Fix a hairy optimizer bug that causes the expression:
'ip and ((icmp and dst host 1.1.1.1 and not host 2.2.2.2) or (host 1.1.1.1 and src host 3.3.3.3))'
to compile incorrectly. Details about to be mailed to LBL.
counting any extra jumps required by a flowgraph node (the conditional
jump instructions have an 8-bit offset; if the target is more than 256
instructions away, we generate a nearby "jump always" to the target, and
jump to that instead).
filter, always attach a copy, as "pcap-linux.c" does; that way, after a
program uses "pcap_setfilter()", it can safely use "pcap_freecode()" to
free up the BPF instructions allocated by "pcap_compile()". Also,
always free it up when the "pcap_t" is closed.
Get rid of the "pcap_t *" argument to "pcap_freecode()", as it's not
necessary.
Document "pcap_freecode()", for the benefit of programs that might
repeatedly compile filter programs and attach them, so that they can
free them up after attaching them and avoid leaking memory for them.
./configure --enable-ipv6 (requires getaddrinfo(3) and getnameinfo(3)).
TODO: make it work even without getaddrinfo(3) or getnameinfo(3)
(or, tcpdump/configure.in should provide alternative version by
AC_REPLACE_FUNCS)
TODO: make IPv6 filtering code work by default
TODO: make "protochain" friendly with optimization
guy