/*
 * Copyright 2023, Haiku, Inc. All rights reserved.
 * Distributed under the terms of the MIT License.
 */

#include <unistd.h>

#include <errno_private.h>
#include <random_defs.h>
#include <syscall_utils.h>
#include <syscalls.h>


int
getentropy(void *buf, size_t buflen)
{
        if (buflen > GETENTROPY_MAX)
                RETURN_AND_SET_ERRNO(EINVAL);

        while (buflen > 0) {
                status_t status;
                struct random_get_entropy_args args;
                args.buffer = buf;
                args.length = buflen;

                status = _kern_generic_syscall(RANDOM_SYSCALLS, RANDOM_GET_ENTROPY,
                        &args, sizeof(args));
                if (status == EINTR)
                        continue;
                if (status < 0)
                        RETURN_AND_SET_ERRNO(status);

                buf = (char*)buf + args.length;
                buflen -= args.length;
        }

        return 0;
}