From 2cfe4e6898684773bb75f5781b867678084a2377 Mon Sep 17 00:00:00 2001 From: Paolo Carlini Date: Thu, 26 Jun 2003 11:55:24 +0200 Subject: [PATCH] Nathan C. 2003-06-26 Paolo Carlini Nathan C. Myers * include/bits/fstream.tcc (_M_underflow): When the actual end of file is reached, set 'uncommitted' mode to allow a next write without an intervening seek (see C++98 27.8.1.1,2 and C89 7.9.5.3). * testsuite/27_io/basic_filebuf/underflow/char/2.cc: New. Co-Authored-By: Nathan C. Myers From-SVN: r68522 --- libstdc++-v3/ChangeLog | 9 ++++ libstdc++-v3/include/bits/fstream.tcc | 12 ++++- .../27_io/basic_filebuf/underflow/char/2.cc | 48 +++++++++++++++++++ 3 files changed, 67 insertions(+), 2 deletions(-) create mode 100644 libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/char/2.cc diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog index 2a494a148b9..4d244376d97 100644 --- a/libstdc++-v3/ChangeLog +++ b/libstdc++-v3/ChangeLog @@ -1,3 +1,12 @@ +2003-06-26 Paolo Carlini + Nathan C. Myers + + * include/bits/fstream.tcc (_M_underflow): When the actual + end of file is reached, set 'uncommitted' mode to allow a + next write without an intervening seek (see C++98 27.8.1.1,2 + and C89 7.9.5.3). + * testsuite/27_io/basic_filebuf/underflow/char/2.cc: New. + 2003-06-25 Nathan C. Myers * include/bits/streambuf.tcc (sbumpc, sputbackc, sungetc, diff --git a/libstdc++-v3/include/bits/fstream.tcc b/libstdc++-v3/include/bits/fstream.tcc index 22a24dcee69..1568b6015fe 100644 --- a/libstdc++-v3/include/bits/fstream.tcc +++ b/libstdc++-v3/include/bits/fstream.tcc @@ -215,7 +215,7 @@ namespace std { char* __buf = static_cast(__builtin_alloca(__buflen)); __elen = _M_file.xsgetn(__buf, __buflen); - + const char* __eend; char_type* __iend; codecvt_base::result __r; @@ -246,7 +246,15 @@ namespace std __ret = traits_type::to_int_type(*this->gptr()); if (__bump) this->gbump(1); - } + } + else if (__elen == 0) + { + // If the actual end of file is reached, set 'uncommitted' + // mode, thus allowing an immediate write without an + // intervening seek. + _M_set_buffer(-1); + _M_reading = false; + } } _M_last_overflowed = false; return __ret; diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/char/2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/char/2.cc new file mode 100644 index 00000000000..8032a42f6c8 --- /dev/null +++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/char/2.cc @@ -0,0 +1,48 @@ +// 2003-06-25 Paolo Carlini + +// Copyright (C) 2003 Free Software Foundation, Inc. +// +// This file is part of the GNU ISO C++ Library. This library is free +// software; you can redistribute it and/or modify it under the +// terms of the GNU General Public License as published by the +// Free Software Foundation; either version 2, or (at your option) +// any later version. + +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. + +// You should have received a copy of the GNU General Public License along +// with this library; see the file COPYING. If not, write to the Free +// Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, +// USA. + +// 27.8.1.4 Overridden virtual functions + +#include +#include + +void test01() +{ + bool test = true; + using namespace std; + + filebuf fb_out, fb_in_out; + + fb_out.open("tmp_underflow.tst", ios::out); + fb_out.sputc('S'); + fb_out.sputc('T'); + fb_out.close(); + + fb_in_out.open("tmp_underflow.tst", ios::in | ios::out); + while (fb_in_out.sbumpc() != filebuf::traits_type::eof()); + + VERIFY( fb_in_out.sputc('x') == 'x' ); + fb_in_out.close(); +} + +int main() +{ + test01(); +} -- 2.30.2