filbuf.c

来自「su 的源代码库」· C语言 代码 · 共 56 行

/* Copyright (c) Colorado School of Mines, 2006.*/
/* All rights reserved.                       */

#define _in_filbuf	1
#include	"sfstdio.h"

/*	Fill buffer.
**	Written by Kiem-Phong Vo.
*/

FILBUF(f)
{
	reg Sfio_t*	sf;
	reg int		rv;

	if(!(sf = _sfstream(f)))
		return -1;

	if((rv = sfgetc(sf)) < 0)
		_stdseterr(f,sf);
	else if(!(sf->flags&SF_MTSAFE) )
	{
#if _FILE_readptr	/* Linux-stdio */
#if _under_flow && !_u_flow	/* __underflow does not bump pointer */
		f->std_readptr = sf->next-1;
#else
		f->std_readptr = sf->next;
#endif
		f->std_readend = sf->endb;
#endif
#if _FILE_writeptr
		f->std_writeptr = f->std_writeend = NIL(uchar*);
#endif

#if _FILE_ptr || _FILE_p	/* old/BSD-stdio */
		f->std_ptr = sf->next;
#endif
#if _FILE_cnt
		f->std_cnt = sf->endb - sf->next;
#endif
#if _FILE_r
		f->std_r = sf->endb - sf->next;
#endif
#if _FILE_w
		f->std_w = 0;
#endif

#if _FILE_readptr || _FILE_cnt || _FILE_r
		sf->mode |= SF_STDIO;
		sf->endr = sf->endw = sf->data;
#endif
	}

	return(rv);
}