Data update

Task/Mutex/Ada/mutex-1.adb

@@ -0,0 +1,6 @@
+protected type Mutex is
+   entry Seize;
+   procedure Release;
+private
+   Owned : Boolean := False;
+end Mutex;

Task/Mutex/Ada/mutex-2.adb

@@ -0,0 +1,10 @@
+protected body Mutex is
+   entry Seize when not Owned is
+   begin
+      Owned := True;
+   end Seize;
+   procedure Release is
+   begin
+      Owned := False;
+   end Release;
+end Mutex;

Task/Mutex/Ada/mutex-3.adb

@@ -0,0 +1,15 @@
+declare
+   M : Mutex;
+begin
+   M.Seize;    -- Wait infinitely for the mutex to be free
+   ...         -- Critical code
+   M.Release;  -- Release the mutex
+   ...
+   select
+      M.Seize; -- Wait no longer than 0.5s
+   or delay 0.5;
+      raise Timed_Out;
+   end select;
+   ...         -- Critical code
+   M.Release;  -- Release the mutex
+end;