dist/ntp/include/isc/once.h

   1 /*      $NetBSD$        */
   2
   3 /*
   4  * Copyright (C) 2000, 2001  Internet Software Consortium.
   5  *
   6  * Permission to use, copy, modify, and distribute this software for any
   7  * purpose with or without fee is hereby granted, provided that the above
   8  * copyright notice and this permission notice appear in all copies.
   9  *
  10  * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM
  11  * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
  12  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
  13  * INTERNET SOFTWARE CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT,
  14  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
  15  * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
  16  * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
  17  * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  18  */
  19
  20 /* Id: once.h,v 1.3 2001/01/09 21:57:56 bwelling Exp */
  21
  22 #ifndef ISC_ONCE_H
  23 #define ISC_ONCE_H 1
  24
  25 #include <isc/result.h>
  26
  27 typedef isc_boolean_t isc_once_t;
  28
  29 #define ISC_ONCE_INIT ISC_FALSE
  30
  31 #define isc_once_do(op, f) \
  32         (!*(op) ? (f(), *(op) = ISC_TRUE, ISC_R_SUCCESS) : ISC_R_SUCCESS)
  33
  34 #endif /* ISC_ONCE_H */