[lwip-users] Stray pointer in dhcp.c?

[Dan Lewis]

Has anyone else experienced problems that behave as if there's a stray pointer 
in dhcp.c? I haven't been able to track it down, but here's what's happening to 
me:

I have a embedded web server running on a small 386EX-based board sold by JK 
Microsystems. Their board comes with a ROM-based version of MS/DOS. My server, 
however, switches from real to protected mode at the beginning, and then 
occassionally switches temporarily back to real mode when needed to access the 
MS/DOS file system API. When the server terminates, it returns to real mode and 
then to MS/DOS. The details of how this is done are ugly, but work - it 
involves switching interrupt vector tables and reprogramming the 8253 timer and 
8259 PIC as well.

The issue is this: If I assign the IP address, gateway, and netmask statically, 
everything works great. But if I let the DHCP client assign them automatically, 
everything works great until I terminate the server - at which point it hangs 
rather than returning successfully to MS/DOS.

I've narrowed it down to the point where the symptoms are absolutely related to 
DHCP. Enable it and it fails; disable it and it works. But so far this is as 
far as I've gotten. I'll keep poking, but just wondered if anyone else has seen 
anything like this before.

By the way, I'm using version version 1.9 of dhcp.c from CVS.

All the best,

Dan Lewis, Chair
Computer Engineering
Santa Clara University