RTI exit while saving the trace file

core/federated/RTI/rti.c

@@ -47,41 +47,62 @@ THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "rti_lib.h"
-unsigned int _lf_number_of_workers = 0u;
+#include <signal.h>     // To trap ctrl-c and invoke a clean stop to save the trace file, if needed.
 
 extern RTI_instance_t _RTI;
 
+/**
+ * The tracing mechanism uses the number of workers variable `_lf_number_of_workers`.
+ * For RTI tracing, the number of workers is set as the number of federates.
+ */
+unsigned int _lf_number_of_workers = 0u;
+
 /**
  * RTI trace file name
  */
 const char *rti_trace_file_name = "rti.lft";
 
+/**
+ * @brief A clean termination of the RTI will write the trace file, if tracing is
+ * enabled, before exiting.
+ */
+void termination() {
+    if (_RTI.tracing_enabled) {
+        stop_trace();
+        lf_print("RTI trace file saved.");
+    }   
+    lf_print("RTI is exiting.");
+}
+
 int main(int argc, const char* argv[]) {
 
     lf_mutex_init(&rti_mutex);
     lf_cond_init(&received_start_times, &rti_mutex);
     lf_cond_init(&sent_start_time, &rti_mutex);
 
+    // Catch the Ctrl-C signal, for a clean exit that does not lose the trace information
+    signal(SIGINT, exit);
+    if (atexit(termination) != 0) {
+        lf_print_warning("Failed to register termination function!");
+    }
+
     if (!process_args(argc, argv)) {
         // Processing command-line arguments failed.
         return -1;
     }
     if (_RTI.tracing_enabled) {
         _lf_number_of_workers = _RTI.number_of_federates;
         start_trace(rti_trace_file_name);
-        printf("Tracing the RTI execution in %s file.\n", rti_trace_file_name);
+        lf_print("Tracing the RTI execution in %s file.", rti_trace_file_name);
     }
-    printf("Starting RTI for %d federates in federation ID %s\n", _RTI.number_of_federates, _RTI.federation_id);
+    lf_print("Starting RTI for %d federates in federation ID %s.", _RTI.number_of_federates, _RTI.federation_id);
     assert(_RTI.number_of_federates < UINT16_MAX);
     _RTI.federates = (federate_t*)calloc(_RTI.number_of_federates, sizeof(federate_t));
     for (uint16_t i = 0; i < _RTI.number_of_federates; i++) {
         initialize_federate(i);
     }
     int socket_descriptor = start_rti_server(_RTI.user_specified_port);
     wait_for_federates(socket_descriptor);
-    if (_RTI.tracing_enabled) {
-        stop_trace();
-    }
-    printf("RTI is exiting.\n");
+
     return 0;
 }