vclptr: create Instance helpers, and set initial ref-count to 1.
Document that in README.lifecycle; the problem is that our constructors
currently take and release references left/right on the object being
created, which ... means we need an initial reference.
Change-Id: I5de952b73ac67888c3fbb150d4a7cde2a7bc9abf
diff --git a/include/rtl/ref.hxx b/include/rtl/ref.hxx
index 942923a..097584b 100644
--- a/include/rtl/ref.hxx
+++ b/include/rtl/ref.hxx
@@ -49,6 +49,13 @@ public:
/** Constructor...
*/
inline Reference (reference_type * pBody, __sal_NoAcquire)
: m_pBody (pBody)
{
}
/** Constructor...
*/
inline Reference (reference_type * pBody)
: m_pBody (pBody)
{
@@ -56,7 +63,6 @@ public:
m_pBody->acquire();
}
/** Copy constructor...
*/
inline Reference (const Reference<reference_type> & handle)
diff --git a/include/vcl/vclptr.hxx b/include/vcl/vclptr.hxx
index 6ab6373..0c29f11 100644
--- a/include/vcl/vclptr.hxx
+++ b/include/vcl/vclptr.hxx
@@ -22,6 +22,7 @@
#include <rtl/ref.hxx>
#include <cstddef>
#include <utility>
/// @cond INTERNAL
namespace vcl { namespace detail {
@@ -90,14 +91,12 @@ public:
: m_rInnerRef()
{}
/** Constructor...
*/
inline VclPtr (reference_type * pBody)
: m_rInnerRef(pBody)
{}
/** Copy constructor...
*/
inline VclPtr (const VclPtr<reference_type> & handle)
@@ -216,8 +215,31 @@ public:
{
return (m_rInnerRef > handle.m_rInnerRef);
}
protected:
inline VclPtr (reference_type * pBody, __sal_NoAcquire)
: m_rInnerRef(pBody, SAL_NO_ACQUIRE)
{}
}; // class VclPtr
/**
* A construction helper for VclPtr. Since VclPtr types are created
* with a reference-count of one - to help fit into the existing
* code-flow; this helps us to construct them easily.
*
* For more details on the design please see vcl/README.lifecycle
*
* @param reference_type must be a subclass of vcl::Window
*/
template <class reference_type>
class VclPtrInstance : public VclPtr<reference_type>
{
public:
template<typename... Arg> VclPtrInstance(Arg &&... arg)
: VclPtr<reference_type>( new reference_type(std::forward<Arg>(arg)...), SAL_NO_ACQUIRE )
{
}
};
template <class reference_type>
class ScopedVclPtr : public VclPtr<reference_type>
@@ -277,6 +299,30 @@ private:
ScopedVclPtr (const ScopedVclPtr<reference_type> &) SAL_DELETED_FUNCTION;
// And certainly we don't want a default assignment operator.
ScopedVclPtr<reference_type>& SAL_CALL operator= (const ScopedVclPtr<reference_type> &) SAL_DELETED_FUNCTION;
protected:
inline ScopedVclPtr (reference_type * pBody, __sal_NoAcquire)
: VclPtr<reference_type>(pBody, SAL_NO_ACQUIRE)
{}
};
/**
* A construction helper for ScopedVclPtr. Since VclPtr types are created
* with a reference-count of one - to help fit into the existing
* code-flow; this helps us to construct them easily.
*
* For more details on the design please see vcl/README.lifecycle
*
* @param reference_type must be a subclass of vcl::Window
*/
template <class reference_type>
class ScopedVclPtrInstance : public ScopedVclPtr<reference_type>
{
public:
template<typename... Arg> ScopedVclPtrInstance(Arg &&... arg)
: ScopedVclPtr<reference_type>( new reference_type(std::forward<Arg>(arg)...), SAL_NO_ACQUIRE )
{
}
};
#endif // INCLUDED_VCL_PTR_HXX
diff --git a/vcl/README.lifecycle b/vcl/README.lifecycle
index 26e7a34..6a9e080 100644
--- a/vcl/README.lifecycle
+++ b/vcl/README.lifecycle
@@ -45,8 +45,9 @@ to lingering pointers to freed objects.
to reduce code-thrash. VclPtr is used to wrap all OutputDevice
derived classes thus:
VclPtr<Dialog> pDialog( new Dialog( ... ) );
// gotcha - this is not a good idea ...
