contrib/bind-9.5.2/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
  25 typedef 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 */