fs: abstract away filesystem ops from nodeFromFileInfo

internal/archiver/archiver.go

@@ -264,6 +264,10 @@ func (arch *Archiver) trackItem(item string, previous, current *restic.Node, s I
 // nodeFromFileInfo returns the restic node from an os.FileInfo.
 func (arch *Archiver) nodeFromFileInfo(snPath, filename string, meta ToNoder, ignoreXattrListError bool) (*restic.Node, error) {
 	node, err := meta.ToNode(ignoreXattrListError)
+	if node == nil {
+		// do not filter error on total failure
+		return node, err
+	}
 	if !arch.WithAtime {
 		node.AccessTime = node.ModTime
 	}

internal/fs/file_windows.go

@@ -8,7 +8,6 @@ import (
 	"strings"
 	"time"
 
-	"github.com/restic/restic/internal/restic"
 	"golang.org/x/sys/windows"
 )
 
@@ -115,22 +114,13 @@ func clearAttribute(path string, attribute uint32) error {
 }
 
 // openHandleForEA return a file handle for file or dir for setting/getting EAs
-func openHandleForEA(nodeType restic.NodeType, path string, writeAccess bool) (handle windows.Handle, err error) {
+func openHandleForEA(path string, writeAccess bool) (handle windows.Handle, err error) {
 	path = fixpath(path)
 	fileAccess := windows.FILE_READ_EA
 	if writeAccess {
 		fileAccess = fileAccess | windows.FILE_WRITE_EA
 	}
 
-	switch nodeType {
-	case restic.NodeTypeFile:
-		utf16Path := windows.StringToUTF16Ptr(path)
-		handle, err = windows.CreateFile(utf16Path, uint32(fileAccess), 0, nil, windows.OPEN_EXISTING, windows.FILE_ATTRIBUTE_NORMAL, 0)
-	case restic.NodeTypeDir:
-		utf16Path := windows.StringToUTF16Ptr(path)
-		handle, err = windows.CreateFile(utf16Path, uint32(fileAccess), 0, nil, windows.OPEN_EXISTING, windows.FILE_ATTRIBUTE_NORMAL|windows.FILE_FLAG_BACKUP_SEMANTICS, 0)
-	default:
-		return 0, nil
-	}
-	return handle, err
+	utf16Path := windows.StringToUTF16Ptr(path)
+	return windows.CreateFile(utf16Path, uint32(fileAccess), 0, nil, windows.OPEN_EXISTING, windows.FILE_ATTRIBUTE_NORMAL|windows.FILE_FLAG_BACKUP_SEMANTICS, 0)
 }

internal/fs/fs_local.go

@@ -90,12 +90,14 @@ type localFile struct {
 	flag int
 	f    *os.File
 	fi   *ExtendedFileInfo
+	meta metadataHandle
 }
 
 // See the File interface for a description of each method
 var _ File = &localFile{}
 
 func newLocalFile(name string, flag int, metadataOnly bool) (*localFile, error) {
+	meta := newPathMetadataHandle(name, flag)
 	var f *os.File
 	if !metadataOnly {
 		var err error
@@ -105,11 +107,14 @@ func newLocalFile(name string, flag int, metadataOnly bool) (*localFile, error)
 		}
 		_ = setFlags(f)
 	}
-	return &localFile{
+	file := &localFile{
 		name: name,
 		flag: flag,
 		f:    f,
-	}, nil
+		meta: meta,
+	}
+
+	return file, nil
 }
 
 func (f *localFile) MakeReadable() error {
@@ -130,20 +135,17 @@ func (f *localFile) cacheFI() error {
 	if f.fi != nil {
 		return nil
 	}
-	var fi os.FileInfo
 	var err error
 	if f.f != nil {
-		fi, err = f.f.Stat()
-	} else if f.flag&O_NOFOLLOW != 0 {
-		fi, err = os.Lstat(f.name)
+		fi, err := f.f.Stat()
+		if err != nil {
+			return err
+		}
+		f.fi = extendedStat(fi)
 	} else {
-		fi, err = os.Stat(f.name)
+		f.fi, err = f.meta.Stat()
 	}
-	if err != nil {
-		return err
-	}
-	f.fi = extendedStat(fi)
-	return nil
+	return err
 }
 
