move Curl_share_lock and ref counting into Curl_fetch_addr (b4be97fb) · Commits · CYBER - Cyber Security / TS 103 523 MSP / TLMSP / TLMSP curl

lib/hostip.c

+52 −20

Original line number	Diff line number	Diff line
		@@ -311,19 +311,9 @@ remove_entry_if_stale(struct SessionHandle data, struct Curl_dns_entry dns)
		sigjmp_buf curl_jmpenv;
		#endif

		/*
		* Curl_fetch_addr() fetches a 'Curl_dns_entry' already in the DNS cache.
		*
		* Curl_resolv() checks initially and multi_runsingle() checks each time
		* it discovers the handle in the state WAITRESOLVE whether the hostname
		* has already been resolved and the address has already been stored in
		* the DNS cache. This short circuits waiting for a lot of pending
		* lookups for the same hostname requested by different handles.
		*
		* Returns the Curl_dns_entry entry pointer or NULL if not in the cache.
		*/
		struct Curl_dns_entry *
		Curl_fetch_addr(struct connectdata *conn,
		/* lookup address, returns entry if found and not stale */
		static struct Curl_dns_entry *
		fetch_addr(struct connectdata *conn,
		const char *hostname,
		int port)
		{
		@@ -344,16 +334,58 @@ Curl_fetch_addr(struct connectdata *conn,
		/* 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);

		if(dns && (data->set.dns_cache_timeout != -1)) {
		/* See whether the returned entry is stale. Done before we release lock */
		stale = remove_entry_if_stale(data, dns);
		if(stale) {
		struct hostcache_prune_data user;

		time(&user.now);
		user.cache_timeout = data->set.dns_cache_timeout;

		if(hostcache_timestamp_remove(&user, dns)) {
		infof(data, "Hostname in DNS cache was stale, zapped\n");
		dns = NULL; /* the memory deallocation is being handled by the hash */
		Curl_hash_delete(data->dns.hostcache, entry_id, entry_len+1);
		}
		}

		/* free the allocated entry_id again */
		free(entry_id);

		return dns;
		}

		/*
		* Curl_fetch_addr() fetches a 'Curl_dns_entry' already in the DNS cache.
		*
		* Curl_resolv() checks initially and multi_runsingle() checks each time
		* it discovers the handle in the state WAITRESOLVE whether the hostname
		* has already been resolved and the address has already been stored in
		* the DNS cache. This short circuits waiting for a lot of pending
		* lookups for the same hostname requested by different handles.
		*
		* Returns the Curl_dns_entry entry pointer or NULL if not in the cache.
		*
		* The returned data MUST be "unlocked" with Curl_resolv_unlock() after
		* use, or we'll leak memory!
		*/
		struct Curl_dns_entry *
		Curl_fetch_addr(struct connectdata *conn,
		const char *hostname,
		int port)
		{
		struct SessionHandle *data = conn->data;
		struct Curl_dns_entry *dns = NULL;

		if(data->share)
		Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);

		dns = fetch_addr(conn, hostname, port);

		if(dns) dns->inuse++; /* we use it! */

		if(data->share)
		Curl_share_unlock(data, CURL_LOCK_DATA_DNS);

		return dns;
		}

		@@ -451,7 +483,7 @@ int Curl_resolv(struct connectdata *conn,
		if(data->share)
		Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);

		dns = Curl_fetch_addr(conn, hostname, port);
		dns = fetch_addr(conn, hostname, port);

		if(dns) {
		infof(data, "Hostname %s was found in DNS cache\n", hostname);

lib/hostip.h

+3 −0

Original line number	Diff line number	Diff line
		@@ -174,6 +174,9 @@ const char Curl_printable_address(const Curl_addrinfo ip,
		* Curl_fetch_addr() fetches a 'Curl_dns_entry' already in the DNS cache.
		*
		* Returns the Curl_dns_entry entry pointer or NULL if not in the cache.
		*
		* The returned data MUST be "unlocked" with Curl_resolv_unlock() after
		* use, or we'll leak memory!
		*/
		struct Curl_dns_entry *
		Curl_fetch_addr(struct connectdata *conn,

lib/multi.c

+0 −7

Original line number	Diff line number	Diff line
		@@ -1112,13 +1112,9 @@ static CURLMcode multi_runsingle(struct Curl_multi *multi,
		struct connectdata *conn = data->easy_conn;

		/* check if we have the name resolved by now */
		if(data->share)
		Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);

		dns = Curl_fetch_addr(conn, conn->host.name, (int)conn->port);

		if(dns) {
		dns->inuse++; /* we use it! */
		#ifdef CURLRES_ASYNCH
		conn->async.dns = dns;
		conn->async.done = TRUE;
		@@ -1127,9 +1123,6 @@ static CURLMcode multi_runsingle(struct Curl_multi *multi,
		infof(data, "Hostname was found in DNS cache\n");
		}

		if(data->share)
		Curl_share_unlock(data, CURL_LOCK_DATA_DNS);

		if(!dns)
		result = Curl_resolver_is_resolved(data->easy_conn, &dns);