Merge pull request #1875 from giuseppe/path-exists

fileutils: new function to check for path existence

drivers/aufs/aufs.go

@@ -41,6 +41,7 @@ import (
 	"github.com/containers/storage/pkg/archive"
 	"github.com/containers/storage/pkg/chrootarchive"
 	"github.com/containers/storage/pkg/directory"
+	"github.com/containers/storage/pkg/fileutils"
 	"github.com/containers/storage/pkg/idtools"
 	"github.com/containers/storage/pkg/locker"
 	mountpk "github.com/containers/storage/pkg/mount"
@@ -243,7 +244,7 @@ func (a *Driver) Metadata(id string) (map[string]string, error) {
 // Exists returns true if the given id is registered with
 // this driver
 func (a *Driver) Exists(id string) bool {
-	if _, err := os.Lstat(path.Join(a.rootPath(), "layers", id)); err != nil {
+	if err := fileutils.Lexists(path.Join(a.rootPath(), "layers", id)); err != nil {
 		return false
 	}
 	return true
@@ -431,7 +432,7 @@ func atomicRemove(source string) error {
 	case err == nil, os.IsNotExist(err):
 	case os.IsExist(err):
 		// Got error saying the target dir already exists, maybe the source doesn't exist due to a previous (failed) remove
-		if _, e := os.Stat(source); !os.IsNotExist(e) {
+		if e := fileutils.Exists(source); !os.IsNotExist(e) {
 			return fmt.Errorf("target rename dir '%s' exists but should not, this needs to be manually cleaned up: %w", target, err)
 		}
 	default:

drivers/btrfs/btrfs.go

@@ -32,6 +32,7 @@ import (
 
 	graphdriver "github.com/containers/storage/drivers"
 	"github.com/containers/storage/pkg/directory"
+	"github.com/containers/storage/pkg/fileutils"
 	"github.com/containers/storage/pkg/idtools"
 	"github.com/containers/storage/pkg/mount"
 	"github.com/containers/storage/pkg/parsers"
@@ -589,11 +590,11 @@ func (d *Driver) setStorageSize(dir string, driver *Driver) error {
 // Remove the filesystem with given id.
 func (d *Driver) Remove(id string) error {
 	dir := d.subvolumesDirID(id)
-	if _, err := os.Stat(dir); err != nil {
+	if err := fileutils.Exists(dir); err != nil {
 		return err
 	}
 	quotasDir := d.quotasDirID(id)
-	if _, err := os.Stat(quotasDir); err == nil {
+	if err := fileutils.Exists(quotasDir); err == nil {
 		if err := os.Remove(quotasDir); err != nil {
 			return err
 		}
@@ -669,7 +670,7 @@ func (d *Driver) ReadWriteDiskUsage(id string) (*directory.DiskUsage, error) {
 // Exists checks if the id exists in the filesystem.
 func (d *Driver) Exists(id string) bool {
 	dir := d.subvolumesDirID(id)
-	_, err := os.Stat(dir)
+	err := fileutils.Exists(dir)
 	return err == nil
 }
 

drivers/devmapper/deviceset.go

@@ -22,6 +22,7 @@ import (
 	graphdriver "github.com/containers/storage/drivers"
 	"github.com/containers/storage/pkg/devicemapper"
 	"github.com/containers/storage/pkg/dmesg"
+	"github.com/containers/storage/pkg/fileutils"
 	"github.com/containers/storage/pkg/idtools"
 	"github.com/containers/storage/pkg/loopback"
 	"github.com/containers/storage/pkg/mount"
@@ -257,7 +258,7 @@ func (devices *DeviceSet) hasImage(name string) bool {
 	dirname := devices.loopbackDir()
 	filename := path.Join(dirname, name)
 
-	_, err := os.Stat(filename)
+	err := fileutils.Exists(filename)
 	return err == nil
 }
 
