chore: bootloader abtraction

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

config.go

@@ -0,0 +1,89 @@
+// 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 (
+	"fmt"
+	"strings"
+)
+
+var (
+	configUbuntu = Config{
+		Kernel: "/boot/vmlinuz",
+		Initrd: "/boot/initrd.img",
+	}
+	configDebian = Config{
+		Kernel: "/vmlinuz",
+		Initrd: "/initrd.img",
+	}
+	configAlpine = Config{
+		Kernel: "/boot/vmlinuz-virt",
+		Initrd: "/boot/initramfs-virt",
+	}
+	configCentOS = Config{
+		Kernel: "/boot/vmlinuz",
+		Initrd: "/boot/initrd.img",
+	}
+)
+
+type Root interface {
+	String() string
+}
+
+type RootUUID string
+
+func (r RootUUID) String() string {
+	return "UUID=" + string(r)
+}
+
+type RootPath string
+
+func (r RootPath) String() string {
+	return string(r)
+}
+
+type Config struct {
+	Kernel string
+	Initrd string
+}
+
+func (c Config) Cmdline(root Root, args ...string) string {
+	var r string
+	if root != nil {
+		r = fmt.Sprintf("root=%s", root.String())
+	}
+	return fmt.Sprintf("ro initrd=%s %s net.ifnames=0 rootfstype=ext4 console=tty0 console=ttyS0,115200n8 %s", c.Initrd, r, strings.Join(args, " "))
+}
+
+func (r OSRelease) Config() (Config, error) {
+	switch r.ID {
+	case ReleaseUbuntu:
+		if r.VersionID < "20.04" {
+			return configDebian, nil
+		}
+		return configUbuntu, nil
+	case ReleaseDebian:
+		return configDebian, nil
+	case ReleaseKali:
+		return configDebian, nil
+	case ReleaseAlpine:
+		return configAlpine, nil
+	case ReleaseCentOS:
+		return configCentOS, nil
+	default:
+		return Config{}, fmt.Errorf("%s: distribution not supported", r.ID)
+
+	}
+}