virtigolib/libvirtxml.go

// Copyright 2024 WIT.COM Inc Licensed GPL 3.0

package virtigolib

import (
	"encoding/xml"
	"fmt"
	"os"
	"path/filepath"
	"reflect"
	"strings"

	"go.wit.com/log"
	"libvirt.org/go/libvirtxml"
)

/*
func makeStandardXml(hostname string) *libvirtxml.Domain {
	log.Info("create new xml file for:", hostname)
	domcfg := &libvirtxml.Domain{}

	addDefaultXml(domcfg, "standard.x86")
	addDefaultXml(domcfg, "memory")
	addDefaultXml(domcfg, "network")
	addDefaultXml(domcfg, "spice")
	addDefaultXml(domcfg, "qcow")

	return domcfg
}
*/

func writeoutXml(domcfg *libvirtxml.Domain, filename string) error {
	xmldoc, err := domcfg.Marshal()

	if err != nil {
		fmt.Println("can't make xml file error:\n", err)
		return err
	}

	outfile := "/tmp/" + filename + ".xml"
	regfile, err := os.OpenFile(outfile, os.O_RDWR|os.O_CREATE, 0666)
	if err != nil {
		return err
	}
	fmt.Fprintln(regfile, xmldoc)

	log.Info("File is in", outfile)
	regfile.Close()
	return nil
}

func setDiskFilename(domcfg *libvirtxml.Domain, filename string) {
	for i, x := range domcfg.Devices.Disks {
		// Create a new DomainDiskSourceFile struct
		newSource := &libvirtxml.DomainDiskSourceFile{
			File: filename, // Set the file name here
		}

		// Assign it to the disk's source
		domcfg.Devices.Disks[i].Source.File = newSource

		// fmt.Printf("Disk Source %s\n", name)
		fmt.Printf("Disk Device %s\n", x.Source.File)
	}
}

func ReadXml(filename string) (*libvirtxml.Domain, error) {
	log.Verbose("parse xml file:", filename)

	hostname := filepath.Base(filename)
	hostname = strings.TrimSuffix(hostname, ".xml")

	pfile, err := os.ReadFile(filename)
	if err != nil {
		log.Println("ERROR:", err)
		return nil, err
	}

	domcfg := &libvirtxml.Domain{}

	err = domcfg.Unmarshal(string(pfile))
	if err != nil {
		log.Info("Marshal failed on file", filename, err)
		return nil, err
	}

	if domcfg.Name != hostname {
		log.Info("ERROR: filename:", filename)
		log.Info("ERROR: domcfg.Name != name", domcfg.Name, hostname)
		log.Info("ERROR: xml filenames must match the xml name")
		os.Exit(-1)
	}

	return domcfg, nil
}

func mergeXml(domcfg *libvirtxml.Domain, filename string) error {
	log.Info("merge xml file:", filename)

	pfile, err := os.ReadFile(filename)
	if err != nil {
		log.Println("ERROR:", err)
		return err
	}

	err = domcfg.Unmarshal(string(pfile))
	if err != nil {
		log.Info("Marshal failed on file", filename)
		return err
	}
	return nil
}

func setSimpleDisk(domcfg *libvirtxml.Domain, filename string) {
	// Clear out the existing disks (if any)
	domcfg.Devices.Disks = nil

	// Define a new disk with "mynew.qcow2"
	newDisk := libvirtxml.DomainDisk{
		Device: "disk",
		Driver: &libvirtxml.DomainDiskDriver{
			Name: "qemu",
			Type: "qcow2",
		},
		Source: &libvirtxml.DomainDiskSource{
			File: &libvirtxml.DomainDiskSourceFile{
				File: filename,
			},
		},
		Target: &libvirtxml.DomainDiskTarget{
			Dev: "vda",
			Bus: "virtio",
		},
	}