VclPtr<Dialog> pDialog( new Dialog( ... ), SAL_NO_ACQUIRE );
...
pDialog.disposeAndClear();
However - while the VclPtr reference count controls the
lifecycle of the Dialog object, it is necessary to be able to
@@ -84,30 +85,47 @@ to lingering pointers to freed objects.
Luckily it is easy to avoid that with a ScopedVclPtr which
does this for you when it goes out of scope.
** One extra gotcha - an initial reference-count of 1
In the normal world of love and sanity, eg. creating UNO
objects, the objects start with a ref-count of zero. Thus
the first reference is always taken after construction by
the surrounding smart pointer.
Unfortunately, the existing VCL code is somewhat tortured,
and does a lot of reference and de-reference action on the
class -during- construction. This forces us to construct with
a reference of 1 - and to hand that into the initial smart
pointer with a SAL_NO_ACQUIRE.
To make this easier, we have 'Instance' template wrappers
that make this apparently easier, by constructing the
pointer for you.
** How does my familiar code change ?
Lets tweak the exemplary code above to fit the new model:
- Dialog aDialog(...);
- Dialog aDialog(... dialog params ... );
- aDialog.Execute(...);
+ ScopedVclPtr<Dialog> pDialog(new Dialog(...));
+ ScopedVclPtrInstance<Dialog> pDialog(... dialog params ... );
+ pDialog->Execute(...); // VclPtr behaves much like a pointer
or:
- Dialog *pDialog = new Dialog(...);
+ VclPtr<Dialog> pDialog(newDialog(...));
- Dialog *pDialog = new Dialog(... dialog params ...);
+ VclPtrInstance<Dialog> pDialog(... dialog params ...);
pDialog->Execute(...);
- delete pDialog;
+ pDialog.disposeAndClear(); // done manually - replaces a delete
or:
- boost::shared_ptr<Dialog> xDialog(new pDialog());
+ ScopedVclPtr<Dialog> xDialog(new Dialog(...));
- boost::shared_ptr<Dialog> xDialog(new Dialog(...));
+ ScopedVclPtrInstance<Dialog> xDialog(...);
xDialog->Execute(...);
+ // depending how shared_ptr was shared perhaps
+ // someone else gets a VclPtr to xDialog
or:
- VirtualDevice aDev;
+ ScopedVclPtr<VirtualDevice> pDev(new VirtualDevice());
+ ScopedVclPtrInstance<VirtualDevice> pDev();
** Why are these 'disposeOnce' calls in destructors ?
diff --git a/vcl/qa/cppunit/lifecycle.cxx b/vcl/qa/cppunit/lifecycle.cxx
index 12b0a51..7c1b1c2 100644
--- a/vcl/qa/cppunit/lifecycle.cxx
+++ b/vcl/qa/cppunit/lifecycle.cxx
@@ -59,7 +59,11 @@ void LifecycleTest::testCast()
void LifecycleTest::testVirtualDevice()
{
VclPtr<VirtualDevice> pVDev = new VirtualDevice();
VclPtr<VirtualDevice> pVDev( new VirtualDevice() );
ScopedVclPtr<VirtualDevice> pVDev2( new VirtualDevice() );
VclPtrInstance<VirtualDevice> pVDev3;
VclPtrInstance<VirtualDevice> pVDev4( 1 );
CPPUNIT_ASSERT(!!pVDev && !!pVDev2 && !!pVDev3 && !!pVDev4);
}
void LifecycleTest::testMultiDispose()
@@ -99,8 +103,8 @@ void LifecycleTest::testIsolatedWidgets()
void LifecycleTest::testParentedWidgets()
{
VclPtr<WorkWindow> xWin(new WorkWindow((vcl::Window *)NULL,
