georep: python2 to python3 compat - syscalls

1. ctypes/syscalls
    A) arguments is expected to be encoded
    B) Raw conversion of return value from bytearray into string
2. struct pack/unpack - Raw converstion of string to bytearray
3. basestring -> str

Updates: #411
Change-Id: I80f939adcdec0ed0022c87c0b76d057ad5559e5a
Signed-off-by: Kotresh HR <khiremat@redhat.com>

1 files changed, 49 insertions, 0 deletions

diff --git a/geo-replication/syncdaemon/py2py3.py b/geo-replication/syncdaemon/py2py3.py
new file mode 100644
index 00000000000..4c0e1152aa8
--- /dev/null
+++ b/geo-replication/syncdaemon/py2py3.py
@@ -0,0 +1,49 @@
+#
+# Copyright (c) 2018 Red Hat, Inc. <http://www.redhat.com>
+# This file is part of GlusterFS.
+
+# This file is licensed to you under your choice of the GNU Lesser
+# General Public License, version 3 or any later version (LGPLv3 or
+# later), or the GNU General Public License, version 2 (GPLv2), in all
+# cases as published by the Free Software Foundation.
+#
+
+# All python2/python3 compatibility routines
+
+import sys
+import os
+
+
+if sys.version_info >= (3,):
+    def pipe():
+        (r, w) = os.pipe()
+        os.set_inheritable(r, True)
+        os.set_inheritable(w, True)
+        return (r, w)
+
+    # Raw conversion of bytearray to string. Used in the cases where
+    # buffer is created by create_string_buffer which is a 8-bit char
+    # array and passed to syscalls to fetch results. Using encode/decode
+    # doesn't work as it converts to string altering the size.
+    def bytearray_to_str(byte_arr):
+        return ''.join([chr(b) for b in byte_arr])
+
+    # Raw conversion of string to bytes. This is required to convert
+    # back the string into bytearray(c char array) to use in struc
+    # pack/unpacking. Again encode/decode can't be used as it
+    # converts it alters size.
+    def str_to_bytearray(string):
+        return bytes([ord(c) for c in string])
+
+else:
+    def pipe():
+        (r, w) = os.pipe()
+        return (r, w)
+
+    # Raw conversion of bytearray to string
+    def bytearray_to_str(byte_arr):
+        return ''.join([b for b in byte_arr])
+
+    # Raw conversion of string to bytearray
+    def str_to_bytearray(string):
+        return b"".join([c for c in string])