vendor: github.com/moby/buildkit 5ae9b23c40a9 (master / v0.13.0-dev)

full diff:

- 36ef4d8c0d...f098008783
- d5c1d785b0...5ae9b23c40

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

vendor/github.com/tonistiigi/fsutil/followlinks.go

@@ -1,17 +1,21 @@
 package fsutil
 
 import (
+	"context"
+	gofs "io/fs"
 	"os"
 	"path/filepath"
 	"runtime"
 	"sort"
 	strings "strings"
+	"syscall"
 
 	"github.com/pkg/errors"
+	"github.com/tonistiigi/fsutil/types"
 )
 
-func FollowLinks(root string, paths []string) ([]string, error) {
-	r := &symlinkResolver{root: root, resolved: map[string]struct{}{}}
+func FollowLinks(fs FS, paths []string) ([]string, error) {
+	r := &symlinkResolver{fs: fs, resolved: map[string]struct{}{}}
 	for _, p := range paths {
 		if err := r.append(p); err != nil {
 			return nil, err
@@ -26,7 +30,7 @@ func FollowLinks(root string, paths []string) ([]string, error) {
 }
 
 type symlinkResolver struct {
-	root     string
+	fs       FS
 	resolved map[string]struct{}
 }
 
@@ -76,10 +80,9 @@ func (r *symlinkResolver) append(p string) error {
 }
 
 func (r *symlinkResolver) readSymlink(p string, allowWildcard bool) ([]string, error) {
-	realPath := filepath.Join(r.root, p)
 	base := filepath.Base(p)
 	if allowWildcard && containsWildcards(base) {
-		fis, err := os.ReadDir(filepath.Dir(realPath))
+		fis, err := readDir(r.fs, filepath.Dir(p))
 		if err != nil {
 			if isNotFound(err) {
 				return nil, nil
@@ -99,21 +102,30 @@ func (r *symlinkResolver) readSymlink(p string, allowWildcard bool) ([]string, e
 		return out, nil
 	}
 
-	fi, err := os.Lstat(realPath)
+	entry, err := statFile(r.fs, p)
 	if err != nil {
 		if isNotFound(err) {
 			return nil, nil
 		}
 		return nil, errors.WithStack(err)
 	}
-	if fi.Mode()&os.ModeSymlink == 0 {
+	if entry == nil {
 		return nil, nil
 	}
-	link, err := os.Readlink(realPath)
+	if entry.Type()&os.ModeSymlink == 0 {
+		return nil, nil
+	}
+
+	fi, err := entry.Info()
 	if err != nil {
 		return nil, errors.WithStack(err)
 	}
-	link = filepath.Clean(link)
+	stat, ok := fi.Sys().(*types.Stat)
+	if !ok {
+		return nil, errors.WithStack(&os.PathError{Path: p, Err: syscall.EBADMSG, Op: "fileinfo without stat info"})
+	}
+
+	link := filepath.Clean(stat.Linkname)
 	if filepath.IsAbs(link) {
 		return []string{link}, nil
 	}
@@ -122,6 +134,76 @@ func (r *symlinkResolver) readSymlink(p string, allowWildcard bool) ([]string, e
 	}, nil
 }
 
+func statFile(fs FS, root string) (os.DirEntry, error) {
+	var out os.DirEntry
+
+	root = filepath.Clean(root)
+	if root == "/" || root == "." {
+		return nil, nil
+	}
+
+	err := fs.Walk(context.TODO(), root, func(p string, entry os.DirEntry, err error) error {
+		if err != nil {
+			return err
+		}
+		if p != root {
+			return errors.Errorf("expected single entry %q but got %q", root, p)
+		}
+		out = entry
+		if entry.IsDir() {
+			return filepath.SkipDir
+		}
+		return nil
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	if out == nil {
+		return nil, errors.Wrapf(os.ErrNotExist, "readFile %s", root)
+	}
+	return out, nil
+}
+
+func readDir(fs FS, root string) ([]os.DirEntry, error) {
+	var out []os.DirEntry
+
+	root = filepath.Clean(root)
+	if root == "/" || root == "." {
+		root = "."
+		out = make([]gofs.DirEntry, 0)
+	}
+
+	err := fs.Walk(context.TODO(), root, func(p string, entry os.DirEntry, err error) error {
+		if err != nil {
+			return err
+		}
+		if p == root {
+			if !entry.IsDir() {
+				return errors.WithStack(&os.PathError{Op: "walk", Path: root, Err: syscall.ENOTDIR})
+			}
+			out = make([]gofs.DirEntry, 0)
+			return nil
+		}
+		if out == nil {
+			return errors.Errorf("expected to read parent entry %q before child %q", root, p)
+		}
+		out = append(out, entry)
+		if entry.IsDir() {
+			return filepath.SkipDir
+		}
+		return nil
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	if out == nil && root != "." {
+		return nil, errors.Wrapf(os.ErrNotExist, "readDir %s", root)
+	}
+	return out, nil
+}
+
 func containsWildcards(name string) bool {
 	isWindows := runtime.GOOS == "windows"
 	for i := 0; i < len(name); i++ {