WB_APP|WB_STDWORK));
ScopedVclPtrInstance<WorkWindow> xWin(new WorkWindow((vcl::Window *)NULL,
WB_APP|WB_STDWORK));
CPPUNIT_ASSERT(xWin.get() != NULL);
xWin->Show();
testWidgets(xWin);
@@ -129,7 +133,7 @@ void LifecycleTest::testChildDispose()
void LifecycleTest::testPostDispose()
{
VclPtr<WorkWindow> xWin(new WorkWindow((vcl::Window *)NULL, WB_STDWORK));
VclPtrInstance<WorkWindow> xWin((vcl::Window *)NULL, WB_STDWORK);
xWin->disposeOnce();
// check selected methods continue to work post-dispose
diff --git a/vcl/source/outdev/outdev.cxx b/vcl/source/outdev/outdev.cxx
index beee1b7..e42c8c5 100644
--- a/vcl/source/outdev/outdev.cxx
+++ b/vcl/source/outdev/outdev.cxx
@@ -82,7 +82,7 @@ namespace {
// Begin initializer and accessor public functions
OutputDevice::OutputDevice() :
mnRefCnt(0),
mnRefCnt(1), // cf. VclPtrInstance and README.lifecycle
maRegion(true),
maFillColor( COL_WHITE ),
maTextLineColor( COL_TRANSPARENT ),
diff --git a/vcl/source/window/dialog.cxx b/vcl/source/window/dialog.cxx
index 9ca9c30..e59ba30 100644
--- a/vcl/source/window/dialog.cxx
+++ b/vcl/source/window/dialog.cxx
@@ -1065,7 +1065,7 @@ void Dialog::GrabFocusToFirstControl()
void Dialog::GetDrawWindowBorder( sal_Int32& rLeftBorder, sal_Int32& rTopBorder, sal_Int32& rRightBorder, sal_Int32& rBottomBorder ) const
{
ScopedVclPtr<ImplBorderWindow> aImplWin( new ImplBorderWindow( (vcl::Window*)this, WB_BORDER|WB_STDWORK, BORDERWINDOW_STYLE_OVERLAP ) );
ScopedVclPtrInstance<ImplBorderWindow> aImplWin( (vcl::Window*)this, WB_BORDER|WB_STDWORK, BORDERWINDOW_STYLE_OVERLAP );
aImplWin->GetBorder( rLeftBorder, rTopBorder, rRightBorder, rBottomBorder );
}
diff --git a/vcl/source/window/menubarwindow.cxx b/vcl/source/window/menubarwindow.cxx
index 0f49c51..7c0bca7 100644
--- a/vcl/source/window/menubarwindow.cxx
+++ b/vcl/source/window/menubarwindow.cxx
@@ -60,7 +60,7 @@ void DecoToolBox::DataChanged( const DataChangedEvent& rDCEvt )
void DecoToolBox::calcMinSize()
{
ScopedVclPtr<ToolBox> aTbx( new ToolBox(GetParent()) );
ScopedVclPtrInstance<ToolBox> aTbx( GetParent() );
if( GetItemCount() == 0 )
{
ResMgr* pResMgr = ImplGetResMgr();
diff --git a/vcl/source/window/paint.cxx b/vcl/source/window/paint.cxx
index 0f05ded..1dd9b3a 100644
--- a/vcl/source/window/paint.cxx
+++ b/vcl/source/window/paint.cxx
@@ -1094,7 +1094,7 @@ void Window::ImplPaintToDevice( OutputDevice* i_pTargetOutDev, const Point& i_rP
mpWindowImpl->mbReallyVisible = bRVisible;
// paint metafile to VDev
VclPtr<VirtualDevice> pMaskedDevice = new VirtualDevice( *i_pTargetOutDev, 0, 0 );
VclPtrInstance<VirtualDevice> pMaskedDevice( *i_pTargetOutDev, 0, 0 );
pMaskedDevice->SetOutputSizePixel( GetOutputSizePixel() );
pMaskedDevice->EnableRTL( IsRTLEnabled() );
aMtf.WindStart();
diff --git a/vcl/source/window/printdlg.cxx b/vcl/source/window/printdlg.cxx
index 4ab06b6..f173ad3 100644
--- a/vcl/source/window/printdlg.cxx
+++ b/vcl/source/window/printdlg.cxx