 func (f *localFile) Stat() (*ExtendedFileInfo, error) {
@@ -156,7 +158,7 @@ func (f *localFile) ToNode(ignoreXattrListError bool) (*restic.Node, error) {
 	if err := f.cacheFI(); err != nil {
 		return nil, err
 	}
-	return nodeFromFileInfo(f.name, f.fi, ignoreXattrListError)
+	return nodeFromFileInfo(f.name, &cachedMetadataHandle{f.meta, f}, ignoreXattrListError)
 }
 
 func (f *localFile) Read(p []byte) (n int, err error) {
@@ -173,3 +175,14 @@ func (f *localFile) Close() error {
 	}
 	return nil
 }
+
+// metadata handle with FileInfo from localFile
+// This ensures that Stat() and ToNode() use the exact same data.
+type cachedMetadataHandle struct {
+	metadataHandle
+	f *localFile
+}
+
+func (c *cachedMetadataHandle) Stat() (*ExtendedFileInfo, error) {
+	return c.f.Stat()
+}

internal/fs/meta.go

@@ -0,0 +1,52 @@
+package fs
+
+import (
+	"os"
+
+	"github.com/restic/restic/internal/restic"
+)
+
+type metadataHandle interface {
+	Name() string
+	Stat() (*ExtendedFileInfo, error)
+	Readlink() (string, error)
+	Xattr(ignoreListError bool) ([]restic.ExtendedAttribute, error)
+	// windows only
+	SecurityDescriptor() (*[]byte, error)
+}
+
+type pathMetadataHandle struct {
+	name string
+	flag int
+}
+
+var _ metadataHandle = &pathMetadataHandle{}
+
+func newPathMetadataHandle(name string, flag int) *pathMetadataHandle {
+	return &pathMetadataHandle{
+		name: fixpath(name),
+		flag: flag,
+	}
+}
+
+func (p *pathMetadataHandle) Name() string {
+	return p.name
+}
+
+func (p *pathMetadataHandle) Stat() (*ExtendedFileInfo, error) {
+	var fi os.FileInfo
+	var err error
+	if p.flag&O_NOFOLLOW != 0 {
+		fi, err = os.Lstat(p.name)
+	} else {
+		fi, err = os.Stat(p.name)
+	}
+	if err != nil {
+		return nil, err
+	}
+	return extendedStat(fi), nil
+}
+
+func (p *pathMetadataHandle) Readlink() (string, error) {
+	return os.Readlink(p.name)
+}

internal/fs/meta_noxattr.go

@@ -0,0 +1,10 @@
+//go:build aix || dragonfly || netbsd || openbsd
+// +build aix dragonfly netbsd openbsd
+
+package fs
+
+import "github.com/restic/restic/internal/restic"
+
+func (p *pathMetadataHandle) Xattr(ignoreListError bool) ([]restic.ExtendedAttribute, error) {
+	return nil, nil
+}

internal/fs/meta_unix.go

@@ -0,0 +1,8 @@
+//go:build !windows
+// +build !windows
+
+package fs
+
+func (p *pathMetadataHandle) SecurityDescriptor() (*[]byte, error) {
+	return nil, nil
+}

