remove mpThreadGraphics from GDI backend

we have required for a long time now that all vcl/UI updates
run with the SolarMutex locked, so they are all effectively
single-threaded.

Change-Id: I4a0ce64a5fa9cb563d04f581cf3aa6e6e51ba1c1
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/181811
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>
Tested-by: Jenkins

4 files changed, 9 insertions, 101 deletions

diff --git a/vcl/inc/win/saldata.hxx b/vcl/inc/win/saldata.hxx
index 4ab4e2c0401a..6a00566cca31 100644
--- a/vcl/inc/win/saldata.hxx
+++ b/vcl/inc/win/saldata.hxx
@@ -115,7 +115,6 @@ public:
     sal_uInt16              mnStockPenCount;        // count of static pens
     sal_uInt16              mnStockBrushCount;      // count of static brushes
     WPARAM                  mnSalObjWantKeyEvt;     // KeyEvent that should be processed by SalObj-Hook
-    BYTE                    mnCacheDCInUse;         // count of CacheDC in use
     bool                    mbObjClassInit;         // is SALOBJECTCLASS initialised
     DWORD                   mnAppThreadId;          // Id from Application-Thread
     SalIcon*                mpFirstIcon;            // icon cache, points to first icon, NULL if none
@@ -204,8 +203,6 @@ OUString ImplSalGetUniString(const char* pStr, sal_Int32 nLen = -1);
 #define SAL_MSG_CREATEOBJECT        (WM_USER+116)
 // wParam == 0; lParam == pObject;
 #define SAL_MSG_DESTROYOBJECT       (WM_USER+117)
-// wParam == hWnd; lParam == 0; lResult == hDC
-#define SAL_MSG_GETCACHEDDC         (WM_USER+120)
 // wParam == hWnd; lParam == 0
 #define SAL_MSG_RELEASEDC           (WM_USER+121)
 // wParam == newParentHwnd; lParam == oldHwnd; lResult == newhWnd
diff --git a/vcl/inc/win/salframe.h b/vcl/inc/win/salframe.h
index ada7f2f022fe..fdf1b98a9873 100644
--- a/vcl/inc/win/salframe.h
+++ b/vcl/inc/win/salframe.h
@@ -41,7 +41,6 @@ public:
     HCURSOR                 mhCursor;               // cursor handle
     HIMC                    mhDefIMEContext;        // default IME-Context
     WinSalGraphics*         mpLocalGraphics;        // current main thread frame graphics
-    WinSalGraphics*         mpThreadGraphics;       // current frame graphics for other threads (DCX_CACHE)
     WinSalFrame*            mpNextFrame;            // pointer to next frame
     HMENU                   mSelectedhMenu;         // the menu where highlighting is currently going on
     HMENU                   mLastActivatedhMenu;    // the menu that was most recently opened
diff --git a/vcl/win/app/salinst.cxx b/vcl/win/app/salinst.cxx
index 0a8f33c06f0c..ccbbefa89ad6 100644
--- a/vcl/win/app/salinst.cxx
+++ b/vcl/win/app/salinst.cxx
@@ -271,7 +271,6 @@ SalData::SalData()
     mnStockPenCount = 0;        // count of static pens
     mnStockBrushCount = 0;      // count of static brushes
     mnSalObjWantKeyEvt = 0;     // KeyEvent for the SalObj hook
-    mnCacheDCInUse = 0;         // count of CacheDC in use
     mbObjClassInit = false;     // is SALOBJECTCLASS initialised
     mnAppThreadId = 0;          // Id from Application-Thread
     mpFirstIcon = nullptr;      // icon cache, points to first icon, NULL if none
@@ -668,13 +667,6 @@ LRESULT CALLBACK SalComWndProc( HWND, UINT nMsg, WPARAM wParam, LPARAM lParam, b
                 delete reinterpret_cast<SalObject*>(lParam);
             }
             break;
-        case (SAL_MSG_GETCACHEDDC):
-            {
-                NoYieldLockGuard g;
-                nRet = reinterpret_cast<LRESULT>(
-                    GetDCEx(reinterpret_cast<HWND>(wParam), nullptr, 0x00000002L));
-            }
-            break;
         case (SAL_MSG_RELEASEDC):
             {
                 NoYieldLockGuard g;
diff --git a/vcl/win/window/salframe.cxx b/vcl/win/window/salframe.cxx
index 2cf8a4020736..7fd12ef926d7 100644
--- a/vcl/win/window/salframe.cxx
+++ b/vcl/win/window/salframe.cxx
@@ -862,7 +862,6 @@ WinSalFrame::WinSalFrame()
     mhCursor            = LoadCursor( nullptr, IDC_ARROW );
     mhDefIMEContext     = nullptr;
     mpLocalGraphics     = nullptr;
-    mpThreadGraphics    = nullptr;
     m_eState = vcl::WindowState::Normal;
     mnShowState         = SW_SHOWNORMAL;
     mnMinWidth          = 0;
@@ -948,8 +947,6 @@ bool WinSalFrame::ReleaseFrameGraphicsDC( WinSalGraphics* pGraphics )
     pGraphics->setHDC(nullptr);
     SendMessageW( pSalData->mpInstance->mhComWnd, SAL_MSG_RELEASEDC,
         reinterpret_cast<WPARAM>(mhWnd), reinterpret_cast<LPARAM>(hDC) );
-    if ( pGraphics == mpThreadGraphics )
-        pSalData->mnCacheDCInUse--;
     return true;
 }
 
