NetBSD/sys/compat/mach/mach_task.c

/*	$NetBSD: mach_task.c,v 1.52 2003/12/24 23:22:22 manu Exp $ */

/*-
 * Copyright (c) 2002-2003 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Emmanuel Dreyfus
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *        This product includes software developed by the NetBSD
 *        Foundation, Inc. and its contributors.
 * 4. Neither the name of The NetBSD Foundation nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include "opt_ktrace.h"
#include "opt_compat_darwin.h"

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: mach_task.c,v 1.52 2003/12/24 23:22:22 manu Exp $");

#include <sys/types.h>
#include <sys/param.h>
#include <sys/exec.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/ktrace.h>
#include <sys/resourcevar.h>
#include <sys/malloc.h>
#include <sys/sa.h>
#include <sys/mount.h>
#include <sys/ktrace.h>
#include <sys/syscallargs.h>

#include <uvm/uvm_extern.h>
#include <uvm/uvm_param.h>

#include <compat/mach/mach_types.h>
#include <compat/mach/mach_message.h>
#include <compat/mach/mach_clock.h>
#include <compat/mach/mach_errno.h>
#include <compat/mach/mach_exec.h>
#include <compat/mach/mach_port.h>
#include <compat/mach/mach_task.h>
#include <compat/mach/mach_services.h>
#include <compat/mach/mach_syscallargs.h>

#ifdef COMPAT_DARWIN
#include <compat/darwin/darwin_exec.h>
#endif

#define ISSET(t, f)     ((t) & (f))

static void 
update_exception_port(struct mach_emuldata *, int exc, struct mach_port *);

int 
mach_task_get_special_port(args)
	struct mach_trap_args *args;
{
	mach_task_get_special_port_request_t *req = args->smsg;
	mach_task_get_special_port_reply_t *rep = args->rmsg;
	size_t *msglen = args->rsize;
	struct lwp *l = args->l;
	struct lwp *tl = args->tl;
	struct mach_emuldata *med;
	struct mach_right *mr;

	med = (struct mach_emuldata *)tl->l_proc->p_emuldata;

	switch (req->req_which_port) {
	case MACH_TASK_KERNEL_PORT:
		mr = mach_right_get(med->med_kernel, l, MACH_PORT_TYPE_SEND, 0);
		break;

	case MACH_TASK_HOST_PORT:
		mr = mach_right_get(med->med_host, l, MACH_PORT_TYPE_SEND, 0);
		break;

	case MACH_TASK_BOOTSTRAP_PORT:
		mr = mach_right_get(med->med_bootstrap, 
		    l, MACH_PORT_TYPE_SEND, 0);
		break;

	case MACH_TASK_WIRED_LEDGER_PORT:
	case MACH_TASK_PAGED_LEDGER_PORT:
	default:
		uprintf("mach_task_get_special_port(): unimpl. port %d\n",
		    req->req_which_port);
		return mach_msg_error(args, EINVAL);
		break;
	}

	*msglen = sizeof(*rep);
	mach_set_header(rep, req, *msglen);
	mach_add_port_desc(rep, mr->mr_name);
	mach_set_trailer(rep, *msglen);

	return 0;
}

int 
mach_ports_lookup(args)
	struct mach_trap_args *args;
{
	mach_ports_lookup_request_t *req = args->smsg;
	mach_ports_lookup_reply_t *rep = args->rmsg;
	size_t *msglen = args->rsize;
	struct lwp *l = args->l;
	struct lwp *tl = args->tl;
	struct proc *p = l->l_proc;
	struct mach_emuldata *med;
	struct mach_right *mr;
	mach_port_name_t mnp[7];
	void *uaddr;
	int error;
	int count;

