2000-07-20 Benjamin Kosnik <bkoz@cygnus.com>

	* bits/std_streambuf.h: Add bits for pback buffers here, so that
	in_avail, etc can use them.
	* bits/std_fstream.h: Ditto.
	* bits/fstream.tcc: Ditto.
	* testsuite/27_io/filebuf.cc: Tweaks.
	* testsuite/27_io/filebuf-3.tst: Correct for pbackfail bits.

2000-07-19  Benjamin Kosnik  <bkoz@cygnus.com>

	* src/localename.cc: Same.
	* src/locale.cc: Same.
	* bits/localefwd.h: _M_init_facet to _M_facet_init.

	* bits/locale_facets.h: _M_init_boolnames to _M_boolnames_init.

	* bits/std_sstream.h: Change _M_init_stringbuf to _M_stringbuf_init.

	* bits/fstream.tcc: Change _M_init_filebuf to _M_filebuf_init.
	* bits/std_fstream.h: Same.

	* bits/basic_string.h: Tweaks.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@35157 138bc75d-0d04-0410-961f-82ee72b054a4

12 files changed, 302 insertions, 194 deletions

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index 6f6b8126209..d2e2e536c63 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,27 @@
+2000-07-20  Benjamin Kosnik  <bkoz@cygnus.com>
+
+	* bits/std_streambuf.h: Add bits for pback buffers here, so that
+	in_avail, etc can use them.
+	* bits/std_fstream.h: Ditto.
+	* bits/fstream.tcc: Ditto.
+	* testsuite/27_io/filebuf.cc: Tweaks.
+	* testsuite/27_io/filebuf-3.tst: Correct for pbackfail bits.
+
+2000-07-19  Benjamin Kosnik  <bkoz@cygnus.com>
+
+	* src/localename.cc: Same.
+	* src/locale.cc: Same.
+	* bits/localefwd.h: _M_init_facet to _M_facet_init.
+
+	* bits/locale_facets.h: _M_init_boolnames to _M_boolnames_init.
+
+	* bits/std_sstream.h: Change _M_init_stringbuf to _M_stringbuf_init.
+
+	* bits/fstream.tcc: Change _M_init_filebuf to _M_filebuf_init.
+	* bits/std_fstream.h: Same.
+
+	* bits/basic_string.h: Tweaks.
+	
 2000-07-19  Phil Edwards  <pme@sourceware.cygnus.com>
 
 	* docs/18_support/howto.html:  Update.
diff --git a/libstdc++-v3/bits/basic_string.h b/libstdc++-v3/bits/basic_string.h
index 99401e6053f..0d21c2d9a2f 100644
--- a/libstdc++-v3/bits/basic_string.h
+++ b/libstdc++-v3/bits/basic_string.h
@@ -221,11 +221,11 @@ namespace std {
       // Data Members (public):
       // NB: This is an unsigned type, and thus represents the maximum
       // size that the allocator can hold.
-      static const size_type npos = static_cast<size_type>(-1);
+      static const size_type 	npos = static_cast<size_type>(-1);
 
     private:
       // Data Members (private):
-      mutable _Alloc_hider _M_dataplus;
+      mutable _Alloc_hider 	_M_dataplus;
 
       // The following storage is init'd to 0 by the linker, resulting
       // (carefully) in an empty string with one reference.
diff --git a/libstdc++-v3/bits/fstream.tcc b/libstdc++-v3/bits/fstream.tcc
index 556c110bbe0..7f334524458 100644
--- a/libstdc++-v3/bits/fstream.tcc
+++ b/libstdc++-v3/bits/fstream.tcc
@@ -39,7 +39,7 @@ namespace std
   template<typename _CharT, typename _Traits>
     void
     basic_filebuf<_CharT, _Traits>::
-    _M_init_filebuf(void)
+    _M_filebuf_init()
     {
       _M_buf_unified = true; // Tie input to output for basic_filebuf.
       _M_buf_size = _M_buf_size_opt;
@@ -50,6 +50,30 @@ namespace std
 	delete _M_file;
 	throw;
       }
+     }
+
+  template<typename _CharT, typename _Traits>
+    void
+    basic_filebuf<_CharT, _Traits>::
+    _M_allocate_buffers()
+    {
+      // Allocate internal buffer.
+      try {
+	_M_buf = new char_type[_M_buf_size];
+      }
+      catch(...) {
+	delete [] _M_buf;
+	throw;
+      }
+      
+      // Allocate pback buffer.
+      try {
+	_M_pback = new char_type[_M_pback_size];
+      }
+      catch(...) {
+	delete [] _M_pback;
+	throw;
+      }
     }
 
   template<typename _CharT, typename _Traits>
@@ -66,24 +90,18 @@ namespace std
     _M_last_overflowed(false)
     {
       _M_fcvt = &use_facet<__codecvt_type>(this->getloc());
-      _M_init_filebuf();
+      _M_filebuf_init();
       _M_file->sys_open(__fd, __mode);
       if (this->is_open() && _M_buf_size)
 	{
+	  _M_allocate_buffers();
 	  _M_mode = __mode;
+
 	  // XXX So that istream::getc() will only need to get 1 char,
 	  // as opposed to BUF_SIZE.
 	  if (__fd == 0)
 	    _M_buf_size = 1;
 
