[fs/core] Load external content without NAND install (#2862)

Adds the capability to add DLC and Updates without installing them to NAND. This was tested on Windows only and needs Android integration.

Co-authored-by: crueter <crueter@eden-emu.dev>
Co-authored-by: wildcard <wildcard@eden-emu.dev>
Co-authored-by: nekle <nekle@protonmail.com>
Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/2862
Reviewed-by: DraVee <dravee@eden-emu.dev>
Reviewed-by: crueter <crueter@eden-emu.dev>
Co-authored-by: Maufeat <sahyno1996@gmail.com>
Co-committed-by: Maufeat <sahyno1996@gmail.com>

src/yuzu/configuration/configure_dialog.cpp

@@ -1,4 +1,4 @@
-// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
 // SPDX-License-Identifier: GPL-3.0-or-later
 
 // SPDX-FileCopyrightText: 2016 Citra Emulator Project
@@ -99,6 +99,8 @@ ConfigureDialog::ConfigureDialog(QWidget* parent, HotkeyRegistry& registry_,
         }
     });
     connect(ui_tab.get(), &ConfigureUi::LanguageChanged, this, &ConfigureDialog::OnLanguageChanged);
+    connect(general_tab.get(), &ConfigureGeneral::ExternalContentDirsChanged, this,
+            &ConfigureDialog::ExternalContentDirsChanged);
     connect(ui->selectorList, &QListWidget::itemSelectionChanged, this,
             &ConfigureDialog::UpdateVisibleTabs);
 

src/yuzu/configuration/configure_dialog.h

@@ -1,4 +1,4 @@
-// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
 // SPDX-License-Identifier: GPL-3.0-or-later
 
 // SPDX-FileCopyrightText: 2016 Citra Emulator Project
@@ -62,6 +62,7 @@ private slots:
 
 signals:
     void LanguageChanged(const QString& locale);
+    void ExternalContentDirsChanged();
 
 private:
     void changeEvent(QEvent* event) override;

src/yuzu/configuration/configure_filesystem.cpp

@@ -1,4 +1,4 @@
-// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
 // SPDX-License-Identifier: GPL-3.0-or-later
 
 // SPDX-FileCopyrightText: Copyright 2019 yuzu Emulator Project
@@ -38,9 +38,9 @@ ConfigureFilesystem::ConfigureFilesystem(QWidget* parent)
     connect(ui->reset_game_list_cache, &QPushButton::pressed, this,
             &ConfigureFilesystem::ResetMetadata);
 
-    connect(ui->gamecard_inserted, &QCheckBox::STATE_CHANGED, this,
+    connect(ui->gamecard_inserted, &QCheckBox::stateChanged, this,
             &ConfigureFilesystem::UpdateEnabledControls);
-    connect(ui->gamecard_current_game, &QCheckBox::STATE_CHANGED, this,
+    connect(ui->gamecard_current_game, &QCheckBox::stateChanged, this,
             &ConfigureFilesystem::UpdateEnabledControls);
 }
 
@@ -278,6 +278,7 @@ void ConfigureFilesystem::UpdateEnabledControls() {
                                          !ui->gamecard_current_game->isChecked());
 }
 
+
 void ConfigureFilesystem::RetranslateUI() {
     ui->retranslateUi(this);
 }

src/yuzu/configuration/configure_filesystem.h

@@ -1,4 +1,4 @@
-// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
 // SPDX-License-Identifier: GPL-3.0-or-later
 
 // SPDX-FileCopyrightText: Copyright 2019 yuzu Emulator Project

src/yuzu/configuration/configure_general.cpp

@@ -1,4 +1,4 @@
-// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
 // SPDX-License-Identifier: GPL-3.0-or-later
 
 // SPDX-FileCopyrightText: 2016 Citra Emulator Project
@@ -7,6 +7,9 @@
 #include <functional>
 #include <utility>
 #include <vector>
+#include <QDir>
+#include <QFileDialog>
+#include <QListWidget>
 #include <QMessageBox>
 #include "common/settings.h"
 #include "core/core.h"
@@ -29,6 +32,15 @@ ConfigureGeneral::ConfigureGeneral(const Core::System& system_,
     connect(ui->button_reset_defaults, &QPushButton::clicked, this,
             &ConfigureGeneral::ResetDefaults);
 
