/*
* Curl_resolver_is_resolved() is called repeatedly to check if a previous
* name resolve request has completed. It should also make sure to time-out if
* the operation seems to take too long.
*
* Returns normal CURLcode errors.
*/
CURLcode Curl_resolver_is_resolved(struct connectdata *conn,
struct Curl_dns_entry **dns)
{
struct SessionHandle *data = conn->data;
struct ResolverResults *res = (struct ResolverResults *)
conn->async.os_specific;
*dns = NULL;
waitperform(conn, 0);
if(res && !res->num_pending) {
(void)Curl_addrinfo_callback(conn, res->last_status, res->temp_ai);
/* temp_ai ownership is moved to the connection, so we need not free-up
them */
res->temp_ai = NULL;
destroy_async_data(&conn->async);
if(!conn->async.dns) {
failf(data, "Could not resolve %s: %s (%s)",
conn->bits.proxy?"proxy":"host",
conn->host.dispname,
ares_strerror(conn->async.status));
return conn->bits.proxy?CURLE_COULDNT_RESOLVE_PROXY:
CURLE_COULDNT_RESOLVE_HOST;
}
*dns = conn->async.dns;
}
return CURLE_OK;
}
/*
* Curl_resolver_is_resolved() is called repeatedly to check if a previous
* name resolve request has completed. It should also make sure to time-out if
* the operation seems to take too long.
*
* Returns normal CURLcode errors.
*/
CURLcode Curl_resolver_is_resolved(struct connectdata *conn,
struct Curl_dns_entry **dns)
{
struct Curl_easy *data = conn->data;
struct ResolverResults *res = (struct ResolverResults *)
conn->async.os_specific;
CURLcode result = CURLE_OK;
if(dns)
*dns = NULL;
waitperform(conn, 0);
/* Now that we've checked for any last minute results above, see if there are
any responses still pending when the EXPIRE_HAPPY_EYEBALLS_DNS timer
expires. */
if(res
&& res->num_pending
/* This is only set to non-zero if the timer was started. */
&& (res->happy_eyeballs_dns_time.tv_sec
|| res->happy_eyeballs_dns_time.tv_usec)
&& (Curl_timediff(Curl_now(), res->happy_eyeballs_dns_time)
>= HAPPY_EYEBALLS_DNS_TIMEOUT)) {
/* Remember that the EXPIRE_HAPPY_EYEBALLS_DNS timer is no longer
running. */
memset(
&res->happy_eyeballs_dns_time, 0, sizeof(res->happy_eyeballs_dns_time));
/* Cancel the raw c-ares request, which will fire query_completed_cb() with
ARES_ECANCELLED synchronously for all pending responses. This will
leave us with res->num_pending == 0, which is perfect for the next
block. */
ares_cancel((ares_channel)data->state.resolver);
DEBUGASSERT(res->num_pending == 0);
}
if(res && !res->num_pending) {
if(dns) {
(void)Curl_addrinfo_callback(conn, res->last_status, res->temp_ai);
/* temp_ai ownership is moved to the connection, so we need not free-up
them */
res->temp_ai = NULL;
}
if(!conn->async.dns) {
failf(data, "Could not resolve: %s (%s)",
conn->async.hostname, ares_strerror(conn->async.status));
result = conn->bits.proxy?CURLE_COULDNT_RESOLVE_PROXY:
CURLE_COULDNT_RESOLVE_HOST;
}
else if(dns)
*dns = conn->async.dns;
destroy_async_data(&conn->async);
}
return result;
}
/*
* Curl_is_resolved() is called repeatedly to check if a previous name resolve
* request has completed. It should also make sure to time-out if the
* operation seems to take too long.
*
* Returns normal CURLcode errors.
*/
CURLcode Curl_is_resolved(struct connectdata *conn,
struct Curl_dns_entry **dns)
{
struct SessionHandle *data = conn->data;
*dns = NULL;
waitperform(conn, 0);
if(conn->async.done) {
/* we're done, kill the ares handle */
if(!conn->async.dns) {
failf(data, "Could not resolve host: %s (%s)", conn->host.dispname,
ares_strerror(conn->async.status));
return CURLE_COULDNT_RESOLVE_HOST;
}
*dns = conn->async.dns;
}
return CURLE_OK;
}
/*
* Curl_resolver_wait_resolv()
*
* waits for a resolve to finish. This function should be avoided since using
* this risk getting the multi interface to "hang".
*
* If 'entry' is non-NULL, make it point to the resolved dns entry
*
* Returns CURLE_COULDNT_RESOLVE_HOST if the host was not resolved, and
* CURLE_OPERATION_TIMEDOUT if a time-out occurred.
