glibc/sunrpc/create_xid.c

55 lines
1.6 KiB
C

/* Copyright (c) 1998, 2000 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Thorsten Kukuk <kukuk@vt.uni-paderborn.de>, 1998.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <unistd.h>
#include <stdlib.h>
#include <sys/time.h>
#include <bits/libc-lock.h>
#include <rpc/rpc.h>
/* The RPC code is not threadsafe, but new code should be threadsafe. */
__libc_lock_define_initialized (static, createxid_lock)
static int is_initialized;
static struct drand48_data __rpc_lrand48_data;
unsigned long
_create_xid (void)
{
unsigned long res;
__libc_lock_lock (createxid_lock);
if (!is_initialized)
{
struct timeval now;
__gettimeofday (&now, (struct timezone *) 0);
__srand48_r (now.tv_sec ^ now.tv_usec, &__rpc_lrand48_data);
is_initialized = 1;
}
lrand48_r (&__rpc_lrand48_data, &res);
__libc_lock_unlock (createxid_lock);
return res;
}