quota.c revision 0c27b3fe77ac1d5094ba3521e8142d9e7973133f
/*
* Copyright (C) 2000, 2001, 2004, 2005, 2007, 2016 Internet Systems Consortium, Inc. ("ISC")
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*/
/* $Id: quota.c,v 1.18 2007/06/19 23:47:17 tbox Exp $ */
/*! \file */
#include <config.h>
#include <stddef.h>
#include <isc/quota.h>
#include <isc/util.h>
isc_result_t
isc_quota_init(isc_quota_t *quota, int max) {
quota->max = max;
quota->used = 0;
quota->soft = 0;
return (isc_mutex_init(&quota->lock));
}
void
isc_quota_destroy(isc_quota_t *quota) {
INSIST(quota->used == 0);
quota->max = 0;
quota->used = 0;
quota->soft = 0;
DESTROYLOCK(&quota->lock);
}
void
isc_quota_soft(isc_quota_t *quota, int soft) {
LOCK(&quota->lock);
quota->soft = soft;
UNLOCK(&quota->lock);
}
void
isc_quota_max(isc_quota_t *quota, int max) {
LOCK(&quota->lock);
quota->max = max;
UNLOCK(&quota->lock);
}
isc_result_t
isc_quota_reserve(isc_quota_t *quota) {
isc_result_t result;
LOCK(&quota->lock);
if (quota->max == 0 || quota->used < quota->max) {
if (quota->soft == 0 || quota->used < quota->soft)
result = ISC_R_SUCCESS;
else
result = ISC_R_SOFTQUOTA;
quota->used++;
} else
result = ISC_R_QUOTA;
UNLOCK(&quota->lock);
return (result);
}
void
isc_quota_release(isc_quota_t *quota) {
LOCK(&quota->lock);
INSIST(quota->used > 0);
quota->used--;
UNLOCK(&quota->lock);
}
isc_result_t
isc_quota_attach(isc_quota_t *quota, isc_quota_t **p)
{
isc_result_t result;
INSIST(p != NULL && *p == NULL);
result = isc_quota_reserve(quota);
if (result == ISC_R_SUCCESS || result == ISC_R_SOFTQUOTA)
*p = quota;
return (result);
}
void
isc_quota_detach(isc_quota_t **p)
{
INSIST(p != NULL && *p != NULL);
isc_quota_release(*p);
*p = NULL;
}