[vdr] Re: DVD playback pumps 100's of error msgs

[Andreas Schultz <aschultz@cs.uni-magdeburg.de>]

Hi Richard,

patch included.

Richard Cieply wrote:
> Hi list,
> 
> the following problem occurs when replaying a DVD with
> vdr-1.0.0-pre2 with AIO-20020227, dvb-0.94:
> the msg log is pumped with hundreds of messages saying:
> "vdr[10373]: ERROR: can't allocate frame buffer (count=1040)"
> This message occurs many times per second (~115/sec).
> 
> However this message is misleading.
> It is thrown by the method
> cFrame::cFrame(const uchar *Data, int Count, eFrameType Type, int Index)
> in ringbuffer.c.
> In this code snipplet:
> if (data && Data)
>    memcpy(data, Data, count);
> else
>    esyslog(LOG_ERR, "ERROR: can't allocate frame buffer (count=%d)", 
> count);

Auahhh, that hurts. I introduced that at least a week ago and didn't 
notice my syslog beeing swamped with those messages.

> I crosschecked it and saw that not the allocation of 'data' is the 
> problem but that 'Data' contains a null pointer.
> Therefor the else case is being triggered.
> 
> I didn't check if it is OK to pass a null pointer here, but as 'Count' 
> is 1040 (in this case) it seems to me that 'Data' shouldn't be NULL.
> Or the other way round:
> If it is OK to pass NULL then the cFrame constructor should behave 
> different than it is right now.

The way i want it, passing NULL is ok.

> By the way:
> this problem occured with arbitrary DVDs here so it should be no problem 
> to reproduce it.
> My last version was vdr-0.99 with AIO20020213.
> In this version the problem does not accur.
> 
> best regards
>   Richard

Have fun

     Andreas

===== ringbuffer.c 1.2 vs edited =====
--- 1.2/ringbuffer.c    Thu Feb 23 20:37:07 2012
+++ edited/ringbuffer.c Thu Feb 28 13:43:21 2002
@@ -221,9 +221,10 @@
    type = Type;
    index = Index;
    data = new uchar[count];
-  if (data && Data)
-     memcpy(data, Data, count);
-  else
+  if (data) {
+     if (Data)
+        memcpy(data, Data, count);
+  } else
       esyslog(LOG_ERR, "ERROR: can't allocate frame buffer (count=%d)", 
count);
    next = NULL;
  }