Initial implementation of bindist comparison tool

[ghc-hetmet.git] / distrib / compare / Tar.hs

diff --git a/distrib/compare/Tar.hs b/distrib/compare/Tar.hs
new file mode 100644 (file)
index 0000000..50b238a
--- /dev/null
+++ b/distrib/compare/Tar.hs
@@ -0,0 +1,58 @@
+
+module Tar where
+
+import Data.Either
+import Data.List
+import System.Exit
+import System.Process
+
+import Utils
+
+readTarLines :: FilePath -> IO [TarLine]
+readTarLines fp
+ = do (ec, out, err) <- readProcessWithExitCode "tar" ["-jtvf", fp] ""
+      case (ec, err) of
+          (ExitSuccess, []) ->
+                  case parseTarLines fp out of
+                  Left  errs -> die errs
+                  Right tls  -> return tls
+          _ ->
+              die ["Failed running tar -jtvf " ++ show fp,
+                   "Exit code: " ++ show ec,
+                   "Stderr: " ++ show err]
+
+parseTarLines :: FilePath -> String -> Either Errors [TarLine]
+parseTarLines fp xs
+    = case partitionEithers (zipWith (parseTarLine fp) [1..] (lines xs)) of
+      ([],    tls) -> Right tls
+      (errss, _)   -> Left (intercalate [""] errss)
+
+data TarLine = TarLine {
+                   tlPermissions :: String,
+                   tlUser :: String,
+                   tlGroup :: String,
+                   tlSize :: Integer,
+                   tlDateTime :: String,
+                   tlFileName :: FilePath
+               }
+
+parseTarLine :: FilePath -> Int -> String -> Either Errors TarLine
+parseTarLine fp line str
+ = case re "^([^ ]+) ([^ ]+)/([^ ]+) +([0-9]+) ([^ ]+ [^ ]+) ([^ ]+)$"
+           str of
+   Just [perms, user, grp, sizeStr, dateTime, filename] ->
+       case maybeRead sizeStr of
+       Just size ->
+           Right $ TarLine {
+                       tlPermissions = perms,
+                       tlUser        = user,
+                       tlGroup       = grp,
+                       tlSize        = size,
+                       tlDateTime    = dateTime,
+                       tlFileName    = filename
+                   }
+       _ -> error "Can't happen: Can't parse size"
+   _ ->
+       Left ["In " ++ show fp ++ ", at line " ++ show line,
+             "Tar line doesn't parse: " ++ show str]
+