xref: /titanic_41/usr/src/lib/libc/sparcv9/gen/getctxt.c (revision f48205be61a214698b763ff550ab9e657525104c)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 
23 /*	Copyright (c) 1988 AT&T	*/
24 /*	  All Rights Reserved  	*/
25 
26 /*
27  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
28  * Use is subject to license terms.
29  */
30 
31 #pragma ident	"%Z%%M%	%I%	%E% SMI"
32 
33 #pragma weak _private_getcontext = _getcontext
34 #pragma weak getcontext = _getcontext
35 
36 #include "synonyms.h"
37 #include "thr_uberdata.h"
38 #include <ucontext.h>
39 #include <sys/types.h>
40 
41 int
42 getcontext(ucontext_t *ucp)
43 {
44 	greg_t *reg;
45 
46 	ucp->uc_flags = UC_ALL;
47 	if (__getcontext_syscall(ucp))
48 		return (-1);
49 
50 	/*
51 	 * Note that %o1 and %g1 are modified by the system call
52 	 * routine. ABI calling conventions specify that the caller
53 	 * cannot depend upon %o0 through %o5 nor %g1, so no effort is
54 	 * made to maintain these registers. %o0 is forced to reflect
55 	 * an affirmative return code.
56 	 */
57 	reg = ucp->uc_mcontext.gregs;
58 	reg[REG_SP] = getfp();
59 	reg[REG_O7] = caller();
60 	reg[REG_PC] = reg[REG_O7] + 8;
61 	reg[REG_nPC] = reg[REG_PC] + 4;
62 	reg[REG_O0] = 0;
63 
64 	return (0);
65 }
66