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afp-udcfix.hs
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afp-udcfix.hs
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module Main where
import OpenAFP
import qualified Data.Map as Map
import qualified Data.ByteString as S
import qualified Data.ByteString.Unsafe as S
import qualified Data.ByteString.Char8 as C
import qualified Data.ByteString.Lazy as L
import Data.Int
import Text.Regex.Posix
import Text.Regex.Base.RegexLike
import Data.Hashable (Hashable(..))
-- | Flags.
type VarsIO a = StateIO Vars a
-- | Global configuration parameters.
dbcsSpace, dbcsFirst :: NChar
dbcsSpace = (0x40, 0x40)
dbcsFirst = (0x4C, 0x41)
isUDC :: N1 -> Bool
isUDC hi = hi >= 0x92 && hi <= 0xFE
{-# NOINLINE _Vars #-}
_Vars :: IORef Vars
_Vars = unsafePerformIO $ newIORef undefined
-- | The main program: initialize global variables, split the input
-- AFP file into "pages", then dispatch each page to pageHandler.
main :: IO ()
main = do
writeIORef _Vars =<< initVars
stateMain
instance MonadReader Vars IO where
ask = readIORef _Vars
local = undefined
stateMain = do
chunks <- liftOpt readInputAFP
fh <- liftOpt openOutputAFP
forM_ (splitRecords _PGD chunks) $ \cs -> do
cs' <- pageHandler cs
io $ L.hPutStr fh (encodeList cs')
io $ hClose fh
-- | Check a page's PTX records for UDC characters. If none is seen,
-- simply output the page; otherwise pass the page to udcPageHandler
-- and output the result.
pageHandler page = (`catchError` hdl) $ do
page ..>
[ _MCF ... mcfHandler
, _MCF1 ... mcf1Handler
, _PTX ... ptxCheckUDC
]
return page
where
hdl err | Just e <- cast err, isUserError e = udcPageHandler page
| otherwise = throwError err
-- | Record font Id to Name mappings in MCF's RLI and FQN chunks.
mcfHandler r = do
readChunks r ..>
[ _MCF_T ... \mcf -> do
let cs = readChunks mcf
ids <- sequence [ t_rli `applyToChunk` c | c <- cs, c ~~ _T_RLI ]
fonts <- sequence [ t_fqn `applyToChunk` c | c <- cs, c ~~ _T_FQN ]
_IdToFont %%= (ids `zip` map packAStr fonts)
]
-- | Record font Id to Name mappings in MCF1's Data chunks.
mcf1Handler r = do
_IdToFont %%=
[ (mcf1_CodedFontLocalId mcf1, packA8 $ mcf1_CodedFontName mcf1)
| Record mcf1 <- readData r
]
-- | Split PTX into "groups", each one begins with a SCFL chunk.
ptxCheckUDC r = length groups `seq` forM_ groups ptxGroupCheckUDC
where
groups = splitRecords _PTX_SCFL chunks
chunks = filter want (readChunks r)
want c = (c ~~ _PTX_SCFL) || (c ~~ _PTX_TRN)
-- | Check a PTX to see if the leading SCFL indicates a DBCS font;
-- if yes, pass remaining TRN chunks to trnCheckUDC.
ptxGroupCheckUDC [] = return ()
ptxGroupCheckUDC (scfl:trnList) = seq (length trnList) $ do
font <- readArray _IdToFont =<< ptx_scfl `applyToChunk` scfl
isDBCS <- fontIsDBCS &: font
when (isDBCS) . io $ do
forM_ (map (ptx_trn `applyToChunk`) trnList)
(>>= trnCheckUDC)
-- | Look inside TRN buffers for UDC characters. If we find one,
-- raise an IO exception so the page handler can switch to UDC mode.
trnCheckUDC :: NStr -> IO ()
trnCheckUDC nstr = S.unsafeUseAsCStringLen (packBuf nstr) $ \(cstr, len) -> do
forM_ [0, 2..len-1] $ \off -> do
hi <- peekByteOff cstr off
when (isUDC hi) $ do
throwError (strMsg "Found UDC")
-- | The main handler for pages with UDC characters.