@@ -967,14 +964,6 @@ WinSalFrame::~WinSalFrame()
         *ppFrame = mpNextFrame;
     mpNextFrame = nullptr;
 
-    // destroy the thread SalGraphics
-    if ( mpThreadGraphics )
-    {
-        ReleaseFrameGraphicsDC( mpThreadGraphics );
-        delete mpThreadGraphics;
-        mpThreadGraphics = nullptr;
-    }
-
     // destroy the local SalGraphics
     if ( mpLocalGraphics )
     {
@@ -1010,7 +999,6 @@ WinSalFrame::~WinSalFrame()
 
 bool WinSalFrame::InitFrameGraphicsDC( WinSalGraphics *pGraphics, HDC hDC, HWND hWnd )
 {
-    SalData* pSalData = GetSalData();
     assert( pGraphics );
     pGraphics->setHWND( hWnd );
 
@@ -1023,8 +1011,6 @@ bool WinSalFrame::InitFrameGraphicsDC( WinSalGraphics *pGraphics, HDC hDC, HWND
     if ( !hDC )
         return false;
 
-    if ( pGraphics == mpThreadGraphics )
-        pSalData->mnCacheDCInUse++;
     return true;
 }
 
@@ -1037,41 +1023,20 @@ SalGraphics* WinSalFrame::AcquireGraphics()
     WinSalGraphics *pGraphics = nullptr;
     HDC hDC = nullptr;
 
-    // Other threads get an own DC, because Windows modify in the
-    // other case our DC (changing clip region), when they send a
-    // WM_ERASEBACKGROUND message
-    if ( !pSalData->mpInstance->IsMainThread() )
-    {
-        // We use only three CacheDC's for all threads, because W9x is limited
-        // to max. 5 Cache DC's per thread
-        if ( pSalData->mnCacheDCInUse >= 3 )
-            return nullptr;
-
-        if ( !mpThreadGraphics )
-            mpThreadGraphics = new WinSalGraphics(WinSalGraphics::WINDOW, true, mhWnd, this);
-        pGraphics = mpThreadGraphics;
-        assert( !pGraphics->getHDC() );
-        hDC = reinterpret_cast<HDC>(static_cast<sal_IntPtr>(SendMessageW( pSalData->mpInstance->mhComWnd,
-                                    SAL_MSG_GETCACHEDDC, reinterpret_cast<WPARAM>(mhWnd), 0 )));
-    }
-    else
-    {
-        if ( !mpLocalGraphics )
-            mpLocalGraphics = new WinSalGraphics(WinSalGraphics::WINDOW, true, mhWnd, this);
-        pGraphics = mpLocalGraphics;
-        hDC = pGraphics->getHDC();
-        if ( !hDC )
-            hDC = GetDC( mhWnd );
-    }
+    assert(pSalData->mpInstance->IsMainThread());
+    if ( !mpLocalGraphics )
+        mpLocalGraphics = new WinSalGraphics(WinSalGraphics::WINDOW, true, mhWnd, this);
+    pGraphics = mpLocalGraphics;
+    hDC = pGraphics->getHDC();
+    if ( !hDC )
+        hDC = GetDC( mhWnd );
 
