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#include <u.h>
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#include <libc.h>
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#include <libsec.h>
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#define Maxrand	((1UL<<31)-1)
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ulong
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nfastrand(ulong n)
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{
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	ulong m, r;
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	/*
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	 * set m to the maximum multiple of n <= 2^31-1
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	 * so we want a random number < m.
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	 */
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	if(n > Maxrand)
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		abort();
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	m = Maxrand - Maxrand % n;
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	while((r = fastrand()) >= m)
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		;
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	return r%n;
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}