-	  try {
-	    _M_buf = new char_type[_M_buf_size];
-	  }
-	  catch(...) {
-	    delete [] _M_buf;
-	    throw;
-	  }
-
 	  this->_M_set_indeterminate();
 	}
    }
@@ -96,19 +114,12 @@ namespace std
       __filebuf_type *__retval = NULL;
       if (!this->is_open())
 	{
-	  _M_init_filebuf();
+	  _M_filebuf_init();
 	  _M_file->open(__s, __mode);
 	  if (this->is_open() && _M_buf_size)
 	    {
+	      _M_allocate_buffers();
 	      _M_mode = __mode;
-
-	      try {
-		_M_buf = new char_type[_M_buf_size];
-	      }
-	      catch(...) {
-		delete [] _M_buf;
-		throw;
-	      }
 	      
 	      // For time being, set both (in/out) sets  of pointers.
 	      _M_set_indeterminate();
@@ -132,7 +143,10 @@ namespace std
 	  bool __testput = _M_out_cur && _M_out_beg < _M_out_end;
 	  if (__testput)
 	    _M_really_overflow(traits_type::eof());
-	  
+
+	  // NB: Do this here so that re-opened filebufs will be cool...
+	  _M_pback_destroy();
+
 #if 0
 	  // XXX not done
 	  if (_M_last_overflowed)
@@ -142,18 +156,23 @@ namespace std
 	    }
 #endif
 
-	  if (_M_file)
-	    {
-	      delete _M_file;
-	      _M_file = NULL;
-	      _M_mode = ios_base::openmode(0);
-	      if (_M_buf_size)
-		delete [] _M_buf;
-	      _M_buf = NULL;
-	      this->setg(NULL, NULL, NULL);
-	      this->setp(NULL, NULL);
-	      __retval = this;
-	    }
+	  _M_mode = ios_base::openmode(0);
+	  if (_M_buf_size)
+	    delete [] _M_buf;
+	  _M_buf = NULL;
+	  delete [] _M_pback;
+	  _M_pback = NULL;
+	  this->setg(NULL, NULL, NULL);
+	  this->setp(NULL, NULL);
+	  __retval = this;
+	}
+
+      // Can actually allocate this file as part of an open and never
+      // have it be opened.....
+      if (_M_file)
+	{
+	  delete _M_file;
+	  _M_file = NULL;
 	}
       _M_last_overflowed = false;	
       return __retval;
@@ -173,7 +192,7 @@ namespace std
 	  if (_M_in_cur >= _M_in_end)
 	    __testeof = this->underflow() == traits_type::eof();
 	  if (!__testeof)
-	    __retval = (_M_in_end - _M_in_cur) / sizeof(char_type);
+	    __retval = _M_in_end - _M_in_cur;
 	}
       _M_last_overflowed = false;	
       return __retval;
@@ -185,13 +204,24 @@ namespace std
     underflow()
     {
       int_type __retval = traits_type::eof();
-      bool __testget = _M_in_cur && _M_in_beg < _M_in_cur;
-      bool __testinit = _M_is_indeterminate();
-      bool __testout = _M_mode & ios_base::out;
       bool __testin = _M_mode & ios_base::in;
       
       if (__testin)
 	{
+	  // Check for pback madness, and if so swich back to the
+	  // normal buffers and jet outta here before expensive
+	  // fileops happen...
+	  if (_M_pback_init)
+	    {
+	      _M_pback_destroy();
+	      if (_M_in_cur < _M_in_end)
+		return traits_type::to_int_type(*_M_in_cur);
+	    }
+
+	  bool __testget = _M_in_cur && _M_in_beg < _M_in_cur;
+	  bool __testinit = _M_is_indeterminate();
+	  bool __testout = _M_mode & ios_base::out;
+
 	  // Sync internal and external buffers.
 	  // NB: __testget -> __testput as _M_buf_unified here.
 	  if (__testget)
@@ -260,56 +290,63 @@ namespace std
     pbackfail(int_type __i)
     {
       int_type __retval = traits_type::eof();
-      char_type __c = traits_type::to_char_type(__i);
-      bool __testeof = traits_type::eq_int_type(__i, traits_type::eof());
-      bool __testout = _M_mode & ios_base::out;
       bool __testin = _M_mode & ios_base::in;
 
       if (__testin)
 	{
-	  if (!_M_is_indeterminate())	  
+	  bool __testpb = _M_in_beg < _M_in_cur;
+	  char_type __c = traits_type::to_char_type(__i);
+	  bool __testeof = traits_type::eq_int_type(__i, __retval);
+
+	  if (__testpb)
 	    {
-	      bool __testpb = _M_in_beg < _M_in_cur;
+	      bool __testout = _M_mode & ios_base::out;
 	      bool __testeq = traits_type::eq(__c, this->gptr()[-1]);
 
