connect failure scenarios

tests/fakes/dest/close_after_hello.rb

@@ -0,0 +1,47 @@
+#!/usr/bin/env ruby
+
+# Wait for a sender connection, send a correct hello, then disconnect.
+# Simulate a server which crashes after sending the hello.  We then
+# reopen the server socket to check that the sender retries: since the
+# command-line has gone away, and can't feed an error back to the
+# user, we have to keep trying.
+
+addr, port = *ARGV
+
+require 'socket'
+require 'timeout'
+
+sock = TCPServer.new( addr, port )
+client_sock = nil
+
+begin
+  Timeout.timeout(2) do
+    client_sock = sock.accept
+  end
+rescue Timeout::Error
+  $stderr.puts "Timed out waiting for a connection"
+  exit 1
+end
+
+
+client_sock.write( "NBDMAGIC" )
+client_sock.write( "\x00\x00\x42\x02\x81\x86\x12\x53" )
+client_sock.write( "\x00\x00\x00\x00\x00\x00\x10\x00" )
+client_sock.write( "\x00" * 128 )
+
+client_sock.close
+
+new_sock = nil
+begin
+  Timeout.timeout(60) do
+    new_sock = sock.accept
+  end
+rescue Timeout::Error
+  $stderr.puts "Timed out waiting for a reconnection"
+  exit 1
+end
+
+new_sock.close
+sock.close
+
+exit 0