Fix M17 callsign management

Now a default callsign "OPNRTX" is used in M17 mode, and when the user
sets its own callsign in the settings menu, that one is correctly used
instead. Add initialization to RTX data structure.

openrtx/src/rtx/OpMode_M17.cpp

@@ -77,9 +77,9 @@ void OpMode_M17::update(rtxStatus_t *const status, const bool newCfg)
             audio_enableMic();
             radio_enableTx();
 
-            // TODO: Allow destinations different than broadcast
-            std::string source_address("OPNRTX");
-            m17Tx.start(source_address);
+            std::string source_address(status->source_address);
+            std::string destination_address(status->destination_address);
+            m17Tx.start(source_address, destination_address);
 
             status->opStatus = TX;
         }

openrtx/src/rtx/rtx.cpp

@@ -27,7 +27,7 @@
 pthread_mutex_t *cfgMutex;      // Mutex for incoming config messages
 
 const rtxStatus_t *newCnf;      // Pointer for incoming config messages
-rtxStatus_t rtxStatus;      // RTX driver status
+rtxStatus_t rtxStatus = { 0 };  // RTX driver status
 
 float rssi;                     // Current RSSI in dBm
 bool  reinitFilter;             // Flag for RSSI filter re-initialisation

openrtx/src/state.c

@@ -82,6 +82,9 @@ void state_init()
 
     state.emergency = false;
 
+    // Initialize M17_data
+    strncpy(state.m17_data.callsign, "OPNRTX", 10);
+
     // Read settings from flash memory
     // NOTE: Disable reading VFO from flash until persistence is implemented
     //int valid = nvm_readSettings(&state.settings);

openrtx/src/threads.c

@@ -103,6 +103,10 @@ void *ui_task(void *arg)
             rtx_cfg.txTone = ctcss_tone[state.channel.fm.txTone];
             pthread_mutex_unlock(&rtx_mutex);
 
+            // Copy new M17 source and destination addresses
+            strncpy(rtx_cfg.source_address, state.m17_data.callsign, 10);
+            strncpy(rtx_cfg.destination_address, "", 10);
+
             rtx_configure(&rtx_cfg);
             sync_rtx = false;
         }

openrtx/src/ui/ui.c

@@ -1324,8 +1324,9 @@ void ui_updateFSM(event_t event, bool *sync_rtx)
                     {
                         _ui_textInputConfirm(ui_state.new_callsign);
                         // Save selected callsign and disable input mode
-                        strcpy(state.m17_data.callsign, ui_state.new_callsign);
+                        strncpy(state.m17_data.callsign, ui_state.new_callsign, 10);
                         ui_state.edit_mode = false;
+                        *sync_rtx = true;
                     }
                     else if(msg.keys & KEY_ESC)
                         // Discard selected callsign and disable input mode