quota.c 1.83 KB
Newer Older
1
/*
2
 * Copyright (C) 2000, 2001, 2004, 2005, 2007, 2016  Internet Systems Consortium, Inc. ("ISC")
3
 *
4 5 6
 * 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/.
7
 */
8

Automatic Updater's avatar
Automatic Updater committed
9
/* $Id: quota.c,v 1.18 2007/06/19 23:47:17 tbox Exp $ */
10 11

/*! \file */
David Lawrence's avatar
David Lawrence committed
12

13
#include <config.h>
14

Brian Wellington's avatar
Brian Wellington committed
15 16
#include <stddef.h>

17 18 19 20 21 22 23
#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;
24
	quota->soft = 0;
25 26 27 28 29
	return (isc_mutex_init(&quota->lock));
}

void
isc_quota_destroy(isc_quota_t *quota) {
30
	INSIST(quota->used == 0);
31 32 33
	quota->max = 0;
	quota->used = 0;
	quota->soft = 0;
34
	DESTROYLOCK(&quota->lock);
35 36
}

37
void
38 39
isc_quota_soft(isc_quota_t *quota, int soft) {
	LOCK(&quota->lock);
40
	quota->soft = soft;
41 42 43 44 45 46 47 48
	UNLOCK(&quota->lock);
}

void
isc_quota_max(isc_quota_t *quota, int max) {
	LOCK(&quota->lock);
	quota->max = max;
	UNLOCK(&quota->lock);
49 50
}

51 52 53 54
isc_result_t
isc_quota_reserve(isc_quota_t *quota) {
	isc_result_t result;
	LOCK(&quota->lock);
55 56 57 58
	if (quota->max == 0 || quota->used < quota->max) {
		if (quota->soft == 0 || quota->used < quota->soft)
			result = ISC_R_SUCCESS;
		else
59
			result = ISC_R_SOFTQUOTA;
60 61 62
		quota->used++;
	} else
		result = ISC_R_QUOTA;
63 64 65 66 67 68 69 70 71
	UNLOCK(&quota->lock);
	return (result);
}

void
isc_quota_release(isc_quota_t *quota) {
	LOCK(&quota->lock);
	INSIST(quota->used > 0);
	quota->used--;
72
	UNLOCK(&quota->lock);
73 74
}

75 76 77 78 79 80
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);
81 82 83
	if (result == ISC_R_SUCCESS || result == ISC_R_SOFTQUOTA)
		*p = quota;
	return (result);
84
}
85

86 87 88 89 90 91 92
void
isc_quota_detach(isc_quota_t **p)
{
	INSIST(p != NULL && *p != NULL);
	isc_quota_release(*p);
	*p = NULL;
}