udcPageHandler page = do
(_X $= id) 0
(_Y $= id) 0
(_UDC $= id) []
page ==>
[ _PGD ... _XPageSize $= pgd_XPageSize
, _MCF ... mcfHandler
, _MCF1 ... mcf1Handler
, _PTX === \ptx -> do
filterChunks ptx
[ _PTX_AMI ... _X $= ptx_ami
, _PTX_AMB ... _Y $= ptx_amb
, _PTX_RMI ... _X += ptx_rmi
, _PTX_RMB ... _Y += ptx_rmb
, _PTX_SCFL ... _FontId $= ptx_scfl
, _PTX_SBI ... _BaselineIncr $= ptx_sbi
, _PTX_SIM ... _InlineMargin $= ptx_sim
, _PTX_STO ... \sto -> do
_XOrientation $= ptx_sto_Orientation $ sto
_YOrientation $= ptx_sto_WrapDirection $ sto
, _PTX_BLN ... \_ -> do
x' <- readVar _InlineMargin
y' <- readVar _BaselineIncr
(_X $= id) x'
(_Y += id) y'
, _PTX_TRN === trnHandler
]
, _EMO === endPageHandler
, _EPG === endPageHandler
]
trnHandler r = do
font <- currentFont
let trn = packNStr $ ptx_trn r
isDBCS <- fontIsDBCS &: font
case isDBCS of
True -> do
-- If font is double byte, transform the TRN with dbcsHandler.
db <- dbcsHandler font trn -- XXX
push r{ ptx_trn = mkBuf db }
False -> do
-- If font is single byte, simply add each byte's increments.
-- without parsing UDC.
let f tot ch = do
inc <- incrementOf font (0x00, if ch == 0x00 then 0x40 else N1 ch)
return (tot + inc)
inc <- foldM f 0 (S.unpack trn)
(_X += id) inc
push r
dbcsHandler :: FontField -> ByteString -> VarsIO ByteString
dbcsHandler font bs = liftM (S.pack . map fromN1) (dbcsHandler' font (map N1 (S.unpack bs)))
dbcsHandler' :: FontField -> [N1] -> VarsIO [N1]
dbcsHandler' _ [] = return []
dbcsHandler' _ [x] = do
warn $ "invalid DBCS sequence: " ++ show x
return []
dbcsHandler' font (hi:lo:xs) = do
(incChar, (hi', lo')) <- dbcsCharHandler font (hi, lo)
incr <- incrementOf font incChar
(_X += id) incr
rest <- dbcsHandler' font xs
return (hi':lo':rest)
dbcsCharHandler font char@(hi, _)
| isUDC hi = do
x <- readVar _X
y <- readVar _Y
_UDC @= CharUDC
{ udcX = x
, udcY = y
, udcChar = char
, udcFont = font
}
return (char, dbcsSpace)
| otherwise = return (dbcsFirst, char)
-- isNotDBCS hi = return (char, char)
endPageHandler r = do
udcList <- readVar _UDC
unless (null udcList) $ do
xp <- readVar _XPageSize
xo <- readVar _XOrientation
yo <- readVar _YOrientation
forM_ (reverse udcList) $ \udc -> do
infoMaybe <- getFontInfo (udcFont udc) (udcChar udc)
case infoMaybe of
Just info | S.length (fromBuf0 $ fontBitmap info) > 0 -> do
push _BII
push _IOC
{ ioc_XMap = 0x03E8
, ioc_XOrientation = xo
, ioc_YMap = 0x03E8
, ioc_YOrientation = yo
}
udcCharHandler xp yo udc info
push _EII
_ -> return ()
push r
udcCharHandler xp yo char info = do
base <- adjustY &: fontBaseOffset info
let (x, y) = orientate x' y'
x' = udcX char + (fromIntegral $ fontASpace info)
y' = udcY char - (fromIntegral $ base)
push _IID
{ iid_Color = 0x0008
, iid_ConstantData1 = 0x000009600960000000000000
, iid_ConstantData2 = 0x000000002D00
, iid_XUnits = fontResolution info
, iid_YUnits = fontResolution info
}
push _ICP
{ icp_XCellOffset = x
, icp_XCellSize = fontWidth info
, icp_XFillSize = fontWidth info
, icp_YCellOffset = y
, icp_YCellSize = fontHeight info
, icp_YFillSize = fontHeight info
}
push _IRD {
ird_ImageData = fontBitmap info
}
where
orientate x y
| (yo == 0x5a00) = (xp - y, x)
| otherwise = (x, y)
currentFont = readArray _IdToFont =<< readVar _FontId
incrementOf x y = do
cachedLibReader _IncrCache fillInc 0 x y
where
fillInc font char@(hi, _) f redo = do
rv <- readIncrements font hi
if rv then liftM (maybe 0 id) redo else do
udcRef <- asks _UDC
io $ do
-- Remove this from the list of UDCs to gen image for
