/*
* 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;
}
int Curl_resolv(struct connectdata *conn,
const char *hostname,
int port,
struct Curl_dns_entry **entry)
{
struct Curl_dns_entry *dns = NULL;
struct SessionHandle *data = conn->data;
CURLcode result;
int rc = CURLRESOLV_ERROR; /* default to failure */
*entry = NULL;
if(data->share)
Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
dns = fetch_addr(conn, hostname, port);
if(dns) {
infof(data, "Hostname %s was found in DNS cache\n", hostname);
dns->inuse++; /* we use it! */
rc = CURLRESOLV_RESOLVED;
}
if(data->share)
Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
if(!dns) {
/* The entry was not in the cache. Resolve it to IP address */
Curl_addrinfo *addr;
int respwait;
/* Check what IP specifics the app has requested and if we can provide it.
* If not, bail out. */
if(!Curl_ipvalid(conn))
return CURLRESOLV_ERROR;
/* If Curl_getaddrinfo() returns NULL, 'respwait' might be set to a
non-zero value indicating that we need to wait for the response to the
resolve call */
addr = Curl_getaddrinfo(conn,
#ifdef DEBUGBUILD
(data->set.str[STRING_DEVICE]
&& !strcmp(data->set.str[STRING_DEVICE],
"LocalHost"))?"localhost":
#endif
hostname, port, &respwait);
if(!addr) {
if(respwait) {
/* the response to our resolve call will come asynchronously at
a later time, good or bad */
/* First, check that we haven't received the info by now */
result = Curl_resolver_is_resolved(conn, &dns);
if(result) /* error detected */
return CURLRESOLV_ERROR;
if(dns)
rc = CURLRESOLV_RESOLVED; /* pointer provided */
else
rc = CURLRESOLV_PENDING; /* no info yet */
}
}
else {
if(data->share)
Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
/* we got a response, store it in the cache */
dns = Curl_cache_addr(data, addr, hostname, port);
if(data->share)
Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
if(!dns)
/* returned failure, bail out nicely */
Curl_freeaddrinfo(addr);
else
rc = CURLRESOLV_RESOLVED;
}
}
*entry = dns;
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;
}
int Curl_resolv(struct connectdata *conn,
const char *hostname,
int port,
struct Curl_dns_entry **entry)
{
char *entry_id = NULL;
struct Curl_dns_entry *dns = NULL;
size_t entry_len;
struct SessionHandle *data = conn->data;
CURLcode result;
int rc = CURLRESOLV_ERROR; /* default to failure */
*entry = NULL;
/* Create an entry id, based upon the hostname and port */
entry_id = create_hostcache_id(hostname, port);
/* If we can't create the entry id, fail */
if(!entry_id)
return rc;
entry_len = strlen(entry_id);
if(data->share)
Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
/* See if its already in our dns cache */
dns = Curl_hash_pick(data->dns.hostcache, entry_id, entry_len+1);
/* free the allocated entry_id again */
free(entry_id);
/* See whether the returned entry is stale. Done before we release lock */
if(remove_entry_if_stale(data, dns))
dns = NULL; /* the memory deallocation is being handled by the hash */
if(dns) {
dns->inuse++; /* we use it! */
rc = CURLRESOLV_RESOLVED;
}
if(data->share)
Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
if(!dns) {
/* The entry was not in the cache. Resolve it to IP address */
Curl_addrinfo *addr;
int respwait;
/* Check what IP specifics the app has requested and if we can provide it.
* If not, bail out. */
if(!Curl_ipvalid(conn))
return CURLRESOLV_ERROR;
/* If Curl_getaddrinfo() returns NULL, 'respwait' might be set to a
non-zero value indicating that we need to wait for the response to the
resolve call */
addr = Curl_getaddrinfo(conn,
#ifdef DEBUGBUILD
(data->set.str[STRING_DEVICE]
&& !strcmp(data->set.str[STRING_DEVICE],
"LocalHost"))?"localhost":
#endif
hostname, port, &respwait);
if(!addr) {
if(respwait) {
/* the response to our resolve call will come asynchronously at
a later time, good or bad */
/* First, check that we haven't received the info by now */
result = Curl_resolver_is_resolved(conn, &dns);
if(result) /* error detected */
return CURLRESOLV_ERROR;
if(dns)
rc = CURLRESOLV_RESOLVED; /* pointer provided */
else
rc = CURLRESOLV_PENDING; /* no info yet */
}
}
else {
if(data->share)
Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
/* we got a response, store it in the cache */
dns = Curl_cache_addr(data, addr, hostname, port);
if(data->share)
Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
if(!dns)
/* returned failure, bail out nicely */
Curl_freeaddrinfo(addr);
else
rc = CURLRESOLV_RESOLVED;
}
}
*entry = dns;
return rc;
}
