QWin32PrintEnginePrivate: Properly initialize flags and fields of DEVMODE

- Set the respective flags of dmFields in
  QWin32PrintEngine::setProperty()
- Properly initialize newly allocated structs

This is merely for completeness, the allocation code paths are
not currently hit since the DEVMODE from the current printer is
used, which also has most dmFields bits set.

Pick-to: 6.6
Task-number: QTBUG-114604
Change-Id: I880d9faef9b1d491db4accd53d0d75b718f7f244
Reviewed-by: Oliver Wolff <oliver.wolff@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
Reviewed-by: Wladimir Leuschner <wladimir.leuschner@qt.io>

3 files changed, 19 insertions, 0 deletions

diff --git a/src/printsupport/dialogs/qpagesetupdialog_win.cpp b/src/printsupport/dialogs/qpagesetupdialog_win.cpp
index 8e735369b2..0f3011a638 100644
--- a/src/printsupport/dialogs/qpagesetupdialog_win.cpp
+++ b/src/printsupport/dialogs/qpagesetupdialog_win.cpp
@@ -135,6 +135,7 @@ int QPageSetupDialog::exec()
             if (ep->ownsDevMode && ep->devMode)
                 free(ep->devMode);
             ep->devMode = reinterpret_cast<DEVMODE *>(malloc(devModeSize));
+            QWin32PrintEnginePrivate::initializeDevMode(ep->devMode);
             ep->ownsDevMode = true;
 
             // Copy
diff --git a/src/printsupport/platform/windows/qprintengine_win.cpp b/src/printsupport/platform/windows/qprintengine_win.cpp
index 753b60153e..b275b01990 100644
--- a/src/printsupport/platform/windows/qprintengine_win.cpp
+++ b/src/printsupport/platform/windows/qprintengine_win.cpp
@@ -877,6 +877,7 @@ void QWin32PrintEnginePrivate::initialize()
         LONG result = DocumentProperties(nullptr, hPrinter, lpwPrinterName,
                                          nullptr, nullptr, 0);
         devMode = reinterpret_cast<DEVMODE *>(malloc(result));
+        initializeDevMode(devMode);
         ownsDevMode = true;
 
          // Get the default DevMode
@@ -916,6 +917,13 @@ void QWin32PrintEnginePrivate::initialize()
 #endif // QT_DEBUG_DRAW || QT_DEBUG_METRICS
 }
 
+void QWin32PrintEnginePrivate::initializeDevMode(DEVMODE *devMode)
+{
+    memset(devMode, 0, sizeof(DEVMODE));
+    devMode->dmSize = sizeof(DEVMODE);
+    devMode->dmSpecVersion = DM_SPECVERSION;
+}
+
 void QWin32PrintEnginePrivate::initHDC()
 {
     Q_ASSERT(hdc);
@@ -1055,6 +1063,7 @@ void QWin32PrintEngine::setProperty(PrintEnginePropertyKey key, const QVariant &
             if (!d->devMode)
                 break;
             d->devMode->dmCollate = value.toBool() ? DMCOLLATE_TRUE : DMCOLLATE_FALSE;
+            d->devMode->dmFields |= DM_COLLATE;
             d->doReinit();
         }
         break;
@@ -1064,6 +1073,7 @@ void QWin32PrintEngine::setProperty(PrintEnginePropertyKey key, const QVariant &
             if (!d->devMode)
                 break;
             d->devMode->dmColor = (value.toInt() == QPrinter::Color) ? DMCOLOR_COLOR : DMCOLOR_MONOCHROME;
+            d->devMode->dmFields |= DM_COLOR;
             d->doReinit();
         }
         break;
@@ -1089,15 +1099,19 @@ void QWin32PrintEngine::setProperty(PrintEnginePropertyKey key, const QVariant &
         switch (mode) {
         case QPrint::DuplexNone:
             d->devMode->dmDuplex = DMDUP_SIMPLEX;
+            d->devMode->dmFields |= DM_DUPLEX;
             break;
         case QPrint::DuplexAuto:
             d->devMode->dmDuplex = d->m_pageLayout.orientation() == QPageLayout::Landscape ? DMDUP_HORIZONTAL : DMDUP_VERTICAL;
+            d->devMode->dmFields |= DM_DUPLEX;
             break;
         case QPrint::DuplexLongSide:
             d->devMode->dmDuplex = DMDUP_VERTICAL;
+            d->devMode->dmFields |= DM_DUPLEX;
             break;
         case QPrint::DuplexShortSide:
             d->devMode->dmDuplex = DMDUP_HORIZONTAL;
+            d->devMode->dmFields |= DM_DUPLEX;
             break;
         default:
             // Don't change
@@ -1125,6 +1139,7 @@ void QWin32PrintEngine::setProperty(PrintEnginePropertyKey key, const QVariant &
             break;
         d->num_copies = value.toInt();
         d->devMode->dmCopies = d->num_copies;
+        d->devMode->dmFields |= DM_COPIES;
         d->doReinit();
         break;
 
@@ -1133,6 +1148,7 @@ void QWin32PrintEngine::setProperty(PrintEnginePropertyKey key, const QVariant &
             break;
         QPageLayout::Orientation orientation = QPageLayout::Orientation(value.toInt());
         d->devMode->dmOrientation = orientation == QPageLayout::Landscape ? DMORIENT_LANDSCAPE : DMORIENT_PORTRAIT;
+        d->devMode->dmFields |= DM_ORIENTATION;
         d->m_pageLayout.setOrientation(orientation);
         d->updateMetrics();
         d->doReinit();
diff --git a/src/printsupport/platform/windows/qprintengine_win_p.h b/src/printsupport/platform/windows/qprintengine_win_p.h
index f9b5e77c28..995c31ff1e 100644
--- a/src/printsupport/platform/windows/qprintengine_win_p.h
+++ b/src/printsupport/platform/windows/qprintengine_win_p.h
@@ -111,6 +111,8 @@ public:
        is handled in the next begin or newpage. */
     void doReinit();
 
+    static void initializeDevMode(DEVMODE *);
+
     bool resetDC();
 
     void strokePath(const QPainterPath &path, const QColor &color);