package fs2
import (
"errors"
"math"
"os"
"strings"
"golang.org/x/sys/unix"
"github.com/opencontainers/runc/libcontainer/cgroups"
"github.com/opencontainers/runc/libcontainer/cgroups/fscommon"
"github.com/opencontainers/runc/libcontainer/configs"
)
func isPidsSet(r *configs.Resources) bool {
return r.PidsLimit != 0
}
func setPids(dirPath string, r *configs.Resources) error {
if !isPidsSet(r) {
return nil
}
if val := numToStr(r.PidsLimit); val != "" {
if err := cgroups.WriteFile(dirPath, "pids.max", val); err != nil {
return err
}
}
return nil
}
func statPidsFromCgroupProcs(dirPath string, stats *cgroups.Stats) error {
// if the controller is not enabled, let's read PIDS from cgroups.procs
// (or threads if cgroup.threads is enabled)
contents, err := cgroups.ReadFile(dirPath, "cgroup.procs")
if errors.Is(err, unix.ENOTSUP) {
contents, err = cgroups.ReadFile(dirPath, "cgroup.threads")
}
if err != nil {
return err
}
pids := strings.Count(contents, "\n")
stats.PidsStats.Current = uint64(pids)
stats.PidsStats.Limit = 0
return nil
}
func statPids(dirPath string, stats *cgroups.Stats) error {
current, err := fscommon.GetCgroupParamUint(dirPath, "pids.current")
if err != nil {
if os.IsNotExist(err) {
return statPidsFromCgroupProcs(dirPath, stats)
}
return err
}
max, err := fscommon.GetCgroupParamUint(dirPath, "pids.max")
if err != nil {
return err
}
// If no limit is set, read from pids.max returns "max", which is
// converted to MaxUint64 by GetCgroupParamUint. Historically, we
// represent "no limit" for pids as 0, thus this conversion.
if max == math.MaxUint64 {
max = 0
}
stats.PidsStats.Current = current
stats.PidsStats.Limit = max
return nil
}