	// Add the new disk to the domain configuration
	domcfg.Devices.Disks = append(domcfg.Devices.Disks, newDisk)
}

func getMacs(domcfg *libvirtxml.Domain) []string {
	var macs []string
	// Iterate over the network interfaces and print the MAC addresses
	for _, iface := range domcfg.Devices.Interfaces {
		if iface.MAC != nil {
			// iface.MAC.Address = "aa:bb:aa:bb:aa:ff"
			fmt.Printf("MAC Address: %+v\n", iface.MAC)
			// fmt.Printf("Interface: %s, MAC Address: %s\n", iface.Target.Dev, iface.MAC.Address)
			macs = append(macs, iface.MAC.Address)
		} else {
			fmt.Printf("Interface: %s, MAC Address: not available\n", iface.Target.Dev)
		}
	}
	return macs
}

// removes all the ethernet interfaces
func clearEthernet(domcfg *libvirtxml.Domain) {
	// Clear out the existing disks (if any)
	domcfg.Devices.Interfaces = nil
}

// add a new ethernet interface with mac assigned to bridge name
func addEthernetBridge(domcfg *libvirtxml.Domain, mac string, brname string) {
	// Define a new disk with "mynew.qcow2"
	// type DomainInterfaceType string

	var ib *libvirtxml.DomainInterfaceSourceBridge
	ib = new(libvirtxml.DomainInterfaceSourceBridge)
	ib.Bridge = brname

	newNet := libvirtxml.DomainInterface{
		MAC: &libvirtxml.DomainInterfaceMAC{
			Address: mac,
		},
		Source: &libvirtxml.DomainInterfaceSource{
			Bridge: ib,
		},
		Model: &libvirtxml.DomainInterfaceModel{
			Type: "virtio",
		},
		/* this is for raw tap. use this for people who don't
		   who don't have bridge groups or proper cluster backend networking
		   literally leaving this blank makes the interface 'tap0'
		*/
		// Target: &libvirtxml.DomainInterfaceTarget{
		// },
	}

	// Add the new disk to the domain configuration
	domcfg.Devices.Interfaces = append(domcfg.Devices.Interfaces, newNet)
}

// makes an ethernet interface with qemu on dom0 as 'tapXXX'
// doesn't require a bridge group or any changes to dom0 networking (probably)
func addEthernetTap(domcfg *libvirtxml.Domain, mac string) {
	newNet := libvirtxml.DomainInterface{
		MAC: &libvirtxml.DomainInterfaceMAC{
			Address: mac,
		},
		/* this is for raw tap. use this for people who don't
		   who don't have bridge groups or proper cluster backend networking
		   literally leaving this blank makes the interface 'tap0'
		*/
		Target: &libvirtxml.DomainInterfaceTarget{},
	}

	// Add the new disk to the domain configuration
	domcfg.Devices.Interfaces = append(domcfg.Devices.Interfaces, newNet)
}

func setRandomMacs(domcfg *libvirtxml.Domain) {
	for i, x := range domcfg.Devices.Interfaces {
		// Create a new DomainDiskInterfaces struct
		newMac := &libvirtxml.DomainInterfaceMAC{
			Address: "aa:bb:cc:dd:ee:ff", // make sure this is unique
		}

		// Assign it to the disk's source
		domcfg.Devices.Interfaces[i].MAC = newMac

		// fmt.Printf("Disk Source %s\n", name)
		// fmt.Printf("mac addr %+v\n", x.MAC)
		fmt.Printf("mac addr %s\n", x.MAC.Address)
	}
}

// this tries the final zero'ing out of the XML
// todo: if this fails, put the remaining XML in the protobuf file?
func finalEmptyCheck(domcfg *libvirtxml.Domain) (string, error) {
	// dumpLibvirtxmlDomainNames()
	if libvirtxmlDomainDevicesEmpty(*domcfg.Devices) {
		// fmt.Println("Domain Devices are empty")
		domcfg.Devices = nil
	} else {
		return warnUserOfNonStandardXML(domcfg)
	}

	if libvirtxmlDomainEmpty(*domcfg) {
		domcfg = nil
		return warnUserOfNonStandardXML(domcfg)
	}

	final, err := warnUserOfNonStandardXML(domcfg)
	if err != nil {
		fmt.Printf("todo: improve this libvirtXML parsing. %v\n", err)
		os.Exit(-1)
	}
	return final, nil
}

