src/HOL/Tools/Sledgehammer/async_manager.ML
changeset 41042 8275f52ac991
parent 40301 bf39a257b3d3
child 43005 c96f06bffd90
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/HOL/Tools/Sledgehammer/async_manager.ML	Tue Dec 07 09:58:56 2010 +0100
@@ -0,0 +1,237 @@
+(*  Title:      HOL/Tools/Sledgehammer/async_manager.ML
+    Author:     Fabian Immler, TU Muenchen
+    Author:     Makarius
+    Author:     Jasmin Blanchette, TU Muenchen
+
+Central manager for asynchronous diagnosis tool threads.
+*)
+
+signature ASYNC_MANAGER =
+sig
+  val break_into_chunks : string list -> string list
+  val launch :
+    string -> Time.time -> Time.time -> string -> (unit -> string) -> unit
+  val kill_threads : string -> string -> unit
+  val running_threads : string -> string -> unit
+  val thread_messages : string -> string -> int option -> unit
+end;
+
+structure Async_Manager : ASYNC_MANAGER =
+struct
+
+(** preferences **)
+
+val message_store_limit = 20;
+val message_display_limit = 5;
+
+
+(** thread management **)
+
+(* data structures over threads *)
+
+structure Thread_Heap = Heap
+(
+  type elem = Time.time * Thread.thread;
+  fun ord ((a, _), (b, _)) = Time.compare (a, b);
+);
+
+fun lookup_thread xs = AList.lookup Thread.equal xs;
+fun delete_thread xs = AList.delete Thread.equal xs;
+fun update_thread xs = AList.update Thread.equal xs;
+
+
+(* state of thread manager *)
+
+type state =
+  {manager: Thread.thread option,
+   timeout_heap: Thread_Heap.T,
+   active: (Thread.thread * (string * Time.time * Time.time * string)) list,
+   canceling: (Thread.thread * (string * Time.time * string)) list,
+   messages: (string * string) list,
+   store: (string * string) list}
+
+fun make_state manager timeout_heap active canceling messages store : state =
+  {manager = manager, timeout_heap = timeout_heap, active = active,
+   canceling = canceling, messages = messages, store = store}
+
+val global_state = Synchronized.var "async_manager"
+  (make_state NONE Thread_Heap.empty [] [] [] []);
+
+
+(* unregister thread *)
+
+fun unregister message thread =
+  Synchronized.change global_state
+  (fn state as {manager, timeout_heap, active, canceling, messages, store} =>
+    (case lookup_thread active thread of
+      SOME (tool, _, _, desc) =>
+        let
+          val active' = delete_thread thread active;
+          val now = Time.now ()
+          val canceling' = (thread, (tool, now, desc)) :: canceling
+          val message' = desc ^ "\n" ^ message
+          val messages' = (tool, message') :: messages;
+          val store' = (tool, message') ::
+            (if length store <= message_store_limit then store
+             else #1 (chop message_store_limit store));
+        in make_state manager timeout_heap active' canceling' messages' store' end
+    | NONE => state));
+
+
+(* main manager thread -- only one may exist *)
+
+val min_wait_time = seconds 0.3;
+val max_wait_time = seconds 10.0;
+
+fun replace_all bef aft =
+  let
+    fun aux seen "" = String.implode (rev seen)
+      | aux seen s =
+        if String.isPrefix bef s then
+          aux seen "" ^ aft ^ aux [] (unprefix bef s)
+        else
+          aux (String.sub (s, 0) :: seen) (String.extract (s, 1, NONE))
+  in aux [] end
+
+(* This is a workaround for Proof General's off-by-a-few sendback display bug,
+   whereby "pr" in "proof" is not highlighted. *)
+val break_into_chunks = maps (space_explode "\000" o replace_all "\n\n" "\000")
+
+fun print_new_messages () =
+  case Synchronized.change_result global_state
+         (fn {manager, timeout_heap, active, canceling, messages, store} =>
+             (messages, make_state manager timeout_heap active canceling []
+                                   store)) of
+    [] => ()
+  | msgs as (tool, _) :: _ =>
+    let val ss = break_into_chunks (map snd msgs) in
+      List.app Output.urgent_message (tool ^ ": " ^ hd ss :: tl ss)
+    end
+
+fun check_thread_manager () = Synchronized.change global_state
+  (fn state as {manager, timeout_heap, active, canceling, messages, store} =>
+    if (case manager of SOME thread => Thread.isActive thread | NONE => false) then state
+    else let val manager = SOME (Toplevel.thread false (fn () =>
+      let
+        fun time_limit timeout_heap =
+          (case try Thread_Heap.min timeout_heap of
+            NONE => Time.+ (Time.now (), max_wait_time)
+          | SOME (time, _) => time);
+
+        (*action: find threads whose timeout is reached, and interrupt canceling threads*)
