@@ -1,81 +1,42 @@
11{-# LANGUAGE TemplateHaskell #-}
22{-# LANGUAGE CPP #-}
3−{-# LANGUAGE OverloadedStrings #-}
4−-- | This module uses template Haskell. Following is a simplified explanation of usage for those unfamiliar with calling Template Haskell functions.
5−--
6−-- The function @embedFile@ in this modules embeds a file into the executable
7−-- that you can use it at runtime. A file is represented as a @ByteString@.
8−-- However, as you can see below, the type signature indicates a value of type
9−-- @Q Exp@ will be returned. In order to convert this into a @ByteString@, you
10−-- must use Template Haskell syntax, e.g.:
11−--
12−-- > $(embedFile "myfile.txt")
13−--
14−-- This expression will have type @ByteString@. Be certain to enable the
15−-- TemplateHaskell language extension, usually by adding the following to the
16−-- top of your module:
17−--
18−-- > {-# LANGUAGE TemplateHaskell #-}
193module Data.FileEmbed
204 ( -- * Embed at compile time
215 embedFile
22− , embedFileIfExists
23− , embedOneFileOf
246 , embedDir
25− , embedDirListing
267 , getDir
27− -- * Embed as a IsString
28− , embedStringFile
29− , embedOneStringFileOf
308 -- * Inject into an executable
31− -- $inject
329#if MIN_VERSION_template_haskell(2,5,0)
3310 , dummySpace
34− , dummySpaceWith
3511#endif
3612 , inject
3713 , injectFile
38− , injectWith
39− , injectFileWith
40− -- * Relative path manipulation
41− , makeRelativeToProject
42− , makeRelativeToLocationPredicate
43− -- * Internal
44− , stringToBs
45− , bsToExp
46− , strToExp
4714 ) where
4815
4916import Language.Haskell.TH.Syntax
50− ( Exp (AppE, ListE, LitE, TupE, SigE, VarE)
51− , Lit (..)
17+ ( runQ
18+ , Exp (AppE, ListE, LitE, TupE)
19+#if MIN_VERSION_template_haskell(2,5,0)
20+ , Lit (StringL, StringPrimL, IntegerL)
21+#else
22+ , Lit (StringL, IntegerL)
23+#endif
5224 , Q
5325 , runIO
54− , qLocation, loc_filename
5526#if MIN_VERSION_template_haskell(2,7,0)
5627 , Quasi(qAddDependentFile)
5728#endif
5829 )
59−#if MIN_VERSION_template_haskell(2,16,0)
60−import Language.Haskell.TH ( mkBytes, bytesPrimL )
61−import qualified Data.ByteString.Internal as B
62−#endif
6330import System.Directory (doesDirectoryExist, doesFileExist,
64− getDirectoryContents, canonicalizePath)
65−import Control.Exception (throw, tryJust, ErrorCall(..))
66−import Control.Monad (filterM, guard)
31+ getDirectoryContents)
32+import Control.Monad (filterM)
6733import qualified Data.ByteString as B
6834import qualified Data.ByteString.Char8 as B8
69−import Control.Arrow ((&&&), second)
35+import Control.Arrow ((&&&), second, first)
7036import Control.Applicative ((<$>))
37+import Data.Monoid (mappend)
7138import Data.ByteString.Unsafe (unsafePackAddressLen)
72−import System.IO.Error (isDoesNotExistError)
7339import System.IO.Unsafe (unsafePerformIO)
74−import System.FilePath ((</>), takeDirectory, takeExtension)
75−import Data.String (fromString)
76−import Prelude as P
77−import Data.List (sortBy)
78−import Data.Ord (comparing)
7940
8041-- | Embed a single file in your source code.
8142--
@@ -90,78 +51,14 @@ embedFile fp =
9051#endif
9152 (runIO $ B.readFile fp) >>= bsToExp
9253
93−-- | Maybe embed a single file in your source code depending on whether or not file exists.
94−--
95−-- Warning: When a build is compiled with the file missing, a recompile when the file exists might not trigger an embed of the file.
96−-- You might try to fix this by doing a clean build.
