X-Git-Url: http://gitweb.michael.orlitzky.com/?p=haeredes.git;a=blobdiff_plain;f=src%2FMain.hs;h=a5dc79466067f0dc70fc529169f55d111ae13b96;hp=5c6f401f7a5e839b6f5545bd4e4bba91cd6b3195;hb=689bda2499ec821772b456cb7982527d6740649f;hpb=7cc26ab4bfa90c4abe0c741d5a3eaf575544466a;ds=sidebyside

diff --git a/src/Main.hs b/src/Main.hs
index 5c6f401..a5dc794 100644
--- a/src/Main.hs
+++ b/src/Main.hs
@@ -14,7 +14,7 @@ import Data.String.Utils (join)
 import Network.DNS (
   Domain,
   FileOrNumericHost(RCHostName),
-  ResolvConf(resolvInfo),
+  ResolvConf(resolvInfo, resolvTimeout),
   defaultResolvConf,
   makeResolvSeed,
   withResolver )
@@ -31,25 +31,40 @@ import DNS (
   normalize_case,
   resolve_address )
 import ExitCodes (exit_bad_server)
-
-report :: (Domain, Maybe [Domain]) -> IO ()
-report (d, Nothing) =
+import Timeout (Timeout(..))
+
+
+-- | Given a list of delegates, report results for this
+--   LookupResult.
+--
+--   If there's an empty list in the second component, there were no
+--   query results, so we report that the domain was not delegated. If
+--   there were some results and there are leftovers (after removing
+--   the delegates), we report those as well.
+--
+report :: [Domain] -- ^ The list of @delgts@
+       -> LookupResult
+       -> IO ()
+
+-- If the lookup resulted in a DNS error, we just ignore the whole
+-- thing.
+report _ (_, Left _) = return ()
+
+-- If the lookup succeeded but there were no results, report that the
+-- domain is not delegated.
+report _ (d, Right []) =
   putStrLn $ "Domain " ++ (show d) ++ " not delegated."
-report (d, Just leftovers) =
+
+-- Otherwise, subtract our delegates from the list of results and
+-- report the leftovers.
+report delgts (d, Right hosts) = do
+  let leftovers = hosts \\ delgts
   unless (null leftovers) $
     putStrLn $ "Domain " ++
                (show d) ++
                " delegates somewhere else: " ++
                (join " " (map show leftovers))
 
-clean :: [Domain] -- ^ List of delegates, @ds@
-      -> LookupResult
-      -> LookupResult
-clean _ p@(_, Nothing) = p
-clean delgts (d, Just targets) =
-  (d, Just $ targets \\ delgts)
-
-
 
 main :: IO ()
 main = do
@@ -73,29 +88,35 @@ main = do
   let nrml_domains   = map normalize_function raw_domains
   let nrml_delegates = map normalize_function raw_delegates
 
-  rc <- case (server cfg) of
-          Nothing -> return defaultResolvConf
-          Just s -> do
-            s' <- resolve_address s
-            case s' of
-              Nothing -> do
-                hPutStrLn stderr ("Bad DNS server or lookup error: " ++ s)
-                exitWith (ExitFailure exit_bad_server)
-              Just s'' ->
-                return $ defaultResolvConf { resolvInfo =
-                                               RCHostName (show s'') }
-
+  rc' <- case (server cfg) of
+           Nothing -> return defaultResolvConf
+           Just s -> do
+             s' <- resolve_address s
+             case s' of
+               Left err -> do
+                 let errmsg = show err
+                 hPutStrLn stderr ("Bad DNS server or lookup error: " ++ errmsg)
+                 exitWith (ExitFailure exit_bad_server)
+               Right []  -> do
+                 hPutStrLn stderr ("Hostname " ++ s ++ " has no 'A' records.")
+                 exitWith (ExitFailure exit_bad_server)
+               Right (srv:_) ->
+                 return $ defaultResolvConf { resolvInfo =
+                                                RCHostName (show srv) }
+
+  -- Set the timeout from the command line. The resolvTimeout field is
+  -- in microseconds, so we multiply by one million.
+  let rc = rc' { resolvTimeout = 1000 * 1000 * seconds (timeout cfg) }
   rs <- makeResolvSeed rc
 
   let lookup_function = case cfg of
-                          (NS _ _ _) -> lookupNS'
-                          (MX _ _ _) -> lookupMX'
+                          NS{} -> lookupNS'
+                          MX{} -> lookupMX'
 
   _ <- withResolver rs $ \resolver -> do
          -- Bad stuff happens if we try to run these lookups in parallel
          -- instead of the reports.
          records <- mapM (lookup_function resolver) nrml_domains
-         let cleaned_records = map (clean nrml_delegates) records
-         parallel (map report cleaned_records)
+         parallel (map (report nrml_delegates) records)
 
   stopGlobalPool