1//===----------------------------------------------------------------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is dual licensed under the MIT and the University of Illinois Open 6// Source Licenses. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9 10// <strstream> 11 12// class strstreambuf 13 14// int_type underflow(); 15 16#include <strstream> 17#include <cassert> 18 19struct test 20 : public std::strstreambuf 21{ 22 typedef std::strstreambuf base; 23 test(char* gnext_arg, std::streamsize n, char* pbeg_arg = 0) 24 : base(gnext_arg, n, pbeg_arg) {} 25 test(const char* gnext_arg, std::streamsize n) 26 : base(gnext_arg, n) {} 27 28 base::int_type underflow() {return base::underflow();} 29}; 30 31int main() 32{ 33 { 34 char buf[10] = "123"; 35 test sb(buf, 0, buf + 3); 36 assert(sb.underflow() == '1'); 37 assert(sb.underflow() == '1'); 38 assert(sb.snextc() == '2'); 39 assert(sb.underflow() == '2'); 40 assert(sb.underflow() == '2'); 41 assert(sb.snextc() == '3'); 42 assert(sb.underflow() == '3'); 43 assert(sb.underflow() == '3'); 44 assert(sb.snextc() == EOF); 45 assert(sb.underflow() == EOF); 46 assert(sb.underflow() == EOF); 47 sb.sputc('4'); 48 assert(sb.underflow() == '4'); 49 assert(sb.underflow() == '4'); 50 } 51} 52