	/* 
	 * This is some out of band data sent with the reply. In the
	 * encountered situation, the out of band data has always been null
	 * filled. We have to see more of this in order to fully understand
	 * how this trap works.
	 */
	med = (struct mach_emuldata *)tl->l_proc->p_emuldata;
	mnp[0] = (mach_port_name_t)MACH_PORT_DEAD;
	mnp[3] = (mach_port_name_t)MACH_PORT_DEAD;
	mnp[5] = (mach_port_name_t)MACH_PORT_DEAD;
	mnp[6] = (mach_port_name_t)MACH_PORT_DEAD;

	mr = mach_right_get(med->med_kernel, l, MACH_PORT_TYPE_SEND, 0);
	mnp[MACH_TASK_KERNEL_PORT] = mr->mr_name;
	mr = mach_right_get(med->med_host, l, MACH_PORT_TYPE_SEND, 0);
	mnp[MACH_TASK_HOST_PORT] = mr->mr_name;
	mr = mach_right_get(med->med_bootstrap, l, MACH_PORT_TYPE_SEND, 0);
	mnp[MACH_TASK_BOOTSTRAP_PORT] = mr->mr_name;

	/*
	 * On Darwin, the data seems always null...
	 */
	uaddr = NULL;
	if ((error = mach_ool_copyout(p, &mnp[0], 
	    &uaddr, sizeof(mnp), MACH_OOL_TRACE)) != 0)
		return mach_msg_error(args, error);

	count = 3; /* XXX Shouldn't this be 7? */

	*msglen = sizeof(*rep);
	mach_set_header(rep, req, *msglen);
	mach_add_ool_ports_desc(rep, uaddr, count);

	rep->rep_init_port_set_count = count;

	mach_set_trailer(rep, *msglen);

	return 0;
}

int 
mach_task_set_special_port(args)
	struct mach_trap_args *args;
{
	mach_task_set_special_port_request_t *req = args->smsg;
	mach_task_set_special_port_reply_t *rep = args->rmsg;
	size_t *msglen = args->rsize;
	struct lwp *l = args->l;
	struct lwp *tl = args->tl;
	mach_port_t mn;
	struct mach_right *mr;
	struct mach_port *mp;
	struct mach_emuldata *med;

	mn = req->req_special_port.name;

	/* Null port ? */
	if (mn == 0)
		return mach_msg_error(args, 0);

	/* Does the inserted port exists? */
	if ((mr = mach_right_check(mn, l, MACH_PORT_TYPE_ALL_RIGHTS)) == 0)
		return mach_msg_error(args, EPERM);

	if (mr->mr_type == MACH_PORT_TYPE_DEAD_NAME)
		return mach_msg_error(args, EINVAL);

	med = (struct mach_emuldata *)tl->l_proc->p_emuldata;

	switch (req->req_which_port) {
	case MACH_TASK_KERNEL_PORT:
		mp = med->med_kernel;
		med->med_kernel = mr->mr_port;
		mp->mp_refcount--;
		if (mp->mp_refcount == 0)
			mach_port_put(mp);
		break;

	case MACH_TASK_HOST_PORT:
		mp = med->med_host;
		med->med_host = mr->mr_port;
		mp->mp_refcount--;
		if (mp->mp_refcount == 0)
			mach_port_put(mp);
		break;

	case MACH_TASK_BOOTSTRAP_PORT:
		mp = med->med_bootstrap;
		med->med_bootstrap = mr->mr_port;
		mp->mp_refcount--;
		if (mp->mp_refcount == 0)
			mach_port_put(mp);
#ifdef COMPAT_DARWIN
		/*
		 * mach_init sets the bootstrap port for any new process.
		 */
		{
			struct darwin_emuldata *ded;

			ded = tl->l_proc->p_emuldata;
			if (ded->ded_fakepid == 1) {
				mach_bootstrap_port = med->med_bootstrap;
#ifdef DEBUG_DARWIN
				printf("*** New bootstrap port %p, "
				    "recv %p [%p]\n",
				    mach_bootstrap_port, 
				    mach_bootstrap_port->mp_recv,
				    mach_bootstrap_port->mp_recv->mr_sethead);
#endif /* DEBUG_DARWIN */
			}
		}
#endif /* COMPAT_DARWIN */
		break;

	default:
		uprintf("mach_task_set_special_port: unimplemented port %d\n",
		    req->req_which_port);
	}

