[Listener] Fix config parsing memory leaks

The configuration parsing function could call exit() (e.g. with -h, -V,
or in case of error), implying a memory leak. This is fixed.
Additionally, minor cleaning in the configuration functions.

owlps-listener/owlps-listener.h

@@ -164,14 +164,14 @@ enum {MODE_ACTIVE = 'a', MODE_PASSIVE = 'p', MODE_MIXED = 'm'} ;
 
 
 /* Function headers */
-void initialise_configuration(int argc, char **argv) ;
-void parse_config_file(int argc, char **argv) ;
-void parse_command_line(int argc, char **argv) ;
-void parse_main_options(int argc, char **argv) ;
+int initialise_configuration(int argc, char **argv) ;
+int parse_config_file(int argc, char **argv) ;
+int parse_command_line(int argc, char **argv) ;
+int parse_main_options(int argc, char **argv) ;
 #ifdef USE_PTHREAD
-void parse_calibration_data(int argc, char **argv) ;
+int parse_calibration_data(int argc, char **argv) ;
 #endif // USE_PTHREAD
-void check_configuration(void) ;
+int check_configuration(void) ;
 #ifdef DEBUG
 void print_configuration(void) ;
 #endif // DEBUG

owlps-listener/owlps-listenerd.c

@@ -50,7 +50,7 @@ owl_bool coordinates_provided = owl_false ;
 #endif // USE_PTHREAD
 
 #ifdef USE_CONFIG_FILE
-cfg_t *cfg ; // Configuration structure
+cfg_t *cfg = NULL ; // Configuration structure
 
 #else // USE_CONFIG_FILE
 /* If we do not use libconfuse, we declare a structure to store getopt
@@ -119,11 +119,13 @@ int main(int argc, char *argv[])
     autocalibration_hello_thread ;
 #endif // USE_PTHREAD
 
-  program_name = argv[0] ;
-  initialise_configuration(argc, argv) ;
-
   owl_run = owl_true ;
 
+  program_name = argv[0] ;
+  ret = initialise_configuration(argc, argv) ;
+  if (! owl_run)
+    goto exit ;
+
   /* Set up signal handlers */
   action.sa_flags = 0 ;
   sigemptyset(&action.sa_mask) ;
@@ -245,19 +247,38 @@ int main(int argc, char *argv[])
 
 
 
-void initialise_configuration(int argc, char **argv)
+/*
+ * Read the configuration from both the command line and the
+ * configuration file.
+ * Returns an error code, or 0 in case of success. If the program should
+ * stop (because of a special option or a configuration error), owl_run
+ * is set to false.
+ */
+int initialise_configuration(int argc, char **argv)
 {
-  parse_config_file(argc, argv) ;
-  parse_command_line(argc, argv) ;
-  check_configuration() ;
+  int ret ;
+
+  ret = parse_config_file(argc, argv) ;
+  if (! owl_run)
+    return ret ;
+
+  ret = parse_command_line(argc, argv) ;
+  if (! owl_run)
+    return ret ;
+
+  ret = check_configuration() ;
+  if (! owl_run)
+    return ret ;
 
   if (VERBOSE_INFO)
     print_configuration() ;
+
+  return 0 ;
 }
 
 
 
-void parse_config_file(int argc, char **argv)
+int parse_config_file(int argc, char **argv)
 {
 #ifdef USE_CONFIG_FILE
   // If we use libconfuse, we declare options:
@@ -343,10 +364,12 @@ void parse_config_file(int argc, char **argv)
           break ;
         case 'h' :
           print_usage() ;
-          exit(0) ;
+          owl_run = owl_false ;
+          return EXIT_SUCCESS ;
         case 'V' :
           print_version() ;
-          exit(0) ;
+          owl_run = owl_false ;
+          return EXIT_SUCCESS ;
         }
     }
 
@@ -373,25 +396,37 @@ void parse_config_file(int argc, char **argv)
               "Error! Parsing of configuration file « %s » failed!\n",
               config_file) ;
       free(config_file) ;
-      exit(ERR_PARSING_CONFIG_FILE) ;
+      owl_run = owl_false ;
+      return ERR_PARSING_CONFIG_FILE ;
     }
   free(config_file) ;
 #endif // USE_CONFIG_FILE
+
+  return 0 ;
 }
 
 
 
-void parse_command_line(int argc, char **argv)
+int parse_command_line(int argc, char **argv)
 {
-  parse_main_options(argc, argv) ;
+  int ret ;
+
+  ret = parse_main_options(argc, argv) ;
+  if (! owl_run)
+    return ret ;
+
 #ifdef USE_PTHREAD
-  parse_calibration_data(argc, argv) ;
+  ret = parse_calibration_data(argc, argv) ;
+  if (! owl_run)
+    return ret ;
 #endif // USE_PTHREAD
+
+  return 0 ;
 }
 
 
 
-void parse_main_options(int argc, char **argv)
+int parse_main_options(int argc, char **argv)
 {
   int opt ;
 
@@ -430,8 +465,6 @@ void parse_main_options(int argc, char **argv)
           break ;
         case 'f' : // Config file
           break ; // (already parsed)
-        case 'h' : // Usage
-          break ; // (already parsed)
         case 'H' :
 #ifdef USE_PTHREAD
           SET_AUTOCALIBRATION_HELLO_DELAY(strtol(optarg, NULL, 0)) ;
@@ -483,22 +516,23 @@ void parse_main_options(int argc, char **argv)
         case 'v' :
           INCREMENT_VERBOSE() ;
           break ;
-        case 'V' : // Version
-          break ; // (already parsed)
         case 'w' :
           SET_WIFI_IFACE(optarg) ;
           break ;
         default :
           print_usage() ;
-          exit(ERR_BAD_USAGE) ;
+          owl_run = owl_false ;
+          return ERR_BAD_USAGE ;
         }
     }
+
+  return 0 ;
 }
 
 
 
 #ifdef USE_PTHREAD
-void parse_calibration_data(int argc, char **argv)
+int parse_calibration_data(int argc, char **argv)
 {
   /* Parse remaining arguments (possible calibration data) */
   if (argc - optind != 0)
@@ -514,15 +548,18 @@ void parse_calibration_data(int argc, char **argv)
       else // Bad number of arguments
         {
           print_usage() ;
-          exit(ERR_BAD_USAGE) ;
+          owl_run = owl_false ;
+          return ERR_BAD_USAGE ;
         }
     }
+
+  return 0 ;
 }
 #endif // USE_PTHREAD
 
 
 
-void check_configuration()
+int check_configuration()
 {
   switch (GET_MODE())
     {
@@ -533,7 +570,8 @@ void check_configuration()
     default :
       fprintf(stderr, "Error! Unknown mode « %c ».\n", (char) GET_MODE()) ;
       print_usage() ;
-      exit(ERR_BAD_USAGE) ;
+      owl_run = owl_false ;
+      return ERR_BAD_USAGE ;
     }
 
   if (GET_RTAP_IFACE()[0] == '\0')
@@ -541,7 +579,8 @@ void check_configuration()
       fprintf(stderr, "Error! You must specify a radiotap interface"
               " for the capture.\n") ;
       print_usage() ;
-      exit(ERR_BAD_USAGE) ;
+      owl_run = owl_false ;
+      return ERR_BAD_USAGE ;
     }
 
   if (GET_WIFI_IFACE()[0] == '\0')
@@ -611,6 +650,8 @@ void check_configuration()
         }
     }
 #endif // USE_PTHREAD
+
+  return 0 ;
 }