[Installer] End a launcher that has no window to ask instead of prompting (#7681)

* [Installer] End a launcher that has no window to ask instead of prompting

The in-app updater starts this installer detached and then closes itself. A
client that accepts that close hides its window before it exits, and if it
then hangs in shutdown there is nothing left to ask: the holder probe
deliberately never posts WM_CLOSE to an instance it cannot see a window for,
so the "ask it to close again" answer only repeated itself until the user
picked Cancel and the installation aborted (Sentry COCKATRICE-DESKTOP-J).

The launcher wait now asks the launcher itself before asking the user. A new
probe mode, --close-launcher, answers whether that one process has a window a
close could reach at all; it is limited to a pid that still runs from the
directory being replaced, so a reused process id cannot be hit. When there is
no window, the installer gives the shutdown it already started one full grace
and then ends it through the handle it waited on, which is what the dialog's
Yes answer did. The prompt remains for the case it exists for: a window is up,
the instance may be waiting on its own question, and No now means only "keep
waiting".

The client is left alone: an already-installed version runs the installer
during its own update, so a change there cannot reach the run that aborts.

* [libcockatrice_rng] Include immintrin.h for AVX2 builds in SFMT

---------

Co-authored-by: sentry[bot] <39604003+sentry[bot]@users.noreply.github.com>

tools/installer-holder-probe/close_holders.cpp

@@ -15,8 +15,6 @@
 
 namespace
 {
-constexpr wchar_t COCKATRICE_IMAGE[] = L"cockatrice.exe";
-
 /// How long one poll of the asked processes takes. One WaitForSingleObject per process
 /// and no enumeration, so polling costs nothing next to the seconds this is called on.
 constexpr unsigned long WAIT_POLL_MILLISECONDS = 200;
@@ -26,11 +24,6 @@ constexpr unsigned long WAIT_POLL_MILLISECONDS = 200;
 /// the line stays far below it.
 constexpr std::size_t REPORT_CHAR_MAX = 900;
 
-bool isCockatriceImage(const std::wstring &imageName)
-{
-    return CompareStringOrdinal(imageName.c_str(), -1, COCKATRICE_IMAGE, -1, TRUE) == CSTR_EQUAL;
-}
-
 /// The holder as the log has to name it to be actionable. Deliberately not
 /// formatHolder(): that one is worded for the dialog, where ", running" says something
 /// the line here continues after.
@@ -112,7 +105,7 @@ struct CloseTarget
 {
     HWND main = nullptr;    ///< first visible window without an owner: the application's own
     HWND toRaise = nullptr; ///< topmost visible window: a dialog when one is up
-    bool modalOpen = false; ///< the window a close would reach is disabled, so a dialog of its own is up
+    bool modalOpen = false; ///< the only window a user could answer is the instance's own question
 };
 
 /// Only the windows the user could answer are candidates - see isAnswerableWindow. An
@@ -136,9 +129,11 @@ CloseTarget chooseCloseTarget(const std::vector<HWND> &windows)
     }
     target.toRaise = topmost != nullptr ? topmost : target.main;
     // A modal dialog disables the windows behind it, so a disabled main window is the
-    // instance asking a question of its own.
-    target.modalOpen =
-        target.toRaise != nullptr && IsWindowEnabled(target.main != nullptr ? target.main : target.toRaise) == FALSE;
+    // instance asking a question of its own. A visible window with no unowned main window
+    // next to it is one too: what is on screen is then the question itself - the window
+    // behind it is hidden, not gone - and there is no window a close could be posted to
+    // without hiding the question with it.
+    target.modalOpen = target.toRaise != nullptr && (target.main == nullptr || IsWindowEnabled(target.main) == FALSE);
     return target;
 }
 
@@ -213,6 +208,12 @@ bool waitForExit(const std::vector<HANDLE> &processes, unsigned long waitMillise
 }
 } // namespace
 
+bool isCockatriceImage(const std::wstring &imageName)
+{
+    constexpr wchar_t COCKATRICE_IMAGE[] = L"cockatrice.exe";
+    return CompareStringOrdinal(imageName.c_str(), -1, COCKATRICE_IMAGE, -1, TRUE) == CSTR_EQUAL;
+}
+
 CloseHoldersResult closeCockatriceHolders(const std::vector<Holder> &holders, unsigned long waitMilliseconds)
 {
     CloseHoldersResult result;
@@ -233,18 +234,20 @@ CloseHoldersResult closeCockatriceHolders(const std::vector<Holder> &holders, un
         search.processId = holder.processId;
         EnumWindows(collectProcessWindow, reinterpret_cast<LPARAM>(&search));
         if (search.windows.empty()) {
+            ++result.withoutWindow;
             lines.push_back(processLabel(holder) + L" has no window to close, left to you");
             continue;
         }
 
         const CloseTarget target = chooseCloseTarget(search.windows);
-        if (target.main == nullptr) {
+        if (target.toRaise == nullptr) {
             // Nothing visible that a user could answer: the instance is hidden - in the
             // notification area, say - or has nothing but Qt's own bookkeeping windows on
             // screen. Neither is a window a close could reach, and showing one from here does
             // not help: Windows would display it while the application still believes it is
             // hidden, so it stays blank and answers nothing. The instance is named and left to
             // the user, who can open it from the notification area.
+            ++result.withoutWindow;
             lines.push_back(processLabel(holder) + L" has no window to ask, left to you");
             continue;
         }
@@ -255,7 +258,8 @@ CloseHoldersResult closeCockatriceHolders(const std::vector<Holder> &holders, un
         // an earlier attempt useless: the client accepts it, hides this window and the dialog
         // with it, and stays alive inside the nested loop the dialog opened, where nothing can
         // reach it any more. The question is the request now, so it is brought forward and
-        // left alone.
+        // left alone - including a question whose owner window is hidden, which is the only
+        // thing left on screen and has no unowned window a close could be posted to.
         if (target.modalOpen) {
             lines.push_back(line + L", and is waiting for an answer to a question of its own");
             continue;