swapctxt.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/* Copyright (c) 1988 AT&T */
/* All Rights Reserved */
/*
* Copyright 1996-2003 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#pragma weak swapcontext = _swapcontext
#include "synonyms.h"
#include <ucontext.h>
#include <sys/types.h>
#include "libc.h"
int
swapcontext(ucontext_t *oucp, const ucontext_t *nucp)
{
greg_t *reg;
if (__getcontext_syscall(oucp))
return (-1);
/*
* Note that %o1 and %g1 are modified by the system call
* routine. ABI calling conventions specify that the caller
* can not depend upon %o0 thru %o5 nor g1, so no effort is
* made to maintain these registers. %o0 is forced to reflect
* an affirmative return code.
*/
reg = oucp->uc_mcontext.gregs;
reg[REG_SP] = getfp();
reg[REG_O7] = caller();
reg[REG_PC] = reg[REG_O7] + 8;
reg[REG_nPC] = reg[REG_PC] + 4;
reg[REG_O0] = 0;
return (setcontext((ucontext_t *)nucp));
}