common/syscall/sigaltstack.c

/*
 * 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 */


#pragma ident   "%Z%%M% %I% %E% SMI"

#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 */