Make QMediaFormat movable

The d-pointer is only a reserved placeholder, but make it a
QExplicitlySharedDataPointer anyway. The default constructor just
initializes to zero, so the overhead is marginal, but makes it safe to
extend in the future if needed.

Change-Id: Ib6269f59b59af05647c0f9295ce634d5c327339e
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

2 files changed, 41 insertions, 6 deletions

diff --git a/src/multimedia/qmediaformat.cpp b/src/multimedia/qmediaformat.cpp
index 4c239e78f..ccf926026 100644
--- a/src/multimedia/qmediaformat.cpp
+++ b/src/multimedia/qmediaformat.cpp
@@ -67,6 +67,11 @@ const char *mimeTypeForFormat[QMediaFormat::LastFileFormat + 2] =
 
 }
 
+class QMediaFormatPrivate : public QSharedData
+{};
+
+QT_DEFINE_QESDP_SPECIALIZATION_DTOR(QMediaFormatPrivate);
+
 /*! \enum QMediaFormat::FileFormat
 
     Describes the container format used in a multimedia file or stream.
@@ -91,16 +96,39 @@ const char *mimeTypeForFormat[QMediaFormat::LastFileFormat + 2] =
 */
 
 // these are non inline to make a possible future addition of a d pointer binary compatible
+
+/*!
+    Constucts a QMediaFormat object for \a format.
+*/
 QMediaFormat::QMediaFormat(FileFormat format)
     : fmt(format)
 {
-    Q_UNUSED(d);
 }
 
+/*!
+    Destroys the QMediaFormat object.
+*/
 QMediaFormat::~QMediaFormat() = default;
-QMediaFormat::QMediaFormat(const QMediaFormat &other) = default;
-QMediaFormat &QMediaFormat::operator=(const QMediaFormat &other) = default;
 
+/*!
+    Constructs a QMediaFormat object by copying from \a other.
+*/
+QMediaFormat::QMediaFormat(const QMediaFormat &other) noexcept = default;
+
+/*!
+    Copies \a other into this QMediaFormat object.
+*/
+QMediaFormat &QMediaFormat::operator=(const QMediaFormat &other) noexcept = default;
+
+/*! \fn QMediaFormat::QMediaFormat(QMediaFormat &&other)
+
+    Constructs a QMediaFormat objects by moving from \a other.
+*/
+
+/*! \fn QMediaFormat &QMediaFormat::operator=(QMediaFormat &&other)
+
+    Moves \a other into this QMediaFormat objects.
+*/
 
 /*! \fn void QMediaFormat::setMediaContainer(QMediaFormat::FileFormat container)
 
diff --git a/src/multimedia/qmediaformat.h b/src/multimedia/qmediaformat.h
index addd25a51..c8bfaf6c5 100644
--- a/src/multimedia/qmediaformat.h
+++ b/src/multimedia/qmediaformat.h
@@ -50,6 +50,8 @@ class QMediaFormat;
 class QMediaEncoderSettings;
 class QMediaFormatPrivate;
 
+QT_DECLARE_QESDP_SPECIALIZATION_DTOR_WITH_EXPORT(QMediaFormatPrivate, Q_MULTIMEDIA_EXPORT)
+
 class Q_MULTIMEDIA_EXPORT QMediaFormat
 {
 public:
@@ -110,8 +112,13 @@ public:
 
     QMediaFormat(FileFormat format = UnspecifiedFormat);
     ~QMediaFormat();
-    QMediaFormat(const QMediaFormat &other);
-    QMediaFormat &operator=(const QMediaFormat &other);
+    QMediaFormat(const QMediaFormat &other) noexcept;
+    QMediaFormat &operator=(const QMediaFormat &other) noexcept;
+
+    QMediaFormat(QMediaFormat &&other) noexcept = default;
+    QT_MOVE_ASSIGNMENT_OPERATOR_IMPL_VIA_PURE_SWAP(QMediaFormat)
+    void swap(QMediaFormat &other) noexcept
+    { qSwap(d, other.d); }
 
     FileFormat format() const { return fmt; }
     void setFormat(FileFormat f) { fmt = f; }
@@ -147,7 +154,7 @@ protected:
     FileFormat fmt;
     AudioCodec audio = AudioCodec::Unspecified;
     VideoCodec video = VideoCodec::Unspecified;
-    QMediaFormatPrivate *d = nullptr;
+    QExplicitlySharedDataPointer<QMediaFormatPrivate> d;
 };
 
 QT_END_NAMESPACE