internal/fs/meta_windows.go

@@ -0,0 +1,47 @@
+package fs
+
+import (
+	"github.com/restic/restic/internal/debug"
+	"github.com/restic/restic/internal/errors"
+	"github.com/restic/restic/internal/restic"
+	"golang.org/x/sys/windows"
+)
+
+func (p *pathMetadataHandle) Xattr(_ bool) ([]restic.ExtendedAttribute, error) {
+	allowExtended, err := checkAndStoreEASupport(p.name)
+	if err != nil || !allowExtended {
+		return nil, err
+	}
+
+	var fileHandle windows.Handle
+	if fileHandle, err = openHandleForEA(p.name, false); err != nil {
+		return nil, errors.Errorf("get EA failed while opening file handle for path %v, with: %v", p.name, err)
+	}
+	defer closeFileHandle(fileHandle, p.name)
+
+	//Get the windows Extended Attributes using the file handle
+	var extAtts []extendedAttribute
+	extAtts, err = fgetEA(fileHandle)
+	debug.Log("fillExtendedAttributes(%v) %v", p.name, extAtts)
+	if err != nil {
+		return nil, errors.Errorf("get EA failed for path %v, with: %v", p.name, err)
+	}
+	if len(extAtts) == 0 {
+		return nil, nil
+	}
+
+	extendedAttrs := make([]restic.ExtendedAttribute, 0, len(extAtts))
+	for _, attr := range extAtts {
+		extendedAttr := restic.ExtendedAttribute{
+			Name:  attr.Name,
+			Value: attr.Value,
+		}
+
+		extendedAttrs = append(extendedAttrs, extendedAttr)
+	}
+	return extendedAttrs, nil
+}
+
+func (p *pathMetadataHandle) SecurityDescriptor() (*[]byte, error) {
+	return getSecurityDescriptor(p.name)
+}

internal/fs/meta_xattr.go

@@ -0,0 +1,40 @@
+//go:build darwin || freebsd || linux || solaris
+// +build darwin freebsd linux solaris
+
+package fs
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/restic/restic/internal/debug"
+	"github.com/restic/restic/internal/restic"
+)
+
+func (p *pathMetadataHandle) Xattr(ignoreListError bool) ([]restic.ExtendedAttribute, error) {
+	xattrs, err := listxattr(p.name)
+	debug.Log("fillExtendedAttributes(%v) %v %v", p.name, xattrs, err)
+	if err != nil {
+		if ignoreListError && isListxattrPermissionError(err) {
+			return nil, nil
+		}
+		return nil, err
+	}
+
+	extendedAttrs := make([]restic.ExtendedAttribute, 0, len(xattrs))
+	for _, attr := range xattrs {
+		attrVal, err := getxattr(p.name, attr)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "can not obtain extended attribute %v for %v:\n", attr, p.name)
+			continue
+		}
+		attr := restic.ExtendedAttribute{
+			Name:  attr,
+			Value: attrVal,
+		}
+
+		extendedAttrs = append(extendedAttrs, attr)
+	}
+
+	return extendedAttrs, nil
+}

internal/fs/node.go

@@ -13,17 +13,22 @@ import (
 	"github.com/restic/restic/internal/restic"
 )
 
-// nodeFromFileInfo returns a new node from the given path and FileInfo. It
-// returns the first error that is encountered, together with a node.
-func nodeFromFileInfo(path string, fi *ExtendedFileInfo, ignoreXattrListError bool) (*restic.Node, error) {
+// nodeFromFileInfo returns a new node from the given path and metadata handle.
+// Can return a nil node if no file metadata can be retrieved. Otherwise, it returns
+// the first error that is encountered, together with a node.
+func nodeFromFileInfo(path string, meta metadataHandle, ignoreXattrListError bool) (*restic.Node, error) {
+	fi, err := meta.Stat()
+	if err != nil {
+		return nil, err
+	}
 	node := buildBasicNode(path, fi)
 
-	if err := nodeFillExtendedStat(node, path, fi); err != nil {
+	if err := nodeFillExtendedStat(node, meta, fi); err != nil {
 		return node, err
 	}
 
-	err := nodeFillGenericAttributes(node, path, fi)
-	err = errors.Join(err, nodeFillExtendedAttributes(node, path, ignoreXattrListError))
+	err = nodeFillGenericAttributes(node, meta, fi)
+	err = errors.Join(err, nodeFillExtendedAttributes(node, meta, ignoreXattrListError))
 	return node, err
 }
 
@@ -66,7 +71,7 @@ func nodeTypeFromFileInfo(mode os.FileMode) restic.NodeType {
 	return restic.NodeTypeInvalid
 }
 
