/*
 * 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 2004 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */

#include <sys/param.h>
#include <sys/types.h>
#include <sys/sysmacros.h>
#include <sys/systm.h>
#include <sys/errno.h>
#include <sys/proc.h>
#include <sys/fault.h>
#include <sys/signal.h>
#include <sys/siginfo.h>
#include <sys/debug.h>

int
sigaltstack(struct sigaltstack *ssp, struct sigaltstack *oss)
{
        klwp_t *lwp = ttolwp(curthread);
        struct sigaltstack ss;

        /*
         * User's oss and ss might be the same address, so copyin first and
         * save before copying out.
         */
        if (ssp) {
                if (lwp->lwp_sigaltstack.ss_flags & SS_ONSTACK)
                        return (set_errno(EPERM));
                if (copyin(ssp, &ss, sizeof (ss)))
                        return (set_errno(EFAULT));
                if (ss.ss_flags & ~SS_DISABLE)
                        return (set_errno(EINVAL));
                if (!(ss.ss_flags & SS_DISABLE) && ss.ss_size < MINSIGSTKSZ)
                        return (set_errno(ENOMEM));
        }

        if (oss) {
                if (copyout(&lwp->lwp_sigaltstack,
                    oss, sizeof (struct sigaltstack)))
                        return (set_errno(EFAULT));
        }

        if (ssp)
                lwp->lwp_sigaltstack = ss;

        return (0);
}

#ifdef _LP64
int
sigaltstack32(struct sigaltstack32 *ssp, struct sigaltstack32 *oss)
{
        klwp_t *lwp = ttolwp(curthread);
        struct sigaltstack   *ss;
        struct sigaltstack32 ss32, oss32;

        /*
         * User's oss and ss might be the same address, so copyin first and
         * save before copying out.
         */
        if (ssp) {
                if (lwp->lwp_sigaltstack.ss_flags & SS_ONSTACK)
                        return (set_errno(EPERM));
                if (copyin(ssp, &ss32, sizeof (ss32)))
                        return (set_errno(EFAULT));
                if (ss32.ss_flags & ~SS_DISABLE)
                        return (set_errno(EINVAL));
                if (!(ss32.ss_flags & SS_DISABLE) && ss32.ss_size < MINSIGSTKSZ)
                        return (set_errno(ENOMEM));
        }

        if (oss) {
                /*
                 * copy to ILP32 struct before copyout.
                 */
                ss = &lwp->lwp_sigaltstack;
                oss32.ss_sp    = (caddr32_t)(uintptr_t)ss->ss_sp;
                oss32.ss_size  = (size32_t)ss->ss_size;
                oss32.ss_flags = ss->ss_flags;

                if (copyout(&oss32, oss, sizeof (oss32)))
                        return (set_errno(EFAULT));
        }

        if (ssp) {
                ss = &lwp->lwp_sigaltstack;
                ss->ss_sp = (void *)(uintptr_t)ss32.ss_sp;
                ss->ss_size = (size_t)ss32.ss_size;
                ss->ss_flags = ss32.ss_flags;
        }

        return (0);
}
#endif /* _LP64 */