 	      // Try to put back __c into input sequence in one of three ways.
 	      // Order these tests done in is unspecified by the standard.
-	      if (!__testeof && __testpb && __testeq)
+	      if (!__testeof && __testeq)
 		{
 		  --_M_in_cur;
 		  if (__testout)
 		    --_M_out_cur;
 		  __retval = __i;
 		}
-	      else if (!__testeof && __testpb && __testout)
+	      else if (__testeof)
 		{
 		  --_M_in_cur;
 		  if (__testout)
 		    --_M_out_cur;
-		  *_M_in_cur = __c;
-		  __retval = __i;
+		  __retval = traits_type::not_eof(__i);
 		}
-	      else if (__testeof && __testpb)
+	      else if (!__testeof)
 		{
 		  --_M_in_cur;
 		  if (__testout)
 		    --_M_out_cur;
-		  __retval = traits_type::not_eof(__i);
+		  _M_pback_create();
+		  *_M_in_cur = __c; 
+		  __retval = __i;
 		}
 	    }
 	  else
-	    {
-	      // Need to make a putback position available.
+	    {	 
+ 	      // At the beginning of the buffer, need to make a
+	      // putback position available.
 	      this->seekoff(-1, ios_base::cur);
 	      this->underflow();
-	      if (!__testeof)
-		{
-		  *_M_in_cur = __c;
-		  __retval = __c;
-		}
-	      else
-		__retval = traits_type::not_eof(__i);
-	    }
+ 	      if (!__testeof)
+ 		{
+		  if (!traits_type::eq(__c, *_M_in_cur))
+		    {
+		      _M_pback_create();
+		      *_M_in_cur = __c;
+		    }
+ 		  __retval = __i;
+ 		}
+ 	      else
+ 		__retval = traits_type::not_eof(__i);
+ 	    }
 	}
       _M_last_overflowed = false;	
       return __retval;
@@ -355,7 +392,7 @@ namespace std
 	  // stack. Convert internal buffer plus __c (ie,
 	  // "pending sequence") to temporary conversion buffer.
 	  int __plen = _M_out_end - _M_out_beg;
-	  char_type __pbuf[__plen + sizeof(char_type)];	      
+	  char_type __pbuf[__plen + 1];	      
 	  traits_type::copy(__pbuf, this->pbase(), __plen);
 	  if (!__testeof)
 	    {
@@ -411,6 +448,9 @@ namespace std
       
       if (__testopen && !__testfail && (__testin || __testout))
 	{
+	  // Ditch any pback buffers to avoid confusion.
+	  _M_pback_destroy();
+
 	  if (__way != ios_base::cur || __off != 0)
 	    { 
 	      off_type __computed_off = __width * __off;
@@ -464,68 +504,7 @@ namespace std
     void 
     basic_filebuf<_CharT, _Traits>::
     _M_output_unshift()
-    {
-#if 0
-      // XXX Not complete, or correct.
-      int __width = _M_fcvt->encoding();
-      
-      if (__width < 0)
-	{
-	  // Part one: call codecvt::unshift
-	  int __unsft_len = 0;
-	  char_type __unsft_buf[_M_buf_size];
-	    char_type* __unsft_cur; // XXX Set to external buf.
-	    _M_state_beg = _M_state_cur;
-	    __res_type __r = _M_fcvt->unshift(_M_state_cur, 
-					      __unsft_buf,
-					      __unsft_buf + _M_buf_size,
-					      __unsft_cur);
-	    
-	    // Note, for char_type == char, wchar_t unshift
-	    // should store no charachers.
-	    if (__r == codecvt_base::ok || __r == codecvt_base::noconv)
-	      __unsft_len = __unsft_cur - __unsft_buf;
-	    
-	    // "Output the resulting sequence."
-	    if (__unsft_len)
-	      {
-		int __plen = _M_out_cur - _M_out_beg;
-		int __rlen = __plen  + __unsft_len;
-		char_type __rbuf[__rlen];
-		char_type* __rend;
-		traits_type::copy(__rbuf, this->pbase(), __plen);
-		traits_type::copy(__rbuf + __plen, __unsft_buf, 
-				  __unsft_len);
-
-		char __conv_buf[__rlen];
-		char* __conv_end;
-		
-		_M_state_beg = _M_state_cur; // XXX Needed?
-		__r = _M_fcvt->out(_M_state_cur, 
-				  __rbuf, __rbuf + __rlen,
-				  const_cast<const char_type*&>(__rend),
-				  __conv_buf, 
-				  __conv_buf + __rlen,
-				  __conv_end);
-		
-		if (__r != codecvt_base::error)
-		  {
-		    streamsize __r = _M_file->xsputn(__conv_buf, __rlen);
-		    if (__r == __rlen)
-		      {
-			_M_out_cur = _M_out_beg;
-			if (_M_mode & ios_base::in)
-			  _M_in_cur = _M_out_cur;
-		      }
-		    else
-		      {
-			// XXX Throw "wig out and die exception?"
-		      }
-		  }
-	      }
-	  }
-#endif
-    }
+    { }
 