+    connect(ui->add_external_dir_button, &QPushButton::pressed, this,
+            &ConfigureGeneral::AddExternalContentDirectory);
+    connect(ui->remove_external_dir_button, &QPushButton::pressed, this,
+            &ConfigureGeneral::RemoveSelectedExternalContentDirectory);
+    connect(ui->external_content_list, &QListWidget::itemSelectionChanged, this, [this] {
+        ui->remove_external_dir_button->setEnabled(
+            !ui->external_content_list->selectedItems().isEmpty());
+    });
+
     if (!Settings::IsConfiguringGlobal()) {
         ui->button_reset_defaults->setVisible(false);
     }
@@ -36,7 +48,9 @@ ConfigureGeneral::ConfigureGeneral(const Core::System& system_,
 
 ConfigureGeneral::~ConfigureGeneral() = default;
 
-void ConfigureGeneral::SetConfiguration() {}
+void ConfigureGeneral::SetConfiguration() {
+    UpdateExternalContentList();
+}
 
 void ConfigureGeneral::Setup(const ConfigurationShared::Builder& builder) {
     QLayout& general_layout = *ui->general_widget->layout();
@@ -101,6 +115,55 @@ void ConfigureGeneral::ApplyConfiguration() {
     for (const auto& func : apply_funcs) {
         func(powered_on);
     }
+
+    std::vector<std::string> new_dirs;
+    new_dirs.reserve(ui->external_content_list->count());
+    for (int i = 0; i < ui->external_content_list->count(); ++i) {
+        new_dirs.push_back(ui->external_content_list->item(i)->text().toStdString());
+    }
+
+    if (new_dirs != Settings::values.external_content_dirs) {
+        Settings::values.external_content_dirs = std::move(new_dirs);
+        emit ExternalContentDirsChanged();
+    }
+}
+
+void ConfigureGeneral::UpdateExternalContentList() {
+    ui->external_content_list->clear();
+    for (const auto& dir : Settings::values.external_content_dirs) {
+        ui->external_content_list->addItem(QString::fromStdString(dir));
+    }
+}
+
+void ConfigureGeneral::AddExternalContentDirectory() {
+    const QString dir_path = QFileDialog::getExistingDirectory(
+        this, tr("Select External Content Directory..."), QString());
+
+    if (dir_path.isEmpty()) {
+        return;
+    }
+
+    QString normalized_path = QDir::toNativeSeparators(dir_path);
+    if (normalized_path.back() != QDir::separator()) {
+        normalized_path.append(QDir::separator());
+    }
+
+    for (int i = 0; i < ui->external_content_list->count(); ++i) {
+        if (ui->external_content_list->item(i)->text() == normalized_path) {
+            QMessageBox::information(this, tr("Directory Already Added"),
+                                     tr("This directory is already in the list."));
+            return;
+        }
+    }
+
+    ui->external_content_list->addItem(normalized_path);
+}
+
+void ConfigureGeneral::RemoveSelectedExternalContentDirectory() {
+    auto selected = ui->external_content_list->selectedItems();
+    if (!selected.isEmpty()) {
+        qDeleteAll(ui->external_content_list->selectedItems());
+    }
 }
 
 void ConfigureGeneral::changeEvent(QEvent* event) {

src/yuzu/configuration/configure_general.h

@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
 // SPDX-FileCopyrightText: 2016 Citra Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
@@ -39,12 +42,19 @@ public:
     void ApplyConfiguration() override;
     void SetConfiguration() override;
 
+signals:
+    void ExternalContentDirsChanged();
+
 private:
     void Setup(const ConfigurationShared::Builder& builder);
 
     void changeEvent(QEvent* event) override;
     void RetranslateUI();
 
