client: ensure worker is joined on close()

src/client.cpp

@@ -378,6 +378,11 @@ void Context::Pvt::close()
             conn->cleanup();
         }
     });
+
+    tcp_loop.join();
+
+    // ensure any in-progress callbacks have completed
+    manager.sync();
 }
 
 void Context::Pvt::poke()

src/evhelper.cpp

@@ -99,6 +99,11 @@ struct evbase::Pvt : public epicsThreadRunable
     }
 
     virtual ~Pvt() {
+        join();
+    }
+
+    void join()
+    {
         if(event_base_loopexit(base.get(), nullptr))
             log_crit_printf(logerr, "evbase error while interrupting loop for %p\n", base.get());
         worker.exitWait();
@@ -189,6 +194,11 @@ evbase::evbase(const std::string &name, unsigned prio)
 
 evbase::~evbase() {}
 
+void evbase::join()
+{
+    pvt->join();
+}
+
 void evbase::sync()
 {
     call([](){});

src/evhelper.h

@@ -62,7 +62,7 @@ struct owned_ptr : public std::unique_ptr<T>
 struct PVXS_API evbase {
     explicit evbase(const std::string& name, unsigned prio=0);
     ~evbase();
-    void start();
+    void join();
 
     void sync();