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#include <u.h>
#include <libc.h>
#include <ip.h>
#include <thread.h>
#include "netbios.h"
static struct {
int thread;
QLock;
int fd;
} udp = { -1 };
typedef struct Listen Listen;
struct Listen {
NbName to;
int (*deliver)(void *magic, NbDgram *s);
void *magic;
Listen *next;
};
static struct {
Lock;
ushort id;
} id;
struct {
QLock;
NbnsTransaction *head;
} transactionlist;
static void
udplistener(void *)
{
for (;;) {
uchar msg[Udphdrsize + 576];
int len = read(udp.fd, msg, sizeof(msg));
if (len < 0)
break;
if (len >= nbudphdrsize) {
NbnsMessage *s;
// Udphdr *uh;
uchar *p;
// uh = (Udphdr*)msg;
p = msg + nbudphdrsize;
len -= nbudphdrsize;
s = nbnsconvM2S(p, len);
if (s) {
//print("%I:%d -> %I:%d\n", uh->raddr, nhgets(uh->rport), uh->laddr, nhgets(uh->lport));
//nbnsdumpmessage(s);
if (s->response) {
NbnsTransaction *t;
qlock(&transactionlist);
for (t = transactionlist.head; t; t = t->next)
if (t->id == s->id)
break;
if (t)
sendp(t->c, s);
else
nbnsmessagefree(&s);
qunlock(&transactionlist);
}
else
nbnsmessagefree(&s);
}
}
}
}
static char *
startlistener(void)
{
qlock(&udp);
if (udp.thread < 0) {
char *e;
e = nbudpannounce(NbnsPort, &udp.fd);
if (e) {
qunlock(&udp);
return e;
}
udp.thread = proccreate(udplistener, nil, 16384);
}
qunlock(&udp);
return nil;
}
ushort
nbnsnextid(void)
{
ushort rv;
lock(&id);
rv = id.id++;
unlock(&id);
return rv;
}
NbnsTransaction *
nbnstransactionnew(NbnsMessage *s, uchar *ipaddr)
{
NbnsTransaction *t;
uchar msg[Udphdrsize + 576];
Udphdr *u;
int len;
startlistener();
len = nbnsconvS2M(s, msg + nbudphdrsize, sizeof(msg) - nbudphdrsize);
if (len == 0)
return 0;
t = mallocz(sizeof(*t), 1);
if (t == nil)
return nil;
t->id = s->id;
t->c = chancreate(sizeof(NbnsMessage *), 3);
if (t->c == nil) {
free(t);
return nil;
}
qlock(&transactionlist);
t->next = transactionlist.head;
transactionlist.head = t;
qunlock(&transactionlist);
u = (Udphdr *)msg;
ipmove(u->laddr, nbglobals.myipaddr);
hnputs(u->lport, NbnsPort);
if (s->broadcast || ipaddr == nil)
ipmove(u->raddr, nbglobals.bcastaddr);
else
ipmove(u->raddr, ipaddr);
hnputs(u->rport, NbnsPort);
write(udp.fd, msg, len + nbudphdrsize);
return t;
}
void
nbnstransactionfree(NbnsTransaction **tp)
{
NbnsTransaction **tp2;
NbnsMessage *s;
NbnsTransaction *t;
t = *tp;
if (t) {
qlock(&transactionlist);
while ((s = nbrecvp(t->c)) != nil)
nbnsmessagefree(&s);
for (tp2 = &transactionlist.head; *tp2 && *tp2 != t; tp2 = &(*tp2)->next)
;
if (*tp2) {
*tp2 = t->next;
free(t);
}
qunlock(&transactionlist);
*tp = nil;
}
}
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