Re: [xine-devel] PATCH: fix possible FPE in demux_asf

[Vedran Rodic <vedran@xxxxxxxxxx>]

Diego 'Flameeyes' Pettenò wrote:

> On Tuesday 28 February 2006 12:58, Vedran Rodic wrote:
>  
>
> > This patch fixes it and is pretty self explanatory.
> >    
> I'd rather put it as "this->length >= 1000"; divisions are usually less 
> performant that comparative tests.
>
> Or it could just change the division (without changing the if clause) to
>
> this->rate = (file_size*1000) / this->length;
>
> so that the number of operations remain constant.
>  

You're right. The last option seems ok.



Index: src/demuxers/demux_asf.c
===================================================================
RCS file: /cvsroot/xine/xine-lib/src/demuxers/demux_asf.c,v
retrieving revision 1.173
diff -u -r1.173 demux_asf.c
--- src/demuxers/demux_asf.c    14 Nov 2005 12:34:46 -0000      1.173
+++ src/demuxers/demux_asf.c    28 Feb 2006 13:05:48 -0000
@@ -434,7 +434,7 @@
 
           if (this->length) {
             /* FIXME: the rate is not constant ! */
-            this->rate = file_size / (this->length / 1000);
+            this->rate = (file_size * 1000) / this->length;
           } else {
             this->rate = 0;
           }