- Incapsulate code so that the hack we previously used in CPUPoliciesGatekeeper isn't needed anymore

- Now CPUPolicy has a callback method for scripting languages, but it is up to derived classes to take
mutexes and set the value when needed (maybe we can improve this?)


git-svn-id: svn://svn.gna.org/svn/sgpemv2/trunk@862 3ecf2c5c-341e-0410-92b4-d18e462d057c

src/backend/cpu_policies_gatekeeper.cc

@@ -118,25 +118,11 @@ CPUPoliciesGatekeeper::activate_policy(History *history, CPUPolicy* policy) thro
   
   try
   {
-    // policy->activate() needs already an active policy, because:
-    //   * it calls the configure() method on the 
-    //     insert-your-favourite-scripting-language-here-policy
-    //   * which in turn calls the configure() method in the 
-    //     code written by the user
-    //   * which probably uses Simulation to get the _active_ C++ policy,
-    //     so it can get its policy_parameters()
-    //  ... so **DON'T** play Mr. Clever Dick and swap the following two
-    //    lines in an optimization frenzy! Or the user policy WILL fail.
-    _active_policies[history] = policy;
     policy->activate();
+    _active_policies[history] = policy;
   }
   catch(const CPUPolicyException& e)
-  {
-    //std::cerr << e.what() << std::endl;
-    // See the comment above to understand why we do this
-    // in this way
-    _active_policies.erase(_active_policies.find(history));
-    
+  {    
     // the caller need to know if it failed
     throw;
   }

src/backend/cpu_policy.cc

@@ -22,6 +22,11 @@
 using namespace std;
 using namespace sgpem;
 
+
+// Static member data
+CPUPolicy*  CPUPolicy::_callback_policy = NULL;
+
+
 CPUPolicy::~CPUPolicy()
 {}
 
@@ -31,3 +36,20 @@ CPUPolicy::get_parameters()
 {
   return _parameters;
 }
+
+
+
+CPUPolicy* 
+CPUPolicy::callback_get_policy() throw(std::runtime_error)
+{
+  if(_callback_policy == NULL)
+    throw std::runtime_error("CPUPolicy::callback_get_policy() not used as a callback method. NULL ptr returned.");
+  return _callback_policy;
+}
+
+
+void
+CPUPolicy::set_callback_policy(CPUPolicy* ptr)
+{
+  _callback_policy = ptr;
+}

src/backend/cpu_policy.hh

@@ -30,6 +30,8 @@
 #include "user_interrupt_exception.hh"
 #include "malformed_policy_exception.hh"
 
+#include <stdexcept>
+
 namespace sgpem
 {
   class CPUPolicy;
@@ -102,8 +104,18 @@ namespace sgpem
      */
     PolicyParameters& get_parameters();
 
+    /** This method is used only as a callback by scripting languages */
+    static CPUPolicy* callback_get_policy() throw(std::runtime_error);
+    
   protected:
-    PolicyParameters _parameters;
+    PolicyParameters            _parameters;
+
+    static void       set_callback_policy(CPUPolicy* ptr = NULL);
+
+  private:
+    // Used by callback_get_policy:
+    static CPUPolicy*     _callback_policy;
+
   };
 
 }//~ namespace sgpem