Files
kubernetes/vendor/github.com/opencontainers/runc/libcontainer/cgroups/fs2/defaultpath.go
Kir Kolyshkin 1d4f88b1ee vendor: bump runc to v1.2.1
For one thing, this release decouples device management from
libcontainer/cgroups. You can see the result of this in a dropped
cilium/ebpf dependency (which is only needed for device management).

NOTE that due to an issue with go mod / go list,
github.com/opencontainers/runc had to be added to
hack/unwanted-dependencies.json under x/exp. This is bogus because
opencontainers/runc does not use x/exp directly, only via cilium/ebpf
dependency (which is not vendored here).

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2024-11-01 17:26:09 -07:00

103 lines
2.9 KiB
Go

/*
Copyright The containerd Authors.
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 fs2
import (
"bufio"
"errors"
"fmt"
"io"
"os"
"path/filepath"
"strings"
"github.com/opencontainers/runc/libcontainer/configs"
"github.com/opencontainers/runc/libcontainer/utils"
)
const UnifiedMountpoint = "/sys/fs/cgroup"
func defaultDirPath(c *configs.Cgroup) (string, error) {
if (c.Name != "" || c.Parent != "") && c.Path != "" {
return "", fmt.Errorf("cgroup: either Path or Name and Parent should be used, got %+v", c)
}
return _defaultDirPath(UnifiedMountpoint, c.Path, c.Parent, c.Name)
}
func _defaultDirPath(root, cgPath, cgParent, cgName string) (string, error) {
if (cgName != "" || cgParent != "") && cgPath != "" {
return "", errors.New("cgroup: either Path or Name and Parent should be used")
}
// XXX: Do not remove CleanPath. Path safety is important! -- cyphar
innerPath := utils.CleanPath(cgPath)
if innerPath == "" {
cgParent := utils.CleanPath(cgParent)
cgName := utils.CleanPath(cgName)
innerPath = filepath.Join(cgParent, cgName)
}
if filepath.IsAbs(innerPath) {
return filepath.Join(root, innerPath), nil
}
// 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.
ownCgroup, err := parseCgroupFile("/proc/self/cgroup")
if err != nil {
return "", err
}
// The current user scope most probably has tasks in it already,
// making it impossible to enable controllers for its sub-cgroup.
// A parent cgroup (with no tasks in it) is what we need.
ownCgroup = filepath.Dir(ownCgroup)
return filepath.Join(root, ownCgroup, innerPath), nil
}
// parseCgroupFile parses /proc/PID/cgroup file and return string
func parseCgroupFile(path string) (string, error) {
f, err := os.Open(path)
if err != nil {
return "", err
}
defer f.Close()
return parseCgroupFromReader(f)
}
func parseCgroupFromReader(r io.Reader) (string, error) {
s := bufio.NewScanner(r)
for s.Scan() {
var (
text = s.Text()
parts = strings.SplitN(text, ":", 3)
)
if len(parts) < 3 {
return "", fmt.Errorf("invalid cgroup entry: %q", text)
}
// text is like "0::/user.slice/user-1001.slice/session-1.scope"
if parts[0] == "0" && parts[1] == "" {
return parts[2], nil
}
}
if err := s.Err(); err != nil {
return "", err
}
return "", errors.New("cgroup path not found")
}