1 files changed, 74 insertions, 0 deletions
diff --git a/src/plugins/multimedia/ffmpeg/qwincapturablewindows.cpp b/src/plugins/multimedia/ffmpeg/qwincapturablewindows.cpp
new file mode 100644
index 000000000..aac77aec4
--- /dev/null
+++ b/src/plugins/multimedia/ffmpeg/qwincapturablewindows.cpp
@@ -0,0 +1,74 @@
+// Copyright (C) 2023 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
+
+#include "qwincapturablewindows_p.h"
+#include "private/qcapturablewindow_p.h"
+
+#include <qt_windows.h>
+
+QT_BEGIN_NAMESPACE
+
+static bool isTopLevelWindow(HWND hwnd)
+{
+    return hwnd && ::GetAncestor(hwnd, GA_ROOT) == hwnd;
+}
+
+static bool canCaptureWindow(HWND hwnd)
+{
+    Q_ASSERT(hwnd);
+
+    if (!::IsWindowVisible(hwnd))
+        return false;
+
+    RECT rect{};
+    if (!::GetWindowRect(hwnd, &rect))
+        return false;
+
+    if (rect.left >= rect.right || rect.top >= rect.bottom)
+        return false;
+
+    return true;
+}
+
+static QString windowTitle(HWND hwnd) {
+    // QTBUG-114890
+    // TODO: investigate the case when hwnd is inner and belows to another thread.
+    // It might causes deadlocks in specific cases.
+    auto titleLength = ::GetWindowTextLengthW(hwnd);
+    std::wstring buffer(titleLength + 1, L'\0');
+    titleLength = ::GetWindowTextW(hwnd, buffer.data(), titleLength + 1);
+    buffer.resize(titleLength);
+
+    return QString::fromStdWString(buffer);
+}
+
+QList<QCapturableWindow> QWinCapturableWindows::windows() const
+{
+    QList<QCapturableWindow> result;
+
+    auto windowHandler = [](HWND hwnd, LPARAM lParam) {
+        if (!canCaptureWindow(hwnd))
+            return TRUE; // Ignore window and continue enumerating
+
+        auto& windows = *reinterpret_cast<QList<QCapturableWindow>*>(lParam);
+
+        auto windowData = std::make_unique<QCapturableWindowPrivate>();
+        windowData->id = reinterpret_cast<QCapturableWindowPrivate::Id>(hwnd);
+        windowData->description = windowTitle(hwnd);
+        windows.push_back(windowData.release()->create());
+
+        return TRUE;
+    };
+
+    ::EnumWindows(windowHandler, reinterpret_cast<LPARAM>(&result));
+
+    return result;
+}
+
+bool QWinCapturableWindows::isWindowValid(const QCapturableWindowPrivate &window) const
+{
+    const auto hwnd = reinterpret_cast<HWND>(window.id);
+    return isTopLevelWindow(hwnd) && canCaptureWindow(hwnd);
+}
+
+QT_END_NAMESPACE