2004-10-06 Paolo Carlini <pcarlini@suse.de>

	* include/std/std_sstream.h (_M_sync): When the caller is
	setbuf, don't trust _M_string.capacity() to be the size of
	the buffer area, use _M_string.size() in this case.
	* testsuite/27_io/basic_stringbuf/setbuf/char/4.cc: New.
	* testsuite/27_io/basic_stringbuf/setbuf/wchar_t/4.cc: Likewise.

	* include/bits/sstream.tcc (overflow): Avoid calling string::assign
	unnecessarily when the current _M_string is empty.

2004-10-06  Paolo Carlini  <pcarlini@suse.de>

	* include/bits/stl_algo.h (__reverse(bidirectional_iterator_tag)):
	Avoid iterator postincrement.
	(__rotate): Likewise.

	* include/bits/stl_algo.h: Minor formatting tweaks.

2004-10-06  Christopher Jefferson <caj@cs.york.ac.uk>

	* include/bits/stl_algo.h (__reverse(random_access_iterator_tag)):
	Avoid iterator postincrement; fix swapping middle element with
	itself on odd-length inputs.


git-svn-id: https://gcc.gnu.org/svn/gcc/trunk@88593 138bc75d-0d04-0410-961f-82ee72b054a4

6 files changed, 182 insertions, 17 deletions

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index e26f127670e..9509eba9237 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,28 @@
+2004-10-06  Paolo Carlini  <pcarlini@suse.de>
+
+	* include/std/std_sstream.h (_M_sync): When the caller is
+	setbuf, don't trust _M_string.capacity() to be the size of
+	the buffer area, use _M_string.size() in this case.
+	* testsuite/27_io/basic_stringbuf/setbuf/char/4.cc: New.
+	* testsuite/27_io/basic_stringbuf/setbuf/wchar_t/4.cc: Likewise.
+
+	* include/bits/sstream.tcc (overflow): Avoid calling string::assign
+	unnecessarily when the current _M_string is empty.
+
+2004-10-06  Paolo Carlini  <pcarlini@suse.de>
+
+	* include/bits/stl_algo.h (__reverse(bidirectional_iterator_tag)):
+	Avoid iterator postincrement.
+	(__rotate): Likewise.
+
+	* include/bits/stl_algo.h: Minor formatting tweaks.
+
+2004-10-06  Christopher Jefferson <caj@cs.york.ac.uk>
+
+	* include/bits/stl_algo.h (__reverse(random_access_iterator_tag)):
+	Avoid iterator postincrement; fix swapping middle element with
+	itself on odd-length inputs.
+
 2004-10-05  Benjamin Kosnik  <bkoz@redhat.com>
 
 	PR libstdc++/17780
diff --git a/libstdc++-v3/include/bits/sstream.tcc b/libstdc++-v3/include/bits/sstream.tcc
index 985a0e46d07..86daa6d3ca3 100644
--- a/libstdc++-v3/include/bits/sstream.tcc
+++ b/libstdc++-v3/include/bits/sstream.tcc
@@ -109,7 +109,8 @@ namespace std
 	  const __size_type __len = std::min(__opt_len, __max_size);
 	  __string_type __tmp;
 	  __tmp.reserve(__len);
-	  __tmp.assign(_M_string.data(), this->epptr() - this->pbase());
+	  if (this->pbase())
+	    __tmp.assign(this->pbase(), this->epptr() - this->pbase());
 	  _M_string.swap(__tmp);
 	  _M_sync(const_cast<char_type*>(_M_string.data()),
 		  this->gptr() - this->eback(), this->pptr() - this->pbase());
diff --git a/libstdc++-v3/include/bits/stl_algo.h b/libstdc++-v3/include/bits/stl_algo.h
index a5118c57208..658a13435d2 100644
--- a/libstdc++-v3/include/bits/stl_algo.h
+++ b/libstdc++-v3/include/bits/stl_algo.h
@@ -1412,29 +1412,39 @@ namespace std
   template<typename _BidirectionalIterator>
     void
     __reverse(_BidirectionalIterator __first, _BidirectionalIterator __last,
-			  bidirectional_iterator_tag)
+	      bidirectional_iterator_tag)
     {
       while (true)
 	if (__first == __last || __first == --__last)
 	  return;
 	else
-	  std::iter_swap(__first++, __last);
+	  {
+	    std::iter_swap(__first, __last);
+	    ++__first;
+	  }
     }
 
   /**
    *  @if maint
    *  This is an uglified reverse(_BidirectionalIterator,
    *                              _BidirectionalIterator)
-   *  overloaded for bidirectional iterators.
+   *  overloaded for random access iterators.
    *  @endif
   */
   template<typename _RandomAccessIterator>
     void
     __reverse(_RandomAccessIterator __first, _RandomAccessIterator __last,
-			  random_access_iterator_tag)
+	      random_access_iterator_tag)
     {
+      if (__first == __last)
+	return;
+      --__last;
       while (__first < __last)
-	std::iter_swap(__first++, --__last);
+	{
+	  std::iter_swap(__first, __last);
+	  ++__first;
+	  --__last;
+	}
     }
 
   /**
@@ -1454,7 +1464,7 @@ namespace std
     {
       // concept requirements
       __glibcxx_function_requires(_Mutable_BidirectionalIteratorConcept<
-		    _BidirectionalIterator>)
+				  _BidirectionalIterator>)
       __glibcxx_requires_valid_range(__first, __last);
       std::__reverse(__first, __last, std::__iterator_category(__first));
     }
@@ -1525,15 +1535,17 @@ namespace std
     __rotate(_ForwardIterator __first,
 	     _ForwardIterator __middle,
 	     _ForwardIterator __last,
-	      forward_iterator_tag)
+	     forward_iterator_tag)
     {
-      if ((__first == __middle) || (__last  == __middle))
+      if (__first == __middle || __last  == __middle)
 	return;
 
