sys/src/cmd/ip/snoopy/cec.c

   1 #include <u.h>
   2 #include <libc.h>
   3 #include <ip.h>
   4 #include "dat.h"
   5 #include "protos.h"
   6
   7 typedef struct{
   8         uchar   type;
   9         uchar   conn;
  10         uchar   seq;
  11         uchar   len;
  12 }Hdr;
  13
  14 enum{
  15         Hsize   = 4,
  16 };
  17
  18 enum{
  19         Otype,
  20         Oconn,
  21         Oseq,
  22         Olen,
  23 };
  24
  25 static Field p_fields[] =
  26 {
  27         {"type",        Fnum,   Otype,          "type", },
  28         {"conn",        Fnum,   Oconn,          "conn", },
  29         {"seq",         Fnum,   Oseq,           "seq",  },
  30         {"len",         Fnum,   Olen,           "len",  },
  31         {0}
  32 };
  33
  34 static void
  35 p_compile(Filter *f)
  36 {
  37         if(f->op == '='){
  38                 compile_cmp(aoe.name, f, p_fields);
  39                 return;
  40         }
  41         sysfatal("unknown aoe field: %s", f->s);
  42 }
  43
  44 static int
  45 p_filter(Filter *f, Msg *m)
  46 {
  47         Hdr *h;
  48
  49         if(m->pe - m->ps < Hsize)
  50                 return 0;
  51
  52         h = (Hdr*)m->ps;
  53         m->ps += Hsize;
  54
  55         switch(f->subop){
  56         case Otype:
  57                 return h->type == f->ulv;
  58         case Oconn:
  59                 return h->conn = f->ulv;
  60         case Oseq:
  61                 return h->seq = f->ulv;
  62         case Olen:
  63                 return h->len = f->ulv;
  64         }
  65         return 0;
  66 }
  67
  68 static char* ttab[] = {
  69         "Tinita",
  70         "Tinitb",
  71         "Tinitc",
  72         "Tdata",
  73         "Tack",
  74         "Tdiscover",
  75         "Toffer",
  76         "Treset",
  77 };
  78
  79 static int
  80 p_seprint(Msg *m)
  81 {
  82         char *s, *p, buf[4];
  83         Hdr *h;
  84
  85         if(m->pe - m->ps < Hsize)
  86                 return 0;
  87
  88         h = (Hdr*)m->ps;
  89         m->ps += Hsize;
  90
  91         m->pr = nil;
  92
  93         if(h->type < nelem(ttab))
  94                 s = ttab[h->type];
  95         else{
  96                 snprint(buf, sizeof buf, "%d", h->type);
  97                 s = buf;
  98         }
  99
 100         p = (char*)m->ps;
 101         m->p = seprint(m->p, m->e, "type=%s conn=%d seq=%d len=%d %.*s",
 102                 s, h->conn, h->seq, h->len,
 103                 (int)utfnlen(p, h->len), p);
 104         return 0;
 105 }
 106
 107 Proto cec =
 108 {
 109         "cec",
 110         p_compile,
 111         p_filter,
 112         p_seprint,
 113         nil,
 114         nil,
 115         p_fields,
 116         defaultframer,
 117 };