Curl_addrinfo *Curl_resolv(struct SessionHandle *data,
char *hostname,
int port,
char **bufp)
{
char *entry_id = NULL;
struct curl_dns_cache_entry *p = NULL;
ssize_t entry_len;
time_t now;
/* If the host cache timeout is 0, we don't do DNS cach'ing
so fall through */
if (data->set.dns_cache_timeout == 0) {
return Curl_getaddrinfo(data, hostname, port, bufp);
}
/* Create an entry id, based upon the hostname and port */
entry_len = strlen(hostname);
entry_id = _create_hostcache_id(hostname, port, &entry_len);
/* If we can't create the entry id, don't cache, just fall-through
to the plain Curl_getaddrinfo() */
if (!entry_id) {
return Curl_getaddrinfo(data, hostname, port, bufp);
}
time(&now);
/* See if its already in our dns cache */
if (entry_id && curl_hash_find(data->hostcache, entry_id, entry_len+1, (void **) &p)) {
/* Do we need to check for a cache timeout? */
if (data->set.dns_cache_timeout != -1) {
/* Return if the entry has not timed out */
if ((now - p->timestamp) < data->set.dns_cache_timeout) {
_hostcache_return(p->addr);
}
}
else {
_hostcache_return(p->addr);
}
}
/* Create a new cache entry */
p = (struct curl_dns_cache_entry *) malloc(sizeof(struct curl_dns_cache_entry));
if (!p) {
_hostcache_return(NULL);
}
p->addr = Curl_getaddrinfo(data, hostname, port, bufp);
if (!p->addr) {
free(p);
_hostcache_return(NULL);
}
p->timestamp = now;
/* Save it in our host cache */
curl_hash_update(data->hostcache, entry_id, entry_len+1, (const void *) p);
_hostcache_return(p->addr);
}
int Curl_resolv(struct connectdata *conn,
char *hostname,
int port,
struct Curl_dns_entry **entry)
{
char *entry_id = NULL;
struct Curl_dns_entry *dns = NULL;
size_t entry_len;
int wait;
struct SessionHandle *data = conn->data;
CURLcode result;
int rc;
*entry = NULL;
#ifdef HAVE_SIGSETJMP
/* this allows us to time-out from the name resolver, as the timeout
will generate a signal and we will siglongjmp() from that here */
if(!data->set.no_signal && sigsetjmp(curl_jmpenv, 1)) {
/* this is coming from a siglongjmp() */
failf(data, "name lookup timed out");
return CURLRESOLV_ERROR;
}
#endif
/* 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 CURLRESOLV_ERROR;
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->hostcache, entry_id, entry_len+1);
if(data->share)
Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
/* free the allocated entry_id again */
free(entry_id);
/* See whether the returned entry is stale. Deliberately done after the
locked block */
if ( remove_entry_if_stale(data,dns) )
dns = NULL; /* the memory deallocation is being handled by the hash */
rc = CURLRESOLV_ERROR; /* default to failure */
if (!dns) {
/* The entry was not in the cache. Resolve it to IP address */
Curl_addrinfo *addr;
/* Check what IP specifics the app has requested and if we can provide it.
* If not, bail out. */
if(!Curl_ipvalid(data))
return CURLRESOLV_ERROR;
/* If Curl_getaddrinfo() returns NULL, 'wait' 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, hostname, port, &wait);
if (!addr) {
if(wait) {
/* 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_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;
}
}
else {
if(data->share)
Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
dns->inuse++; /* we use it! */
if(data->share)
Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
rc = CURLRESOLV_RESOLVED;
}
*entry = dns;
return rc;
}
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_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;
}
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;
}
