glibc/sysdeps/unix/sysv/linux/hppa/swapcontext.c

43 lines
1.4 KiB
C

/* Swap to new context.
Copyright (C) 2008-2020 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Helge Deller <deller@gmx.de>, 2008.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library. If not, see
<https://www.gnu.org/licenses/>. */
#include <ucontext.h>
extern int __getcontext (ucontext_t *ucp);
extern int __setcontext (const ucontext_t *ucp);
int
__swapcontext (ucontext_t *oucp, const ucontext_t *ucp)
{
/* Save the current machine context to oucp. */
__getcontext (oucp);
/* mark sc_sar flag to skip the setcontext call on reactivation. */
if (oucp->uc_mcontext.sc_sar == 0) {
oucp->uc_mcontext.sc_sar++;
/* Restore the machine context in ucp. */
__setcontext (ucp);
}
return 0;
}
weak_alias (__swapcontext, swapcontext)