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| | #define _BSD_SOURCE
#include <unistd.h>
#include <sys/random.h>
#include <pthread.h>
#include <errno.h>
int getentropy(void *buffer, size_t len)
{
int cs, ret;
char *pos = buffer;
if (len > 256) {
errno = EIO;
return -1;
}
pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
while (len) {
ret = getrandom(pos, len, 0);
if (ret <= 0) {
if (errno == EINTR) continue;
else break;
}
pos += ret;
len -= ret;
}
pthread_setcancelstate(cs, 0);
if (len) {
errno = EIO;
return -1;
}
return 0;
}
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