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/* obj-copy-out.c - Copy out a capability to a client.
Copyright (C) 2004 Free Software Foundation, Inc.
Written by Marcus Brinkmann <marcus@gnu.org>
This file is part of the GNU Hurd.
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this program; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#if HAVE_CONFIG_H
#include <config.h>
#endif
#include <errno.h>
#include <pthread.h>
#include <stdlib.h>
#include "cap-server-intern.h"
/* Copy out a capability for the capability OBJ to the user CLIENT.
Returns the capability ID (valid only for this user) in *R_ID, or
an error. OBJ must be locked. Note: No internal reference for
this capability is allocated for the caller. */
error_t
_hurd_cap_obj_copy_out (hurd_cap_obj_t obj, hurd_cap_bucket_t bucket,
_hurd_cap_client_t client, _hurd_cap_id_t *r_id)
{
void *new_entry;
_hurd_cap_obj_entry_t entry;
pthread_mutex_lock (&client->lock);
entry = (_hurd_cap_obj_entry_t) hurd_ihash_find (&client->caps_reverse,
(hurd_ihash_key_t) obj);
if (entry)
{
entry->external_refs++;
*r_id = entry->id;
pthread_mutex_unlock (&client->lock);
return 0;
}
else
{
_hurd_cap_obj_entry_t entry_check;
error_t err;
pthread_mutex_unlock (&client->lock);
err = hurd_slab_alloc (&_hurd_cap_obj_entry_space, &new_entry);
if (err)
return err;
entry = new_entry;
entry->cap_obj = obj;
/* ID is filled in when adding the object to the table. */
/* CLIENT_ITEM is filled after the object has been entered. */
/* DEAD is 0 for initialized objects. */
/* INTERNAL_REFS is 1 for initialized objects. */
/* EXTERNAL_REFS is 1 for initialized objects. */
pthread_mutex_lock (&client->lock);
entry_check = hurd_ihash_find (&client->caps_reverse,
(hurd_ihash_key_t) obj);
if (entry_check)
{
/* Somebody else was faster. */
entry_check->external_refs++;
*r_id = entry_check->id;
pthread_mutex_unlock (&client->lock);
hurd_slab_dealloc (&_hurd_cap_obj_entry_space, entry);
return 0;
}
/* Add the entry to the cap table of the client. */
err = hurd_table_enter (&client->caps, &entry, &entry->id);
if (err)
{
pthread_mutex_unlock (&client->lock);
hurd_slab_dealloc (&_hurd_cap_obj_entry_space, entry);
return err;
}
err = hurd_ihash_add (&client->caps_reverse,
(hurd_ihash_key_t) obj, entry);
if (err)
{
hurd_table_remove (&client->caps, entry->id);
pthread_mutex_unlock (&client->lock);
hurd_slab_dealloc (&_hurd_cap_obj_entry_space, entry);
return err;
}
*r_id = entry->id;
pthread_mutex_unlock (&client->lock);
/* Add the object to the list. */
_hurd_cap_list_item_add (&obj->clients, &entry->client_item);
/* Add a reference for the internal reference of the capability
entry to the capability object. */
obj->refs++;
/* FIXME: Should probably use spin lock here, or so. */
pthread_mutex_lock (&bucket->lock);
bucket->nr_caps++;
pthread_mutex_unlock (&bucket->lock);
return 0;
}
}
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