QEventDispatcherWin32: Use a shared class name for the message window.

Introduce a global-static struct storing atom and class name for
the message window to be shared between threads. This prevents
RegisterWindow()/UnregisterWindow() of different threads (using exec())
from interfering and silently failing.

Task-number: QTBUG-39471
Change-Id: I9bc1106a41f64749c55825a96973921bb831458f
Reviewed-by: Joerg Bornemann <joerg.bornemann@digia.com>
This commit is contained in:
Friedemann Kleint 2014-06-06 14:26:26 +02:00
parent 54a2206bba
commit feda990ae8

View File

@ -325,8 +325,6 @@ QEventDispatcherWin32Private::~QEventDispatcherWin32Private()
{ {
if (internalHwnd) if (internalHwnd)
DestroyWindow(internalHwnd); DestroyWindow(internalHwnd);
QString className = QLatin1String("QEventDispatcherWin32_Internal_Widget") + QString::number(quintptr(qt_internal_proc));
UnregisterClass((wchar_t*)className.utf16(), qWinAppInst());
} }
void QEventDispatcherWin32Private::activateEventNotifier(QWinEventNotifier * wen) void QEventDispatcherWin32Private::activateEventNotifier(QWinEventNotifier * wen)
@ -486,10 +484,26 @@ LRESULT QT_WIN_CALLBACK qt_GetMessageHook(int code, WPARAM wp, LPARAM lp)
#endif #endif
} }
static HWND qt_create_internal_window(const QEventDispatcherWin32 *eventDispatcher) // Provide class name and atom for the message window used by
// QEventDispatcherWin32Private via Q_GLOBAL_STATIC shared between threads.
struct QWindowsMessageWindowClassContext
{
QWindowsMessageWindowClassContext();
~QWindowsMessageWindowClassContext();
ATOM atom;
wchar_t *className;
};
QWindowsMessageWindowClassContext::QWindowsMessageWindowClassContext()
: atom(0), className(0)
{ {
// make sure that multiple Qt's can coexist in the same process // make sure that multiple Qt's can coexist in the same process
QString className = QLatin1String("QEventDispatcherWin32_Internal_Widget") + QString::number(quintptr(qt_internal_proc)); const QString qClassName = QStringLiteral("QEventDispatcherWin32_Internal_Widget")
+ QString::number(quintptr(qt_internal_proc));
className = new wchar_t[qClassName.size() + 1];
qClassName.toWCharArray(className);
className[qClassName.size()] = 0;
WNDCLASS wc; WNDCLASS wc;
wc.style = 0; wc.style = 0;
@ -501,16 +515,37 @@ static HWND qt_create_internal_window(const QEventDispatcherWin32 *eventDispatch
wc.hCursor = 0; wc.hCursor = 0;
wc.hbrBackground = 0; wc.hbrBackground = 0;
wc.lpszMenuName = NULL; wc.lpszMenuName = NULL;
wc.lpszClassName = reinterpret_cast<const wchar_t *> (className.utf16()); wc.lpszClassName = className;
atom = RegisterClass(&wc);
if (!atom) {
qErrnoWarning("%s: RegisterClass() failed", Q_FUNC_INFO, qPrintable(qClassName));
delete [] className;
className = 0;
}
}
RegisterClass(&wc); QWindowsMessageWindowClassContext::~QWindowsMessageWindowClassContext()
{
if (className) {
UnregisterClass(className, qWinAppInst());
delete [] className;
}
}
Q_GLOBAL_STATIC(QWindowsMessageWindowClassContext, qWindowsMessageWindowClassContext)
static HWND qt_create_internal_window(const QEventDispatcherWin32 *eventDispatcher)
{
QWindowsMessageWindowClassContext *ctx = qWindowsMessageWindowClassContext();
if (!ctx->atom)
return 0;
#ifdef Q_OS_WINCE #ifdef Q_OS_WINCE
HWND parent = 0; HWND parent = 0;
#else #else
HWND parent = HWND_MESSAGE; HWND parent = HWND_MESSAGE;
#endif #endif
HWND wnd = CreateWindow(wc.lpszClassName, // classname HWND wnd = CreateWindow(ctx->className, // classname
wc.lpszClassName, // window name ctx->className, // window name
0, // style 0, // style
0, 0, 0, 0, // geometry 0, 0, 0, 0, // geometry
parent, // parent parent, // parent
@ -519,7 +554,8 @@ static HWND qt_create_internal_window(const QEventDispatcherWin32 *eventDispatch
0); // windows creation data. 0); // windows creation data.
if (!wnd) { if (!wnd) {
qWarning("QEventDispatcher: Failed to create QEventDispatcherWin32 internal window: %d\n", (int)GetLastError()); qErrnoWarning("%s: CreateWindow() for QEventDispatcherWin32 internal window failed", Q_FUNC_INFO);
return 0;
} }
#ifdef GWLP_USERDATA #ifdef GWLP_USERDATA