   template<typename _CharT, typename _Traits>
     void
diff --git a/libstdc++-v3/bits/locale_facets.h b/libstdc++-v3/bits/locale_facets.h
index 1c73ab9e2bb..14be3f25c56 100644
--- a/libstdc++-v3/bits/locale_facets.h
+++ b/libstdc++-v3/bits/locale_facets.h
@@ -1268,7 +1268,7 @@ namespace std
     protected:
       // For use only during construction
       void 
-      _M_init_boolnames(const string_type& __t, const string_type& __f)
+      _M_boolnames_init(const string_type& __t, const string_type& __f)
       {
 	_M_truename = __t;
 	_M_falsename = __f;
@@ -1297,7 +1297,7 @@ namespace std
     numpunct<char>::numpunct(size_t __refs): _Numpunct<char>(__refs)
     {
       _M_init('.', ',', "");
-      _M_init_boolnames("true", "false");
+      _M_boolnames_init("true", "false");
     }
 
 #ifdef _GLIBCPP_USE_WCHAR_T
@@ -1305,7 +1305,7 @@ namespace std
     numpunct<wchar_t>::numpunct(size_t __refs): _Numpunct<wchar_t>(__refs)
     {
       _M_init(L'.', L',', "");
-      _M_init_boolnames(L"true", L"false");
+      _M_boolnames_init(L"true", L"false");
     }
 #endif
 
diff --git a/libstdc++-v3/bits/localefwd.h b/libstdc++-v3/bits/localefwd.h
index 7f12457c8bc..ceb376c02b6 100644
--- a/libstdc++-v3/bits/localefwd.h
+++ b/libstdc++-v3/bits/localefwd.h
@@ -370,7 +370,7 @@ namespace std
 
     template<typename _Facet>
       inline void 
-      _M_init_facet(_Facet* __facet)
+      _M_facet_init(_Facet* __facet)
       { _M_install_facet(&_Facet::id, __facet);  }
 
     void 
diff --git a/libstdc++-v3/bits/std_fstream.h b/libstdc++-v3/bits/std_fstream.h
index 045bb60b092..4ffbb245447 100644
--- a/libstdc++-v3/bits/std_fstream.h
+++ b/libstdc++-v3/bits/std_fstream.h
@@ -52,7 +52,7 @@ namespace std {
       typedef typename traits_type::int_type 		int_type;
       typedef typename traits_type::pos_type 		pos_type;
       typedef typename traits_type::off_type 		off_type;
-
+      
       // Non-standard Types:
       typedef basic_streambuf<char_type, traits_type>  	__streambuf_type;
       typedef basic_filebuf<char_type, traits_type>     __filebuf_type;
@@ -65,13 +65,22 @@ namespace std {
 
     private:
       // Data Members:
+      // External buffer.
       __file_type* 		_M_file;
-      __state_type		_M_state_cur;// Current state type for codecvt.
+
+      // Current and beginning state type for codecvt.
+      __state_type		_M_state_cur;
       __state_type 		_M_state_beg; 	
-      const __codecvt_type*	_M_fcvt;       // Cached value from use_facet.
+
+      // Cached value from use_facet.
+      const __codecvt_type*	_M_fcvt;       
+      
+      // MT lock inherited from libio or other low-level io library.
       __c_lock          	_M_lock;
-      bool			_M_last_overflowed;  // XXX Needed?
- 
+
+      // XXX Needed? 
+      bool			_M_last_overflowed;  
+  
     public:
       // Constructors/destructor:
       basic_filebuf();
@@ -98,9 +107,13 @@ namespace std {
       close(void);
 
     protected:
-      // Common initialization code for both ctors goes here.
+      // Allocate up pback and internal buffers.
+      void 
+      _M_allocate_buffers();
+
+      // Create __file_type object and initialize it properly.
       void
-      _M_init_filebuf(void);
+      _M_filebuf_init();
 
