dns: Move gethostbyname to source file

Fix multiple definition of gethostbyname.

configure.py

@@ -398,6 +398,7 @@ scylla_core = (['database.cc',
                  'init.cc',
                  'repair/repair.cc',
                  'exceptions/exceptions.cc',
+                 'dns.cc',
                  ]
                 + [Antlr3Grammar('cql3/Cql.g')]
                 + [Thrift('interface/cassandra.thrift', 'Cassandra')]

dns.cc

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2015 ScyllaDB
+ */
+
+/*
+ * This file is part of Scylla.
+ *
+ * Scylla is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Scylla is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Scylla.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <boost/asio/ip/address_v4.hpp>
+#include <sys/socket.h>
+#include "core/sstring.hh"
+#include "core/future.hh"
+#include "dns.hh"
+
+
+namespace dns {
+
+future<hostent> gethostbyname(sstring name) {
+    hostent e = {name, {}, address_family::INET};
+    host_addr a;
+    if (name == "localhost") {
+        a.in.s_addr = static_cast<in_addr_t>(boost::asio::ip::address_v4::loopback().to_ulong());
+    } else {
+        a.in.s_addr = static_cast<in_addr_t>(boost::asio::ip::address_v4::from_string(name).to_ulong());
+    }
+    e.addresses.push_back(std::move(a));
+    return make_ready_future<hostent>(std::move(e));
+}
+
+}

dns.hh

@@ -48,15 +48,6 @@ struct hostent {
 
 // ATTENTION: this is stub only. It translates "localhost" into loopback address
 // otherwise it assumes that string is an IP address already
-future<hostent> gethostbyname(sstring name) {
-    hostent e = {name, {}, address_family::INET};
-    host_addr a;
-    if (name == "localhost") {
-        a.in.s_addr = static_cast<in_addr_t>(boost::asio::ip::address_v4::loopback().to_ulong());
-    } else {
-        a.in.s_addr = static_cast<in_addr_t>(boost::asio::ip::address_v4::from_string(name).to_ulong());
-    }
-    e.addresses.push_back(std::move(a));
-    return make_ready_future<hostent>(std::move(e));
-}
+future<hostent> gethostbyname(sstring name);
+
 }