31 lines
677 B
C
31 lines
677 B
C
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/*
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* This file is part of the UCB release of Plan 9. It is subject to the license
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* terms in the LICENSE file found in the top-level directory of this
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* distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No
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* part of the UCB release of Plan 9, including this file, may be copied,
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* modified, propagated, or distributed except according to the terms contained
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* in the LICENSE file.
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*/
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#include <u.h>
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#include <libc.h>
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#define MASK 0x7fffffffL
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int
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nrand(int n)
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{
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int32_t slop, v;
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if(n < 0)
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return n;
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if(n == 1)
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return 0;
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/* and if n == 0, you deserve what you get */
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slop = MASK % n;
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do
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v = lrand();
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while(v <= slop);
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return v % n;
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}
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