     mbGraphics = InitFrameGraphicsDC( pGraphics, hDC, mhWnd );
     return mbGraphics ? pGraphics : nullptr;
 }
 
-void WinSalFrame::ReleaseGraphics( SalGraphics* pGraphics )
+void WinSalFrame::ReleaseGraphics( SalGraphics* /*pGraphics*/ )
 {
-    if ( mpThreadGraphics == pGraphics )
-        ReleaseFrameGraphicsDC( mpThreadGraphics );
     mbGraphics = false;
 }
 
@@ -1497,29 +1462,7 @@ void WinSalFrame::ImplSetParentFrame( HWND hNewParentWnd, bool bAsChild )
     }
 
     // to recreate the DCs, if they were destroyed
-    bool bHadLocalGraphics = false, bHadThreadGraphics = false;
-
-    HFONT   hFont   = nullptr;
-    HPEN    hPen    = nullptr;
-    HBRUSH  hBrush  = nullptr;
-
-    int oldCount = pSalData->mnCacheDCInUse;
-
-    // release the thread DC
-    if ( mpThreadGraphics )
-    {
-        // save current gdi objects before hdc is gone
-        HDC hDC = mpThreadGraphics->getHDC();
-        if ( hDC )
-        {
-            hFont  = static_cast<HFONT>(GetCurrentObject( hDC, OBJ_FONT ));
-            hPen   = static_cast<HPEN>(GetCurrentObject( hDC, OBJ_PEN ));
-            hBrush = static_cast<HBRUSH>(GetCurrentObject( hDC, OBJ_BRUSH ));
-        }
-
-        bHadThreadGraphics = ReleaseFrameGraphicsDC( mpThreadGraphics );
-        assert( (bHadThreadGraphics && hDC) || (!bHadThreadGraphics && !hDC) );
-    }
+    bool bHadLocalGraphics = false;
 
     // release the local DC
     if ( mpLocalGraphics )
@@ -1535,27 +1478,6 @@ void WinSalFrame::ImplSetParentFrame( HWND hNewParentWnd, bool bAsChild )
     // succeeded ?
     SAL_WARN_IF( !IsWindow( hWnd ), "vcl", "WinSalFrame::SetParent not successful");
 
-    // re-create thread DC
-    if( bHadThreadGraphics )
-    {
-        HDC hDC = reinterpret_cast<HDC>(static_cast<sal_IntPtr>(
-                    SendMessageW( pSalData->mpInstance->mhComWnd,
-                        SAL_MSG_GETCACHEDDC, reinterpret_cast<WPARAM>(hWnd), 0 )));
-        InitFrameGraphicsDC( mpThreadGraphics, hDC, hWnd );
-        if ( hDC )
-        {
-            // re-select saved gdi objects
-            if( hFont )
-                SelectObject( hDC, hFont );
-            if( hPen )
-                SelectObject( hDC, hPen );
-            if( hBrush )
-                SelectObject( hDC, hBrush );
-
-            SAL_WARN_IF( oldCount != pSalData->mnCacheDCInUse, "vcl", "WinSalFrame::SetParent() hDC count corrupted");
-        }
-    }
-
     // re-create local DC
     if( bHadLocalGraphics )
         InitFrameGraphicsDC( mpLocalGraphics, GetDC( hWnd ), hWnd );
@@ -2189,8 +2111,6 @@ void WinSalFrame::Flush()
 {
     if(mpLocalGraphics)
         mpLocalGraphics->Flush();
-    if(mpThreadGraphics)
-        mpThreadGraphics->Flush();
     GdiFlush();
 }