(svn r2297) - CodeChange: server-check the next batch of commands.

- CodeChange: since only the server will be able to modify difficulty settings, leave the checking of correct values besides, and trust users will join legit servers.
- CodeChange: for renaming signs, only check if GetDParam(); eg _decode_parameters is empty ('\0') or not, instead of the extra check of players, etc. That basically does the same thing. Also dirty sign two times when renaming, once before, once after the action. Because if the name becomes shorter and you update only after, garbage remains on the screen.
- CodeChange: made GetMaskOfTownActions() available to the town-cmd to double-check if the action was available to the player. For this purpose the hardcoded _local_player has been removed from the function and is now passed as a parameter.

1 files changed, 42 insertions, 29 deletions

diff --git a/roadveh_cmd.c b/roadveh_cmd.c
index 1630d832d..60c59f152 100644
--- a/roadveh_cmd.c
+++ b/roadveh_cmd.c
@@ -105,13 +105,16 @@ void DrawRoadVehEngineInfo(int engine, int x, int y, int maxw)
 	DrawStringMultiCenter(x, y, STR_902A_COST_SPEED_RUNNING_COST, maxw);
 }
 
-int32 EstimateRoadVehCost(byte engine_type)
+int32 EstimateRoadVehCost(EngineID engine_type)
 {
 	return ((_price.roadveh_base >> 3) * RoadVehInfo(engine_type)->base_cost) >> 5;
 }
 
-// p1 = engine_type
-// p2 not used
+/** Build a road vehicle.
+ * @param x,y tile coordinates of depot where road vehicle is built
+ * @param p1 bus/truck type being built (engine)
+ * @param p2 unused
+ */
 int32 CmdBuildRoadVeh(int x, int y, uint32 flags, uint32 p1, uint32 p2)
 {
 	int32 cost;
@@ -125,8 +128,7 @@ int32 CmdBuildRoadVeh(int x, int y, uint32 flags, uint32 p1, uint32 p2)
 	SET_EXPENSES_TYPE(EXPENSES_NEW_VEHICLES);
 
 	cost = EstimateRoadVehCost(p1);
-	if (flags & DC_QUERY_COST)
-		return cost;
+	if (flags & DC_QUERY_COST) return cost;
 
 	/* The ai_new queries the vehicle cost before building the route,
 	 * so we must check against cheaters no sooner than now. --pasky */
@@ -181,7 +183,7 @@ int32 CmdBuildRoadVeh(int x, int y, uint32 flags, uint32 p1, uint32 p2)
 		v->max_speed = rvi->max_speed;
 		v->engine_type = (byte)p1;
 
-		e = &_engines[p1];
+		e = DEREF_ENGINE(p1);
 		v->reliability = e->reliability;
 		v->reliability_spd_dec = e->reliability_spd_dec;
 		v->max_age = e->lifelength * 366;
@@ -202,14 +204,17 @@ int32 CmdBuildRoadVeh(int x, int y, uint32 flags, uint32 p1, uint32 p2)
 		InvalidateWindow(WC_VEHICLE_DEPOT, v->tile);
 		RebuildVehicleLists();
 		InvalidateWindow(WC_COMPANY, v->owner);
+		InvalidateWindow(WC_REPLACE_VEHICLE, VEH_Road); // updates the replace Road window
 	}
 
-	InvalidateWindow(WC_REPLACE_VEHICLE, VEH_Road); // updates the replace Road window
-
 	return cost;
 }
 
-// p1 = vehicle
+/** Start/Stop a road vehicle.
+ * @param x,y unused
+ * @param p1 road vehicle ID to start/stop
+ * @param p2 unused
+ */
 int32 CmdStartStopRoadVeh(int x, int y, uint32 flags, uint32 p1, uint32 p2)
 {
 	Vehicle *v;
@@ -218,8 +223,7 @@ int32 CmdStartStopRoadVeh(int x, int y, uint32 flags, uint32 p1, uint32 p2)
 
 	v = GetVehicle(p1);
 
-	if (v->type != VEH_Road || !CheckOwnership(v->owner))
-		return CMD_ERROR;
+	if (v->type != VEH_Road || !CheckOwnership(v->owner)) return CMD_ERROR;
 
 	if (flags & DC_EXEC) {
 		v->vehstatus ^= VS_STOPPED;
@@ -242,8 +246,11 @@ void ClearSlot(Vehicle *v, RoadStop *rs)
  }
 }
 
