Re: [lwip-devel] ARP Table limited to 127 (s8_t)?

[address@hidden]

Fabian Koch wrote:
> I was wondering if there is a reason for ARP_TABLE_SIZE to be limited to s8_t 
> instead of u8_t?

A quick look shows that the s8_t value is used to return both the index 
(>= 0) or an err_t (<0). Of course that doesn't work with an u8_t. Since 
only ERR_MEM is returned, that can of course be solved differently (e.g. 
255 means invalid entry - where ERR_MEM is used now).

We could also make the index type configurable to support even more 
entries. However, the search is kind of slow since it is a linear search 
done for every ARP packet (or even for every TX packet if NETIF_ADDRHINT 
is not used).

Simon