Backport ctypes.c_ssize_t support to py26

ctypes.c_ssize_t was introduced in Python 2.7
This made libgfapi-python bindings unusable in RHEL 6 which
only contains Python 2.6

Change-Id: I401697004d7eecb110b8c92a3ddd27397e3d8785
Signed-off-by: Prashanth Pai <ppai@redhat.com>

1 files changed, 13 insertions, 0 deletions

diff --git a/gluster/api.py b/gluster/api.py
index 62135c5..d2a0840 100755
--- a/gluster/api.py
+++ b/gluster/api.py
@@ -11,6 +11,7 @@
 
 import ctypes
 from ctypes.util import find_library
+from ctypes import sizeof
 
 
 # LD_LIBRARY_PATH is not looked up by ctypes.util.find_library()
@@ -41,6 +42,18 @@ except OSError:
     raise ImportError("ctypes.CDLL() cannot load {0}. You might want to set "
                       "LD_LIBRARY_PATH env variable".format(so_file_name))
 
+# c_ssize_t was only added in py27. Manually backporting it here for py26
+try:
+    import ctypes.c_ssize_t
+except ImportError:
+    if sizeof(ctypes.c_uint) == sizeof(ctypes.c_void_p):
+        setattr(ctypes, 'c_ssize_t', ctypes.c_int)
+    elif sizeof(ctypes.c_ulong) == sizeof(ctypes.c_void_p):
+        setattr(ctypes, 'c_ssize_t', ctypes.c_long)
+    elif sizeof(ctypes.c_ulonglong) == sizeof(ctypes.c_void_p):
+        setattr(ctypes, 'c_ssize_t', ctypes.c_longlong)
+
+
 # Wow, the Linux kernel folks really play nasty games with this structure.  If
 # you look at the man page for stat(2) and then at this definition you'll note
 # two discrepancies.  First, we seem to have st_nlink and st_mode reversed.  In