Factor common code out of the test fake sources

* * *
More fake source refacoring

tests/fakes/source/close_after_hello.rb

@@ -7,43 +7,16 @@
 # After the disconnect, we reconnect to be sure that the destination
 # is still alive.
 
-
-require 'socket'
-require "timeout"
-require 'flexnbd/constants'
+require 'flexnbd/fake_source'
+include FlexNBD::FakeSource
 
 addr, port = *ARGV
 
-client_sock = nil
-begin
-  Timeout.timeout(2) do
-    client_sock = TCPSocket.open( addr, port )
-  end
-rescue Timeout::Error
-  $stderr.puts "Timed out connecting."
-  exit 1
-end
-
-begin
-  Timeout.timeout( FlexNBD::MS_HELLO_TIME_SECS ) do
-    fail "No hello." unless (hello = client_sock.read( 152 )) &&
-      hello.length==152
-  end
-rescue Timeout::Error
-  $stderr.puts "Timed out waiting for hello."
-  exit 1
-end
 
+client_sock = connect( addr, port, "Timed out connecting." )
+read_hello( client_sock )
 client_sock.close
-
 sleep(0.2)
-begin
-  Timeout.timeout(2) do
-    client_sock = TCPSocket.open( addr, port )
-  end
-rescue Timeout::Error
-  $stderr.puts "Timed out reconnecting."
-  exit 1
-end
+connect( addr, port, "Timed out reconnecting." )
 
 exit(0)