unpack null's correctly

tes3mp-plugin/src/plugin/mod.rs

@@ -76,6 +76,20 @@ macro_rules! call_instance {
     };
 }
 
+/// Returns Some(string) if $argument is not null else returns None
+#[macro_export]
+macro_rules! maybe_string {
+    ($argument:tt) => {
+        unsafe {
+            if $argument.is_null() {
+                None
+            } else {
+                Some(CStr::from_ptr($argument).to_str().unwrap_or_default())
+            }
+        }
+    };
+}
+
 ///
 /// create and bind C symbols to given struct, should implement Events
 ///
@@ -114,97 +128,78 @@ macro_rules! use_events {
         #[no_mangle]
         #[allow(non_snake_case)]
         pub fn OnActorAI(player_id: c_ushort, description: *const i8) {
-            call_instance!(on_actor_ai, player_id, unsafe {
-                CStr::from_ptr(description).to_str().unwrap_or_default()
-            });
+            call_instance!(on_actor_ai, player_id, maybe_string!(description));
         }
 
         #[no_mangle]
         #[allow(non_snake_case)]
         pub fn OnActorCellChange(player_id: c_ushort, description: *const i8) {
-            call_instance!(on_actor_cell_change, player_id, unsafe {
-                CStr::from_ptr(description).to_str().unwrap_or_default()
-            });
+            call_instance!(on_actor_cell_change, player_id, maybe_string!(description));
         }
 
         #[no_mangle]
         #[allow(non_snake_case)]
         pub fn OnActorDeath(player_id: c_ushort, description: *const i8) {
-            call_instance!(on_actor_death, player_id, unsafe {
-                CStr::from_ptr(description).to_str().unwrap_or_default()
-            });
+            call_instance!(on_actor_death, player_id, maybe_string!(description));
         }
 
         #[no_mangle]
         #[allow(non_snake_case)]
         pub fn OnActorEquipment(player_id: c_ushort, description: *const i8) {
-            call_instance!(on_actor_equipment, player_id, unsafe {
-                CStr::from_ptr(description).to_str().unwrap_or_default()
-            });
+            call_instance!(on_actor_equipment, player_id, maybe_string!(description));
         }
 
         #[no_mangle]
         #[allow(non_snake_case)]
         pub fn OnActorList(player_id: c_ushort, description: *const i8) {
-            call_instance!(on_actor_list, player_id, unsafe {
-                CStr::from_ptr(description).to_str().unwrap_or_default()
-            });
+            call_instance!(on_actor_list, player_id, maybe_string!(description));
         }
 
         #[no_mangle]
         #[allow(non_snake_case)]
         pub fn OnActorTest(player_id: c_ushort, description: *const i8) {
-            call_instance!(on_actor_test, player_id, unsafe {
-                CStr::from_ptr(description).to_str().unwrap_or_default()
-            });
+            call_instance!(on_actor_test, player_id, maybe_string!(description));
         }
 
         #[no_mangle]
         #[allow(non_snake_case)]
         pub fn OnCellDeletion(description: *const i8) {
-            call_instance!(on_cell_deletion, unsafe {
-                CStr::from_ptr(description).to_str().unwrap_or_default()
-            });
+            call_instance!(on_cell_deletion, maybe_string!(description));
         }
 
         #[no_mangle]
         #[allow(non_snake_case)]
         pub fn OnCellLoad(description: *const i8) {
-            call_instance!(on_cell_load, unsafe {
-                CStr::from_ptr(description).to_str().unwrap_or_default()
-            });
+            call_instance!(on_cell_load, maybe_string!(description));
         }
 
         #[no_mangle]
         #[allow(non_snake_case)]
         pub fn OnCellUnload(description: *const i8) {
-            call_instance!(on_cell_unload, unsafe {
-                CStr::from_ptr(description).to_str().unwrap_or_default()
-            });
+            call_instance!(on_cell_unload, maybe_string!(description));
         }
 
         #[no_mangle]
         #[allow(non_snake_case)]
         pub fn OnContainer(player_id: c_ushort, description: *const i8) {
-            call_instance!(on_container, player_id, unsafe {
-                CStr::from_ptr(description).to_str().unwrap_or_default()
-            });
+            call_instance!(on_container, player_id, maybe_string!(description));
         }
 
         #[no_mangle]
         #[allow(non_snake_case)]
         pub fn OnDoorState(player_id: c_ushort, description: *const i8) {
-            call_instance!(on_door_state, player_id, unsafe {
-                CStr::from_ptr(description).to_str().unwrap_or_default()
-            });
+            call_instance!(on_door_state, player_id, maybe_string!(description));
         }
 
         #[no_mangle]
         #[allow(non_snake_case)]
         pub fn OnGUIAction(player_id: c_ushort, message_box_id: c_int, data: *const i8) {
-            call_instance!(on_gui_action, player_id, message_box_id, unsafe {
-                CStr::from_ptr(data).to_str().unwrap_or_default()
-            });
+            call_instance!(
+                on_gui_action,
+                player_id,
+                message_box_id,
+                maybe_string!(data)
+            );
         }
 
