QtDBus: compile-optimize inline swap functions

Instead of using the overly-generic qSwap() monster, use

- qt_ptr_swap() for swapping raw pointers
- member-swap for swapping smart pointers and owning containers
- std::swap() for swapping scalars

In QtCore, this has proven to give a nice reduction in compile time
for Qt users, cf. b1b0c2970e.

Pick-to: 6.3 6.2
Task-number: QTBUG-97601
Change-Id: I2cb0dd3cef3a2923e7d08bb9d93c692308797e5b
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>

src/dbus/qdbusargument.h

@@ -81,7 +81,7 @@ public:
     QDBusArgument &operator=(const QDBusArgument &other);
     ~QDBusArgument();
 
-    void swap(QDBusArgument &other) noexcept { qSwap(d, other.d); }
+    void swap(QDBusArgument &other) noexcept { qt_ptr_swap(d, other.d); }
 
     // used for marshalling (Qt -> D-BUS)
     QDBusArgument &operator<<(uchar arg);

src/dbus/qdbusconnection.h

@@ -138,7 +138,7 @@ public:
     QDBusConnection &operator=(const QDBusConnection &other);
     ~QDBusConnection();
 
-    void swap(QDBusConnection &other) noexcept { qSwap(d, other.d); }
+    void swap(QDBusConnection &other) noexcept { qt_ptr_swap(d, other.d); }
 
     bool isConnected() const;
     QString baseService() const;

src/dbus/qdbuserror.h

@@ -112,9 +112,9 @@ public:
 
     void swap(QDBusError &other) noexcept
     {
-        qSwap(code,   other.code);
-        qSwap(msg,    other.msg);
-        qSwap(nm,     other.nm);
+        std::swap(code, other.code);
+        msg.swap(other.msg);
+        nm.swap(other.nm);
     }
 
     ErrorType type() const;

src/dbus/qdbusextratypes.h

@@ -64,7 +64,7 @@ public:
     inline explicit QDBusObjectPath(const QString &path);
     explicit QDBusObjectPath(QString &&p) : m_path(std::move(p)) { doCheck(); }
 
-    void swap(QDBusObjectPath &other) noexcept { qSwap(m_path, other.m_path); }
+    void swap(QDBusObjectPath &other) noexcept { m_path.swap(other.m_path); }
 
     inline void setPath(const QString &path);
 
@@ -119,7 +119,7 @@ public:
     inline explicit QDBusSignature(const QString &signature);
     explicit QDBusSignature(QString &&sig) : m_signature(std::move(sig)) { doCheck(); }
 
-    void swap(QDBusSignature &other) noexcept { qSwap(m_signature, other.m_signature); }
+    void swap(QDBusSignature &other) noexcept { m_signature.swap(other.m_signature); }
 
     inline void setSignature(const QString &signature);
 
@@ -169,7 +169,7 @@ public:
     inline explicit QDBusVariant(const QVariant &variant);
     explicit QDBusVariant(QVariant &&v) noexcept : m_variant(std::move(v)) {}
 
-    void swap(QDBusVariant &other) noexcept { qSwap(m_variant, other.m_variant); }
+    void swap(QDBusVariant &other) noexcept { m_variant.swap(other.m_variant); }
 
     inline void setVariant(const QVariant &variant);
 

src/dbus/qdbusmessage.h

@@ -71,7 +71,7 @@ public:
     QDBusMessage &operator=(const QDBusMessage &other);
     ~QDBusMessage();
 
-    void swap(QDBusMessage &other) noexcept { qSwap(d_ptr, other.d_ptr); }
+    void swap(QDBusMessage &other) noexcept { qt_ptr_swap(d_ptr, other.d_ptr); }
 
     static QDBusMessage createSignal(const QString &path, const QString &interface,
                                      const QString &name);

src/dbus/qdbuspendingcall.h

@@ -63,7 +63,7 @@ public:
     QDBusPendingCall &operator=(QDBusPendingCall &&other) noexcept { swap(other); return *this; }
     QDBusPendingCall &operator=(const QDBusPendingCall &other);
 
-    void swap(QDBusPendingCall &other) noexcept { qSwap(d, other.d); }
+    void swap(QDBusPendingCall &other) noexcept { d.swap(other.d); }
 
 #ifndef Q_CLANG_QDOC
     // pretend that they aren't here

src/dbus/qdbusunixfiledescriptor.h

@@ -64,7 +64,7 @@ public:
     ~QDBusUnixFileDescriptor();
 
     void swap(QDBusUnixFileDescriptor &other) noexcept
-    { qSwap(d, other.d); }
+    { d.swap(other.d); }
 
     bool isValid() const;