+        fun action {manager, timeout_heap, active, canceling, messages, store} =
+          let val (timeout_threads, timeout_heap') =
+            Thread_Heap.upto (Time.now (), Thread.self ()) timeout_heap;
+          in
+            if null timeout_threads andalso null canceling then
+              NONE
+            else
+              let
+                val _ = List.app (Simple_Thread.interrupt o #1) canceling
+                val canceling' = filter (Thread.isActive o #1) canceling
+                val state' = make_state manager timeout_heap' active canceling' messages store;
+              in SOME (map #2 timeout_threads, state') end
+          end;
+      in
+        while Synchronized.change_result global_state
+          (fn state as {timeout_heap, active, canceling, messages, store, ...} =>
+            if null active andalso null canceling andalso null messages
+            then (false, make_state NONE timeout_heap active canceling messages store)
+            else (true, state))
+        do
+          (Synchronized.timed_access global_state (SOME o time_limit o #timeout_heap) action
+            |> these
+            |> List.app (unregister "Timed out.\n");
+            print_new_messages ();
+            (*give threads some time to respond to interrupt*)
+            OS.Process.sleep min_wait_time)
+      end))
+    in make_state manager timeout_heap active canceling messages store end)
+
+
+(* register thread *)
+
+fun register tool birth_time death_time desc thread =
+ (Synchronized.change global_state
+    (fn {manager, timeout_heap, active, canceling, messages, store} =>
+      let
+        val timeout_heap' = Thread_Heap.insert (death_time, thread) timeout_heap;
+        val active' = update_thread (thread, (tool, birth_time, death_time, desc)) active;
+        val state' = make_state manager timeout_heap' active' canceling messages store;
+      in state' end);
+  check_thread_manager ())
+
+
+fun launch tool birth_time death_time desc f =
+  (Toplevel.thread true
+       (fn () =>
+           let
+             val self = Thread.self ()
+             val _ = register tool birth_time death_time desc self
+             val message = f ()
+           in unregister message self end);
+   ())
+
+
+(** user commands **)
+
+(* kill threads *)
+
+fun kill_threads tool workers = Synchronized.change global_state
+  (fn {manager, timeout_heap, active, canceling, messages, store} =>
+    let
+      val killing =
+        map_filter (fn (th, (tool', _, _, desc)) =>
+                       if tool' = tool then SOME (th, (tool', Time.now (), desc))
+                       else NONE) active
+      val state' = make_state manager timeout_heap [] (killing @ canceling) messages store;
+      val _ = if null killing then () else Output.urgent_message ("Killed active " ^ workers ^ ".")
+    in state' end);
+
+
+(* running threads *)
+
+fun seconds time = string_of_int (Time.toSeconds time) ^ " s"
+
+fun running_threads tool workers =
+  let
+    val {active, canceling, ...} = Synchronized.value global_state;
+
+    val now = Time.now ();
+    fun running_info (_, (tool', birth_time, death_time, desc)) =
+      if tool' = tool then
+        SOME ("Running: " ^ seconds (Time.- (now, birth_time)) ^ " -- " ^
+              seconds (Time.- (death_time, now)) ^ " to live:\n" ^ desc)
+      else
+        NONE
+    fun canceling_info (_, (tool', death_time, desc)) =
+      if tool' = tool then
+        SOME ("Trying to interrupt thread since " ^
+              seconds (Time.- (now, death_time)) ^ ":\n" ^ desc)
+      else
+        NONE
+    val running =
+      case map_filter running_info active of
+        [] => ["No " ^ workers ^ " running."]
+      | ss => "Running " ^ workers ^ ":" :: ss
+    val interrupting =
+      case map_filter canceling_info canceling of
+        [] => []
+      | ss => "Trying to interrupt the following " ^ workers ^ ":" :: ss
+  in Output.urgent_message (space_implode "\n\n" (running @ interrupting)) end
+
+fun thread_messages tool worker opt_limit =
+  let
+    val limit = the_default message_display_limit opt_limit;
+    val tool_store = Synchronized.value global_state
+                     |> #store |> filter (curry (op =) tool o fst)
+    val header =
+      "Recent " ^ worker ^ " messages" ^
+        (if length tool_store <= limit then ":"
+         else " (" ^ string_of_int limit ^ " displayed):");
+  in
+    List.app Output.urgent_message (header :: break_into_chunks
+                                     (map snd (#1 (chop limit tool_store))))
+  end
+
+end;