feat: gao --apply switches a running tray's watchdog back on; --optimize exits 2 when not saved

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

Author: Rovey

README.md

@@ -44,7 +44,7 @@ That builds two programs in `.\build\Release\`: `GpuAutoOptimizer.exe`, the wind
 
 Start `GpuAutoOptimizer.exe`. The window shows the GPU, live telemetry, the saved tune and what is applied right now; pick a preset and press **Optimize** (it offers to restart as administrator first, because tuning writes clocks and power limits). The run screen shows temperature, power and every probe as it happens; **Abort** restores stock. The results screen compares before and after and can turn on **apply at every logon**.
 
-With apply-at-logon on, Windows starts the app in the tray at every logon. It applies the saved tune and then keeps it applied: every 30 seconds it reads back what the driver reports. If the tune was reset (a driver reset or TDR), it applies it again; if that happens four times within an hour it stops and tells you the tune is probably not stable; if another program such as MSI Afterburner changed the settings, it leaves them alone and tells you; after a driver update it does not apply the old tune and tells you to optimize again. While it keeps a tune applied (or a run is in progress), closing the window keeps it in the tray and **Exit** in the tray menu quits; otherwise closing the window quits. **Revert to stock** in the tray menu, or `gao --reset` from a shell, puts the card at stock and the watchdog leaves it there until you apply the tune again from the window or the tray menu (`gao --apply` applies it but does not switch the watchdog back on). Only one optimize runs at a time, from the window or the command line.
+With apply-at-logon on, Windows starts the app in the tray at every logon. It applies the saved tune and then keeps it applied: every 30 seconds it reads back what the driver reports. If the tune was reset (a driver reset or TDR), it applies it again; if that happens four times within an hour it stops and tells you the tune is probably not stable; if another program such as MSI Afterburner changed the settings, it leaves them alone and tells you; after a driver update it does not apply the old tune and tells you to optimize again. While it keeps a tune applied (or a run is in progress), closing the window keeps it in the tray and **Exit** in the tray menu quits; otherwise closing the window quits. **Revert to stock** in the tray menu, or `gao --reset` from a shell, puts the card at stock and the watchdog leaves it there until you apply the tune again (window, tray menu or `gao --apply`). Only one optimize runs at a time, from the window or the command line.
 
