Matrix: fix crash when a room is being removed in one thread and the room description is set in another, at the same time

3 files changed, 16 insertions, 17 deletions

diff --git a/plugins/Matrix.hpp b/plugins/Matrix.hpp
index be89adb..df8fa43 100644
--- a/plugins/Matrix.hpp
+++ b/plugins/Matrix.hpp
@@ -136,7 +136,7 @@ namespace QuickMedia {
         bool last_message_read = true;
         bool users_fetched = false;
         time_t last_read_message_timestamp = 0;
-        void *userdata = nullptr; // Pointer to BodyItem. Note: this has to be valid as long as the room is valid
+        std::shared_ptr<BodyItem> body_item;
 
         // These are messages fetched with |Matrix::get_message_by_id|. Needed to show replies, when replying to old message not part of /sync.
         // The value is nullptr if the message is fetched and cached but the event if referenced an invalid message.
diff --git a/src/QuickMedia.cpp b/src/QuickMedia.cpp
index 719345d..76bd084 100644
--- a/src/QuickMedia.cpp
+++ b/src/QuickMedia.cpp
@@ -3440,7 +3440,7 @@ namespace QuickMedia {
         process_pinned_events(std::move(pinned_events));
         tabs[PINNED_TAB_INDEX].body->select_last_item();
 
-        room_name_text.setString(static_cast<BodyItem*>(current_room->userdata)->get_title());
+        room_name_text.setString(current_room->body_item->get_title());
         room_avatar_thumbnail_data = std::make_shared<ThumbnailData>();
 
         read_marker_timeout_ms = 0;
@@ -4429,8 +4429,8 @@ namespace QuickMedia {
                 typing_state_queue.push(false);
             }
 
-            if(current_room && current_room->userdata && room_avatar_thumbnail_data->loading_state == LoadingState::NOT_LOADED)
-                AsyncImageLoader::get_instance().load_thumbnail(static_cast<BodyItem*>(current_room->userdata)->thumbnail_url, false, sf::Vector2i(32, 32), use_tor, room_avatar_thumbnail_data);
+            if(current_room && current_room->body_item && room_avatar_thumbnail_data->loading_state == LoadingState::NOT_LOADED)
+                AsyncImageLoader::get_instance().load_thumbnail(current_room->body_item->thumbnail_url, false, sf::Vector2i(32, 32), use_tor, room_avatar_thumbnail_data);
 
             if(room_avatar_thumbnail_data->loading_state == LoadingState::FINISHED_LOADING && room_avatar_thumbnail_data->image->getSize().x > 0 && room_avatar_thumbnail_data->image->getSize().y > 0) {
                 if(!room_avatar_thumbnail_data->texture.loadFromImage(*room_avatar_thumbnail_data->image))
@@ -4686,10 +4686,9 @@ namespace QuickMedia {
                 tabs[MESSAGES_TAB_INDEX].body->draw_item(window, currently_operating_on_item.get(), body_item_pos, body_item_size);
             }
 
