more fixes from errcheck

builder/profitbricks/step_create_server.go

@@ -72,7 +72,11 @@ func (s *stepCreateServer) Run(state multistep.StateBag) multistep.StepAction {
 	if datacenter.StatusCode > 299 {
 		if datacenter.StatusCode > 299 {
 			var restError RestError
-			json.Unmarshal([]byte(datacenter.Response), &restError)
+			err := json.Unmarshal([]byte(datacenter.Response), &restError)
+			if err != nil {
+				ui.Error(fmt.Sprintf("Error decoding json response: %s", err.Error()))
+				return multistep.ActionHalt
+			}
 			if len(restError.Messages) > 0 {
 				ui.Error(restError.Messages[0].Message)
 			} else {
@@ -147,9 +151,11 @@ func (s *stepCreateServer) Cleanup(state multistep.StateBag) {
 
 	if dcId, ok := state.GetOk("datacenter_id"); ok {
 		resp := profitbricks.DeleteDatacenter(dcId.(string))
-		s.checkForErrors(resp)
+		if err := s.checkForErrors(resp); err != nil {
-		err := s.waitTillProvisioned(resp.Headers.Get("Location"), *c)
+			ui.Error(fmt.Sprintf(
-		if err != nil {
+				"Error deleting Virtual Data Center. Please destroy it manually: %s", err))
+		}
+		if err := s.waitTillProvisioned(resp.Headers.Get("Location"), *c); err != nil {
 			ui.Error(fmt.Sprintf(
 				"Error deleting Virtual Data Center. Please destroy it manually: %s", err))
 		}

builder/profitbricks/step_take_snapshot.go

@@ -28,7 +28,10 @@ func (s *stepTakeSnapshot) Run(state multistep.StateBag) multistep.StepAction {
 
 	if snapshot.StatusCode > 299 {
 		var restError RestError
-		json.Unmarshal([]byte(snapshot.Response), &restError)
+		if err := json.Unmarshal([]byte(snapshot.Response), &restError); err != nil {
+			ui.Error(err.Error())
+			return multistep.ActionHalt
+		}
 		if len(restError.Messages) > 0 {
 			ui.Error(restError.Messages[0].Message)
 		} else {

post-processor/amazon-import/post-processor.go

@@ -239,7 +239,7 @@ func (p *PostProcessor) PostProcess(ui packer.Ui, artifact packer.Artifact) (pac
 			return nil, false, fmt.Errorf("Error waiting for AMI (%s): %s", *resp.ImageId, err)
 		}
 
-		ec2conn.DeregisterImage(&ec2.DeregisterImageInput{
+		_, err = ec2conn.DeregisterImage(&ec2.DeregisterImageInput{
 			ImageId: &createdami,
 		})
 

provisioner/ansible/provisioner.go

@@ -355,7 +355,9 @@ func (p *Provisioner) executeAnsible(ui packer.Ui, comm packer.Communicator, pri
 	go repeat(stderr)
 
 	log.Printf("Executing Ansible: %s", strings.Join(cmd.Args, " "))
-	cmd.Start()
+	if err := cmd.Start(); err != nil {
+		return err
+	}
 	wg.Wait()
 	err = cmd.Wait()
 	if err != nil {

provisioner/ansible/scp.go

@@ -104,8 +104,7 @@ func (state *scpDownloadState) FileProtocol(path string, info os.FileInfo, in *b
 	size := info.Size()
 	perms := fmt.Sprintf("C%04o", info.Mode().Perm())
 	fmt.Fprintln(out, perms, size, info.Name())
-	err := scpResponse(in)
+	if err := scpResponse(in); err != nil {
-	if err != nil {
 		return err
 	}
 
@@ -194,8 +193,7 @@ func (state *scpUploadState) FileProtocol(in *bufio.Reader, out io.Writer) error
 		return err
 	}
 
-	err = scpResponse(in)
+	if err := scpResponse(in); err != nil {
-	if err != nil {
 		return err
 	}
 
@@ -260,7 +258,9 @@ type scpDownloadState struct {
 func (state *scpDownloadState) Protocol(in *bufio.Reader, out io.Writer) error {
 	r := bufio.NewReader(in)
 	// read the byte sent by the other side to start the transfer
-	scpResponse(r)
+	if err := scpResponse(r); err != nil {
+		return err
+	}
 
 	return filepath.Walk(state.srcRoot, func(path string, info os.FileInfo, err error) error {
 		if err != nil {