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//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// <fstream>
// int_type underflow();
// This test is not entirely portable
#include <fstream>
#include <cassert>
#include "platform_support.h" // locale name macros
template <class CharT>
struct test_buf
: public std::basic_filebuf<CharT>
{
typedef std::basic_filebuf<CharT> base;
typedef typename base::char_type char_type;
typedef typename base::int_type int_type;
char_type* eback() const {return base::eback();}
char_type* gptr() const {return base::gptr();}
char_type* egptr() const {return base::egptr();}
void gbump(int n) {base::gbump(n);}
virtual int_type underflow() {return base::underflow();}
};
int main()
{
{
test_buf<char> f;
assert(f.open("underflow.dat", std::ios_base::in) != 0);
assert(f.is_open());
assert(f.eback() == 0);
assert(f.gptr() == 0);
assert(f.egptr() == 0);
assert(f.underflow() == '1');
assert(f.eback() != 0);
assert(f.eback() == f.gptr());
assert(*f.gptr() == '1');
assert(f.egptr() - f.eback() == 9);
}
{
test_buf<char> f;
assert(f.open("underflow.dat", std::ios_base::in) != 0);
assert(f.pubsetbuf(0, 0));
assert(f.is_open());
assert(f.eback() == 0);
assert(f.gptr() == 0);
assert(f.egptr() == 0);
assert(f.underflow() == '1');
assert(f.eback() != 0);
assert(f.eback() == f.gptr());
assert(*f.gptr() == '1');
assert(f.egptr() - f.eback() == 8);
f.gbump(8);
assert(f.sgetc() == '9');
assert(f.eback()[0] == '5');
assert(f.eback()[1] == '6');
assert(f.eback()[2] == '7');
assert(f.eback()[3] == '8');
assert(f.gptr() - f.eback() == 4);
assert(*f.gptr() == '9');
assert(f.egptr() - f.gptr() == 1);
}
{
test_buf<wchar_t> f;
assert(f.open("underflow.dat", std::ios_base::in) != 0);
assert(f.is_open());
assert(f.eback() == 0);
assert(f.gptr() == 0);
assert(f.egptr() == 0);
assert(f.underflow() == L'1');
assert(f.eback() != 0);
assert(f.eback() == f.gptr());
assert(*f.gptr() == L'1');
assert(f.egptr() - f.eback() == 9);
}
{
test_buf<wchar_t> f;
assert(f.pubsetbuf(0, 0));
assert(f.open("underflow.dat", std::ios_base::in) != 0);
assert(f.is_open());
assert(f.eback() == 0);
assert(f.gptr() == 0);
assert(f.egptr() == 0);
assert(f.underflow() == L'1');
assert(f.eback() != 0);
assert(f.eback() == f.gptr());
assert(*f.gptr() == L'1');
assert(f.egptr() - f.eback() == 8);
f.gbump(8);
assert(f.sgetc() == L'9');
assert(f.eback()[0] == L'5');
assert(f.eback()[1] == L'6');
assert(f.eback()[2] == L'7');
assert(f.eback()[3] == L'8');
assert(f.gptr() - f.eback() == 4);
assert(*f.gptr() == L'9');
assert(f.egptr() - f.gptr() == 1);
}
{
test_buf<wchar_t> f;
f.pubimbue(std::locale(LOCALE_en_US_UTF_8));
assert(f.open("underflow_utf8.dat", std::ios_base::in) != 0);
assert(f.is_open());
assert(f.sbumpc() == 0x4E51);
assert(f.sbumpc() == 0x4E52);
assert(f.sbumpc() == 0x4E53);
assert(f.sbumpc() == -1);
}
}
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