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cwfs: remove orphaned lrand.c

--- a/sys/src/cmd/cwfs/lrand.c

+++ /dev/null

@@ -1,83 +1,0 @@

-#include "all.h"

-

-/*

- *	algorithm by

- *	D. P. Mitchell & J. A. Reeds

- */

-enum {

-	LEN	= 607,

-	TAP	= 273,

-	MASK	= 0x7fffffffL,

-	A	= 48271,

-	M	= 2147483647,

-	Q	= 44488,

-	R	= 3399,

-};

-

-#define	NORM	(1.0/(1.0+MASK))

-

-static	ulong	rng_vec[LEN];

-static	ulong*	rng_tap = rng_vec;

-static	ulong*	rng_feed = 0;

-static	Lock	lk;

-

-static void

-isrand(long seed)

-{

-	long lo, hi, x;

-	int i;

-

-	rng_tap = rng_vec;

-	rng_feed = rng_vec+LEN-TAP;

-	seed %= M;

-	if(seed < 0)

-		seed += M;

-	if(seed == 0)

-		seed = 89482311;

-	x = seed;

-	/*

-	 *	Initialize by x[n+1] = 48271 * x[n] mod (2**31 - 1)

-	 */

-	for(i = -20; i < LEN; i++) {

-		hi = x / Q;

-		lo = x % Q;

-		x = A*lo - R*hi;

-		if(x < 0)

-			x += M;

-		if(i >= 0)

-			rng_vec[i] = x;

-	}

-}

-

-void

-srand(long seed)

-{

-	lock(&lk);

-	isrand(seed);

-	unlock(&lk);

-}

-

-long

-lrand(void)

-{

-	ulong x;

-

-	lock(&lk);

-

-	rng_tap--;

-	if(rng_tap < rng_vec) {

-		if(rng_feed == 0) {

-			isrand(1);

-			rng_tap--;

-		}

-		rng_tap += LEN;

-	}

-	rng_feed--;

-	if(rng_feed < rng_vec)

-		rng_feed += LEN;

-	x = (*rng_feed + *rng_tap) & MASK;

-	*rng_feed = x;

-

-	unlock(&lk);

-	return x;

-}

-- 

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