Make streams movable and swappable.

	PR libstdc++/54316
	PR libstdc++/53626
	* config/abi/pre/gnu.ver: Add new exports.
	* config/io/basic_file_stdio.h (__basic_file): Support moving and
	swapping.
	* include/bits/basic_ios.h (basic_ios::move, basic_ios::swap):
	Likewise.
	* include/bits/ios_base.h (ios_base::_M_move, ios_base::_M_swap):
	Likewise.
	* include/bits/fstream.tcc (basic_filebuf): Likewise.
	* include/bits/move.h (__exchange): Define for C++11 mode.
	* include/ext/stdio_filebuf.h (stdio_filebuf): Support moving and
	swapping.
	* include/ext/stdio_sync_filebuf.h (stdio_sync_filebuf): Likewise.
	* include/std/fstream (basic_filebuf, basic_ifstream, basic_ofstream,
	basic_fstream): Likewise.
	* include/std/ios: Remove whitespace.
	* include/std/istream (basic_istream, basic_iostream): Support moving
	and swapping.
	* include/std/ostream (basic_ostream): Likewise.
	* include/std/sstream (basic_stringbuf, basic_istringstream,
	basic_ostringstream, basic_stringstream): Likewise.
	* include/std/streambuf (basic_streambuf): Do not default copy
	constructor and assignment on first declaration.
	* include/std/utility (exchange): Forward to __exchange.
	* testsuite/27_io/basic_filebuf/cons/char/copy_neg.cc: New.
	* src/c++11/Makefile.am: Add stream-related files.
	* src/c++11/Makefile.in: Regenerate.
	* src/c++11/ext11-inst.cc (stdio_filebuf, stdio_sync_filebuf):
	New file for explicit instantiation definitions.
	* src/c++11/ios.cc: Move from src/c++98 to here.
	(ios_base::_M_move, ios_base::_M_swap): Define.
	* src/c++11/ios-inst.cc: Move from src/c++98 to here.
	* src/c++11/iostream-inst.cc: Likewise.
	* src/c++11/istream-inst.cc: Likewise.
	* src/c++11/ostream-inst.cc: Likewise.
	* src/c++11/sstream-inst.cc: Likewise.
	* src/c++11/streambuf-inst.cc: Likewise.
	* src/c++98/Makefile.am: Remove stream-related files.
	* src/c++98/Makefile.in: Regenerate.
	* src/c++98/ext-inst.cc (stdio_filebuf): Remove explicit
	instantiations.
	* src/c++98/misc-inst.cc (stdio_sync_filebuf): Likewise.
	* src/c++98/ios-inst.cc: Move to src/c++11/.
	* src/c++98/ios.cc: Move to src/c++11/.
	* src/c++98/iostream-inst.cc: Likewise.
	* src/c++98/istream-inst.cc: Likewise.
	* src/c++98/ostream-inst.cc: Likewise.
	* src/c++98/sstream-inst.cc: Likewise.
	* src/c++98/streambuf-inst.cc: Likewise.
	* testsuite/27_io/basic_filebuf/cons/char/copy_neg.cc: New.
	* testsuite/27_io/basic_fstream/cons/move.cc: New.
	* testsuite/27_io/basic_fstream/assign/1.cc: New.
	* testsuite/27_io/basic_ifstream/cons/move.cc: New.
	* testsuite/27_io/basic_ifstream/assign/1.cc: New.
	* testsuite/27_io/basic_istringstream/assign/1.cc: New.
	* testsuite/27_io/basic_istringstream/cons/move.cc: New.
	* testsuite/27_io/basic_ofstream/cons/move.cc: New.
	* testsuite/27_io/basic_ofstream/assign/1.cc: New.
	* testsuite/27_io/basic_ostringstream/assign/1.cc: New.
	* testsuite/27_io/basic_ostringstream/cons/move.cc: New.
	* testsuite/27_io/basic_stringstream/assign/1.cc: New.
	* testsuite/27_io/basic_stringstream/cons/move.cc: New.

From-SVN: r215463

1 files changed, 31 insertions, 1 deletions

diff --git a/libstdc++-v3/include/ext/stdio_sync_filebuf.h b/libstdc++-v3/include/ext/stdio_sync_filebuf.h
index 73283a7..c881172 100644
--- a/libstdc++-v3/include/ext/stdio_sync_filebuf.h
+++ b/libstdc++-v3/include/ext/stdio_sync_filebuf.h
@@ -35,6 +35,7 @@
 #include <unistd.h>
 #include <cstdio>
 #include <bits/c++io.h>  // For __c_file
+#include <bits/move.h>   // For __exchange
 
 #ifdef _GLIBCXX_USE_WCHAR_T
 #include <cwchar>
@@ -64,8 +65,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       typedef typename traits_type::off_type		off_type;
 
     private:
+      typedef std::basic_streambuf<_CharT, _Traits> __streambuf_type;
+
       // Underlying stdio FILE
-      std::__c_file* const _M_file;
+      std::__c_file* _M_file;
 
       // Last character gotten. This is used when pbackfail is
       // called from basic_streambuf::sungetc()
@@ -77,6 +80,33 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       : _M_file(__f), _M_unget_buf(traits_type::eof())
       { }
 
+#if __cplusplus >= 201103L
+      stdio_sync_filebuf(stdio_sync_filebuf&& __fb) noexcept
+      : __streambuf_type(std::move(__fb)),
+      _M_file(__fb._M_file), _M_unget_buf(__fb._M_unget_buf)
+      {
+	__fb._M_file = nullptr;
+	__fb._M_unget_buf = traits_type::eof();
+      }
+
+      stdio_sync_filebuf&
+      operator=(stdio_sync_filebuf&& __fb) noexcept
+      {
+	__streambuf_type::operator=(__fb);
+	_M_file = std::__exchange(__fb._M_file, nullptr);
+	_M_unget_buf = std::__exchange(__fb._M_unget_buf, traits_type::eof());
+	return *this;
+      }
+
+      void
+      swap(stdio_sync_filebuf& __fb)
+      {
+	__streambuf_type::swap(__fb);
+	std::swap(_M_file, __fb._M_file);
+	std::swap(_M_unget_buf, __fb._M_unget_buf);
+      }
+#endif
+
       /**
        *  @return  The underlying FILE*.
        *