doc/examples/ffi/import2.sml

   1 (* main.sml *)
   2
   3 (* Declare ffi to be implemented by calling the C function ffi. *)
   4 val ffi_addr = _address "ffi" public: MLton.Pointer.t;
   5 val ffi_schema = _import * : MLton.Pointer.t -> real array * int * int ref * char ref * int -> char;
   6 open Array
   7
   8 val size = 10
   9 val a = tabulate (size, fn i => real i)
  10 val ri = ref 0
  11 val rc = ref #"0"
  12 val n = 17
  13
  14 (* Call the C function *)
  15 val c = ffi_schema ffi_addr (a, Array.length a, ri, rc, n)
  16
  17 val _ =
  18    print (if c = #"c" andalso !ri = 45 andalso !rc = c
  19              then "success\n"
  20           else "fail\n")
  21
  22 val n = #1 (_symbol "FFI_INT" public: (unit -> int) * (int -> unit);) ()
  23 val _ = print (concat [Int.toString n, "\n"])
  24 val w = #1 (_symbol "FFI_WORD" public: (unit -> word) * (word -> unit);) ()
  25 val _ = print (concat [Word.toString w, "\n"])
  26 val b = #1 (_symbol "FFI_BOOL" public: (unit -> bool) * (bool -> unit);) ()
  27 val _ = print (concat [Bool.toString b, "\n"])
  28 val r = #1 (_symbol "FFI_REAL" public: (unit -> real) * (real -> unit);) ()
  29 val _ = print (concat [Real.toString r, "\n"])
  30
  31 signature OPAQUE =
  32    sig
  33       type t
  34       val toString : t -> string
  35    end
  36
  37 structure OpaqueInt :> OPAQUE =
  38    struct
  39       type t = Int.int
  40       val toString = Int.toString
  41    end
  42 structure OpaqueWord :> OPAQUE =
  43    struct
  44       type t = Word.word
  45       val toString = Word.toString
  46    end
  47 structure OpaqueBool :> OPAQUE =
  48    struct
  49       type t = Bool.bool
  50       val toString = Bool.toString
  51    end
  52 structure OpaqueReal :> OPAQUE =
  53    struct
  54       type t = Real.real
  55       val toString = Real.toString
  56    end
  57
  58 val (n, _) = _symbol "FFI_INT" public: (unit -> OpaqueInt.t) * (OpaqueInt.t -> unit);
  59 val _ = print (concat [OpaqueInt.toString (n ()), "\n"])
  60 val (w, _) = _symbol "FFI_WORD" public: (unit -> OpaqueWord.t) * (OpaqueWord.t -> unit);
  61 val _ = print (concat [OpaqueWord.toString (w ()), "\n"])
  62 val (b, _) = _symbol "FFI_BOOL" public: (unit -> OpaqueBool.t) * (OpaqueBool.t -> unit);
  63 val _ = print (concat [OpaqueBool.toString (b ()), "\n"])
  64 val (r, _) = _symbol "FFI_REAL" public: (unit -> OpaqueReal.t) * (OpaqueReal.t -> unit);
  65 val _ = print (concat [OpaqueReal.toString (r ()), "\n"])
  66
  67 val n_addr = _address "FFI_INT" public: MLton.Pointer.t;
  68 val n = MLton.Pointer.getInt32 (n_addr, 0);
  69 val _ = print (concat [Int.toString n, "\n"])
  70 val w_addr = _address "FFI_WORD" public: MLton.Pointer.t;
  71 val w = MLton.Pointer.getWord32 (w_addr, 0);
  72 val _ = print (concat [Word.toString w, "\n"])
  73 val b_addr = _address "FFI_BOOL" public: MLton.Pointer.t;
  74 val b = (MLton.Pointer.getInt32 (n_addr, 0)) <> 0
  75 val _ = print (concat [Bool.toString b, "\n"])
  76 val r_addr = _address "FFI_REAL" public: MLton.Pointer.t;
  77 val r = MLton.Pointer.getReal64 (r_addr, 0)
  78 val _ = print (concat [Real.toString r, "\n"])