         #[no_mangle]
@@ -216,65 +211,49 @@ macro_rules! use_events {
         #[no_mangle]
         #[allow(non_snake_case)]
         pub fn OnObjectActivate(player_id: c_ushort, description: *const i8) {
-            call_instance!(on_object_activate, player_id, unsafe {
-                CStr::from_ptr(description).to_str().unwrap_or_default()
-            });
+            call_instance!(on_object_activate, player_id, maybe_string!(description));
         }
 
         #[no_mangle]
         #[allow(non_snake_case)]
         pub fn OnObjectDelete(player_id: c_ushort, description: *const i8) {
-            call_instance!(on_object_delete, player_id, unsafe {
-                CStr::from_ptr(description).to_str().unwrap_or_default()
-            });
+            call_instance!(on_object_delete, player_id, maybe_string!(description));
         }
 
         #[no_mangle]
         #[allow(non_snake_case)]
         pub fn OnObjectLock(player_id: c_ushort, description: *const i8) {
-            call_instance!(on_object_lock, player_id, unsafe {
-                CStr::from_ptr(description).to_str().unwrap_or_default()
-            });
+            call_instance!(on_object_lock, player_id, maybe_string!(description));
         }
 
         #[no_mangle]
         #[allow(non_snake_case)]
         pub fn OnObjectPlace(player_id: c_ushort, description: *const i8) {
-            call_instance!(on_object_place, player_id, unsafe {
-                CStr::from_ptr(description).to_str().unwrap_or_default()
-            });
+            call_instance!(on_object_place, player_id, maybe_string!(description));
         }
 
         #[no_mangle]
         #[allow(non_snake_case)]
         pub fn OnObjectScale(player_id: c_ushort, description: *const i8) {
-            call_instance!(on_object_scale, player_id, unsafe {
-                CStr::from_ptr(description).to_str().unwrap_or_default()
-            });
+            call_instance!(on_object_scale, player_id, maybe_string!(description));
         }
 
         #[no_mangle]
         #[allow(non_snake_case)]
         pub fn OnObjectSpawn(player_id: c_ushort, description: *const i8) {
-            call_instance!(on_object_spawn, player_id, unsafe {
-                CStr::from_ptr(description).to_str().unwrap_or_default()
-            });
+            call_instance!(on_object_spawn, player_id, maybe_string!(description));
         }
 
         #[no_mangle]
         #[allow(non_snake_case)]
         pub fn OnObjectState(player_id: c_ushort, description: *const i8) {
-            call_instance!(on_object_state, player_id, unsafe {
-                CStr::from_ptr(description).to_str().unwrap_or_default()
-            });
+            call_instance!(on_object_state, player_id, maybe_string!(description));
         }
 
         #[no_mangle]
         #[allow(non_snake_case)]
         pub fn OnObjectTrap(player_id: c_ushort, description: *const i8) {
-            call_instance!(on_object_trap, player_id, unsafe {
-                CStr::from_ptr(description).to_str().unwrap_or_default()
-            });
+            call_instance!(on_object_trap, player_id, maybe_string!(description));
         }
 
         #[no_mangle]
@@ -406,9 +385,7 @@ macro_rules! use_events {
         #[no_mangle]
         #[allow(non_snake_case)]
         pub fn OnPlayerSendMessage(player_id: c_ushort, message: *const i8) {
-            call_instance!(on_player_send_message, player_id, unsafe {
-                CStr::from_ptr(message).to_str().unwrap_or_default()
-            });
+            call_instance!(on_player_send_message, player_id, maybe_string!(message));
         }
 
         #[no_mangle]
@@ -450,17 +427,13 @@ macro_rules! use_events {
         #[no_mangle]
         #[allow(non_snake_case)]
         pub fn OnServerScriptCrash(error: *const i8) {
-            call_instance!(on_server_script_crash, unsafe {
-                CStr::from_ptr(error).to_str().unwrap_or_default()
-            });
+            call_instance!(on_server_script_crash, maybe_string!(error));
         }
 
         #[no_mangle]
         #[allow(non_snake_case)]
         pub fn OnVideoPlay(player_id: c_ushort, description: *const i8) {
-            call_instance!(on_video_play, player_id, unsafe {
-                CStr::from_ptr(description).to_str().unwrap_or_default()
-            });
+            call_instance!(on_video_play, player_id, maybe_string!(description));
         }
 
         #[no_mangle]
@@ -488,32 +461,32 @@ pub trait Events: Sized {
     fn new() -> Self;
     fn on_any(&mut self, event_name: &str) {}
 
