.golangci.yml: add nolintlint, fix found issues

The errrolint linter can finally ignore errors from Close,
and it also ignores direct comparisons of errors from x/sys/unix.

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>

.golangci.yml

@@ -8,6 +8,7 @@ linters:
   enable:
     - gofumpt
     - errorlint
+    - nolintlint
     - unconvert
     - unparam
 

libcontainer/factory_linux_test.go

@@ -86,7 +86,7 @@ func marshal(path string, v interface{}) error {
 	if err != nil {
 		return err
 	}
-	defer f.Close() //nolint: errcheck
+	defer f.Close()
 	return utils.WriteJSON(f, v)
 }
 

libcontainer/integration/checkpoint_test.go

@@ -67,7 +67,7 @@ func testCheckpoint(t *testing.T, userns bool) {
 
 	err = container.Run(&pconfig)
 	_ = stdinR.Close()
-	defer stdinW.Close() //nolint: errcheck
+	defer stdinW.Close()
 	ok(t, err)
 
 	pid, err := pconfig.Pid()
@@ -141,7 +141,7 @@ func testCheckpoint(t *testing.T, userns bool) {
 
 	err = container.Restore(restoreProcessConfig, checkpointOpts)
 	_ = restoreStdinR.Close()
-	defer restoreStdinW.Close() //nolint: errcheck
+	defer restoreStdinW.Close()
 	if err != nil {
 		t.Fatal(err)
 	}

libcontainer/integration/exec_test.go

@@ -172,7 +172,7 @@ func TestEnter(t *testing.T) {
 	}
 	err = container.Run(&pconfig)
 	_ = stdinR.Close()
-	defer stdinW.Close() //nolint: errcheck
+	defer stdinW.Close()
 	ok(t, err)
 	pid, err := pconfig.Pid()
 	ok(t, err)
@@ -190,7 +190,7 @@ func TestEnter(t *testing.T) {
 
 	err = container.Run(&pconfig2)
 	_ = stdinR2.Close()
-	defer stdinW2.Close() //nolint: errcheck
+	defer stdinW2.Close()
 	ok(t, err)
 
 	pid2, err := pconfig2.Pid()
@@ -458,7 +458,7 @@ func testFreeze(t *testing.T, withSystemd bool, useSet bool) {
 	}
 	err = container.Run(pconfig)
 	_ = stdinR.Close()
-	defer stdinW.Close() //nolint: errcheck
+	defer stdinW.Close()
 	ok(t, err)
 
 	if !useSet {
@@ -738,7 +738,7 @@ func TestContainerState(t *testing.T) {
 	err = container.Run(p)
 	ok(t, err)
 	_ = stdinR.Close()
-	defer stdinW.Close() //nolint: errcheck
+	defer stdinW.Close()
 
 	st, err := container.State()
 	ok(t, err)
@@ -1164,7 +1164,7 @@ func TestRootfsPropagationSlaveMount(t *testing.T) {
 
 	err = container.Run(pconfig)
 	_ = stdinR.Close()
-	defer stdinW.Close() //nolint: errcheck
+	defer stdinW.Close()
 	ok(t, err)
 
 	// Create mnt2host under dir1host and bind mount itself on top of it.
@@ -1194,7 +1194,7 @@ func TestRootfsPropagationSlaveMount(t *testing.T) {
 
 	err = container.Run(pconfig2)
 	_ = stdinR2.Close()
-	defer stdinW2.Close() //nolint: errcheck
+	defer stdinW2.Close()
 	ok(t, err)
 
 	_ = stdinW2.Close()
@@ -1276,7 +1276,7 @@ func TestRootfsPropagationSharedMount(t *testing.T) {
 
 	err = container.Run(pconfig)
 	_ = stdinR.Close()
-	defer stdinW.Close() //nolint: errcheck
+	defer stdinW.Close()
 	ok(t, err)
 
 	// Create mnt2cont under dir1host. This will become visible inside container
@@ -1311,7 +1311,7 @@ func TestRootfsPropagationSharedMount(t *testing.T) {
 
 	err = container.Run(pconfig2)
 	_ = stdinR2.Close()
-	defer stdinW2.Close() //nolint: errcheck
+	defer stdinW2.Close()
 	ok(t, err)
 
 	// Wait for process
@@ -1430,7 +1430,7 @@ func TestInitJoinPID(t *testing.T) {
 	}
 	err = container1.Run(init1)
 	_ = stdinR1.Close()
-	defer stdinW1.Close() //nolint: errcheck
+	defer stdinW1.Close()
 	ok(t, err)
 
 	// get the state of the first container
@@ -1457,7 +1457,7 @@ func TestInitJoinPID(t *testing.T) {
 	}
 	err = container2.Run(init2)
 	_ = stdinR2.Close()
-	defer stdinW2.Close() //nolint: errcheck
+	defer stdinW2.Close()
 	ok(t, err)
 	// get the state of the second container
 	state2, err := container2.State()
@@ -1529,7 +1529,7 @@ func TestInitJoinNetworkAndUser(t *testing.T) {
 	}
 	err = container1.Run(init1)
 	_ = stdinR1.Close()
-	defer stdinW1.Close() //nolint: errcheck
+	defer stdinW1.Close()
 	ok(t, err)
 
