DataMuseum.dk

top - metrics - download

    Length: 4849 (0x12f1)
    Types: TextFile
    Names: »streambuf.h«

└─⟦a05ed705a⟧ Bits:30007078 DKUUG GNU 2/12/89
    └─⟦cc8755de2⟧ »./libg++-1.36.1.tar.Z« 
        └─⟦23757c458⟧ 
            └─⟦this⟧ »libg++/g++-include/streambuf.h« 

TextFile

// This may look like C code, but it is really -*- C++ -*-
/* 
Copyright (C) 1988 Free Software Foundation
    written by Doug Lea (dl@rocky.oswego.edu)

This file is part of GNU CC.

GNU CC is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY.  No author or distributor
accepts responsibility to anyone for the consequences of using it
or for whether it serves any particular purpose or works at all,
unless he says so in writing.  Refer to the GNU CC General Public
License for full details.

Everyone is granted permission to copy, modify and redistribute
GNU CC, but only under the conditions described in the
GNU CC General Public License.   A copy of this license is
supposed to have been given to you along with GNU CC so you
can know your rights and responsibilities.  It should be in a
file named COPYING.  Among other things, the copyright notice
and this notice must be preserved on all copies.  
*/

#ifndef _streambuf_h
#pragma once
#define _streambuf_h 1

/* streambufs. 
   basic streambufs and filebufs are as in Stroustrup, ch 8,
   but the base class contains virtual extensions that allow
   most capabilities of libg++ Files to be used as streambufs
   via `Filebufs'.
*/

#include <builtin.h>
#include <stdio.h>
#include <File.h>

#ifndef BUFSIZE
#ifdef BUFSIZ
#define BUFSIZE BUFSIZ
#else
#define BUFSIZE 1024
#endif
#endif

enum open_mode // filebuf open modes
{ 
  input=0, 
  output=1, 
  append=2 
}; 

class streambuf
{
public:
  char*       base;          // start of buffer
  char*       pptr;          // put-pointer (and gptr fence)
  char*       gptr;          // get-pointer
  char*       eptr;          // fence

  char        alloc;         // true if we own freestore alloced buffer

              streambuf();
              streambuf(char* buf, int buflen);
 
  virtual    ~streambuf();

  int         doallocate();
  int         allocate();


  virtual int overflow(int c = EOF); // flush -- return EOF if fail
  virtual int underflow();           // fill -- return EOF if fail

  int         sgetc();          // get one char (as int) or EOF
  int         snextc();         // get and advance
  void        stossc();         // advance only

  int         sputback(char);   // unget

  int         sputc(int c = EOF);             // write one char

  virtual streambuf*  setbuf(char* buf, int buflen, int preloaded_count = 0);
                                // (not virtual in AT&T)

// the following aren't in AT&T version:

  int         sputs(const char* s);           // write null-terminated str
  int         sputsn(const char* s, int len); // write len bytes

  virtual const char* name();


  virtual streambuf*  open(const char* name, open_mode m);
  virtual streambuf*  open(const char* filename, io_mode m, access_mode a);
  virtual streambuf*  open(const char* filename, const char* m);
  virtual streambuf*  open(int  filedesc, io_mode m);
  virtual streambuf*  open(FILE* fileptr);

  virtual int         is_open();
  virtual int         close();

  virtual void        error();
};


class filebuf: public streambuf
{
public:
  int         fd;
  char        opened;

  int         overflow(int c = EOF);
  int         underflow();

              filebuf();
              filebuf(int newfd);
              filebuf(int newfd, char* buf, int buflen);

             ~filebuf();

  streambuf*  open(const char* name, open_mode m);
  int         is_open();
  int         close();
};

class Filebuf: public streambuf // libg++ File version
{
public:
  File*       Fp;

  void        init_streambuf_ptrs();

  int         overflow(int c = EOF);
  int         underflow();

              Filebuf();
              Filebuf(const char* filename, io_mode m, access_mode a);
              Filebuf(const char* filename, const char* m);   
              Filebuf(int filedesc, io_mode m);
              Filebuf(FILE* fileptr);
  
             ~Filebuf();

  const char* name();
  streambuf*  setbuf(char* buf, int buflen, int preloaded_count = 0);

  streambuf*  open(const char* filename, io_mode m, access_mode a);
  streambuf*  open(const char* filename, const char* m);
  streambuf*  open(int  filedesc, io_mode m);
  streambuf*  open(FILE* fileptr);

  int         is_open();
  int         close();

  void        error();
};


inline int streambuf::allocate()
{
  return (base == 0)? doallocate() : 0; 
}

inline int streambuf::sgetc()
{
  return (gptr >= pptr)? underflow() : int(*gptr);
}


inline int streambuf::snextc()
{
  ++gptr;
  return (gptr >= pptr)? underflow() : int(*gptr);
}


inline void streambuf::stossc()
{
  if (gptr >= pptr) underflow(); else gptr++;
}


inline int streambuf::sputback(char ch)
{
  return (gptr > base)? (*--gptr = ch) : EOF;
}

inline int streambuf::sputc(int ch = EOF)
{
  return (pptr < eptr)? (*pptr++ = (char)(ch)) : overflow(ch);
}

#endif