*/
CURLcode Curl_resolver_wait_resolv(struct connectdata *conn,
struct Curl_dns_entry **entry)
{
CURLcode rc=CURLE_OK;
struct SessionHandle *data = conn->data;
long timeout;
struct timeval now = Curl_tvnow();
struct Curl_dns_entry *temp_entry;
timeout = Curl_timeleft(data, &now, TRUE);
if(!timeout)
timeout = CURL_TIMEOUT_RESOLVE * 1000; /* default name resolve timeout */
/* Wait for the name resolve query to complete. */
for(;;) {
struct timeval *tvp, tv, store;
long timediff;
int itimeout;
int timeout_ms;
itimeout = (timeout > (long)INT_MAX) ? INT_MAX : (int)timeout;
store.tv_sec = itimeout/1000;
store.tv_usec = (itimeout%1000)*1000;
tvp = ares_timeout((ares_channel)data->state.resolver, &store, &tv);
/* use the timeout period ares returned to us above if less than one
second is left, otherwise just use 1000ms to make sure the progress
callback gets called frequent enough */
if(!tvp->tv_sec)
timeout_ms = (int)(tvp->tv_usec/1000);
else
timeout_ms = 1000;
waitperform(conn, timeout_ms);
Curl_resolver_is_resolved(conn,&temp_entry);
if(conn->async.done)
break;
if(Curl_pgrsUpdate(conn)) {
rc = CURLE_ABORTED_BY_CALLBACK;
timeout = -1; /* trigger the cancel below */
}
else {
struct timeval now2 = Curl_tvnow();
timediff = Curl_tvdiff(now2, now); /* spent time */
timeout -= timediff?timediff:1; /* always deduct at least 1 */
now = now2; /* for next loop */
}
if(timeout < 0) {
/* our timeout, so we cancel the ares operation */
ares_cancel((ares_channel)data->state.resolver);
break;
}
}
/* Operation complete, if the lookup was successful we now have the entry
in the cache. */
if(entry)
*entry = conn->async.dns;
if(!conn->async.dns) {
/* a name was not resolved */
if((timeout < 0) || (conn->async.status == ARES_ETIMEOUT)) {
if(conn->bits.proxy) {
failf(data, "Resolving proxy timed out: %s", conn->proxy.dispname);
rc = CURLE_COULDNT_RESOLVE_PROXY;
}
else {
failf(data, "Resolving host timed out: %s", conn->host.dispname);
rc = CURLE_COULDNT_RESOLVE_HOST;
}
}
else if(conn->async.done) {
if(conn->bits.proxy) {
failf(data, "Could not resolve proxy: %s (%s)", conn->proxy.dispname,
ares_strerror(conn->async.status));
rc = CURLE_COULDNT_RESOLVE_PROXY;
}
else {
failf(data, "Could not resolve host: %s (%s)", conn->host.dispname,
ares_strerror(conn->async.status));
rc = CURLE_COULDNT_RESOLVE_HOST;
}
}
else
rc = CURLE_OPERATION_TIMEDOUT;
/* close the connection, since we can't return failure here without
cleaning up this connection properly */
conn->bits.close = TRUE;
}
return rc;
}
/*
* Curl_resolver_wait_resolv()
*
* waits for a resolve to finish. This function should be avoided since using
* this risk getting the multi interface to "hang".
*
* If 'entry' is non-NULL, make it point to the resolved dns entry
*
* Returns CURLE_COULDNT_RESOLVE_HOST if the host was not resolved, and
* CURLE_OPERATION_TIMEDOUT if a time-out occurred.
*/
CURLcode Curl_resolver_wait_resolv(struct connectdata *conn,
struct Curl_dns_entry **entry)
{
CURLcode result = CURLE_OK;
struct Curl_easy *data = conn->data;
long timeout;
struct timeval now = Curl_tvnow();
struct Curl_dns_entry *temp_entry;
if(entry)
*entry = NULL; /* clear on entry */
timeout = Curl_timeleft(data, &now, TRUE);
if(timeout < 0) {
/* already expired! */
connclose(conn, "Timed out before name resolve started");
return CURLE_OPERATION_TIMEDOUT;
}
if(!timeout)
timeout = CURL_TIMEOUT_RESOLVE * 1000; /* default name resolve timeout */
/* Wait for the name resolve query to complete. */
while(!result) {
struct timeval *tvp, tv, store;
long timediff;
int itimeout;
int timeout_ms;
itimeout = (timeout > (long)INT_MAX) ? INT_MAX : (int)timeout;
store.tv_sec = itimeout/1000;
store.tv_usec = (itimeout%1000)*1000;
tvp = ares_timeout((ares_channel)data->state.resolver, &store, &tv);
/* use the timeout period ares returned to us above if less than one
second is left, otherwise just use 1000ms to make sure the progress
callback gets called frequent enough */
if(!tvp->tv_sec)
timeout_ms = (int)(tvp->tv_usec/1000);
else
timeout_ms = 1000;
waitperform(conn, timeout_ms);
result = Curl_resolver_is_resolved(conn, &temp_entry);
if(result || conn->async.done)
break;
if(Curl_pgrsUpdate(conn))
result = CURLE_ABORTED_BY_CALLBACK;
else {
struct timeval now2 = Curl_tvnow();
timediff = Curl_tvdiff(now2, now); /* spent time */
timeout -= timediff?timediff:1; /* always deduct at least 1 */
now = now2; /* for next loop */
}
if(timeout < 0)
result = CURLE_OPERATION_TIMEDOUT;
}
if(result)
/* failure, so we cancel the ares operation */
ares_cancel((ares_channel)data->state.resolver);
/* Operation complete, if the lookup was successful we now have the entry
in the cache. */
if(entry)
*entry = conn->async.dns;
if(result)
/* close the connection, since we can't return failure here without
cleaning up this connection properly.
TODO: remove this action from here, it is not a name resolver decision.
*/
connclose(conn, "c-ares resolve failed");
return result;
}
