1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
|
#include <stdint.h>
#include <stdio.h>
#include <sys/time.h>
#include <sys/types.h>
#include <time.h>
#include <unistd.h>
uint64_t hs_hashable_init() {
/* if there is /dev/urandom, read from it */
FILE *urandom = fopen("/dev/urandom", "r");
if (urandom) {
uint64_t result = 0;
size_t r = fread(&result, sizeof(uint64_t), 1, urandom);
fclose(urandom);
if (r == 1) {
return result;
} else {
return 0xfeed1000;
}
} else {
/* time of day */
struct timeval tp = {0, 0};
gettimeofday(&tp, NULL);
/* cputime */
clock_t c = clock();
/* process id */
pid_t p = getpid();
return ((uint64_t) tp.tv_sec)
^ ((uint64_t) tp.tv_usec)
^ ((uint64_t) c << 16)
^ ((uint64_t) p << 32);
}
}
|
