020ec43b56
Volume mounting logic introduced in #43775 and #45623 checks for subPath existence before attempting to create a directory, should subPath not be present. This breaks if subPath is a dangling symlink, os.Stat returns "do not exist" status, yet `os.MkdirAll` can't create directory as symlink is present at the given path. This patch makes existence check to use os.Lstat which works for normal files/directories as well as doesn't not attempt to follow symlink, therefore it's "do not exist" status is more reliable when making a decision whether to create directory or not. subPath symlinks can be dangling in situations where kubelet is running in a container itself with access to docker socket, such as CoreOS's kubelet-wrapper script
141 lines
3.5 KiB
Go
141 lines
3.5 KiB
Go
/*
|
|
Copyright 2014 The Kubernetes Authors.
|
|
|
|
Licensed under the Apache License, Version 2.0 (the "License");
|
|
you may not use this file except in compliance with the License.
|
|
You may obtain a copy of the License at
|
|
|
|
http://www.apache.org/licenses/LICENSE-2.0
|
|
|
|
Unless required by applicable law or agreed to in writing, software
|
|
distributed under the License is distributed on an "AS IS" BASIS,
|
|
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
See the License for the specific language governing permissions and
|
|
limitations under the License.
|
|
*/
|
|
|
|
package util
|
|
|
|
import (
|
|
"fmt"
|
|
"os"
|
|
"reflect"
|
|
"regexp"
|
|
)
|
|
|
|
// Takes a list of strings and compiles them into a list of regular expressions
|
|
func CompileRegexps(regexpStrings []string) ([]*regexp.Regexp, error) {
|
|
regexps := []*regexp.Regexp{}
|
|
for _, regexpStr := range regexpStrings {
|
|
r, err := regexp.Compile(regexpStr)
|
|
if err != nil {
|
|
return []*regexp.Regexp{}, err
|
|
}
|
|
regexps = append(regexps, r)
|
|
}
|
|
return regexps, nil
|
|
}
|
|
|
|
// Detects if using systemd as the init system
|
|
// Please note that simply reading /proc/1/cmdline can be misleading because
|
|
// some installation of various init programs can automatically make /sbin/init
|
|
// a symlink or even a renamed version of their main program.
|
|
// TODO(dchen1107): realiably detects the init system using on the system:
|
|
// systemd, upstart, initd, etc.
|
|
func UsingSystemdInitSystem() bool {
|
|
if _, err := os.Stat("/run/systemd/system"); err == nil {
|
|
return true
|
|
}
|
|
|
|
return false
|
|
}
|
|
|
|
// Tests whether all pointer fields in a struct are nil. This is useful when,
|
|
// for example, an API struct is handled by plugins which need to distinguish
|
|
// "no plugin accepted this spec" from "this spec is empty".
|
|
//
|
|
// This function is only valid for structs and pointers to structs. Any other
|
|
// type will cause a panic. Passing a typed nil pointer will return true.
|
|
func AllPtrFieldsNil(obj interface{}) bool {
|
|
v := reflect.ValueOf(obj)
|
|
if !v.IsValid() {
|
|
panic(fmt.Sprintf("reflect.ValueOf() produced a non-valid Value for %#v", obj))
|
|
}
|
|
if v.Kind() == reflect.Ptr {
|
|
if v.IsNil() {
|
|
return true
|
|
}
|
|
v = v.Elem()
|
|
}
|
|
for i := 0; i < v.NumField(); i++ {
|
|
if v.Field(i).Kind() == reflect.Ptr && !v.Field(i).IsNil() {
|
|
return false
|
|
}
|
|
}
|
|
return true
|
|
}
|
|
|
|
func FileExists(filename string) (bool, error) {
|
|
if _, err := os.Stat(filename); os.IsNotExist(err) {
|
|
return false, nil
|
|
} else if err != nil {
|
|
return false, err
|
|
}
|
|
return true, nil
|
|
}
|
|
|
|
func FileOrSymlinkExists(filename string) (bool, error) {
|
|
if _, err := os.Lstat(filename); os.IsNotExist(err) {
|
|
return false, nil
|
|
} else if err != nil {
|
|
return false, err
|
|
}
|
|
return true, nil
|
|
}
|
|
|
|
// ReadDirNoStat returns a string of files/directories contained
|
|
// in dirname without calling lstat on them.
|
|
func ReadDirNoStat(dirname string) ([]string, error) {
|
|
if dirname == "" {
|
|
dirname = "."
|
|
}
|
|
|
|
f, err := os.Open(dirname)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
defer f.Close()
|
|
|
|
return f.Readdirnames(-1)
|
|
}
|
|
|
|
// IntPtr returns a pointer to an int
|
|
func IntPtr(i int) *int {
|
|
o := i
|
|
return &o
|
|
}
|
|
|
|
// Int32Ptr returns a pointer to an int32
|
|
func Int32Ptr(i int32) *int32 {
|
|
o := i
|
|
return &o
|
|
}
|
|
|
|
// IntPtrDerefOr dereference the int ptr and returns it i not nil,
|
|
// else returns def.
|
|
func IntPtrDerefOr(ptr *int, def int) int {
|
|
if ptr != nil {
|
|
return *ptr
|
|
}
|
|
return def
|
|
}
|
|
|
|
// Int32PtrDerefOr dereference the int32 ptr and returns it i not nil,
|
|
// else returns def.
|
|
func Int32PtrDerefOr(ptr *int32, def int32) int32 {
|
|
if ptr != nil {
|
|
return *ptr
|
|
}
|
|
return def
|
|
}
|