Eliminate transient container deps from wslkerninst

Resolves Win Installer CI issues where dep processing variance can
pull in gpgme, which doesn't compile on Windows without a
specialized msys2 setup.

Signed-off-by: Jason T. Greene <jason.greene@redhat.com>

cmd/podman-wslkerninst/main.go

@@ -11,7 +11,7 @@ import (
 	"time"
 	"unsafe"
 
-	"github.com/containers/podman/v4/pkg/machine/wsl"
+	"github.com/containers/podman/v4/pkg/machine/wsl/wutil"
 	"github.com/sirupsen/logrus"
 	"golang.org/x/sys/windows/svc/eventlog"
 )
@@ -49,7 +49,7 @@ func installWslKernel() error {
 	)
 	backoff := 500 * time.Millisecond
 	for i := 1; i < 6; i++ {
-		err = wsl.SilentExec("wsl", "--update")
+		err = wutil.SilentExec("wsl", "--update")
 		if err == nil {
 			break
 		}
@@ -87,7 +87,7 @@ func warn(title string, caption string) int {
 func main() {
 	args := os.Args
 	setupLogging(path.Base(args[0]))
-	if wsl.IsWSLInstalled() {
+	if wutil.IsWSLInstalled() {
 		// nothing to do
 		logrus.Info("WSL Kernel already installed")
 		return

pkg/machine/wsl/machine.go

@@ -20,6 +20,7 @@ import (
 
 	"github.com/containers/common/pkg/config"
 	"github.com/containers/podman/v4/pkg/machine"
+	"github.com/containers/podman/v4/pkg/machine/wsl/wutil"
 	"github.com/containers/podman/v4/utils"
 	"github.com/containers/storage/pkg/homedir"
 	"github.com/containers/storage/pkg/ioutils"
@@ -695,7 +696,7 @@ func installScripts(dist string) error {
 }
 
 func checkAndInstallWSL(opts machine.InitOptions) (bool, error) {
-	if IsWSLInstalled() {
+	if wutil.IsWSLInstalled() {
 		return true, nil
 	}
 
@@ -1143,35 +1144,8 @@ func getWinProxyStateDir(v *MachineVM) (string, error) {
 	return stateDir, nil
 }
 
-func IsWSLInstalled() bool {
-	cmd := SilentExecCmd("wsl", "--status")
-	out, err := cmd.StdoutPipe()
-	cmd.Stderr = nil
-	if err != nil {
-		return false
-	}
-	if err = cmd.Start(); err != nil {
-		return false
-	}
-	scanner := bufio.NewScanner(transform.NewReader(out, unicode.UTF16(unicode.LittleEndian, unicode.UseBOM).NewDecoder()))
-	result := true
-	for scanner.Scan() {
-		line := scanner.Text()
-		// Windows 11 does not set an error exit code when a kernel is not avail
-		if strings.Contains(line, "kernel file is not found") {
-			result = false
-			break
-		}
-	}
-	if err := cmd.Wait(); !result || err != nil {
-		return false
-	}
-
-	return true
-}
-
 func IsWSLFeatureEnabled() bool {
-	return SilentExec("wsl", "--set-default-version", "2") == nil
+	return wutil.SilentExec("wsl", "--set-default-version", "2") == nil
 }
 
 func isWSLRunning(dist string) (bool, error) {

pkg/machine/wsl/util_windows.go

@@ -8,7 +8,6 @@ import (
 	"errors"
 	"fmt"
 	"os"
-	"os/exec"
 	"path/filepath"
 	"strings"
 	"syscall"
@@ -345,17 +344,3 @@ func sendQuit(tid uint32) {
 	postMessage := user32.NewProc("PostThreadMessageW")
 	postMessage.Call(uintptr(tid), WM_QUIT, 0, 0)
 }
-
-func SilentExec(command string, args ...string) error {
-	cmd := exec.Command(command, args...)
-	cmd.SysProcAttr = &syscall.SysProcAttr{CreationFlags: 0x08000000}
-	cmd.Stdout = nil
-	cmd.Stderr = nil
-	return cmd.Run()
-}
-
-func SilentExecCmd(command string, args ...string) *exec.Cmd {
-	cmd := exec.Command(command, args...)
-	cmd.SysProcAttr = &syscall.SysProcAttr{CreationFlags: 0x08000000}
-	return cmd
-}

pkg/machine/wsl/wutil/wutil.go

@@ -0,0 +1,55 @@
+//go:build windows
+// +build windows
+
+package wutil
+
+import (
+	"bufio"
+	"os/exec"
+	"strings"
+	"syscall"
+
+	"golang.org/x/text/encoding/unicode"
+	"golang.org/x/text/transform"
+)
+
+func SilentExec(command string, args ...string) error {
+	cmd := exec.Command(command, args...)
+	cmd.SysProcAttr = &syscall.SysProcAttr{CreationFlags: 0x08000000}
+	cmd.Stdout = nil
+	cmd.Stderr = nil
+	return cmd.Run()
+}
+
+func SilentExecCmd(command string, args ...string) *exec.Cmd {
+	cmd := exec.Command(command, args...)
+	cmd.SysProcAttr = &syscall.SysProcAttr{CreationFlags: 0x08000000}
+	return cmd
+}
+
+func IsWSLInstalled() bool {
+	cmd := SilentExecCmd("wsl", "--status")
+	out, err := cmd.StdoutPipe()
+	cmd.Stderr = nil
+	if err != nil {
+		return false
+	}
+	if err = cmd.Start(); err != nil {
+		return false
+	}
+	scanner := bufio.NewScanner(transform.NewReader(out, unicode.UTF16(unicode.LittleEndian, unicode.UseBOM).NewDecoder()))
+	result := true
+	for scanner.Scan() {
+		line := scanner.Text()
+		// Windows 11 does not set an error exit code when a kernel is not avail
+		if strings.Contains(line, "kernel file is not found") {
+			result = false
+			break
+		}
+	}
+	if err := cmd.Wait(); !result || err != nil {
+		return false
+	}
+
+	return true
+}