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/* See LICENSE file for copyright and license details. */
#include "common.h"
#ifndef TEST
#include <sys/auxv.h>
unsigned int
libsimple_generate_seed(void) /* TODO add test */
{
uintptr_t longseed = 1;
void *ptr;
uintptr_t ptri;
unsigned int seed;
struct timespec ts;
uint8_t (*at_random)[16];
size_t i;
if (!clock_gettime(CLOCK_REALTIME, &ts))
longseed ^= (uintptr_t)ts.tv_sec * (uintptr_t)1000000000UL + (uintptr_t)ts.tv_nsec;
ptr = malloc(1);
ptri = (uintptr_t)ptr;
free(ptr);
longseed ^= ptri;
longseed ^= (uintptr_t)&ptri;
longseed ^= (uintptr_t)clock();
if (!clock_gettime(CLOCK_MONOTONIC_RAW, &ts))
longseed ^= (uintptr_t)ts.tv_sec * (uintptr_t)1000000000UL + (uintptr_t)ts.tv_nsec;
ptri = (uintptr_t)getauxval(AT_RANDOM);
if (ptri) {
at_random = (void *)ptri;
for (i = 0; i < ELEMSOF(*at_random); i++)
longseed ^= (*at_random)[i] << (i % sizeof(longseed) * (size_t)CHAR_BIT);
}
seed = 0;
while (longseed) {
seed ^= (unsigned int)longseed;
longseed >>= sizeof(unsigned int) * (CHAR_BIT - 1);
longseed >>= sizeof(unsigned int);
}
return seed;
}
#else
#include "test.h"
int
main(void)
{
return 0;
}
#endif
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