+    void UpdateExternalContentList();
+    void AddExternalContentDirectory();
+    void RemoveSelectedExternalContentDirectory();
+
     std::function<void()> reset_callback;
 
     std::unique_ptr<Ui::ConfigureGeneral> ui;

src/yuzu/configuration/configure_general.ui

@@ -46,6 +46,66 @@
        </layout>
       </widget>
      </item>
+     <item>
+      <widget class="QGroupBox" name="groupBox_external">
+       <property name="title">
+        <string>External Content</string>
+       </property>
+       <layout class="QVBoxLayout" name="verticalLayout_external">
+        <item>
+         <widget class="QLabel" name="label_external_desc">
+          <property name="text">
+           <string>Add directories to scan for DLCs and Updates without installing to NAND</string>
+          </property>
+          <property name="wordWrap">
+           <bool>true</bool>
+          </property>
+         </widget>
+        </item>
+        <item>
+         <widget class="QListWidget" name="external_content_list">
+          <property name="selectionMode">
+           <enum>QAbstractItemView::SingleSelection</enum>
+          </property>
+         </widget>
+        </item>
+        <item>
+         <layout class="QHBoxLayout" name="horizontalLayout_external_buttons">
+          <item>
+           <widget class="QPushButton" name="add_external_dir_button">
+            <property name="text">
+             <string>Add Directory</string>
+            </property>
+           </widget>
+          </item>
+          <item>
+           <widget class="QPushButton" name="remove_external_dir_button">
+            <property name="text">
+             <string>Remove Selected</string>
+            </property>
+            <property name="enabled">
+             <bool>false</bool>
+            </property>
+           </widget>
+          </item>
+          <item>
+           <spacer name="horizontalSpacer_external">
+            <property name="orientation">
+             <enum>Qt::Horizontal</enum>
+            </property>
+            <property name="sizeHint" stdset="0">
+             <size>
+              <width>40</width>
+              <height>20</height>
+             </size>
+            </property>
+           </spacer>
+          </item>
+         </layout>
+        </item>
+       </layout>
+      </widget>
+     </item>
      <item>
       <spacer name="verticalSpacer">
        <property name="orientation">

src/yuzu/configuration/configure_per_game_addons.cpp

@@ -8,6 +8,8 @@
 #include <memory>
 #include <utility>
 
+#include <fmt/format.h>
+
 #include <QHeaderView>
 #include <QMenu>
 #include <QStandardItemModel>
@@ -16,6 +18,7 @@
 #include <QTreeView>
 #include <qstandardpaths.h>
 
+#include "common/common_types.h"
 #include "common/fs/fs.h"
 #include "common/fs/path_util.h"
 #include "configuration/addon/mod_select_dialog.h"
@@ -68,6 +71,8 @@ ConfigurePerGameAddons::ConfigurePerGameAddons(Core::System& system_, QWidget* p
 
     ui->scrollArea->setEnabled(!system.IsPoweredOn());
 
+    connect(item_model, &QStandardItemModel::itemChanged, this,
+            &ConfigurePerGameAddons::OnItemChanged);
     connect(item_model, &QStandardItemModel::itemChanged,
             [] { UISettings::values.is_game_list_reload_pending.exchange(true); });
 
@@ -77,13 +82,37 @@ ConfigurePerGameAddons::ConfigurePerGameAddons(Core::System& system_, QWidget* p
 
 ConfigurePerGameAddons::~ConfigurePerGameAddons() = default;
 
+void ConfigurePerGameAddons::OnItemChanged(QStandardItem* item) {
+    if (update_items.size() > 1 && item->checkState() == Qt::Checked) {
+        auto it = std::find(update_items.begin(), update_items.end(), item);
+        if (it != update_items.end()) {
+            for (auto* update_item : update_items) {
+                if (update_item != item && update_item->checkState() == Qt::Checked) {
+                    disconnect(item_model, &QStandardItemModel::itemChanged, this,
+                              &ConfigurePerGameAddons::OnItemChanged);
+                    update_item->setCheckState(Qt::Unchecked);
+                    connect(item_model, &QStandardItemModel::itemChanged, this,
+                           &ConfigurePerGameAddons::OnItemChanged);
+                }
+            }
+        }
+    }
+}
+
 void ConfigurePerGameAddons::ApplyConfiguration() {
     std::vector<std::string> disabled_addons;
 
