Function PLy_procedure_call

src/pl/plpython/plpy_exec.c:1067–1106

execute Python code, propagate Python errors to the backend */

/* execute Python code, propagate Python errors to the backend */
static PyObject *
PLy_procedure_call(PLyProcedure *proc, const char *kargs, PyObject *vargs)
{
	PyObject   *rv = NULL;
	int volatile save_subxact_level = list_length(explicit_subtransactions);

	PyDict_SetItemString(proc->globals, kargs, vargs);

	PG_TRY();
	{
		PLy_enter_python_intepreter = true;
#if PY_VERSION_HEX >= 0x03020000
		rv = PyEval_EvalCode(proc->code,
							 proc->globals, proc->globals);
#else
		rv = PyEval_EvalCode((PyCodeObject *) proc->code,
							 proc->globals, proc->globals);
#endif
		PLy_enter_python_intepreter = false;

		/*
		 * Since plpy will only let you close subtransactions that you
		 * started, you cannot *unnest* subtransactions, only *nest* them
		 * without closing.
		 */
		Assert(list_length(explicit_subtransactions) >= save_subxact_level);
	}
	PG_FINALLY();
	{
		PLy_enter_python_intepreter = false;
		PLy_abort_open_subtransactions(save_subxact_level);
	}
	PG_END_TRY();

	/* If the Python code returned an error, propagate it */
	if (rv == NULL)
		PLy_elog(ERROR, NULL);

	return rv;
}

/*
 * Abort lingering subtransactions that have been explicitly started