restore_set_root should check if it can read a directory before trying

to list the contents. Closes Savannah bug #21106


git-svn-id: http://svn.savannah.nongnu.org/svn/rdiff-backup@854 2b77aa54-bcbc-44c9-a7ec-4f6cf2b41109

trunk/rdiff-backup/CHANGELOG

 New in v1.1.15 (????/??/??)
 ---------------------------
 
+restore_set_root should check if it can read a particular directory
+before checking if "rdiff-backup-data" is contained in it. Closes
+Savannah bug #21106. (Patch from Alex Chapman)
+
 Regress.restore_orig_regfile should check if directories can be fsync'd
 before doing so. Fixes Savannah bug #21546. (Patch from Marc Horowitz)
 

trunk/rdiff-backup/rdiff_backup/Main.py

@@ -598,7 +598,7 @@ def restore_set_root(rpin):
 	i = len(pathcomps)
 	while i >= min_len_pathcomps:
 		parent_dir = rpath.RPath(rpin.conn, "/".join(pathcomps[:i]))
-		if (parent_dir.isdir() and
+		if (parent_dir.isdir() and parent_dir.is_readable() and
 			"rdiff-backup-data" in parent_dir.listdir()): break
 		if parent_dir.path == rpin.conn.Globals.get('restrict_path'):
 			return None

trunk/rdiff-backup/rdiff_backup/rpath.py

@@ -599,6 +599,10 @@ class RORPath:
 		"""Signal that rorp is a signature/diff for a hardlink file"""
 		self.data['linked'] = index
 
+	def is_readable(self):
+		"""Check whether user can read the file or directory"""
+		return self.conn.os.access(self.path, self.conn.os.R_OK)
+
 	def open(self, mode):
 		"""Return file type object if any was given using self.setfile"""
 		if mode != "rb": raise RPathException("Bad mode %s" % mode)