1 files changed, 160 insertions, 0 deletions
diff --git a/pkg/machine/fcos.go b/pkg/machine/fcos.go
new file mode 100644
index 000000000..0c6a2485e
--- /dev/null
+++ b/pkg/machine/fcos.go
@@ -0,0 +1,160 @@
+package machine
+
+import (
+	"crypto/sha256"
+	"io"
+	"io/ioutil"
+	url2 "net/url"
+	"os"
+	"path/filepath"
+	"runtime"
+	"strings"
+
+	"github.com/containers/storage/pkg/archive"
+	digest "github.com/opencontainers/go-digest"
+	"github.com/sirupsen/logrus"
+)
+
+// These should eventually be moved into machine/qemu as
+// they are specific to running qemu
+var (
+	artifact string = "qemu"
+	Format   string = "qcow2.xz"
+)
+
+type FcosDownload struct {
+	Download
+}
+
+func NewFcosDownloader(vmType, vmName string) (DistributionDownload, error) {
+	info, err := getFCOSDownload()
+	if err != nil {
+		return nil, err
+	}
+	urlSplit := strings.Split(info.Location, "/")
+	imageName := urlSplit[len(urlSplit)-1]
+	url, err := url2.Parse(info.Location)
+	if err != nil {
+		return nil, err
+	}
+
+	dataDir, err := GetDataDir(vmType)
+	if err != nil {
+		return nil, err
+	}
+
+	fcd := FcosDownload{
+		Download: Download{
+			Arch:      getFcosArch(),
+			Artifact:  artifact,
+			Format:    Format,
+			ImageName: imageName,
+			LocalPath: filepath.Join(dataDir, imageName),
+			Sha256sum: info.Sha256Sum,
+			URL:       url,
+			VMName:    vmName,
+		},
+	}
+	fcd.Download.LocalUncompressedFile = fcd.getLocalUncompressedName()
+	return fcd, nil
+}
+
+func (f FcosDownload) getLocalUncompressedName() string {
+	uncompressedFilename := filepath.Join(filepath.Dir(f.LocalPath), f.VMName+"_"+f.ImageName)
+	return strings.TrimSuffix(uncompressedFilename, ".xz")
+}
+
+func (f FcosDownload) DownloadImage() error {
+	// check if the latest image is already present
+	ok, err := UpdateAvailable(&f.Download)
+	if err != nil {
+		return err
+	}
+	if !ok {
+		if err := DownloadVMImage(f.URL, f.LocalPath); err != nil {
+			return err
+		}
+	}
+	uncompressedFileWriter, err := os.OpenFile(f.getLocalUncompressedName(), os.O_CREATE|os.O_RDWR, 0600)
+	if err != nil {
+		return err
+	}
+	sourceFile, err := ioutil.ReadFile(f.LocalPath)
+	if err != nil {
+		return err
+	}
+	compressionType := archive.DetectCompression(sourceFile)
+	f.CompressionType = compressionType.Extension()
+
+	switch f.CompressionType {
+	case "tar.xz":
+		return decompressXZ(f.LocalPath, uncompressedFileWriter)
+	default:
+		// File seems to be uncompressed, make a copy
+		if err := copyFile(f.LocalPath, uncompressedFileWriter); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func copyFile(src string, dest *os.File) error {
+	source, err := os.Open(src)
+	if err != nil {
+		return err
+	}
+	defer func() {
+		if err := source.Close(); err != nil {
+			logrus.Error(err)
+		}
+	}()
+	_, err = io.Copy(dest, source)
+	return err
+}
+
+func (f FcosDownload) Get() *Download {
+	return &f.Download
+}
+
+type fcosDownloadInfo struct {
+	CompressionType string
+	Location        string
+	Release         string
+	Sha256Sum       string
+}
+
+func UpdateAvailable(d *Download) (bool, error) {
+	//	 check the sha of the local image if it exists
+	//  get the sha of the remote image
+	// == dont bother to pull
+	files, err := ioutil.ReadDir(filepath.Dir(d.LocalPath))
+	if err != nil {
+		return false, err
+	}
+	for _, file := range files {
+		if filepath.Base(d.LocalPath) == file.Name() {
+			b, err := ioutil.ReadFile(d.LocalPath)
+			if err != nil {
+				return false, err
+			}
+			s := sha256.Sum256(b)
+			sum := digest.NewDigestFromBytes(digest.SHA256, s[:])
+			if sum.Encoded() == d.Sha256sum {
+				return true, nil
+			}
+		}
+	}
+	return false, nil
+}
+
+func getFcosArch() string {
+	var arch string
+	// TODO fill in more architectures
+	switch runtime.GOARCH {
+	case "arm64":
+		arch = "aarch64"
+	default:
+		arch = "x86_64"
+	}
+	return arch
+}