add grub support

Signed-off-by: Adphi <philippe.adrien.nousse@gmail.com>

grub.go

@@ -0,0 +1,105 @@
+// Copyright 2023 Linka Cloud  All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package d2vm
+
+import (
+	"context"
+	"fmt"
+	"os"
+	exec2 "os/exec"
+	"path/filepath"
+
+	"github.com/sirupsen/logrus"
+
+	"go.linka.cloud/d2vm/pkg/exec"
+)
+
+const grubCfg = `GRUB_DEFAULT=0
+GRUB_HIDDEN_TIMEOUT=0
+GRUB_HIDDEN_TIMEOUT_QUIET=true
+GRUB_TIMEOUT=0
+GRUB_CMDLINE_LINUX_DEFAULT="%s"
+GRUB_CMDLINE_LINUX=""
+GRUB_TERMINAL=console
+`
+
+type grub struct {
+	name string
+	c    Config
+	r    OSRelease
+}
+
+func (g grub) Setup(ctx context.Context, dev, root string, cmdline string) error {
+	logrus.Infof("setting up grub bootloader")
+	if err := os.WriteFile(filepath.Join(root, "etc", "default", "grub"), []byte(fmt.Sprintf(grubCfg, cmdline)), perm); err != nil {
+		return err
+	}
+	if err := os.MkdirAll(filepath.Join(root, "boot", g.name), os.ModePerm); err != nil {
+		return err
+	}
+	mounts := []string{"dev", "proc", "sys"}
+	var unmounts []string
+	defer func() {
+		for _, v := range unmounts {
+			if err := exec.Run(ctx, "umount", filepath.Join(root, v)); err != nil {
+				logrus.Errorf("failed to unmount /%s: %s", v, err)
+			}
+		}
+	}()
+	for _, v := range mounts {
+		if err := exec.Run(ctx, "mount", "-o", "bind", "/"+v, filepath.Join(root, v)); err != nil {
+			return err
+		}
+		unmounts = append(unmounts, v)
+	}
+
+	if err := exec.Run(ctx, "chroot", root, g.name+"-install", "--target=i386-pc", "--boot-directory", "/boot", dev); err != nil {
+		return err
+	}
+	if err := exec.Run(ctx, "chroot", root, g.name+"-mkconfig", "-o", "/boot/"+g.name+"/grub.cfg"); err != nil {
+		return err
+	}
+	return nil
+}
+
+type grubBootloaderProvider struct {
+	config Config
+}
+
+func (g grubBootloaderProvider) New(c Config, r OSRelease) (Bootloader, error) {
+	name := "grub"
+	if r.ID == "centos" {
+		name = "grub2"
+	}
+	if _, err := exec2.LookPath("grub-install"); err != nil {
+		return nil, err
+	}
+	if _, err := exec2.LookPath("grub-mkconfig"); err != nil {
+		return nil, err
+	}
+	return grub{
+		name: name,
+		c:    c,
+		r:    r,
+	}, nil
+}
+
+func (g grubBootloaderProvider) Name() string {
+	return "grub"
+}
+
+func init() {
+	RegisterBootloaderProvider(grubBootloaderProvider{})
+}