reading packets from a pcap_t, and make "pcap_read()" call it. That
removes the last place where we have to check for a pcap_t that refers
to a DAG card rather than a live capture, so get rid of the "is_dag" flag.
handles setting a filter for a pcap_t. Have "pcap_setfilter()" call it,
rather than being a per-platform function. The per-platform functions
don't need to check for an offline capture any more, as they're not
called for an offline capture (and the ones that just call
"install_bpf_program()" don't need to exist at all).
getting statistics for a pcap_t. Have "pcap_stats()" call it, rather
than being a per-platform function; have stats routines for non-live
pcap_t's that return an error.
argument to "pcap_open_live()" a "const" pointer.
Constify some additional device name arguments, and update the man page
to reflect some arguments that were already consts.
Young <dyoung@ojctech.com>, with some minor changes by Jason R. Thorpe
<thorpej@netbsd.org>, and further changes by me to support it on BPF
systems lacking BIOCGDLTLIST and other platforms lacking an equivalent
feature.
Update Jason Thorpe's e-mail address (Zembu is going away, if it hasn't
done so already).
Add APIs to map DLT names to DLT values and vice versa.
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.