PL/Python: Fix crash when colnames() etc. called without result set

The result object methods colnames() etc. would crash when called
after a command that did not produce a result set.  Now they throw an
exception.

discovery and initial patch by Jean-Baptiste Quenot

1 files changed, 19 insertions, 0 deletions

diff --git a/src/pl/plpython/plpy_resultobject.c b/src/pl/plpython/plpy_resultobject.c
index b25e8083b9e..fcf8074228d 100644
--- a/src/pl/plpython/plpy_resultobject.c
+++ b/src/pl/plpython/plpy_resultobject.c
@@ -9,6 +9,7 @@
 #include "plpython.h"
 
 #include "plpy_resultobject.h"
+#include "plpy_elog.h"
 
 
 static void PLy_result_dealloc(PyObject *arg);
@@ -131,6 +132,12 @@ PLy_result_colnames(PyObject *self, PyObject *unused)
 	PyObject   *list;
 	int			i;
 
+	if (!ob->tupdesc)
+	{
+		PLy_exception_set(PLy_exc_error, "command did not produce a result set");
+		return NULL;
+	}
+
 	list = PyList_New(ob->tupdesc->natts);
 	for (i = 0; i < ob->tupdesc->natts; i++)
 		PyList_SET_ITEM(list, i, PyString_FromString(NameStr(ob->tupdesc->attrs[i]->attname)));
@@ -145,6 +152,12 @@ PLy_result_coltypes(PyObject *self, PyObject *unused)
 	PyObject   *list;
 	int			i;
 
+	if (!ob->tupdesc)
+	{
+		PLy_exception_set(PLy_exc_error, "command did not produce a result set");
+		return NULL;
+	}
+
 	list = PyList_New(ob->tupdesc->natts);
 	for (i = 0; i < ob->tupdesc->natts; i++)
 		PyList_SET_ITEM(list, i, PyInt_FromLong(ob->tupdesc->attrs[i]->atttypid));
@@ -159,6 +172,12 @@ PLy_result_coltypmods(PyObject *self, PyObject *unused)
 	PyObject   *list;
 	int			i;
 
+	if (!ob->tupdesc)
+	{
+		PLy_exception_set(PLy_exc_error, "command did not produce a result set");
+		return NULL;
+	}
+
 	list = PyList_New(ob->tupdesc->natts);
 	for (i = 0; i < ob->tupdesc->natts; i++)
 		PyList_SET_ITEM(list, i, PyInt_FromLong(ob->tupdesc->attrs[i]->atttypmod));