1 files changed, 135 insertions, 0 deletions
diff --git a/src/GF/Infra/ReadFiles.hs b/src/GF/Infra/ReadFiles.hs
new file mode 100644
index 000000000..f755397f2
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+++ b/src/GF/Infra/ReadFiles.hs
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+module ReadFiles where
+
+import Arch (selectLater, modifiedFiles, ModTime)
+
+import Operations
+import UseIO
+import System
+import Char
+import Monad
+
+-- make analysis for GF grammar modules. AR 11/6/2003
+
+-- to find all files that have to be read, put them in dependency order, and
+-- decide which files need recompilation. Name file.gf is returned for them,
+-- and file.gfc or file.gfr otherwise.
+
+type ModName = String
+type FileName = String
+type InitPath = String
+type FullPath = String
+
+getAllFiles :: [InitPath] -> [(FullPath,ModTime)] -> FileName -> 
+               IOE [FullPath]
+getAllFiles ps env file = do
+  ds  <- getImports ps file
+  -- print ds  ---- debug
+  ds1 <- ioeErr $ either 
+           return 
+           (\ms -> Bad $ "circular modules" +++ unwords (map show (head ms))) $ 
+              topoTest $ map fst ds
+  let paths = [(f,p) | ((f,_),p) <- ds]
+  let pds1 = [(p,f) | f <- ds1, Just p <- [lookup f paths]]
+  ds2 <- ioeIO $ mapM selectFormat pds1
+  -- print ds2 ---- debug
+  let ds3 = needCompile ds ds2
+  ds4 <- ioeIO $ modifiedFiles env ds3
+  return ds4
+
+getImports :: [InitPath] -> FileName -> IOE [((ModName,[ModName]),InitPath)]
+getImports ps = get [] where
+  get ds file = do
+    let name = fileBody file
+    (p,s) <- readFileIfPath ps $ file
+    let imps  = importsOfFile s
+    case imps of
+      _ | elem name (map (fst . fst) ds) -> return ds  --- file already read
+      [] -> return $ ((name,[]),p):ds
+      _  -> do
+        let files = map gfFile imps
+        foldM get (((name,imps),p):ds) files
+
+-- to decide whether to read gf or gfc; returns full file path
+
+selectFormat :: (InitPath,ModName) -> IO (ModName,(FullPath,Bool))
+selectFormat (p,f) = do
+  let pf = prefixPathName p f
+  f0 <- selectLater (gfFile pf) (gfcFile pf)
+  f1 <- selectLater (gfrFile pf) f0
+  return $ (f, (f1, f1 == gfFile pf)) -- True if needs compile
+
+needCompile :: [((ModName,[ModName]),InitPath)] -> [(ModName,(FullPath,Bool))] ->
+               [FullPath]
+needCompile deps sfiles = filt $ mark $ iter changed where
+
+  -- start with the changed files themselves; returns [ModName]
+  changed = [f | (f,(_,True)) <- sfiles] 
+
+  -- add other files that depend on some changed file; returns [ModName]
+  iter np = let new = [f | ((f,fs),_) <- deps, 
+                           not (elem f np), any (flip elem np) fs]
+            in  if null new then np else (iter (new ++ np))
+
+  -- for each module in the full list, choose source file if change is needed
+  -- returns [FullPath]
+  mark cs = [f' | (f,(file,_)) <- sfiles, 
+                  let f' = if (elem f cs) then gfFile (fileBody file) else file]
+
+  -- if the top file is gfc, only gfc files need be read (could be even better)---
+  filt ds = if isGFC (last ds) 
+    then [gfcFile name | f <- ds, 
+               let (name,suff) = nameAndSuffix f, elem suff ["gfc","gfr"]] 
+    else ds
+
+isGFC = (== "gfc") . fileSuffix
+
+gfcFile = suffixFile "gfc"
+gfrFile = suffixFile "gfr"
+gfFile  = suffixFile "gf"
+
+-- to get imports without parsing the file
+
+importsOfFile :: String -> [FilePath]
+importsOfFile = 
+  filter (not . spec) .      -- ignore keywords and special symbols
+  unqual .                   -- take away qualifiers
+  takeWhile (not . term) .   -- read until curly or semic
+  drop 2 .                   -- ignore keyword and module name
+  lexs .                     -- analyse into lexical tokens
+  unComm                     -- ignore comments before the headed line
+ where
+    term = flip elem ["{",";"]
+    spec = flip elem ["of", "open","in", "reuse", "=", "(", ")",",","**"]
+    unqual ws = case ws of
+      "(":q:ws' -> unqual ws'
+      w:ws' -> w:unqual ws'
+      _ -> ws
+
+unComm s = case s of
+      '-':'-':cs -> unComm $ dropWhile (/='\n') cs
+      '{':'-':cs -> dpComm cs
+      c:cs -> c : unComm cs
+      _ -> s
+    
+dpComm s = case s of
+      '-':'}':cs -> unComm cs
+      c:cs -> dpComm cs
+      _ -> s
+    
+lexs s = x:xs where 
+      (x,y) = head $ lex s
+      xs = if null y then [] else lexs y
+
+-- old GF tolerated newlines in quotes. No more supported!
+fixNewlines s = case s of
+     '"':cs -> '"':mk cs
+     c  :cs -> c:fixNewlines cs
+     _ -> s
+ where
+   mk s = case s of
+     '\\':'"':cs -> '\\':'"': mk cs
+     '"'     :cs -> '"' :fixNewlines cs
+     '\n'    :cs -> '\\':'n': mk cs
+     c       :cs -> c : mk cs
+     _ -> s 
+