NetBSD/dist/bind/lib/isc/quota.c

104 lines
2.4 KiB
C

/* $NetBSD: quota.c,v 1.1.1.4 2007/01/27 21:07:47 christos Exp $ */
/*
* Copyright (C) 2004, 2005 Internet Systems Consortium, Inc. ("ISC")
* Copyright (C) 2000, 2001 Internet Software Consortium.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
* REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
* INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
* LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
* OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
* PERFORMANCE OF THIS SOFTWARE.
*/
/* Id: quota.c,v 1.13.18.3 2005/07/27 02:44:21 marka 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;
}