/*
* 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.
*/
CURLcode Curl_resolver_is_resolved(struct connectdata *conn,
struct Curl_dns_entry **entry)
{
struct Curl_easy *data = conn->data;
struct thread_data *td = (struct thread_data*) conn->async.os_specific;
int done = 0;
*entry = NULL;
if(!td) {
DEBUGASSERT(td);
return CURLE_COULDNT_RESOLVE_HOST;
}
Curl_mutex_acquire(td->tsd.mtx);
done = td->tsd.done;
Curl_mutex_release(td->tsd.mtx);
if(done) {
getaddrinfo_complete(conn);
if(!conn->async.dns) {
CURLcode result = resolver_error(conn);
destroy_async_data(&conn->async);
return result;
}
destroy_async_data(&conn->async);
*entry = conn->async.dns;
}
else {
/* poll for name lookup done with exponential backoff up to 250ms */
timediff_t elapsed = Curl_timediff(Curl_now(),
data->progress.t_startsingle);
if(elapsed < 0)
elapsed = 0;
if(td->poll_interval == 0)
/* Start at 1ms poll interval */
td->poll_interval = 1;
else if(elapsed >= td->interval_end)
/* Back-off exponentially if last interval expired */
td->poll_interval *= 2;
if(td->poll_interval > 250)
td->poll_interval = 250;
td->interval_end = elapsed + td->poll_interval;
Curl_expire(conn->data, td->poll_interval, EXPIRE_ASYNC_NAME);
}
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 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_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
*
* This is the version for resolves-in-a-thread.
*/
CURLcode Curl_resolver_wait_resolv(struct connectdata *conn,
struct Curl_dns_entry **entry)
{
struct thread_data *td = (struct thread_data*) conn->async.os_specific;
CURLcode result = CURLE_OK;
DEBUGASSERT(conn && td);
/* wait for the thread to resolve the name */
if(Curl_thread_join(&td->thread_hnd))
result = getaddrinfo_complete(conn);
else
DEBUGASSERT(0);
conn->async.done = TRUE;
if(entry)
*entry = conn->async.dns;
if(!conn->async.dns)
/* a name was not resolved, report error */
result = resolver_error(conn);
destroy_async_data(&conn->async);
if(!conn->async.dns)
connclose(conn, "asynch resolve failed");
return result;
}
/*
* 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;
}
/*
* init_resolve_thread() starts a new thread that performs the actual
* resolve. This function returns before the resolve is done.
*
* Returns FALSE in case of failure, otherwise TRUE.
*/
static bool init_resolve_thread(struct connectdata *conn,
const char *hostname, int port,
const struct addrinfo *hints)
{
struct thread_data *td = calloc(1, sizeof(struct thread_data));
int err = ENOMEM;
conn->async.os_specific = (void *)td;
if(!td)
goto errno_exit;
conn->async.port = port;
conn->async.done = FALSE;
conn->async.status = 0;
conn->async.dns = NULL;
td->thread_hnd = curl_thread_t_null;
if(!init_thread_sync_data(td, hostname, port, hints)) {
conn->async.os_specific = NULL;
free(td);
goto errno_exit;
}
free(conn->async.hostname);
conn->async.hostname = strdup(hostname);
if(!conn->async.hostname)
goto err_exit;
/* The thread will set this to 1 when complete. */
td->tsd.done = 0;
#ifdef HAVE_GETADDRINFO
td->thread_hnd = Curl_thread_create(getaddrinfo_thread, &td->tsd);
#else
td->thread_hnd = Curl_thread_create(gethostbyname_thread, &td->tsd);
#endif
if(!td->thread_hnd) {
/* The thread never started, so mark it as done here for proper cleanup. */
td->tsd.done = 1;
err = errno;
goto err_exit;
}
return TRUE;
err_exit:
destroy_async_data(&conn->async);
errno_exit:
errno = err;
return FALSE;
}
/*
* init_resolve_thread() starts a new thread that performs the actual
* resolve. This function returns before the resolve is done.
*
* Returns FALSE in case of failure, otherwise TRUE.
*/
static bool init_resolve_thread (struct connectdata *conn,
const char *hostname, int port,
const struct addrinfo *hints)
{
struct thread_data *td = calloc(1, sizeof(struct thread_data));
int err = RESOLVER_ENOMEM;
conn->async.os_specific = (void*) td;
if(!td)
goto err_exit;
conn->async.port = port;
conn->async.done = FALSE;
conn->async.status = 0;
conn->async.dns = NULL;
td->thread_hnd = curl_thread_t_null;
if(!init_thread_sync_data(td, hostname, port, hints))
goto err_exit;
free(conn->async.hostname);
conn->async.hostname = strdup(hostname);
if(!conn->async.hostname)
goto err_exit;
#ifdef HAVE_GETADDRINFO
td->thread_hnd = Curl_thread_create(getaddrinfo_thread, &td->tsd);
#else
td->thread_hnd = Curl_thread_create(gethostbyname_thread, &td->tsd);
#endif
if(!td->thread_hnd) {
#ifndef _WIN32_WCE
err = errno;
#endif
goto err_exit;
}
return TRUE;
err_exit:
destroy_async_data(&conn->async);
SET_ERRNO(err);
return FALSE;
}
/*
* 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
*
* This is the version for resolves-in-a-thread.
*/
CURLcode Curl_resolver_wait_resolv(struct connectdata *conn,
struct Curl_dns_entry **entry)
{
struct thread_data *td = (struct thread_data*) conn->async.os_specific;
CURLcode rc = CURLE_OK;
DEBUGASSERT(conn && td);
/* wait for the thread to resolve the name */
if(Curl_thread_join(&td->thread_hnd))
rc = getaddrinfo_complete(conn);
else
DEBUGASSERT(0);
conn->async.done = TRUE;
if(entry)
*entry = conn->async.dns;
if(!conn->async.dns) {
/* a name was not resolved */
if(conn->bits.httpproxy) {
resolver_error(conn, "proxy");
rc = CURLE_COULDNT_RESOLVE_PROXY;
}
else {
resolver_error(conn, "host");
rc = CURLE_COULDNT_RESOLVE_HOST;
}
}
destroy_async_data(&conn->async);
if(!conn->async.dns)
conn->bits.close = TRUE;
return (rc);
}
/*
* Cancel all possibly still on-going resolves for this connection.
*/
void Curl_resolver_cancel(struct connectdata *conn)
{
if(conn && conn->data && conn->data->state.resolver)
ares_cancel((ares_channel)conn->data->state.resolver);
destroy_async_data(&conn->async);
}
/*
* Cancel all possibly still on-going resolves for this connection.
*/
void Curl_resolver_cancel(struct connectdata *conn)
{
destroy_async_data(&conn->async);
}
/*
* Cancel all possibly still on-going resolves for this connection.
*/
void Curl_resolver_cancel(CURL *data)
{
struct connectdata *conn = data->easy_conn;
if(conn)
destroy_async_data(&conn->async);
}
