From c6f45fd2eef00d6dcdcf319400c0c6cd891e9d2a Mon Sep 17 00:00:00 2001
From: Phil Estes <estesp@linux.vnet.ibm.com>
Date: Wed, 6 Apr 2016 17:24:17 -0400
Subject: [PATCH] Lazy init useradd and remove init()
This should not have been in init() as it causes these lookups to happen
in all reexecs of the Docker binary. The only time it needs to be
resolved is when a user is added, which is extremely rare.
Docker-DCO-1.1-Signed-off-by: Phil Estes <estesp@linux.vnet.ibm.com>
---
pkg/idtools/usergroupadd_linux.go | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)
diff --git a/pkg/idtools/usergroupadd_linux.go b/pkg/idtools/usergroupadd_linux.go
index 86d9e21e9a..4a4aaed04d 100644
--- a/pkg/idtools/usergroupadd_linux.go
+++ b/pkg/idtools/usergroupadd_linux.go
@@ -8,6 +8,7 @@ import (
"sort"
"strconv"
"strings"
+ "sync"
)
// add a user and/or group to Linux /etc/passwd, /etc/group using standard
@@ -16,6 +17,7 @@ import (
// useradd -r -s /bin/false <username>
var (
+ once sync.Once
userCommand string
cmdTemplates = map[string]string{
@@ -31,15 +33,6 @@ var (
userMod = "usermod"
)
-func init() {
- // set up which commands are used for adding users/groups dependent on distro
- if _, err := resolveBinary("adduser"); err == nil {
- userCommand = "adduser"
- } else if _, err := resolveBinary("useradd"); err == nil {
- userCommand = "useradd"
- }
-}
-
func resolveBinary(binname string) (string, error) {
binaryPath, err := exec.LookPath(binname)
if err != nil {
@@ -94,7 +87,14 @@ func AddNamespaceRangesUser(name string) (int, int, error) {
}
func addUser(userName string) error {
-
+ once.Do(func() {
+ // set up which commands are used for adding users/groups dependent on distro
+ if _, err := resolveBinary("adduser"); err == nil {
+ userCommand = "adduser"
+ } else if _, err := resolveBinary("useradd"); err == nil {
+ userCommand = "useradd"
+ }
+ })
if userCommand == "" {
return fmt.Errorf("Cannot add user; no useradd/adduser binary found")
}