       // Overridden virtual functions:
       virtual streamsize 
@@ -173,7 +186,7 @@ namespace std {
 	    // (_M_out_beg - _M_out_cur)
 	    streamoff __cur = _M_file->seekoff(0, ios_base::cur);
 	    off_type __off = _M_out_cur - _M_out_beg;
-	    this->_M_really_overflow();
+	    _M_really_overflow();
 	    _M_file->seekpos(__cur + __off);
 	  }
 	_M_last_overflowed = false;	
@@ -183,6 +196,34 @@ namespace std {
       virtual void 
       imbue(const locale& __loc);
 
+      virtual streamsize 
+      xsgetn(char_type* __s, streamsize __n)
+      {
+	streamsize __retval = 0;
+	// Clear out pback buffer before going on to the real deal...
+	if (_M_pback_init)
+	  {
+	    while (__retval < __n && _M_in_cur < _M_in_end)
+	      {
+		*__s = *_M_in_cur;
+		++__retval;
+		++__s;
+		++_M_in_cur;
+	      }
+	    _M_pback_destroy();
+	  }
+	if (__retval < __n)
+	  __retval += __streambuf_type::xsgetn(__s, __n - __retval);
+	return __retval;
+      }
+ 
+      virtual streamsize 
+      xsputn(const char_type* __s, streamsize __n)
+      {
+	_M_pback_destroy();
+	return __streambuf_type::xsputn(__s, __n);
+      }
+       
       void
       _M_output_unshift();
     };
diff --git a/libstdc++-v3/bits/std_sstream.h b/libstdc++-v3/bits/std_sstream.h
index 4394dc90306..343919c68c2 100644
--- a/libstdc++-v3/bits/std_sstream.h
+++ b/libstdc++-v3/bits/std_sstream.h
@@ -64,13 +64,13 @@ namespace std {
       explicit 
       basic_stringbuf(ios_base::openmode __mode = ios_base::in | ios_base::out)
       : __streambuf_type(), _M_string()
-      { _M_init_stringbuf(__mode); }
+      { _M_stringbuf_init(__mode); }
 
       explicit 
       basic_stringbuf(const __string_type& __str,
 		      ios_base::openmode __mode = ios_base::in | ios_base::out)
       : __streambuf_type(), _M_string(__str)
-      { _M_init_stringbuf(__mode); }
+      { _M_stringbuf_init(__mode); }
 
       // Get and set:
       __string_type 
@@ -95,13 +95,13 @@ namespace std {
       str(const __string_type& __s)
       {
 	_M_string = __s;
-	_M_init_stringbuf(_M_mode);
+	_M_stringbuf_init(_M_mode);
       }
 
     protected:
       // Common initialization code for both ctors goes here.
       void
-      _M_init_stringbuf(ios_base::openmode __mode)
+      _M_stringbuf_init(ios_base::openmode __mode)
       {
 	// _M_buf_size is a convenient alias for "what the streambuf
 	// thinks the allocated size of the string really is." This is
diff --git a/libstdc++-v3/bits/std_streambuf.h b/libstdc++-v3/bits/std_streambuf.h
index 23bdd5cca8d..35e214c9123 100644
--- a/libstdc++-v3/bits/std_streambuf.h
+++ b/libstdc++-v3/bits/std_streambuf.h
@@ -98,11 +98,11 @@ namespace std {
       // for an internal buffer.
       // get == input == read
       // put == output == write
-      char_type* 		_M_in_cur;	// Current read area. 
       char_type* 		_M_in_beg;  	// Start of get area. 
+      char_type* 		_M_in_cur;	// Current read area. 
       char_type* 		_M_in_end;	// End of get area. 
-      char_type* 		_M_out_cur;  	// Current put area. 
       char_type* 		_M_out_beg; 	// Start of put area. 
+      char_type* 		_M_out_cur;  	// Current put area. 
       char_type* 		_M_out_end;  	// End of put area. 
 
       // Place to stash in || out || in | out settings for current streambuf.
@@ -117,6 +117,61 @@ namespace std {
       // Cached use_facet<ctype>, which is based on the current locale info.
       const __ctype_type*	_M_buf_fctype;      
 
