epoll_helper: use std::atomic to protect exit called from different thread

lib/include/srsran/common/epoll_helper.h

@@ -17,6 +17,7 @@
 #ifndef SRSRAN_EPOLL_HELPER_H
 #define SRSRAN_EPOLL_HELPER_H
 
+#include <atomic>
 #include <functional>
 #include <signal.h>
 #include <sys/epoll.h>
@@ -58,7 +59,7 @@ private:
 class epoll_signal_handler : public epoll_handler
 {
 public:
-  epoll_signal_handler(bool* running_) : running(running_) {}
+  epoll_signal_handler(std::atomic<bool>& running_) : running(running_) {}
 
   int handle_event(int fd, epoll_event e, int epoll_fd)
   {
@@ -72,7 +73,7 @@ public:
       case SIGINT:
       case SIGHUP:
       case SIGQUIT:
-        *running = false;
+        running = false;
         break;
       default:
         fprintf(stderr, "got signal %d\n", info.ssi_signo);
@@ -82,7 +83,7 @@ public:
   }
 
 private:
-  bool* running = nullptr;
+  std::atomic<bool>& running;
 };
 
 ///< Create periodic epoll timer every 1ms

srsue/test/ttcn3/hdr/ttcn3_syssim.h

@@ -25,6 +25,7 @@
 #include "ttcn3_sys_interface.h"
 #include "ttcn3_ue.h"
 #include "ttcn3_ut_interface.h"
+#include <atomic>
 #include <functional>
 
 class ttcn3_syssim : public syssim_interface_phy,
@@ -224,7 +225,7 @@ private:
 
   // Simulator vars
   ttcn3_ue*         ue      = nullptr;
-  bool      running = false;
+  std::atomic<bool> running = {false};
 
   typedef enum { UE_SWITCH_ON = 0, UE_SWITCH_OFF, ENABLE_DATA, DISABLE_DATA } ss_events_t;
   block_queue<ss_events_t> event_queue;

srsue/test/ttcn3/src/ttcn3_syssim.cc

@@ -49,7 +49,7 @@ ttcn3_syssim::ttcn3_syssim(ttcn3_ue* ue_) :
   mac_msg_dl(20, ss_mac_logger),
   pdus(logger),
   ue(ue_),
-  signal_handler(&running),
+  signal_handler(running),
   timer_handler(create_tti_timer(), [&](uint64_t res) { new_tti_indication(res); })
 {
   if (ue->init(all_args_t{}, this, "INIT_TEST") != SRSRAN_SUCCESS) {