putStrLn $ "Skipping unknown UDC: " ++ show char ++ ", font: " ++ show (ck_font f)
modifyIORef udcRef (filter ((/= char) . udcChar))
return 0
getFontInfo x y = do
cachedLibReader _InfoCache fillInfo (Just _FontInfo) x y
where
fillInfo font char key _ = do
infoMaybe <- readFontInfo font char
case infoMaybe of
Just info -> do
_InfoCache %= (key, infoMaybe)
_IncrCache %= (key, fontIncrement info)
return infoMaybe
_ -> return Nothing
cachedLibReader :: (MonadIO m, MonadReader Vars m, MonadPlus m, MonadError e m, Show e, Typeable e) =>
(Vars -> HashTable CacheKey a)
-> (ByteString -> NChar -> CacheKey -> m (Maybe a) -> m a)
-> a -> FontField -> NChar -> m a
cachedLibReader cache filler fallback font char = do
vars <- ask
let val = io $ hashLookup (cache vars) key
fillCache = filler font char key val
val >>= maybe (fillCache `catchError` hdl) return
where
key = cacheKey font char
hdl err | Just e <- cast err, isUserError e = {-# SCC "hdl" #-} do
let keySeen = cacheKey font (0x00, 0x00)
seen <- cache %? keySeen
when (isNothing seen) $ do
warn $ "font library does not exist: " ++ C.unpack font
cache %= (key, fallback)
cache %= (keySeen, fallback)
-- sequence_ [ cache %= (cacheKey font (fst char, lo), fallback) | <- [0x00 .. 0xFF] ]
return fallback
| otherwise = throwError err
readIncrements font hi = do
cfi <- (_CFI <~~) =<< readFontlibAFP &<< font
case hi `matchRecordMaybe` cfi_Section $ cfi of
Nothing -> return False
Just cfi' -> do
fni <- _FNI `readLibRecord` cfi_FontCharacterSetName $ cfi'
cpi <- _CPI `readLibRecord` cfi_CodePageName $ cfi'
let gcgToIncr = Map.fromList . map (pair . fromRecord) $ readData fni
pair r = (fni_GCGID r, fni_CharacterIncrement r)
incr = maybe 0 id . (`Map.lookup` gcgToIncr) . cpi_GCGID
sequence_ [ _IncrCache %= (key r, incr r) | Record r <- readData cpi ]
return True
where
key r = cacheKey font (hi, cpi_CodePoint r)
readFontInfo font char@(hi, _) = do
cfi <- (_CFI <~~) =<< readFontlibAFP &<< font
case (hi `matchRecordMaybe` cfi_Section) cfi of
Nothing -> return Nothing
Just cfi' -> liftM Just (cfiHandler char cfi')
cfiHandler char@(_, lo) cfi = do
cpi_ <- _CPI `readLibRecord` cfi_CodePageName $ cfi
case lo `matchRecordMaybe` cpi_CodePoint $ cpi_ of
Nothing -> return _FontInfo
Just c -> run lo (cpi_GCGID c) cfi
where
run 0x40 0 x = return _FontInfo
run _ 0 x = cfiHandler (0x00, 0x40) x
run _ gcg x = do
io $ putStrLn ("Replacing UDC: " ++ show char)
fcsHandler gcg x
fcsHandler gcg cfi = do
fcs <- readFontlibAFP &<< (fromFontField $ cfi_FontCharacterSetName cfi)
fni_ <- _FNI <~~ fcs
fnm_ <- _FNM <~~ fcs
fnc <- _FNC <~~ fcs
let fni = gcg `matchRecord` fni_GCGID $ fni_
fnm = fromRecord $ readData fnm_ `genericIndex` fni_FNMCount fni
(w, h) = (1 + fnm_Width fnm, 1 + fnm_Height fnm)
bytes = ((w + 7) `div` 8) * h
fngs <- sequence [ fng `applyToChunk` n | n <- fcs, n ~~ _FNG ]
let bitmap = subBufs fngs (fnm_Offset fnm) bytes
vars <- ask
when (verbose (_Opts vars)) $ do
let nstr = fromNStr bitmap
showBitmap nstr (bytes `div` h)
return FontInfo
{ fontIncrement = fni_CharacterIncrement fni
, fontAscend = fni_AscendHeight fni
, fontDescend = fni_DescendDepth fni
, fontASpace = fni_ASpace fni
, fontBSpace = fni_BSpace fni
, fontCSpace = fni_CSpace fni
, fontBaseOffset = fni_BaseOffset fni
, fontBitmap = bitmap
, fontWidth = w
, fontHeight = h
, fontResolution = fnc_UnitXValue fnc
}
readLibRecord t f r = t `seq` f `seq` r `seq` ((t <~~) =<< readFontlibAFP &<< (fromFontField $ f r))
-- | Data structures.
