builder/amazon/chroot: copyfiles support

builder/amazon/chroot/builder.go

@@ -26,6 +26,7 @@ type Config struct {
 
 	AttachedDevicePath string     `mapstructure:"attached_device_path"`
 	ChrootMounts       [][]string `mapstructure:"chroot_mounts"`
+	CopyFiles          []string   `mapstructure:"copy_files"`
 	DevicePath         string     `mapstructure:"device_path"`
 	MountCommand       string     `mapstructure:"mount_command"`
 	MountPath          string     `mapstructure:"mount_path"`
@@ -49,6 +50,10 @@ func (b *Builder) Prepare(raws ...interface{}) error {
 		b.config.ChrootMounts = make([][]string, 0)
 	}
 
+	if b.config.CopyFiles == nil {
+		b.config.CopyFiles = make([]string, 0)
+	}
+
 	if len(b.config.ChrootMounts) == 0 {
 		b.config.ChrootMounts = [][]string{
 			[]string{"proc", "proc", "/proc"},
@@ -59,6 +64,10 @@ func (b *Builder) Prepare(raws ...interface{}) error {
 		}
 	}
 
+	if len(b.config.CopyFiles) == 0 {
+		b.config.CopyFiles = []string{"/etc/resolv.conf"}
+	}
+
 	if b.config.DevicePath == "" {
 		b.config.DevicePath = "/dev/sdh"
 	}
@@ -127,6 +136,7 @@ func (b *Builder) Run(ui packer.Ui, hook packer.Hook, cache packer.Cache) (packe
 		&StepAttachVolume{},
 		&StepMountDevice{},
 		&StepMountExtra{},
+		&StepCopyFiles{},
 		&StepChrootProvision{},
 	}
 

builder/amazon/chroot/step_copy_files.go

@@ -0,0 +1,70 @@
+package chroot
+
+import (
+	"fmt"
+	"github.com/mitchellh/multistep"
+	"github.com/mitchellh/packer/packer"
+	"io"
+	"log"
+	"os"
+	"path/filepath"
+)
+
+// StepCopyFiles copies some files from the host into the chroot environment.
+type StepCopyFiles struct {
+	mounts []string
+}
+
+func (s *StepCopyFiles) Run(state map[string]interface{}) multistep.StepAction {
+	config := state["config"].(*Config)
+	mountPath := state["mount_path"].(string)
+	ui := state["ui"].(packer.Ui)
+
+	if len(config.CopyFiles) > 0 {
+		ui.Say("Copying files from host to chroot...")
+		for _, path := range config.CopyFiles {
+			ui.Message(path)
+			chrootPath := filepath.Join(mountPath, path)
+			log.Printf("Copying '%s' to '%s'", path, chrootPath)
+
+			if err := s.copySingle(chrootPath, path); err != nil {
+				err := fmt.Errorf("Error copying file: %s", err)
+				state["error"] = err
+				ui.Error(err.Error())
+				return multistep.ActionHalt
+			}
+		}
+	}
+
+	return multistep.ActionContinue
+}
+
+func (s *StepCopyFiles) Cleanup(state map[string]interface{}) {}
+
+func (s *StepCopyFiles) copySingle(dst, src string) error {
+	srcInfo, err := os.Stat(src)
+	if err != nil {
+		return err
+	}
+
+	srcF, err := os.Open(src)
+	if err != nil {
+		return err
+	}
+	defer srcF.Close()
+
+	dstF, err := os.Create(dst)
+	if err != nil {
+		return err
+	}
+
+	if _, err := io.Copy(dstF, srcF); err != nil {
+		return err
+	}
+
+	if err := os.Chmod(dst, srcInfo.Mode()); err != nil {
+		return err
+	}
+
+	return nil
+}