	*msglen = sizeof(*rep);
	mach_set_header(rep, req, *msglen);

	rep->rep_retval = 0;

	mach_set_trailer(rep, *msglen);

	return 0;
}

int
mach_task_threads(args)
	struct mach_trap_args *args;
{
	mach_task_threads_request_t *req = args->smsg;
	mach_task_threads_reply_t *rep = args->rmsg;
	size_t *msglen = args->rsize;
	struct lwp *l = args->l;
	struct lwp *tl = args->tl;
	struct proc *tp = tl->l_proc;
	struct lwp *cl;
	struct mach_emuldata *med;
	struct mach_lwp_emuldata *mle;
	int error;
	void *uaddr;
	size_t size;
	int i = 0;
	struct mach_right *mr;
	mach_port_name_t *mnp;

	med = tp->p_emuldata;
	size = tp->p_nlwps * sizeof(*mnp);
	mnp = malloc(size, M_TEMP, M_WAITOK);
	uaddr = NULL;

	LIST_FOREACH(cl, &tp->p_lwps, l_sibling) {
		mle = cl->l_emuldata;
		mr = mach_right_get(mle->mle_kernel, l, MACH_PORT_TYPE_SEND, 0);
		mnp[i++] = mr->mr_name;
	}

	/* This will free mnp */
	if ((error = mach_ool_copyout(l->l_proc, mnp, &uaddr, 
	    size, MACH_OOL_TRACE|MACH_OOL_FREE)) != 0)
		return mach_msg_error(args, error);

	*msglen = sizeof(*rep);
	mach_set_header(rep, req, *msglen);
	mach_add_ool_ports_desc(rep, uaddr, tp->p_nlwps);

	rep->rep_count = tp->p_nlwps;

	mach_set_trailer(rep, *msglen);

	return 0;
}

int
mach_task_get_exception_ports(args)
	struct mach_trap_args *args;
{
	mach_task_get_exception_ports_request_t *req = args->smsg;
	mach_task_get_exception_ports_reply_t *rep = args->rmsg;
	struct lwp *l = args->l;
	struct lwp *tl = args->tl;
	size_t *msglen = args->rsize;
	struct mach_emuldata *med;
	struct mach_right *mr;
	struct mach_exc_info *mei;
	int i, j, count;

	med = tl->l_proc->p_emuldata;

	/* It always returns an array of 32 ports even if only 9 can be used */
	count = sizeof(rep->rep_old_handler) / sizeof(rep->rep_old_handler[0]);

	mach_set_header(rep, req, *msglen);

	rep->rep_masks_count = count;

	j = 0;
	for (i = 0; i <= MACH_EXC_MAX; i++) {
		if (med->med_exc[i] == NULL)
			continue;

		if (med->med_exc[i]->mp_datatype != MACH_MP_EXC_INFO) {
#ifdef DIAGNOSTIC
			printf("Exception port without mach_exc_info\n");
#endif
			continue;
		}
		mei = med->med_exc[i]->mp_data;

		mr = mach_right_get(med->med_exc[i], l, MACH_PORT_TYPE_SEND, 0);

		mach_add_port_desc(rep, mr->mr_name);

		rep->rep_masks[j] = 1 << i;
		rep->rep_old_behaviors[j] = mei->mei_behavior;
		rep->rep_old_flavors[j] = mei->mei_flavor;

		j++;
	}

	*msglen = sizeof(*rep);
	mach_set_trailer(rep, *msglen);

	return 0;
}

static void 
update_exception_port(med, exc, mp)
	struct mach_emuldata *med;
	int exc;
	struct mach_port *mp;
{
	if (med->med_exc[exc] != NULL) {
		med->med_exc[exc]->mp_refcount--;
		if (med->med_exc[exc]->mp_refcount <= 0)
			mach_port_put(med->med_exc[exc]);
	}
	med->med_exc[exc] = mp;
	mp->mp_refcount++;