97−--
98−-- > import qualified Data.ByteString
99−-- >
100−-- > maybeMyFile :: Maybe Data.ByteString.ByteString
101−-- > maybeMyFile = $(embedFileIfExists "dirName/fileName")
102−--
103−-- @since 0.0.14.0
104−embedFileIfExists :: FilePath -> Q Exp
105−embedFileIfExists fp = do
106− mbs <- runIO maybeFile
107− case mbs of
108− Nothing -> [| Nothing |]
109− Just bs -> do
110−#if MIN_VERSION_template_haskell(2,7,0)
111− qAddDependentFile fp
112−#endif
113− [| Just $(bsToExp bs) |]
114− where
115− maybeFile :: IO (Maybe B.ByteString)
116− maybeFile =
117− either (const Nothing) Just <$>
118− tryJust (guard . isDoesNotExistError) (B.readFile fp)
119−
120−-- | Embed a single existing file in your source code
121−-- out of list a list of paths supplied.
122−--
123−-- > import qualified Data.ByteString
124−-- >
125−-- > myFile :: Data.ByteString.ByteString
126−-- > myFile = $(embedOneFileOf [ "dirName/fileName", "src/dirName/fileName" ])
127−embedOneFileOf :: [FilePath] -> Q Exp
128−embedOneFileOf ps =
129− (runIO $ readExistingFile ps) >>= \ ( path, content ) -> do
130−#if MIN_VERSION_template_haskell(2,7,0)
131− qAddDependentFile path
132−#endif
133− bsToExp content
134− where
135− readExistingFile :: [FilePath] -> IO ( FilePath, B.ByteString )
136− readExistingFile xs = do
137− ys <- filterM doesFileExist xs
138− case ys of
139− (p:_) -> B.readFile p >>= \ c -> return ( p, c )
140− _ -> throw $ ErrorCall "Cannot find file to embed as resource"
141−
142−-- | Embed a directory recursively in your source code.
54+-- | Embed a directory recusrively in your source code.
14355--
14456-- > import qualified Data.ByteString
14557-- >
14658-- > myDir :: [(FilePath, Data.ByteString.ByteString)]
14759-- > myDir = $(embedDir "dirName")
14860embedDir :: FilePath -> Q Exp
149−embedDir fp = do
150− typ <- [t| [(FilePath, B.ByteString)] |]
151− e <- ListE <$> ((runIO $ fileList fp) >>= mapM (pairToExp fp))
152− return $ SigE e typ
153−
154−-- | Embed a directory listing recursively in your source code.
155−--
156−-- > myFiles :: [FilePath]
157−-- > myFiles = $(embedDirListing "dirName")
158−--
159−-- @since 0.0.11
160−embedDirListing :: FilePath -> Q Exp
161−embedDirListing fp = do
162− typ <- [t| [FilePath] |]
163− e <- ListE <$> ((runIO $ fmap fst <$> fileList fp) >>= mapM strToExp)
164− return $ SigE e typ
61+embedDir fp = ListE <$> ((runIO $ fileList fp) >>= mapM pairToExp)
16562
16663-- | Get a directory tree in the IO monad.
16764--
@@ -169,117 +66,51 @@ embedDirListing fp = do
16966getDir :: FilePath -> IO [(FilePath, B.ByteString)]
17067getDir = fileList
17168
172−pairToExp :: FilePath -> (FilePath, B.ByteString) -> Q Exp
173−pairToExp _root (path, bs) = do
69+pairToExp :: (FilePath, B.ByteString) -> Q Exp
70+pairToExp (path, bs) = do
17471#if MIN_VERSION_template_haskell(2,7,0)
175− qAddDependentFile $ _root ++ '/' : path
72+ qAddDependentFile path
17673#endif
17774 exp' <- bsToExp bs
178− return $! TupE
179−#if MIN_VERSION_template_haskell(2,16,0)
180− $ map Just
181−#endif
182− [LitE $ StringL path, exp']
75+ return $! TupE [LitE $ StringL path, exp']
18376
18477bsToExp :: B.ByteString -> Q Exp
185−#if MIN_VERSION_template_haskell(2, 5, 0)
186−bsToExp bs =
187− return $ VarE 'unsafePerformIO
188− `AppE` (VarE 'unsafePackAddressLen
189− `AppE` LitE (IntegerL $ fromIntegral $ B8.length bs)
190−#if MIN_VERSION_template_haskell(2, 16, 0)
191− `AppE` LitE (bytesPrimL (
192− let B.PS ptr off sz = bs
193− in mkBytes ptr (fromIntegral off) (fromIntegral sz))))
194−#elif MIN_VERSION_template_haskell(2, 8, 0)
195− `AppE` LitE (StringPrimL $ B.unpack bs))
196−#else
197− `AppE` LitE (StringPrimL $ B8.unpack bs))
198−#endif
199−#else
20078bsToExp bs = do
20179 helper <- [| stringToBs |]
20280 let chars = B8.unpack bs
20381 return $! AppE helper $! LitE $! StringL chars
204−#endif
20582
20683stringToBs :: String -> B.ByteString
20784stringToBs = B8.pack
20885
209−-- | Embed a single file in your source code.
