redirect code in place

luprex/cpp/core/world.hpp

@@ -243,10 +243,24 @@ public:
     //
     void disconnected(int64_t actor_id);
 
+    // Notify the world that the front end has implemented a
+    // redirect.  This can return null to indicate a last-minute
+    // failure, in which case the front end must disconnect.
+    //
+    bool redirected(int64_t actor_id, int64_t new_id);
+    
+    // Add a redirect.
+    //
+    void add_redirect(int64_t a, int64_t b) { redirects_.emplace(a,b); }
+    
     // Fetch all redirects and clear the redirects table.
     //
     Redirects fetch_redirects();
 
+    // Return true if there are any redirects.
+    //
+    bool have_redirects() const { return !redirects_.empty(); }
+
     // Probe an arbitrary lua expression.
     //
     // Any print-statements in the lua code are sent into