     for (const auto& item : list_items) {
         const auto disabled = item.front()->checkState() == Qt::Unchecked;
-        if (disabled)
-            disabled_addons.push_back(item.front()->text().toStdString());
+        if (disabled) {
+            QVariant userData = item.front()->data(Qt::UserRole);
+            if (userData.isValid() && userData.canConvert<quint32>() && item.front()->text() == QStringLiteral("Update")) {
+                quint32 numeric_version = userData.toUInt();
+                disabled_addons.push_back(fmt::format("Update@{}", numeric_version));
+            } else {
+                disabled_addons.push_back(item.front()->text().toStdString());
+            }
+        }
     }
 
     auto current = Settings::values.disabled_addons[title_id];
@@ -194,17 +223,51 @@ void ConfigurePerGameAddons::LoadConfiguration() {
 
     const auto& disabled = Settings::values.disabled_addons[title_id];
 
-    for (const auto& patch : pm.GetPatches(update_raw)) {
+    update_items.clear();
+    list_items.clear();
+    item_model->removeRows(0, item_model->rowCount());
+
+    std::vector<FileSys::Patch> patches = pm.GetPatches(update_raw);
+
+    bool has_enabled_update = false;
+
+    for (const auto& patch : patches) {
         const auto name = QString::fromStdString(patch.name);
 
         auto* const first_item = new QStandardItem;
         first_item->setText(name);
         first_item->setCheckable(true);
 
-        const auto patch_disabled =
-            std::find(disabled.begin(), disabled.end(), name.toStdString()) != disabled.end();
+        const bool is_external_update = patch.type == FileSys::PatchType::Update &&
+                                        patch.source == FileSys::PatchSource::External &&
+                                        patch.numeric_version != 0;
 
-        first_item->setCheckState(patch_disabled ? Qt::Unchecked : Qt::Checked);
+        if (is_external_update) {
+            first_item->setData(static_cast<quint32>(patch.numeric_version), Qt::UserRole);
+        }
+
+        bool patch_disabled = false;
+        if (is_external_update) {
+            std::string disabled_key = fmt::format("Update@{}", patch.numeric_version);
+            patch_disabled = std::find(disabled.begin(), disabled.end(), disabled_key) != disabled.end();
+        } else {
+            patch_disabled = std::find(disabled.begin(), disabled.end(), name.toStdString()) != disabled.end();
+        }
+
+        bool should_enable = !patch_disabled;
+
+        if (patch.type == FileSys::PatchType::Update) {
+            if (should_enable) {
+                if (has_enabled_update) {
+                    should_enable = false;
+                } else {
+                    has_enabled_update = true;
+                }
+            }
+            update_items.push_back(first_item);
+        }
+
+        first_item->setCheckState(should_enable ? Qt::Checked : Qt::Unchecked);
 
         list_items.push_back(QList<QStandardItem*>{
             first_item, new QStandardItem{QString::fromStdString(patch.version)}});

src/yuzu/configuration/configure_per_game_addons.h

@@ -54,6 +54,7 @@ private:
     void RetranslateUI();
 
     void LoadConfiguration();
+    void OnItemChanged(QStandardItem* item);
 
     std::unique_ptr<Ui::ConfigurePerGameAddons> ui;
     FileSys::VirtualFile file;
@@ -64,6 +65,7 @@ private:
     QStandardItemModel* item_model;
 
     std::vector<QList<QStandardItem*>> list_items;
+    std::vector<QStandardItem*> update_items;
 
     Core::System& system;
 };

src/yuzu/game_list.cpp

@@ -16,11 +16,13 @@
 #include <QToolButton>
 #include <QVariantAnimation>
 #include <fmt/ranges.h>
+#include <qfilesystemwatcher.h>
 #include <qnamespace.h>
 #include <qscroller.h>
 #include <qscrollerproperties.h>
 #include "common/common_types.h"
 #include "common/logging/log.h"
+#include "common/settings.h"
 #include "core/core.h"
 #include "core/file_sys/patch_manager.h"
 #include "core/file_sys/registered_cache.h"
@@ -32,6 +34,7 @@
 #include "yuzu/game_list_worker.h"
 #include "yuzu/main_window.h"
 #include "yuzu/util/controller_navigation.h"
+#include "qt_common/qt_common.h"
 
