23 lines
354 B
C
23 lines
354 B
C
#include "os.h"
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#include <libsec.h>
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#define Maxrand ((1UL<<31)-1)
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uint32_t
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nfastrand(uint32_t n)
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{
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uint32_t 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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jehanne_sysfatal("nfastrand: n too large");
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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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}
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