data CharUDC = CharUDC
{ udcX :: !N2
, udcY :: !N2
, udcChar :: !NChar
, udcFont :: !FontField
} deriving (Show)
data FontInfo = FontInfo
{ fontIncrement :: !N2
, fontAscend :: !I2
, fontDescend :: !I2
, fontASpace :: !I2
, fontBSpace :: !N2
, fontCSpace :: !I2
, fontBaseOffset :: !I2
, fontBitmap :: !NStr
, fontWidth :: !N2
, fontHeight :: !N2
, fontResolution :: !N2
} deriving (Show)
_FontInfo = FontInfo 0 0 0 0 0 0 0 _NStr 0 0 0
-- | Simple test case.
run :: IO ()
run = withArgs (words "-a -d NS.. -i tmp -o x -f /StreamEDP/fontlib") main
data Vars = Vars
{ _XPageSize :: !(IORef N2)
, _X :: !(IORef N2)
, _Y :: !(IORef N2)
, _XOrientation :: !(IORef N2)
, _YOrientation :: !(IORef N2)
, _InlineMargin :: !(IORef N2)
, _BaselineIncr :: !(IORef N2)
, _FontId :: !(IORef N1)
, _UDC :: !(IORef [CharUDC])
, _IdToFont :: !(IOArray N1 FontField)
, _InfoCache :: !(HashTable CacheKey (Maybe FontInfo))
, _IncrCache :: !(HashTable CacheKey N2)
, _Opts :: !Opts
}
type Config = Int
data CacheKey = MkCacheKey
{ ck_hash :: !Int
, ck_font :: !ByteString
}
deriving Eq
instance Hashable CacheKey where
hashWithSalt salt = hashWithSalt salt . ck_hash
cacheKey :: ByteString -> NChar -> CacheKey
cacheKey font (hi, lo) = MkCacheKey
(hash (fromEnum hi, fromEnum lo, font))
font
initVars :: IO Vars
initVars = do
xp <- newIORef 0
x <- newIORef 0
y <- newIORef 0
xo <- newIORef 0
yo <- newIORef 0
im <- newIORef 0
bi <- newIORef 0
fid <- newIORef 0
udc <- newIORef []
idf <- newIOArray (0x00, 0xFF) C.empty
ifc <- hashCreate
inc <- hashCreate
opt <- getOpts
return $ Vars xp x y xo yo im bi fid udc idf ifc inc opt
getOpts = do
args <- getArgs
(optsIO, rest, errs) <- return . getOpt Permute options
$ if (null args) then ["-h"] else args
let opts = foldl (flip ($)) defaultOpts optsIO
suffix = fontlibSuffix opts
showHelp opts
unless (null rest) $ do
warn $ "unrecognized arguments: `" ++ concat (intersperse " " rest) ++ "'\n"
paths <- filterM checkPath $ fontlibPaths opts
when (null paths) $ do
die $ "cannot find a valid font library path"
fontIsDBCS opts `seq` forM_ errs warn
return opts{ readFontlibAFP = reader paths (fontlibSuffix opts) }
where
checkPath path = do
exists <- doesDirectoryExist (C.unpack path)
unless (exists) $ do
warn $ "directory does not exist: `" ++ C.unpack path ++ "'"
return exists
reader paths suffix name = do
-- Here we memoize by name.
