add common signal_handler for srsUE/srsENB/srsEPC

the signal handler is the same for all three apps. The "running" flag
as well as the file_logger object are in the common header in order
to allow the signal handler to flush the file if the alarm goes off.

lib/include/srslte/common/config_file.h

@@ -25,6 +25,8 @@
 #include "common.h"
 #include <fstream>
 #include <pwd.h>
+#include <sys/types.h>
+#include <unistd.h>
 
 bool config_exists(std::string& filename, std::string default_name)
 {

lib/include/srslte/common/signal_handler.h

@@ -0,0 +1,75 @@
+/*
+ * Copyright 2013-2020 Software Radio Systems Limited
+ *
+ * This file is part of srsLTE.
+ *
+ * srsLTE is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * srsLTE is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * A copy of the GNU Affero General Public License can be found in
+ * the LICENSE file in the top-level directory of this distribution
+ * and at http://www.gnu.org/licenses/.
+ *
+ */
+
+/**
+ * @file signal_handler.h
+ * @brief Common signal handling methods for all srsLTE applications.
+ */
+
+#ifndef SRSLTE_SIGNAL_HANDLER_H
+#define SRSLTE_SIGNAL_HANDLER_H
+
+#include "srslte/common/logger_file.h"
+#include <signal.h>
+#include <stdio.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif // __cplusplus
+
+#define SRSLTE_TERM_TIMEOUT_S (3)
+
+// static vars required by signal handling
+static srslte::logger_file logger_file;
+static bool                running = true;
+
+static void srslte_signal_handler(int signal)
+{
+  switch (signal) {
+    case SIGALRM:
+      fprintf(stderr, "Couldn't stop after %ds. Forcing exit.\n", SRSLTE_TERM_TIMEOUT_S);
+      logger_file.stop();
+      exit(-1);
+    default:
+      // all other registered signals try to stop the app gracefully
+      if (running) {
+        running = false;
+        fprintf(stdout, "Stopping ..\n");
+        alarm(SRSLTE_TERM_TIMEOUT_S);
+      } else {
+        // already waiting for alarm to go off ..
+      }
+      break;
+  }
+}
+
+void srslte_register_signal_handler()
+{
+  signal(SIGINT, srslte_signal_handler);
+  signal(SIGTERM, srslte_signal_handler);
+  signal(SIGHUP, srslte_signal_handler);
+  signal(SIGALRM, srslte_signal_handler);
+}
+
+#ifdef __cplusplus
+}
+#endif // __cplusplus
+#endif // SRSLTE_SIGNAL_HANDLER_H

srsenb/src/main.cc

@@ -27,6 +27,7 @@
 
 #include "srslte/common/config_file.h"
 #include "srslte/common/crash_handler.h"
+#include "srslte/common/signal_handler.h"
 
 #include <boost/program_options.hpp>
 #include <boost/program_options/parsers.hpp>
@@ -340,20 +341,8 @@ void parse_args(all_args_t* args, int argc, char* argv[])
   }
 }
 
-static int  sigcnt     = 0;
-static bool running    = true;
 static bool do_metrics = false;
 
-void sig_int_handler(int signo)
-{
-  sigcnt++;
-  running = false;
-  cout << "Stopping srsENB... Press Ctrl+C " << (10 - sigcnt) << " more times to force stop" << endl;
-  if (sigcnt >= 10) {
-    exit(-1);
-  }
-}
-
 void* input_loop(void* m)
 {
   metrics_stdout* metrics = (metrics_stdout*)m;
@@ -373,7 +362,7 @@ void* input_loop(void* m)
         }
         metrics->toggle_print(do_metrics);
       } else if ('q' == key) {
-        sig_int_handler(0);
+        raise(SIGTERM);
       }
     }
   }
@@ -382,9 +371,7 @@ void* input_loop(void* m)
 
 int main(int argc, char* argv[])
 {
-  signal(SIGINT, sig_int_handler);
+  srslte_register_signal_handler();
-  signal(SIGTERM, sig_int_handler);
-  signal(SIGHUP, sig_int_handler);
   all_args_t                         args = {};
   srslte::metrics_hub<enb_metrics_t> metricshub;
   metrics_stdout                     metrics_screen;
@@ -395,7 +382,6 @@ int main(int argc, char* argv[])
   parse_args(&args, argc, argv);
 
   srslte::logger_stdout logger_stdout;
-  srslte::logger_file   logger_file;
 
