[asterisk-dev] zero is a legitimate value for SIP CSeq numbers, right ?

[Luigi Rizzo]

On Thu, Oct 12, 2006 at 12:37:03PM -0500, Kevin P. Fleming wrote:
> ----- Luigi Rizzo <rizzo at icir.org> wrote:
...
> >     Other than using an external flag, i think a better
> >     choice for "not initialized" is 0xffffffff, which is not
> >     a valid initial CSeq for a dialogue.
> 
> It's not a valid value for CSeq, period, not just as an initial value. Any value equal to or greater than 2**31 (0x80000000) is an invalid value. In this case I would agree that making this change is logical.

well there are numerous discussions in various mailing lists,
all agreeing that the CSeq within a dialog can grow >= 2^31 and
up to 2^32-1.
That's the reason for requiring it to be represented as uint32,
hoping that there is never a practical need to check for overflows.

cheers
luigi