@@ -1192,7 +1193,7 @@ func (devices *DeviceSet) growFS(info *devInfo) error {
 	defer devices.deactivateDevice(info)
 
 	fsMountPoint := "/run/containers/storage/mnt"
-	if _, err := os.Stat(fsMountPoint); os.IsNotExist(err) {
+	if err := fileutils.Exists(fsMountPoint); os.IsNotExist(err) {
 		if err := os.MkdirAll(fsMountPoint, 0o700); err != nil {
 			return err
 		}

drivers/devmapper/driver.go

@@ -12,6 +12,7 @@ import (
 	graphdriver "github.com/containers/storage/drivers"
 	"github.com/containers/storage/pkg/devicemapper"
 	"github.com/containers/storage/pkg/directory"
+	"github.com/containers/storage/pkg/fileutils"
 	"github.com/containers/storage/pkg/idtools"
 	"github.com/containers/storage/pkg/locker"
 	"github.com/containers/storage/pkg/mount"
@@ -222,7 +223,7 @@ func (d *Driver) Get(id string, options graphdriver.MountOpts) (string, error) {
 	}
 
 	idFile := path.Join(mp, "id")
-	if _, err := os.Stat(idFile); err != nil && os.IsNotExist(err) {
+	if err := fileutils.Exists(idFile); err != nil && os.IsNotExist(err) {
 		// Create an "id" file with the container/image id in it to help reconstruct this in case
 		// of later problems
 		if err := os.WriteFile(idFile, []byte(id), 0o600); err != nil {

drivers/driver.go

@@ -10,6 +10,7 @@ import (
 
 	"github.com/containers/storage/pkg/archive"
 	"github.com/containers/storage/pkg/directory"
+	"github.com/containers/storage/pkg/fileutils"
 	"github.com/containers/storage/pkg/idtools"
 	digest "github.com/opencontainers/go-digest"
 	"github.com/sirupsen/logrus"
@@ -471,7 +472,7 @@ func ScanPriorDrivers(root string) map[string]bool {
 
 	for driver := range drivers {
 		p := filepath.Join(root, driver)
-		if _, err := os.Stat(p); err == nil {
+		if err := fileutils.Exists(p); err == nil {
 			driversMap[driver] = true
 		}
 	}

drivers/overlay/overlay.go

@@ -24,6 +24,7 @@ import (
 	"github.com/containers/storage/pkg/archive"
 	"github.com/containers/storage/pkg/chrootarchive"
 	"github.com/containers/storage/pkg/directory"
+	"github.com/containers/storage/pkg/fileutils"
 	"github.com/containers/storage/pkg/fsutils"
 	"github.com/containers/storage/pkg/idmap"
 	"github.com/containers/storage/pkg/idtools"
@@ -574,7 +575,7 @@ func parseOptions(options []string) (*overlayOptions, error) {
 		case "mount_program":
 			logrus.Debugf("overlay: mount_program=%s", val)
 			if val != "" {
-				_, err := os.Stat(val)
+				err := fileutils.Exists(val)
 				if err != nil {
 					return nil, fmt.Errorf("overlay: can't stat program %q: %w", val, err)
 				}
@@ -676,7 +677,7 @@ func SupportsNativeOverlay(home, runhome string) (bool, error) {
 	}
 
 	for _, dir := range []string{home, runhome} {
-		if _, err := os.Stat(dir); err != nil {
+		if err := fileutils.Exists(dir); err != nil {
 			_ = idtools.MkdirAllAs(dir, 0o700, 0, 0)
 		}
 	}
@@ -854,7 +855,7 @@ func (d *Driver) Status() [][2]string {
 // LowerDir, UpperDir, WorkDir and MergeDir used to store data.
 func (d *Driver) Metadata(id string) (map[string]string, error) {
 	dir := d.dir(id)
-	if _, err := os.Stat(dir); err != nil {
+	if err := fileutils.Exists(dir); err != nil {
 		return nil, err
 	}
 
@@ -1016,7 +1017,7 @@ func (d *Driver) create(id, parent string, opts *graphdriver.CreateOpts, readOnl
 		rootGID = int(st.GID())
 	}
 
