git: 9front

ref: ac4840116ef15e2fc65d0e68f7e16d3a8a1aa2f8
dir: /sys/src/cmd/unix/drawterm/libc/frand.c/

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#include	<u.h>
#include	<libc.h>

#define	MASK	0x7fffffffL
#define	NORM	(1.0/(1.0+MASK))

double
frand(void)
{
	double x;

	do {
		x = lrand() * NORM;
		x = (x + lrand()) * NORM;
	} while(x >= 1);
	return x;
}