AP_Torqeedo: simplify conversion of master error code into string

libraries/AP_Torqeedo/AP_Torqeedo.cpp

@@ -283,6 +283,50 @@ bool AP_Torqeedo::pre_arm_checks(char *failure_msg, uint8_t failure_msg_len)
     return true;
 }
 
+// returns a human-readable string corresponding the the passed-in
+// master error code (see page 93 of https://media.torqeedo.com/downloads/manuals/torqeedo-Travel-manual-DE-EN.pdf)
+// If no conversion is available then nullptr is returned
+const char * AP_Torqeedo::map_master_error_code_to_string(uint8_t code) const
+{
+    switch (code) {
+    case 2:
+        return "stator high temp";
+    case 5:
+        return "propeller blocked";
+    case 6:
+        return "motor low voltage";
+    case 7:
+        return "motor high current";
+    case 8:
+        return "pcb temp high";
+    case 21:
+        return "tiller cal bad";
+    case 22:
+        return "mag bad";
+    case 23:
+        return "range incorrect";
+    case 30:
+        return "motor comm error";
+    case 32:
+        return "tiller comm error";
+    case 33:
+        return "general comm error";
+    case 41:
+    case 42:
+        return "charge voltage bad";
+    case 43:
+        return "battery flat";
+    case 45:
+        return "battery high current";
+    case 46:
+        return "battery temp error";
+    case 48:
+        return "charging temp error";
+    }
+
+    return nullptr;
+}
+
 // report changes in error codes to user
 void AP_Torqeedo::report_error_codes()
 {
@@ -310,62 +354,19 @@ void AP_Torqeedo::report_error_codes()
         gcs().send_text(MAV_SEVERITY_CRITICAL, "%s batt nearly empty", msg_prefix);
     }
     if (_display_system_state.master_error_code > 0) {
-        char master_err_str_buff[22] = {};
-        switch (_display_system_state.master_error_code) {
-        case 2:
-            strncpy(master_err_str_buff, "stator high temp", ARRAY_SIZE(master_err_str_buff));
-            break;
-        case 5:
-            strncpy(master_err_str_buff, "propeller blocked", ARRAY_SIZE(master_err_str_buff));
-            break;
-        case 6:
-            strncpy(master_err_str_buff, "motor low voltage", ARRAY_SIZE(master_err_str_buff));
-            break;
-        case 7:
-            strncpy(master_err_str_buff, "motor high current", ARRAY_SIZE(master_err_str_buff));
-            break;
-        case 8:
-            strncpy(master_err_str_buff, "pcb temp high", ARRAY_SIZE(master_err_str_buff));
-            break;
-        case 21:
-            strncpy(master_err_str_buff, "tiller cal bad", ARRAY_SIZE(master_err_str_buff));
-            break;
-        case 22:
-            strncpy(master_err_str_buff, "mag bad", ARRAY_SIZE(master_err_str_buff));
-            break;
-        case 23:
-            strncpy(master_err_str_buff, "range incorrect", ARRAY_SIZE(master_err_str_buff));
-            break;
-        case 30:
-            strncpy(master_err_str_buff, "motor comm error", ARRAY_SIZE(master_err_str_buff));
-            break;
-        case 32:
-            strncpy(master_err_str_buff, "tiller comm error", ARRAY_SIZE(master_err_str_buff));
-            break;
-        case 33:
-            strncpy(master_err_str_buff, "general comm error", ARRAY_SIZE(master_err_str_buff));
-            break;
-        case 41:
-        case 42:
-            strncpy(master_err_str_buff, "charge voltage bad", ARRAY_SIZE(master_err_str_buff));
-            break;
-        case 43:
-            strncpy(master_err_str_buff, "battery flat", ARRAY_SIZE(master_err_str_buff));
-            break;
-        case 45:
-            strncpy(master_err_str_buff, "battery high current", ARRAY_SIZE(master_err_str_buff));
-            break;
-        case 46:
-            strncpy(master_err_str_buff, "battery temp error", ARRAY_SIZE(master_err_str_buff));
-            break;
-        case 48:
-            strncpy(master_err_str_buff, "charging temp error", ARRAY_SIZE(master_err_str_buff));
-            break;
-        default:
-            // unknown error code
-            break;
+        const char *error_string = map_master_error_code_to_string(_display_system_state.master_error_code);
+        if (error_string != nullptr) {
+            gcs().send_text(
+                MAV_SEVERITY_CRITICAL, "%s err:%u %s",
+                msg_prefix,
+                _display_system_state.master_error_code,
+                error_string);
+        } else {
+            gcs().send_text(
+                MAV_SEVERITY_CRITICAL, "%s err:%u",
+                msg_prefix,
+                _display_system_state.master_error_code);
         }
-        gcs().send_text(MAV_SEVERITY_CRITICAL, "%s err:%u %s", msg_prefix, _display_system_state.master_error_code, master_err_str_buff);
     }
 
     // report motor status errors

libraries/AP_Torqeedo/AP_Torqeedo.h

@@ -359,6 +359,11 @@ private:
     uint32_t _last_error_report_ms;                             // system time that flag changes were last reported (used to prevent spamming user)
     MotorStatus _motor_status_prev;                             // backup of motor status
     static AP_Torqeedo *_singleton;
+
+    // returns a human-readable string corresponding the the passed-in
+    // master error code (see page 93 of https://media.torqeedo.com/downloads/manuals/torqeedo-Travel-manual-DE-EN.pdf)
+    // If no conversion is available then nullptr is returned
+    const char *map_master_error_code_to_string(uint8_t code) const;
 };
 
 namespace AP {