Fix the handle locking in stdio to use flockfile/funlockfile internally when and where required. Macros in <stdio.h> are updated to automatically call the underlying functions when the process is threaded to obtain the necessary locking. A private mutex is added to protect __sglue, the internal list of FILE handles, and another to protect the one-time initialization. Some routines in libc that use getc() change to use getc_unlocked() as they're either protected by their own lock or aren't thread-safe routines anyway. Based on OpenBSD change by guenther@openbsd.org http://www.mail-archive.com/source-changes@cvs.openbsd.org/msg01015.html Bug: 3446659 Change-Id: Ie82116e358c541718d6709ec45ca6796be5a007b
		
			
				
	
	
		
			67 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			67 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*	$OpenBSD: fwrite.c,v 1.5 2005/08/08 08:05:36 espie Exp $ */
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/*-
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 * Copyright (c) 1990, 1993
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 *	The Regents of the University of California.  All rights reserved.
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 *
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 * This code is derived from software contributed to Berkeley by
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 * Chris Torek.
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 *
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 * Redistribution and use in source and binary forms, with or without
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 * modification, are permitted provided that the following conditions
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 * are met:
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 * 1. Redistributions of source code must retain the above copyright
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 *    notice, this list of conditions and the following disclaimer.
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 * 2. Redistributions in binary form must reproduce the above copyright
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 *    notice, this list of conditions and the following disclaimer in the
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 *    documentation and/or other materials provided with the distribution.
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 * 3. Neither the name of the University nor the names of its contributors
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 *    may be used to endorse or promote products derived from this software
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 *    without specific prior written permission.
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 *
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 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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 * SUCH DAMAGE.
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 */
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#include <stdio.h>
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#include "local.h"
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#include "fvwrite.h"
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/*
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 * Write `count' objects (each size `size') from memory to the given file.
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 * Return the number of whole objects written.
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 */
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size_t
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fwrite(const void *buf, size_t size, size_t count, FILE *fp)
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{
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	size_t n;
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	struct __suio uio;
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	struct __siov iov;
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	int ret;
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	iov.iov_base = (void *)buf;
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	uio.uio_resid = iov.iov_len = n = count * size;
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	uio.uio_iov = &iov;
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	uio.uio_iovcnt = 1;
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	/*
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	 * The usual case is success (__sfvwrite returns 0);
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	 * skip the divide if this happens, since divides are
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	 * generally slow and since this occurs whenever size==0.
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	 */
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	FLOCKFILE(fp);
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	ret = __sfvwrite(fp, &uio);
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	FUNLOCKFILE(fp);
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	if (ret == 0)
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		return (count);
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	return ((n - uio.uio_resid) / size);
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}
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