/*

  * Copyright (c) 1999

  * Silicon Graphics Computer Systems, Inc.

  *

  * Copyright (c) 1999

  * Boris Fomitchev

  *

  * This material is provided "as is", with absolutely no warranty expressed

  * or implied. Any use is at your own risk.

  *

  * Permission to use or copy this software for any purpose is hereby granted

  * without fee, provided the above notices are retained on all copies.

  * Permission to modify the code and to distribute modified code is granted,

  * provided the above notices are retained, and a notice that the code was

  * modified is included with the above copyright notice.

  *

  */

 // This header is an extension.  It defines two streambufs:

 // stdio_istreambuf, a read-only streambuf synchronized with a C stdio

 // FILE object, and stdio_ostreambuf, a write-only streambuf

 // synchronized with a C stdio FILE object.  Note that neither

 // stdio_istreambuf nor stdio_ostreambuf is a template; both classes

 // are derived from basic_streambuf<char, char_traits<char> >.

 // Note: the imbue() member function is a no-op.  In particular, these

 // classes assume that codecvt<char, char, mbstate_t> is always an identity

 // transformation.  This is true of the default locale, and of all locales

 // defined for the C I/O library.  If you need to use a locale where

 // the codecvt<char, char, mbstate_t> facet performs a nontrivial

 // conversion, then you should use basic_filebuf<> instead of stdio_istreambuf

 // or stdio_ostreambuf.  (If you don't understand what any of this means,

 // then it's not a feature you need to worry about.  Locales where

 // codecvt<char, char, mbstate_t> does something nontrivial are a rare

 // corner case.)

 #ifndef _STLP_STDIO_STREAMBUF

 #define _STLP_STDIO_STREAMBUF

 #include <streambuf>

 #include <cstdio>              // For FILE.

 _STLP_BEGIN_NAMESPACE

 _STLP_MOVE_TO_PRIV_NAMESPACE

 // Base class for features common to stdio_istreambuf and stdio_ostreambuf

 class stdio_streambuf_base :

   public basic_streambuf<char, char_traits<char> > /* FILE_basic_streambuf */ {

 public:                         // Constructor, destructor.

   // The argument may not be null.  It must be an open file pointer.

   stdio_streambuf_base(FILE*);

   // The destructor flushes the stream, but does not close it.

   ~stdio_streambuf_base();

 protected:                      // Virtual functions from basic_streambuf.

   streambuf* setbuf(char*, streamsize);

   pos_type seekoff(off_type, ios_base::seekdir,

                    ios_base::openmode

                           = ios_base::in | ios_base::out);

   pos_type seekpos(pos_type,

                    ios_base::openmode

                           = ios_base::in | ios_base::out);

   int sync();

 protected:

   FILE* _M_file;

 };

 class stdio_istreambuf : public stdio_streambuf_base {

 public:                         // Constructor, destructor.

   stdio_istreambuf(FILE* __f) : stdio_streambuf_base(__f) {}

   ~stdio_istreambuf();

 protected:                      // Virtual functions from basic_streambuf.

   streamsize showmanyc();

   int_type underflow();

   int_type uflow();

   virtual int_type pbackfail(int_type c = traits_type::eof());

 };

 class stdio_ostreambuf : public stdio_streambuf_base {

 public:                         // Constructor, destructor.

   stdio_ostreambuf(FILE* __f) : stdio_streambuf_base(__f) {}

   ~stdio_ostreambuf();

 protected:                      // Virtual functions from basic_streambuf.

   streamsize showmanyc();

   int_type overflow(int_type c = traits_type::eof());

 };

 _STLP_MOVE_TO_STD_NAMESPACE

 _STLP_END_NAMESPACE

 #endif /* _STLP_STDIO_STREAMBUF */

 // Local Variables:

 // mode:C++

 // End: