/*
 * Digest Authentication Module
 * nonce id and pool management (stuff common to nonce-count and one
 * time nonces)
 *
 * Copyright (C) 2008 iptelorg GmbH
 *
 * This file is part of Kamailio, a free SIP server.
 *
 * Kamailio is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version
 *
 * Kamailio 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */

/*
 * Defines:
 *  USE_NC, USE_OT_NONCE  - if neither of them defined no code will be
 *                          compiled
 */

unsigned int nid_pool_no; /* number of index pools, 2^k */

#if defined USE_NC || defined USE_OT_NONCE

#include "nid.h"
#include "../../core/dprint.h"
#include "../../core/bit_scan.h"

struct pool_index *nid_crt = 0;


/* instead of storing only the 2^k size we store also k
 * for faster operations */
unsigned int nid_pool_k;	/* pools no in bits (k in 2^k) */
unsigned int nid_pool_mask; /* mask for computing the current pool*/


/* returns -1 on error, 0 on success */
int init_nonce_id()
{
	unsigned pool_no, r;

	if(nid_crt != 0)
		return 0; /* already init */
	if(nid_pool_no == 0) {
		nid_pool_no = DEFAULT_NID_POOL_SIZE;
	}
	if(nid_pool_no > MAX_NID_POOL_SIZE) {
		LM_WARN("nid_pool_no too big, truncating to %d\n", MAX_NID_POOL_SIZE);
		nid_pool_no = MAX_NID_POOL_SIZE;
	}
	nid_pool_k = bit_scan_reverse32(nid_pool_no);
	nid_pool_mask = (1 << nid_pool_k) - 1;
	pool_no = 1UL << nid_pool_k; /* ROUNDDOWN to 2^k */
	if(pool_no != nid_pool_no) {
		LM_INFO("nid_pool_no rounded down to %d\n", pool_no);
	}
	nid_pool_no = pool_no;

	nid_crt = shm_malloc(sizeof(*nid_crt) * nid_pool_no);
	if(nid_crt == 0) {
		LM_ERR("init_nonce_id: memory allocation failure\n");
		return -1;
	}
	/*  init nc_crt_id with random values */
	for(r = 0; r < nid_pool_no; r++)
		atomic_set(&nid_crt[r].id, random());
	return 0;
}


void destroy_nonce_id()
{
	if(nid_crt) {
		shm_free(nid_crt);
		nid_crt = 0;
	}
}

#endif /*if  defined USE_NC || defined USE_OT_NONCE */