210−--
211−-- > import Data.String
212−-- >
213−-- > myFile :: IsString a => a
214−-- > myFile = $(embedStringFile "dirName/fileName")
215−--
216−-- Since 0.0.9
217−embedStringFile :: FilePath -> Q Exp
218−embedStringFile fp =
219−#if MIN_VERSION_template_haskell(2,7,0)
220− qAddDependentFile fp >>
221−#endif
222− (runIO $ P.readFile fp) >>= strToExp
223−
224−-- | Embed a single existing string file in your source code
225−-- out of list a list of paths supplied.
226−--
227−-- Since 0.0.9
228−embedOneStringFileOf :: [FilePath] -> Q Exp
229−embedOneStringFileOf ps =
230− (runIO $ readExistingFile ps) >>= \ ( path, content ) -> do
231−#if MIN_VERSION_template_haskell(2,7,0)
232− qAddDependentFile path
233−#endif
234− strToExp content
235− where
236− readExistingFile :: [FilePath] -> IO ( FilePath, String )
237− readExistingFile xs = do
238− ys <- filterM doesFileExist xs
239− case ys of
240− (p:_) -> P.readFile p >>= \ c -> return ( p, c )
241− _ -> throw $ ErrorCall "Cannot find file to embed as resource"
242−
243−strToExp :: String -> Q Exp
244−#if MIN_VERSION_template_haskell(2, 5, 0)
245−strToExp s =
246− return $ VarE 'fromString
247− `AppE` LitE (StringL s)
248−#else
249−strToExp s = do
250− helper <- [| fromString |]
251− return $! AppE helper $! LitE $! StringL s
252−#endif
253−
25486notHidden :: FilePath -> Bool
25587notHidden ('.':_) = False
25688notHidden _ = True
25789
25890fileList :: FilePath -> IO [(FilePath, B.ByteString)]
259−fileList top = fileList' top ""
91+fileList top = map (first tail) <$> fileList' top ""
26092
26193fileList' :: FilePath -> FilePath -> IO [(FilePath, B.ByteString)]
26294fileList' realTop top = do
263− allContents <- filter notHidden <$> getDirectoryContents (realTop </> top)
264− let all' = map ((top </>) &&& (\x -> realTop </> top </> x)) allContents
95+ let prefix1 = top ++ "/"
96+ prefix2 = realTop ++ prefix1
97+ allContents <- filter notHidden <$> getDirectoryContents prefix2
98+ let all' = map (mappend prefix1 &&& mappend prefix2) allContents
26599 files <- filterM (doesFileExist . snd) all' >>=
266100 mapM (liftPair2 . second B.readFile)
267101 dirs <- filterM (doesDirectoryExist . snd) all' >>=
268102 mapM (fileList' realTop . fst)
269− return $ sortBy (comparing fst) $ concat $ files : dirs
103+ return $ concat $ files : dirs
270104
271105liftPair2 :: Monad m => (a, m b) -> m (a, b)
272106liftPair2 (a, b) = b >>= \b' -> return (a, b')
273107
274−magic :: B.ByteString -> B.ByteString
275−magic x = B8.concat ["fe", x]
276−
277−sizeLen :: Int
108+magic = concat ["fe", "MS"]
278109sizeLen = 20
279110
280111getInner :: B.ByteString -> B.ByteString
281112getInner b =
282− let (sizeBS, rest) = B.splitAt sizeLen b
113+ let (sizeBS, rest) = B.splitAt sizeLen $ B.drop (length magic) b
283114 in case reads $ B8.unpack sizeBS of
284115 (i, _):_ -> B.take i rest
285116 [] -> error "Data.FileEmbed (getInner): Your dummy space has been corrupted."
