common/syscall/sigtimedwait.c

	sigtimedwait.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 2005 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

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

#include <sys/param.h>
#include <sys/types.h>
#include <sys/bitmap.h>
#include <sys/sysmacros.h>
#include <sys/systm.h>
#include <sys/user.h>
#include <sys/errno.h>
#include <sys/proc.h>
#include <sys/fault.h>
#include <sys/procset.h>
#include <sys/signal.h>
#include <sys/siginfo.h>
#include <sys/time.h>
#include <sys/kmem.h>
#include <sys/schedctl.h>
#include <sys/debug.h>
#include <sys/condvar_impl.h>
#include <sys/model.h>
#include <sys/sdt.h>
#include <sys/zone.h>

static int
copyout_siginfo(model_t datamodel, k_siginfo_t *ksip, void *uaddr)
{
    zoneid_t zoneid = getzoneid();

    if (datamodel == DATAMODEL_NATIVE) {
        if (SI_FROMUSER(ksip) && zoneid != GLOBAL_ZONEID &&
            zoneid != ksip->si_zoneid) {
            k_siginfo_t sani_sip = *ksip;
            sani_sip.si_pid = curproc->p_zone->zone_zsched->p_pid;
            sani_sip.si_uid = 0;
            sani_sip.si_ctid = -1;
            sani_sip.si_zoneid = zoneid;
            if (copyout(&sani_sip, uaddr, sizeof (sani_sip)))
                return (set_errno(EFAULT));
        } else {
            if (copyout(ksip, uaddr, sizeof (*ksip)))
                return (set_errno(EFAULT));
        }
    }
#ifdef _SYSCALL32_IMPL
    else {
        siginfo32_t si32;

        siginfo_kto32(ksip, &si32);
        if (SI_FROMUSER(ksip) && zoneid != GLOBAL_ZONEID &&
            zoneid != ksip->si_zoneid) {
            si32.si_pid = curproc->p_zone->zone_zsched->p_pid;
            si32.si_uid = 0;
            si32.si_ctid = -1;
            si32.si_zoneid = zoneid;
        }
        if (copyout(&si32, uaddr, sizeof (si32)))
            return (set_errno(EFAULT));
    }
#endif
    return (ksip->si_signo);
}

/*
 * Wait until a signal within a specified set is posted or until the
 * time interval 'timeout' if specified.  The signal is caught but
 * not delivered. The value of the signal is returned to the caller.
 */
int
sigtimedwait(sigset_t *setp, siginfo_t *siginfop, timespec_t *timeoutp)
{
    sigset_t set;
    k_sigset_t kset;
    k_sigset_t oldmask;
    kthread_t *t = curthread;
    klwp_t *lwp = ttolwp(t);
    proc_t *p = ttoproc(t);
    timespec_t sig_timeout;
    timespec_t *rqtp = NULL;
    int timecheck = 0;
    int ret;
    int error = 0;
    k_siginfo_t info, *infop;
    model_t datamodel = get_udatamodel();

    if (timeoutp) {
        timespec_t now;

        timecheck = timechanged;
        gethrestime(&now);
        if (datamodel == DATAMODEL_NATIVE) {
            if (copyin(timeoutp, &sig_timeout,
                sizeof (sig_timeout)))
                return (set_errno(EFAULT));
        } else {
            timespec32_t timeout32;

            if (copyin(timeoutp, &timeout32, sizeof (timeout32)))
                return (set_errno(EFAULT));
            TIMESPEC32_TO_TIMESPEC(&sig_timeout, &timeout32)
        }

        if (itimerspecfix(&sig_timeout))
            return (set_errno(EINVAL));
        /*
         * Convert the timespec value into absolute time.
         */
        timespecadd(&sig_timeout, &now);
        rqtp = &sig_timeout;
    }
    if (copyin(setp, &set, sizeof (set)))
        return (set_errno(EFAULT));
    sigutok(&set, &kset);
    if (sigisempty(&kset))
        return (set_errno(EINVAL));

    mutex_enter(&p->p_lock);
    /*
     * set the thread's signal mask to unmask
     * those signals in the specified set.
     */
    schedctl_finish_sigblock(t);
    oldmask = t->t_hold;
    sigdiffset(&t->t_hold, &kset);

    /*
     * Wait until we take a signal or until
     * the absolute future time is passed.
     */
    while ((ret = cv_waituntil_sig(&t->t_delay_cv, &p->p_lock,
        rqtp, timecheck)) > 0)
        continue;
    if (ret == -1)
        error = EAGAIN;

    /*
     * Restore thread's signal mask to its previous value.
     */
    t->t_hold = oldmask;
    t->t_sig_check = 1; /* so post_syscall sees new t_hold mask */

    if (error) {
        mutex_exit(&p->p_lock);
        return (set_errno(error));  /* timer expired */
    }
    /*
     * Don't bother with signal if it is not in request set.
     */
    if (lwp->lwp_cursig == 0 || !sigismember(&kset, lwp->lwp_cursig)) {
        mutex_exit(&p->p_lock);
        /*
         * lwp_cursig is zero if pokelwps() awakened cv_wait_sig().
         * This happens if some other thread in this process called
         * forkall() or exit().
         */
        return (set_errno(EINTR));
    }

    if (lwp->lwp_curinfo)
        infop = &lwp->lwp_curinfo->sq_info;
    else {
        infop = &info;
        bzero(infop, sizeof (info));
        infop->si_signo = lwp->lwp_cursig;
        infop->si_code = SI_NOINFO;
    }

    lwp->lwp_ru.nsignals++;
    ret = lwp->lwp_cursig;
    DTRACE_PROC2(signal__clear, int, ret, ksiginfo_t *, infop);
    lwp->lwp_cursig = 0;
    lwp->lwp_extsig = 0;
    mutex_exit(&p->p_lock);

    if (siginfop)
        ret = copyout_siginfo(datamodel, infop, siginfop);
    if (lwp->lwp_curinfo) {
        siginfofree(lwp->lwp_curinfo);
        lwp->lwp_curinfo = NULL;
    }
    return (ret);
}