static void addr_callback(void *arg, int status, int timeouts,
unsigned char *abuf, int alen)
{
struct addr_query *aquery = (struct addr_query *) arg;
struct hostent *host;
size_t addrlen;
aquery->timeouts += timeouts;
if (status == ARES_SUCCESS)
{
if (aquery->addr.family == AF_INET)
{
addrlen = sizeof(struct in_addr);
status = ares_parse_ptr_reply(abuf, alen, &aquery->addr.addrV4,
(int)addrlen, AF_INET, &host);
}
else
{
addrlen = sizeof(struct in6_addr);
status = ares_parse_ptr_reply(abuf, alen, &aquery->addr.addrV6,
(int)addrlen, AF_INET6, &host);
}
end_aquery(aquery, status, host);
}
else if (status == ARES_EDESTRUCTION)
end_aquery(aquery, status, NULL);
else
next_lookup(aquery);
}
static void host_callback(void *arg, int status, int timeouts,
unsigned char *abuf, int alen)
{
struct host_query *hquery = (struct host_query *) arg;
ares_channel channel = hquery->channel;
struct hostent *host = NULL;
hquery->timeouts += timeouts;
if (status == ARES_SUCCESS)
{
if (hquery->sent_family == AF_INET)
{
status = ares_parse_a_reply(abuf, alen, &host, NULL, NULL);
if (host && channel->nsort)
sort_addresses(host, channel->sortlist, channel->nsort);
}
else if (hquery->sent_family == AF_INET6)
{
status = ares_parse_aaaa_reply(abuf, alen, &host, NULL, NULL);
if ((status == ARES_ENODATA || status == ARES_EBADRESP ||
(status == ARES_SUCCESS && host && host->h_addr_list[0] == NULL)) &&
hquery->want_family == AF_UNSPEC) {
/* The query returned something but either there were no AAAA
records (e.g. just CNAME) or the response was malformed. Try
looking up A instead. */
if (host)
ares_free_hostent(host);
hquery->sent_family = AF_INET;
ares_search(hquery->channel, hquery->name, C_IN, T_A,
host_callback, hquery);
return;
}
if (host && channel->nsort)
sort6_addresses(host, channel->sortlist, channel->nsort);
}
end_hquery(hquery, status, host);
}
else if ((status == ARES_ENODATA || status == ARES_EBADRESP ||
status == ARES_ETIMEOUT) && (hquery->sent_family == AF_INET6 &&
hquery->want_family == AF_UNSPEC))
{
/* The AAAA query yielded no useful result. Now look up an A instead. */
hquery->sent_family = AF_INET;
ares_search(hquery->channel, hquery->name, C_IN, T_A, host_callback,
hquery);
}
else if (status == ARES_EDESTRUCTION)
end_hquery(hquery, status, NULL);
else
next_lookup(hquery, status);
}
static void host_callback(void *arg, int status, unsigned char *abuf, int alen)
{
struct host_query *hquery = (struct host_query *) arg;
ares_channel channel = hquery->channel;
struct hostent *host;
if (status == ARES_SUCCESS)
{
status = ares_parse_a_reply(abuf, alen, &host);
if (host && channel->nsort)
sort_addresses(host, channel->sortlist, channel->nsort);
end_hquery(hquery, status, host);
}
else if (status == ARES_EDESTRUCTION)
end_hquery(hquery, status, NULL);
else
next_lookup(hquery);
}
void ares_gethostbyname(ares_channel channel, const char *name, int family,
ares_host_callback callback, void *arg)
{
struct host_query *hquery;
/* Right now we only know how to look up Internet addresses - and unspec
means try both basically. */
switch (family) {
case AF_INET:
case AF_INET6:
case AF_UNSPEC:
break;
default:
callback(arg, ARES_ENOTIMP, 0, NULL);
return;
}
if (fake_hostent(name, family, callback, arg))
return;
/* Allocate and fill in the host query structure. */
hquery = ares_malloc(sizeof(struct host_query));
if (!hquery)
{
callback(arg, ARES_ENOMEM, 0, NULL);
return;
}
hquery->channel = channel;
hquery->name = ares_strdup(name);
hquery->want_family = family;
hquery->sent_family = -1; /* nothing is sent yet */
if (!hquery->name) {
ares_free(hquery);
callback(arg, ARES_ENOMEM, 0, NULL);
return;
}
hquery->callback = callback;
hquery->arg = arg;
hquery->remaining_lookups = channel->lookups;
hquery->timeouts = 0;
/* Start performing lookups according to channel->lookups. */
next_lookup(hquery, ARES_ECONNREFUSED /* initial error code */);
}
void ares_gethostbyname(ares_channel channel, const char *name, int family,
ares_host_callback callback, void *arg)
{
struct host_query *hquery;
/* See if request can be handled by local pseudo-domain DNS */
if (ares_local_gethostbyname(channel, name, family, callback, arg))
{
return;
}
/* Right now we only know how to look up Internet addresses. */
if (family != AF_INET)
{
callback(arg, ARES_ENOTIMP, NULL);
return;
}
if (fake_hostent(name, callback, arg))
return;
/* Allocate and fill in the host query structure. */
hquery = malloc(sizeof(struct host_query));
if (!hquery)
{
callback(arg, ARES_ENOMEM, NULL);
return;
}
hquery->channel = channel;
hquery->name = strdup(name);
if (!hquery->name)
{
free(hquery);
callback(arg, ARES_ENOMEM, NULL);
return;
}
hquery->callback = callback;
hquery->arg = arg;
hquery->remaining_lookups = channel->lookups;
/* Start performing lookups according to channel->lookups. */
next_lookup(hquery);
}
void ares_gethostbyaddr(ares_channel channel, const void *addr, int addrlen,
int family, ares_host_callback callback, void *arg)
{
struct addr_query *aquery;
if (family != AF_INET && family != AF_INET6)
{
callback(arg, ARES_ENOTIMP, 0, NULL);
return;
}
if ((family == AF_INET && addrlen != sizeof(struct in_addr)) ||
(family == AF_INET6 && addrlen != sizeof(struct in6_addr)))
{
callback(arg, ARES_ENOTIMP, 0, NULL);
return;
}
aquery = malloc(sizeof(struct addr_query));
if (!aquery)
{
callback(arg, ARES_ENOMEM, 0, NULL);
return;
}
aquery->channel = channel;
if (family == AF_INET)
memcpy(&aquery->addr.addrV4, addr, sizeof(struct in_addr));
else
memcpy(&aquery->addr.addrV6, addr, sizeof(struct in6_addr));
aquery->addr.family = family;
aquery->callback = callback;
aquery->arg = arg;
aquery->remaining_lookups = channel->lookups;
aquery->timeouts = 0;
next_lookup(aquery);
}
