1 41b3e8b9 2020-01-20 rsc /* Copyright (C) 2001 Free Software Foundation, Inc.
 2 41b3e8b9 2020-01-20 rsc    This file is part of the GNU C Library.
 3 41b3e8b9 2020-01-20 rsc    Contributed by Jakub Jelinek <jakub@redhat.com>.
 4 41b3e8b9 2020-01-20 rsc 
 5 41b3e8b9 2020-01-20 rsc    The GNU C Library is free software; you can redistribute it and/or
 6 41b3e8b9 2020-01-20 rsc    modify it under the terms of the GNU Lesser General Public
 7 41b3e8b9 2020-01-20 rsc    License as published by the Free Software Foundation; either
 8 41b3e8b9 2020-01-20 rsc    version 2.1 of the License, or (at your option) any later version.
 9 41b3e8b9 2020-01-20 rsc 
10 41b3e8b9 2020-01-20 rsc    The GNU C Library is distributed in the hope that it will be useful,
11 41b3e8b9 2020-01-20 rsc    but WITHOUT ANY WARRANTY; without even the implied warranty of
12 41b3e8b9 2020-01-20 rsc    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13 41b3e8b9 2020-01-20 rsc    Lesser General Public License for more details.
14 41b3e8b9 2020-01-20 rsc 
15 41b3e8b9 2020-01-20 rsc    You should have received a copy of the GNU Lesser General Public
16 41b3e8b9 2020-01-20 rsc    License along with the GNU C Library; if not, write to the Free
17 41b3e8b9 2020-01-20 rsc    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
18 41b3e8b9 2020-01-20 rsc    02111-1307 USA.  */
19 41b3e8b9 2020-01-20 rsc 
20 41b3e8b9 2020-01-20 rsc #include <ucontext.h>
21 41b3e8b9 2020-01-20 rsc 
22 41b3e8b9 2020-01-20 rsc #define UC_M_PC 40
23 41b3e8b9 2020-01-20 rsc #define UC_M_NPC 48
24 41b3e8b9 2020-01-20 rsc 
25 41b3e8b9 2020-01-20 rsc extern int __getcontext (ucontext_t *ucp);
26 41b3e8b9 2020-01-20 rsc extern int __setcontext (const ucontext_t *ucp, int restoremask);
27 41b3e8b9 2020-01-20 rsc 
28 41b3e8b9 2020-01-20 rsc int
29 41b3e8b9 2020-01-20 rsc swapcontext (ucontext_t *oucp, const ucontext_t *ucp)
30 41b3e8b9 2020-01-20 rsc {
31 41b3e8b9 2020-01-20 rsc   extern void __swapcontext_ret (void);
32 41b3e8b9 2020-01-20 rsc   /* Save the current machine context to oucp.  */
33 41b3e8b9 2020-01-20 rsc   __getcontext (oucp);
34 41b3e8b9 2020-01-20 rsc   /* Modify oucp to skip the __setcontext call on reactivation.  */
35 41b3e8b9 2020-01-20 rsc   *(long*)((char*)oucp+UC_M_PC) = (long)__swapcontext_ret;
36 41b3e8b9 2020-01-20 rsc   *(long*)((char*)oucp+UC_M_NPC) = (long)__swapcontext_ret + 4;
37 41b3e8b9 2020-01-20 rsc   /* Restore the machine context in ucp.  */
38 41b3e8b9 2020-01-20 rsc   __setcontext (ucp, 1);
39 41b3e8b9 2020-01-20 rsc   return 0;
40 41b3e8b9 2020-01-20 rsc }
41 41b3e8b9 2020-01-20 rsc 
42 41b3e8b9 2020-01-20 rsc asm ("							\n\
43 41b3e8b9 2020-01-20 rsc 	.text						\n\
44 41b3e8b9 2020-01-20 rsc 	.type	__swapcontext_ret, #function		\n\
45 41b3e8b9 2020-01-20 rsc __swapcontext_ret:					\n\
46 41b3e8b9 2020-01-20 rsc 	return	%i7 + 8					\n\
47 41b3e8b9 2020-01-20 rsc 	 clr	%o0					\n\
48 41b3e8b9 2020-01-20 rsc 	.size	__swapcontext_ret, .-__swapcontext_ret	\n\
49 41b3e8b9 2020-01-20 rsc      ");