       _ForwardIterator __first2 = __middle;
       do
 	{
-	  swap(*__first++, *__first2++);
+	  swap(*__first, *__first2);
+	  ++__first;
+	  ++__first2;
 	  if (__first == __middle)
 	    __middle = __first2;
 	}
@@ -1543,7 +1555,9 @@ namespace std
 
       while (__first2 != __last)
 	{
-	  swap(*__first++, *__first2++);
+	  swap(*__first, *__first2);
+	  ++__first;
+	  ++__first2;
 	  if (__first == __middle)
 	    __middle = __first2;
 	  else if (__first2 == __last)
@@ -1565,16 +1579,19 @@ namespace std
     {
       // concept requirements
       __glibcxx_function_requires(_Mutable_BidirectionalIteratorConcept<
-	    _BidirectionalIterator>)
+				  _BidirectionalIterator>)
 
-      if ((__first == __middle) || (__last  == __middle))
+      if (__first == __middle || __last  == __middle)
 	return;
 
       std::__reverse(__first,  __middle, bidirectional_iterator_tag());
       std::__reverse(__middle, __last,   bidirectional_iterator_tag());
 
       while (__first != __middle && __middle != __last)
-	swap(*__first++, *--__last);
+	{
+	  swap(*__first, *--__last);
+	  ++__first;
+	}
 
       if (__first == __middle)
 	std::__reverse(__middle, __last,   bidirectional_iterator_tag());
@@ -1596,9 +1613,9 @@ namespace std
     {
       // concept requirements
       __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
-	    _RandomAccessIterator>)
+				  _RandomAccessIterator>)
 
-      if ((__first == __middle) || (__last  == __middle))
+      if (__first == __middle || __last  == __middle)
 	return;
 
       typedef typename iterator_traits<_RandomAccessIterator>::difference_type
diff --git a/libstdc++-v3/include/std/std_sstream.h b/libstdc++-v3/include/std/std_sstream.h
index 3420999164c..fc4c42a3c78 100644
--- a/libstdc++-v3/include/std/std_sstream.h
+++ b/libstdc++-v3/include/std/std_sstream.h
@@ -259,7 +259,13 @@ namespace std
 	  this->setg(__base, __base + __i, __end);
 	if (__testout)
 	  {
-	    this->setp(__base, __base + _M_string.capacity());
+	    // If __base comes from setbuf we cannot trust capacity()
+	    // to match the size of the buffer area: in general, after
+	    // Step 1 above, _M_string.capacity() >= __n.
+	    if (__base == _M_string.data())
+	      this->setp(__base, __base + _M_string.capacity());
+	    else
+	      this->setp(__base, __end);
 	    this->pbump(__o);
 	    // egptr() always tracks the string end. When !__testin,
 	    // for the correct functioning of the streambuf inlines
diff --git a/libstdc++-v3/testsuite/27_io/basic_stringbuf/setbuf/char/4.cc b/libstdc++-v3/testsuite/27_io/basic_stringbuf/setbuf/char/4.cc
new file mode 100644
index 00000000000..0449af2e0f2
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_stringbuf/setbuf/char/4.cc
@@ -0,0 +1,58 @@
+// 2004-10-06  Paolo Carlini  <pcarlini@suse.de>
+
+// Copyright (C) 2004 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 <sstream>
+#include <testsuite_hooks.h>
+
+void test01()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  const unsigned max_size = 1 << 18;
+
+  char ref[max_size];
+  memset(ref, '\0', max_size);
+
+  char src[max_size * 2];
+  memset(src, '\1', max_size * 2);
+
+  for (unsigned i = 128; i <= max_size; i *= 2)
+    {
+      char* dest = new char[i * 2];
+      memset(dest, '\0', i * 2);
+
+      stringbuf sbuf;
+      sbuf.pubsetbuf(dest, i);
+
+      sbuf.sputn(src, i * 2);
+      VERIFY( !memcmp(dest + i, ref, i) );
+      
+      delete[] dest;
+    }
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_stringbuf/setbuf/wchar_t/4.cc b/libstdc++-v3/testsuite/27_io/basic_stringbuf/setbuf/wchar_t/4.cc
new file mode 100644
index 00000000000..e0eb8ded4cf
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_stringbuf/setbuf/wchar_t/4.cc
@@ -0,0 +1,58 @@
+// 2004-10-06  Paolo Carlini  <pcarlini@suse.de>
+
+// Copyright (C) 2004 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 <sstream>
+#include <testsuite_hooks.h>
+
+void test01()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  const unsigned max_size = 1 << 18;
+
+  wchar_t ref[max_size];
+  wmemset(ref, L'\0', max_size);
+
+  wchar_t src[max_size * 2];
+  wmemset(src, L'\1', max_size * 2);
+
+  for (unsigned i = 128; i <= max_size; i *= 2)
+    {
+      wchar_t* dest = new wchar_t[i * 2];
+      wmemset(dest, L'\0', i * 2);
+
+      wstringbuf sbuf;
+      sbuf.pubsetbuf(dest, i);
+
+      sbuf.sputn(src, i * 2);
+      VERIFY( !wmemcmp(dest + i, ref, i) );
+      
+      delete[] dest;
+    }
+}
+
+int main()
+{
+  test01();
+  return 0;
+}