Issue #6697: Check that _PyUnicode_AsString() result is not NULL in _sqlite

Strip also some trailing spaces

Modules/_sqlite/connection.c

@@ -495,7 +495,9 @@ void _pysqlite_set_result(sqlite3_context* context, PyObject* py_val)
     } else if (PyFloat_Check(py_val)) {
         sqlite3_result_double(context, PyFloat_AsDouble(py_val));
     } else if (PyUnicode_Check(py_val)) {
-        sqlite3_result_text(context, _PyUnicode_AsString(py_val), -1, SQLITE_TRANSIENT);
+        char *str = _PyUnicode_AsString(py_val);
+        if (str != NULL)
+            sqlite3_result_text(context, str, -1, SQLITE_TRANSIENT);
     } else if (PyObject_CheckBuffer(py_val)) {
         if (PyObject_AsCharBuffer(py_val, &buffer, &buflen) != 0) {
             PyErr_SetString(PyExc_ValueError, "could not convert BLOB to buffer");

Modules/_sqlite/cursor.c

@@ -533,7 +533,7 @@ PyObject* _pysqlite_query_execute(pysqlite_Cursor* self, int multiple, PyObject*
     }
 
     operation_cstr = _PyUnicode_AsStringAndSize(operation, &operation_len);
-    if (operation == NULL)
+    if (operation_cstr == NULL)
         goto error;
 
     /* reset description and rowcount */

Modules/_sqlite/row.c

@@ -83,6 +83,8 @@ PyObject* pysqlite_row_subscript(pysqlite_Row* self, PyObject* idx)
         return item;
     } else if (PyUnicode_Check(idx)) {
         key = _PyUnicode_AsString(idx);
+        if (key == NULL)
+            return NULL;
 
         nitems = PyTuple_Size(self->description);
 

Modules/_sqlite/statement.c

@@ -130,7 +130,10 @@ int pysqlite_statement_bind_parameter(pysqlite_Statement* self, int pos, PyObjec
             break;
         case TYPE_UNICODE:
             string = _PyUnicode_AsString(parameter);
+            if (string != NULL)
                 rc = sqlite3_bind_text(self->st, pos, string, -1, SQLITE_TRANSIENT);
+            else
+                rc = -1;
             break;
         case TYPE_BUFFER:
             if (PyObject_AsCharBuffer(parameter, &buffer, &buflen) == 0) {