Putzing around with vmail

[hcoop/domtool2.git] / src / mail / vmail.sml

diff --git a/src/mail/vmail.sml b/src/mail/vmail.sml
index 60a3a35..cf36f9f 100644 (file)
--- a/src/mail/vmail.sml
+++ b/src/mail/vmail.sml
@@ -28,33 +28,41 @@ datatype listing =
 
 fun list domain =
     let
-       val inf = TextIO.openIn (OS.Path.joinDirFile {dir = Config.Courier.userdbDir,
-                                                     file = domain})
-
-       fun loop users =
-           case TextIO.inputLine inf of
-               NONE => Listing (rev users)
-             | SOME line =>
-               case String.tokens Char.isSpace line of
-                   [addr, fields] =>
-                   (case String.fields (fn ch => ch = #"@") addr of
-                        [user, _] =>
-                        let
-                            fun parseFields fields =
-                                case fields of
-                                    "mail" :: mailbox :: _ => loop ({user = user, mailbox = mailbox} :: users)
-                                  | _ :: _ :: rest => parseFields rest
-                                  | _ => Error "Invalid fields in database"
-                        in
-                            parseFields (String.fields (fn ch => ch = #"|" orelse ch = #"=") fields)
-                        end
-                      | _ => Error "Invalid e-mail address format in database")
-                 | _ => Error "Invalid entry in database"
+       val file = OS.Path.joinDirFile {dir = Config.Courier.userdbDir,
+                                                     file = domain}
     in
-       loop []
-       before TextIO.closeIn inf
+       if Posix.FileSys.access (file, []) then
+           let
+               val inf = TextIO.openIn file
+
+               fun loop users =
+                   case TextIO.inputLine inf of
+                       NONE => Listing (rev users)
+                     | SOME line =>
+                       case String.tokens Char.isSpace line of
+                           [addr, fields] =>
+                           (case String.fields (fn ch => ch = #"@") addr of
+                                [user, _] =>
+                                let
+                                    fun parseFields fields =
+                                        case fields of
+                                            "mail" :: mailbox :: _ => loop ({user = user, mailbox = mailbox} :: users)
+                                          | _ :: _ :: rest => parseFields rest
+                                          | _ => Error "Invalid fields in database"
+                                in
+                                    parseFields (String.fields (fn ch => ch = #"|" orelse ch = #"=") fields)
+                                end
+                              | _ => Error "Invalid e-mail address format in database")
+                         | _ => Error "Invalid entry in database"
+           in
+               loop []
+               before TextIO.closeIn inf
+           end
+       else
+           Listing []
     end
-       handle IO.Io _ => Listing []
+    handle IO.Io {name, function, ...} =>
+          Error ("IO failure: " ^ name ^ ": " ^ function)
 
 fun mailboxExists {domain, user} =
     let