Recover MTP/USB after Mac sleep without requiring a reboot.

Tear down stale libusb handles on sleep/wake, skip CloseSession on dead pipes, and aggressively rescan until the Switch reconnects.

src/mtp/MTPSession.cpp

@@ -90,8 +90,11 @@ MTPSession::MTPSession() {
 }
 
 MTPSession::~MTPSession() {
-    if (connected_) disconnect();
-    if (ctx_) libusb_exit(ctx_);
+    try { disconnect(true); } catch (...) {}
+    if (ctx_) {
+        libusb_exit(ctx_);
+        ctx_ = nullptr;
+    }
 }
 
 // ─── Device detection ─────────────────────────────────────────────────────────
@@ -293,20 +296,26 @@ DeviceInfo MTPSession::connect() {
 }
 
 // ─── Disconnect ───────────────────────────────────────────────────────────────
-void MTPSession::disconnect() {
-    if (!connected_.load()) return;
-    connected_.store(false);
+void MTPSession::disconnect(bool force) {
+    const bool was_connected = connected_.exchange(false);
+    if (!was_connected && !handle_) return;
 
-    try {
-        send_command(OpCode::CloseSession);
-        receive_response(); // best-effort; ignore result
-    } catch (...) {}
+    // After host sleep the bulk pipe is often dead — CloseSession would hang
+    // on a 5s timeout and leave Darwin USB in a worse state.
+    if (!force && handle_) {
+        try {
+            send_command(OpCode::CloseSession);
+            receive_response(); // best-effort; ignore result
+        } catch (...) {}
+    }
 
     if (handle_) {
+        // Best-effort; after suspend these calls frequently return errors.
         libusb_release_interface(handle_, ep_.interface_num);
         libusb_close(handle_);
         handle_ = nullptr;
     }
+    transaction_id_ = 0;
 }
 
 // ─── Raw USB I/O ──────────────────────────────────────────────────────────────

src/mtp/MTPSession.hpp

@@ -40,7 +40,8 @@ public:
     DeviceInfo connect();
 
     // Close MTP session and release USB resources.
-    void disconnect();
+    // force=true skips CloseSession (use after sleep/wake when the pipe is dead).
+    void disconnect(bool force = false);
 
     bool is_connected() const { return connected_.load(); }
 

src/ui/App.hpp

@@ -61,6 +61,10 @@ public:
     void do_create_folder(const std::string& name);
     void reconnect();
 
+    // macOS sleep/wake — tear down stale libusb state and reconnect.
+    void notify_system_sleep();
+    void notify_system_wake();
+
     bool connected() const { return connected_.load(); }
 
     // Drop-zone rect (CSS pixels, origin top-left) updated by the web UI.
@@ -86,6 +90,8 @@ private:
     void device_monitor_loop(std::stop_token st);
     void on_device_connected(mtp::DeviceInfo di);
     void on_device_disconnected();
+    // Drop session + libusb context without MTP CloseSession (post-sleep recovery).
+    void force_usb_teardown(const std::string& status_key);
 
     // ── Status bar ────────────────────────────────────────────────────────────
     // key is an i18n id (e.g. "status.connected"); args fill {name}/{error}/… placeholders.
@@ -101,7 +107,11 @@ private:
     std::unique_ptr<transfer::TransferEngine> engine_;
 
     std::atomic<bool>   connected_{false};
+    std::atomic<bool>   usb_recovery_pending_{false};
+    // After wake/sleep, poll USB more often for a while (monitor iterations).
+    std::atomic<int>    fast_reconnect_remaining_{0};
     std::jthread        monitor_thread_;
+    void*               wake_observer_ = nullptr; // OmniMTPWakeObserver*
     mutable std::mutex  device_mtx_;
     mtp::DeviceInfo     device_info_;
 

src/ui/App.mm

@@ -1,5 +1,6 @@
 #include "App.hpp"
 #import <Foundation/Foundation.h>
+#import <AppKit/AppKit.h>
 #include <stdexcept>
 #include <cstdio>
 #include <filesystem>
@@ -51,25 +52,82 @@ static std::string fmt_eta(double s) {
     char b[16]; snprintf(b,sizeof(b),"%dh%02dm",si/3600,(si%3600)/60); return b;
 }
 
+} // namespace omniMTP
+
+// ─── Sleep/wake observer (must live outside the C++ namespace for ObjC) ────────
+@interface OmniMTPWakeObserver : NSObject
+@property (nonatomic, assign) omniMTP::App* app;
+@end
+
+@implementation OmniMTPWakeObserver
+- (void)onWillSleep:(NSNotification*)notification {
+    (void)notification;
+    if (self.app) self.app->notify_system_sleep();
+}
+- (void)onDidWake:(NSNotification*)notification {
+    (void)notification;
+    if (self.app) self.app->notify_system_wake();
+}
+@end
+
+namespace omniMTP {
+
 // ─── App lifecycle ────────────────────────────────────────────────────────────
 App::App() : download_path_(fs::path(std::getenv("HOME") ? std::getenv("HOME") : "/")) {}
 App::~App() { shutdown(); }
 
