Python 3.6 invalid escape sequence deprecation fixes

https://docs.python.org/3/whatsnew/3.6.html#deprecated-python-behavior

A backslash-character pair that is not a valid escape sequence now
generates a DeprecationWarning. Although this will eventually become a
SyntaxError, that will not be for several Python releases.

The problem appears when you use '-W error':

$ python3 -W error -c 'import re; re.findall("[^a-zA-Z0-9_\-\.]", " *%$")'
  File "<string>", line 1
SyntaxError: invalid escape sequence \-

Signed-off-by: Ville Skyttä <ville.skytta@iki.fi>

[ Edited commit message as per suggestion from Petr Lautrbach ]
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>

python/semanage/seobject.py

@@ -192,8 +192,8 @@ class nulllogger:
 def validate_level(raw):
     sensitivity = "s[0-9]*"
     category = "c[0-9]*"
-    cat_range = category + "(\." + category + ")?"
-    categories = cat_range + "(\," + cat_range + ")*"
+    cat_range = category + r"(\." + category + ")?"
+    categories = cat_range + r"(\," + cat_range + ")*"
     reg = sensitivity + "(-" + sensitivity + ")?" + "(:" + categories + ")?"
     return re.search("^" + reg + "$", raw)
 

python/sepolgen/src/sepolgen/module.py

@@ -40,7 +40,7 @@ from . import defaults
 def is_valid_name(modname):
     """Check that a module name is valid.
     """
-    m = re.findall("[^a-zA-Z0-9_\-\.]", modname)
+    m = re.findall(r"[^a-zA-Z0-9_\-\.]", modname)
     if len(m) == 0 and modname[0].isalpha():
         return True
     else:

python/sepolicy/sepolicy/generate.py

@@ -1329,7 +1329,7 @@ allow %s_t %s_t:%s_socket name_%s;
             self.add_dir("/var/lib/%s" % self.name)
 
         if os.path.isfile("/etc/rc.d/init.d/%s" % self.name):
-            self.set_init_script("/etc/rc\.d/init\.d/%s" % self.name)
+            self.set_init_script(r"/etc/rc\.d/init\.d/%s" % self.name)
 
         # we don't want to have subdir in the .fc policy file
         # if we already specify labeling for parent dir