func xmlAny(a any) (string, error) {
	updatedXML, err := xml.MarshalIndent(a, "", "  ")
	if err != nil {
		fmt.Printf("Failed to marshal updated XML: %v\n", err)
		return "", err
	}
	final := string(updatedXML)
	if final == "" {
		// everything seems to have been parsed pretty standard
		return "", nil
	}
	log.Info("Non-Standard XML Start")
	fmt.Println(final)
	log.Info("Non-Standard XML End")
	return final, nil
}

func warnUserOfNonStandardXML(domcfg *libvirtxml.Domain) (string, error) {
	updatedXML, err := xml.MarshalIndent(domcfg, "", "  ")
	if err != nil {
		fmt.Printf("Failed to marshal updated XML: %v\n", err)
		return "", err
	}
	final := string(updatedXML)
	if final == "" {
		// everything seems to have been parsed pretty standard
		return "", nil
	}
	log.Info("Non-Standard XML Start")
	fmt.Println(string(updatedXML))
	log.Info("Non-Standard XML End")
	log.Info("")
	log.Info("This XML must be removed by hand. Put this in the protobuf?")
	return string(updatedXML), nil
}

// dump out all the fields in libvirtxml.DomainDeviceList
func DumpLibvirtxmlDomainNames() {
	var domain libvirtxml.Domain
	t := reflect.TypeOf(domain)

	fmt.Println("Fields in libvirtxml.Domain:")
	for i := 0; i < t.NumField(); i++ {
		field := t.Field(i)
		fmt.Println("Domain:", field.Name)
	}

	var device libvirtxml.DomainDeviceList
	t = reflect.TypeOf(device)

	fmt.Println("Fields in libvirtxml.DomainDeviceList:")
	for i := 0; i < t.NumField(); i++ {
		field := t.Field(i)
		fmt.Println("DomainDeviceList:", field.Name)
	}

	var iface libvirtxml.DomainInterface
	t = reflect.TypeOf(iface)

	fmt.Println("Fields in libvirtxml.DomainInterface:")
	for i := 0; i < t.NumField(); i++ {
		field := t.Field(i)
		fmt.Println("DomainInterface:", field.Name)
	}

	var isource libvirtxml.DomainInterfaceSource
	listFields(isource, "libvirtxml.DomainInterfaceSource")

	var ibridge libvirtxml.DomainInterfaceSourceBridge
	listFields(ibridge, "libvirtxml.DomainInterfaceSourceBridge")
}

func listFields(a any, name string) {
	t := reflect.TypeOf(a)

	fmt.Println("Fields in", name)
	for i := 0; i < t.NumField(); i++ {
		field := t.Field(i)
		fmt.Println(name, field.Name)
	}
}

// dump out all the fields in libvirtxml.DomainDeviceList
func libvirtxmlDomainDevicesEmpty(mydom libvirtxml.DomainDeviceList) bool {
	var empty bool = true
	// Get the reflection object of the variable
	v := reflect.ValueOf(mydom)

	// Ensure that we are working with a struct
	if v.Kind() == reflect.Struct {
		// fmt.Println("Fields and values in libvirtxml.DomainDeviceList:")

		// Loop through each field in the struct
		for i := 0; i < v.NumField(); i++ {
			// Get field name
			field := v.Type().Field(i).Name

			// Get field value
			value := v.Field(i)

			if !value.IsValid() {
				fmt.Printf("Field: %s is nil or invalid\n", field)
				continue
			}

			// Check if the field is a string, array, or slice
			switch value.Kind() {
			case reflect.String:
				if value.String() != "" {
					fmt.Printf("Field: %s is a String with value: %s\n", field, value.String())
					empty = false
				}
			case reflect.Slice:
				if value.Len() != 0 {
					fmt.Printf("Field: %s is a Slice with length: %d\n", field, value.Len())
					empty = false
				}
			case reflect.Array:
				if value.Len() != 0 {
					fmt.Printf("Field: %s is an Array with length: %d\n", field, value.Len())
					empty = false
				}
			case reflect.Ptr:
				if !value.IsValid() {
					fmt.Println("Field ptr: value:", value)
					fmt.Printf("Field ptr: %s is of type: %s\n", field, value.Kind())
					empty = false
				}
			default:
				fmt.Printf("Field: %s is of type: %s\n", field, value.Kind())
				empty = false
			}
			// Print the field name and value
			// fmt.Printf("Field: %s, Value: %v\n", field, value)
		}
	} else {
		fmt.Println("Provided variable is not a struct.")
	}
	return empty
}

