sw, createTextRangeByPixelPosition(): fix crash when the position is an image

Using createTextRangeByPixelPosition() with a pixel position that leads
to a graphic node resulted in a crash.

The direct reason for this is that the makeMark() call in
SwXTextRange::SetPositions() returns nullptr in case rPaM points to a
graphic node, but later we dereference that result unconditionally. This
also uncovers that the XTextRange returned by
createTextRangeByPixelPosition() is meant to point to a text node, but a
pixel position may be closest to a graphic node.

Fix the problem by explicitly checking for graphic nodes; and try to
look up the anchor position of such graphics, which will be definitely a
text node.

In practice this will mean that in case the image's anchor type is
as-char, then we'll return a cursor position which will be on the left
hand side of the image.

Change-Id: Ief58148247fe3cd4371ed245b4eff5b45ca2aa15
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/143092
Reviewed-by: Miklos Vajna <vmiklos@collabora.com>
Tested-by: Jenkins

1 files changed, 6 insertions, 1 deletions

diff --git a/offapi/com/sun/star/text/XTextViewTextRangeSupplier.idl b/offapi/com/sun/star/text/XTextViewTextRangeSupplier.idl
index 56ea30efc070..faa85578c458 100644
--- a/offapi/com/sun/star/text/XTextViewTextRangeSupplier.idl
+++ b/offapi/com/sun/star/text/XTextViewTextRangeSupplier.idl
@@ -25,7 +25,12 @@ module com {  module sun {  module star {  module text {
  */
 interface XTextViewTextRangeSupplier: com::sun::star::uno::XInterface
 {
-    /** @returns
+    /** creates the text range of the document model position at a view-dependent pixel position.
+
+        Note that in case the model position is a graphic, then the model position of its anchor is
+        returned.
+
+        @returns
                 the text range of the document position.
      */
     com::sun::star::text::XTextRange createTextRangeByPixelPosition([in] com::sun::star::awt::Point PixelPosition);