static void handle_packet(AvahiWideAreaLookupEngine *e, AvahiDnsPacket *p) {
AvahiWideAreaLookup *l = NULL;
int i, r;
AvahiBrowserEvent final_event = AVAHI_BROWSER_ALL_FOR_NOW;
assert(e);
assert(p);
/* Some superficial validity tests */
if (avahi_dns_packet_check_valid(p) < 0 || avahi_dns_packet_is_query(p)) {
avahi_log_warn(__FILE__": Ignoring invalid response for wide area datagram.");
goto finish;
}
/* Look for the lookup that issued this query */
if (!(l = find_lookup(e, avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ID))) || l->dead)
goto finish;
/* Check whether this a packet indicating a failure */
if ((r = avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_FLAGS) & 15) != 0 ||
avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ANCOUNT) == 0) {
avahi_server_set_errno(e->server, r == 0 ? AVAHI_ERR_NOT_FOUND : map_dns_error(r));
/* Tell the user about the failure */
final_event = AVAHI_BROWSER_FAILURE;
/* We go on here, since some of the records contained in the
reply might be interesting in some way */
}
/* Skip over the question */
for (i = (int) avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_QDCOUNT); i > 0; i--) {
AvahiKey *k;
if (!(k = avahi_dns_packet_consume_key(p, NULL))) {
avahi_log_warn(__FILE__": Wide area response packet too short or invalid while reading question key. (Maybe a UTF-8 problem?)");
avahi_server_set_errno(e->server, AVAHI_ERR_INVALID_PACKET);
final_event = AVAHI_BROWSER_FAILURE;
goto finish;
}
avahi_key_unref(k);
}
/* Process responses */
for (i = (int) avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ANCOUNT) +
(int) avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_NSCOUNT) +
(int) avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ARCOUNT); i > 0; i--) {
AvahiRecord *rr;
if (!(rr = avahi_dns_packet_consume_record(p, NULL))) {
avahi_log_warn(__FILE__": Wide area response packet too short or invalid while reading response record. (Maybe a UTF-8 problem?)");
avahi_server_set_errno(e->server, AVAHI_ERR_INVALID_PACKET);
final_event = AVAHI_BROWSER_FAILURE;
goto finish;
}
add_to_cache(e, rr);
avahi_record_unref(rr);
}
finish:
if (l && !l->dead) {
if (l->callback)
l->callback(e, final_event, AVAHI_LOOKUP_RESULT_WIDE_AREA, NULL, l->userdata);
lookup_stop(l);
}
}
void next_token(state *s) {
s->type = TOK_NULL;
if (!*s->next){
s->type = TOK_END;
return;
}
do {
/* Try reading a number. */
if ((s->next[0] >= '0' && s->next[0] <= '9') || s->next[0] == '.') {
s->value = strtod(s->next, (char**)&s->next);
s->type = TOK_NUMBER;
} else {
/* Look for a variable or builtin function call. */
if (s->next[0] >= 'a' && s->next[0] <= 'z') {
const char *start;
start = s->next;
while ((s->next[0] >= 'a' && s->next[0] <= 'z') || (s->next[0] >= '0' && s->next[0] <= '9')) s->next++;
const te_variable *var = find_lookup(s, start, s->next - start);
if (!var) var = find_builtin(start, s->next - start);
if (!var) {
s->type = TOK_ERROR;
} else {
switch(TYPE_MASK(var->type))
{
case TE_VARIABLE:
s->type = TOK_VARIABLE;
s->bound = var->address;
break;
case TE_CLOSURE0: case TE_CLOSURE1: case TE_CLOSURE2: case TE_CLOSURE3:
case TE_CLOSURE4: case TE_CLOSURE5: case TE_CLOSURE6: case TE_CLOSURE7:
s->context = var->context;
case TE_FUNCTION0: case TE_FUNCTION1: case TE_FUNCTION2: case TE_FUNCTION3:
case TE_FUNCTION4: case TE_FUNCTION5: case TE_FUNCTION6: case TE_FUNCTION7:
s->type = var->type;
s->function = var->address;
break;
}
}
} else {
/* Look for an operator or special character. */
switch (s->next++[0]) {
case '+': s->type = TOK_INFIX; s->function = add; break;
case '-': s->type = TOK_INFIX; s->function = sub; break;
case '*': s->type = TOK_INFIX; s->function = mul; break;
case '/': s->type = TOK_INFIX; s->function = divide; break;
case '^': s->type = TOK_INFIX; s->function = pow; break;
case '%': s->type = TOK_INFIX; s->function = fmod; break;
case '(': s->type = TOK_OPEN; break;
case ')': s->type = TOK_CLOSE; break;
case ',': s->type = TOK_SEP; break;
case ' ': case '\t': case '\n': case '\r': break;
default: s->type = TOK_ERROR; break;
}
}
}
} while (s->type == TOK_NULL);
}
AvahiWideAreaLookup *avahi_wide_area_lookup_new(
AvahiWideAreaLookupEngine *e,
AvahiKey *key,
AvahiWideAreaLookupCallback callback,
void *userdata) {
struct timeval tv;
AvahiWideAreaLookup *l, *t;
uint8_t *p;
assert(e);
assert(key);
assert(callback);
assert(userdata);
l = avahi_new(AvahiWideAreaLookup, 1);
l->engine = e;
l->dead = 0;
l->key = avahi_key_ref(key);
l->cname_key = avahi_key_new_cname(l->key);
l->callback = callback;
l->userdata = userdata;
/* If more than 65K wide area quries are issued simultaneously,
* this will break. This should be limited by some higher level */
for (;; e->next_id++)
if (!find_lookup(e, e->next_id))
break; /* This ID is not yet used. */
l->id = e->next_id++;
/* We keep the packet around in case we need to repeat our query */
l->packet = avahi_dns_packet_new(0);
avahi_dns_packet_set_field(l->packet, AVAHI_DNS_FIELD_ID, (uint16_t) l->id);
avahi_dns_packet_set_field(l->packet, AVAHI_DNS_FIELD_FLAGS, AVAHI_DNS_FLAGS(0, 0, 0, 0, 1, 0, 0, 0, 0, 0));
p = avahi_dns_packet_append_key(l->packet, key, 0);
assert(p);
avahi_dns_packet_set_field(l->packet, AVAHI_DNS_FIELD_QDCOUNT, 1);
if (send_to_dns_server(l, l->packet) < 0) {
avahi_log_error(__FILE__": Failed to send packet.");
avahi_dns_packet_free(l->packet);
avahi_key_unref(l->key);
if (l->cname_key)
avahi_key_unref(l->cname_key);
avahi_free(l);
return NULL;
}
l->n_send = 1;
l->time_event = avahi_time_event_new(e->server->time_event_queue, avahi_elapse_time(&tv, 500, 0), sender_timeout_callback, l);
avahi_hashmap_insert(e->lookups_by_id, &l->id, l);
t = avahi_hashmap_lookup(e->lookups_by_key, l->key);
AVAHI_LLIST_PREPEND(AvahiWideAreaLookup, by_key, t, l);
avahi_hashmap_replace(e->lookups_by_key, avahi_key_ref(l->key), t);
AVAHI_LLIST_PREPEND(AvahiWideAreaLookup, lookups, e->lookups, l);
return l;
}
