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-rw-r--r--geo-replication/syncdaemon/libcxattr.py112
1 files changed, 112 insertions, 0 deletions
diff --git a/geo-replication/syncdaemon/libcxattr.py b/geo-replication/syncdaemon/libcxattr.py
new file mode 100644
index 00000000000..e6406c36bd7
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+++ b/geo-replication/syncdaemon/libcxattr.py
@@ -0,0 +1,112 @@
+#
+# 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, get_errno
+from py2py3 import (bytearray_to_str, gr_create_string_buffer,
+ gr_query_xattr, gr_lsetxattr, gr_lremovexattr)
+
+
+class Xattr(object):
+
+ """singleton that wraps the extended attributes 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("libc.so.6", use_errno=True)
+
+ @classmethod
+ def geterrno(cls):
+ return get_errno()
+
+ @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 = gr_create_string_buffer(siz)
+ else:
+ buf = None
+ ret = getattr(cls.libc, syscall)(*((path,) + a + (buf, siz)))
+ if ret == -1:
+ cls.raise_oserr()
+ if siz:
+ # py2 and py3 compatibility. Convert bytes array
+ # to string
+ result = bytearray_to_str(buf.raw)
+ return result[:ret]
+ else:
+ return ret
+
+ @classmethod
+ def lgetxattr(cls, path, attr, siz=0):
+ return gr_query_xattr(cls, 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 = gr_query_xattr(cls, path, siz, 'llistxattr')
+ if isinstance(ret, str):
+ ret = ret.strip('\0')
+ ret = ret.split('\0') if ret else []
+ return ret
+
+ @classmethod
+ def lsetxattr(cls, path, attr, val):
+ ret = gr_lsetxattr(cls, path, attr, val)
+ if ret == -1:
+ cls.raise_oserr()
+
+ @classmethod
+ def lremovexattr(cls, path, attr):
+ ret = gr_lremovexattr(cls, path, attr)
+ if ret == -1:
+ cls.raise_oserr()
+
+ @classmethod
+ def llistxattr_buf(cls, path):
+ """listxattr variant with size discovery"""
+ try:
+ # Assuming no more than 100 xattrs in a file/directory and
+ # each xattr key length will be less than 256 bytes
+ # llistxattr will be called with bigger size so that
+ # listxattr will not fail with ERANGE. OSError will be
+ # raised if fails even with the large size specified.
+ size = 256 * 100
+ return cls.llistxattr(path, size)
+ except OSError:
+ # If fixed length failed for getting list of xattrs then
+ # use the llistxattr call to get the size and use that
+ # size to get the list of xattrs.
+ size = cls.llistxattr(path)
+ if size == -1:
+ cls.raise_oserr()
+ if size == 0:
+ return []
+
+ return cls.llistxattr(path, size)