freebsd-nq/lib/libstdthreads/call_once.c
Ed Schouten fc6f0665ba Add libstdthreads.
This library implements the C11 threads interface on top of the pthreads
library.  As discussed on the lists, the preferred way to implement
this, is as a separate library.

It is unlikely that these functions will be used a lot in the future. It
would have been easier if the C11 working group standardized (a subset
of) pthreads and clock_nanosleep(). Having it as a separate library
allows the embedded people to omit it from their system.

Discussed on:	arch@, threads@
2011-12-26 21:51:53 +00:00

45 lines
1.7 KiB
C

/*-
* Copyright (c) 2011 Ed Schouten <ed@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <pthread.h>
#include "threads.h"
void
call_once(once_flag *flag, void (*func)(void))
{
(void)pthread_once((pthread_once_t *)flag, func);
}
_Static_assert(sizeof(once_flag) == sizeof(pthread_once_t),
"once_flag must be of the same size as pthread_once_t");