2010-07-02  Miloslav Trma─Ź  <mitr@redhat.com>

	* python/libusermodule.c (libuser_validate_id_value): New function.
	(libuser_methods): Add validateIdValue.
	* python/modules.txt (libuser): Document validateIdValue.
	* tests/files_test.py (Tests.testValidateIdValue): New test.

	* python/libusermodule.c (initlibuser): Provide VALUE_INVALID_ID.
	* python/modules.txt (libuser): Document VALUE_INVALID_ID.

diff -u b/python/libusermodule.c b/python/libusermodule.c
--- b/python/libusermodule.c	Fri Jul 02 17:38:47 2010 +0200
+++ b/python/libusermodule.c	Fri Jul 02 18:35:45 2010 +0200
@@ -58,6 +58,36 @@
 	return ret;
 }
 
+static PyObject *
+libuser_validate_id_value(PyObject *self, PyObject *value)
+{
+	PY_LONG_LONG ll;
+
+	DEBUG_ENTRY;
+	ll = PyLong_AsLongLong(value);
+	if (PyErr_Occurred())
+		goto error;
+
+	if ((id_t)ll != ll) {
+		PyErr_SetString(PyExc_OverflowError, _("Value out of range"));
+		goto error;
+	}
+	if (ll < 0) {
+		PyErr_SetString(PyExc_ValueError, _("ID must not be negative"));
+		goto error;
+	}
+	if (ll == LU_VALUE_INVALID_ID) {
+		PyErr_SetString(PyExc_ValueError, _("Invalid ID value"));
+		goto error;
+	}
+	DEBUG_EXIT;
+	Py_RETURN_NONE;
+
+error:
+	DEBUG_EXIT;
+	return NULL;
+}
+
 static PyMethodDef libuser_methods[] = {
 	{"admin", (PyCFunction) libuser_admin_new, METH_VARARGS | METH_KEYWORDS,
 	 "create a new administration context"},
@@ -71,6 +101,8 @@
 	 "create and return a new prompt record"},
 	{"getUserShells", libuser_get_user_shells, METH_NOARGS,
 	 "return a list of valid shells"},
+	{"validateIdValue", libuser_validate_id_value, METH_O,
+	 "validate an id_t value"},
 	{NULL, NULL, 0, NULL},
 };
 
@@ -145,6 +177,8 @@
 
 	/* Miscellaneous. */
 	PyDict_SetItemString(dict, "UT_NAMESIZE", PyInt_FromLong(UT_NAMESIZE));
+	PyDict_SetItemString(dict, "VALUE_INVALID_ID",
+			     PyLong_FromLongLong(LU_VALUE_INVALID_ID));
 
 	DEBUG_EXIT;
 }
diff -u b/python/modules.txt b/python/modules.txt
--- b/python/modules.txt	Fri Jul 02 17:38:47 2010 +0200
+++ b/python/modules.txt	Fri Jul 02 18:35:45 2010 +0200
@@ -28,6 +28,7 @@
         	- SHADOWWARNING
 
 		- UT_NAMESIZE
+		- VALUE_INVALID_ID
 
 	Methods:
 		- getUserShells: Returns a list of valid shells for users on
@@ -48,6 +49,10 @@
 			Arguments:
 				None.
 			Returns: a libuser.Prompt object.
+		- validateIdValue: Verifies an id_t value is in the valid range.
+			Arguments:
+				id_t integer value
+			Returns: None.  Raises an exception on error.
 	Types:
 		- Admin - An administrative context.
 			Methods:
--- a/tests/files_test.py	Fri Jul 02 17:38:47 2010 +0200
+++ b/tests/files_test.py	Fri Jul 02 18:35:45 2010 +0200
@@ -1229,6 +1229,26 @@
         self.a.addGroup(e)
         self.assertEqual(self.a.enumerateGroupsFull('group31_3:*'), [])
 
+    # ValidateIdValue is unrelated to the files module.
+    def testValidateIdValue(self):
+        libuser.validateIdValue(0)
+        libuser.validateIdValue(1)
+        libuser.validateIdValue(500)
+        libuser.validateIdValue(500L)
+        self.assertRaises(TypeError, libuser.validateIdValue, 'abc')
+        # OverflowError if id_t is signed, ValueError otherwise
+        self.assertRaises((ValueError, OverflowError), libuser.validateIdValue,
+                          -1)
+        self.assertRaises((ValueError, OverflowError), libuser.validateIdValue,
+                          -2)
+        self.assertRaises(ValueError, libuser.validateIdValue,
+                          libuser.VALUE_INVALID_ID)
+        if libuser.VALUE_INVALID_ID > 0:
+            libuser.validateIdValue(libuser.VALUE_INVALID_ID - 1)
+            if libuser.VALUE_INVALID_ID < 2 ** 64 - 1:
+                self.assertRaises(OverflowError, libuser.validateIdValue,
+                                  2 ** 64 - 1)
+
     def tearDown(self):
         del self.a