iox-eclipse-iceoryx#1030 De-register signal handler at the end of mai…

…n in examples to prevent access to deinitialized resources

iceoryx_examples/icediscovery/iox_wait_for_service.cpp

@@ -122,5 +122,9 @@ int main()
                   << std::endl;
     }
 
+    // de-register signal handler before destroying the Discovery
+    signal(SIGINT, SIG_DFL);
+    signal(SIGTERM, SIG_DFL);
+
     return (EXIT_SUCCESS);
 }

iceoryx_examples/request_response/client_cxx_waitset.cpp

@@ -49,11 +49,6 @@ void signalHandler(int)
 
 int main()
 {
-    auto sigTermGuard =
-        iox::posix::registerSignalHandler(iox::posix::Signal::TERM, signalHandler).expect("failed to register SIGTERM");
-    auto sigIntGuard =
-        iox::posix::registerSignalHandler(iox::posix::Signal::INT, signalHandler).expect("failed to register SIGINT");
-
     //! [initialize runtime]
     iox::runtime::PoshRuntime::initRuntime(APP_NAME);
     //! [initialize runtime]
@@ -63,6 +58,12 @@ int main()
     //! [create waitset]
     waitset.emplace();
 
+    // since the waitset is used in signal handler, this must happen after the waitset initialization
+    auto sigTermGuard =
+        iox::posix::registerSignalHandler(iox::posix::Signal::TERM, signalHandler).expect("failed to register SIGTERM");
+    auto sigIntGuard =
+        iox::posix::registerSignalHandler(iox::posix::Signal::INT, signalHandler).expect("failed to register SIGINT");
+
     //! [create client]
     iox::popo::ClientOptions options;
     options.responseQueueCapacity = 2U;
@@ -131,6 +132,10 @@ int main()
     }
     //! [mainloop]
 
+    // de-register signal handler before destroying the waitset
+    signal(SIGINT, SIG_DFL);
+    signal(SIGTERM, SIG_DFL);
+
     waitset.reset();
     std::cout << "shutting down" << std::endl;
 

iceoryx_examples/request_response_in_c/client_c_waitset.c

@@ -49,9 +49,6 @@ void sigHandler(int signalValue)
 
 int main(void)
 {
-    signal(SIGINT, sigHandler);
-    signal(SIGTERM, sigHandler);
-
     iox_runtime_init(APP_NAME);
 
     iox_client_storage_t clientStorage;
@@ -72,6 +69,10 @@ int main(void)
     }
     //! [create waitset and attach client]
 
+    // since the waitset is used in signal handler, this must happen after the waitset initialization
+    signal(SIGINT, sigHandler);
+    signal(SIGTERM, sigHandler);
+
     while (keepRunning)
     {
         struct AddRequest* request = NULL;
@@ -145,6 +146,9 @@ int main(void)
     }
 
     //! [cleanup]
+    signal(SIGINT, SIG_DFL);
+    signal(SIGTERM, SIG_DFL);
+
     iox_ws_detach_client_state(waitset, client, ClientState_HAS_RESPONSE);
     iox_ws_deinit(waitset);
     iox_client_deinit(client);

iceoryx_examples/waitset/ice_waitset_basic.cpp

@@ -96,6 +96,10 @@ int main()
 
     std::cout << "shutting down" << std::endl;
 
+    // de-register signal handler before destroying the waitset
+    signal(SIGINT, SIG_DFL);
+    signal(SIGTERM, SIG_DFL);
+
     waitset.reset();
     return (EXIT_SUCCESS);
 }

iceoryx_examples/waitset_in_c/ice_c_waitset_gateway.c

@@ -151,6 +151,9 @@ int main(void)
     //! [event loop]
 
     //! [cleanup all resources]
+    signal(SIGINT, SIG_DFL);
+    signal(SIGTERM, SIG_DFL);
+
     for (uint64_t i = 0U; i < NUMBER_OF_SUBSCRIBERS; ++i)
     {
         // not mandatory since iox_sub_deinit will detach the subscriber automatically

iceoryx_examples/waitset_in_c/ice_c_waitset_grouping.c

@@ -144,6 +144,9 @@ int main(void)
     //! [event loop]
 
     //! [cleanup all resources]
+    signal(SIGINT, SIG_DFL);
+    signal(SIGTERM, SIG_DFL);
+
     for (uint64_t i = 0U; i < NUMBER_OF_SUBSCRIBERS; ++i)
     {
         iox_sub_deinit(subscriber[i]);

iceoryx_examples/waitset_in_c/ice_c_waitset_individual.c

@@ -130,6 +130,9 @@ int main(void)
     //! [event loop]
 
     //! [cleanup all resources]
+    signal(SIGINT, SIG_DFL);
+    signal(SIGTERM, SIG_DFL);
+
     for (uint64_t i = 0U; i < NUMBER_OF_SUBSCRIBERS; ++i)
     {
         iox_sub_deinit(subscriber[i]);

iceoryx_examples/waitset_in_c/ice_c_waitset_timer_driven_execution.c

@@ -156,6 +156,9 @@ int main(void)
     //! [event loop]
 
     //! [cleanup all resources]
+    signal(SIGINT, SIG_DFL);
+    signal(SIGTERM, SIG_DFL);
+
     joinThread(cyclicTriggerThread);
     iox_ws_deinit(waitSet);
     iox_user_trigger_deinit(shutdownTrigger);