_lwp.c revision 1.3 
1/*	$NetBSD: _lwp.c,v 1.3 2003/04/07 21:04:21 kleink Exp $	*/
2
3/*
4 * Copyright (c) 2001 Wasabi Systems, Inc.
5 * All rights reserved.
6 *
7 * Written by Allen Briggs for Wasabi Systems, Inc.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. All advertising materials mentioning features or use of this software
18 *    must display the following acknowledgement:
19 *      This product includes software developed for the NetBSD Project by
20 *      Wasabi Systems, Inc.
21 * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22 *    or promote products derived from this software without specific prior
23 *    written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35 * POSSIBILITY OF SUCH DAMAGE.
36 */
37
38#include "namespace.h"
39#include <sys/types.h>
40#include <ucontext.h>
41#include <lwp.h>
42#include <stdlib.h>
43
44void
45_lwp_makecontext(ucontext_t *u, void (*start)(void *), void *arg,
46	void *private, caddr_t stack_base, size_t stack_size)
47{
48	void	**sp;
49
50	getcontext(u);
51	u->uc_link = NULL;
52
53	u->uc_stack.ss_sp = stack_base;
54	u->uc_stack.ss_size = stack_size;
55
56	sp = (void **) (stack_base + stack_size);
57
58	u->uc_mcontext.__gregs[3] = (int) arg;		/* arg1 */
59	u->uc_mcontext.__gregs[1] = ((int) sp) - 12;	/* stack */
60	u->uc_mcontext.__gregs[33] = (int) _lwp_exit;	/* LR */
61	u->uc_mcontext.__gregs[34] = (int) start;	/* PC */
62}
63