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/* taken from nacl-20110221, from randombytes/devurandom.c, added close-on-exec */
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include "randombytes.h"
/* it's really stupid that there isn't a syscall for this */
static int fd = -1;
void randombytes(unsigned char *x,unsigned long long xlen)
{
int i;
if (fd == -1) {
for (;;) {
#ifdef O_CLOEXEC
fd = open("/dev/urandom",O_RDONLY | O_CLOEXEC);
#else
fd = open("/dev/urandom",O_RDONLY);
fcntl(fd,F_SETFD,1);
#endif
if (fd != -1) break;
sleep(1);
}
}
while (xlen > 0) {
if (xlen < 1048576) i = xlen; else i = 1048576;
i = read(fd,x,i);
if (i < 1) {
sleep(1);
continue;
}
x += i;
xlen -= i;
}
}
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