+      // Necessary bits for putback buffer management. Only used in
+      // the basic_filebuf class, as necessary for the standard
+      // requirements. The only basic_streambuf member function that
+      // needs access to these data members is in_avail...
+      // NB: pbacks of over one character are not currently supported.
+      int_type    		_M_pback_size; 
+      char_type*		_M_pback; 
+      char_type*		_M_pback_cur_save;
+      char_type*		_M_pback_end_save;
+      bool			_M_pback_init; 
+
+      // Initializes pback buffers, and moves normal buffers to safety.
+      // Assumptions:
+      // _M_in_cur has already been moved back
+      void
+      _M_pback_create()
+      {
+	if (!_M_pback_init)
+	  {
+	    int_type __dist = _M_in_end - _M_in_cur;
+	    int_type __len = min(_M_pback_size, __dist);
+	    traits_type::copy(_M_pback, _M_in_cur, __len);
+	    _M_pback_cur_save = _M_in_cur;
+	    _M_pback_end_save = _M_in_end;
+	    this->setg(_M_pback, _M_pback, _M_pback + __len);
+	    _M_pback_init = true;
+	  }
+      }
+
+      // Deactivates pback buffer contents, and restores normal buffer.
+      // Assumptions:
+      // The pback buffer has only moved forward.
+      void
+      _M_pback_destroy()
+      {
+	if (_M_pback_init)
+	  {
+	    // Length _M_in_cur moved in the pback buffer.
+	    int_type __off_cur = _M_in_cur - _M_pback;
+	    
+	    // For in | out buffers, the end can be pushed back...
+	    int_type __off_end = 0;
+	    int_type __pback_len = _M_in_end - _M_pback;
+	    int_type __save_len = _M_pback_end_save - _M_buf;
+	    if (__pback_len > __save_len)
+	      __off_end = __pback_len - __save_len;
+
+	    this->setg(_M_buf, _M_pback_cur_save + __off_cur, 
+		       _M_pback_end_save + __off_end);
+	    _M_pback_cur_save = NULL;
+	    _M_pback_end_save = NULL;
+	    _M_pback_init = false;
+	  }
+      }
+
       // Correctly sets the _M_out_cur pointer, and bumps the
       // appropriate _M_*_end pointers as well. Necessary for the
       // un-tied stringbufs, in in|out mode.
@@ -195,6 +250,7 @@ namespace std {
 	_M_mode = ios_base::openmode(0);
 	_M_buf_fctype = NULL;
 	_M_buf_locale_init = false;
+
       }
 
       // Locales:
@@ -240,7 +296,16 @@ namespace std {
       { 
 	streamsize __retval;
 	if (_M_in_cur && _M_in_cur < _M_in_end)
-	  __retval = this->egptr() - this->gptr();
+	  {
+	    if (_M_pback_init)
+	      {
+		int_type __save_len =  _M_pback_end_save - _M_pback_cur_save;
+		int_type __pback_len = _M_in_cur - _M_pback;
+		__retval = __save_len - __pback_len;
+	      }
+	    else
+	      __retval = this->egptr() - this->gptr();
+	  }
 	else
 	  __retval = this->showmanyc();
 	return __retval;
@@ -289,13 +354,12 @@ namespace std {
     protected:
       basic_streambuf()
       : _M_buf(NULL), _M_buf_size(0), 
-	_M_buf_size_opt(static_cast<int_type>(BUFSIZ * sizeof(char_type))),
-	_M_buf_unified(false), _M_in_cur(0), _M_in_beg(0), _M_in_end(0), 
-	_M_out_cur(0), _M_out_beg(0), _M_out_end(0), 
-	_M_mode(ios_base::openmode(0)), _M_buf_locale(locale()), 
-	_M_buf_locale_init(false) 
-
-      { _M_buf_fctype =  &use_facet<__ctype_type>(this->getloc()); }
+      _M_buf_size_opt(static_cast<int_type>(BUFSIZ)), _M_buf_unified(false), 
+      _M_in_beg(0), _M_in_cur(0), _M_in_end(0), _M_out_beg(0), _M_out_cur(0), 
+      _M_out_end(0), _M_mode(ios_base::openmode(0)), _M_buf_locale(locale()), 
+      _M_buf_locale_init(false), _M_pback_size(1), _M_pback(NULL), 
+      _M_pback_cur_save(NULL), _M_pback_end_save(NULL), _M_pback_init(false)
+      { _M_buf_fctype = &use_facet<__ctype_type>(this->getloc()); }
 
       // Get area:
       char_type* 
diff --git a/libstdc++-v3/src/locale.cc b/libstdc++-v3/src/locale.cc
index 4faa2a40494..15dcf996ca8 100644
--- a/libstdc++-v3/src/locale.cc
+++ b/libstdc++-v3/src/locale.cc
@@ -338,44 +338,44 @@ namespace std {
 	  // (constructor for (*the_classic_locale) adds a third)
 	    
 	  // collate category
-	  _S_classic->_M_init_facet(new std::collate<char>);
+	  _S_classic->_M_facet_init(new std::collate<char>);
 	  
 	  // ctype category
-	  _S_classic->_M_init_facet(new std::ctype<char>);
-	  _S_classic->_M_init_facet(new codecvt<char, char, mbstate_t>);
+	  _S_classic->_M_facet_init(new std::ctype<char>);
+	  _S_classic->_M_facet_init(new codecvt<char, char, mbstate_t>);
 
