kitty/kitty/cross-platform-random.h
2020-12-31 11:26:22 +05:30

36 lines
783 B
C

/*
* Copyright (C) 2020 Kovid Goyal <kovid at kovidgoyal.net>
*
* Distributed under terms of the GPL3 license.
*/
#pragma once
#include <stdlib.h>
#include <stdbool.h>
#if __linux__
#include <sys/random.h>
#include <errno.h>
static inline bool
secure_random_bytes(void *buf, size_t nbytes) {
unsigned char* p = buf;
ssize_t left = nbytes;
while(1) {
ssize_t n = getrandom(p, left, 0);
if (n >= left) return true;
if (n < 0) {
if (errno != EINTR) return false; // should never happen but if it does, we fail without any feedback
continue;
}
left -= n; p += n;
}
}
#else
static inline bool
secure_random_bytes(void *buf, size_t nbytes) {
arc4random_buf(buf, nbytes);
return true;
}
#endif