-func nodeFillExtendedStat(node *restic.Node, path string, stat *ExtendedFileInfo) error {
+func nodeFillExtendedStat(node *restic.Node, meta metadataHandle, stat *ExtendedFileInfo) error {
 	node.Inode = stat.Inode
 	node.DeviceID = stat.DeviceID
 	node.ChangeTime = stat.ChangeTime
@@ -84,7 +89,7 @@ func nodeFillExtendedStat(node *restic.Node, path string, stat *ExtendedFileInfo
 	case restic.NodeTypeDir:
 	case restic.NodeTypeSymlink:
 		var err error
-		node.LinkTarget, err = os.Readlink(fixpath(path))
+		node.LinkTarget, err = meta.Readlink()
 		node.Links = stat.Links
 		if err != nil {
 			return errors.WithStack(err)

internal/fs/node_noxattr.go

@@ -13,6 +13,6 @@ func nodeRestoreExtendedAttributes(_ *restic.Node, _ string) error {
 }
 
 // nodeFillExtendedAttributes is a no-op
-func nodeFillExtendedAttributes(_ *restic.Node, _ string, _ bool) error {
+func nodeFillExtendedAttributes(_ *restic.Node, _ metadataHandle, _ bool) error {
 	return nil
 }

internal/fs/node_unix.go

@@ -19,6 +19,6 @@ func nodeRestoreGenericAttributes(node *restic.Node, _ string, warn func(msg str
 }
 
 // nodeFillGenericAttributes is a no-op.
-func nodeFillGenericAttributes(_ *restic.Node, _ string, _ *ExtendedFileInfo) error {
+func nodeFillGenericAttributes(_ *restic.Node, _ metadataHandle, _ *ExtendedFileInfo) error {
 	return nil
 }

internal/fs/node_windows.go

@@ -84,56 +84,18 @@ func nodeRestoreExtendedAttributes(node *restic.Node, path string) (err error) {
 }
 
 // fill extended attributes in the node
-// It also checks if the volume supports extended attributes and stores the result in a map
-// so that it does not have to be checked again for subsequent calls for paths in the same volume.
-func nodeFillExtendedAttributes(node *restic.Node, path string, _ bool) (err error) {
-	if strings.Contains(filepath.Base(path), ":") {
+func nodeFillExtendedAttributes(node *restic.Node, meta metadataHandle, _ bool) (err error) {
+	if strings.Contains(filepath.Base(meta.Name()), ":") {
 		// Do not process for Alternate Data Streams in Windows
 		return nil
 	}
-
 	// only capture xattrs for file/dir
 	if node.Type != restic.NodeTypeFile && node.Type != restic.NodeTypeDir {
 		return nil
 	}
 
-	allowExtended, err := checkAndStoreEASupport(path)
-	if err != nil {
-		return err
-	}
-	if !allowExtended {
-		return nil
-	}
-
-	var fileHandle windows.Handle
-	if fileHandle, err = openHandleForEA(node.Type, path, false); fileHandle == 0 {
-		return nil
-	}
-	if err != nil {
-		return errors.Errorf("get EA failed while opening file handle for path %v, with: %v", path, err)
-	}
-	defer closeFileHandle(fileHandle, path) // Replaced inline defer with named function call
-	//Get the windows Extended Attributes using the file handle
-	var extAtts []extendedAttribute
-	extAtts, err = fgetEA(fileHandle)
-	debug.Log("fillExtendedAttributes(%v) %v", path, extAtts)
-	if err != nil {
-		return errors.Errorf("get EA failed for path %v, with: %v", path, err)
-	}
-	if len(extAtts) == 0 {
-		return nil
-	}
-
-	//Fill the ExtendedAttributes in the node using the name/value pairs in the windows EA
-	for _, attr := range extAtts {
-		extendedAttr := restic.ExtendedAttribute{
-			Name:  attr.Name,
-			Value: attr.Value,
-		}
-
-		node.ExtendedAttributes = append(node.ExtendedAttributes, extendedAttr)
-	}
-	return nil
+	node.ExtendedAttributes, err = meta.Xattr(false)
+	return err
 }
 
