Q{File,Font,Color,Message}DialogOptions are no value classes

These classes are only held in QSharedPointer, so optimize for that:

1. Disable default ctor, copy ctor and assignment operator,
   destructor and swap for public users.
2. Add create() to return an instance in a shared pointer.
3. Allocate public and private classes in one memory block,
   use QSharedPointer::create() to also add the QSharedPointer
   control block to the same memory allocation.

As a consequence, this reduces the creation of a Q*DialogOptions
into a shared pointer by two memory allocations.

Add a macro to enable atomic updates to QtQuick and other users
outside QtBase.

[ChangeLog][QtGui]
[QFileDialogOptions/QFontDialogOptions/QMessageDialogOptions/QColorDialogOptions]
This class no longer has value semantics, but needs to be held
in QSharedPointer (as it always was). To copy an instance, use
the clone() method.

Change-Id: I4c81220e0a8286a310df1c224a30eca34824c4e6
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@theqtcompany.com>
Reviewed-by: Lars Knoll <lars.knoll@theqtcompany.com>
Reviewed-by: Shawn Rutledge <shawn.rutledge@theqtcompany.com>

1 files changed, 33 insertions, 36 deletions

diff --git a/src/gui/kernel/qplatformdialoghelper.h b/src/gui/kernel/qplatformdialoghelper.h
index 825dcf293d..78667643fe 100644
--- a/src/gui/kernel/qplatformdialoghelper.h
+++ b/src/gui/kernel/qplatformdialoghelper.h
@@ -72,6 +72,8 @@ class QFontDialogOptionsPrivate;
 class QFileDialogOptionsPrivate;
 class QMessageDialogOptionsPrivate;
 
+#define QPLATFORMDIALOGHELPERS_HAS_CREATE
+
 class Q_GUI_EXPORT QPlatformDialogHelper : public QObject
 {
     Q_OBJECT
@@ -176,6 +178,10 @@ QT_BEGIN_NAMESPACE
 class Q_GUI_EXPORT QColorDialogOptions
 {
     Q_GADGET
+    Q_DISABLE_COPY(QColorDialogOptions)
+protected:
+    explicit QColorDialogOptions(QColorDialogOptionsPrivate *dd);
+    ~QColorDialogOptions();
 public:
     enum ColorDialogOption {
         ShowAlphaChannel    = 0x00000001,
@@ -186,12 +192,8 @@ public:
     Q_DECLARE_FLAGS(ColorDialogOptions, ColorDialogOption)
     Q_FLAG(ColorDialogOptions)
 
-    QColorDialogOptions();
-    QColorDialogOptions(const QColorDialogOptions &rhs);
-    QColorDialogOptions &operator=(const QColorDialogOptions &rhs);
-    ~QColorDialogOptions();
-
-    void swap(QColorDialogOptions &other) { qSwap(d, other.d); }
+    static QSharedPointer<QColorDialogOptions> create();
+    QSharedPointer<QColorDialogOptions> clone() const;
 
     QString windowTitle() const;
     void setWindowTitle(const QString &);
@@ -211,11 +213,9 @@ public:
     static void setStandardColor(int index, QRgb color);
 
 private:
-    QSharedDataPointer<QColorDialogOptionsPrivate> d;
+    QColorDialogOptionsPrivate *d;
 };
 
-Q_DECLARE_SHARED(QColorDialogOptions)
-
 class Q_GUI_EXPORT QPlatformColorDialogHelper : public QPlatformDialogHelper
 {
     Q_OBJECT
@@ -237,6 +237,11 @@ private:
 class Q_GUI_EXPORT QFontDialogOptions
 {
     Q_GADGET
+    Q_DISABLE_COPY(QFontDialogOptions)
+protected:
+    explicit QFontDialogOptions(QFontDialogOptionsPrivate *dd);
+    ~QFontDialogOptions();
+
 public:
     enum FontDialogOption {
         NoButtons           = 0x00000001,
@@ -250,12 +255,8 @@ public:
     Q_DECLARE_FLAGS(FontDialogOptions, FontDialogOption)
     Q_FLAG(FontDialogOptions)
 
