ref: a00b6bdbfa72a1688a866edf5f825720c9874ada
dir: /sys/src/cmd/ip/snoopy/aoemd.c/
#include <u.h> #include <libc.h> #include <ip.h> #include "dat.h" #include "protos.h" typedef struct { uchar res; uchar cmd; uchar ea[6]; } Hdr; enum { Ocmd, Oea, Hsize = 8, }; static Field p_fields[] = { {"cmd", Fnum, Ocmd, "command", }, {"ea", Fnum, Oea, "ethernet addr", }, nil }; static void p_compile(Filter *f) { if(f->op == '='){ compile_cmp(aoemd.name, f, p_fields); return; } sysfatal("unknown aoemd field: %s", f->s); } static int p_filter(Filter *f, Msg *m) { uchar buf[6]; int i; Hdr *h; if(m->pe - m->ps < Hsize) return 0; h = (Hdr*)m->ps; m->ps += Hsize; switch(f->subop){ case Ocmd: return h->cmd == f->ulv; case Oea: for(i = 0; i < 6; i++) buf[i] = f->ulv >> ((5 - i)*8); return memcmp(buf, h->ea, 6) == 0; } return 0; } static char *ctab[] = { " ", " +", " -", }; static int p_seprint(Msg *m) { char *s; Hdr *h; if(m->pe - m->ps < Hsize) return 0; h = (Hdr*)m->ps; m->ps += Hsize; /* no next protocol */ m->pr = nil; s = "unk"; if(h->cmd < nelem(ctab)) s = ctab[h->cmd]; m->p = seprint(m->p, m->e, "cmd=%d%s ea=%E\n", h->cmd, s, h->ea); return 0; } Proto aoemd = { "aoemd", p_compile, p_filter, p_seprint, nil, nil, p_fields, defaultframer, };