 	  // monetary category
-	  _S_classic->_M_init_facet(new moneypunct<char, false>);
-	  _S_classic->_M_init_facet(new moneypunct<char,true >);
-	  _S_classic->_M_init_facet(new money_get<char>);
-	  _S_classic->_M_init_facet(new money_put<char>);
+	  _S_classic->_M_facet_init(new moneypunct<char, false>);
+	  _S_classic->_M_facet_init(new moneypunct<char,true >);
+	  _S_classic->_M_facet_init(new money_get<char>);
+	  _S_classic->_M_facet_init(new money_put<char>);
 	  
 	  // numeric category
-	  _S_classic->_M_init_facet(new numpunct<char>);
-	  _S_classic->_M_init_facet(new num_get<char>);
-	  _S_classic->_M_init_facet(new num_put<char>);
+	  _S_classic->_M_facet_init(new numpunct<char>);
+	  _S_classic->_M_facet_init(new num_get<char>);
+	  _S_classic->_M_facet_init(new num_put<char>);
 	  
 	  // time category
-	  _S_classic->_M_init_facet(new time_get<char>);
-	  _S_classic->_M_init_facet(new time_put<char>);
+	  _S_classic->_M_facet_init(new time_get<char>);
+	  _S_classic->_M_facet_init(new time_put<char>);
 	  
 	  // messages category
-	  _S_classic->_M_init_facet(new std::messages<char>);
+	  _S_classic->_M_facet_init(new std::messages<char>);
 
 #ifdef  _GLIBCPP_USE_WCHAR_T
-	  _S_classic->_M_init_facet(new std::collate<wchar_t>);
-	  _S_classic->_M_init_facet(new std::ctype<wchar_t>);
-	  _S_classic->_M_init_facet(new codecvt<wchar_t, char, mbstate_t>);
-	  _S_classic->_M_init_facet(new moneypunct<wchar_t, false>);
-	  _S_classic->_M_init_facet(new moneypunct<wchar_t,true >);
-	  _S_classic->_M_init_facet(new money_get<wchar_t>);
-	  _S_classic->_M_init_facet(new money_put<wchar_t>);
-	  _S_classic->_M_init_facet(new numpunct<wchar_t>);
-	  _S_classic->_M_init_facet(new num_get<wchar_t>);
-	  _S_classic->_M_init_facet(new num_put<wchar_t>);
-	  _S_classic->_M_init_facet(new time_get<wchar_t>);
-	  _S_classic->_M_init_facet(new time_put<wchar_t>);
-	  _S_classic->_M_init_facet(new std::messages<wchar_t>);
+	  _S_classic->_M_facet_init(new std::collate<wchar_t>);
+	  _S_classic->_M_facet_init(new std::ctype<wchar_t>);
+	  _S_classic->_M_facet_init(new codecvt<wchar_t, char, mbstate_t>);
+	  _S_classic->_M_facet_init(new moneypunct<wchar_t, false>);
+	  _S_classic->_M_facet_init(new moneypunct<wchar_t,true >);
+	  _S_classic->_M_facet_init(new money_get<wchar_t>);
+	  _S_classic->_M_facet_init(new money_put<wchar_t>);
+	  _S_classic->_M_facet_init(new numpunct<wchar_t>);
+	  _S_classic->_M_facet_init(new num_get<wchar_t>);
+	  _S_classic->_M_facet_init(new num_put<wchar_t>);
+	  _S_classic->_M_facet_init(new time_get<wchar_t>);
+	  _S_classic->_M_facet_init(new time_put<wchar_t>);
+	  _S_classic->_M_facet_init(new std::messages<wchar_t>);
 #endif	  
 
 	  // finesse static init order hassles
diff --git a/libstdc++-v3/src/localename.cc b/libstdc++-v3/src/localename.cc
index 0af674eea53..200346930c9 100644
--- a/libstdc++-v3/src/localename.cc
+++ b/libstdc++-v3/src/localename.cc
@@ -147,8 +147,8 @@ namespace std {
   locale::_Impl::_M_construct_collate(const char* /*name*/)
   {
 #if 0
-    _M_init_facet(new std::collate_byname<char>(name));
-    _M_init_facet(new std::collate_byname<wchar_t>(name));
+    _M_facet_init(new std::collate_byname<char>(name));
+    _M_facet_init(new std::collate_byname<wchar_t>(name));
 #endif
   }
 
