1 /* Copyright (C) 2001 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Jakub Jelinek <jakub@redhat.com>.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, write to the Free
17 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
25 extern int __getcontext (ucontext_t *ucp);
26 extern int __setcontext (const ucontext_t *ucp, int restoremask);
29 swapcontext (ucontext_t *oucp, const ucontext_t *ucp)
31 extern void __swapcontext_ret (void);
32 /* Save the current machine context to oucp. */
34 /* Modify oucp to skip the __setcontext call on reactivation. */
35 *(long*)((char*)oucp+UC_M_PC) = (long)__swapcontext_ret;
36 *(long*)((char*)oucp+UC_M_NPC) = (long)__swapcontext_ret + 4;
37 /* Restore the machine context in ucp. */
38 __setcontext (ucp, 1);
44 .type __swapcontext_ret, #function \n\
45 __swapcontext_ret: \n\
48 .size __swapcontext_ret, .-__swapcontext_ret \n\