Fix for CONC-178:

9EOR9 · 9EOR9 · commit 5831a697211b · 2021-11-25T06:06:48.000+01:00
When a cursor was not properly cleared (all results weren't
fetched) the clear_result routine has to free result sets only
if field_count &gt; 0.
diff --git a/mariadb/mariadb_cursor.c b/mariadb/mariadb_cursor.c
@@ -405,12 +405,14 @@ PyObject *MrdbCursor_clear_result(MrdbCursor *self)
         self->stmt)
     {
         /* free current result */
-        mysql_stmt_free_result(self->stmt);
+        if (mysql_stmt_field_count(self->stmt))
+            mysql_stmt_free_result(self->stmt);
 
         /* check if there are more pending result sets */
         while (mysql_stmt_next_result(self->stmt) == 0)
         {
-            mysql_stmt_free_result(self->stmt);
+            if (mysql_stmt_field_count(self->stmt))
+                mysql_stmt_free_result(self->stmt);
         }
     } else if (self->parseinfo.is_text)
     {

Original file line number	Diff line number	Diff line change
`@@ -405,12 +405,14 @@ PyObject MrdbCursor_clear_result(MrdbCursor self)`
`405`	`405`	`self->stmt)`
`406`	`406`	`{`
`407`	`407`	`/* free current result */`
`408`		`- mysql_stmt_free_result(self->stmt);`
	`408`	`+ if (mysql_stmt_field_count(self->stmt))`
	`409`	`+ mysql_stmt_free_result(self->stmt);`
`409`	`410`
`410`	`411`	`/* check if there are more pending result sets */`
`411`	`412`	`while (mysql_stmt_next_result(self->stmt) == 0)`
`412`	`413`	`{`
`413`		`- mysql_stmt_free_result(self->stmt);`
	`414`	`+ if (mysql_stmt_field_count(self->stmt))`
	`415`	`+ mysql_stmt_free_result(self->stmt);`
`414`	`416`	`}`
`415`	`417`	`} else if (self->parseinfo.is_text)`
`416`	`418`	`{`