kolibrios/programs/develop/open watcom/trunk/clib/streamio/ioalloc.c
Sergey Semyonov (Serge) 3be3768ce0 update CLib
git-svn-id: svn://kolibrios.org@614 a494cfbc-eb01-0410-851d-a64ba20cac60
2007-08-28 10:31:46 +00:00

69 lines
2.6 KiB
C

/****************************************************************************
*
* Open Watcom Project
*
* Portions Copyright (c) 1983-2002 Sybase, Inc. All Rights Reserved.
*
* ========================================================================
*
* This file contains Original Code and/or Modifications of Original
* Code as defined in and that are subject to the Sybase Open Watcom
* Public License version 1.0 (the 'License'). You may not use this file
* except in compliance with the License. BY USING THIS FILE YOU AGREE TO
* ALL TERMS AND CONDITIONS OF THE LICENSE. A copy of the License is
* provided with the Original Code and Modifications, and is also
* available at www.sybase.com/developer/opensource.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND SYBASE AND ALL CONTRIBUTORS HEREBY DISCLAIM
* ALL SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR
* NON-INFRINGEMENT. Please see the License for the specific language
* governing rights and limitations under the License.
*
* ========================================================================
*
* Description: Platform independent __ioalloc() implementation.
*
****************************************************************************/
#include "variety.h"
#include <stdio.h>
#include "liballoc.h"
#include <unistd.h>
#include "rtdata.h"
#include "streamio.h"
void __ioalloc( FILE *fp )
{
__chktty( fp ); /* JBS 28-aug-90 */
if( fp->_bufsize == 0 ) {
if( fp->_flag & _IOLBF ) {
fp->_bufsize = 134;
} else if( fp->_flag & _IONBF ) {
/* Use small but reasonably sized buffer; otherwise we will end
* up calling into the OS for every character, completely killing
* performance on unbuffered stream output through printf() etc.,
* especially in extended DOS because of mode switches.
*/
fp->_bufsize = 64;
} else {
fp->_bufsize = BUFSIZ;
}
}
_FP_BASE(fp) = lib_malloc( fp->_bufsize );
if( _FP_BASE(fp) == NULL ) {
fp->_flag &= ~(_IONBF | _IOLBF | _IOFBF);
fp->_flag |= _IONBF; /* can't get big buffer */
_FP_BASE(fp) = (char *)&(fp->_ungotten);
fp->_bufsize = 1;
} else {
fp->_flag |= _BIGBUF; /* got big buffer */
}
fp->_ptr = _FP_BASE(fp);
fp->_cnt = 0;
}