[vlc-devel] stream_Peek memory management...

[Laurent Aimar]

On Mon, Sep 19, 2011 at 05:32:43PM -0700, Peter Tap wrote:
> Laurent,
> 
> Thank you for your help. Things now make more sense.
> 
> I had written a stream filter for decoding an encrypted media file. Currently,
> the encryption is a simple XOR mechanism. In my "Peek" implementation, I was
> simply calling the underlying stream_Peek method and XORing the read buffer
> before returning. The problem I am running into is that the underlying stream
> may used cached data (src/input/stream.c). As a result, I end up XORing data
> that is already XORed.
 The data pointer returned by stream_Peek() is const uint8_t* and as such
you must not modify the pointed data.
> 
> Looks like the only way to get around this problem is to add my own layer of
> cached data.
 If you modify, the data, then yes you need to do it in your own buffer.

Regards,

-- 
fenrir