   // Set logger
   srslte::logger* logger = nullptr;

srsepc/src/main.cc

@@ -26,6 +26,7 @@
 #include "srslte/common/bcd_helpers.h"
 #include "srslte/common/config_file.h"
 #include "srslte/common/crash_handler.h"
+#include "srslte/common/signal_handler.h"
 #include <boost/program_options.hpp>
 #include <iostream>
 #include <signal.h>
@@ -34,13 +35,6 @@ using namespace std;
 using namespace srsepc;
 namespace bpo = boost::program_options;
 
-bool running = true;
-
-void sig_int_handler(int signo)
-{
-  running = false;
-}
-
 typedef struct {
   std::string nas_level;
   int         nas_hex_limit;
@@ -380,9 +374,7 @@ std::string get_build_string()
 
 int main(int argc, char* argv[])
 {
-  signal(SIGINT, sig_int_handler);
+  srslte_register_signal_handler();
-  signal(SIGTERM, sig_int_handler);
-  signal(SIGHUP, sig_int_handler);
 
   // print build info
   cout << endl << get_build_string() << endl;
@@ -394,7 +386,6 @@ int main(int argc, char* argv[])
   parse_args(&args, argc, argv);
 
   srslte::logger_stdout logger_stdout;
-  srslte::logger_file   logger_file;
   srslte::logger*       logger;
 
   /*Init logger*/

srsue/src/main.cc

@@ -19,27 +19,24 @@
  *
  */
 
-#include <pthread.h>
-#include <signal.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <unistd.h>
-
-#include <boost/program_options.hpp>
-#include <boost/program_options/parsers.hpp>
-#include <fstream>
-#include <iostream>
-#include <string>
-
 #include "srslte/common/config_file.h"
 #include "srslte/common/crash_handler.h"
 #include "srslte/common/logmap.h"
 #include "srslte/common/metrics_hub.h"
+#include "srslte/common/signal_handler.h"
 #include "srslte/srslte.h"
 #include "srslte/version.h"
 #include "srsue/hdr/metrics_csv.h"
 #include "srsue/hdr/metrics_stdout.h"
 #include "srsue/hdr/ue.h"
+#include <boost/program_options.hpp>
+#include <boost/program_options/parsers.hpp>
+#include <iostream>
+#include <pthread.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string>
+#include <unistd.h>
 
 extern bool simulate_rlf;
 
@@ -51,10 +48,6 @@ namespace bpo = boost::program_options;
  *  Local static variables
  ***********************************************************************/
 
-#define UE_STOP_TIMEOUT_S (3)
-
-static srslte::logger_file logger_file;
-static bool                running        = true;
 static bool                do_metrics     = false;
 static metrics_stdout*     metrics_screen = nullptr;
 
@@ -550,22 +543,6 @@ static int parse_args(all_args_t* args, int argc, char* argv[])
   return SRSLTE_SUCCESS;
 }
 
-static void sig_handler(int signal)
-{
-  switch (signal) {
-    case SIGALRM:
-      fprintf(stderr, "Couldn't stop after %ds. Forcing exit.\n", UE_STOP_TIMEOUT_S);
-      logger_file.stop();
-      exit(-1);
-    default:
-      // all other registered signal try to stop UE gracefully
-      running = false;
-      cout << "Stopping srsUE ..." << endl;
-      alarm(UE_STOP_TIMEOUT_S);
-      break;
-  }
-}
-
 static void* input_loop(void*)
 {
   string key;
@@ -599,10 +576,7 @@ static void* input_loop(void*)
 
 int main(int argc, char* argv[])
 {
-  signal(SIGINT, sig_handler);
+  srslte_register_signal_handler();
-  signal(SIGTERM, sig_handler);
-  signal(SIGHUP, sig_handler);
-  signal(SIGALRM, sig_handler);
   srslte_debug_handle_crash(argc, argv);
 
   all_args_t args = {};