glibc/sysdeps/unix/sysv/linux/sparc/sparc64/swapcontext.c

48 lines
1.6 KiB
C

/* Copyright (C) 2001-2020 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Jakub Jelinek <jakub@redhat.com>.
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 restoremask);
int
__swapcontext (ucontext_t *oucp, const ucontext_t *ucp)
{
extern void __swapcontext_ret (void);
/* Save the current machine context to oucp. */
__getcontext (oucp);
/* Modify oucp to skip the __setcontext call on reactivation. */
oucp->uc_mcontext.mc_gregs[MC_PC] = (long) __swapcontext_ret;
oucp->uc_mcontext.mc_gregs[MC_NPC] = ((long) __swapcontext_ret) + 4;
/* Restore the machine context in ucp. */
__setcontext (ucp, 1);
return 0;
}
asm (" \n\
.text \n\
.type __swapcontext_ret, #function \n\
__swapcontext_ret: \n\
return %i7 + 8 \n\
clr %o0 \n\
.size __swapcontext_ret, .-__swapcontext_ret \n\
");
weak_alias (__swapcontext, swapcontext)