Setup kernel support

internal/pkg/kernel/kernel.go

@@ -0,0 +1,61 @@
+package kernel
+
+import (
+	"fmt"
+	"github.com/hpcng/warewulf/internal/pkg/config"
+	"github.com/hpcng/warewulf/internal/pkg/errors"
+	"github.com/hpcng/warewulf/internal/pkg/util"
+	"github.com/hpcng/warewulf/internal/pkg/wwlog"
+	"os"
+	"os/exec"
+	"path"
+)
+
+func Build(kernelVersion string) error {
+	config := config.New()
+
+	kernelImage := "/boot/vmlinuz-" + kernelVersion
+	kernelDrivers := "/lib/modules/" + kernelVersion
+	kernelDestination := config.KernelImage(kernelVersion)
+	driversDestination := config.KmodsImage(kernelVersion)
+
+	// Create the destination paths just in case it doesn't exist
+	os.MkdirAll(path.Dir(kernelDestination), 0755)
+	os.MkdirAll(path.Dir(driversDestination), 0755)
+
+	if util.IsFile(kernelImage) == false {
+		return errors.New("Could not locate kernel image: " + kernelImage)
+	}
+
+	if util.IsDir(kernelDrivers) == false {
+		return errors.New("Could not locate kernel drivers: " + kernelDrivers)
+	}
+
+	if _, err := os.Stat(kernelImage); err == nil {
+		if util.PathIsNewer(kernelImage, kernelDestination) {
+			wwlog.Printf(wwlog.INFO, "%-45s: Skipping, kernel is current\n", "vmlinuz-"+kernelVersion)
+		} else {
+			err := util.CopyFile(kernelImage, kernelDestination)
+			if err != nil {
+				return err
+			}
+			wwlog.Printf(wwlog.INFO, "%-45s: Done\n", "vmlinuz-"+kernelVersion)
+		}
+	}
+
+	if _, err := os.Stat(kernelDrivers); err == nil {
+		if util.PathIsNewer(kernelDrivers, driversDestination) {
+			wwlog.Printf(wwlog.INFO, "%-45s: Skipping, drivers are current\n", "kmods-"+kernelVersion+".img")
+
+		} else {
+			cmd := fmt.Sprintf("cd /; find .%s | cpio --quiet -o -H newc -F \"%s\"", kernelDrivers, driversDestination)
+			err := exec.Command("/bin/sh", "-c", cmd).Run()
+			if err != nil {
+				return err
+			}
+			wwlog.Printf(wwlog.INFO, "%-45s: Done\n", "kmods-"+kernelVersion+".img")
+		}
+	}
+
+	return nil
+}