-    fn on_actor_ai(&mut self, player_id: c_ushort, description: &str) {}
-    fn on_actor_cell_change(&mut self, player_id: c_ushort, description: &str) {}
-    fn on_actor_death(&mut self, player_id: c_ushort, description: &str) {}
-    fn on_actor_equipment(&mut self, player_id: c_ushort, description: &str) {}
-    fn on_actor_list(&mut self, player_id: c_ushort, description: &str) {}
-    fn on_actor_test(&mut self, player_id: c_ushort, description: &str) {}
+    fn on_actor_ai(&mut self, player_id: c_ushort, description: Option<&str>) {}
+    fn on_actor_cell_change(&mut self, player_id: c_ushort, description: Option<&str>) {}
+    fn on_actor_death(&mut self, player_id: c_ushort, description: Option<&str>) {}
+    fn on_actor_equipment(&mut self, player_id: c_ushort, description: Option<&str>) {}
+    fn on_actor_list(&mut self, player_id: c_ushort, description: Option<&str>) {}
+    fn on_actor_test(&mut self, player_id: c_ushort, description: Option<&str>) {}
 
-    fn on_cell_deletion(&mut self, description: &str) {}
-    fn on_cell_load(&mut self, description: &str) {}
-    fn on_cell_unload(&mut self, description: &str) {}
+    fn on_cell_deletion(&mut self, description: Option<&str>) {}
+    fn on_cell_load(&mut self, description: Option<&str>) {}
+    fn on_cell_unload(&mut self, description: Option<&str>) {}
 
-    fn on_container(&mut self, player_id: c_ushort, description: &str) {}
-    fn on_door_state(&mut self, player_id: c_ushort, description: &str) {}
+    fn on_container(&mut self, player_id: c_ushort, description: Option<&str>) {}
+    fn on_door_state(&mut self, player_id: c_ushort, description: Option<&str>) {}
 
-    fn on_gui_action(&mut self, player_id: c_ushort, message_box_id: c_int, data: &str) {}
+    fn on_gui_action(&mut self, player_id: c_ushort, message_box_id: c_int, data: Option<&str>) {}
 
     fn on_mp_num_increment(&mut self, current_mp_num: c_int) {}
 
-    fn on_object_activate(&mut self, player_id: c_ushort, description: &str) {}
-    fn on_object_delete(&mut self, player_id: c_ushort, description: &str) {}
-    fn on_object_lock(&mut self, player_id: c_ushort, description: &str) {}
-    fn on_object_place(&mut self, player_id: c_ushort, description: &str) {}
-    fn on_object_scale(&mut self, player_id: c_ushort, description: &str) {}
-    fn on_object_spawn(&mut self, player_id: c_ushort, description: &str) {}
-    fn on_object_state(&mut self, player_id: c_ushort, description: &str) {}
-    fn on_object_trap(&mut self, player_id: c_ushort, description: &str) {}
+    fn on_object_activate(&mut self, player_id: c_ushort, description: Option<&str>) {}
+    fn on_object_delete(&mut self, player_id: c_ushort, description: Option<&str>) {}
+    fn on_object_lock(&mut self, player_id: c_ushort, description: Option<&str>) {}
+    fn on_object_place(&mut self, player_id: c_ushort, description: Option<&str>) {}
+    fn on_object_scale(&mut self, player_id: c_ushort, description: Option<&str>) {}
+    fn on_object_spawn(&mut self, player_id: c_ushort, description: Option<&str>) {}
+    fn on_object_state(&mut self, player_id: c_ushort, description: Option<&str>) {}
+    fn on_object_trap(&mut self, player_id: c_ushort, description: Option<&str>) {}
 
     fn on_player_attribute(&mut self, player_id: c_ushort) {}
     fn on_player_book(&mut self, player_id: c_ushort) {}
@@ -536,7 +509,7 @@ pub trait Events: Sized {
     fn on_player_reputation(&mut self, player_id: c_ushort) {}
     fn on_player_rest(&mut self, player_id: c_ushort) {}
     fn on_player_resurrect(&mut self, player_id: c_ushort) {}
-    fn on_player_send_message(&mut self, player_id: c_ushort, message: &str) {}
+    fn on_player_send_message(&mut self, player_id: c_ushort, message: Option<&str>) {}
     fn on_player_shapeshift(&mut self, player_id: c_ushort) {}
     fn on_player_skill(&mut self, player_id: c_ushort) {}
     fn on_player_spellbook(&mut self, player_id: c_ushort) {}
@@ -549,9 +522,9 @@ pub trait Events: Sized {
     fn on_server_exit(&mut self, is_error: bool) {}
     fn on_server_init(&mut self) {}
     fn on_server_post_init(&mut self) {}
-    fn on_server_script_crash(&mut self, error: &str) {}
+    fn on_server_script_crash(&mut self, error: Option<&str>) {}
 
-    fn on_video_play(&mut self, player_id: c_ushort, description: &str) {}
+    fn on_video_play(&mut self, player_id: c_ushort, description: Option<&str>) {}
 
     fn on_world_kill_count(&mut self, player_id: c_ushort) {}
     fn on_world_map(&mut self, player_id: c_ushort) {}