refactor: replace the ioutil by the os and io

Signed-off-by: saltbo <saltbo@foxmail.com>

pkg/util/filesystem/defaultfs.go

@@ -17,14 +17,13 @@ limitations under the License.
 package filesystem
 
 import (
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strings"
 	"time"
 )
 
-// DefaultFs implements Filesystem using same-named functions from "os" and "io/ioutil"
+// DefaultFs implements Filesystem using same-named functions from "os" and "io"
 type DefaultFs struct {
 	root string
 }
@@ -33,10 +32,7 @@ var _ Filesystem = &DefaultFs{}
 
 // NewTempFs returns a fake Filesystem in temporary directory, useful for unit tests
 func NewTempFs() Filesystem {
-	path, _ := ioutil.TempDir(
-		"",
-		"tmpfs",
-	)
+	path, _ := os.MkdirTemp("", "tmpfs")
 	return &DefaultFs{
 		root: path,
 	}
@@ -94,28 +90,28 @@ func (fs *DefaultFs) Remove(name string) error {
 	return os.Remove(fs.prefix(name))
 }
 
-// ReadFile via ioutil.ReadFile
+// ReadFile via os.ReadFile
 func (fs *DefaultFs) ReadFile(filename string) ([]byte, error) {
-	return ioutil.ReadFile(fs.prefix(filename))
+	return os.ReadFile(fs.prefix(filename))
 }
 
-// TempDir via ioutil.TempDir
+// TempDir via os.MkdirTemp
 func (fs *DefaultFs) TempDir(dir, prefix string) (string, error) {
-	return ioutil.TempDir(fs.prefix(dir), prefix)
+	return os.MkdirTemp(fs.prefix(dir), prefix)
 }
 
-// TempFile via ioutil.TempFile
+// TempFile via os.CreateTemp
 func (fs *DefaultFs) TempFile(dir, prefix string) (File, error) {
-	file, err := ioutil.TempFile(fs.prefix(dir), prefix)
+	file, err := os.CreateTemp(fs.prefix(dir), prefix)
 	if err != nil {
 		return nil, err
 	}
 	return &defaultFile{file}, nil
 }
 
-// ReadDir via ioutil.ReadDir
-func (fs *DefaultFs) ReadDir(dirname string) ([]os.FileInfo, error) {
-	return ioutil.ReadDir(fs.prefix(dirname))
+// ReadDir via os.ReadDir
+func (fs *DefaultFs) ReadDir(dirname string) ([]os.DirEntry, error) {
+	return os.ReadDir(fs.prefix(dirname))
 }
 
 // Walk via filepath.Walk

pkg/util/filesystem/filesystem.go

@@ -37,7 +37,7 @@ type Filesystem interface {
 	ReadFile(filename string) ([]byte, error)
 	TempDir(dir, prefix string) (string, error)
 	TempFile(dir, prefix string) (File, error)
-	ReadDir(dirname string) ([]os.FileInfo, error)
+	ReadDir(dirname string) ([]os.DirEntry, error)
 	Walk(root string, walkFn filepath.WalkFunc) error
 }
 

pkg/util/oom/oom_linux.go

@@ -21,7 +21,6 @@ package oom
 
 import (
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path"
 	"path/filepath"
@@ -66,7 +65,7 @@ func applyOOMScoreAdj(pid int, oomScoreAdj int) error {
 	klog.V(4).Infof("attempting to set %q to %q", oomScoreAdjPath, value)
 	var err error
 	for i := 0; i < maxTries; i++ {
-		err = ioutil.WriteFile(oomScoreAdjPath, []byte(value), 0700)
+		err = os.WriteFile(oomScoreAdjPath, []byte(value), 0700)
 		if err != nil {
 			if os.IsNotExist(err) {
 				klog.V(2).Infof("%q does not exist", oomScoreAdjPath)

pkg/util/procfs/procfs_linux.go

@@ -23,7 +23,6 @@ import (
 	"bytes"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"os"
 	"path"
 	"path/filepath"
@@ -61,7 +60,7 @@ func containerNameFromProcCgroup(content string) (string, error) {
 // return docker/nginx. Assumes that the process is part of exactly one cgroup hierarchy.
 func (pfs *ProcFS) GetFullContainerName(pid int) (string, error) {
 	filePath := path.Join("/proc", strconv.Itoa(pid), "cgroup")
-	content, err := ioutil.ReadFile(filePath)
+	content, err := os.ReadFile(filePath)
 	if err != nil {
 		if os.IsNotExist(err) {
 			return "", os.ErrNotExist
@@ -138,7 +137,7 @@ func getPids(re *regexp.Regexp) []int {
 				continue
 			}
 
-			cmdline, err := ioutil.ReadFile(filepath.Join("/proc", entry.Name(), "cmdline"))
+			cmdline, err := os.ReadFile(filepath.Join("/proc", entry.Name(), "cmdline"))
 			if err != nil {
 				klog.V(4).Infof("Error reading file %s: %+v", filepath.Join("/proc", entry.Name(), "cmdline"), err)
 				continue

pkg/util/procfs/procfs_linux_test.go

@@ -20,7 +20,6 @@ limitations under the License.
 package procfs
 
 import (
-	"io/ioutil"
 	"os"
 	"os/signal"
 	"path/filepath"
@@ -56,7 +55,7 @@ func TestContainerNameFromProcCgroup(t *testing.T) {
 	procCgroupEmpty := ""
 	verifyContainerName(procCgroupEmpty, "", true, t)
 
-	content, err := ioutil.ReadFile("example_proc_cgroup")
+	content, err := os.ReadFile("example_proc_cgroup")
 	if err != nil {
 		t.Errorf("Could not read example /proc cgroup file")
 	}

pkg/util/tail/tail.go

@@ -19,7 +19,6 @@ package tail
 import (
 	"bytes"
 	"io"
-	"io/ioutil"
 	"os"
 )
 
@@ -57,7 +56,7 @@ func ReadAtMost(path string, max int64) ([]byte, bool, error) {
 	if err != nil {
 		return nil, false, err
 	}
-	data, err := ioutil.ReadAll(f)
+	data, err := io.ReadAll(f)
 	return data, offset > 0, err
 }
 

pkg/util/tail/tail_test.go

@@ -18,14 +18,13 @@ package tail
 
 import (
 	"bytes"
-	"io/ioutil"
 	"os"
 	"strings"
 	"testing"
 )
 
 func TestReadAtMost(t *testing.T) {
-	file, err := ioutil.TempFile("", "TestFileReadAtMost")
+	file, err := os.CreateTemp("", "TestFileReadAtMost")
 	if err != nil {
 		t.Fatalf("unable to create temp file")
 	}