boot-v2.iso: initial commit

cmd/dkl-local-server/boot-iso.go

@@ -8,8 +8,12 @@ import (
 	"os"
 	"os/exec"
 	"path/filepath"
+	"strconv"
+
+	"github.com/cespare/xxhash"
 )
 
+// deprecated
 func buildBootISO(out io.Writer, ctx *renderContext) error {
 	tempDir, err := ioutil.TempDir("/tmp", "iso-")
 	if err != nil {
@@ -189,3 +193,159 @@ menuentry "Direktil" {
 
 	return cmd.Run()
 }
+
+func buildBootISOv2(out io.Writer, ctx *renderContext) (err error) {
+	tempDir, err := ioutil.TempDir("/tmp", "iso-v2-")
+	if err != nil {
+		return
+	}
+
+	defer os.RemoveAll(tempDir)
+
+	buildRes := func(build func(out io.Writer, ctx *renderContext) error, dst string) (err error) {
+		log.Printf("iso-v2: building %s", dst)
+
+		outPath := filepath.Join(tempDir, dst)
+
+		if err = os.MkdirAll(filepath.Dir(outPath), 0755); err != nil {
+			return err
+		}
+
+		out, err := os.Create(outPath)
+		if err != nil {
+			return err
+		}
+		defer out.Close()
+
+		err = build(out, ctx)
+		if err != nil {
+			return
+		}
+
+		return err
+	}
+
+	err = func() (err error) {
+		// grub
+
+		if err = os.MkdirAll(filepath.Join(tempDir, "grub"), 0755); err != nil {
+			return
+		}
+
+		// create a tag file
+		bootstrapBytes, _, err := ctx.BootstrapConfig()
+		if err != nil {
+			return
+		}
+
+		h := xxhash.New()
+		fmt.Fprintln(h, ctx.Host.Kernel)
+		h.Write(bootstrapBytes)
+
+		tag := "dkl-" + strconv.FormatUint(h.Sum64(), 32) + ".tag"
+
+		f, err := os.Create(filepath.Join(tempDir, tag))
+		if err != nil {
+			return
+		}
+		f.Write([]byte("direktil marker file\n"))
+		f.Close()
+
+		err = ioutil.WriteFile(filepath.Join(tempDir, "grub", "grub.cfg"), []byte(`
+search --set=root --file /`+tag+`
+
+insmod all_video
+set timeout=3
+
+menuentry "Direktil" {
+    linux  /vmlinuz `+ctx.CmdLine+`
+    initrd /initrd
+}
+`), 0644)
+		if err != nil {
+			return
+		}
+
+		coreImgPath := filepath.Join(tempDir, "grub", "core.img")
+		grubCfgPath := filepath.Join(tempDir, "grub", "grub.cfg")
+
+		cmd := exec.Command("grub-mkstandalone",
+			"--format=i386-pc",
+			"--output="+coreImgPath,
+			"--install-modules=linux normal iso9660 biosdisk memdisk search tar ls",
+			"--modules=linux normal iso9660 biosdisk search",
+			"--locales=",
+			"--fonts=",
+			"boot/grub/grub.cfg="+grubCfgPath,
+		)
+		cmd.Stdout = os.Stdout
+		cmd.Stderr = os.Stderr
+		if err := cmd.Run(); err != nil {
+			return err
+		}
+
+		defer os.Remove(coreImgPath)
+		defer os.Remove(grubCfgPath)
+
+		out, err := os.Create(filepath.Join(tempDir, "grub", "bios.img"))
+		if err != nil {
+			return err
+		}
+
+		defer out.Close()
+
+		b, err := ioutil.ReadFile("/usr/lib/grub/i386-pc/cdboot.img")
+		if err != nil {
+			return err
+		}
+
+		if _, err := out.Write(b); err != nil {
+			return err
+		}
+
+		b, err = ioutil.ReadFile(coreImgPath)
+		if err != nil {
+			return err
+		}
+
+		if _, err := out.Write(b); err != nil {
+			return err
+		}
+
+		return nil
+	}()
+	if err != nil {
+		return err
+	}
+
+	// kernel and initrd
+	buildRes(fetchKernel, "vmlinuz")
+	buildRes(buildInitrdV2, "initrd")
+
+	// build the ISO
+	mkisofs, err := exec.LookPath("genisoimage")
+	if err != nil {
+		mkisofs, err = exec.LookPath("mkisofs")
+	}
+	if err != nil {
+		return err
+	}
+
+	cmd := exec.Command(mkisofs,
+		"-quiet",
+		"-joliet",
+		"-joliet-long",
+		"-rock",
+		"-translation-table",
+		"-no-emul-boot",
+		"-boot-load-size", "4",
+		"-boot-info-table",
+		"-eltorito-boot", "grub/bios.img",
+		"-eltorito-catalog", "grub/boot.cat",
+		tempDir,
+	)
+	cmd.Stdout = out
+	cmd.Stderr = os.Stderr
+
+	return cmd.Run()
+}