 void App::init() {
     download_path_ = fs::path(std::getenv("HOME") ? std::getenv("HOME") : "/");
+
+    OmniMTPWakeObserver* observer = [OmniMTPWakeObserver new];
+    observer.app = this;
+    wake_observer_ = (__bridge_retained void*)observer;
+    NSNotificationCenter* nc = [[NSWorkspace sharedWorkspace] notificationCenter];
+    [nc addObserver:observer selector:@selector(onWillSleep:)
+               name:NSWorkspaceWillSleepNotification object:nil];
+    [nc addObserver:observer selector:@selector(onDidWake:)
+               name:NSWorkspaceDidWakeNotification object:nil];
+
     monitor_thread_ = std::jthread([this](std::stop_token st) { device_monitor_loop(st); });
 }
 
 void App::shutdown() {
+    if (wake_observer_) {
+        OmniMTPWakeObserver* observer = (__bridge_transfer OmniMTPWakeObserver*)wake_observer_;
+        wake_observer_ = nullptr;
+        observer.app = nullptr;
+        [[[NSWorkspace sharedWorkspace] notificationCenter] removeObserver:observer];
+    }
     monitor_thread_.request_stop();
     engine_.reset();
-    if (connected_.load())
-        try { if (session_) session_->disconnect(); } catch (...) {}
+    if (session_)
+        try { session_->disconnect(true); } catch (...) {}
+}
+
+void App::notify_system_sleep() {
+    // Drop the session before USB powers down so we don't keep a zombie handle.
+    usb_recovery_pending_.store(true);
+    fast_reconnect_remaining_.store(0);
+}
+
+void App::notify_system_wake() {
+    // Fresh libusb context + aggressive rescan until the Switch reappears.
+    usb_recovery_pending_.store(true);
+    fast_reconnect_remaining_.store(120); // ~30–60s of faster retries
+    set_status("status.usb_recovering", {}, 8.f);
 }
 
 // ─── Device monitor ───────────────────────────────────────────────────────────
 void App::device_monitor_loop(std::stop_token st) {
     while (!st.stop_requested()) {
+        if (usb_recovery_pending_.exchange(false)) {
+            force_usb_teardown("status.usb_recovering");
+            // Let Darwin finish re-enumerating USB after wake.
+            for (int i = 0; i < 6 && !st.stop_requested(); ++i)
+                std::this_thread::sleep_for(std::chrono::milliseconds(250));
+            continue;
+        }
+
         if (!connected_.load()) {
             try {
                 auto sess = std::make_unique<mtp::MTPSession>();
@@ -86,6 +144,7 @@ void App::device_monitor_loop(std::stop_token st) {
                     });
                 }
                 on_device_connected(std::move(di));
+                fast_reconnect_remaining_.store(0);
             } catch (...) {}
         } else {
             bool transfer_active = false;
@@ -105,11 +164,36 @@ void App::device_monitor_loop(std::stop_token st) {
                 }
             }
         }
-        for (int i = 0; i < 8 && !st.stop_requested(); ++i)
+
+        int fast = fast_reconnect_remaining_.load();
+        int slices = (fast > 0) ? 2 : 8; // 500ms vs 2s
+        if (fast > 0)
+            fast_reconnect_remaining_.fetch_sub(1);
+        for (int i = 0; i < slices && !st.stop_requested(); ++i)
             std::this_thread::sleep_for(std::chrono::milliseconds(250));
     }
 }
 
+void App::force_usb_teardown(const std::string& status_key) {
+    {
+        std::lock_guard lock(device_mtx_);
+        if (engine_) { engine_->cancel_all(); engine_.reset(); }
+        ops_.reset();
+        if (session_) {
+            // force=true: skip MTP CloseSession; destroy libusb context entirely.
+            try { session_->disconnect(true); } catch (...) {}
+            session_.reset();
+        }
+        storages_.clear();
+        remote_entries_.clear();
+        remote_nav_stack_.clear();
+    }
+    connected_.store(false);
+    remote_needs_refresh_ = false;
+    if (!status_key.empty())
+        set_status(status_key, {}, 8.f);
+}
+
 void App::on_device_connected(mtp::DeviceInfo di) {
     {
         std::lock_guard lock(device_mtx_);
@@ -140,18 +224,7 @@ void App::on_device_connected(mtp::DeviceInfo di) {
 }
 
 void App::on_device_disconnected() {
-    {
-        std::lock_guard lock(device_mtx_);
-        if (engine_) { engine_->cancel_all(); engine_.reset(); }
-        ops_.reset();
-        if (session_) { try { session_->disconnect(); } catch (...) {} session_.reset(); }
-        storages_.clear();
-        remote_entries_.clear();
-        remote_nav_stack_.clear();
-    }
-    connected_.store(false);
-    remote_needs_refresh_ = false;
-    set_status("status.disconnected");
+    force_usb_teardown("status.disconnected");
 }
 
