1/*
2 * (C) 2006-2009 by Pablo Neira Ayuso <pablo@netfilter.org>
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
17 */
18
19#include "queue.h"
20#include "event.h"
21
22#include <errno.h>
23#include <stdio.h>
24#include <stdlib.h>
25#include <string.h>
26#include <sys/socket.h>
27
28static LIST_HEAD(queue_list);	/* list of existing queues */
29static uint32_t qobjects_num;	/* number of active queue objects */
30
31struct queue *
32queue_create(const char *name, int max_objects, unsigned int flags)
33{
34	struct queue *b;
35
36	b = calloc(sizeof(struct queue), 1);
37	if (b == NULL)
38		return NULL;
39
40	b->max_elems = max_objects;
41	INIT_LIST_HEAD(&b->head);
42	b->flags = flags;
43
44	if (flags & QUEUE_F_EVFD) {
45		b->evfd = create_evfd();
46		if (b->evfd == NULL) {
47			free(b);
48			return NULL;
49		}
50	}
51	strncpy(b->name, name, QUEUE_NAMELEN);
52	b->name[QUEUE_NAMELEN-1]='\0';
53	list_add(&b->list, &queue_list);
54
55	return b;
56}
57
58void queue_destroy(struct queue *b)
59{
60	list_del(&b->list);
61	if (b->flags & QUEUE_F_EVFD)
62		destroy_evfd(b->evfd);
63	free(b);
64}
65
66void queue_stats_show(int fd)
67{
68	struct queue *this;
69	int size = 0;
70	char buf[512];
71
72	size += snprintf(buf+size, sizeof(buf),
73			 "allocated queue nodes:\t\t%12u\n\n",
74			 qobjects_num);
75
76	list_for_each_entry(this, &queue_list, list) {
77		size += snprintf(buf+size, sizeof(buf),
78				 "queue %s:\n"
79				 "current elements:\t\t%12u\n"
80				 "maximum elements:\t\t%12u\n"
81				 "not enough space errors:\t%12u\n\n",
82				 this->name,
83				 this->num_elems,
84				 this->max_elems,
85				 this->enospc_err);
86	}
87	send(fd, buf, size, 0);
88}
89
90void queue_node_init(struct queue_node *n, int type)
91{
92	INIT_LIST_HEAD(&n->head);
93	n->type = type;
94}
95
96void *queue_node_data(struct queue_node *n)
97{
98	return ((char *)n) + sizeof(struct queue_node);
99}
100
101struct queue_object *queue_object_new(int type, size_t size)
102{
103	struct queue_object *obj;
104
105	obj = calloc(sizeof(struct queue_object) + size, 1);
106	if (obj == NULL)
107		return NULL;
108
109	obj->qnode.size = size;
110	queue_node_init(&obj->qnode, type);
111	qobjects_num++;
112
113	return obj;
114}
115
116void queue_object_free(struct queue_object *obj)
117{
118	free(obj);
119	qobjects_num--;
120}
121
122int queue_add(struct queue *b, struct queue_node *n)
123{
124	if (!list_empty(&n->head))
125		return 0;
126
127	if (b->num_elems >= b->max_elems) {
128		b->enospc_err++;
129		errno = ENOSPC;
130		return -1;
131	}
132	n->owner = b;
133	list_add_tail(&n->head, &b->head);
134	b->num_elems++;
135	if (b->evfd)
136		write_evfd(b->evfd);
137	return 1;
138}
139
140int queue_del(struct queue_node *n)
141{
142	if (list_empty(&n->head))
143		return 0;
144
145	list_del_init(&n->head);
146	n->owner->num_elems--;
147	if (n->owner->evfd)
148		read_evfd(n->owner->evfd);
149	n->owner = NULL;
150	return 1;
151}
152
153struct queue_node *queue_del_head(struct queue *b)
154{
155	struct queue_node *n = (struct queue_node *) b->head.next;
156	queue_del(n);
157	return n;
158}
159
160int queue_in(struct queue *b, struct queue_node *n)
161{
162	return b == n->owner;
163}
164
165int queue_get_eventfd(struct queue *b)
166{
167	return get_read_evfd(b->evfd);
168}
169
170void queue_iterate(struct queue *b,
171		   const void *data,
172		   int (*iterate)(struct queue_node *n, const void *data2))
173{
174	struct list_head *i, *tmp;
175	struct queue_node *n;
176
177	list_for_each_safe(i, tmp, &b->head) {
178		n = (struct queue_node *) i;
179		if (iterate(n, data))
180			break;
181	}
182}
183
184unsigned int queue_len(const struct queue *b)
185{
186	return b->num_elems;
187}
188