@@ -290,152 +121,40 @@ padSize i =
290121 in replicate (sizeLen - length s) '0' ++ s
291122
292123#if MIN_VERSION_template_haskell(2,5,0)
293−-- | Allocate the given number of bytes in the generate executable. That space
294−-- can be filled up with the 'inject' and 'injectFile' functions.
295124dummySpace :: Int -> Q Exp
296−dummySpace = dummySpaceWith "MS"
297−
298−-- | Like 'dummySpace', but takes a postfix for the magic string. In
299−-- order for this to work, the same postfix must be used by 'inject' /
300−-- 'injectFile'. This allows an executable to have multiple
301−-- 'ByteString's injected into it, without encountering collisions.
302−--
303−-- Since 0.0.8
304−dummySpaceWith :: B.ByteString -> Int -> Q Exp
305−dummySpaceWith postfix space = do
125+dummySpace space = do
306126 let size = padSize space
307− magic' = magic postfix
308− start = B8.unpack magic' ++ size
309− magicLen = B8.length magic'
310− len = magicLen + sizeLen + space
311− chars = LitE $ StringPrimL $
312−#if MIN_VERSION_template_haskell(2,6,0)
313− map (toEnum . fromEnum) $
314−#endif
315− start ++ replicate space '0'
316− [| getInner (B.drop magicLen (unsafePerformIO (unsafePackAddressLen len $(return chars)))) |]
127+ let start = magic ++ size
128+ let chars = LitE $ StringPrimL $ start ++ replicate space '0'
129+ let len = LitE $ IntegerL $ fromIntegral $ length start + space
130+ upi <- [|unsafePerformIO|]
131+ pack <- [|unsafePackAddressLen|]
132+ getInner' <- [|getInner|]
133+ return $ getInner' `AppE` (upi `AppE` (pack `AppE` len `AppE` chars))
317134#endif
318135
319−-- | Inject some raw data inside a @ByteString@ containing empty, dummy space
320−-- (allocated with @dummySpace@). Typically, the original @ByteString@ is an
321−-- executable read from the filesystem.
322136inject :: B.ByteString -- ^ bs to inject
323137 -> B.ByteString -- ^ original BS containing dummy
324138 -> Maybe B.ByteString -- ^ new BS, or Nothing if there is insufficient dummy space
325−inject = injectWith "MS"
326−
327−-- | Like 'inject', but takes a postfix for the magic string.
328−--
329−-- Since 0.0.8
330−injectWith :: B.ByteString -- ^ postfix of magic string
331− -> B.ByteString -- ^ bs to inject
332− -> B.ByteString -- ^ original BS containing dummy
333− -> Maybe B.ByteString -- ^ new BS, or Nothing if there is insufficient dummy space
334−injectWith postfix toInj orig =
139+inject toInj orig =
335140 if toInjL > size
336141 then Nothing
337− else Just $ B.concat [before, magic', B8.pack $ padSize toInjL, toInj, B8.pack $ replicate (size - toInjL) '0', after]
142+ else Just $ B.concat [before, B8.pack magic, B8.pack $ padSize toInjL, toInj, B8.pack $ replicate (size - toInjL) '0', after]
338143 where
339− magic' = magic postfix
340144 toInjL = B.length toInj
341− (before, rest) = B.breakSubstring magic' orig
342− (sizeBS, rest') = B.splitAt sizeLen $ B.drop (B8.length magic') rest
145+ (before, rest) = B.breakSubstring (B8.pack magic) orig
146+ (sizeBS, rest') = B.splitAt sizeLen $ B.drop (length magic) rest
343147 size = case reads $ B8.unpack sizeBS of
344148 (i, _):_ -> i
345149 [] -> error $ "Data.FileEmbed (inject): Your dummy space has been corrupted. Size is: " ++ show sizeBS
346− after = B.drop size rest'
150+ (dummy, after) = B.splitAt size rest'
347151
348−-- | Same as 'inject', but instead of performing the injecting in memory, read
349−-- the contents from the filesystem and write back to a different file on the
350−-- filesystem.