 // closeFileHandle safely closes a file handle and logs any errors.
@@ -147,11 +109,13 @@ func closeFileHandle(fileHandle windows.Handle, path string) {
 // restoreExtendedAttributes handles restore of the Windows Extended Attributes to the specified path.
 // The Windows API requires setting of all the Extended Attributes in one call.
 func restoreExtendedAttributes(nodeType restic.NodeType, path string, eas []extendedAttribute) (err error) {
-	var fileHandle windows.Handle
-	if fileHandle, err = openHandleForEA(nodeType, path, true); fileHandle == 0 {
+	// only restore xattrs for file/dir
+	if nodeType != restic.NodeTypeFile && nodeType != restic.NodeTypeDir {
 		return nil
 	}
-	if err != nil {
+
+	var fileHandle windows.Handle
+	if fileHandle, err = openHandleForEA(path, true); err != nil {
 		return errors.Errorf("set EA failed while opening file handle for path %v, with: %v", path, err)
 	}
 	defer closeFileHandle(fileHandle, path) // Replaced inline defer with named function call
@@ -336,7 +300,8 @@ func decryptFile(pathPointer *uint16) error {
 
 // nodeFillGenericAttributes fills in the generic attributes for windows like File Attributes,
 // Created time and Security Descriptors.
-func nodeFillGenericAttributes(node *restic.Node, path string, stat *ExtendedFileInfo) error {
+func nodeFillGenericAttributes(node *restic.Node, meta metadataHandle, stat *ExtendedFileInfo) error {
+	path := meta.Name()
 	if strings.Contains(filepath.Base(path), ":") {
 		// Do not process for Alternate Data Streams in Windows
 		return nil
@@ -356,7 +321,7 @@ func nodeFillGenericAttributes(node *restic.Node, path string, stat *ExtendedFil
 
 	var sd *[]byte
 	if node.Type == restic.NodeTypeFile || node.Type == restic.NodeTypeDir {
-		if sd, err = getSecurityDescriptor(path); err != nil {
+		if sd, err = meta.SecurityDescriptor(); err != nil {
 			return err
 		}
 	}

internal/fs/node_xattr.go

@@ -4,11 +4,9 @@
 package fs
 
 import (
-	"fmt"
 	"os"
 	"syscall"
 
-	"github.com/restic/restic/internal/debug"
 	"github.com/restic/restic/internal/errors"
 	"github.com/restic/restic/internal/restic"
 
@@ -92,30 +90,8 @@ func nodeRestoreExtendedAttributes(node *restic.Node, path string) error {
 	return nil
 }
 
-func nodeFillExtendedAttributes(node *restic.Node, path string, ignoreListError bool) error {
-	xattrs, err := listxattr(path)
-	debug.Log("fillExtendedAttributes(%v) %v %v", path, xattrs, err)
-	if err != nil {
-		if ignoreListError && isListxattrPermissionError(err) {
-			return nil
-		}
-		return err
-	}
-
-	node.ExtendedAttributes = make([]restic.ExtendedAttribute, 0, len(xattrs))
-	for _, attr := range xattrs {
-		attrVal, err := getxattr(path, attr)
-		if err != nil {
-			fmt.Fprintf(os.Stderr, "can not obtain extended attribute %v for %v:\n", attr, path)
-			continue
-		}
-		attr := restic.ExtendedAttribute{
-			Name:  attr,
-			Value: attrVal,
-		}
-
-		node.ExtendedAttributes = append(node.ExtendedAttributes, attr)
-	}
-
-	return nil
+func nodeFillExtendedAttributes(node *restic.Node, meta metadataHandle, ignoreListError bool) error {
+	var err error
+	node.ExtendedAttributes, err = meta.Xattr(ignoreListError)
+	return err
 }

internal/fs/node_xattr_all_test.go

@@ -31,7 +31,8 @@ func setAndVerifyXattr(t *testing.T, file string, attrs []restic.ExtendedAttribu
 	nodeActual := &restic.Node{
 		Type: restic.NodeTypeFile,
 	}
-	rtest.OK(t, nodeFillExtendedAttributes(nodeActual, file, false))
+	meta := newPathMetadataHandle(file, 0)
+	rtest.OK(t, nodeFillExtendedAttributes(nodeActual, meta, false))
 
 	rtest.Assert(t, nodeActual.Equals(*node), "xattr mismatch got %v expected %v", nodeActual.ExtendedAttributes, node.ExtendedAttributes)
 }