system: always move pause process when running on systemd

when running on a systemd with systemd, always try to move the pause
process to its own scope.

Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
(cherry picked from commit 9c1e27fdd536f6026efe3da4360755a3e9135ca8)

1 files changed, 17 insertions, 0 deletions

diff --git a/utils/utils.go b/utils/utils.go
index 2e415130e..e2760d225 100644
--- a/utils/utils.go
+++ b/utils/utils.go
@@ -4,10 +4,12 @@ import (
 	"bytes"
 	"fmt"
 	"io"
+	"io/ioutil"
 	"os"
 	"os/exec"
 	"strconv"
 	"strings"
+	"sync"
 
 	"github.com/containers/podman/v3/libpod/define"
 	"github.com/containers/storage/pkg/archive"
@@ -155,3 +157,18 @@ func RemoveScientificNotationFromFloat(x float64) (float64, error) {
 	}
 	return result, nil
 }
+
+var (
+	runsOnSystemdOnce sync.Once
+	runsOnSystemd     bool
+)
+
+// RunsOnSystemd returns whether the system is using systemd
+func RunsOnSystemd() bool {
+	runsOnSystemdOnce.Do(func() {
+		initCommand, err := ioutil.ReadFile("/proc/1/comm")
+		// On errors, default to systemd
+		runsOnSystemd = err != nil || strings.TrimRight(string(initCommand), "\n") == "systemd"
+	})
+	return runsOnSystemd
+}