@@ -624,13 +624,13 @@ PrintDialog::PrintDialog( vcl::Window* i_pParent, const std::shared_ptr<PrinterC
if( maJobPage.mpPrinters->GetEntryPos( aValue ) != LISTBOX_ENTRY_NOTFOUND )
{
maJobPage.mpPrinters->SelectEntry( aValue );
maPController->setPrinter( VclPtr<Printer>( new Printer( aValue ) ) );
maPController->setPrinter( VclPtrInstance<Printer>( aValue ) );
}
else
{
// fall back to default printer
maJobPage.mpPrinters->SelectEntry( Printer::GetDefaultPrinterName() );
maPController->setPrinter( VclPtr<Printer>( new Printer( Printer::GetDefaultPrinterName() ) ) );
maPController->setPrinter( VclPtrInstance<Printer>( Printer::GetDefaultPrinterName() ) );
}
}
// not printing to file
@@ -1521,7 +1521,7 @@ IMPL_LINK( PrintDialog, SelectHdl, ListBox*, pBox )
{
OUString aNewPrinter( pBox->GetSelectEntry() );
// set new printer
maPController->setPrinter( VclPtr<Printer>( new Printer( aNewPrinter ) ) );
maPController->setPrinter( VclPtrInstance<Printer>( aNewPrinter ) );
maPController->resetPrinterOptions( maOptionsPage.mpToFileBox->IsChecked() );
// update text fields
updatePrinterText();
diff --git a/vcl/source/window/toolbox.cxx b/vcl/source/window/toolbox.cxx
index 58ec924..b434061 100644
--- a/vcl/source/window/toolbox.cxx
+++ b/vcl/source/window/toolbox.cxx
@@ -4833,7 +4833,7 @@ Size ToolBox::CalcMinimumWindowSizePixel() const
else
{
// create dummy toolbox for measurements
VclPtr< ToolBox > pToolBox = new ToolBox( GetParent(), GetStyle() );
VclPtrInstance< ToolBox > pToolBox( GetParent(), GetStyle() );
// copy until first useful item
std::vector< ImplToolItem >::iterator it = mpData->m_aItems.begin();
diff --git a/vcl/unx/generic/printer/cupsmgr.cxx b/vcl/unx/generic/printer/cupsmgr.cxx
index daddd1a..d51f752 100644
--- a/vcl/unx/generic/printer/cupsmgr.cxx
+++ b/vcl/unx/generic/printer/cupsmgr.cxx
@@ -966,7 +966,7 @@ namespace
{
bool bRet = false;
ScopedVclPtr<RTSPWDialog> aDialog(new RTSPWDialog(rServer, rUserName, NULL));
ScopedVclPtrInstance<RTSPWDialog> aDialog(rServer, rUserName, nullptr);
if (aDialog->Execute())
{
rUserName = aDialog->getUserName();
diff --git a/vcl/unx/x11/x11sys.cxx b/vcl/unx/x11/x11sys.cxx
index 8cad695..6723c63 100644
--- a/vcl/unx/x11/x11sys.cxx
+++ b/vcl/unx/x11/x11sys.cxx
@@ -134,7 +134,7 @@ int X11SalSystem::ShowNativeDialog( const OUString& rTitle, const OUString& rMes
if( pSVData->mpIntroWindow )
pSVData->mpIntroWindow->Hide();
ScopedVclPtr<WarningBox> aWarn(new WarningBox(NULL, WB_STDWORK, rMessage) );
ScopedVclPtrInstance<WarningBox> aWarn(nullptr, WB_STDWORK, rMessage);
aWarn->SetText( rTitle );
aWarn->Clear();
diff --git a/vcl/workben/outdevgrind.cxx b/vcl/workben/outdevgrind.cxx
index d530748..da14e1a 100644
--- a/vcl/workben/outdevgrind.cxx
+++ b/vcl/workben/outdevgrind.cxx
@@ -898,7 +898,7 @@ sal_uInt16 GrindApp::Exception( sal_uInt16 nError )
int GrindApp::Main()
{
ScopedVclPtr<TestWindow> aWindow(new TestWindow);
ScopedVclPtrInstance<TestWindow> aWindow;
aWindow->Execute();
return 0;
}
