129 lines
3.8 KiB
C
129 lines
3.8 KiB
C
/*-
|
|
* Copyright (c) 1990, 1993
|
|
* The Regents of the University of California. All rights reserved.
|
|
*
|
|
* This code is derived from software contributed to Berkeley by
|
|
* Chris Torek.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 3. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* This product includes software developed by the University of
|
|
* California, Berkeley and its contributors.
|
|
* 4. Neither the name of the University nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*/
|
|
|
|
#if defined(LIBC_SCCS) && !defined(lint)
|
|
static char sccsid[] = "@(#)refill.c 8.1 (Berkeley) 6/4/93";
|
|
#endif /* LIBC_SCCS and not lint */
|
|
|
|
#include <errno.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include "local.h"
|
|
|
|
static
|
|
lflush(fp)
|
|
FILE *fp;
|
|
{
|
|
|
|
if ((fp->_flags & (__SLBF|__SWR)) == __SLBF|__SWR)
|
|
return (__sflush(fp));
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Refill a stdio buffer.
|
|
* Return EOF on eof or error, 0 otherwise.
|
|
*/
|
|
__srefill(fp)
|
|
register FILE *fp;
|
|
{
|
|
|
|
/* make sure stdio is set up */
|
|
if (!__sdidinit)
|
|
__sinit();
|
|
|
|
fp->_r = 0; /* largely a convenience for callers */
|
|
|
|
/* SysV does not make this test; take it out for compatibility */
|
|
if (fp->_flags & __SEOF)
|
|
return (EOF);
|
|
|
|
/* if not already reading, have to be reading and writing */
|
|
if ((fp->_flags & __SRD) == 0) {
|
|
if ((fp->_flags & __SRW) == 0) {
|
|
errno = EBADF;
|
|
return (EOF);
|
|
}
|
|
/* switch to reading */
|
|
if (fp->_flags & __SWR) {
|
|
if (__sflush(fp))
|
|
return (EOF);
|
|
fp->_flags &= ~__SWR;
|
|
fp->_w = 0;
|
|
fp->_lbfsize = 0;
|
|
}
|
|
fp->_flags |= __SRD;
|
|
} else {
|
|
/*
|
|
* We were reading. If there is an ungetc buffer,
|
|
* we must have been reading from that. Drop it,
|
|
* restoring the previous buffer (if any). If there
|
|
* is anything in that buffer, return.
|
|
*/
|
|
if (HASUB(fp)) {
|
|
FREEUB(fp);
|
|
if ((fp->_r = fp->_ur) != 0) {
|
|
fp->_p = fp->_up;
|
|
return (0);
|
|
}
|
|
}
|
|
}
|
|
|
|
if (fp->_bf._base == NULL)
|
|
__smakebuf(fp);
|
|
|
|
/*
|
|
* Before reading from a line buffered or unbuffered file,
|
|
* flush all line buffered output files, per the ANSI C
|
|
* standard.
|
|
*/
|
|
if (fp->_flags & (__SLBF|__SNBF))
|
|
(void) _fwalk(lflush);
|
|
fp->_p = fp->_bf._base;
|
|
fp->_r = (*fp->_read)(fp->_cookie, (char *)fp->_p, fp->_bf._size);
|
|
fp->_flags &= ~__SMOD; /* buffer contents are again pristine */
|
|
if (fp->_r <= 0) {
|
|
if (fp->_r == 0)
|
|
fp->_flags |= __SEOF;
|
|
else {
|
|
fp->_r = 0;
|
|
fp->_flags |= __SERR;
|
|
}
|
|
return (EOF);
|
|
}
|
|
return (0);
|
|
}
|