RE: [XaraXtreme-dev] Segmentation fault with multiple blending

["Neil Howe" <NeilH@xxxxxxxx>]

Thanks for reporting this crash Domagoj. And perhaps you've given us the
fix for it too - well found.

Neil

> -----Original Message-----
> From: owner-dev@xxxxxxxxxxxxxxxx [mailto:owner-dev@xxxxxxxxxxxxxxxx]
On
> Behalf Of Domagoj Pensa
> Sent: 11 April 2006 19:20
> To: dev@xxxxxxxxxxxxxx
> Subject: [XaraXtreme-dev] Segmentation fault with multiple blending
> 
> Hi!
> 
> When I tried to blend 3 objects together (from object 1 to object 2
and
> then from object 2 to object 3) Xara (rev 804) crashed with
> "Segmentation fault".
> 
> The problem occurs in OpBlendNodes::DoBlendBlendAndObject() (in
> tools/blndtool.cpp). It seems that when we try to blend from already
> blended group that pNodeBlendStart is NULL. This is what I got from
gdb:
> 
> Program received signal SIGSEGV, Segmentation fault.
> [Switching to Thread -1208932688 (LWP 2267)]
> OpBlendNodes::GetNodeClosestToPoint (this=0xa00efb8, ppInk=0xbfc7c4c8,
> StartBlend=1) at .././Kernel/node.h:1143
> 1143            return(Child);
> 
> Also, I've noticed that there are 2 lines commented which assign value
> to pNodeBlendStart. When I recompiled with those two lines everything
> worked.
> 
> This is from "svn diff":
> 
> Index: tools/blndtool.cpp
> ===================================================================
> --- tools/blndtool.cpp  (revision 804)
> +++ tools/blndtool.cpp  (working copy)
> @@ -3688,8 +3688,8 @@
>          BOOL ok = FALSE;
>          if (BlendIsStart)
>          {
> -//             BlenderInfoItem* pItem =
> (BlenderInfoItem*)BlenderList.GetTail();
> -//             pNodeBlendStart = pNodeBlend;
> +               BlenderInfoItem* pItem =
> (BlenderInfoItem*)BlenderList.GetTail();
> +               pNodeBlendStart = pNodeBlend;
>                  ok              = GetNodeClosestToPoint(&pNodeStart,
> TRUE);
>                  pNodeEnd                = pRefEnd->pNode;
>                  pContextNode    = pNodeEnd;
> 
> I'm sure there is a reason why above two lines are commented, but when
> they are included at least it doesn't crash and multiple blending
works.
>   Anyway, I know that you guys would fix this properly. :)
> 
> Keep up the good work!
> 
> Regards,
> Domagoj