	return;
}

int
mach_task_set_exception_ports(args)
	struct mach_trap_args *args;
{
	mach_task_set_exception_ports_request_t *req = args->smsg;
	mach_task_set_exception_ports_reply_t *rep = args->rmsg;
	struct lwp *l = args->l;
	struct lwp *tl = args->tl;
	size_t *msglen = args->rsize;
	struct mach_emuldata *med;
	mach_port_name_t mn;
	struct mach_right *mr;
	struct mach_port *mp;
	struct mach_exc_info *mei;

	mn = req->req_new_port.name;
	if ((mr = mach_right_check(mn, l, MACH_PORT_TYPE_SEND)) == 0)
		return mach_msg_error(args, EPERM);

	mp = mr->mr_port;
#ifdef DIAGNOSTIC
	if ((mp->mp_datatype != MACH_MP_EXC_INFO) && 
	    (mp->mp_datatype != MACH_MP_NONE))
		printf("mach_task_set_exception_ports: data exists\n");
#endif
	mei = malloc(sizeof(*mei), M_EMULDATA, M_WAITOK);
	mei->mei_flavor = req->req_flavor;
	mei->mei_behavior = req->req_behavior;

	mp->mp_data = mei;
	mp->mp_flags |= MACH_MP_DATA_ALLOCATED;
	mp->mp_datatype = MACH_MP_EXC_INFO;

	med = tl->l_proc->p_emuldata;
	if (req->req_mask & MACH_EXC_MASK_BAD_ACCESS)
		update_exception_port(med, MACH_EXC_BAD_ACCESS, mp);
	if (req->req_mask & MACH_EXC_MASK_BAD_INSTRUCTION)
		update_exception_port(med, MACH_EXC_BAD_INSTRUCTION, mp);
	if (req->req_mask & MACH_EXC_MASK_ARITHMETIC) 
		update_exception_port(med, MACH_EXC_ARITHMETIC, mp);
	if (req->req_mask & MACH_EXC_MASK_EMULATION)
		update_exception_port(med, MACH_EXC_EMULATION, mp);
	if (req->req_mask & MACH_EXC_MASK_SOFTWARE)
		update_exception_port(med, MACH_EXC_SOFTWARE, mp);
	if (req->req_mask & MACH_EXC_MASK_BREAKPOINT)
		update_exception_port(med, MACH_EXC_BREAKPOINT, mp);
	if (req->req_mask & MACH_EXC_MASK_SYSCALL)
		update_exception_port(med, MACH_EXC_SYSCALL, mp);
	if (req->req_mask & MACH_EXC_MASK_MACH_SYSCALL)
		update_exception_port(med, MACH_EXC_MACH_SYSCALL, mp);
	if (req->req_mask & MACH_EXC_MASK_RPC_ALERT)
		update_exception_port(med, MACH_EXC_RPC_ALERT, mp);

#ifdef DEBUG_MACH
	if (req->req_mask & (MACH_EXC_ARITHMETIC | 
	    MACH_EXC_EMULATION | MACH_EXC_MASK_SYSCALL | 
	    MACH_EXC_MASK_MACH_SYSCALL | MACH_EXC_RPC_ALERT)) 
		printf("mach_set_exception_ports: some exceptions are "
		    "not supported (mask %x)\n", req->req_mask);
#endif

	*msglen = sizeof(*rep);
	mach_set_header(rep, req, *msglen);

	rep->rep_retval = 0;

	mach_set_trailer(rep, *msglen);

	return 0;
}

int
mach_task_info(args)
	struct mach_trap_args *args;
{
	mach_task_info_request_t *req = args->smsg;
	mach_task_info_reply_t *rep = args->rmsg;
	struct lwp *tl = args->tl;
	size_t *msglen = args->rsize;
	int count;
	struct proc *tp = tl->l_proc;

	switch(req->req_flavor) {
	case MACH_TASK_BASIC_INFO: {	
		struct mach_task_basic_info *mtbi;
		struct rusage *ru;

