GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libc/stdlib/rand.c Lines: 9 10 90.0 %
Date: 2017-11-07 Branches: 2 2 100.0 %

Line Branch Exec Source
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/*	$OpenBSD: rand.c,v 1.17 2016/10/22 19:19:34 tb Exp $ */
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/*-
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 * Copyright (c) 1990 The Regents of the University of California.
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 * All rights reserved.
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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 <sys/types.h>
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#include <stdlib.h>
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static int rand_deterministic;
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static u_int next = 1;
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int
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rand_r(u_int *seed)
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{
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	*seed = *seed * 1103515245 + 12345;
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	return (*seed & RAND_MAX);
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}
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DEF_WEAK(rand_r);
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#if defined(APIWARN)
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__warn_references(rand_r,
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    "warning: rand_r() is not random, it is deterministic.");
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#endif
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int
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rand(void)
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{
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	if (rand_deterministic == 0)
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		return (arc4random() & RAND_MAX);
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	return (rand_r(&next));
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}
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#if defined(APIWARN)
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__warn_references(rand,
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    "warning: rand() may return deterministic values, is that what you want?");
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#endif
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void
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srand(u_int seed)
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{
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	rand_deterministic = 0;
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}
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void
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srand_deterministic(u_int seed)
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{
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	rand_deterministic = 1;
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	next = seed;
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}