Switch to new vendor directory layout

Fixes #113

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

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

@@ -0,0 +1,63 @@
+// +build linux
+
+package fs
+
+import (
+	"fmt"
+	"strconv"
+
+	"github.com/opencontainers/runc/libcontainer/cgroups"
+	"github.com/opencontainers/runc/libcontainer/configs"
+)
+
+type PidsGroup struct {
+}
+
+func (s *PidsGroup) Name() string {
+	return "pids"
+}
+
+func (s *PidsGroup) Apply(d *cgroupData) error {
+	_, err := d.join("pids")
+	if err != nil && !cgroups.IsNotFound(err) {
+		return err
+	}
+	return nil
+}
+
+func (s *PidsGroup) Set(path string, cgroup *configs.Cgroup) error {
+	if cgroup.Resources.PidsLimit != 0 {
+		// "max" is the fallback value.
+		limit := "max"
+
+		if cgroup.Resources.PidsLimit > 0 {
+			limit = strconv.FormatInt(cgroup.Resources.PidsLimit, 10)
+		}
+
+		if err := writeFile(path, "pids.max", limit); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (s *PidsGroup) Remove(d *cgroupData) error {
+	return removePath(d.path("pids"))
+}
+
+func (s *PidsGroup) GetStats(path string, stats *cgroups.Stats) error {
+	current, err := getCgroupParamUint(path, "pids.current")
+	if err != nil {
+		return fmt.Errorf("failed to parse pids.current - %s", err)
+	}
+
+	max, err := getCgroupParamUint(path, "pids.max")
+	if err != nil {
+		return fmt.Errorf("failed to parse pids.max - %s", err)
+	}
+
+	stats.PidsStats.Current = current
+	stats.PidsStats.Max = max
+	return nil
+}