Call getaddrinfo from Ruby

`getaddrinfo` is notorious for not having a timeout, which can make
it hang for a very long time. Since Trilogy releases the GVL before
calling it, that can cause the whole VM to be unresponsive and no
longer respond to ctrl+c etc.

In 3.3.0, Ruby is now doing name resolution from a background thread,
making `Socket.getaddrinfo` interruptible. So by doing the name resolution
on the Ruby side, we should avoid such scenarios.

contrib/ruby/lib/trilogy.rb

@@ -8,10 +8,23 @@
 
 class Trilogy
   def initialize(options = {})
+    options = options.dup
     options[:port] = options[:port].to_i if options[:port]
     mysql_encoding = options[:encoding] || "utf8mb4"
     encoding = Trilogy::Encoding.find(mysql_encoding)
     charset = Trilogy::Encoding.charset(mysql_encoding)
+
+    if options[:host]
+      addrs = begin
+        Socket.getaddrinfo(options[:host], options[:port], :PF_UNSPEC, :SOCK_STREAM)
+      rescue SocketError => error
+        raise Trilogy::BaseConnectionError, "Couldn't resolve host: #{options[:host].inspect}"
+      end
+
+      addrs.sort_by!(&:first) # Priority to IPv4
+      options[:host] = addrs.first[3]
+    end
+
     @connection_options = options
     @connected_host = nil
 

contrib/ruby/test/client_test.rb

@@ -953,7 +953,7 @@ def test_connection_invalid_dns
     ex = assert_raises Trilogy::ConnectionError do
       new_tcp_client(host: "mysql.invalid", port: 3306)
     end
-    assert_equal "trilogy_connect - unable to connect to mysql.invalid:3306: TRILOGY_DNS_ERROR", ex.message
+    assert_includes ex.message, %{Couldn't resolve host: "mysql.invalid"}
   end
 
   def test_memsize