// dump out all the fields in libvirtxml.DomainDeviceList
func libvirtxmlDomainEmpty(mydom libvirtxml.Domain) bool {
	var empty bool = true
	// Get the reflection object of the variable
	v := reflect.ValueOf(mydom)

	// Ensure that we are working with a struct
	if v.Kind() == reflect.Struct {
		// fmt.Println("Fields and values in libvirtxml.DomainDeviceList:")

		// Loop through each field in the struct
		for i := 0; i < v.NumField(); i++ {
			// Get field name
			field := v.Type().Field(i).Name

			// Get field value
			value := v.Field(i)

			if !value.IsValid() {
				fmt.Printf("Field: %s is invalid\n", field)
				continue
			}
			// processed as Domain.Metadata & Domain.Resource
			// if (field == "IOThreads") || (field == "XMLName") {
			// 	fmt.Printf("Field: %s is: %s\n", field, value.String())
			// 	continue
			// }

			// Check if the field is a string, array, or slice
			switch value.Kind() {
			case reflect.String:
				if value.String() != "" {
					fmt.Printf("Field: %s is a String with value: %s\n", field, value.String())
					empty = false
				}
			case reflect.Slice:
				if value.Len() != 0 {
					fmt.Printf("Field: %s is a Slice with length: %d\n", field, value.Len())
					empty = false
				}
			case reflect.Array:
				if value.Len() != 0 {
					fmt.Printf("Field: %s is an Array with length: %d\n", field, value.Len())
					empty = false
				}
			case reflect.Struct:
				if IsStructEmptyOrNil(value) {
					// fmt.Printf("XML Field ignore empty Struct %s\n", field)
				} else {
					fmt.Printf("Field Struct is not empty %s is %+v\n", field, value)
					empty = false
				}
			case reflect.Uint:
				// probably ignore ints. when has that ever gone wrong?
			case reflect.Ptr:
				if value.IsValid() {
					if value.IsNil() {
						// this means the value is actually nil
					} else {
						// there is something still here in the libvirt XML
						fmt.Printf("Field Valid? field %s is of type: %s\n", field, value.Kind())
						fmt.Println("Field Valid? ptr: value:", value)
						empty = false
					}
				} else {
					fmt.Println("Invalid Field ptr: value:", value)
					fmt.Printf("Invalid Field ptr: %s is of type: %s\n", field, value.Kind())
					empty = false
				}
			default:
				fmt.Printf("Field: %s is of type: %s\n", field, value.Kind())
				empty = false
			}
			// Print the field name and value
			// fmt.Printf("Field: %s, Value: %v\n", field, value)
		}
	} else {
		fmt.Println("Provided variable is not a struct.")
	}
	return empty
}

// IsStructEmptyOrNil checks if a struct or pointer to struct is empty, blank, or nil
func IsStructEmptyOrNil(value interface{}) bool {
	val := reflect.ValueOf(value)

	// If the value is a pointer, check if it's nil and dereference it if not
	if val.Kind() == reflect.Ptr {
		if val.IsNil() {
			return true
		}
		val = val.Elem()
	}

	// Ensure we're dealing with a struct after potential dereferencing
	if val.Kind() != reflect.Struct {
		return false // Not a struct
	}

	// Check each field in the struct for its zero value
	for i := 0; i < val.NumField(); i++ {
		field := val.Field(i)
		// Skip unexported fields as we can't access them
		if !field.CanInterface() {
			continue
		}
		if !reflect.DeepEqual(field.Interface(), reflect.Zero(field.Type()).Interface()) {
			return false // Found a non-zero field
		}
	}

	return true // All fields are zero values
}