/contrib/bind9/lib/isc/nothreads/include/isc/once.h

 1/*
 2 * Copyright (C) 2004, 2007  Internet Systems Consortium, Inc. ("ISC")
 3 * Copyright (C) 2000, 2001  Internet Software Consortium.
 4 *
 5 * Permission to use, copy, modify, and/or distribute this software for any
 6 * purpose with or without fee is hereby granted, provided that the above
 7 * copyright notice and this permission notice appear in all copies.
 8 *
 9 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
10 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
11 * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
12 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
13 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
14 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
15 * PERFORMANCE OF THIS SOFTWARE.
16 */
17
18/* $Id: once.h,v 1.6 2007/06/19 23:47:18 tbox Exp $ */
19
20#ifndef ISC_ONCE_H
21#define ISC_ONCE_H 1
22
23#include <isc/result.h>
24
25typedef isc_boolean_t isc_once_t;
26
27#define ISC_ONCE_INIT ISC_FALSE
28
29#define isc_once_do(op, f) \
30	(!*(op) ? (f(), *(op) = ISC_TRUE, ISC_R_SUCCESS) : ISC_R_SUCCESS)
31
32#endif /* ISC_ONCE_H */