rebase: update replaced k8s.io modules to v0.33.0

Signed-off-by: Niels de Vos <ndevos@ibm.com>

e2e/vendor/github.com/opencontainers/cgroups/v1_utils.go

@@ -0,0 +1,277 @@
+package cgroups
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+	"sync"
+	"syscall"
+
+	securejoin "github.com/cyphar/filepath-securejoin"
+	"github.com/moby/sys/mountinfo"
+	"golang.org/x/sys/unix"
+)
+
+// Code in this source file are specific to cgroup v1,
+// and must not be used from any cgroup v2 code.
+
+const (
+	CgroupNamePrefix = "name="
+	defaultPrefix    = "/sys/fs/cgroup"
+)
+
+var (
+	errUnified     = errors.New("not implemented for cgroup v2 unified hierarchy")
+	ErrV1NoUnified = errors.New("invalid configuration: cannot use unified on cgroup v1")
+
+	readMountinfoOnce sync.Once
+	readMountinfoErr  error
+	cgroupMountinfo   []*mountinfo.Info
+)
+
+type NotFoundError struct {
+	Subsystem string
+}
+
+func (e *NotFoundError) Error() string {
+	return fmt.Sprintf("mountpoint for %s not found", e.Subsystem)
+}
+
+func NewNotFoundError(sub string) error {
+	return &NotFoundError{
+		Subsystem: sub,
+	}
+}
+
+func IsNotFound(err error) bool {
+	var nfErr *NotFoundError
+	return errors.As(err, &nfErr)
+}
+
+func tryDefaultPath(cgroupPath, subsystem string) string {
+	if !strings.HasPrefix(defaultPrefix, cgroupPath) {
+		return ""
+	}
+
+	// remove possible prefix
+	subsystem = strings.TrimPrefix(subsystem, CgroupNamePrefix)
+
+	// Make sure we're still under defaultPrefix, and resolve
+	// a possible symlink (like cpu -> cpu,cpuacct).
+	path, err := securejoin.SecureJoin(defaultPrefix, subsystem)
+	if err != nil {
+		return ""
+	}
+
+	// (1) path should be a directory.
+	st, err := os.Lstat(path)
+	if err != nil || !st.IsDir() {
+		return ""
+	}
+
+	// (2) path should be a mount point.
+	pst, err := os.Lstat(filepath.Dir(path))
+	if err != nil {
+		return ""
+	}
+
+	if st.Sys().(*syscall.Stat_t).Dev == pst.Sys().(*syscall.Stat_t).Dev {
+		// parent dir has the same dev -- path is not a mount point
+		return ""
+	}
+
+	// (3) path should have 'cgroup' fs type.
+	fst := unix.Statfs_t{}
+	err = unix.Statfs(path, &fst)
+	if err != nil || fst.Type != unix.CGROUP_SUPER_MAGIC {
+		return ""
+	}
+
+	return path
+}
+
+// readCgroupMountinfo returns a list of cgroup v1 mounts (i.e. the ones
+// with fstype of "cgroup") for the current running process.
+//
+// The results are cached (to avoid re-reading mountinfo which is relatively
+// expensive), so it is assumed that cgroup mounts are not being changed.
+func readCgroupMountinfo() ([]*mountinfo.Info, error) {
+	readMountinfoOnce.Do(func() {
+		// mountinfo.GetMounts uses /proc/thread-self, so we can use it without
+		// issues.
+		cgroupMountinfo, readMountinfoErr = mountinfo.GetMounts(
+			mountinfo.FSTypeFilter("cgroup"),
+		)
+	})
+	return cgroupMountinfo, readMountinfoErr
+}
+
+// https://www.kernel.org/doc/Documentation/cgroup-v1/cgroups.txt
+func FindCgroupMountpoint(cgroupPath, subsystem string) (string, error) {
+	if IsCgroup2UnifiedMode() {
+		return "", errUnified
+	}
+
+	// If subsystem is empty, we look for the cgroupv2 hybrid path.
+	if len(subsystem) == 0 {
+		return hybridMountpoint, nil
+	}
+
+	// Avoid parsing mountinfo by trying the default path first, if possible.
+	if path := tryDefaultPath(cgroupPath, subsystem); path != "" {
+		return path, nil
+	}
+
+	mnt, _, err := FindCgroupMountpointAndRoot(cgroupPath, subsystem)
+	return mnt, err
+}
+
+func FindCgroupMountpointAndRoot(cgroupPath, subsystem string) (string, string, error) {
+	if IsCgroup2UnifiedMode() {
+		return "", "", errUnified
+	}
+
+	mi, err := readCgroupMountinfo()
