parallels/vmware: don't wait for shutdown command.

Resolves #4134

replaces/ closes #4379

Leaving Hyper-V builder alone for now until we can get a case that reproduces.

builder/parallels/common/step_shutdown.go

@@ -1,6 +1,7 @@
 package common
 
 import (
+	"bytes"
 	"errors"
 	"fmt"
 	"log"
@@ -36,9 +37,15 @@ func (s *StepShutdown) Run(state multistep.StateBag) multistep.StepAction {
 	if s.Command != "" {
 		ui.Say("Gracefully halting virtual machine...")
 		log.Printf("Executing shutdown command: %s", s.Command)
-		cmd := &packer.RemoteCmd{Command: s.Command}
-		if err := cmd.StartWithUi(comm, ui); err != nil {
-			err = fmt.Errorf("Failed to send shutdown command: %s", err)
+
+		var stdout, stderr bytes.Buffer
+		cmd := &packer.RemoteCmd{
+			Command: s.Command,
+			Stdout:  &stdout,
+			Stderr:  &stderr,
+		}
+		if err := comm.Start(cmd); err != nil {
+			err := fmt.Errorf("Failed to send shutdown command: %s", err)
 			state.Put("error", err)
 			ui.Error(err.Error())
 			return multistep.ActionHalt
@@ -55,6 +62,8 @@ func (s *StepShutdown) Run(state multistep.StateBag) multistep.StepAction {
 
 			select {
 			case <-shutdownTimer:
+				log.Printf("Shutdown stdout: %s", stdout.String())
+				log.Printf("Shutdown stderr: %s", stderr.String())
 				err := errors.New("Timeout while waiting for machine to shut down.")
 				state.Put("error", err)
 				ui.Error(err.Error())

builder/vmware/common/step_shutdown.go

@@ -57,14 +57,6 @@ func (s *StepShutdown) Run(state multistep.StateBag) multistep.StepAction {
 			return multistep.ActionHalt
 		}
 
-		// Wait for the command to run so we can print std{err,out}
-		// We don't care if the command errored, since we'll notice
-		// if the vm didn't shut down.
-		cmd.Wait()
-
-		log.Printf("Shutdown stdout: %s", stdout.String())
-		log.Printf("Shutdown stderr: %s", stderr.String())
-
 		// Wait for the machine to actually shut down
 		log.Printf("Waiting max %s for shutdown to complete", s.Timeout)
 		shutdownTimer := time.After(s.Timeout)
@@ -76,6 +68,8 @@ func (s *StepShutdown) Run(state multistep.StateBag) multistep.StepAction {
 
 			select {
 			case <-shutdownTimer:
+				log.Printf("Shutdown stdout: %s", stdout.String())
+				log.Printf("Shutdown stderr: %s", stderr.String())
 				err := errors.New("Timeout while waiting for machine to shut down.")
 				state.Put("error", err)
 				ui.Error(err.Error())

packer/communicator.go

@@ -9,7 +9,7 @@ import (
 	"github.com/mitchellh/iochan"
 )
 
-// CmdDisconnect is a sentry value to indicate a RemoteCmd
+// CmdDisconnect is a sentinel value to indicate a RemoteCmd
 // exited because the remote side disconnected us.
 const CmdDisconnect int = 2300218