genericopenlibs/openenvcore/libc/src/stdio/fread.c
author Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
Wed, 13 Oct 2010 16:27:53 +0300
branchRCL_3
changeset 75 254b651f304e
parent 0 e4d67989cc36
permissions -rw-r--r--
Revision: 201039 Kit: 201041

/*-
 * 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.
 * 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.
 * * Portions Copyright (c) 2005-2009 Nokia Corporation and/or its subsidiary(-ies). All rights reserved. 
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)fread.c	8.2 (Berkeley) 12/11/93";
#endif /* LIBC_SCCS and not lint */
#include <sys/cdefs.h>
#ifndef __SYMBIAN32__
__FBSDID("$FreeBSD: src/lib/libc/stdio/fread.c,v 1.12 2002/10/12 16:13:37 mike Exp $");
#endif
#include "namespace.h"
#include <stdio.h>
#include <string.h>
#include "un-namespace.h"
#include "local.h"
#include "libc_private.h"

EXPORT_C size_t
fread(void * __restrict buf, size_t size, size_t count, FILE * __restrict fp)	
{
	
	int r;
	size_t total;
	char *p;
	size_t resid;
	
	#ifdef __SYMBIAN32__
	if (fp->_bf._base == NULL)
	{
		__smakebuf(fp);
		if(fp->_bf._base == NULL && errno == ENOMEM)
		{
			return (EOF);
		}
	}
	#endif
	
	/*
	 * The ANSI standard requires a return value of 0 for a count
	 * or a size of 0.  Peculiarily, it imposes no such requirements
	 * on fwrite; it only requires fread to be broken.
	 */
	if ((resid = count * size) == 0)
		return (0);
	FLOCKFILE(fp);
	ORIENT(fp, -1);
	if (fp->_r < 0)
		fp->_r = 0;
	total = resid;
	p = buf;
	while (resid > (r = fp->_r)) {
		(void)memcpy((void *)p, (void *)fp->_p, (size_t)r);
		fp->_p += r;
		/* fp->_r = 0 ... done in __srefill */
		p += r;
		resid -= r;
		if( resid >= fp->_bf._size ){
			if (__read_long(fp,p,&resid)) {
				/* no more input: return partial result */
				FUNLOCKFILE(fp);
				return ((total - resid) / size);
			}
		}
		else{
			if (__srefill(fp)) {
			/* no more input: return partial result */
			FUNLOCKFILE(fp);
			return ((total - resid) / size);
			}
		}
	}
	(void)memcpy((void *)p, (void *)fp->_p, resid);
	fp->_r -= resid;
	fp->_p += resid;
	FUNLOCKFILE(fp);
	return (count);
}