 // ─── Remote filesystem ────────────────────────────────────────────────────────
@@ -402,6 +475,10 @@ void App::do_create_folder(const std::string& name) {
     catch (...) {}
     refresh_remote();
 }
-void App::reconnect() { on_device_disconnected(); }
+void App::reconnect() {
+    usb_recovery_pending_.store(true);
+    fast_reconnect_remaining_.store(60);
+    set_status("status.usb_recovering", {}, 8.f);
+}
 
 } // namespace omniMTP

src/ui/webroot/lang/de.json

@@ -46,5 +46,6 @@
   "menu.about": "Über OmniMTP",
   "about.tagline": "Nintendo Switch MTP-Client für macOS",
   "about.version": "Version {version}",
-  "about.copyright": "Copyright © 2026 NiklasCFW"
+  "about.copyright": "Copyright © 2026 NiklasCFW",
+  "status.usb_recovering": "USB wird nach dem Ruhezustand neu verbunden…"
 }

src/ui/webroot/lang/en.json

@@ -46,5 +46,6 @@
   "menu.about": "About OmniMTP",
   "about.tagline": "Nintendo Switch MTP Client for macOS",
   "about.version": "Version {version}",
-  "about.copyright": "Copyright © 2026 NiklasCFW"
+  "about.copyright": "Copyright © 2026 NiklasCFW",
+  "status.usb_recovering": "Reconnecting USB after sleep…"
 }

src/ui/webroot/lang/es.json

@@ -46,5 +46,6 @@
   "menu.about": "Acerca de OmniMTP",
   "about.tagline": "Cliente MTP de Nintendo Switch para macOS",
   "about.version": "Versión {version}",
-  "about.copyright": "Copyright © 2026 NiklasCFW"
+  "about.copyright": "Copyright © 2026 NiklasCFW",
+  "status.usb_recovering": "Reconectando USB tras la suspensión…"
 }

src/ui/webroot/lang/fr.json

@@ -46,5 +46,6 @@
   "menu.about": "À propos d’OmniMTP",
   "about.tagline": "Client MTP Nintendo Switch pour macOS",
   "about.version": "Version {version}",
-  "about.copyright": "Copyright © 2026 NiklasCFW"
+  "about.copyright": "Copyright © 2026 NiklasCFW",
+  "status.usb_recovering": "Reconnexion USB après veille…"
 }

src/ui/webroot/lang/it.json

@@ -46,5 +46,6 @@
   "menu.about": "Informazioni su OmniMTP",
   "about.tagline": "Client MTP Nintendo Switch per macOS",
   "about.version": "Versione {version}",
-  "about.copyright": "Copyright © 2026 NiklasCFW"
+  "about.copyright": "Copyright © 2026 NiklasCFW",
+  "status.usb_recovering": "Riconnessione USB dopo lo standby…"
 }

src/ui/webroot/lang/ja.json

@@ -46,5 +46,6 @@
   "menu.about": "OmniMTPについて",
   "about.tagline": "macOS向け Nintendo Switch MTPクライアント",
   "about.version": "バージョン {version}",
-  "about.copyright": "Copyright © 2026 NiklasCFW"
+  "about.copyright": "Copyright © 2026 NiklasCFW",
+  "status.usb_recovering": "スリープ後、USBを再接続しています…"
 }

src/ui/webroot/lang/nl.json

@@ -46,5 +46,6 @@
   "menu.about": "Over OmniMTP",
   "about.tagline": "Nintendo Switch MTP-client voor macOS",
   "about.version": "Versie {version}",
-  "about.copyright": "Copyright © 2026 NiklasCFW"
+  "about.copyright": "Copyright © 2026 NiklasCFW",
+  "status.usb_recovering": "USB opnieuw verbinden na slaapstand…"
 }

src/ui/webroot/lang/pt.json

@@ -46,5 +46,6 @@
   "menu.about": "Sobre o OmniMTP",
   "about.tagline": "Cliente MTP Nintendo Switch para macOS",
   "about.version": "Versão {version}",
-  "about.copyright": "Copyright © 2026 NiklasCFW"
+  "about.copyright": "Copyright © 2026 NiklasCFW",
+  "status.usb_recovering": "Reconectando USB após a suspensão…"
 }

src/ui/webroot/lang/ru.json

@@ -46,5 +46,6 @@
   "menu.about": "О программе OmniMTP",
   "about.tagline": "MTP-клиент Nintendo Switch для macOS",
   "about.version": "Версия {version}",
-  "about.copyright": "Copyright © 2026 NiklasCFW"
+  "about.copyright": "Copyright © 2026 NiklasCFW",
+  "status.usb_recovering": "Повторное подключение USB после сна…"
 }

src/ui/webroot/lang/zh-Hans.json

@@ -46,5 +46,6 @@
   "menu.about": "关于 OmniMTP",
   "about.tagline": "适用于 macOS 的 Nintendo Switch MTP 客户端",
   "about.version": "版本 {version}",
-  "about.copyright": "Copyright © 2026 NiklasCFW"
+  "about.copyright": "Copyright © 2026 NiklasCFW",
+  "status.usb_recovering": "休眠后正在重新连接 USB…"
 }