bool Clausula::subsume(const Clausula& otra) const
{
Sustitucion s;
if (!predicados().subconjunto(otra.predicados()))
return false;
return subsume(s, literales.begin(), otra);
}
bool Clausula::subsume(Sustitucion& s, const_iterator lit1, const Clausula& otra) const
{
if (lit1 == literales.end())
return true;
bool subsum = false;
const_iterator it_otra = otra.begin();
while (it_otra != otra.end() && !subsum) {
Sustitucion s1 = s;
if (lit1->unificarSubsuncion(*it_otra, s1)) {
const_iterator sig = lit1;
++sig;
subsum = subsume(s, sig, otra);
}
++it_otra;
}
return subsum;
}
static void
reply(int fd, uchar *buf, DNSmsg *rep, Request *reqp)
{
int len;
char tname[32];
if(debug || (trace && subsume(trace, rep->qd->owner->name)))
dnslog("%d: reply (%I/%d) %d %s %s qd %R an %R ns %R ar %R",
reqp->id, buf, buf[4]<<8 | buf[5],
rep->id, rep->qd->owner->name,
rrname(rep->qd->type, tname, sizeof tname),
rep->qd, rep->an, rep->ns, rep->ar);
len = convDNS2M(rep, &buf[Udphdrsize], Maxudp);
len += Udphdrsize;
if(write(fd, buf, len) != len)
dnslog("error sending reply: %r");
}
bool Clausula::subsume(const Clausula& otra) const
{
Sustitucion s;
return subsume(s, literales.begin(), otra);
}
/*
* a process to act as a dns server for outside reqeusts
*/
void
dnudpserver(char *mntpt)
{
volatile int fd, len, op, rcode;
char *volatile err;
volatile char tname[32];
volatile uchar buf[Udphdrsize + Maxudp + 1024];
volatile DNSmsg reqmsg, repmsg;
Inprogress *volatile p;
volatile Request req;
Udphdr *volatile uh;
/*
* fork sharing text, data, and bss with parent.
* stay in the same note group.
*/
switch(rfork(RFPROC|RFMEM|RFNOWAIT)){
case -1:
break;
case 0:
break;
default:
return;
}
fd = -1;
restart:
procsetname("udp server announcing");
if(fd >= 0)
close(fd);
while((fd = udpannounce(mntpt)) < 0)
sleep(5000);
// procsetname("udp server");
memset(&req, 0, sizeof req);
if(setjmp(req.mret))
putactivity(0);
req.isslave = 0;
req.id = 0;
req.aborttime = 0;
/* loop on requests */
for(;; putactivity(0)){
procsetname("served %d udp; %d alarms",
stats.qrecvdudp, stats.alarms);
memset(&repmsg, 0, sizeof repmsg);
memset(&reqmsg, 0, sizeof reqmsg);
alarm(60*1000);
len = read(fd, buf, sizeof buf);
alarm(0);
if(len <= Udphdrsize)
goto restart;
redistrib(buf, len);
uh = (Udphdr*)buf;
len -= Udphdrsize;
// dnslog("read received UDP from %I to %I",
// ((Udphdr*)buf)->raddr, ((Udphdr*)buf)->laddr);
getactivity(&req, 0);
req.aborttime = timems() + Maxreqtm;
// req.from = smprint("%I", ((Udphdr*)buf)->raddr);
req.from = smprint("%I", buf);
rcode = 0;
stats.qrecvdudp++;
err = convM2DNS(&buf[Udphdrsize], len, &reqmsg, &rcode);
if(err){
/* first bytes in buf are source IP addr */
dnslog("server: input error: %s from %I", err, buf);
free(err);
goto freereq;
}
if (rcode == 0)
if(reqmsg.qdcount < 1){
dnslog("server: no questions from %I", buf);
goto freereq;
} else if(reqmsg.flags & Fresp){
dnslog("server: reply not request from %I", buf);
goto freereq;
}
op = reqmsg.flags & Omask;
if(op != Oquery && op != Onotify){
dnslog("server: op %d from %I", reqmsg.flags & Omask,
buf);
goto freereq;
}
if(debug || (trace && subsume(trace, reqmsg.qd->owner->name)))
dnslog("%d: serve (%I/%d) %d %s %s",
req.id, buf, uh->rport[0]<<8 | uh->rport[1],
reqmsg.id, reqmsg.qd->owner->name,
rrname(reqmsg.qd->type, tname, sizeof tname));
p = clientrxmit(&reqmsg, buf);
if(p == nil){
if(debug)
dnslog("%d: duplicate", req.id);
goto freereq;
}
if (Logqueries) {
RR *rr;
for (rr = reqmsg.qd; rr; rr = rr->next)
syslog(0, "dnsq", "id %d: (%I/%d) %d %s %s",
req.id, buf, uh->rport[0]<<8 |
uh->rport[1], reqmsg.id,
reqmsg.qd->owner->name,
rrname(reqmsg.qd->type, tname,
sizeof tname));
}
/* loop through each question */
while(reqmsg.qd){
memset(&repmsg, 0, sizeof repmsg);
switch(op){
case Oquery:
dnserver(&reqmsg, &repmsg, &req, buf, rcode);
break;
case Onotify:
dnnotify(&reqmsg, &repmsg, &req);
break;
}
/* send reply on fd to address in buf's udp hdr */
reply(fd, buf, &repmsg, &req);
freeanswers(&repmsg);
}
p->inuse = 0;
freereq:
free(req.from);
req.from = nil;
freeanswers(&reqmsg);
if(req.isslave){
putactivity(0);
_exits(0);
}
}
}