+	if err != nil {
+		return "", "", err
+	}
+
+	return findCgroupMountpointAndRootFromMI(mi, cgroupPath, subsystem)
+}
+
+func findCgroupMountpointAndRootFromMI(mounts []*mountinfo.Info, cgroupPath, subsystem string) (string, string, error) {
+	for _, mi := range mounts {
+		if strings.HasPrefix(mi.Mountpoint, cgroupPath) {
+			for _, opt := range strings.Split(mi.VFSOptions, ",") {
+				if opt == subsystem {
+					return mi.Mountpoint, mi.Root, nil
+				}
+			}
+		}
+	}
+
+	return "", "", NewNotFoundError(subsystem)
+}
+
+func (m Mount) GetOwnCgroup(cgroups map[string]string) (string, error) {
+	if len(m.Subsystems) == 0 {
+		return "", errors.New("no subsystem for mount")
+	}
+
+	return getControllerPath(m.Subsystems[0], cgroups)
+}
+
+func getCgroupMountsHelper(ss map[string]bool, mounts []*mountinfo.Info, all bool) ([]Mount, error) {
+	res := make([]Mount, 0, len(ss))
+	numFound := 0
+	for _, mi := range mounts {
+		m := Mount{
+			Mountpoint: mi.Mountpoint,
+			Root:       mi.Root,
+		}
+		for _, opt := range strings.Split(mi.VFSOptions, ",") {
+			seen, known := ss[opt]
+			if !known || (!all && seen) {
+				continue
+			}
+			ss[opt] = true
+			opt = strings.TrimPrefix(opt, CgroupNamePrefix)
+			m.Subsystems = append(m.Subsystems, opt)
+			numFound++
+		}
+		if len(m.Subsystems) > 0 || all {
+			res = append(res, m)
+		}
+		if !all && numFound >= len(ss) {
+			break
+		}
+	}
+	return res, nil
+}
+
+func getCgroupMountsV1(all bool) ([]Mount, error) {
+	mi, err := readCgroupMountinfo()
+	if err != nil {
+		return nil, err
+	}
+
+	// We don't need to use /proc/thread-self here because runc always runs
+	// with every thread in the same cgroup. This lets us avoid having to do
+	// runtime.LockOSThread.
+	allSubsystems, err := ParseCgroupFile("/proc/self/cgroup")
+	if err != nil {
+		return nil, err
+	}
+
+	allMap := make(map[string]bool)
+	for s := range allSubsystems {
+		allMap[s] = false
+	}
+
+	return getCgroupMountsHelper(allMap, mi, all)
+}
+
+// GetOwnCgroup returns the relative path to the cgroup docker is running in.
+func GetOwnCgroup(subsystem string) (string, error) {
+	if IsCgroup2UnifiedMode() {
+		return "", errUnified
+	}
+
+	// We don't need to use /proc/thread-self here because runc always runs
+	// with every thread in the same cgroup. This lets us avoid having to do
+	// runtime.LockOSThread.
+	cgroups, err := ParseCgroupFile("/proc/self/cgroup")
+	if err != nil {
+		return "", err
+	}
+
+	return getControllerPath(subsystem, cgroups)
+}
+
+func GetOwnCgroupPath(subsystem string) (string, error) {
+	cgroup, err := GetOwnCgroup(subsystem)
+	if err != nil {
+		return "", err
+	}
+
+	// If subsystem is empty, we look for the cgroupv2 hybrid path.
+	if len(subsystem) == 0 {
+		return hybridMountpoint, nil
+	}
+
+	return getCgroupPathHelper(subsystem, cgroup)
+}
+
+func getCgroupPathHelper(subsystem, cgroup string) (string, error) {
+	mnt, root, err := FindCgroupMountpointAndRoot("", subsystem)
+	if err != nil {
+		return "", err
+	}
+
+	// This is needed for nested containers, because in /proc/self/cgroup we
+	// see paths from host, which don't exist in container.
+	relCgroup, err := filepath.Rel(root, cgroup)
+	if err != nil {
+		return "", err
+	}
+
+	return filepath.Join(mnt, relCgroup), nil
+}
+
+func getControllerPath(subsystem string, cgroups map[string]string) (string, error) {
+	if IsCgroup2UnifiedMode() {
+		return "", errUnified
+	}
+
+	if p, ok := cgroups[subsystem]; ok {
+		return p, nil
+	}
+
+	if p, ok := cgroups[CgroupNamePrefix+subsystem]; ok {
+		return p, nil
+	}
+
+	return "", NewNotFoundError(subsystem)
+}