-    QFontDialogOptions();
-    QFontDialogOptions(const QFontDialogOptions &rhs);
-    QFontDialogOptions &operator=(const QFontDialogOptions &rhs);
-    ~QFontDialogOptions();
-
-    void swap(QFontDialogOptions &other) { qSwap(d, other.d); }
+    static QSharedPointer<QFontDialogOptions> create();
+    QSharedPointer<QFontDialogOptions> clone() const;
 
     QString windowTitle() const;
     void setWindowTitle(const QString &);
@@ -266,11 +267,9 @@ public:
     FontDialogOptions options() const;
 
 private:
-    QSharedDataPointer<QFontDialogOptionsPrivate> d;
+    QFontDialogOptionsPrivate *d;
 };
 
-Q_DECLARE_SHARED(QFontDialogOptions)
-
 class Q_GUI_EXPORT QPlatformFontDialogHelper : public QPlatformDialogHelper
 {
     Q_OBJECT
@@ -292,6 +291,11 @@ private:
 class Q_GUI_EXPORT QFileDialogOptions
 {
     Q_GADGET
+    Q_DISABLE_COPY(QFileDialogOptions)
+protected:
+    QFileDialogOptions(QFileDialogOptionsPrivate *dd);
+    ~QFileDialogOptions();
+
 public:
     enum ViewMode { Detail, List };
     Q_ENUM(ViewMode)
@@ -319,12 +323,8 @@ public:
     Q_DECLARE_FLAGS(FileDialogOptions, FileDialogOption)
     Q_FLAG(FileDialogOptions)
 
-    QFileDialogOptions();
-    QFileDialogOptions(const QFileDialogOptions &rhs);
-    QFileDialogOptions &operator=(const QFileDialogOptions &rhs);
-    ~QFileDialogOptions();
-
-    void swap(QFileDialogOptions &other) { qSwap(d, other.d); }
+    static QSharedPointer<QFileDialogOptions> create();
+    QSharedPointer<QFileDialogOptions> clone() const;
 
     QString windowTitle() const;
     void setWindowTitle(const QString &);
@@ -383,11 +383,9 @@ public:
     static QString defaultNameFilterString();
 
 private:
-    QSharedDataPointer<QFileDialogOptionsPrivate> d;
+    QFileDialogOptionsPrivate *d;
 };
 
-Q_DECLARE_SHARED(QFileDialogOptions)
-
 class Q_GUI_EXPORT QPlatformFileDialogHelper : public QPlatformDialogHelper
 {
     Q_OBJECT
@@ -423,17 +421,18 @@ private:
 class Q_GUI_EXPORT QMessageDialogOptions
 {
     Q_GADGET
+    Q_DISABLE_COPY(QMessageDialogOptions)
+protected:
+    QMessageDialogOptions(QMessageDialogOptionsPrivate *dd);
+    ~QMessageDialogOptions();
+
 public:
     // Keep in sync with QMessageBox::Icon
     enum Icon { NoIcon, Information, Warning, Critical, Question };
     Q_ENUM(Icon)
 
-    QMessageDialogOptions();
-    QMessageDialogOptions(const QMessageDialogOptions &rhs);
-    QMessageDialogOptions &operator=(const QMessageDialogOptions &rhs);
-    ~QMessageDialogOptions();
-
-    void swap(QMessageDialogOptions &other) { qSwap(d, other.d); }
+    static QSharedPointer<QMessageDialogOptions> create();
+    QSharedPointer<QMessageDialogOptions> clone() const;
 
     QString windowTitle() const;
     void setWindowTitle(const QString &);
@@ -454,11 +453,9 @@ public:
     QPlatformDialogHelper::StandardButtons standardButtons() const;
 
 private:
-    QSharedDataPointer<QMessageDialogOptionsPrivate> d;
+    QMessageDialogOptionsPrivate *d;
 };
 
-Q_DECLARE_SHARED(QMessageDialogOptions)
-
 class Q_GUI_EXPORT QPlatformMessageDialogHelper : public QPlatformDialogHelper
 {
     Q_OBJECT