let key = C.concat (suffix:name:paths)
rv <- hashLookup _ReaderCache key
case rv of
Just chunks -> return chunks
_ -> do
(afp:_) <- filterM doesFileExist
[ C.unpack f ++ "/" ++ fileName ++ C.unpack suffix | f <- paths ]
chunks <- readAFP afp
hashInsert _ReaderCache key (seq (length chunks) chunks)
return chunks
where
fileName = case C.unpack name of
('X':_:xs) -> trim ('X':'0':xs)
xs -> trim xs
{-# NOINLINE _ReaderCache #-}
_ReaderCache :: HashTable ByteString [AFP_]
_ReaderCache = unsafePerformIO hashCreate
infixl 4 &:
l &: v = do
vars <- ask
return $ l (_Opts vars) v
infixl 4 &<<
l &<< v = do
vars <- ask
io $ l (_Opts vars) v
liftOpt l = do
vars <- ask
io $ l (_Opts vars)
defaultOpts = Opts
{ adjustY = id
, fontIsDBCS = const $ requiredOpt usage "dbcs-pattern"
, dbcsPattern = Nothing
, readInputAFP = fail $ requiredOpt usage "input"
, openOutputAFP = fail $ requiredOpt usage "output"
, readFontlibAFP = const $ error "fontlib" -- calculated with the two fields below
, fontlibPaths = [C.pack "fontlib"]
, fontlibSuffix = C.empty
, cstrlenCheckUDC = checkUDC
, trnToSegments = dbcsHandler
, verbose = False
, showHelp = return ()
}
where
checkUDC (cstr, len) = forM_ [0, 2..len-1] $ \off -> do
hi <- peekByteOff cstr off
when (isUDC hi) $ fail "UDC"
usage :: String -> IO a
usage = showUsage options showInfo
showInfo prg =
"Usage: " ++ prg ++ " -i FILE -o FILE\n" ++
"( example: " ++ prg ++ " -a -s .afp -d M..T -i in.afp -o out.afp )"
options :: [OptDescr (Opts -> Opts)]
options =
[ noArg "a" ["adjust"] "Adjust baseline offset"
(\o -> o { adjustY = \y -> (y * 13) `div` 16 })
, reqArg "c" ["codepage"] "835|947" "UDC codepage (default: 835)"
setCodepage
, reqArg "d" ["dbcs-pattern"] "REGEXP" "DBCS font name pattern"
(\s o -> o { fontIsDBCS = setMatchDBCS (C.pack s)
, dbcsPattern = Just (C.pack s) })
, reqArg "f" ["fontlib-path"] "PATH,PATH..." "Paths to font libraries"
(\s o -> o { fontlibPaths = C.split ',' (C.pack s) })
, reqArg "i" ["input"] "FILE" "Input AFP file"
(\s o -> o { readInputAFP = readAFP s })
, reqArg "o" ["output"] "FILE" "Output AFP file"
(\s o -> o { openOutputAFP = openBinaryFile s WriteMode })
, reqArg "s" ["fontlib-suffix"] ".SUFFIX" "Font library file suffix"
(\s o -> o { fontlibSuffix = C.pack s })
, noArg "v" ["verbose"] "Print progress information"
(\o -> o { verbose = True })
, noArg "h" ["help"] "Show help"
(\o -> o { showHelp = usage "" })
]
where
_M__T = C.pack "M..T"
_NS__ = C.pack "NS.."
_NS = C.pack "NS"
setMatchDBCS s a
| s == _M__T = (C.length a >= 6) && ((C.index a 2 == 'M') || (C.index a 5 == 'T'))
| s == _NS__ = (C.length a >= 6) && ((C.index a 2 == 'N') || (C.index a 3 == 'S'))
| s == _NS = (C.length a >= 4) && ((C.index a 2 == 'N') || (C.index a 3 == 'S'))
| otherwise = (C.unpack a =~ C.unpack s)
setCodepage "835" = id
setCodepage "947" = \o -> o
{ cstrlenCheckUDC = checkUDC
, trnToSegments = segment
-- if dbcsPattern is not set, set fontIsDBCS to (const True).
, fontIsDBCS = maybe (const True)
(const . fontIsDBCS $ o)
$ dbcsPattern o
}
setCodepage s = unsafePerformIO $ do
usage $ "invalid codepage:" ++ s
checkUDC cstrlen = do
str <- peekCStringLen cstrlen
unless (str =~ noUDC) $ fail "UDC"
noUDC = "^([\x00-\x7f]+|([\xA1-\xC5\xC9-\xF9].)+|(\xC6[^\xA1-\xFE])+)$"
segment = error "segment"
type NChar = (N1, N1)
type FontField = ByteString
fromFontField = packA8
data Segment
= SegmentUDC
{ segmentChar :: !NChar
, segmentReplace :: !NChar
}
| SegmentDBCS
{ segmentChar :: !NChar
, segmentLength :: Int
}
| SegmentByte
{ segmentByte :: [N1]
}
deriving (Show, Typeable)
data Opts = Opts
{ fontIsDBCS :: !(FontField -> Bool)
, dbcsPattern :: !(Maybe ByteString)
, adjustY :: !(I2 -> I2)
, readInputAFP :: !(IO [AFP_])
, openOutputAFP :: !(IO Handle)
, readFontlibAFP :: !(ByteString -> IO [AFP_])
, fontlibPaths :: !([ByteString])
, fontlibSuffix :: !(ByteString)
, cstrlenCheckUDC :: !(CStringLen -> IO ())
, trnToSegments :: FontField -> ByteString -> VarsIO ByteString
, verbose :: !(Bool)
, showHelp :: !(IO ())
} deriving (Typeable)