-	if _, err := system.Lstat(dir); err == nil {
+	if err := fileutils.Lexists(dir); err == nil {
 		logrus.Warnf("Trying to create a layer %#v while directory %q already exists; removing it first", id, dir)
 		// Don’t just os.RemoveAll(dir) here; d.Remove also removes the link in linkDir,
 		// so that we can’t end up with two symlinks in linkDir pointing to the same layer.
@@ -1144,7 +1145,7 @@ func (d *Driver) getLower(parent string) (string, error) {
 	parentDir := d.dir(parent)
 
 	// Ensure parent exists
-	if _, err := os.Lstat(parentDir); err != nil {
+	if err := fileutils.Lexists(parentDir); err != nil {
 		return "", err
 	}
 
@@ -1197,10 +1198,10 @@ func (d *Driver) dir2(id string, useImageStore bool) (string, string, bool) {
 
 	newpath := path.Join(homedir, id)
 
-	if _, err := os.Stat(newpath); err != nil {
+	if err := fileutils.Exists(newpath); err != nil {
 		for _, p := range d.getAllImageStores() {
 			l := path.Join(p, d.name, id)
-			_, err = os.Stat(l)
+			err = fileutils.Exists(l)
 			if err == nil {
 				return l, homedir, true
 			}
@@ -1340,7 +1341,7 @@ func (d *Driver) recreateSymlinks() error {
 			linkPath := path.Join(d.home, linkDir, strings.Trim(string(data), "\n"))
 			// Check if the symlink exists, and if it doesn't, create it again with the
 			// name we got from the "link" file
-			_, err = os.Lstat(linkPath)
+			err = fileutils.Lexists(linkPath)
 			if err != nil && os.IsNotExist(err) {
 				if err := os.Symlink(path.Join("..", dir.Name(), "diff"), linkPath); err != nil {
 					errs = multierror.Append(errs, err)
@@ -1417,7 +1418,7 @@ func (d *Driver) Get(id string, options graphdriver.MountOpts) (string, error) {
 
 func (d *Driver) get(id string, disableShifting bool, options graphdriver.MountOpts) (_ string, retErr error) {
 	dir, _, inAdditionalStore := d.dir2(id, false)
-	if _, err := os.Stat(dir); err != nil {
+	if err := fileutils.Exists(dir); err != nil {
 		return "", err
 	}
 
@@ -1528,8 +1529,7 @@ func (d *Driver) get(id string, disableShifting bool, options graphdriver.MountO
 	composeFsLayersDir := filepath.Join(dir, "composefs-layers")
 	maybeAddComposefsMount := func(lowerID string, i int, readWrite bool) (string, error) {
 		composefsBlob := d.getComposefsData(lowerID)
-		_, err = os.Stat(composefsBlob)
-		if err != nil {
+		if err := fileutils.Exists(composefsBlob); err != nil {
 			if os.IsNotExist(err) {
 				return "", nil
 			}
@@ -1633,11 +1633,11 @@ func (d *Driver) get(id string, disableShifting bool, options graphdriver.MountO
 
 		absLowers = append(absLowers, lower)
 		diffN = 1
-		_, err = os.Stat(dumbJoin(lower, "..", nameWithSuffix("diff", diffN)))
+		err = fileutils.Exists(dumbJoin(lower, "..", nameWithSuffix("diff", diffN)))
 		for err == nil {
 			absLowers = append(absLowers, dumbJoin(lower, "..", nameWithSuffix("diff", diffN)))
 			diffN++
-			_, err = os.Stat(dumbJoin(lower, "..", nameWithSuffix("diff", diffN)))
+			err = fileutils.Exists(dumbJoin(lower, "..", nameWithSuffix("diff", diffN)))
 		}
 	}
 
