Xorshift Generation

A good and easy alternative to the flawed rand() procedures, is xorshift, a class of pseudo-random number generators discovered by George Marsaglia. The xorshift generator is among the fastest non-cryptographically-secure random number generators. More information and other example implementaions are available on the xorshift Wikipedia page

Example implementation

#include <stdint.h>

/* These state variables must be initialised so that they are not all zero. */
uint32_t w, x, y, z;

uint32_t xorshift128(void) 
{
    uint32_t t = x;
    t ^= t << 11U;
    t ^= t >> 8U;
    x = y; y = z; z = w;
    w ^= w >> 19U;
    w ^= t;
    return w;
}