From 09b5a99816a24a12f769f61db5f7eafd4bc32795 Mon Sep 17 00:00:00 2001 From: Michael Wallner Date: Wed, 20 Aug 2014 23:31:53 +0200 Subject: resolve: cache lookup for async resolvers While waiting for a host resolve, check if the host cache may have gotten the name already (by someone else), for when the same name is resolved by several simultanoues requests. The resolver thread occasionally gets stuck in getaddrinfo() when the DNS or anything else is crappy or slow, so when a host is found in the DNS cache, leave the thread alone and let itself cleanup the mess. --- lib/multi.c | 26 +++++++++++++++++++++++++- 1 file changed, 25 insertions(+), 1 deletion(-) (limited to 'lib/multi.c') diff --git a/lib/multi.c b/lib/multi.c index 1e5b3c8df..20fc372fa 100644 --- a/lib/multi.c +++ b/lib/multi.c @@ -30,6 +30,7 @@ #include "connect.h" #include "progress.h" #include "easyif.h" +#include "share.h" #include "multiif.h" #include "sendf.h" #include "timeval.h" @@ -1084,9 +1085,32 @@ static CURLMcode multi_runsingle(struct Curl_multi *multi, /* awaiting an asynch name resolve to complete */ { struct Curl_dns_entry *dns = NULL; + struct connectdata *conn = data->easy_conn; + int stale; /* check if we have the name resolved by now */ - data->result = Curl_resolver_is_resolved(data->easy_conn, &dns); + 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, &stale); + + if(dns) { + dns->inuse++; /* we use it! */ +#ifdef CURLRES_ASYNCH + conn->async.dns = dns; + conn->async.done = TRUE; +#endif + data->result = CURLRESOLV_RESOLVED; + infof(data, "Hostname was found in DNS cache\n"); + } + if(stale) + infof(data, "Hostname in DNS cache was stale, zapped\n"); + + if(data->share) + Curl_share_unlock(data, CURL_LOCK_DATA_DNS); + + if(!dns) + data->result = Curl_resolver_is_resolved(data->easy_conn, &dns); /* Update sockets here, because the socket(s) may have been closed and the application thus needs to be told, even if it -- cgit v1.2.3