@@ -1660,14 +1660,14 @@ func (d *Driver) get(id string, disableShifting bool, options graphdriver.MountO
 			return "", err
 		}
 		// if it is in an additional store, do not fail if the directory already exists
-		if _, err2 := os.Stat(diffDir); err2 != nil {
+		if err2 := fileutils.Exists(diffDir); err2 != nil {
 			return "", err
 		}
 	}
 
 	mergedDir := path.Join(dir, "merged")
 	// Attempt to create the merged dir only if it doesn't exist.
-	if _, err := os.Stat(mergedDir); err != nil && os.IsNotExist(err) {
+	if err := fileutils.Exists(mergedDir); err != nil && os.IsNotExist(err) {
 		if err := idtools.MkdirAs(mergedDir, 0o700, rootUID, rootGID); err != nil && !os.IsExist(err) {
 			return "", err
 		}
@@ -1836,22 +1836,22 @@ func (d *Driver) get(id string, disableShifting bool, options graphdriver.MountO
 // Put unmounts the mount path created for the give id.
 func (d *Driver) Put(id string) error {
 	dir, _, inAdditionalStore := d.dir2(id, false)
-	if _, err := os.Stat(dir); err != nil {
+	if err := fileutils.Exists(dir); err != nil {
 		return err
 	}
 	mountpoint := path.Join(dir, "merged")
 	if count := d.ctr.Decrement(mountpoint); count > 0 {
 		return nil
 	}
-	if _, err := os.ReadFile(path.Join(dir, lowerFile)); err != nil && !os.IsNotExist(err) {
+	if err := fileutils.Exists(path.Join(dir, lowerFile)); err != nil && !os.IsNotExist(err) {
 		return err
 	}
 
 	unmounted := false
 
 	mappedRoot := filepath.Join(d.home, id, "mapped")
 	// It should not happen, but cleanup any mapped mount if it was leaked.
-	if _, err := os.Stat(mappedRoot); err == nil {
+	if err := fileutils.Exists(mappedRoot); err == nil {
 		mounts, err := os.ReadDir(mappedRoot)
 		if err == nil {
 			// Go through all of the mapped mounts.
@@ -1922,7 +1922,7 @@ func (d *Driver) Put(id string) error {
 
 // Exists checks to see if the id is already mounted.
 func (d *Driver) Exists(id string) bool {
-	_, err := os.Stat(d.dir(id))
+	err := fileutils.Exists(d.dir(id))
 	return err == nil
 }
 
@@ -2334,7 +2334,7 @@ func (d *Driver) UpdateLayerIDMap(id string, toContainer, toHost *idtools.IDMapp
 	}
 	for err == nil {
 		i++
-		_, err = os.Stat(nameWithSuffix(diffDir, i))
+		err = fileutils.Exists(nameWithSuffix(diffDir, i))
 	}
 
 	for i > 0 {
@@ -2419,7 +2419,7 @@ func (d *Driver) getAdditionalLayerPath(dgst digest.Digest, ref string) (string,
 			filepath.Join(target, "info"),
 			filepath.Join(target, "blob"),
 		} {
-			if _, err := os.Stat(p); err != nil {
+			if err := fileutils.Exists(p); err != nil {
 				wrapped := fmt.Errorf("failed to stat additional layer %q: %w", p, err)
 				return "", fmt.Errorf("%v: %w", wrapped, graphdriver.ErrLayerUnknown)
 			}

drivers/vfs/driver.go

@@ -12,6 +12,7 @@ import (
 	graphdriver "github.com/containers/storage/drivers"
 	"github.com/containers/storage/pkg/archive"
 	"github.com/containers/storage/pkg/directory"
+	"github.com/containers/storage/pkg/fileutils"
 	"github.com/containers/storage/pkg/idtools"
 	"github.com/containers/storage/pkg/parsers"
 	"github.com/containers/storage/pkg/system"
@@ -210,7 +211,7 @@ func (d *Driver) dir2(id string, useImageStore bool) string {
 	} else {
 		homedir = filepath.Join(d.home, "dir", filepath.Base(id))
 	}
-	if _, err := os.Stat(homedir); err != nil {
+	if err := fileutils.Exists(homedir); err != nil {
 		additionalHomes := d.additionalHomes[:]
 		if d.imageStore != "" {
 			additionalHomes = append(additionalHomes, d.imageStore)
@@ -269,7 +270,7 @@ func (d *Driver) ReadWriteDiskUsage(id string) (*directory.DiskUsage, error) {
 
