util.sml

   1 structure Util :> UTIL =
   2 struct
   3
   4 datatype 'a flat_element =
   5          BEGIN
   6        | END
   7        | ITEM of 'a
   8 type 'a flat_tree = 'a flat_element list
   9
  10 fun printInt n =
  11     Web.print (if n < 0 then
  12                    "-" ^ Int.toString (~n)
  13                else
  14                    Int.toString n)
  15
  16 fun printReal n =
  17     Web.print (if n < 0.0 then
  18                    "-" ^ Real.fmt (StringCvt.FIX (SOME 2)) (~n)
  19                else
  20                    Real.fmt (StringCvt.FIX (SOME 2)) n)
  21
  22 fun id x = x
  23
  24 fun makeSet f items =
  25     case items of
  26         [] => "()"
  27       | [usr] => "(" ^ f usr ^ ")"
  28       | usr::rest => foldl (fn (usr, s) => s ^ ", " ^ f usr) ("(" ^ f usr) rest ^ ")"
  29
  30 fun neg (r : real) = ~r
  31 fun add (r1 : real, r2) = r1 + r2
  32
  33 fun isIdent ch = Char.isLower ch orelse Char.isDigit ch
  34
  35 fun validHost s =
  36     size s > 0 andalso size s < 20 andalso List.all isIdent (String.explode s)
  37
  38 fun validDomain s =
  39     size s > 0 andalso size s < 100 andalso List.all validHost (String.fields (fn ch => ch = #".") s)
  40
  41 fun validUser s =
  42     size s > 0 andalso size s < 50 andalso List.all
  43                                                (fn ch => isIdent ch orelse ch = #"." orelse ch = #"_" orelse ch = #"-" orelse ch = #"+")
  44                                                (String.explode s)
  45
  46 fun validEmailUser s =
  47     size s > 0 andalso size s < 50 andalso List.all
  48                                                (fn ch => Char.isAlphaNum ch orelse ch = #"." orelse ch = #"_" orelse ch = #"-" orelse ch = #"+")
  49                                                (String.explode s)
  50
  51 fun validEmail s =
  52     (case String.fields (fn ch => ch = #"@") s of
  53          [user, host] => validEmailUser user andalso validDomain host
  54        | _ => false)
  55
  56 fun whoisUrl dom = String.concat ["http://reports.internic.net/cgi/whois?whois_nic=", dom, "&type=domain"]
  57
  58 val rnd = ref (Random.rand (0, 0))
  59
  60 fun init () = rnd := Random.rand (SysWord.toInt (Posix.Process.pidToWord (Posix.ProcEnv.getpid ())),
  61                                   SysWord.toInt (Posix.Process.pidToWord (Posix.ProcEnv.getpid ())))
  62
  63 fun randomPassword () = Int.toString (Int.abs (Random.randInt (!rnd)))
  64
  65 fun domainDir dom =
  66     String.concatWith "/" ("/etc/domains" :: String.fields (fn ch => ch = #".") dom)
  67
  68 end