		count = sizeof(*mtbi) / sizeof(rep->rep_info[0]);
		if (req->req_count < count)
			return mach_msg_error(args, ENOBUFS);

		ru = &tp->p_stats->p_ru;
		mtbi = (struct mach_task_basic_info *)&rep->rep_info[0];

		mtbi->mtbi_suspend_count = ru->ru_nvcsw + ru->ru_nivcsw;
		mtbi->mtbi_virtual_size = ru->ru_ixrss;
		mtbi->mtbi_resident_size = ru->ru_maxrss;
		mtbi->mtbi_user_time.seconds = ru->ru_utime.tv_sec;
		mtbi->mtbi_user_time.microseconds = ru->ru_utime.tv_usec;
		mtbi->mtbi_system_time.seconds = ru->ru_stime.tv_sec;
		mtbi->mtbi_system_time.microseconds = ru->ru_stime.tv_usec;
		mtbi->mtbi_policy = 0;

		*msglen = sizeof(*rep) - sizeof(rep->rep_info) + sizeof(*mtbi);
		break;
	}

	/* XXX this is supposed to be about threads, not processes... */
	case MACH_TASK_THREAD_TIMES_INFO: {
		struct mach_task_thread_times_info *mttti;
		struct rusage *ru;

		count = sizeof(*mttti) / sizeof(rep->rep_info[0]);
		if (req->req_count < count)
			return mach_msg_error(args, ENOBUFS);

		ru = &tp->p_stats->p_ru;
		mttti = (struct mach_task_thread_times_info *)&rep->rep_info[0];

		mttti->mttti_user_time.seconds = ru->ru_utime.tv_sec;
		mttti->mttti_user_time.microseconds = ru->ru_utime.tv_usec;
		mttti->mttti_system_time.seconds = ru->ru_stime.tv_sec;
		mttti->mttti_system_time.microseconds = ru->ru_stime.tv_usec;

		*msglen = sizeof(*rep) - sizeof(rep->rep_info) + sizeof(*mttti);
		break;
	}

	/* XXX a few statistics missing here */
	case MACH_TASK_EVENTS_INFO: {
		struct mach_task_events_info *mtei;
		struct rusage *ru;

		count = sizeof(*mtei) / sizeof(rep->rep_info[0]);
		if (req->req_count < count)
			return mach_msg_error(args, ENOBUFS);

		mtei = (struct mach_task_events_info *)&rep->rep_info[0];
		ru = &tp->p_stats->p_ru;

		mtei->mtei_faults = ru->ru_majflt;
		mtei->mtei_pageins = ru->ru_minflt;
		mtei->mtei_cow_faults = 0; /* XXX */
		mtei->mtei_message_sent = ru->ru_msgsnd;
		mtei->mtei_message_received = ru->ru_msgrcv;
		mtei->mtei_syscalls_mach = 0; /* XXX */
		mtei->mtei_syscalls_unix = 0; /* XXX */
		mtei->mtei_csw = 0; /* XXX */

		*msglen = sizeof(*rep) - sizeof(rep->rep_info) + sizeof(*mtei);
		break;
	}

	default:
		uprintf("mach_task_info: unsupported flavor %d\n", 
		    req->req_flavor);
		return mach_msg_error(args, EINVAL);
	};
	
	mach_set_header(rep, req, *msglen);

	rep->rep_count = count;

	mach_set_trailer(rep, *msglen);
 
	return 0;
}

int
mach_task_suspend(args)
	struct mach_trap_args *args;
{
	mach_task_suspend_request_t *req = args->smsg;
	mach_task_suspend_reply_t *rep = args->rmsg;
	size_t *msglen = args->rsize;
	struct lwp *tl = args->tl;
	struct lwp *lp;
	struct mach_emuldata *med;
	struct proc *tp = tl->l_proc;
	
	med = tp->p_emuldata;
	med->med_suspend++; /* XXX Mach also has a per thread semaphore */
		