 // Exists checks to see if the directory exists for the given id.
 func (d *Driver) Exists(id string) bool {
-	_, err := os.Stat(d.dir(id))
+	err := fileutils.Exists(d.dir(id))
 	return err == nil
 }
 

drivers/windows/windows.go

@@ -26,6 +26,7 @@ import (
 	graphdriver "github.com/containers/storage/drivers"
 	"github.com/containers/storage/pkg/archive"
 	"github.com/containers/storage/pkg/directory"
+	"github.com/containers/storage/pkg/fileutils"
 	"github.com/containers/storage/pkg/idtools"
 	"github.com/containers/storage/pkg/ioutils"
 	"github.com/containers/storage/pkg/longpath"
@@ -231,7 +232,7 @@ func (d *Driver) create(id, parent, mountLabel string, readOnly bool, storageOpt
 		if err != nil {
 			return err
 		}
-		if _, err := os.Stat(filepath.Join(parentPath, "Files")); err == nil {
+		if err := fileutils.Exists(filepath.Join(parentPath, "Files")); err == nil {
 			// This is a legitimate parent layer (not the empty "-init" layer),
 			// so include it in the layer chain.
 			layerChain = []string{parentPath}
@@ -266,7 +267,7 @@ func (d *Driver) create(id, parent, mountLabel string, readOnly bool, storageOpt
 		}
 	}
 
-	if _, err := os.Lstat(d.dir(parent)); err != nil {
+	if err := fileutils.Lexists(d.dir(parent)); err != nil {
 		if err2 := hcsshim.DestroyLayer(d.info, id); err2 != nil {
 			logrus.Warnf("Failed to DestroyLayer %s: %s", id, err2)
 		}

pkg/archive/archive.go

@@ -1023,7 +1023,7 @@ loop:
 			// Not the root directory, ensure that the parent directory exists
 			parent := filepath.Dir(hdr.Name)
 			parentPath := filepath.Join(dest, parent)
-			if _, err := os.Lstat(parentPath); err != nil && os.IsNotExist(err) {
+			if err := fileutils.Lexists(parentPath); err != nil && os.IsNotExist(err) {
 				err = idtools.MkdirAllAndChownNew(parentPath, 0o777, rootIDs)
 				if err != nil {
 					return err

pkg/archive/changes.go

@@ -13,6 +13,7 @@ import (
 	"syscall"
 	"time"
 
+	"github.com/containers/storage/pkg/fileutils"
 	"github.com/containers/storage/pkg/idtools"
 	"github.com/containers/storage/pkg/pools"
 	"github.com/containers/storage/pkg/system"
@@ -106,7 +107,7 @@ func aufsDeletedFile(root, path string, fi os.FileInfo) (string, error) {
 
 func aufsWhiteoutPresent(root, path string) (bool, error) {
 	f := filepath.Join(filepath.Dir(path), WhiteoutPrefix+filepath.Base(path))
-	_, err := os.Stat(filepath.Join(root, f))
+	err := fileutils.Exists(filepath.Join(root, f))
 	if err == nil {
 		return true, nil
 	}

pkg/archive/copy.go

@@ -8,6 +8,7 @@ import (
 	"path/filepath"
 	"strings"
 
+	"github.com/containers/storage/pkg/fileutils"
 	"github.com/sirupsen/logrus"
 )
 
@@ -94,7 +95,7 @@ func TarResource(sourceInfo CopyInfo) (content io.ReadCloser, err error) {
 // items in the resulting tar archive to match the given rebaseName if not "".
 func TarResourceRebase(sourcePath, rebaseName string) (content io.ReadCloser, err error) {
 	sourcePath = normalizePath(sourcePath)
-	if _, err = os.Lstat(sourcePath); err != nil {
+	if err = fileutils.Lexists(sourcePath); err != nil {
 		// Catches the case where the source does not exist or is not a
 		// directory if asserted to be a directory, as this also causes an
 		// error.