Hi On Fri, Feb 17, 2006 at 12:36:31PM -0500, Rich Felker wrote:
On Fri, Feb 17, 2006 at 07:05:48PM +0200, Oded Shimon wrote:
If the header is enclosed in the checksum, it's natural to consider it part of the syncpoint packet anyway. Also there's no reason a checksum needs to come from just one buffer. As long as you pass a state pointer to your checksum function you can checksum arbitrarily many different buffers as if they were all connected..
Yes, I know, this is why I said I'm not against forward_ptr being in checksum, but I am against forward_ptr being in syncpoints!
The point of forward_ptr being in syncpoints is to be able to add fields to syncpoints, not to frame headers, cause we already have that, right? The structure is:
<startcode> <forward_ptr> <syncpoint> <reserved> <frame header> <checksum>
(reserved being reserved bytes for syncpoint) Now, where the hell does the forward_ptr point to? If it points to after the checksum like all other headers, you won't know where the hell to start parsing the frame header. Pointing to right before the frame header is weird, because the checksum comes later. Putting the reserved bytes of the _syncpoint_ after the frame header is even weirder (data of syncpoint cut in two pieces??)
OK, I agree. Michael, do you have comments?
none which will help the clean way to do this is 2 checksums 1 for the syncpoint, 1 for the frame header, and ptr points to the first checksum/frame header so i agree that no forward ptr in syncpoints is ok, unless we come up with a clean&low overhead solution [...] -- Michael