[lwip-members] lightweight protection

[Jani Monoses]

Hi
in pbuf.c SYS_ARCH_PROTECT & co are called unconditionnally while in memp.c
they are called only if SYS_LIGHTWEIGHT_PROT is 1.Any reason for this 
inconsistency?
In pbuf they seem to be an addition to semaphore locking while in memp an 
alternative.

Another question: I only see the unix arch defining these at the moment so I'm 
not sure
how they were intended to be used.Specifically  is sys_arch_decl_protect 
supposed to
declare a lock variable?In that case from the use of macros in pbuf that 
variable seems
to be local and thus does not protect from accesses from another function to 
the protected data.
Or if the lock is supposed to be global than maybe a DECL or two at the 
beginning of the file
and various protect/unprotect macro pairs in the functions would be a better 
layout.

Jani.