1 /* $NetBSD: quota.c,v 1.4 2014/12/10 04:37:59 christos Exp $ */
2
3 /*
4 * Copyright (C) 2004, 2005, 2007 Internet Systems Consortium, Inc. ("ISC")
5 * Copyright (C) 2000, 2001 Internet Software Consortium.
6 *
7 * Permission to use, copy, modify, and/or distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
9 * copyright notice and this permission notice appear in all copies.
10 *
11 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
12 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
13 * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
14 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
15 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
16 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
17 * PERFORMANCE OF THIS SOFTWARE.
18 */
19
20 /* Id: quota.c,v 1.18 2007/06/19 23:47:17 tbox Exp */
21
22 /*! \file */
23
24 #include <config.h>
25
26 #include <stddef.h>
27
28 #include <isc/quota.h>
29 #include <isc/util.h>
30
31 isc_result_t
isc_quota_init(isc_quota_t * quota,int max)32 isc_quota_init(isc_quota_t *quota, int max) {
33 quota->max = max;
34 quota->used = 0;
35 quota->soft = 0;
36 return (isc_mutex_init("a->lock));
37 }
38
39 void
isc_quota_destroy(isc_quota_t * quota)40 isc_quota_destroy(isc_quota_t *quota) {
41 INSIST(quota->used == 0);
42 quota->max = 0;
43 quota->used = 0;
44 quota->soft = 0;
45 DESTROYLOCK("a->lock);
46 }
47
48 void
isc_quota_soft(isc_quota_t * quota,int soft)49 isc_quota_soft(isc_quota_t *quota, int soft) {
50 LOCK("a->lock);
51 quota->soft = soft;
52 UNLOCK("a->lock);
53 }
54
55 void
isc_quota_max(isc_quota_t * quota,int max)56 isc_quota_max(isc_quota_t *quota, int max) {
57 LOCK("a->lock);
58 quota->max = max;
59 UNLOCK("a->lock);
60 }
61
62 isc_result_t
isc_quota_reserve(isc_quota_t * quota)63 isc_quota_reserve(isc_quota_t *quota) {
64 isc_result_t result;
65 LOCK("a->lock);
66 if (quota->max == 0 || quota->used < quota->max) {
67 if (quota->soft == 0 || quota->used < quota->soft)
68 result = ISC_R_SUCCESS;
69 else
70 result = ISC_R_SOFTQUOTA;
71 quota->used++;
72 } else
73 result = ISC_R_QUOTA;
74 UNLOCK("a->lock);
75 return (result);
76 }
77
78 void
isc_quota_release(isc_quota_t * quota)79 isc_quota_release(isc_quota_t *quota) {
80 LOCK("a->lock);
81 INSIST(quota->used > 0);
82 quota->used--;
83 UNLOCK("a->lock);
84 }
85
86 isc_result_t
isc_quota_attach(isc_quota_t * quota,isc_quota_t ** p)87 isc_quota_attach(isc_quota_t *quota, isc_quota_t **p)
88 {
89 isc_result_t result;
90 INSIST(p != NULL && *p == NULL);
91 result = isc_quota_reserve(quota);
92 if (result == ISC_R_SUCCESS || result == ISC_R_SOFTQUOTA)
93 *p = quota;
94 return (result);
95 }
96
97 void
isc_quota_detach(isc_quota_t ** p)98 isc_quota_detach(isc_quota_t **p)
99 {
100 INSIST(p != NULL && *p != NULL);
101 isc_quota_release(*p);
102 *p = NULL;
103 }
104