent p =+ property $ (reduceFilePath . reduceFilePath) p == reduceFilePath p++propReduceFilePathStaysAbsolute :: FilePath -> Property+propReduceFilePathStaysAbsolute p =+ let p' = root </> p+ in property $ (isAbsolute . reduceFilePath) p' == isAbsolute p'++propReduceFilePathStaysRelative :: FilePath -> Property+propReduceFilePathStaysRelative p =+ (not (null p) && (head p /= pathSeparator)) ==>+ (isRelative . reduceFilePath) p == isRelative p++propReduceFilePathAssociativity :: FilePath -> FilePath -> Property+propReduceFilePathAssociativity p1 p2 =+ property (reduceFilePath (p1 </> p2) == reduceFilePath (reduceFilePath p1 </> reduceFilePath p2))+++-- Section 3 ------------------------------------------------------------------------++checks4absoluteLink :: Test+checks4absoluteLink =+ let+ checkAbsoluteLink wd p1 p2 p =+ TestCase (assertEqual "absoluteLink" p (absoluteLink wd p1 p2))+ in TestList+ [ checkAbsoluteLink "" "" "" root+ , checkAbsoluteLink "" "" "." root+ , checkAbsoluteLink "" "" ".." root+ , checkAbsoluteLink "" "X" "" root+ , checkAbsoluteLink "" "X" "." root+ , checkAbsoluteLink "" "X" ".." root+ , checkAbsoluteLink root "" "" root+ , checkAbsoluteLink root "" "." root+ , checkAbsoluteLink root "" ".." root+ , checkAbsoluteLink root "X" "" root+ , checkAbsoluteLink root "X" "." root+ , checkAbsoluteLink root "X" ".." root+ , checkAbsoluteLink "/xx/yy/zz" "" "" "/xx/yy/zz"+ , checkAbsoluteLink "/xx/yy/zz" "" "." "/xx/yy/zz"+ , checkAbsoluteLink "/xx/yy/zz" "" ".." "/xx/yy"+ , checkAbsoluteLink "/xx/yy/zz" "X" "" "/xx/yy/zz"+ , checkAbsoluteLink "/xx/yy/zz" "X" "." "/xx/yy/zz"+ , checkAbsoluteLink "/xx/yy/zz" "X" ".." "/xx/yy"+ , checkAbsoluteLink "xx/yy/zz" "" "" "/xx/yy/zz"+ , checkAbsoluteLink "xx/yy/zz" "" "." "/xx/yy/zz"+ , checkAbsoluteLink "xx/yy/zz" "" ".." "/xx/yy"+ , checkAbsoluteLink "xx/yy/zz" "X" "" "/xx/yy/zz"+ , checkAbsoluteLink "xx/yy/zz" "X" "." "/xx/yy/zz"+ , checkAbsoluteLink "xx/yy/zz" "X" ".." "/xx/yy"+ , checkAbsoluteLink "" "" "aa/bb/cc" "/aa/bb/cc"+ , checkAbsoluteLink "" "" "aa/bb/cc/." "/aa/bb/cc"+ , checkAbsoluteLink "" "" "aa/bb/cc/.." "/aa/bb"+ , checkAbsoluteLink "" "X" "aa/bb/cc/" "/aa/bb/cc"+ , checkAbsoluteLink "" "X" "aa/bb/cc/." "/aa/bb/cc"+ , checkAbsoluteLink "" "X" "aa/bb/cc/.." "/aa/bb"+ , checkAbsoluteLink root "" "aa/bb/cc/" "/aa/bb/cc"+ , checkAbsoluteLink root "" "aa/bb/cc/." "/aa/bb/cc"+ , checkAbsoluteLink root "" "aa/bb/cc/.." "/aa/bb"+ , checkAbsoluteLink root "X" "aa/bb/cc/" "/aa/bb/cc"+ , checkAbsoluteLink root "X" "aa/bb/cc/." "/aa/bb/cc"+ , checkAbsoluteLink root "X" "aa/bb/cc/.." "/aa/bb"+ , checkAbsoluteLink "/xx/yy/zz" "" "aa/bb/cc/" "/xx/yy/zz/aa/bb/cc"+ , checkAbsoluteLink "/xx/yy/zz" "" "aa/bb/cc/." "/xx/yy/zz/aa/bb/cc"+ , checkAbsoluteLink "/xx/yy/zz" "" "aa/bb/cc/.." "/xx/yy/zz/aa/bb"+ , checkAbsoluteLink "/xx/yy/zz" "X" "aa/bb/cc/" "/xx/yy/zz/aa/bb/cc"+ , checkAbsoluteLink "/xx/yy/zz" "X" "aa/bb/cc/." "/xx/yy/zz/aa/bb/cc"+ , checkAbsoluteLink "/xx/yy/zz" "X" "aa/bb/cc/.." "/xx/yy/zz/aa/bb"+ , checkAbsoluteLink "xx/yy/zz" "" "aa/bb/cc/" "/xx/yy/zz/aa/bb/cc"+ , checkAbsoluteLink "xx/yy/zz" "" "aa/bb/cc/." "/xx/yy/zz/aa/bb/cc"+ , checkAbsoluteLink "xx/yy/zz" "" "aa/bb/cc/.." "/xx/yy/zz/aa/bb"+ , checkAbsoluteLink "xx/yy/zz" "X" "aa/bb/cc/" "/xx/yy/zz/aa/bb/cc"+ , checkAbsoluteLink "xx/yy/zz" "X" "aa/bb/cc/." "/xx/yy/zz/aa/bb/cc"+ , checkAbsoluteLink "xx/yy/zz" "X" "aa/bb/cc/.." "/xx/yy/zz/aa/bb"+ ]+++-- Section 4 ------------------------------------------------------------------------++wd :: FilePath+wd = joinPath $ map show [0..9]++props4absoluteLink :: [(String, FilePath -> FilePath -> Property)]+props4absoluteLink = [ ("propAbsoluteLinkIdempotent root", propAbsoluteLinkIdempotent root)+ , ("propAbsoluteLinkIdempotent wd", propAbsoluteLinkIdempotent wd)+ , ("propAbsoluteLinkStaysAbsolute root", propAbsoluteLinkStaysAbsolute root)+ , ("propAbsoluteLinkStaysAbsolute wd", propAbsoluteLinkStaysAbsolute wd)+ , ("propAbsoluteLinkIsNotRelative root", propAbsoluteLinkIsNotRelative root)+ , ("propAbsoluteLinkIsNotRelative wd", propAbsoluteLinkIsNotRelative wd)+ ]++propAbsoluteLinkIdempotent :: FilePath -> FilePath -> FilePath -> Property+propAbsoluteLinkIdempotent wd p1 p2 =+ property $ (absoluteLink wd p1 . absoluteLink wd p1) p2 == absoluteLink wd p1 p2++propAbsoluteLinkStaysAbsolute :: FilePath -> FilePath -> FilePath -> Property+propAbsoluteLinkStaysAbsolute wd p1 =+ property . isAbsolute . absoluteLink wd p1++propAbsoluteLinkIsNotRelative :: FilePath -> FilePath -> FilePath -> Property+propAbsoluteLinkIsNotRelative wd p1 =+ property . not. isRelative . absoluteLink wd p1+++-- Section 5 ------------------------------------------------------------------------++checks4relativeLink :: Test+checks4relativeLink =+ let+ checkRelativeLink wd p1 p2 p =+ TestCase (assertEqual "relativeLink" p (relativeLink wd p1 p2))+ in TestList+ [ checkRelativeLink "" "" "" dot+ , checkRelativeLink "" "" "." dot+ , checkRelativeLink "" "" ".." dot+ , checkRelativeLink "" "X" "" dot+ , checkRelativeLink "" "X" "." dot+ , checkRelativeLink "" "X" ".." dot+ , checkRelativeLink root "" "" dot+ , checkRelativeLink root "" "." dot+ , checkRelativeLink root "" ".." dot+ , checkRelativeLink root "X" "" dot+ , checkRelativeLink root "X" "." dot+ , checkRelativeLink root "X" ".." dot+ , checkRelativeLink "/xx/yy/zz" "" "" dot+ , checkRelativeLink "/xx/yy/zz" "" "." dot+ , checkRelativeLink "/xx/yy/zz" "" ".." dot+ , checkRelativeLink "/xx/yy/zz" "X" "" dot+ , checkRelativeLink "/xx/yy/zz" "X" "." dot+ , checkRelativeLink "/xx/yy/zz" "X" ".." dotdot+ , checkRelativeLink "xx/yy/zz" "" "" dot+ , checkRelativeLink "xx/yy/zz" "" "." dot+ , checkRelativeLink "xx/yy/zz" "" ".." dot+ , checkRelativeLink "xx/yy/zz" "X" "" dot+ , checkRelativeLink "xx/yy/zz" "X" "." dot+ , checkRelativeLink "xx/yy/zz" "X" ".." dotdot+ , checkRelativeLink "" "" "aa/bb/cc" "aa/bb/cc"+ , checkRelativeLink "" "" "aa/bb/cc/." "aa/bb/cc"+ , checkRelativeLink "" "" "aa/bb/cc/.." "aa/bb"+ , checkRelativeLink "" "X" "aa/bb/cc/" "aa/bb/cc"+ , checkRelativeLink "" "X" "aa/bb/cc/." "aa/bb/cc"+ , checkRelativeLink "" "X" "aa/bb/cc/.." "aa/bb"+ , checkRelativeLink root "" "aa/bb/cc/" "aa/bb/cc"+ , checkRelativeLink root "" "aa/bb/cc/." "aa/bb/cc"+ , checkRelativeLink root "" "aa/bb/cc/.." "aa/bb"+ , checkRelativeLink root "X" "aa/bb/cc/" "aa/bb/cc"+ , checkRelativeLink root "X" "aa/bb/cc/." "aa/bb/cc"+ , checkRelativeLink root "X" "aa/bb/cc/.." "aa/bb"+ , checkRelativeLink "/xx/yy/zz" "" "aa/bb/cc/" "aa/bb/cc"+ , checkRelativeLink "/xx/yy/zz" "" "aa/bb/cc/." "aa/bb/cc"+ , checkRelativeLink "/xx/yy/zz" "" "aa/bb/cc/.." "aa/bb"+ , checkRelativeLink "/xx/yy/zz" "X" "aa/bb/cc/" "aa/bb/cc"+ , checkRelativeLink "/xx/yy/zz" "X" "aa/bb/cc/." "aa/bb/cc"+ , checkRelativeLink "/xx/yy/zz" "X" "aa/bb/cc/.." "aa/bb"+ , checkRelativeLink "xx/yy/zz" "" "aa/bb/cc/" "aa/bb/cc"+ , checkRelativeLink "xx/yy/zz" "" "aa/bb/cc/." "aa/bb/cc"+ , checkRelativeLink "xx/yy/zz" "" "aa/bb/cc/.." "aa/bb"+ , checkRelativeLink "xx/yy/zz" "X" "aa/bb/cc/" "aa/bb/cc"+ , checkRelativeLink "xx/yy/zz" "X" "aa/bb/cc/." "aa/bb/cc"+ , checkRelativeLink "xx/yy/zz" "X" "aa/bb/cc/.." "aa/bb"+ , checkRelativeLink "xx/yy/zz" "a" "a/bb/cc" "bb/cc"+ , checkRelativeLink "xx/yy" "a/b" "a/b/cc" "cc"+ ]+++-- Section 6 ------------------------------------------------------------------------++props4relativeLink :: [(String, FilePath -> FilePath -> Property)]+props4relativeLink = [ ("propRelativeLinkStaysRelative root", propRelativeLinkStaysRelative root)+ , ("propRelativeLinkStaysRelative wd", propRelativeLinkStaysRelative wd)+ , ("propRelativeLinkIsNotAbsolute root", propRelativeLinkIsNotAbsolute root)+ , ("propRelativeLinkIsNotAbsolute wd", propRelativeLinkIsNotAbsolute wd)+ , ("propSubRelativeLinkIsTarget root", propSubRelativeLinkIsTarget root)+ , ("propSubRelativeLinkIsTarget wd", propSubRelativeLinkIsTarget wd)+ ]++propRelativeLinkStaysRelative :: FilePath -> FilePath -> FilePath -> Property+propRelativeLinkStaysRelative wd p1 = property . isRelative . relativeLink wd p1++propRelativeLinkIsNotAbsolute :: FilePath -> FilePath -> FilePath -> Property+propRelativeLinkIsNotAbsolute wd p1 = property . not. isAbsolute . relativeLink wd p1++propSubRelativeLinkIsTarget :: FilePath -> FilePath -> FilePath -> Property+propSubRelativeLinkIsTarget wd p1 p2 =+ let rl = relativeLink wd (p1 </> "symlink") p2+ abs p = if isAbsolute p then p else (pathSeparator:wd) </> p+ in property (reduceFilePath (abs p2) == reduceFilePath (abs p1 </> rl))+++-- Section 7 ------------------------------------------------------------------------++checks4pairs :: Test+checks4pairs =+ let checkPairs xs ps = TestCase (assertEqual "pairs" ps (pairs xs))+ in TestList+ [+ -- Null and one element+ checkPairs [] ([] :: [(Int,Int)])+ , checkPairs [0] []++ -- One pair+ , checkPairs [0,0] [(0,0)]+ , checkPairs [0,1] [(0,1)]+ , checkPairs [1,0] [(1,0)]++ -- Three pairs+ , checkPairs [0,0,0] [(0,0),(0,0),(0,0)]+ , checkPairs [0,0,2] [(0,0),(0,2),(0,2)]+ , checkPairs [0,1,0] [(0,1),(0,0),(1,0)]+ , checkPairs [0,1,1] [(0,1),(0,1),(1,1)]+ , checkPairs [0,1,2] [(0,1),(0,2),(1,2)]+ , checkPairs [1,0,2] [(1,0),(1,2),(0,2)]+ , checkPairs [2,1,0] [(2,1),(2,0),(1,0)]+ , checkPairs [0,2,1] [(0,2),(0,1),(2,1)]+ ]+++-- Section 8 ------------------------------------------------------------------------++checks4unpairsPairs :: Test+checks4unpairsPairs =+ let l = [[],[0,0],[0,1],[1,0],[0,0,0],[0,0,2],[0,1,0],[0,1,1],[0,1,2],[1,0,2],[2,1,0],[0,2,1]]+ in TestCase (assertEqual "unpairs/pairs" l (map (unpairs.pairs) l))++props4unpairsPairs :: [(String, [Int] -> Property)]+props4unpairsPairs = [("propUnpairsPairsId", propUnpairsPairsId)]++propUnpairsPairsId :: [Int] -> Property+propUnpairsPairsId xs = length xs /= 1 ==> xs == (unpairs.pairs) xs+++-- Section 9 ------------------------------------------------------------------------++check4compElems :: Test+check4compElems =+ let checkCompElems xs ys ts = TestCase (assertEqual "compElems" ts (compElems xs ys))+ in TestList+ [ checkCompElems ([]::[Int]) [] ([],[],[])+ , checkCompElems [0..9] [] ([],[0..9],[])+ , checkCompElems [] [0..9] ([],[],[0..9])+ , checkCompElems [0..9] [0..9] ([0..9],[],[])+ , checkCompElems [0..9] [10..19] ([],[0..9],[10..19])+ , checkCompElems [0..9] [0..19] ([0..9],[],[10..19])+ , checkCompElems [0..19] [0..9] ([0..9],[10..19],[])+ , checkCompElems [0..19] [-9..9] ([0..9],[10..19],[-9..(-1)])+ ]++props4check4compElems :: [(String,[Int] -> [Int] -> Property)]+props4check4compElems = [("propCompElemsDisjoint",propCompElemsDisjoint)+ ,("propCompElemsComplete",propCompElemsComplete)+ ]++propCompElemsDisjoint :: [Int] -> [Int] -> Property+propCompElemsDisjoint xs ys = let (same, unique1, unique2) = compElems xs ys+ in property (+ null (same `intersect` unique1) &&+ null (same `intersect` unique2) &&+ null (unique1 `intersect` unique2)+ )++propCompElemsComplete :: [Int] -> [Int] -> Property+propCompElemsComplete xs ys = let (same, unique1, unique2) = compElems xs ys+ in property (+ sort (nub xs) == sort (same++unique1) &&+ sort (nub ys) == sort (same++unique2)+ )+++-- Section 10 -----------------------------------------------------------------------++checks4subdirectory :: Test+checks4subdirectory =+ let checkSubdirectory d1 d2 b = TestCase (assertEqual "subdirectory" b (d1 `subdirectory` d2))+ in TestList+ [ checkSubdirectory "/" "/" True+ , checkSubdirectory "/" "/." True+ , checkSubdirectory "/." "/" True+ , checkSubdirectory "/." "/." True+ , checkSubdirectory "/" "/.." True+ , checkSubdirectory "/.." "/" True+ , checkSubdirectory "/.." "/.." True+ , checkSubdirectory "/.." "/." True+ , checkSubdirectory "/." "/.." True+ , checkSubdirectory "/a/b/c" "/x/y/z" False+ , checkSubdirectory "/x/y/z" "/a/b/c" False+ , checkSubdirectory "/x/y/z" "/x/y/z" True+ , checkSubdirectory "/x/y/z" "/x/y" True+ , checkSubdirectory "/x/y" "/x/y/z" False+ ]++checks4subdirectories :: Test+checks4subdirectories =+ let checkSubdirectories d2 d1 b = TestCase (assertEqual "subdirectories" b (d2 `subdirectories` d1))+ in TestList+ [ checkSubdirectories "/" "/" True+ , checkSubdirectories "/" "/." True+ , checkSubdirectories "/." "/" True+ , checkSubdirectories "/." "/." True+ , checkSubdirectories "/" "/.." True+ , checkSubdirectories "/.." "/" True+ , checkSubdirectories "/.." "/.." True+ , checkSubdirectories "/.." "/." True+ , checkSubdirectories "/." "/.." True+ , checkSubdirectories "/a/b/c" "/x/y/z" False+ , checkSubdirectories "/x/y/z" "/a/b/c" False+ , checkSubdirectories "/x/y/z" "/x/y/z" True+ , checkSubdirectories "/x/y/z" "/x/y" True+ , checkSubdirectories "/x/y" "/x/y/z" True+ ]++props4Subdirectories :: [(String, FilePath -> FilePath -> Property)]+props4Subdirectories = [ ("propSubdirectory",propSubdirectory)+ , ("propSubdirectories",propSubdirectories)+ ]++propSubdirectory :: FilePath -> FilePath -> Property+propSubdirectory d1 d2 =+ let d1_ = root </> d1+ d2_ = root </> d2+ in property (+ if reduceFilePath d1_ == reduceFilePath d2_+ then d1_ `subdirectory` d2_+ else if d1_ `subdirectory` d2_+ then not (d2_ `subdirectory` d1_)+ else if d2_ `subdirectory` d1_+ then not (d1_ `subdirectory` d2_)+ else not (d1_ `subdirectory` d2_) && not (d2_ `subdirectory` d1_)+ )++propSubdirectories :: FilePath -> FilePath -> Property+propSubdirectories d1 d2 =+ let d1_ = root </> d1+ d2_ = root </> d2+ in property (+ (subdirectories d1_ d2_ && subdirectories d2_ d1_) ||+ (not (subdirectories d1_ d2_) && not (subdirectories d2_ d1_))+ )+++-- Section 11 -----------------------------------------------------------------------++checks4aDirectory :: Test+checks4aDirectory =+ let check4aDirectory p expected = + TestCase (aDirectory p >>= assertBool "aDirectory" . (expected==))+ in TestList+ [ check4aDirectory "/" True+ , check4aDirectory "." True+ , check4aDirectory ".." True+ , check4aDirectory "/etc/passwd" False+ , check4aDirectory "/var/run" False+ , check4aDirectory "RaNdOmJuNk" False+ ]++checks4aSymbolicLink :: Test+checks4aSymbolicLink =+ let check4aSymbolicLink p expected = + TestCase (aSymbolicLink p >>= assertBool "aSymbolicLink" . (expected==))+ in TestList+ [ check4aSymbolicLink "/" False+ , check4aSymbolicLink "." False+ , check4aSymbolicLink ".." False+ , check4aSymbolicLink "/etc/passwd" False+ , check4aSymbolicLink "/var/run" True+ , check4aSymbolicLink "RaNdOmJuNk" False+ ]++checks4anObject :: Test+checks4anObject =+ let check4anObject p expected = + TestCase (anObject p >>= assertBool "anObject" . (expected==))+ in TestList+ [ check4anObject "/" True+ , check4anObject "." True+ , check4anObject ".." True+ , check4anObject "/etc/passwd" True+ , check4anObject "RaNdOmJuNk" False+ , check4anObject "/cdrom" True+ ]+++-- Section 12 -----------------------------------------------------------------------++checks4putOrPageStrLn :: Test+checks4putOrPageStrLn =+ let check4putOrPageStrLn s =+ TestCase $ assert (putOrPageStrLn s >>= \e -> unless (e == ExitSuccess) $ exitWith e)+ in TestList+ [ check4putOrPageStrLn ""+ , check4putOrPageStrLn "."+ ]+++-- Section 13 ------------------------------------------------------------------------++runTests :: IO ExitCode+runTests =+ runCommand "./tests/run-tests.sh dist*/build/*/ghc-*/backstop-*/x/backstop/build/backstop/backstop"+ >>= waitForProcess++-- Section Last ---------------------------------------------------------------------++verify :: Testable a => a -> IO ()+verify t =+ do result <- quickCheckResult t+ case result of+ Success{} -> return ()+ GaveUp ntest _ _ _ _ _ -> do hPutStrLn stderr ("Gave up after "++show ntest++" tests")+ exitWith (ExitFailure (if ntest < 255 then ntest else 255))+ Failure _ _ _ _ _ _ _ reason _ _ _ _ _ -> do hPutStrLn stderr ("Failure: "++reason)+ exitWith (ExitFailure 255)+ _ -> do hPutStrLn stderr "Not a success"+ exitWith (ExitFailure 255)