Add an IP address parser to enable specifying multiple clients in the Monitor block configuration

src/core/receiver/gnss_flowgraph.cc

@@ -1157,11 +1157,10 @@ void GNSSFlowgraph::init()
 	 */
     enable_monitor_ = configuration_->property("Monitor.enable_monitor", false);
 
-    std::vector<std::string> udp_addr_vec;
-
     std::string address_string = configuration_->property("Monitor.client_addresses", std::string("127.0.0.1"));
-    //todo: split the string in substrings using the separator and fill the address vector.
+    std::vector<std::string> udp_addr_vec = split_string(address_string, '_');
-    udp_addr_vec.push_back(address_string);
+    std::sort(udp_addr_vec.begin(), udp_addr_vec.end());
+    udp_addr_vec.erase(std::unique(udp_addr_vec.begin(), udp_addr_vec.end()), udp_addr_vec.end());
 
     if (enable_monitor_)
         {
@@ -1599,3 +1598,17 @@ Gnss_Signal GNSSFlowgraph::search_next_signal(std::string searched_signal, bool
         }
     return result;
 }
+
+std::vector<std::string> GNSSFlowgraph::split_string(const std::string &s, char delim)
+{
+    std::vector<std::string> v;
+    std::stringstream ss(s);
+    std::string item;
+
+    while (std::getline(ss, item, delim))
+    {
+        *(std::back_inserter(v)++) = item;
+    }
+
+    return v;
+}

src/core/receiver/gnss_flowgraph.h

@@ -186,6 +186,7 @@ private:
 
     bool enable_monitor_;
     gr::basic_block_sptr GnssSynchroMonitor_;
+    std::vector<std::string> split_string(const std::string &s, char delim);
 };
 
 #endif /*GNSS_SDR_GNSS_FLOWGRAPH_H_*/