	LIST_FOREACH(lp, &tp->p_lwps, l_sibling) {
		switch(lp->l_stat) {
		case LSONPROC:
		case LSRUN:
		case LSSLEEP:
		case LSSUSPENDED:
		case LSZOMB:
		case LSDEAD:
			break;
		default:
			return mach_msg_error(args, 0);	
			break;
		}
	}
	proc_stop(tp, 0);

	*msglen = sizeof(*rep);
	mach_set_header(rep, req, *msglen);

	rep->rep_retval = 0;

	mach_set_trailer(rep, *msglen);

	return 0;
}

int
mach_task_resume(args)
	struct mach_trap_args *args;
{
	mach_task_resume_request_t *req = args->smsg;
	mach_task_resume_reply_t *rep = args->rmsg;
	size_t *msglen = args->rsize;
	struct lwp *tl = args->tl;
	struct mach_emuldata *med;
	struct proc *tp = tl->l_proc;

	med = tp->p_emuldata;
	med->med_suspend--; /* XXX Mach also has a per thread semaphore */
#if 0
	if (med->med_suspend > 0)
		return mach_msg_error(args, 0); /* XXX error code */
#endif
		
	/* XXX We should also wake up the stopped thread... */
#ifdef DEBUG_MACH
	printf("resuming pid %d\n", tp->p_pid);
#endif
	(void)proc_unstop(tp);

	*msglen = sizeof(*rep);
	mach_set_header(rep, req, *msglen);

	rep->rep_retval = 0;

	mach_set_trailer(rep, *msglen);

	return 0;
}

int
mach_task_terminate(args)
	struct mach_trap_args *args;
{
	mach_task_resume_request_t *req = args->smsg;
	mach_task_resume_reply_t *rep = args->rmsg;
	size_t *msglen = args->rsize;
	struct lwp *tl = args->tl;
	struct sys_exit_args cup;
	register_t retval;
	int error;


	SCARG(&cup, rval) = 0;
	error = sys_exit(tl, &cup, &retval);

	*msglen = sizeof(*rep);
	mach_set_header(rep, req, *msglen);

	rep->rep_retval = native_to_mach_errno[error];

	mach_set_trailer(rep, *msglen);

	return 0;
}

int
mach_sys_task_for_pid(l, v, retval)
	struct lwp *l;
	void *v;
	register_t *retval;
{
	struct mach_sys_task_for_pid_args /* {
		syscallarg(mach_port_t) target_tport;
		syscallarg(int) pid;
		syscallarg(mach_port_t) *t;
	} */ *uap = v;
	struct mach_right *mr;
	struct mach_emuldata *med;
	struct proc *p = l->l_proc;
	struct proc *t;
	int error;

	/* 
	 * target_tport is used because the task may be on
	 * a different host. (target_tport, pid) is unique.
	 * We don't support multiple-host configuration
	 * yet, so this parameter should be useless.
	 * However, we still validate it.
	 */
	if ((mr = mach_right_check(SCARG(uap, target_tport), 
	    l, MACH_PORT_TYPE_ALL_RIGHTS)) == NULL)
		return EPERM;

	if ((t = pfind(SCARG(uap, pid))) == NULL)
		return ESRCH;
	
	/* Allowed only if the UID match, if setuid, or if superuser */
	if ((t->p_cred->p_ruid != p->p_cred->p_ruid ||  
		ISSET(t->p_flag, P_SUGID)) &&
		    (error = suser(p->p_ucred, &p->p_acflag)) != 0)
			    return (error);

	/* This will only work on a Mach process */
	if ((t->p_emul != &emul_mach) &&
#ifdef COMPAT_DARWIN
	    (t->p_emul != &emul_darwin) &&
#endif
	    1)
		return EINVAL;

	med = t->p_emuldata;

	if ((mr = mach_right_get(med->med_kernel, l, 
	    MACH_PORT_TYPE_SEND, 0)) == NULL)
		return EINVAL;

	if ((error = copyout(&mr->mr_name, SCARG(uap, t), 
	    sizeof(mr->mr_name))) != 0)
		return error;

	return 0;
}