minix/lib/libc/stdio/fread.c
Lionel Sambuc f14fb60209 Libraries updates and cleanup
* Updating common/lib
 * Updating lib/csu
 * Updating lib/libc
 * Updating libexec/ld.elf_so
 * Corrected test on __minix in featuretest to actually follow the
   meaning of the comment.
 * Cleaned up _REENTRANT-related defintions.
 * Disabled -D_REENTRANT for libfetch
 * Removing some unneeded __NBSD_LIBC defines and tests

Change-Id: Ic1394baef74d11b9f86b312f5ff4bbc3cbf72ce2
2013-01-14 11:36:26 +01:00

94 lines
2.9 KiB
C

/* $NetBSD: fread.c,v 1.22 2012/03/15 18:22:30 christos Exp $ */
/*-
* 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. 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.
*/
#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
static char sccsid[] = "@(#)fread.c 8.2 (Berkeley) 12/11/93";
#else
__RCSID("$NetBSD: fread.c,v 1.22 2012/03/15 18:22:30 christos Exp $");
#endif
#endif /* LIBC_SCCS and not lint */
#include <assert.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include "reentrant.h"
#include "local.h"
size_t
fread(void *buf, size_t size, size_t count, FILE *fp)
{
size_t resid;
char *p;
int r;
size_t total;
_DIAGASSERT(fp != NULL);
/*
* The ANSI standard requires a return value of 0 for a count
* or a size of 0. Whilst ANSI imposes no such requirements on
* fwrite, the SUSv2 does.
*/
if ((resid = count * size) == 0)
return 0;
_DIAGASSERT(buf != NULL);
FLOCKFILE(fp);
if (fp->_r < 0)
fp->_r = 0;
total = resid;
p = buf;
while (resid > (size_t)(r = fp->_r)) {
(void)memcpy(p, fp->_p, (size_t)r);
fp->_p += r;
/* fp->_r = 0 ... done in __srefill */
p += r;
resid -= r;
if (__srefill(fp)) {
/* no more input: return partial result */
FUNLOCKFILE(fp);
return (total - resid) / size;
}
}
(void)memcpy(p, fp->_p, resid);
_DIAGASSERT(__type_fit(int, fp->_r - resid));
fp->_r -= (int)resid;
fp->_p += resid;
FUNLOCKFILE(fp);
return count;
}