I think this is checking that the amount of data *already* received is larger than maxinput, and if so, then rejecting. The idea is to not read that much data in the first place.
Yes, by the last buffer size only, it may not read the whole buffer, so cheking befor for requested size is not accurate yet, i may ask for 4096 bytes but read only 100 for whatever reasons.
I didn't look carefully so it may only be overshooting by the receive buffer size or some such, but the same principle applies to the following check for max headers. Here the headers have been completely parsed into an Ns_Set structure, and *then* the size is checked. Too late... :-(
It does it after each line only, whatever amount was read is in the buffer already, so we parse it line by line and i check after each line.
