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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.
//
//===----------------------------------------------------------------------===//
// <istream>
// template <class charT, class traits = char_traits<charT> >
// class basic_istream::sentry;
// explicit sentry(basic_istream<charT,traits>& is, bool noskipws = false);
#include <istream>
#include <cassert>
int sync_called = 0;
template <class CharT>
struct testbuf
: public std::basic_streambuf<CharT>
{
typedef std::basic_string<CharT> string_type;
typedef std::basic_streambuf<CharT> base;
private:
string_type str_;
public:
testbuf() {}
testbuf(const string_type& str)
: str_(str)
{
base::setg(const_cast<CharT*>(str_.data()),
const_cast<CharT*>(str_.data()),
const_cast<CharT*>(str_.data()) + str_.size());
}
CharT* eback() const {return base::eback();}
CharT* gptr() const {return base::gptr();}
CharT* egptr() const {return base::egptr();}
protected:
int virtual sync()
{
++sync_called;
return 1;
}
};
int main()
{
{
std::istream is((testbuf<char>*)0);
std::istream::sentry sen(is, true);
assert(!(bool)sen);
assert(!is.good());
assert(is.gcount() == 0);
assert(sync_called == 0);
}
{
std::wistream is((testbuf<wchar_t>*)0);
std::wistream::sentry sen(is, true);
assert(!(bool)sen);
assert(!is.good());
assert(is.gcount() == 0);
assert(sync_called == 0);
}
{
testbuf<char> sb(" 123");
std::istream is(&sb);
std::istream::sentry sen(is, true);
assert((bool)sen);
assert(is.good());
assert(is.gcount() == 0);
assert(sync_called == 0);
assert(sb.gptr() == sb.eback());
}
{
testbuf<wchar_t> sb(L" 123");
std::wistream is(&sb);
std::wistream::sentry sen(is, true);
assert((bool)sen);
assert(is.good());
assert(is.gcount() == 0);
assert(sync_called == 0);
assert(sb.gptr() == sb.eback());
}
{
testbuf<char> sb(" 123");
std::istream is(&sb);
std::istream::sentry sen(is);
assert((bool)sen);
assert(is.good());
assert(sync_called == 0);
assert(sb.gptr() == sb.eback() + 3);
}
{
testbuf<wchar_t> sb(L" 123");
std::wistream is(&sb);
std::wistream::sentry sen(is);
assert((bool)sen);
assert(is.good());
assert(sync_called == 0);
assert(sb.gptr() == sb.eback() + 3);
}
{
testbuf<char> sb(" ");
std::istream is(&sb);
std::istream::sentry sen(is);
assert(!(bool)sen);
assert(is.fail());
assert(is.eof());
assert(sync_called == 0);
assert(sb.gptr() == sb.eback() + 6);
}
{
testbuf<char> sb(" ");
std::istream is(&sb);
std::istream::sentry sen(is, true);
assert((bool)sen);
assert(is.good());
assert(sync_called == 0);
assert(sb.gptr() == sb.eback());
}
}
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