-            if(selected_tab == MESSAGES_TAB_INDEX && current_room && current_room->userdata && !current_room->last_message_read) {
+            if(selected_tab == MESSAGES_TAB_INDEX && current_room && current_room->body_item && !current_room->last_message_read) {
                 if(tabs[selected_tab].body->is_last_item_fully_visible()) {
-                    BodyItem *current_room_body_item = static_cast<BodyItem*>(current_room->userdata);
-                    std::string room_desc = current_room_body_item->get_description();
+                    std::string room_desc = current_room->body_item->get_description();
                     if(strncmp(room_desc.c_str(), "Unread: ", 8) == 0)
                         room_desc = room_desc.substr(8);
                     size_t last_line_start = room_desc.rfind('\n');
@@ -4699,9 +4698,9 @@ namespace QuickMedia {
                         if(last_line_size >= 23 && memcmp(&room_desc[last_line_start], "** ", 3) == 0 && memcmp(&room_desc[room_desc.size() - 20], "unread mention(s) **", 20) == 0)
                             room_desc.erase(room_desc.begin() + last_line_start - 1, room_desc.end());
                     }
-                    current_room_body_item->set_description(std::move(room_desc));
+                    current_room->body_item->set_description(std::move(room_desc));
                     // TODO: Show a line like nheko instead for unread messages, or something else
-                    current_room_body_item->set_title_color(sf::Color::White);
+                    current_room->body_item->set_title_color(sf::Color::White);
                     current_room->last_message_read = true;
                     // TODO: Maybe set this instead when the mention is visible on the screen?
                     current_room->unread_notification_count = 0;
diff --git a/src/plugins/Matrix.cpp b/src/plugins/Matrix.cpp
index ba8533b..3a2c02c 100644
--- a/src/plugins/Matrix.cpp
+++ b/src/plugins/Matrix.cpp
@@ -296,6 +296,8 @@ namespace QuickMedia {
         //message_by_event_id.clear();
         pinned_events.clear();
         tags.clear();
+        // TODO: Do this? what if its being used in another thread?
+        //body_item.reset();
     }
 
     MatrixQuickMedia::MatrixQuickMedia(Program *program, Matrix *matrix, MatrixRoomsPage *rooms_page, MatrixRoomTagsPage *room_tags_page, MatrixInvitesPage *invites_page) :
@@ -317,7 +319,7 @@ namespace QuickMedia {
         body_item->userdata = room; // Note: this has to be valid as long as the room list is valid!
         body_item->thumbnail_mask_type = ThumbnailMaskType::CIRCLE;
         body_item->thumbnail_size = sf::Vector2i(32, 32);
-        room->userdata = body_item.get();
+        room->body_item = body_item;
         rooms_page->add_body_item(body_item);
         room_body_item_by_room[room] = body_item;
     }
@@ -484,9 +486,8 @@ namespace QuickMedia {
         if(last_new_message->timestamp > read_marker_message_timestamp)
             last_unread_message = last_new_message.get();
 
-        BodyItem *room_body_item = static_cast<BodyItem*>(room->userdata);
         //assert(room_body_item);
-        if(!room_body_item)
+        if(!room->body_item)
             return;
 
         if(last_unread_message && !sync_is_cache) {
@@ -494,14 +495,14 @@ namespace QuickMedia {
             int unread_notification_count = room->unread_notification_count;
             if(unread_notification_count > 0)
                 room_desc += "\n** " + std::to_string(unread_notification_count) + " unread mention(s) **"; // TODO: Better notification?
-            room_body_item->set_description(std::move(room_desc));
-            room_body_item->set_title_color(sf::Color(255, 100, 100));
+            room->body_item->set_description(std::move(room_desc));
+            room->body_item->set_title_color(sf::Color(255, 100, 100));
             room->last_message_read = false;
 
             rooms_page->move_room_to_top(room);
             room_tags_page->move_room_to_top(room);
         } else if(is_initial_sync) {
-            room_body_item->set_description(matrix->message_get_author_displayname(last_new_message.get()) + ": " + message_to_room_description_text(last_new_message.get()));
+            room->body_item->set_description(matrix->message_get_author_displayname(last_new_message.get()) + ": " + message_to_room_description_text(last_new_message.get()));
         }
     }
 
@@ -608,8 +609,7 @@ namespace QuickMedia {
         // TODO: Optimize with hash map instead of linear search? or cache the index
         std::lock_guard<std::mutex> lock(mutex);
 #if 1
-        BodyItem *room_body_item = static_cast<BodyItem*>(room->userdata);
-        int room_body_index = body->get_index_by_body_item(room_body_item);
+        int room_body_index = body->get_index_by_body_item(room->body_item.get());
         if(room_body_index != -1) {
             std::shared_ptr<BodyItem> body_item = body->items[room_body_index];
             int body_swap_index = -1;