random.cpp
488 Bytes
#include <ion.h>
#include <stdlib.h>
uint32_t Ion::random() {
/* rand() returns a pseudo-random integral number in the range between 0 and
* RAND_MAX. We assert that RAND_MAX is at least 8 bit, this way we can merge
* four rand() calls to create a single 32 bit value. Merging is done using
* XOR, whose output is as likely to be a 1 as a 0. */
static_assert(RAND_MAX >= (1<<8), "RAND_MAX is too small");
return (rand() << 24) ^ (rand() << 16) ^ (rand() << 8) ^ rand();
}