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/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (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 2006 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#include <stdlib.h>
#include <stdio.h>
#include "nscd_db.h"
#include "nscd_log.h"
static rwlock_t addrDB_rwlock = DEFAULTRWLOCK;
static nscd_db_t *addrDB = NULL;
/*
* internal structure representing a nscd internal address
*/
typedef struct nscd_int_addr {
int to_delete; /* no longer valid */
int type;
void *ptr;
nscd_seq_num_t seq_num;
rwlock_t rwlock; /* used to serialize get and destroy */
} nscd_int_addr_t;
/*
* FUNCTION: _nscd_create_int_addrDB
*
* Create the internal address database to keep track of the
* memory allocated by _nscd_alloc.
*/
void *
_nscd_create_int_addrDB()
{
nscd_db_t *ret;
char *me = "_nscd_create_int_addrDB";
_NSCD_LOG(NSCD_LOG_INT_ADDR | NSCD_LOG_CONFIG, NSCD_LOG_LEVEL_DEBUG)
(me, "initializing the internal address database\n");
(void) rw_wrlock(&addrDB_rwlock);
if (addrDB != NULL) {
(void) rw_unlock(&addrDB_rwlock);
return (addrDB);
}
ret = _nscd_alloc_db(NSCD_DB_SIZE_LARGE);
if (ret != NULL)
addrDB = ret;
(void) rw_unlock(&addrDB_rwlock);
return (ret);
}
/*
* FUNCTION: _nscd_add_int_addr
*
* Add an address of 'type' to the internal address database.
*/
nscd_rc_t
_nscd_add_int_addr(
void *ptr,
int type,
nscd_seq_num_t seq_num)
{
int size;
char buf[2 * sizeof (ptr) + 1];
nscd_db_entry_t *db_entry;
nscd_int_addr_t *int_addr;
if (ptr == NULL)
return (NSCD_INVALID_ARGUMENT);
(void) snprintf(buf, sizeof (buf), "%p", ptr);
size = sizeof (*int_addr);
db_entry = _nscd_alloc_db_entry(NSCD_DATA_ADDR,
(const char *)buf, size, 1, 1);
if (db_entry == NULL)
return (NSCD_NO_MEMORY);
int_addr = (nscd_int_addr_t *)*(db_entry->data_array);
int_addr->ptr = ptr;
int_addr->type = type;
int_addr->seq_num = seq_num;
(void) rwlock_init(&int_addr->rwlock, USYNC_THREAD, NULL);
(void) rw_wrlock(&addrDB_rwlock);
(void) _nscd_add_db_entry(addrDB, buf, db_entry,
NSCD_ADD_DB_ENTRY_FIRST);
(void) rw_unlock(&addrDB_rwlock);
return (NSCD_SUCCESS);
}
/*
* FUNCTION: _nscd_is_int_addr
*
* Check to see if an address can be found in the internal
* address database, if so, obtain a reader lock on the
* associated rw_lock. The caller needs to unlock it when
* done using the data.
*/
rwlock_t *
_nscd_is_int_addr(
void *ptr,
nscd_seq_num_t seq_num)
{
char *me = "_nscd_is_int_addr";
char ptrstr[1 + 2 * sizeof (ptr)];
rwlock_t *addr_rwlock;
const nscd_db_entry_t *db_entry;
if (ptr == NULL)
return (NULL);
(void) snprintf(ptrstr, sizeof (ptrstr), "%p", ptr);
(void) rw_rdlock(&addrDB_rwlock);
db_entry = _nscd_get_db_entry(addrDB, NSCD_DATA_ADDR,
(const char *)ptrstr, NSCD_GET_FIRST_DB_ENTRY, 0);
if (db_entry != NULL) {
nscd_int_addr_t *int_addr;
int_addr = (nscd_int_addr_t *)*(db_entry->data_array);
addr_rwlock = &int_addr->rwlock;
(void) rw_rdlock(addr_rwlock);
/*
* If the data is marked as to be deleted
* or the sequence number does not match,
* return NULL.
*/
if (int_addr->to_delete == 1 ||
int_addr->seq_num != seq_num) {
(void) rw_unlock(addr_rwlock);
addr_rwlock = NULL;
}
_NSCD_LOG(NSCD_LOG_INT_ADDR, NSCD_LOG_LEVEL_DEBUG)
(me, "found %p, seq# = %lld\n", ptr, int_addr->seq_num);
} else
addr_rwlock = NULL;
(void) rw_unlock(&addrDB_rwlock);
return (addr_rwlock);
}
/*
* FUNCTION: _nscd_del_int_addr
*
* Delete an address from the internal address database.
*/
void
_nscd_del_int_addr(
void *ptr,
nscd_seq_num_t seq_num)
{
char *me = "_nscd_del_int_addr";
char ptrstr[1 + 2 * sizeof (ptr)];
rwlock_t *addr_rwlock;
nscd_int_addr_t *int_addr;
const nscd_db_entry_t *db_entry;
if (ptr == NULL)
return;
_NSCD_LOG(NSCD_LOG_INT_ADDR, NSCD_LOG_LEVEL_DEBUG)
(me, "deleting int addr %p (%d)\n", ptr, seq_num);
(void) snprintf(ptrstr, sizeof (ptrstr), "%p", ptr);
(void) rw_rdlock(&addrDB_rwlock);
/*
* first find the db entry and make sure that
* no one is currently locking it. i.e.,
* no one is waiting to use the same address.
* If it is locked, rw_wrlock() will not return
* until it is unlocked.
*/
db_entry = _nscd_get_db_entry(addrDB,
NSCD_DATA_ADDR,
(const char *)ptrstr,
NSCD_GET_FIRST_DB_ENTRY, 0);
if (db_entry != NULL) {
int_addr = (nscd_int_addr_t *)*(db_entry->data_array);
addr_rwlock = &int_addr->rwlock;
(void) rw_wrlock(addr_rwlock);
} else {
(void) rw_unlock(&addrDB_rwlock);
return;
}
(void) rw_unlock(&addrDB_rwlock);
/*
* delete the db entry if the sequence numbers match
*/
if (int_addr->seq_num == seq_num) {
(void) rw_wrlock(&addrDB_rwlock);
(void) _nscd_delete_db_entry(addrDB,
NSCD_DATA_ADDR,
(const char *)ptrstr,
NSCD_DEL_FIRST_DB_ENTRY, 0);
(void) rw_unlock(&addrDB_rwlock);
}
}
/*
* FUNCTION: _nscd_destroy_int_addrDB
*
* Destroy the internal address database.
*/
void
_nscd_destroy_int_addrDB()
{
(void) rw_wrlock(&addrDB_rwlock);
_nscd_free_db(addrDB);
addrDB = NULL;
(void) rw_unlock(&addrDB_rwlock);
}
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