Add python bindings for murmurhash3

2 files changed, 165 insertions, 0 deletions

diff --git a/src/python/pysss_murmur.c b/src/python/pysss_murmur.c
new file mode 100644
index 000000000..1e89681c8
--- /dev/null
+++ b/src/python/pysss_murmur.c
@@ -0,0 +1,65 @@
+/*
+    Authors:
+        Sumit Bose <sbose@redhat.com>
+
+    Copyright (C) 2012 Red Hat
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <Python.h>
+
+#include "util/murmurhash3.h"
+
+PyDoc_STRVAR(murmurhash3_doc,
+"murmurhash3(key, key_len, seed) -> 32bit integer hash\n\
+\n\
+Calculate the murmur hash version 3 of the first key_len bytes from key\n\
+using the given seed."
+);
+
+static PyObject * py_murmurhash3(PyObject *module, PyObject *args)
+{
+    const char *key;
+    long key_len;
+    long long seed;
+    uint32_t hash;
+
+    if (!PyArg_ParseTuple(args, "slL", &key, &key_len, &seed)) {
+        PyErr_Format(PyExc_ValueError, "Invalid argument\n");
+        return NULL;
+    }
+
+    if (seed > UINT32_MAX || key_len > INT_MAX || key_len < 0 ||
+        key_len > strlen(key)) {
+        PyErr_Format(PyExc_ValueError, "Invalid value\n");
+        return NULL;
+    }
+
+    hash = murmurhash3(key, key_len, seed);
+
+    return PyLong_FromUnsignedLong((unsigned long) hash);
+}
+
+static PyMethodDef methods[] = {
+    {"murmurhash3", (PyCFunction) py_murmurhash3, METH_VARARGS, murmurhash3_doc},
+    {NULL,NULL, 0, NULL}
+};
+
+
+PyMODINIT_FUNC
+initpysss_murmur(void)
+{
+    Py_InitModule3("pysss_murmur", methods, "murmur hash functions");
+}
diff --git a/src/tests/pysss_murmur-test.py b/src/tests/pysss_murmur-test.py
new file mode 100755
index 000000000..715ea16b3
--- /dev/null
+++ b/src/tests/pysss_murmur-test.py
@@ -0,0 +1,100 @@
+#!/usr/bin/python
+#  SSSD
+#
+#  Unit tests for pysss_murmur
+#
+#  Copyright (C) Sumit Bose <sbose@redhat.com>        2012
+#
+#  This program is free software; you can redistribute it and/or modify
+#  it under the terms of the GNU General Public License as published by
+#  the Free Software Foundation; either version 3 of the License, or
+#  (at your option) any later version.
+#
+#  This program is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  GNU General Public License for more details.
+#
+#  You should have received a copy of the GNU General Public License
+#  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import unittest
+import sys
+import os
+import copy
+
+srcdir = os.getenv('builddir')
+if not srcdir:
+    srcdir = "."
+MODPATH = srcdir + "/.libs" #FIXME - is there a way to get this from libtool?
+
+def compat_assertItemsEqual(this, expected_seq, actual_seq, msg=None):
+    return this.assertEqual(sorted(expected_seq), sorted(actual_seq))
+
+def compat_assertIsInstance(this, obj, cls, msg=None):
+    return this.assertTrue(isinstance(obj, cls))
+
+# add compat methods for old unittest.TestCase versions
+# (python < 2.7, RHEL5 for instance)
+if not hasattr(unittest.TestCase, "assertItemsEqual"):
+    setattr(unittest.TestCase, "assertItemsEqual", compat_assertItemsEqual)
+if not hasattr(unittest.TestCase, "assertIsInstance"):
+    setattr(unittest.TestCase, "assertIsInstance", compat_assertIsInstance)
+
+class PySssMurmurImport(unittest.TestCase):
+    def setUp(self):
+        " Make sure we load the in-tree module "
+        self.system_path = sys.path[:]
+        sys.path = [ MODPATH ]
+
+    def tearDown(self):
+        " Restore the system path "
+        sys.path = self.system_path
+
+    def testImport(self):
+        " Import the module and assert it comes from tree "
+        try:
+            import pysss_murmur
+        except ImportError, e:
+            print >>sys.stderr, "Could not load the pysss_murmur module. Please check if it is compiled"
+            raise e
+        self.assertEqual(pysss_murmur.__file__, MODPATH + "/pysss_murmur.so")
+
+class PySssMurmurTest(unittest.TestCase):
+    def testExpectedHash(self):
+        hash = pysss_murmur.murmurhash3("S-1-5-21-2153326666-2176343378-3404031434", 41, 0xdeadbeef)
+        self.assertEqual(hash, 93103853)
+
+    def testInvalidArguments(self):
+        self.assertRaises(ValueError, pysss_murmur.murmurhash3, 1, 2, 3)
+        self.assertRaises(ValueError, pysss_murmur.murmurhash3, "test", 2)
+        self.assertRaises(ValueError, pysss_murmur.murmurhash3, "test")
+        self.assertRaises(ValueError, pysss_murmur.murmurhash3)
+        self.assertRaises(ValueError, pysss_murmur.murmurhash3, "test", -1, 3)
+        self.assertRaises(ValueError, pysss_murmur.murmurhash3, "test", 2,
+                          0xffffffffff)
+        self.assertRaises(ValueError, pysss_murmur.murmurhash3, "test",
+                          0xffffffffff, 3)
+
+
+if __name__ == "__main__":
+    error = 0
+
+    suite = unittest.TestLoader().loadTestsFromTestCase(PySssMurmurImport)
+    res = unittest.TextTestRunner().run(suite)
+    if not res.wasSuccessful():
+        error |= 0x1
+        # need to bail out here because pysss_murmur could not be imported
+        sys.exit(error)
+
+    # import the pysss_murmur module into the global namespace, but make sure
+    # it's the one in tree
+    sys.path.insert(0, MODPATH)
+    import pysss_murmur
+
+    suite = unittest.TestLoader().loadTestsFromTestCase(PySssMurmurTest)
+    res = unittest.TextTestRunner().run(suite)
+    if not res.wasSuccessful():
+        error |= 0x2
+
+    sys.exit(error)