re PR libstdc++/45841 (r164529 cris-elf libstdc++ 27_io/basic_filebuf/seekoff/char/2-io.cc)

2010-10-05  David Krauss  <potswa@mac.com>

	PR libstdc++/45841
	* include/bits/fstream.h (basic_filebuf::underflow): Overflow
	success does not preclude returning failure.
	(basic_filebuf::pbackfail): Likewise.
	(basic_filebuf::xsputn): Fix indentation problem.
	(basic_filebuf::xsgetn): Likewise. Also, add similar overflow
	call to enable optimized case from write mode.
	* testsuite/27_io/basic_filebuf/underflow/char/45841.cc: New.
	* testsuite/27_io/basic_filebuf/underflow/wchar_t/45841.cc: Likewise.

From-SVN: r165009

libstdc++-v3/ChangeLog

+2010-10-05  David Krauss  <potswa@mac.com>
+
+	PR libstdc++/45841
+	* include/bits/fstream.h (basic_filebuf::underflow): Overflow
+	success does not preclude returning failure.
+	(basic_filebuf::pbackfail): Likewise.
+	(basic_filebuf::xsputn): Fix indentation problem.
+	(basic_filebuf::xsgetn): Likewise. Also, add similar overflow
+	call to enable optimized case from write mode.
+	* testsuite/27_io/basic_filebuf/underflow/char/45841.cc: New.
+	* testsuite/27_io/basic_filebuf/underflow/wchar_t/45841.cc: Likewise.
+
 2010-10-05  Jonathan Wakely  <jwakely.gcc@gmail.com>
 
 	* include/bits/locale_facets_nonio.h (time_get::get_time): Doc typo.

libstdc++-v3/include/bits/fstream.tcc

@@ -209,8 +209,7 @@ _GLIBCXX_BEGIN_NAMESPACE(std)
 	{
 	  if (_M_writing)
 	    {
-             __ret = overflow();
-             if (__ret == traits_type::eof())
+	      if (overflow() == traits_type::eof())
 		return __ret;
 	      _M_set_buffer(-1);
 	      _M_writing = false;
@@ -369,8 +368,7 @@ _GLIBCXX_BEGIN_NAMESPACE(std)
 	{
 	  if (_M_writing)
 	    {
-             __ret = overflow();
-             if (__ret == traits_type::eof())
+	      if (overflow() == traits_type::eof())
 		return __ret;
 	      _M_set_buffer(-1);
 	      _M_writing = false;
@@ -556,13 +554,20 @@ _GLIBCXX_BEGIN_NAMESPACE(std)
 	{
 	  if (__n > 0 && this->gptr() == this->eback())
 	    {
-	       *__s++ = *this->gptr();
+	      *__s++ = *this->gptr(); // emulate non-underflowing sbumpc
 	      this->gbump(1);
 	      __ret = 1;
 	      --__n;
 	    }
 	  _M_destroy_pback();
 	}
+      else if (_M_writing)
+	{
+ 	  if (overflow() == traits_type::eof())
+ 	    return __ret;
+ 	  _M_set_buffer(-1);
+ 	  _M_writing = false;
+ 	}
  
       // Optimization in the always_noconv() case, to be generalized in the
       // future: when __n > __buflen we read directly instead of using the
@@ -571,7 +576,7 @@ _GLIBCXX_BEGIN_NAMESPACE(std)
       const streamsize __buflen = _M_buf_size > 1 ? _M_buf_size - 1 : 1;
  
       if (__n > __buflen && __check_facet(_M_codecvt).always_noconv()
-	   && __testin && !_M_writing)
+ 	   && __testin)
  	 {
  	   // First, copy the chars already present in the buffer.
  	   const streamsize __avail = this->egptr() - this->gptr();
@@ -633,10 +638,10 @@ _GLIBCXX_BEGIN_NAMESPACE(std)
     basic_filebuf<_CharT, _Traits>::
     xsputn(const _CharT* __s, streamsize __n)
     {
+      streamsize __ret = 0;
       // Optimization in the always_noconv() case, to be generalized in the
       // future: when __n is sufficiently large we write directly instead of
       // using the buffer.
-       streamsize __ret = 0;
       const bool __testout = _M_mode & ios_base::out;
       if (__check_facet(_M_codecvt).always_noconv()
  	   && __testout && !_M_reading)
@@ -933,7 +938,8 @@ _GLIBCXX_BEGIN_NAMESPACE(std)
 		    {
 		      // External position corresponding to gptr().
 		      _M_ext_next = _M_ext_buf
-			+ _M_codecvt->length(_M_state_last, _M_ext_buf, _M_ext_next,
+			+ _M_codecvt->length(_M_state_last, _M_ext_buf,
+					     _M_ext_next,
 					     this->gptr() - this->eback());
 		      const streamsize __remainder = _M_ext_end - _M_ext_next;
 		      if (__remainder)

libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/char/45841.cc

+// Copyright (C) 2010 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 3, 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 COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+  using namespace std;
+
+  filebuf fb_in_out;
+
+  fb_in_out.open("tmp_underflow.tst", ios::in | ios::out | ios::trunc);
+
+  VERIFY( fb_in_out.sputc('x') == 'x' );
+  VERIFY( fb_in_out.sgetc() == filebuf::traits_type::eof() );
+  fb_in_out.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}

libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/45841.cc

+// Copyright (C) 2010 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 3, 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 COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+  using namespace std;
+
+  wfilebuf fb_in_out;
+
+  fb_in_out.open("tmp_underflow.tst", ios::in | ios::out | ios::trunc);
+
+  VERIFY( fb_in_out.sputc(L'x') == L'x' );
+  VERIFY( fb_in_out.sgetc() == wfilebuf::traits_type::eof() );
+  fb_in_out.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}