 ### The command line
 
@@ -59,7 +59,7 @@ With apply-at-logon on, Windows starts the app in the tray at every logon. It ap
 .\build\Release\gao.exe --status
 ```
 
-`--optimize` runs baseline → power → core → memory → 60 s soak (~10 minutes), leaves the result applied until reboot, and keeps a crash journal so a setting that froze the machine is never tried again. Ctrl+C restores stock. The core and memory edges it finds are each re-checked with a 30 s probe before the safety margin is applied, and the memory search stops at the **bandwidth peak** rather than at the highest offset that does not produce errors: GDDR6X and GDDR6 retry failed transfers, so an excessive memory clock costs speed long before it produces a wrong result. `--bandwidth` prints the current memory bandwidth.
+`--optimize` runs baseline → power → core → memory → 60 s soak (~10 minutes), leaves the result applied until reboot (exit code 0; 2 if it was applied but could not be saved), and keeps a crash journal so a setting that froze the machine is never tried again. Ctrl+C restores stock. The core and memory edges it finds are each re-checked with a 30 s probe before the safety margin is applied, and the memory search stops at the **bandwidth peak** rather than at the highest offset that does not produce errors: GDDR6X and GDDR6 retry failed transfers, so an excessive memory clock costs speed long before it produces a wrong result. `--bandwidth` prints the current memory bandwidth.
 
 All state (`gao.json`, the crash journal, `boot.log`) lives in `%ProgramData%\GpuAutoOptimizer`, which users can read but only administrators can write. `--boot on` copies both executables to `%ProgramFiles%\GpuAutoOptimizer\` and registers a logon task (`\GpuAutoOptimizer\BootApply`) that starts that copy of the app in the tray, which re-applies the saved profile and keeps it applied; `--status` says whether the installed copies match your build; if the machine crashes within 2 minutes of three logons in a row, or the NVIDIA driver version changes, boot-apply stops and `--status` / `boot.log` say why. A profile only applies to the card it was tuned on (NVML UUID).
 

docs/hardware-checks.md

@@ -59,7 +59,7 @@ root; adjust the path for a Debug build.
 | 33 | Watchdog re-applies after a TDR | tray running, `dxcap -forcetdr`, wait 45 s, `gao --status` | yes | `applied:` equals the saved tune again; `boot.log` has `watchdog: ... re-applied`; a balloon said so | |
 | 34 | Watchdog backs off from another tool | tray running, set an offset in MSI Afterburner and Apply | no | a balloon says another program changed the settings; the watchdog does not fight it | |
 | 35 | One instance | start the app twice | no | the second start brings the first window forward and exits | Pass (2026-09-27, after the P5 fix pass): the second start exits with code 0, the first keeps running. |
-| 36 | CLI and tray side by side | tray running with the tune kept applied; `gao --reset`, wait 45 s, `gao --status`; then `gao --optimize` from a shell while the window runs an optimize | yes | after `--reset` the card stays at stock (the tray notes it and does not re-apply); the second optimize refuses with `another optimize is already running` | |
+| 36 | CLI and tray side by side | tray running with the tune kept applied; `gao --reset`, wait 45 s, `gao --status`; then `gao --optimize` from a shell while the window runs an optimize | yes | after `--reset` the card stays at stock (the tray notes it and does not re-apply); after `gao --apply` the tray keeps the tune applied again; the second optimize refuses with `another optimize is already running` | |
 | 37 | Closing the window | close the window with no tune applied, then again with a tune kept applied | no / yes | without a tune the app exits; with one it hides to the tray | Pass without a tune (2026-09-27): the app exits on close. |
 
 ## Notes

src/app/common.cpp

@@ -43,13 +43,14 @@ bool tuning_in_progress() {
     return r == WAIT_TIMEOUT;
 }
 
-unsigned stock_by_choice_message() {
-    static const UINT msg = RegisterWindowMessageW(L"GpuAutoOptimizer.StockByChoice");
+unsigned tray_notice_message() {
+    static const UINT msg = RegisterWindowMessageW(L"GpuAutoOptimizer.TrayNotice");
     return msg;
 }
 
-void tell_tray_stock_by_choice() {
-    if (const HWND tray = FindWindowW(kTrayWindowClass, nullptr)) PostMessageW(tray, stock_by_choice_message(), 0, 0);
+void tell_tray(TrayNotice notice) {
+    if (const HWND tray = FindWindowW(kTrayWindowClass, nullptr))
+        PostMessageW(tray, tray_notice_message(), static_cast<WPARAM>(notice), 0);
 }
 
 bool is_elevated() {

src/app/common.hpp

@@ -43,11 +43,13 @@ class TuningLock {
