60 lines · cpp
1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9// <streambuf>10 11// template <class charT, class traits = char_traits<charT> >12// class basic_streambuf;13 14// int_type sgetc();15 16#include <streambuf>17#include <cassert>18 19#include "test_macros.h"20 21int underflow_called = 0;22 23struct test24 : public std::basic_streambuf<char>25{26 typedef std::basic_streambuf<char> base;27 28 test() {}29 30 void setg(char* gbeg, char* gnext, char* gend)31 {32 base::setg(gbeg, gnext, gend);33 }34 35protected:36 int_type underflow()37 {38 ++underflow_called;39 return 'a';40 }41};42 43int main(int, char**)44{45 {46 test t;47 assert(underflow_called == 0);48 assert(t.sgetc() == 'a');49 assert(underflow_called == 1);50 char in[] = "ABC";51 t.setg(in, in, in+sizeof(in));52 assert(t.sgetc() == 'A');53 assert(underflow_called == 1);54 assert(t.sgetc() == 'A');55 assert(underflow_called == 1);56 }57 58 return 0;59}60