vendor c/psgo@v1.3.2

Now supports cgroupsv2.

Fixes: #4192
Signed-off-by: Valentin Rothberg <rothberg@redhat.com>

vendor/github.com/containers/psgo/internal/cgroups/cgroups.go

@@ -0,0 +1,44 @@
+// Copyright 2019 psgo 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 cgroups
+
+import (
+	"sync"
+	"syscall"
+)
+
+const (
+	CgroupRoot        = "/sys/fs/cgroup"
+	cgroup2SuperMagic = 0x63677270
+)
+
+var (
+	isUnifiedOnce sync.Once
+	isUnified     bool
+	isUnifiedErr  error
+)
+
+// IsCgroup2UnifiedMode returns whether we are running in cgroup or cgroupv2 mode.
+func IsCgroup2UnifiedMode() (bool, error) {
+	isUnifiedOnce.Do(func() {
+		var st syscall.Statfs_t
+		if err := syscall.Statfs(CgroupRoot, &st); err != nil {
+			isUnified, isUnifiedErr = false, err
+		} else {
+			isUnified, isUnifiedErr = st.Type == cgroup2SuperMagic, nil
+		}
+	})
+	return isUnified, isUnifiedErr
+}