 GameListSearchField::KeyReleaseEater::KeyReleaseEater(GameList* gamelist_, QObject* parent)
     : QObject(parent), gamelist{gamelist_} {}
@@ -325,6 +328,10 @@ GameList::GameList(FileSys::VirtualFilesystem vfs_, FileSys::ManualContentProvid
     watcher = new QFileSystemWatcher(this);
     connect(watcher, &QFileSystemWatcher::directoryChanged, this, &GameList::RefreshGameDirectory);
 
+    external_watcher = new QFileSystemWatcher(this);
+    ResetExternalWatcher();
+    connect(external_watcher, &QFileSystemWatcher::directoryChanged, this, &GameList::RefreshExternalContent);
+
     this->main_window = parent;
     layout = new QVBoxLayout;
     tree_view = new QTreeView;
@@ -919,12 +926,38 @@ const QStringList GameList::supported_file_extensions = {
 
 void GameList::RefreshGameDirectory()
 {
+    // Reset the externals watcher whenever the game list is reloaded,
+    // primarily ensures that new titles and external dirs are caught.
+    ResetExternalWatcher();
+
     if (!UISettings::values.game_dirs.empty() && current_worker != nullptr) {
         LOG_INFO(Frontend, "Change detected in the games directory. Reloading game list.");
+        QtCommon::system->GetFileSystemController().CreateFactories(*QtCommon::vfs);
         PopulateAsync(UISettings::values.game_dirs);
     }
 }
 
+void GameList::RefreshExternalContent() {
+    // TODO: Explore the possibility of only resetting the metadata cache for that specific game.
+    if (!UISettings::values.game_dirs.empty() && current_worker != nullptr) {
+        LOG_INFO(Frontend, "External content directory changed. Clearing metadata cache.");
+        QtCommon::Game::ResetMetadata(false);
+        QtCommon::system->GetFileSystemController().CreateFactories(*QtCommon::vfs);
+        PopulateAsync(UISettings::values.game_dirs);
+    }
+}
+
+void GameList::ResetExternalWatcher() {
+    auto watch_dirs = external_watcher->directories();
+    if (!watch_dirs.isEmpty()) {
+        external_watcher->removePaths(watch_dirs);
+    }
+
+    for (const std::string &dir : Settings::values.external_content_dirs) {
+        external_watcher->addPath(QString::fromStdString(dir));
+    }
+}
+
 void GameList::ToggleFavorite(u64 program_id) {
     if (!UISettings::values.favorited_ids.contains(program_id)) {
         tree_view->setRowHidden(0, item_model->invisibleRootItem()->index(),

src/yuzu/game_list.h

@@ -94,6 +94,8 @@ public:
 
 public slots:
     void RefreshGameDirectory();
+    void RefreshExternalContent();
+    void ResetExternalWatcher();
 
 signals:
     void BootGame(const QString& game_path, StartGameType type);
@@ -160,6 +162,7 @@ private:
     QStandardItemModel* item_model = nullptr;
     std::unique_ptr<GameListWorker> current_worker;
     QFileSystemWatcher* watcher = nullptr;
+    QFileSystemWatcher* external_watcher = nullptr;
     ControllerNavigation* controller_navigation = nullptr;
     CompatibilityList compatibility_list;
 

src/yuzu/main_window.cpp

@@ -3388,6 +3388,8 @@ void MainWindow::OnConfigure() {
                                      !multiplayer_state->IsHostingPublicRoom());
     connect(&configure_dialog, &ConfigureDialog::LanguageChanged, this,
             &MainWindow::OnLanguageChanged);
+    connect(&configure_dialog, &ConfigureDialog::ExternalContentDirsChanged, this,
+            &MainWindow::OnGameListRefresh);
 
     const auto result = configure_dialog.exec();
     if (result != QDialog::Accepted && !UISettings::values.configuration_applied &&
@@ -3907,8 +3909,7 @@ void MainWindow::OnToggleStatusBar() {
     statusBar()->setVisible(ui->action_Show_Status_Bar->isChecked());
 }
 
-void MainWindow::OnGameListRefresh()
-{
+void MainWindow::OnGameListRefresh() {
     // Resets metadata cache and reloads
     QtCommon::Game::ResetMetadata(false);
     game_list->RefreshGameDirectory();