cdesktopenv/cde/lib/DtMmdb/utility/streambuf.C

155 lines
2.7 KiB
C

/*
* CDE - Common Desktop Environment
*
* Copyright (c) 1993-2012, The Open Group. All rights reserved.
*
* These libraries and programs are free software; you can
* redistribute them and/or modify them under the terms of the GNU
* Lesser General Public License as published by the Free Software
* Foundation; either version 2 of the License, or (at your option)
* any later version.
*
* These libraries and programs are distributed in the hope that
* they will be useful, but WITHOUT ANY WARRANTY; without even the
* implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
* PURPOSE. See the GNU Lesser General Public License for more
* details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with these libraries and programs; if not, write
* to the Free Software Foundation, Inc., 51 Franklin Street, Fifth
* Floor, Boston, MA 02110-1301 USA
*/
/* $XConsortium: streambuf.C /main/8 1996/08/21 15:55:14 drk $ */
#include "utility/c_streambuf.h"
#include <stdlib.h>
#define DEF_BUF_SIZ 4096
streambuf::streambuf() : _size(0), _capacity(DEF_BUF_SIZ), _alloc(1),
_pcount(0), _gcount(0)
{
base = (char*)malloc(DEF_BUF_SIZ);
end = base + DEF_BUF_SIZ;
get_ptr = put_ptr = base;
}
streambuf::streambuf(char* p, int l, int bufferFull) :
base(p), end(p+l), put_ptr(p), get_ptr(p), _size(0), _capacity(l),
_alloc(0), _pcount(0), _gcount(0)
{
if (bufferFull) {
_size = l;
}
}
streambuf::~streambuf()
{
if ( _alloc )
free(base);
}
int streambuf::examine()
{
notify(GET);
if ( empty() && underflow() == EOF )
return EOF;
return (unsigned char)(*get_ptr);
}
int streambuf::get()
{
notify(GET);
if ( empty() && underflow() == EOF )
return EOF;
int x = (unsigned char)(*get_ptr);
move_get_ptr(+1);
_size--;
_gcount++;
return x;
}
int streambuf::putback(char c)
{
if ( full() )
return EOF;
move_get_ptr(-1);
_size++;
*get_ptr = c;
return 0;
}
int streambuf::put(char c)
{
notify(PUT);
if ( full() && overflow() == EOF )
return EOF;
*put_ptr = c;
move_put_ptr(1);
_size++;
_pcount++;
return 0;
}
int streambuf::move_get_ptr(int one)
{
switch (one) {
case 1:
get_ptr++;
if ( get_ptr == end )
get_ptr = base;
return 0;
case -1:
get_ptr--;
if ( get_ptr == base-1 )
get_ptr = end-1;
return 0;
default:
return EOF;
}
}
int streambuf::move_put_ptr(int one)
{
switch (one) {
case 1:
if ( get_ptr == 0 )
get_ptr = put_ptr;
put_ptr++;
if ( put_ptr == end )
put_ptr = base;
return 0;
default:
return EOF;
}
}