 // True while another thread or process holds the TuningLock.
 bool tuning_in_progress();
 
-// Tells a running tray app that the card was put back to stock on purpose
-// (gao --reset), so its watchdog must not re-apply the tune.
-void tell_tray_stock_by_choice();
-// The registered window message tell_tray_stock_by_choice() posts.
-unsigned stock_by_choice_message();
+// What the command line tells a running tray app, so its watchdog follows:
+// stock on purpose (gao --reset) stops it; the tune applied (gao --apply)
+// starts it again.
+enum class TrayNotice : unsigned { StockByChoice = 0, TuneApplied = 1 };
+void tell_tray(TrayNotice notice);
+// The registered window message tell_tray() posts; the notice is its wParam.
+unsigned tray_notice_message();
 
 struct OptimizeHooks {
     std::function<bool()> aborted;                        // polled between probes

src/app/gui/main_gui.cpp

@@ -55,7 +55,7 @@ struct App {
     HWND hwnd = nullptr;
     HANDLE instance_mutex = nullptr;
     UINT taskbar_created = 0;
-    UINT stock_by_choice = 0;
+    UINT tray_notice = 0;
     bool visible = false;
     bool exit_requested = false;
     int input_frames = 0;   // frames still to draw after input, so hover/click feedback shows
@@ -430,9 +430,15 @@ LRESULT CALLBACK wnd_proc(HWND hwnd, UINT msg, WPARAM wp, LPARAM lp) {
         tray_icon(NIM_ADD);
         return 0;
     }
-    if (msg == g.stock_by_choice && g.stock_by_choice) {   // gao --reset in a shell
-        g.watch = false;
-        g.ui.watchdog_note = gao::app::now_text() + "  Set to stock from the command line; not re-applied until you apply it again.";
+    if (msg == g.tray_notice && g.tray_notice) {   // gao --reset / gao --apply in a shell
+        if (wp == static_cast<WPARAM>(gao::app::TrayNotice::TuneApplied)) {
+            g.watch = true;
+            g.watchdog = gao::Watchdog();
+            g.ui.watchdog_note = gao::app::now_text() + "  Applied from the command line; kept applied from now on.";
+        } else {
+            g.watch = false;
+            g.ui.watchdog_note = gao::app::now_text() + "  Set to stock from the command line; not re-applied until you apply it again.";
+        }
         refresh_status(false);
         return 0;
     }
@@ -561,11 +567,11 @@ int WINAPI wWinMain(HINSTANCE inst, HINSTANCE, PWSTR cmdline, int) {
     DwmSetWindowAttribute(g.hwnd, DWMWA_USE_IMMERSIVE_DARK_MODE, &dark, sizeof(dark));
 
     // Explorer runs unelevated; let its tray notifications and a relaunch's
-    // "come forward" reach an elevated window. Not the stock-by-choice notice:
-    // gao --reset is always elevated, and an unelevated process must not be
-    // able to switch the watchdog off.
+    // "come forward" reach an elevated window. Not the command-line notices:
+    // gao --reset and --apply are always elevated, and an unelevated process
+    // must not be able to switch the watchdog on or off.
     g.taskbar_created = RegisterWindowMessageW(L"TaskbarCreated");
-    g.stock_by_choice = gao::app::stock_by_choice_message();
+    g.tray_notice = gao::app::tray_notice_message();
     for (UINT m : {WM_APP_TRAY, g.taskbar_created, WM_APP_SHOW})
         ChangeWindowMessageFilterEx(g.hwnd, m, MSGFLT_ALLOW, nullptr);
 

src/app/main.cpp

@@ -97,7 +97,7 @@ static int set_offset(const char* label, int mhz, bool core) {
 static int reset() {
     // Stock by choice: tell a running tray app first, or a watchdog tick
     // between the writes and the notice would take it for a TDR and re-apply.
-    gao::app::tell_tray_stock_by_choice();
+    gao::app::tell_tray(gao::app::TrayNotice::StockByChoice);
     gao::Nvapi nvapi;
     if (!nvapi.Init()) { std::printf("NVAPI init failed: %s\n", nvapi.Error().c_str()); return 1; }
     bool ok = nvapi.ResetOffsets(kGpu);
@@ -239,7 +239,7 @@ static int optimize(gao::Preset preset) {
     if (out.saved) std::printf("Saved: `gao --apply` re-applies it, `gao --boot on` applies it at every logon.\n");
     else std::printf("not saved: %s\n", out.save_note.c_str());
     std::printf("Applied until reboot. `gao --reset` returns to stock.\n");
-    return 0;
+    return out.saved ? 0 : 2;   // 2: tuned and applied, but --apply and boot-apply cannot use it
 }
 
 static int apply() {
@@ -260,6 +260,7 @@ static int apply() {
     }
     const gao::GpuControl gpu = gao::make_gpu_control(nvml, nvapi, kGpu);
     if (!gao::apply_profile(gpu, *cfg.profile, &why)) { std::printf("not applied: %s\n", why.c_str()); return 1; }
+    gao::app::tell_tray(gao::app::TrayNotice::TuneApplied);   // a running tray keeps it applied from now on
     std::printf("applied %s\nOK\n", gao::app::profile_text(*cfg.profile).c_str());
     return 0;
 }