Update dependencies, enable pruning for vendor/

So, `dep` got an nice new feature to remove tests and non-go files from
`vendor/`, and this brings the size of the vendor directory from ~300MiB
down to ~20MiB. We don that now.

vendor/github.com/pkg/xattr/xattr_linux.go

@@ -2,70 +2,63 @@
 
 package xattr
 
-import "syscall"
+import (
+	"syscall"
 
-// Get retrieves extended attribute data associated with path.
-func Get(path, name string) ([]byte, error) {
-	// find size.
-	size, err := syscall.Getxattr(path, name, nil)
-	if err != nil {
-		return nil, &Error{"xattr.Get", path, name, err}
-	}
-	if size > 0 {
-		data := make([]byte, size)
-		// Read into buffer of that size.
-		read, err := syscall.Getxattr(path, name, data)
-		if err != nil {
-			return nil, &Error{"xattr.Get", path, name, err}
+	"golang.org/x/sys/unix"
+)
+
+const (
+	XATTR_CREATE  = unix.XATTR_CREATE
+	XATTR_REPLACE = unix.XATTR_REPLACE
+
+	// ENOATTR is not exported by the syscall package on Linux, because it is
+	// an alias for ENODATA. We export it here so it is available on all
+	// our supported platforms.
+	ENOATTR = syscall.ENODATA
+)
+
+func getxattr(path string, name string, data []byte) (int, error) {
+	return unix.Getxattr(path, name, data)
+}
+
+func lgetxattr(path string, name string, data []byte) (int, error) {
+	return unix.Lgetxattr(path, name, data)
+}
+
+func setxattr(path string, name string, data []byte, flags int) error {
+	return unix.Setxattr(path, name, data, flags)
+}
+
+func lsetxattr(path string, name string, data []byte, flags int) error {
+	return unix.Lsetxattr(path, name, data, flags)
+}
+
+func removexattr(path string, name string) error {
+	return unix.Removexattr(path, name)
+}
+
+func lremovexattr(path string, name string) error {
+	return unix.Lremovexattr(path, name)
+}
+
+func listxattr(path string, data []byte) (int, error) {
+	return unix.Listxattr(path, data)
+}
+
+func llistxattr(path string, data []byte) (int, error) {
+	return unix.Llistxattr(path, data)
+}
+
+// stringsFromByteSlice converts a sequence of attributes to a []string.
+// On Darwin and Linux, each entry is a NULL-terminated string.
+func stringsFromByteSlice(buf []byte) (result []string) {
+	offset := 0
+	for index, b := range buf {
+		if b == 0 {
+			result = append(result, string(buf[offset:index]))
+			offset = index + 1
 		}
-		return data[:read], nil
 	}
-	return []byte{}, nil
-}
-
-// List retrieves a list of names of extended attributes associated
-// with the given path in the file system.
-func List(path string) ([]string, error) {
-	// find size.
-	size, err := syscall.Listxattr(path, nil)
-	if err != nil {
-		return nil, &Error{"xattr.List", path, "", err}
-	}
-	if size > 0 {
-		// `size + 1` because of ERANGE error when reading
-		// from a SMB1 mount point (https://github.com/pkg/xattr/issues/16).
-		buf := make([]byte, size+1)
-		// Read into buffer of that size.
-		read, err := syscall.Listxattr(path, buf)
-		if err != nil {
-			return nil, &Error{"xattr.List", path, "", err}
-		}
-		return nullTermToStrings(buf[:read]), nil
-	}
-	return []string{}, nil
-}
-
-// Set associates name and data together as an attribute of path.
-func Set(path, name string, data []byte) error {
-	if err := syscall.Setxattr(path, name, data, 0); err != nil {
-		return &Error{"xattr.Set", path, name, err}
-	}
-	return nil
-}
-
-// Remove removes the attribute associated
-// with the given path.
-func Remove(path, name string) error {
-	if err := syscall.Removexattr(path, name); err != nil {
-		return &Error{"xattr.Remove", path, name, err}
-	}
-	return nil
-}
-
-// Supported checks if filesystem supports extended attributes
-func Supported(path string) bool {
-	if _, err := syscall.Listxattr(path, nil); err != nil {
-		return err != syscall.ENOTSUP
-	}
-	return true
+	return
 }