-//  p1 = vehicle index in GetVehicle()
-//  p2 not used
+/** Sell a road vehicle.
+ * @param x,y unused
+ * @param p1 vehicle ID to be sold
+ * @param p2 unused
+ */
 int32 CmdSellRoadVeh(int x, int y, uint32 flags, uint32 p1, uint32 p2)
 {
 	Vehicle *v;
@@ -252,8 +259,7 @@ int32 CmdSellRoadVeh(int x, int y, uint32 flags, uint32 p1, uint32 p2)
 
 	v = GetVehicle(p1);
 
-	if (v->type != VEH_Road || !CheckOwnership(v->owner))
-		return CMD_ERROR;
+	if (v->type != VEH_Road || !CheckOwnership(v->owner)) return CMD_ERROR;
 
 	SET_EXPENSES_TYPE(EXPENSES_NEW_VEHICLES);
 
@@ -335,24 +341,29 @@ static Depot *FindClosestRoadDepot(Vehicle *v)
 	}
 }
 
+/** Send a road vehicle to the depot.
+ * @param x,y unused
+ * @param p1 vehicle ID to send to the depot
+ * @param p2 unused
+ */
 int32 CmdSendRoadVehToDepot(int x, int y, uint32 flags, uint32 p1, uint32 p2)
 {
 	Vehicle *v;
-	Depot *depot;
+	const Depot *dep;
 
 	if (!IsVehicleIndex(p1)) return CMD_ERROR;
 
 	v = GetVehicle(p1);
 
-	if (v->type != VEH_Road || !CheckOwnership(v->owner))
-		return CMD_ERROR;
+	if (v->type != VEH_Road || !CheckOwnership(v->owner)) return CMD_ERROR;
 
-	if (v->vehstatus & VS_CRASHED)
-		return CMD_ERROR;
+	if (v->vehstatus & VS_CRASHED) return CMD_ERROR;
 
+	/* If the current orders are already goto-depot */
 	if (v->current_order.type == OT_GOTO_DEPOT) {
 		if (flags & DC_EXEC) {
-
+			/* If the orders to 'goto depot' are in the orders list (forced servicing),
+			 * then skip to the next order; effectively cancelling this forced service */
 			if (HASBIT(v->current_order.flags, OFB_PART_OF_ORDERS))
 				v->cur_order_index++;
 
@@ -363,21 +374,25 @@ int32 CmdSendRoadVehToDepot(int x, int y, uint32 flags, uint32 p1, uint32 p2)
 		return 0;
 	}
 
-	depot = FindClosestRoadDepot(v);
-	if (depot == NULL)
-		return_cmd_error(STR_9019_UNABLE_TO_FIND_LOCAL_DEPOT);
+	dep = FindClosestRoadDepot(v);
+	if (dep == NULL) return_cmd_error(STR_9019_UNABLE_TO_FIND_LOCAL_DEPOT);
 
 	if (flags & DC_EXEC) {
 		v->current_order.type = OT_GOTO_DEPOT;
 		v->current_order.flags = OF_NON_STOP | OF_HALT_IN_DEPOT;
-		v->current_order.station = depot->index;
-		v->dest_tile = depot->xy;
+		v->current_order.station = dep->index;
+		v->dest_tile = dep->xy;
 		InvalidateWindowWidget(WC_VEHICLE_VIEW, v->index, STATUS_BAR);
 	}
 
 	return 0;
 }
 
+/** Turn a roadvehicle around.
+ * @param x,y unused
+ * @param p1 vehicle ID to turn
+ * @param p2 unused
+ */
 int32 CmdTurnRoadVeh(int x, int y, uint32 flags, uint32 p1, uint32 p2)
 {
 	Vehicle *v;
@@ -386,15 +401,13 @@ int32 CmdTurnRoadVeh(int x, int y, uint32 flags, uint32 p1, uint32 p2)
 
 	v = GetVehicle(p1);
 
-	if (v->type != VEH_Road || !CheckOwnership(v->owner))
-		return CMD_ERROR;
+	if (v->type != VEH_Road || !CheckOwnership(v->owner)) return CMD_ERROR;
 
 	if (v->vehstatus & (VS_HIDDEN|VS_STOPPED) ||
 			v->u.road.crashed_ctr != 0 ||
 			v->breakdown_ctr != 0 ||
 			v->u.road.overtaking != 0 ||
 			v->cur_speed < 5) {
-		_error_message = STR_EMPTY;
 		return CMD_ERROR;
 	}