Implements Windows volume/mount support

Based on WSL2 9p support: remaps windows paths to /mnt/<drive> locations for
both podman and Docker API clients.

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

2 files changed, 90 insertions, 8 deletions

diff --git a/pkg/specgenutil/specgenutil_test.go b/pkg/specgenutil/specgenutil_test.go
new file mode 100644
index 000000000..5867b0ae0
--- /dev/null
+++ b/pkg/specgenutil/specgenutil_test.go
@@ -0,0 +1,77 @@
+//go:build linux
+// +build linux
+
+package specgenutil
+
+import (
+	"testing"
+
+	"github.com/containers/common/pkg/machine"
+	"github.com/containers/podman/v4/pkg/domain/entities"
+	"github.com/containers/podman/v4/pkg/specgen"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestWinPath(t *testing.T) {
+	const (
+		fail = false
+		pass = true
+	)
+	tests := []struct {
+		vol     string
+		source  string
+		dest    string
+		isN     bool
+		outcome bool
+		mach    string
+	}{
+		{`C:\Foo:/blah`, "/mnt/c/Foo", "/blah", false, pass, "wsl"},
+		{`C:\Foo:/blah`, "/mnt/c/Foo", "/blah", false, fail, ""},
+		{`\\?\C:\Foo:/blah`, "/mnt/c/Foo", "/blah", false, pass, "wsl"},
+		{`/c/bar:/blah`, "/mnt/c/bar", "/blah", false, pass, "wsl"},
+		{`/c/bar:/blah`, "/c/bar", "/blah", false, pass, ""},
+		{`/test/this:/blah`, "/test/this", "/blah", false, pass, "wsl"},
+		{`c:/bar/something:/other`, "/mnt/c/bar/something", "/other", false, pass, "wsl"},
+		{`c:/foo:ro`, "c", "/foo", true, pass, ""},
+		{`\\computer\loc:/dest`, "", "", false, fail, "wsl"},
+		{`\\.\drive\loc:/target`, "/mnt/wsl/drive/loc", "/target", false, pass, "wsl"},
+	}
+
+	f := func(vol string, mach string) (*specgen.SpecGenerator, error) {
+		machine := machine.GetMachineMarker()
+		oldEnable, oldType := machine.Enabled, machine.Type
+		machine.Enabled, machine.Type = len(mach) > 0, mach
+		sg := specgen.NewSpecGenerator("nothing", false)
+		err := FillOutSpecGen(sg, &entities.ContainerCreateOptions{
+			ImageVolume: "ignore",
+			Volume:      []string{vol}}, []string{},
+		)
+		machine.Enabled, machine.Type = oldEnable, oldType
+		return sg, err
+	}
+
+	for _, test := range tests {
+		msg := "Checking: " + test.vol
+		sg, err := f(test.vol, test.mach)
+		if test.outcome == fail {
+			assert.NotNil(t, err, msg)
+			continue
+		}
+		if !assert.Nil(t, err, msg) {
+			continue
+		}
+		if test.isN {
+			if !assert.Equal(t, 1, len(sg.Volumes), msg) {
+				continue
+			}
+			assert.Equal(t, test.source, sg.Volumes[0].Name, msg)
+			assert.Equal(t, test.dest, sg.Volumes[0].Dest, msg)
+		} else {
+			if !assert.Equal(t, 1, len(sg.Mounts), msg) {
+				continue
+			}
+			assert.Equal(t, test.source, sg.Mounts[0].Source, msg)
+			assert.Equal(t, test.dest, sg.Mounts[0].Destination, msg)
+		}
+	}
+}
diff --git a/pkg/specgenutil/volumes.go b/pkg/specgenutil/volumes.go
index 95ce420f8..50d745380 100644
--- a/pkg/specgenutil/volumes.go
+++ b/pkg/specgenutil/volumes.go
@@ -3,7 +3,7 @@ package specgenutil
 import (
 	"encoding/csv"
 	"fmt"
-	"path/filepath"
+	"path"
 	"strings"
 
 	"github.com/containers/common/pkg/parse"
@@ -123,7 +123,7 @@ func parseVolumes(volumeFlag, mountFlag, tmpfsFlag []string, addReadOnlyTmpfs bo
 	finalMounts := make([]spec.Mount, 0, len(unifiedMounts))
 	for _, mount := range unifiedMounts {
 		if mount.Type == define.TypeBind {
-			absSrc, err := filepath.Abs(mount.Source)
+			absSrc, err := specgen.ConvertWinMountPath(mount.Source)
 			if err != nil {
 				return nil, nil, nil, nil, errors.Wrapf(err, "error getting absolute path of %s", mount.Source)
 			}
@@ -334,7 +334,7 @@ func getBindMount(args []string) (spec.Mount, error) {
 			if err := parse.ValidateVolumeCtrDir(kv[1]); err != nil {
 				return newMount, err
 			}
-			newMount.Destination = filepath.Clean(kv[1])
+			newMount.Destination = unixPathClean(kv[1])
 			setDest = true
 		case "relabel":
 			if setRelabel {
@@ -456,7 +456,7 @@ func getTmpfsMount(args []string) (spec.Mount, error) {
 			if err := parse.ValidateVolumeCtrDir(kv[1]); err != nil {
 				return newMount, err
 			}
-			newMount.Destination = filepath.Clean(kv[1])
+			newMount.Destination = unixPathClean(kv[1])
 			setDest = true
 		case "U", "chown":
 			if setOwnership {
@@ -507,7 +507,7 @@ func getDevptsMount(args []string) (spec.Mount, error) {
 			if err := parse.ValidateVolumeCtrDir(kv[1]); err != nil {
 				return newMount, err
 			}
-			newMount.Destination = filepath.Clean(kv[1])
+			newMount.Destination = unixPathClean(kv[1])
 			setDest = true
 		default:
 			return newMount, errors.Wrapf(util.ErrBadMntOption, "%s", kv[0])
@@ -572,7 +572,7 @@ func getNamedVolume(args []string) (*specgen.NamedVolume, error) {
 			if err := parse.ValidateVolumeCtrDir(kv[1]); err != nil {
 				return nil, err
 			}
-			newVolume.Dest = filepath.Clean(kv[1])
+			newVolume.Dest = unixPathClean(kv[1])
 			setDest = true
 		case "U", "chown":
 			if setOwnership {
@@ -624,7 +624,7 @@ func getImageVolume(args []string) (*specgen.ImageVolume, error) {
 			if err := parse.ValidateVolumeCtrDir(kv[1]); err != nil {
 				return nil, err
 			}
-			newVolume.Destination = filepath.Clean(kv[1])
+			newVolume.Destination = unixPathClean(kv[1])
 		case "rw", "readwrite":
 			switch kv[1] {
 			case "true":
@@ -670,7 +670,7 @@ func getTmpfsMounts(tmpfsFlag []string) (map[string]spec.Mount, error) {
 		}
 
 		mount := spec.Mount{
-			Destination: filepath.Clean(destPath),
+			Destination: unixPathClean(destPath),
 			Type:        define.TypeTmpfs,
 			Options:     options,
 			Source:      define.TypeTmpfs,
@@ -700,3 +700,8 @@ func validChownFlag(flag string) (bool, error) {
 
 	return true, nil
 }
+
+// Use path instead of filepath to preserve Unix style paths on Windows
+func unixPathClean(p string) string {
+	return path.Clean(p)
+}