Switch to new vendor directory layout

Fixes #113

Signed-off-by: Marcos Lilljedahl <marcosnils@gmail.com>

vendor/github.com/opencontainers/runc/libcontainer/cgroups/fs/cpuset.go

@@ -0,0 +1,139 @@
+// +build linux
+
+package fs
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"strconv"
+
+	"github.com/opencontainers/runc/libcontainer/cgroups"
+	"github.com/opencontainers/runc/libcontainer/configs"
+	libcontainerUtils "github.com/opencontainers/runc/libcontainer/utils"
+)
+
+type CpusetGroup struct {
+}
+
+func (s *CpusetGroup) Name() string {
+	return "cpuset"
+}
+
+func (s *CpusetGroup) Apply(d *cgroupData) error {
+	dir, err := d.path("cpuset")
+	if err != nil && !cgroups.IsNotFound(err) {
+		return err
+	}
+	return s.ApplyDir(dir, d.config, d.pid)
+}
+
+func (s *CpusetGroup) Set(path string, cgroup *configs.Cgroup) error {
+	if cgroup.Resources.CpusetCpus != "" {
+		if err := writeFile(path, "cpuset.cpus", cgroup.Resources.CpusetCpus); err != nil {
+			return err
+		}
+	}
+	if cgroup.Resources.CpusetMems != "" {
+		if err := writeFile(path, "cpuset.mems", cgroup.Resources.CpusetMems); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (s *CpusetGroup) Remove(d *cgroupData) error {
+	return removePath(d.path("cpuset"))
+}
+
+func (s *CpusetGroup) GetStats(path string, stats *cgroups.Stats) error {
+	return nil
+}
+
+func (s *CpusetGroup) ApplyDir(dir string, cgroup *configs.Cgroup, pid int) error {
+	// This might happen if we have no cpuset cgroup mounted.
+	// Just do nothing and don't fail.
+	if dir == "" {
+		return nil
+	}
+	root, err := getCgroupRoot()
+	if err != nil {
+		return err
+	}
+	if err := s.ensureParent(dir, root); err != nil {
+		return err
+	}
+	// because we are not using d.join we need to place the pid into the procs file
+	// unlike the other subsystems
+	if err := writeFile(dir, "cgroup.procs", strconv.Itoa(pid)); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (s *CpusetGroup) getSubsystemSettings(parent string) (cpus []byte, mems []byte, err error) {
+	if cpus, err = ioutil.ReadFile(filepath.Join(parent, "cpuset.cpus")); err != nil {
+		return
+	}
+	if mems, err = ioutil.ReadFile(filepath.Join(parent, "cpuset.mems")); err != nil {
+		return
+	}
+	return cpus, mems, nil
+}
+
+// ensureParent makes sure that the parent directory of current is created
+// and populated with the proper cpus and mems files copied from
+// it's parent.
+func (s *CpusetGroup) ensureParent(current, root string) error {
+	parent := filepath.Dir(current)
+	if libcontainerUtils.CleanPath(parent) == root {
+		return nil
+	}
+	// Avoid infinite recursion.
+	if parent == current {
+		return fmt.Errorf("cpuset: cgroup parent path outside cgroup root")
+	}
+	if err := s.ensureParent(parent, root); err != nil {
+		return err
+	}
+	if err := os.MkdirAll(current, 0755); err != nil {
+		return err
+	}
+	return s.copyIfNeeded(current, parent)
+}
+
+// copyIfNeeded copies the cpuset.cpus and cpuset.mems from the parent
+// directory to the current directory if the file's contents are 0
+func (s *CpusetGroup) copyIfNeeded(current, parent string) error {
+	var (
+		err                      error
+		currentCpus, currentMems []byte
+		parentCpus, parentMems   []byte
+	)
+
+	if currentCpus, currentMems, err = s.getSubsystemSettings(current); err != nil {
+		return err
+	}
+	if parentCpus, parentMems, err = s.getSubsystemSettings(parent); err != nil {
+		return err
+	}
+
+	if s.isEmpty(currentCpus) {
+		if err := writeFile(current, "cpuset.cpus", string(parentCpus)); err != nil {
+			return err
+		}
+	}
+	if s.isEmpty(currentMems) {
+		if err := writeFile(current, "cpuset.mems", string(parentMems)); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (s *CpusetGroup) isEmpty(b []byte) bool {
+	return len(bytes.Trim(b, "\n")) == 0
+}