test: utility to create files with a specific gfid

python test utility that uses setxattr() interface to
create files with a predefined gfid (which is also used
by geo-replication). this utility aids in writing test
cases for gfid-access translator.

Change-Id: Ib11248844a094cc02dae74d969f2e9212f94ede4
BUG: 1111490
Signed-off-by: Venky Shankar <vshankar@redhat.com>
Reviewed-on: http://review.gluster.org/8275
Reviewed-by: Aravinda VK <avishwan@redhat.com>
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>

1 files changed, 94 insertions, 0 deletions

diff --git a/tests/utils/libcxattr.py b/tests/utils/libcxattr.py
new file mode 100644
index 00000000000..74d120fa196
--- /dev/null
+++ b/tests/utils/libcxattr.py
@@ -0,0 +1,94 @@
+#
+# Copyright (c) 2011-2014 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.
+#
+
+import os
+from ctypes import CDLL, c_int, create_string_buffer
+from ctypes.util import find_library
+
+
+class Xattr(object):
+
+    """singleton that wraps the extended attribues system
+       interface for python using ctypes
+
+       Just implement it to the degree we need it, in particular
+       - we need just the l*xattr variants, ie. we never want symlinks to be
+         followed
+       - don't need size discovery for getxattr, as we always know the exact
+         sizes we expect
+    """
+
+    libc = CDLL(find_library("libc"))
+
+    @classmethod
+    def geterrno(cls):
+        return c_int.in_dll(cls.libc, 'errno').value
+
+    @classmethod
+    def raise_oserr(cls):
+        errn = cls.geterrno()
+        raise OSError(errn, os.strerror(errn))
+
+    @classmethod
+    def _query_xattr(cls, path, siz, syscall, *a):
+        if siz:
+            buf = create_string_buffer('\0' * siz)
+        else:
+            buf = None
+        ret = getattr(cls.libc, syscall)(*((path,) + a + (buf, siz)))
+        if ret == -1:
+            cls.raise_oserr()
+        if siz:
+            return buf.raw[:ret]
+        else:
+            return ret
+
+    @classmethod
+    def lgetxattr(cls, path, attr, siz=0):
+        return cls._query_xattr(path, siz, 'lgetxattr', attr)
+
+    @classmethod
+    def lgetxattr_buf(cls, path, attr):
+        """lgetxattr variant with size discovery"""
+        size = cls.lgetxattr(path, attr)
+        if size == -1:
+            cls.raise_oserr()
+        if size == 0:
+            return ''
+        return cls.lgetxattr(path, attr, size)
+
+    @classmethod
+    def llistxattr(cls, path, siz=0):
+        ret = cls._query_xattr(path, siz, 'llistxattr')
+        if isinstance(ret, str):
+            ret = ret.split('\0')
+        return ret
+
+    @classmethod
+    def lsetxattr(cls, path, attr, val):
+        ret = cls.libc.lsetxattr(path, attr, val, len(val), 0)
+        if ret == -1:
+            cls.raise_oserr()
+
+    @classmethod
+    def lremovexattr(cls, path, attr):
+        ret = cls.libc.lremovexattr(path, attr)
+        if ret == -1:
+            cls.raise_oserr()
+
+    @classmethod
+    def llistxattr_buf(cls, path):
+        """listxattr variant with size discovery"""
+        size = cls.llistxattr(path)
+        if size == -1:
+            cls.raise_oserr()
+        if size == 0:
+            return []
+        return cls.llistxattr(path, size)