diff --git a/src/vehicle_cmd.cpp b/src/vehicle_cmd.cpp
--- a/src/vehicle_cmd.cpp
+++ b/src/vehicle_cmd.cpp
@@ -72,7 +72,7 @@ CommandCost CmdBuildRoadVehicle(TileInde
 CommandCost CmdBuildShip       (TileIndex tile, DoCommandFlag flags, const Engine *e, uint16 data, Vehicle **v);
 CommandCost CmdBuildAircraft   (TileIndex tile, DoCommandFlag flags, const Engine *e, uint16 data, Vehicle **v);
 
-CommandCost CmdRefitVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text);
+CommandCost CmdRefitVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const std::string &text);
 
 /**
  * Build a vehicle.
@@ -86,7 +86,7 @@ CommandCost CmdRefitVehicle(TileIndex ti
  * @param text unused
  * @return the cost of this operation or an error
  */
-CommandCost CmdBuildVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
+CommandCost CmdBuildVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const std::string &text)
 {
 	/* Elementary check for valid location. */
 	if (!IsDepotTile(tile) || !IsTileOwner(tile, _current_company)) return CMD_ERROR;
@@ -154,7 +154,7 @@ CommandCost CmdBuildVehicle(TileIndex ti
 
 		if (refitting) {
 			/* Refit only one vehicle. If we purchased an engine, it may have gained free wagons. */
-			value.AddCost(CmdRefitVehicle(tile, flags, v->index, cargo | (1 << 16), nullptr));
+			value.AddCost(CmdRefitVehicle(tile, flags, v->index, cargo | (1 << 16), {}));
 		} else {
 			/* Fill in non-refitted capacities */
 			_returned_refit_capacity = e->GetDisplayDefaultCapacity(&_returned_mail_refit_capacity);
@@ -206,7 +206,7 @@ CommandCost CmdSellRailWagon(DoCommandFl
  * @param text unused.
  * @return the cost of this operation or an error.
  */
-CommandCost CmdSellVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
+CommandCost CmdSellVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const std::string &text)
 {
 	Vehicle *v = Vehicle::GetIfValid(GB(p1, 0, 20));
 	if (v == nullptr) return CMD_ERROR;
@@ -468,7 +468,7 @@ static CommandCost RefitVehicle(Vehicle 
  * @param text unused
  * @return the cost of this operation or an error
  */
-CommandCost CmdRefitVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
+CommandCost CmdRefitVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const std::string &text)
 {
 	Vehicle *v = Vehicle::GetIfValid(p1);
 	if (v == nullptr) return CMD_ERROR;
@@ -556,7 +556,7 @@ CommandCost CmdRefitVehicle(TileIndex ti
  * @param text unused
  * @return the cost of this operation or an error
  */
-CommandCost CmdStartStopVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
+CommandCost CmdStartStopVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const std::string &text)
 {
 	/* Disable the effect of p2 bit 0, when DC_AUTOREPLACE is not set */
 	if ((flags & DC_AUTOREPLACE) == 0) SetBit(p2, 0);
@@ -640,7 +640,7 @@ CommandCost CmdStartStopVehicle(TileInde
  * @param text unused
  * @return the cost of this operation or an error
  */
-CommandCost CmdMassStartStopVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
+CommandCost CmdMassStartStopVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const std::string &text)
 {
 	VehicleList list;
 	bool do_start = HasBit(p1, 0);
@@ -680,7 +680,7 @@ CommandCost CmdMassStartStopVehicle(Tile
  * @param text unused
  * @return the cost of this operation or an error
  */
-CommandCost CmdDepotSellAllVehicles(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
+CommandCost CmdDepotSellAllVehicles(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const std::string &text)
 {
 	VehicleList list;
 
@@ -718,7 +718,7 @@ CommandCost CmdDepotSellAllVehicles(Tile
  * @param text unused
  * @return the cost of this operation or an error
  */
-CommandCost CmdDepotMassAutoReplace(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
+CommandCost CmdDepotMassAutoReplace(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const std::string &text)
 {
 	VehicleList list;
 	CommandCost cost = CommandCost(EXPENSES_NEW_VEHICLES);
@@ -822,7 +822,7 @@ static void CloneVehicleName(const Vehic
  * @param text unused
  * @return the cost of this operation or an error
  */
-CommandCost CmdCloneVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
+CommandCost CmdCloneVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const std::string &text)
 {
 	CommandCost total_cost(EXPENSES_NEW_VEHICLES);
 
@@ -1044,7 +1044,7 @@ static CommandCost SendAllVehiclesToDepo
  * @param text unused
  * @return the cost of this operation or an error
  */
-CommandCost CmdSendVehicleToDepot(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
+CommandCost CmdSendVehicleToDepot(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const std::string &text)
 {
 	if (p1 & DEPOT_MASS_SEND) {
 		/* Mass goto depot requested */
@@ -1069,7 +1069,7 @@ CommandCost CmdSendVehicleToDepot(TileIn
  * @param text the new name or an empty string when resetting to the default
  * @return the cost of this operation or an error
  */
-CommandCost CmdRenameVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
+CommandCost CmdRenameVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const std::string &text)
 {
 	Vehicle *v = Vehicle::GetIfValid(p1);
 	if (v == nullptr || !v->IsPrimaryVehicle()) return CMD_ERROR;
@@ -1077,7 +1077,7 @@ CommandCost CmdRenameVehicle(TileIndex t
 	CommandCost ret = CheckOwnership(v->owner);
 	if (ret.Failed()) return ret;
 
-	bool reset = StrEmpty(text);
+	bool reset = text.empty();
 
 	if (!reset) {
 		if (Utf8StringLength(text) >= MAX_LENGTH_VEHICLE_NAME_CHARS) return CMD_ERROR;
@@ -1110,7 +1110,7 @@ CommandCost CmdRenameVehicle(TileIndex t
  * @param text unused
  * @return the cost of this operation or an error
  */
-CommandCost CmdChangeServiceInt(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
+CommandCost CmdChangeServiceInt(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const std::string &text)
 {
 	Vehicle *v = Vehicle::GetIfValid(p1);
 	if (v == nullptr || !v->IsPrimaryVehicle()) return CMD_ERROR;