From 4af97584e2401ec114fbbd846a46700613d50a15 Mon Sep 17 00:00:00 2001
From: Evan Broder <broder@mit.edu>
Date: Tue, 20 Oct 2009 17:39:49 -0400
Subject: [PATCH] Add implementations of kname_parse and kname_unparse to
 afs._pts.

Signed-off-by: Evan Broder <broder@mit.edu>
---
 afs/_pts.pyx |   25 ++++++++++++++++++++++++-
 1 file changed, 24 insertions(+), 1 deletion(-)

diff --git a/afs/_pts.pyx b/afs/_pts.pyx
index 107bf85..2ebc064 100644
--- a/afs/_pts.pyx
+++ b/afs/_pts.pyx
@@ -1,5 +1,6 @@
 from afs cimport *
 from afs import pyafs_error
+import re
 
 cdef import from "afs/ptuser.h":
     enum:
@@ -77,7 +78,7 @@ cdef import from "krb5/krb5.h":
     struct krb5_principal_data:
         pass
 
-    ctypedef _krb5_context krb5_context
+    ctypedef _krb5_context * krb5_context
     ctypedef krb5_principal_data * krb5_principal
 
     ctypedef long krb5_int32
@@ -138,6 +139,28 @@ cdef int _ptentry_to_c(prcheckentry * c_entry, PTEntry p_entry) except -1:
     strncpy(c_entry.name, p_entry.name, sizeof(c_entry.name))
     return 0
 
+cdef object kname_re = re.compile(r'^([^.].*?)(?<!\\)(?:\.(.*?))?(?<!\\)@([^@]*)$')
+
+cdef object kname_parse(fullname):
+    """Parse a krb4-style principal into a name, instance, and realm."""
+    cdef object re_match = kname_re.match(fullname)
+    if not re_match:
+        return None
+    else:
+        princ = re_match.groups()
+        return tuple([re.sub(r'\\(.)', r'\1', x) if x else x for x in princ])
+
+cdef object kname_unparse(name, inst, realm):
+    """Unparse a name, instance, and realm into a single krb4
+    principal string."""
+    name = re.sub('r([.\\@])', r'\\\1', name)
+    inst = re.sub('r([.\\@])', r'\\\1', inst)
+    realm = re.sub(r'([\\@])', r'\\\1', realm)
+    if inst:
+        return '%s.%s@%s' % (name, inst, realm)
+    else:
+        return '%s@%s' % (name, realm)
+
 cdef class PTS:
     """
     A PTS object is essentially a handle to talk to the server in a
-- 
1.7.9.5