@@ -156,10 +156,10 @@ namespace std {
   locale::_Impl::_M_construct_ctype(const char* /*name*/)
   {
 #if 0
-    _M_init_facet(new std::ctype_byname<char>(name));
-    _M_init_facet(new std::ctype_byname<wchar_t>(name));
-    _M_init_facet(new std::codecvt_byname<char,char,mbstate_t>(name));
-    _M_init_facet(new std::codecvt_byname<wchar_t,char,mbstate_t>(name));
+    _M_facet_init(new std::ctype_byname<char>(name));
+    _M_facet_init(new std::ctype_byname<wchar_t>(name));
+    _M_facet_init(new std::codecvt_byname<char,char,mbstate_t>(name));
+    _M_facet_init(new std::codecvt_byname<wchar_t,char,mbstate_t>(name));
 #endif
   }
     
@@ -167,10 +167,10 @@ namespace std {
   locale::_Impl::_M_construct_monetary(const char* /*name*/)
   {
 #if 0
-    _M_init_facet(new std::moneypunct_byname<char,false>(name));
-    _M_init_facet(new std::moneypunct_byname<wchar_t,false>(name));
-    _M_init_facet(new std::moneypunct_byname<char,true >(name));
-    _M_init_facet(new std::moneypunct_byname<wchar_t,true >(name));
+    _M_facet_init(new std::moneypunct_byname<char,false>(name));
+    _M_facet_init(new std::moneypunct_byname<wchar_t,false>(name));
+    _M_facet_init(new std::moneypunct_byname<char,true >(name));
+    _M_facet_init(new std::moneypunct_byname<wchar_t,true >(name));
 
     locale::_M_initialize();
     _M_replace_facet(locale::_S_classic, &std::money_get<char>(name)::id);
@@ -184,8 +184,8 @@ namespace std {
   locale::_Impl::_M_construct_numeric(const char* /*name*/)
   {
 #if 0
-    _M_init_facet(new std::numpunct_byname<char>(name));
-    _M_init_facet(new std::numpunct_byname<wchar_t>(name));
+    _M_facet_init(new std::numpunct_byname<char>(name));
+    _M_facet_init(new std::numpunct_byname<wchar_t>(name));
 
     locale::_M_initialize();
     _M_replace_facet(locale::_S_classic, &std::num_get<char>::id);
@@ -199,10 +199,10 @@ namespace std {
   locale::_Impl::_M_construct_time(const char* /*name*/)
   {
 #if 0
-    _M_init_facet(new std::time_get_byname<char>(name));
-    _M_init_facet(new std::time_get_byname<wchar_t>(name));
-    _M_init_facet(new std::time_put_byname<char>(name));
-    _M_init_facet(new std::time_put_byname<wchar_t>(name));
+    _M_facet_init(new std::time_get_byname<char>(name));
+    _M_facet_init(new std::time_get_byname<wchar_t>(name));
+    _M_facet_init(new std::time_put_byname<char>(name));
+    _M_facet_init(new std::time_put_byname<wchar_t>(name));
 #endif
   }
     
@@ -210,8 +210,8 @@ namespace std {
   locale::_Impl::_M_construct_messages(const char* /*name*/)
   {
 #if 0
-    _M_init_facet(new std::messages_byname<char>(name));
-    _M_init_facet(new std::messages_byname<wchar_t>(name));
+    _M_facet_init(new std::messages_byname<char>(name));
+    _M_facet_init(new std::messages_byname<wchar_t>(name));
 #endif
   }
 
diff --git a/libstdc++-v3/testsuite/27_io/filebuf-3.tst b/libstdc++-v3/testsuite/27_io/filebuf-3.tst
index d998eef2330..0a81f511290 100644
--- a/libstdc++-v3/testsuite/27_io/filebuf-3.tst
+++ b/libstdc++-v3/testsuite/27_io/filebuf-3.tst
@@ -1,6 +1,6 @@
 bd2
 456x
-9mzuva?@ABCDEFGHIJKLMNOPQRSTUVWXYZracadabras, i wannaz
+9m;uva?@ABCDEFGHIJKLMNOPQRSTUVWXYZracadabras, i wanna 
 because because
 because. . .
 of the wonderful things he does!!
diff --git a/libstdc++-v3/testsuite/27_io/filebuf.cc b/libstdc++-v3/testsuite/27_io/filebuf.cc
index ce51a5915ea..3e0450e388f 100644
--- a/libstdc++-v3/testsuite/27_io/filebuf.cc
+++ b/libstdc++-v3/testsuite/27_io/filebuf.cc
@@ -337,7 +337,7 @@ bool test03() {
   strmsz_1 = fb_03.in_avail();
   c2 = fb_03.sungetc(); // delete the 'a'
   strmsz_2 = fb_03.in_avail();
-  test &= c2 == 'v';
+  test &= c2 == 'v'; //  test &= c2 != traits_type::eof();
   test &= strmsz_1 + 1 == strmsz_2;
   //test for _in_cur == _in_beg
   for (int i = 50; i < 32 + 29; ++i)