freebsd-dev/lib/libc/stdio/refill.c
James Raynard ce51cf0392 Suggested by: Bruce Evans, Jeffrey Hsu, Gary Palmer
Added $Id$'s to files that were lacking them (gpalmer), made some
cosmetic changes to conform to style guidelines (bde) and checked
against NetBSD and Lite2 to remove unnecessary divergences (hsu, bde)

One last code cleanup:-

Removed spurious casts in fseek.c and stdio.c.
Added missing function argument in fwalk.c.
Added missing header include in flags.c and rget.c.
Put in casts where int's were being passed as size_t's.
Put in missing prototypes for static functions.
Changed second args of __sflags() inflags.c and writehook() in vasprintf.c
from char * to const char * to conform to prototypes.

This directory now compiles with no warnings with -Wall under
gcc-2.6.3 and with considerably less warnings than before with the
ultra-pedantic script I used for testing. (Most of the remaining ones
are due to const poisoning).
1996-06-22 10:34:15 +00:00

136 lines
3.9 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)
#if 0
static char sccsid[] = "@(#)refill.c 8.1 (Berkeley) 6/4/93";
#endif
static const char rcsid[] =
"$Id$";
#endif /* LIBC_SCCS and not lint */
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include "local.h"
static int lflush __P((FILE *));
static int
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.
*/
int
__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);
}