gcc/libgcc/config/gthr-vxworks.c

88 lines
2.3 KiB
C

/* Copyright (C) 2002-2020 Free Software Foundation, Inc.
Contributed by Zack Weinberg <zack@codesourcery.com>
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.
GCC 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 General Public License
for more details.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>. */
/* Threads compatibility routines for libgcc2 for VxWorks.
This file implements the init-once service exposed by gthr-vxworks.h. */
#include "tconfig.h"
#include "tsystem.h"
#include "gthr.h"
#if defined(__GTHREADS)
#include <vxWorks.h>
#ifndef __RTP__
# include <vxLib.h>
# include <taskHookLib.h>
#else /* __RTP__ */
# include <errno.h>
#endif /* __RTP__ */
/* ----------------------------- Init-once ------------------------------- */
static void
__release (__gthread_once_t ** __guard)
{
(*__guard)->busy = 0;
}
int
__gthread_once (__gthread_once_t * __guard, void (*__func) (void))
{
if (__guard->done)
return 0;
/* Busy-wait until we have exclusive access to the state. Check if
another thread managed to perform the init call in the interim. */
while (!__TAS(&__guard->busy))
{
if (__guard->done)
return 0;
taskDelay (1);
}
if (!__guard->done)
{
#ifndef __USING_SJLJ_EXCEPTIONS__
/* Setup a cleanup to release the guard when __func() throws an
exception. We cannot use this with SJLJ exceptions as
Unwind_Register calls __gthread_once, leading to an infinite
recursion. */
__attribute__ ((cleanup (__release)))
__gthread_once_t *__temp = __guard;
#endif
__func ();
__guard->done = 1;
}
__release(&__guard);
return 0;
}
#endif /* __GTHREADS */