 	// get the state of the first container
@@ -1563,7 +1563,7 @@ func TestInitJoinNetworkAndUser(t *testing.T) {
 	}
 	err = container2.Run(init2)
 	_ = stdinR2.Close()
-	defer stdinW2.Close() //nolint: errcheck
+	defer stdinW2.Close()
 	ok(t, err)
 
 	// get the state of the second container

libcontainer/integration/execin_test.go

@@ -40,7 +40,7 @@ func TestExecIn(t *testing.T) {
 	}
 	err = container.Run(process)
 	_ = stdinR.Close()
-	defer stdinW.Close() //nolint: errcheck
+	defer stdinW.Close()
 	ok(t, err)
 
 	buffers := newStdBuffers()
@@ -98,7 +98,7 @@ func testExecInRlimit(t *testing.T, userns bool) {
 	}
 	err = container.Run(process)
 	_ = stdinR.Close()
-	defer stdinW.Close() //nolint: errcheck
+	defer stdinW.Close()
 	ok(t, err)
 
 	buffers := newStdBuffers()
@@ -149,7 +149,7 @@ func TestExecInAdditionalGroups(t *testing.T) {
 	}
 	err = container.Run(process)
 	_ = stdinR.Close()
-	defer stdinW.Close() //nolint: errcheck
+	defer stdinW.Close()
 	ok(t, err)
 
 	var stdout bytes.Buffer
@@ -338,7 +338,7 @@ func TestExecInEnvironment(t *testing.T) {
 	}
 	err = container.Run(process)
 	_ = stdinR.Close()
-	defer stdinW.Close() //nolint: errcheck
+	defer stdinW.Close()
 	ok(t, err)
 
 	execEnv := []string{
@@ -408,7 +408,7 @@ func TestExecinPassExtraFiles(t *testing.T) {
 	}
 	err = container.Run(process)
 	_ = stdinR.Close()
-	defer stdinW.Close() //nolint: errcheck
+	defer stdinW.Close()
 	ok(t, err)
 
 	var stdout bytes.Buffer
@@ -473,7 +473,7 @@ func TestExecInOomScoreAdj(t *testing.T) {
 	}
 	err = container.Run(process)
 	_ = stdinR.Close()
-	defer stdinW.Close() //nolint: errcheck
+	defer stdinW.Close()
 	ok(t, err)
 
 	buffers := newStdBuffers()
@@ -521,7 +521,7 @@ func TestExecInUserns(t *testing.T) {
 	}
 	err = container.Run(process)
 	_ = stdinR.Close()
-	defer stdinW.Close() //nolint: errcheck
+	defer stdinW.Close()
 	ok(t, err)
 
 	initPID, err := process.Pid()

libcontainer/rootfs_linux.go

@@ -873,7 +873,7 @@ func reOpenDevNull() error {
 	if err != nil {
 		return err
 	}
-	defer file.Close() //nolint: errcheck
+	defer file.Close()
 	if err := unix.Fstat(int(file.Fd()), &devNullStat); err != nil {
 		return &os.PathError{Op: "fstat", Path: file.Name(), Err: err}
 	}
@@ -999,7 +999,7 @@ func rootfsParentMountPrivate(path string) error {
 		if err == nil {
 			return nil
 		}
-		if err != unix.EINVAL || path == "/" { //nolint:errorlint // unix errors are bare
+		if err != unix.EINVAL || path == "/" {
 			break
 		}
 		path = filepath.Dir(path)
@@ -1067,13 +1067,13 @@ func pivotRoot(rootfs string) error {
 	if err != nil {
 		return &os.PathError{Op: "open", Path: "/", Err: err}
 	}
-	defer unix.Close(oldroot) //nolint: errcheck
+	defer unix.Close(oldroot)
 
 	newroot, err := unix.Open(rootfs, unix.O_DIRECTORY|unix.O_RDONLY, 0)
 	if err != nil {
 		return &os.PathError{Op: "open", Path: rootfs, Err: err}
 	}
-	defer unix.Close(newroot) //nolint: errcheck
+	defer unix.Close(newroot)
 
 	// Change to the new root so that the pivot_root actually acts on it.
 	if err := unix.Fchdir(newroot); err != nil {

libcontainer/utils/cmsg.go

@@ -49,7 +49,7 @@ func RecvFile(socket *os.File) (_ *os.File, Err error) {
 
 	for {
 		n, oobn, _, _, err = unix.Recvmsg(int(sockfd), name, oob, unix.MSG_CMSG_CLOEXEC)
-		if err != unix.EINTR { //nolint:errorlint // unix errors are bare
+		if err != unix.EINTR {
 			break
 		}
 	}
@@ -128,7 +128,7 @@ func SendRawFd(socket *os.File, msg string, fd uintptr) error {
 	oob := unix.UnixRights(int(fd))
 	for {
 		err := unix.Sendmsg(int(socket.Fd()), []byte(msg), oob, nil, 0)
-		if err != unix.EINTR { //nolint:errorlint // unix errors are bare
+		if err != unix.EINTR {
 			return os.NewSyscallError("sendmsg", err)
 		}
 	}