351−injectFile :: B.ByteString -- ^ bs to inject
152+injectFile :: B.ByteString
352153 -> FilePath -- ^ template file
353154 -> FilePath -- ^ output file
354155 -> IO ()
355−injectFile = injectFileWith "MS"
356−
357−-- | Like 'injectFile', but takes a postfix for the magic string.
358−--
359−-- Since 0.0.8
360−injectFileWith :: B.ByteString -- ^ postfix of magic string
361− -> B.ByteString -- ^ bs to inject
362− -> FilePath -- ^ template file
363− -> FilePath -- ^ output file
364− -> IO ()
365−injectFileWith postfix inj srcFP dstFP = do
156+injectFile inj srcFP dstFP = do
366157 src <- B.readFile srcFP
367− case injectWith postfix inj src of
158+ case inject inj src of
368159 Nothing -> error "Insufficient dummy space"
369160 Just dst -> B.writeFile dstFP dst
370−
371−{- $inject
372−
373−The inject system allows arbitrary content to be embedded inside a Haskell
374−executable, post compilation. Typically, file-embed allows you to read some
375−contents from the file system at compile time and embed them inside your
376−executable. Consider a case, instead, where you would want to embed these
377−contents after compilation. Two real-world examples are:
378−
379−* You would like to embed a hash of the executable itself, for sanity checking in a network protocol. (Obviously the hash will change after you embed the hash.)
380−
381−* You want to create a self-contained web server that has a set of content, but will need to update the content on machines that do not have access to GHC.
382−
383−The typical workflow use:
384−
385−* Use 'dummySpace' or 'dummySpaceWith' to create some empty space in your executable
386−
387−* Use 'injectFile' or 'injectFileWith' from a separate utility to modify that executable to have the updated content.
388−
389−The reason for the @With@-variant of the functions is for cases where you wish
390−to inject multiple different kinds of content, and therefore need control over
391−the magic key. If you know for certain that there will only be one dummy space
392−available, you can use the non-@With@ variants.
393−
394−-}
395−
396−-- | Take a relative file path and attach it to the root of the current
397−-- project.
398−--
399−-- The idea here is that, when building with Stack, the build will always be
400−-- executed with a current working directory of the root of the project (where
401−-- your .cabal file is located). However, if you load up multiple projects with
402−-- @stack ghci@, the working directory may be something else entirely.
403−--
404−-- This function looks at the source location of the Haskell file calling it,
405−-- finds the first parent directory with a .cabal file, and uses that as the
406−-- root directory for fixing the relative path.
407−--
408−-- @$(makeRelativeToProject "data/foo.txt" >>= embedFile)@
409−--
410−-- @since 0.0.10
411−makeRelativeToProject :: FilePath -> Q FilePath
412−makeRelativeToProject = makeRelativeToLocationPredicate $ (==) ".cabal" . takeExtension
413−
414−-- | Take a predicate to infer the project root and a relative file path, the given file path is then attached to the inferred project root
415−--
416−-- This function looks at the source location of the Haskell file calling it,
417−-- finds the first parent directory with a file matching the given predicate, and uses that as the
418−-- root directory for fixing the relative path.
419−--
420−-- @$(makeRelativeToLocationPredicate ((==) ".cabal" . takeExtension) "data/foo.txt" >>= embedFile)@
421−--
422−-- @since 0.0.15.0
423−makeRelativeToLocationPredicate :: (FilePath -> Bool) -> FilePath -> Q FilePath
424−makeRelativeToLocationPredicate isTargetFile rel = do
425− loc <- qLocation
426− runIO $ do
427− srcFP <- canonicalizePath $ loc_filename loc
428− mdir <- findProjectDir srcFP
429− case mdir of
430− Nothing -> error $ "Could not find .cabal file for path: " ++ srcFP
431− Just dir -> return $ dir </> rel
432− where
433− findProjectDir x = do
434− let dir = takeDirectory x
435− if dir == x
436− then return Nothing
437− else do
438− contents <- getDirectoryContents dir
439− if any isTargetFile contents
440− then return (Just dir)
441− else findProjectDir dir