build paths if we are out of exits on exit session

include/llarp/exit/session.hpp

@@ -20,6 +20,9 @@ namespace llarp
       SelectHop(llarp_nodedb* db, const RouterContact& prev, RouterContact& cur,
                 size_t hop, llarp::path::PathRole roles) override;
 
+      bool
+      ShouldBuildMore(llarp_time_t now) const override;
+
       void
       HandlePathBuilt(llarp::path::Path* p) override;
 

llarp/exit/session.cpp

@@ -19,6 +19,12 @@ namespace llarp
     {
     }
 
+    bool
+    BaseSession::ShouldBuildMore(llarp_time_t now) const
+    {
+      return AvailablePaths(llarp::path::ePathRoleExit) == 0;
+    }
+
     bool
     BaseSession::SelectHop(llarp_nodedb* db, const RouterContact& prev,
                            RouterContact& cur, size_t hop,