Working Well in MP

tools/java/BaseVehicleConstraintPatch.java

@@ -21,6 +21,7 @@ import org.objectweb.asm.tree.VarInsnNode;
  */
 public final class BaseVehicleConstraintPatch {
     private static final String TARGET_NAME = "addPointConstraint";
+    private static final String UPDATE_NAME = "update";
     private static final String CONSTRAINT_CHANGED_NAME = "constraintChanged";
     private static final String AUTHORIZATION_CHANGED_NAME = "authorizationChanged";
     private static final String AUTHORIZATION_CLIENT_COLLIDE_NAME = "authorizationClientCollide";
@@ -49,6 +50,9 @@ public final class BaseVehicleConstraintPatch {
     private static final String BULLET_ADD_POINT = "addPointConstraint";
     private static final String BULLET_ADD_ROPE_DESC = "(IIFFFFFFF)I";
     private static final String BULLET_ADD_POINT_DESC = "(IIFFFFFF)I";
+    private static final String CAR_CONTROLLER_OWNER = "zombie/core/physics/CarController";
+    private static final String CAR_CONTROLLER_PARK = "park";
+    private static final String CAR_CONTROLLER_PARK_DESC = "()V";
     private static final String GET_DRIVER_DESC = "()Lzombie/characters/IsoGameCharacter;";
     private static final String HELPER_OWNER = "zombie/vehicles/LandtrainConstraintAuthHelper";
     private static final String HELPER_METHOD = "resolveConstraintDriver";
@@ -75,6 +79,9 @@ public final class BaseVehicleConstraintPatch {
             "authorizationServerOnSeatLandtrain";
     private static final String HELPER_AUTHORIZATION_SERVER_ON_SEAT_DESC =
             "(Lzombie/vehicles/BaseVehicle;Lzombie/characters/IsoPlayer;Z)V";
+    private static final String HELPER_SAFE_PARK = "safeParkControllerLandtrain";
+    private static final String HELPER_SAFE_PARK_DESC =
+            "(Lzombie/core/physics/CarController;)V";
 
     private static final class AddPointPatchStats {
         int removedBreakCalls;
@@ -107,6 +114,7 @@ public final class BaseVehicleConstraintPatch {
         int patchedAuthorizationClientCollideMethods = 0;
         int patchedAuthorizationServerCollideMethods = 0;
         int patchedAuthorizationServerOnSeatMethods = 0;
+        int patchedSafeParkCalls = 0;
 
         for (MethodNode method : classNode.methods) {
             if (TARGET_NAME.equals(method.name) && isTargetAddPointConstraint(method.desc)) {
@@ -114,6 +122,8 @@ public final class BaseVehicleConstraintPatch {
                 AddPointPatchStats stats = patchAddPointConstraint(method);
                 removedCalls += stats.removedBreakCalls;
                 forcedRigidCalls += stats.forcedRigidCalls;
+            } else if (UPDATE_NAME.equals(method.name) && VOID_NOARG_DESC.equals(method.desc)) {
+                patchedSafeParkCalls += patchNullSafeParkCalls(method);
             } else if (CONSTRAINT_CHANGED_NAME.equals(method.name)
                     && VOID_NOARG_DESC.equals(method.desc)) {
                 patchedConstraintDriverCalls += patchConstraintChangedDriverCalls(method);
@@ -198,6 +208,11 @@ public final class BaseVehicleConstraintPatch {
                     "Expected to patch authorizationServerOnSeat, patched "
                             + patchedAuthorizationServerOnSeatMethods);
         }
+        if (patchedSafeParkCalls < 1) {
+            throw new IllegalStateException(
+                    "Expected to patch at least 1 CarController.park call, patched "
+                            + patchedSafeParkCalls);
+        }
         if (patchedEnterBlockedCalls < 1) {
             throw new IllegalStateException(
                     "Expected to patch isEnterBlocked call, patched " + patchedEnterBlockedCalls);
@@ -230,6 +245,8 @@ public final class BaseVehicleConstraintPatch {
                         + patchedAuthorizationServerCollideMethods
                         + "/"
                         + patchedAuthorizationServerOnSeatMethods
+                        + ", safe park hooks: "
+                        + patchedSafeParkCalls
                         + ", enter-block hooks: "
                         + patchedEnterBlockedCalls
                         + "/"
@@ -318,6 +335,36 @@ public final class BaseVehicleConstraintPatch {
         return patched;
     }
 
+    private static int patchNullSafeParkCalls(MethodNode method) {
+        int patched = 0;
+        InsnList insns = method.instructions;
+        for (AbstractInsnNode node = insns.getFirst(); node != null; ) {
+            AbstractInsnNode next = node.getNext();
+            if (!(node instanceof MethodInsnNode call)) {
+                node = next;
+                continue;
+            }
+            if (!CAR_CONTROLLER_OWNER.equals(call.owner)
+                    || !CAR_CONTROLLER_PARK.equals(call.name)
+                    || !CAR_CONTROLLER_PARK_DESC.equals(call.desc)) {
+                node = next;
+                continue;
+            }
+
+            MethodInsnNode replacement =
+                    new MethodInsnNode(
+                            Opcodes.INVOKESTATIC,
+                            HELPER_OWNER,
+                            HELPER_SAFE_PARK,
+                            HELPER_SAFE_PARK_DESC,
+                            false);
+            insns.set(call, replacement);
+            patched++;
+            node = next;
+        }
+        return patched;
+    }
+
     private static int patchMethodDelegateToHelper(
             MethodNode method, String helperMethod, String helperDesc) {
         InsnList insns = new InsnList();

tools/java/LandtrainConstraintAuthHelper.java

@@ -7,6 +7,7 @@ import java.util.List;
 import java.util.Set;
 import zombie.characters.IsoGameCharacter;
 import zombie.characters.IsoPlayer;
+import zombie.core.physics.CarController;
 
 /**
  * Resolves the effective driver for constraint auth in chained towing.
@@ -195,4 +196,10 @@ public final class LandtrainConstraintAuthHelper {
             }
         }
     }
+
+    public static void safeParkControllerLandtrain(CarController controller) {
+        if (controller != null) {
+            controller.park();
+        }
+    }
 }