Fix #7188: check the validity of command callback for scripts (#7701)

src/script/api/script_object.cpp

@@ -83,6 +83,23 @@ ScriptObject::ActiveInstance::~ActiveInstance()
 	return GetStorage()->mode_instance;
 }
 
+/* static */ void ScriptObject::SetLastCommand(TileIndex tile, uint32 p1, uint32 p2, uint32 cmd)
+{
+	GetStorage()->last_tile = tile;
+	GetStorage()->last_p1 = p1;
+	GetStorage()->last_p2 = p2;
+	GetStorage()->last_cmd = cmd;
+}
+
+/* static */ bool ScriptObject::CheckLastCommand(TileIndex tile, uint32 p1, uint32 p2, uint32 cmd)
+{
+	if (GetStorage()->last_tile != tile) return false;
+	if (GetStorage()->last_p1 != p1) return false;
+	if (GetStorage()->last_p2 != p2) return false;
+	if (GetStorage()->last_cmd != cmd) return false;
+	return true;
+}
+
 /* static */ void ScriptObject::SetDoCommandCosts(Money value)
 {
 	GetStorage()->costs = CommandCost(value);
@@ -304,6 +321,9 @@ ScriptObject::ActiveInstance::~ActiveInstance()
 	/* Only set p2 when the command does not come from the network. */
 	if (GetCommandFlags(cmd) & CMD_CLIENT_ID && p2 == 0) p2 = UINT32_MAX;
 
+	/* Store the command for command callback validation. */
+	if (!estimate_only && _networking && !_generating_world) SetLastCommand(tile, p1, p2, cmd);
+
 	/* Try to perform the command. */
 	CommandCost res = ::DoCommandPInternal(tile, p1, p2, cmd, (_networking && !_generating_world) ? ScriptObject::GetActiveInstance()->GetDoCommandCallback() : nullptr, text, false, estimate_only);
 

src/script/api/script_object.hpp

@@ -73,6 +73,16 @@ protected:
 	 */
 	static bool DoCommand(TileIndex tile, uint32 p1, uint32 p2, uint cmd, const char *text = nullptr, Script_SuspendCallbackProc *callback = nullptr);
 
+	/**
+	 * Store the latest command executed by the script.
+	 */
+	static void SetLastCommand(TileIndex tile, uint32 p1, uint32 p2, uint cmd);
+
+	/**
+	 * Check if it's the latest command executed by the script.
+	 */
+	static bool CheckLastCommand(TileIndex tile, uint32 p1, uint32 p2, uint cmd);
+
 	/**
 	 * Sets the DoCommand costs counter to a value.
 	 */

src/script/script_instance.cpp

@@ -680,10 +680,12 @@ SQInteger ScriptInstance::GetOpsTillSuspend()
 	return this->engine->GetOpsTillSuspend();
 }
 
-void ScriptInstance::DoCommandCallback(const CommandCost &result, TileIndex tile, uint32 p1, uint32 p2)
+bool ScriptInstance::DoCommandCallback(const CommandCost &result, TileIndex tile, uint32 p1, uint32 p2, uint32 cmd)
 {
 	ScriptObject::ActiveInstance active(this);
 
+	if (!ScriptObject::CheckLastCommand(tile, p1, p2, cmd)) return false;
+
 	ScriptObject::SetLastCommandRes(result.Succeeded());
 
 	if (result.Failed()) {
@@ -692,6 +694,10 @@ void ScriptInstance::DoCommandCallback(const CommandCost &result, TileIndex tile
 		ScriptObject::IncreaseDoCommandCosts(result.GetCost());
 		ScriptObject::SetLastCost(result.GetCost());
 	}
+
+	ScriptObject::SetLastCommand(INVALID_TILE, 0, 0, CMD_END);
+
+	return true;
 }
 
 void ScriptInstance::InsertEvent(class ScriptEvent *event)

src/script/script_instance.hpp

@@ -182,8 +182,10 @@ public:
 	 * @param tile The tile on which the command was executed.
 	 * @param p1 p1 as given to DoCommandPInternal.
 	 * @param p2 p2 as given to DoCommandPInternal.
+	 * @param cmd cmd as given to DoCommandPInternal.
+	 * @return true if we handled result.
 	 */
-	void DoCommandCallback(const CommandCost &result, TileIndex tile, uint32 p1, uint32 p2);
+	bool DoCommandCallback(const CommandCost &result, TileIndex tile, uint32 p1, uint32 p2, uint32 cmd);
 
 	/**
 	 * Insert an event for this script.

src/script/script_storage.hpp

@@ -46,6 +46,11 @@ private:
 	uint last_error;                 ///< The last error of the command.
 	bool last_command_res;           ///< The last result of the command.
 
+	TileIndex last_tile;             ///< The last tile passed to a command.
+	uint32 last_p1;                  ///< The last p1 passed to a command.
+	uint32 last_p2;                  ///< The last p2 passed to a command.
+	uint32 last_cmd;                 ///< The last cmd passed to a command.
+
 	VehicleID new_vehicle_id;        ///< The ID of the new Vehicle.
 	SignID new_sign_id;              ///< The ID of the new Sign.
 	GroupID new_group_id;            ///< The ID of the new Group.
@@ -73,6 +78,10 @@ public:
 		last_cost         (0),
 		last_error        (STR_NULL),
 		last_command_res  (true),
+		last_tile         (INVALID_TILE),
+		last_p1           (0),
+		last_p2           (0),
+		last_cmd          (CMD_END),
 		new_vehicle_id    (0),
 		new_sign_id       (0),
 		new_group_id      (0),