vendor: vendor fscrypt integration dependencies

Signed-off-by: Marcel Lauhoff <marcel.lauhoff@suse.com>

vendor/github.com/google/fscrypt/filesystem/path.go

@@ -0,0 +1,128 @@
+/*
+ * path.go - Utility functions for dealing with filesystem paths
+ *
+ * Copyright 2017 Google Inc.
+ * Author: Joe Richey (joerichey@google.com)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy of
+ * the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations under
+ * the License.
+ */
+
+package filesystem
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"path/filepath"
+
+	"golang.org/x/sys/unix"
+
+	"github.com/pkg/errors"
+)
+
+// OpenFileOverridingUmask calls os.OpenFile but with the umask overridden so
+// that no permission bits are masked out if the file is created.
+func OpenFileOverridingUmask(name string, flag int, perm os.FileMode) (*os.File, error) {
+	oldMask := unix.Umask(0)
+	defer unix.Umask(oldMask)
+	return os.OpenFile(name, flag, perm)
+}
+
+// canonicalizePath turns path into an absolute path without symlinks.
+func canonicalizePath(path string) (string, error) {
+	path, err := filepath.Abs(path)
+	if err != nil {
+		return "", err
+	}
+	path, err = filepath.EvalSymlinks(path)
+
+	// Get a better error if we have an invalid path
+	if pathErr, ok := err.(*os.PathError); ok {
+		err = errors.Wrap(pathErr.Err, pathErr.Path)
+	}
+
+	return path, err
+}
+
+// loggedStat runs os.Stat, but it logs the error if stat returns any error
+// other than nil or IsNotExist.
+func loggedStat(name string) (os.FileInfo, error) {
+	info, err := os.Stat(name)
+	if err != nil && !os.IsNotExist(err) {
+		log.Print(err)
+	}
+	return info, err
+}
+
+// loggedLstat runs os.Lstat (doesn't dereference trailing symlink), but it logs
+// the error if lstat returns any error other than nil or IsNotExist.
+func loggedLstat(name string) (os.FileInfo, error) {
+	info, err := os.Lstat(name)
+	if err != nil && !os.IsNotExist(err) {
+		log.Print(err)
+	}
+	return info, err
+}
+
+// isDir returns true if the path exists and is that of a directory.
+func isDir(path string) bool {
+	info, err := loggedStat(path)
+	return err == nil && info.IsDir()
+}
+
+// isRegularFile returns true if the path exists and is that of a regular file.
+func isRegularFile(path string) bool {
+	info, err := loggedStat(path)
+	return err == nil && info.Mode().IsRegular()
+}
+
+// HaveReadAccessTo returns true if the process has read access to a file or
+// directory, without actually opening it.
+func HaveReadAccessTo(path string) bool {
+	return unix.Access(path, unix.R_OK) == nil
+}
+
+// DeviceNumber represents a combined major:minor device number.
+type DeviceNumber uint64
+
+func (num DeviceNumber) String() string {
+	return fmt.Sprintf("%d:%d", unix.Major(uint64(num)), unix.Minor(uint64(num)))
+}
+
+func newDeviceNumberFromString(str string) (DeviceNumber, error) {
+	var major, minor uint32
+	if count, _ := fmt.Sscanf(str, "%d:%d", &major, &minor); count != 2 {
+		return 0, errors.Errorf("invalid device number string %q", str)
+	}
+	return DeviceNumber(unix.Mkdev(major, minor)), nil
+}
+
+// getDeviceNumber returns the device number of the device node at the given
+// path.  If there is a symlink at the path, it is dereferenced.
+func getDeviceNumber(path string) (DeviceNumber, error) {
+	var stat unix.Stat_t
+	if err := unix.Stat(path, &stat); err != nil {
+		return 0, err
+	}
+	return DeviceNumber(stat.Rdev), nil
+}
+
+// getNumberOfContainingDevice returns the device number of the filesystem which
+// contains the given file.  If the file is a symlink, it is not dereferenced.
+func getNumberOfContainingDevice(path string) (DeviceNumber, error) {
+	var stat unix.Stat_t
+	if err := unix.Lstat(path, &stat); err != nil {
+		return 0, err
+	}
+	return DeviceNumber(stat.Dev), nil
+}