sfx2: nullptr pViewShell was seen in SfxLokHelper::getView()

I'm not sure how to trigger this reliably, but Pranav got this:

	#0  0x00007fb2f471bbf0 in SfxLokHelper::getView(SfxViewShell*) (pViewShell=0x0) at sfx2/source/view/lokhelper.cxx:82
	#1  0x00007fb2f75edf4f in doc_paintPartTile(LibreOfficeKitDocument*, unsigned char*, int, int, int, int, int, int, int) (pThis=0x7fb290253c40, pBuffer=0x281fbd0 "", nPart=0, nCanvasWidth=1024, nCanvasHeight=256, nTilePosX=0, nTilePosY=11520, nTileWidth=15360, nTileHeight=3840) at desktop/source/lib/init.cxx:1338

Given that SfxViewShell::Current() may indeed return nullptr (e.g.
during shutdown), change SfxLokHelper::getView() to return -1 in that
case, and adapt client code to handle that.

Change-Id: Ia191c843c8a993f3d7157de432af57964c0a8f63
Reviewed-on: https://gerrit.libreoffice.org/28583
Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>
Tested-by: Jenkins <ci@libreoffice.org>

1 files changed, 15 insertions, 4 deletions

diff --git a/desktop/source/lib/init.cxx b/desktop/source/lib/init.cxx
index f4f46221f7b0..5f7ac7a6a384 100644
--- a/desktop/source/lib/init.cxx
+++ b/desktop/source/lib/init.cxx
@@ -1365,7 +1365,10 @@ static void doc_paintPartTile(LibreOfficeKitDocument* pThis,
 
     // Disable callbacks while we are painting.
     LibLODocument_Impl* pDocument = static_cast<LibLODocument_Impl*>(pThis);
-    std::size_t nView = SfxLokHelper::getView();
+    int nView = SfxLokHelper::getView();
+    if (nView < 0)
+        return;
+
     pDocument->mpCallbackFlushHandlers[nView]->setPartTilePainting(true);
     try
     {
@@ -1438,7 +1441,10 @@ static void doc_registerCallback(LibreOfficeKitDocument* pThis,
     SolarMutexGuard aGuard;
     LibLODocument_Impl* pDocument = static_cast<LibLODocument_Impl*>(pThis);
 
-    std::size_t nView = SfxLokHelper::getView();
+    int nView = SfxLokHelper::getView();
+    if (nView < 0)
+        return;
+
     pDocument->mpCallbackFlushHandlers[nView].reset(new CallbackFlushHandler(pThis, pCallback, pData));
 
     if (SfxViewShell* pViewShell = SfxViewFrame::Current()->GetViewShell())
@@ -1507,7 +1513,9 @@ static void doc_postUnoCommand(LibreOfficeKitDocument* pThis, const char* pComma
     LibLODocument_Impl* pDocument = static_cast<LibLODocument_Impl*>(pThis);
 
     std::vector<beans::PropertyValue> aPropertyValuesVector(jsonToPropertyValuesVector(pArguments));
-    std::size_t nView = SfxLokHelper::getView();
+    int nView = SfxLokHelper::getView();
+    if (nView < 0)
+        return;
 
     // handle potential interaction
     if (gImpl && aCommand == ".uno:Save")
@@ -1593,7 +1601,10 @@ static void doc_postMouseEvent(LibreOfficeKitDocument* pThis, int nType, int nX,
     }
 
     LibLODocument_Impl* pLib = static_cast<LibLODocument_Impl*>(pThis);
-    std::size_t nView = SfxLokHelper::getView();
+    int nView = SfxLokHelper::getView();
+    if (nView < 0)
+        return;
+
     if (pLib->mpCallbackFlushHandlers[nView])
     {
         pLib->mpCallbackFlushHandlers[nView]->queue(LOK_CALLBACK_MOUSE_POINTER, aPointerString.getStr());