[MPlayer-dev-eng] [PATCH] Wrong typecast in loader/dshow/output.c

[Vladimir Voroshilov]

COutputMemPin_Queryinterface belongs to COutputMemPin, but casts This
parameter as COutputPin. This does not affect until DirectShow call
QueryInterface to retrive IMemInputPin from COutputMemPin. For
example:

Example1:
pPin->vt->QueryInterface(pPin,&IID_IMemInputPin,&pMemPin1); // FINE
pPin->vt->QueryInterface(pPin,&IID_IMemInputPin,&pMemPin2); // FINE

Example2:
pPin->vt->QueryInterface(pPin,&IID_IMemInputPin,&pMemPin1); // FINE
pMemPin1->vt->QueryInterface(pMemPin1,&IID_IMemInputPin,&pMemPin2);
//Should crash

Seem like DirectShow binary codecs usually does not query IMemInputPin
interface from IMemInputPin and thus all works fine.

Attached patch fixes this bug.
I have tested it under Linux with divxds dshow codec and all works fine.

Opinions?

-- 
Regards,
Vladimir Voroshilov     mailto:voroshil at gmail.com
JID: voroshil at jabber.ru
ICQ: 95587719
-------------- next part --------------
Index: outputpin.c
===================================================================
--- outputpin.c	(revision 22035)
+++ outputpin.c	(working copy)
@@ -587,7 +587,7 @@
  */
 static HRESULT STDCALL COutputMemPin_QueryInterface(IUnknown* This, const GUID* iid, void** ppv)
 {
-    COutputPin* p = (COutputPin*)This;
+    COutputMemPin* p = (COutputMemPin*)This;
 
     Debug printf("COutputMemPin_QueryInterface(%p) called\n", This);
     if (!ppv)
@@ -608,8 +608,8 @@
     }*/
     if(!memcmp(iid, &IID_IMemInputPin, 16))
     {
-	*ppv = p->mempin;
-	p->mempin->vt->AddRef(This);
+	*ppv = p;
+	p->vt->AddRef(This);
 	return 0;
     }
     Debug printf("Unknown interface : %08x-%04x-%04x-%02x%02x-" \