Add support for Windows ARM64

Use system call instead of GOARCH to support Windows userspace x86 emulation, as well as native arm

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

pkg/machine/fedora.go

@@ -18,7 +18,8 @@ import (
 )
 
 const (
-	githubLatestReleaseURL = "https://github.com/containers/podman-wsl-fedora/releases/latest/download/rootfs.tar.xz"
+	githubX86ReleaseURL = "https://github.com/containers/podman-wsl-fedora/releases/latest/download/rootfs.tar.xz"
+	githubArmReleaseURL = "https://github.com/containers/podman-wsl-fedora-arm/releases/latest/download/rootfs.tar.xz"
 )
 
 type FedoraDownload struct {
@@ -26,7 +27,7 @@ type FedoraDownload struct {
 }
 
 func NewFedoraDownloader(vmType, vmName, releaseStream string) (DistributionDownload, error) {
-	downloadURL, version, size, err := getFedoraDownload(githubLatestReleaseURL)
+	downloadURL, version, arch, size, err := getFedoraDownload()
 	if err != nil {
 		return nil, err
 	}
@@ -36,7 +37,7 @@ func NewFedoraDownloader(vmType, vmName, releaseStream string) (DistributionDown
 		return nil, err
 	}
 
-	imageName := fmt.Sprintf("fedora-podman-%s.tar.xz", version)
+	imageName := fmt.Sprintf("fedora-podman-%s-%s.tar.xz", arch, version)
 
 	f := FedoraDownload{
 		Download: Download{
@@ -80,21 +81,32 @@ func (f FedoraDownload) CleanCache() error {
 	return removeImageAfterExpire(f.CacheDir, expire)
 }
 
-func getFedoraDownload(releaseURL string) (*url.URL, string, int64, error) {
+func getFedoraDownload() (*url.URL, string, string, int64, error) {
+	var releaseURL string
+	arch := determineFedoraArch()
+	switch arch {
+	case "arm64":
+		releaseURL = githubArmReleaseURL
+	case "amd64":
+		releaseURL = githubX86ReleaseURL
+	default:
+		return nil, "", "", -1, fmt.Errorf("CPU architecture %q is not supported", arch)
+	}
+
 	downloadURL, err := url.Parse(releaseURL)
 	if err != nil {
-		return nil, "", -1, fmt.Errorf("invalid URL generated from discovered Fedora file: %s: %w", releaseURL, err)
+		return nil, "", "", -1, fmt.Errorf("invalid URL generated from discovered Fedora file: %s: %w", releaseURL, err)
 	}
 
 	resp, err := http.Head(releaseURL)
 	if err != nil {
-		return nil, "", -1, fmt.Errorf("head request failed: %s: %w", releaseURL, err)
+		return nil, "", "", -1, fmt.Errorf("head request failed: %s: %w", releaseURL, err)
 	}
 	_ = resp.Body.Close()
 	contentLen := resp.ContentLength
 
 	if resp.StatusCode != http.StatusOK {
-		return nil, "", -1, fmt.Errorf("head request failed: %s: %w", releaseURL, err)
+		return nil, "", "", -1, fmt.Errorf("head request failed: %s: %w", releaseURL, err)
 	}
 
 	verURL := *downloadURL
@@ -102,14 +114,14 @@ func getFedoraDownload(releaseURL string) (*url.URL, string, int64, error) {
 
 	resp, err = http.Get(verURL.String())
 	if err != nil {
-		return nil, "", -1, fmt.Errorf("get request failed: %s: %w", verURL.String(), err)
+		return nil, "", "", -1, fmt.Errorf("get request failed: %s: %w", verURL.String(), err)
 	}
 
 	defer resp.Body.Close()
 	bytes, err := io.ReadAll(&io.LimitedReader{R: resp.Body, N: 1024})
 	if err != nil {
-		return nil, "", -1, fmt.Errorf("failed reading: %s: %w", verURL.String(), err)
+		return nil, "", "", -1, fmt.Errorf("failed reading: %s: %w", verURL.String(), err)
 	}
 
-	return downloadURL, strings.TrimSpace(string(bytes)), contentLen, nil
+	return downloadURL, strings.TrimSpace(string(bytes)), arch, contentLen, nil
 }

pkg/machine/fedora_unix.go

@@ -0,0 +1,12 @@
+//go:build darwin || dragonfly || freebsd || linux || netbsd || openbsd
+// +build darwin dragonfly freebsd linux netbsd openbsd
+
+package machine
+
+import (
+	"runtime"
+)
+
+func determineFedoraArch() string {
+	return runtime.GOARCH
+}

pkg/machine/fedora_windows.go

@@ -0,0 +1,32 @@
+package machine
+
+import (
+	"runtime"
+	"syscall"
+
+	"github.com/sirupsen/logrus"
+	"golang.org/x/sys/windows"
+)
+
+func determineFedoraArch() string {
+	const fallbackMsg = "this may result in the wrong Linux arch under emulation"
+	var machine, native uint16
+	current, _ := syscall.GetCurrentProcess()
+
+	if err := windows.IsWow64Process2(windows.Handle(current), &machine, &native); err != nil {
+		logrus.Warnf("Failure detecting native system architecture, %s: %w", fallbackMsg, err)
+		// Fall-back to binary arch
+		return runtime.GOARCH
+	}
+
+	switch native {
+	// Only care about archs in use with WSL
+	case 0xAA64:
+		return "arm64"
+	case 0x8664:
+		return "amd64"
+	default:
+		logrus.Warnf("Unknown or unsupported native system architecture [%d], %s", fallbackMsg)
+		return runtime.GOARCH
+	}
+}