1 files changed, 61 insertions, 0 deletions
diff --git a/features/support/helpers/exec_helper.rb b/features/support/helpers/exec_helper.rb
new file mode 100644
index 00000000..b0d3a9cd
--- /dev/null
+++ b/features/support/helpers/exec_helper.rb
@@ -0,0 +1,61 @@
+require 'json'
+require 'socket'
+
+class VMCommand
+
+  attr_reader :cmd, :returncode, :stdout, :stderr
+
+  def initialize(vm, cmd, options = {})
+    @cmd = cmd
+    @returncode, @stdout, @stderr = VMCommand.execute(vm, cmd, options)
+  end
+
+  def VMCommand.wait_until_remote_shell_is_up(vm, timeout = 30)
+    begin
+      Timeout::timeout(timeout) do
+        VMCommand.execute(vm, "true", { :user => "root", :spawn => false })
+      end
+    rescue Timeout::Error
+      raise "Remote shell seems to be down"
+    end
+  end
+
+  # The parameter `cmd` cannot contain newlines. Separate multiple
+  # commands using ";" instead.
+  # If `:spawn` is false the server will block until it has finished
+  # executing `cmd`. If it's true the server won't block, and the
+  # response will always be [0, "", ""] (only used as an
+  # ACK). execute() will always block until a response is received,
+  # though. Spawning is useful when starting processes in the
+  # background (or running scripts that does the same) like the
+  # vidalia-wrapper, or any application we want to interact with.
+  def VMCommand.execute(vm, cmd, options = {})
+    options[:user] ||= "root"
+    options[:spawn] ||= false
+    type = options[:spawn] ? "spawn" : "call"
+    socket = TCPSocket.new("127.0.0.1", vm.get_remote_shell_port)
+    STDERR.puts "#{type}ing as #{options[:user]}: #{cmd}" if $debug
+    begin
+      socket.puts(JSON.dump([type, options[:user], cmd]))
+      s = socket.readline(sep = "\0").chomp("\0")
+    ensure
+      socket.close
+    end
+    STDERR.puts "#{type} returned: #{s}" if $debug
+    begin
+      return JSON.load(s)
+    rescue JSON::ParserError
+      # The server often returns something unparsable for the very
+      # first execute() command issued after a VM start/restore
+      # (generally from wait_until_remote_shell_is_up()) presumably
+      # because the TCP -> serial link isn't properly setup yet. All
+      # will be well after that initial hickup, so we just retry.
+      return VMCommand.execute(vm, cmd, options)
+    end
+  end
+
+  def success?
+    return @returncode == 0
+  end
+
+end