1/*	$OpenBSD: name2id.c,v 1.1 2007/01/08 13:01:10 claudio Exp $ */
2
3/*
4 * Copyright (c) 2004, 2005 Henning Brauer <henning@openbsd.org>
5 *
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER IN
15 * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
16 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 */
18
19#include <sys/types.h>
20#include <sys/socket.h>
21
22#include <net/route.h>
23
24#include <errno.h>
25#include <stdlib.h>
26#include <string.h>
27
28#include "ripd.h"
29
30#define	IDVAL_MAX	50000
31
32struct n2id_label {
33	TAILQ_ENTRY(n2id_label)	 entry;
34	char			*name;
35	u_int16_t		 id;
36	int			 ref;
37};
38
39TAILQ_HEAD(n2id_labels, n2id_label);
40
41u_int16_t	 _name2id(struct n2id_labels *, const char *);
42const char	*_id2name(struct n2id_labels *, u_int16_t);
43void		 _unref(struct n2id_labels *, u_int16_t);
44void		 _ref(struct n2id_labels *, u_int16_t);
45
46struct n2id_labels	rt_labels = TAILQ_HEAD_INITIALIZER(rt_labels);
47
48u_int16_t
49rtlabel_name2id(const char *name)
50{
51	return (_name2id(&rt_labels, name));
52}
53
54const char *
55rtlabel_id2name(u_int16_t id)
56{
57	return (_id2name(&rt_labels, id));
58}
59
60void
61rtlabel_unref(u_int16_t id)
62{
63	_unref(&rt_labels, id);
64}
65
66/*
67void
68rtlabel_ref(u_int16_t id)
69{
70	_ref(&rt_labels, id);
71}
72*/
73
74u_int16_t
75_name2id(struct n2id_labels *head, const char *name)
76{
77	struct n2id_label	*label, *p = NULL;
78	u_int16_t		 new_id = 1;
79
80	if (!name[0]) {
81		errno = EINVAL;
82		return (0);
83	}
84
85	TAILQ_FOREACH(label, head, entry)
86		if (strcmp(name, label->name) == 0) {
87			label->ref++;
88			return (label->id);
89		}
90
91	/*
92	 * to avoid fragmentation, we do a linear search from the beginning
93	 * and take the first free slot we find. if there is none or the list
94	 * is empty, append a new entry at the end.
95	 */
96
97	if (!TAILQ_EMPTY(head))
98		for (p = TAILQ_FIRST(head); p != NULL &&
99		    p->id == new_id; p = TAILQ_NEXT(p, entry))
100			new_id = p->id + 1;
101
102	if (new_id > IDVAL_MAX) {
103		errno = ERANGE;
104		return (0);
105	}
106
107	if ((label = calloc(1, sizeof(struct n2id_label))) == NULL)
108		return (0);
109	if ((label->name = strdup(name)) == NULL) {
110		free(label);
111		return (0);
112	}
113	label->id = new_id;
114	label->ref++;
115
116	if (p != NULL)	/* insert new entry before p */
117		TAILQ_INSERT_BEFORE(p, label, entry);
118	else		/* either list empty or no free slot in between */
119		TAILQ_INSERT_TAIL(head, label, entry);
120
121	return (label->id);
122}
123
124const char *
125_id2name(struct n2id_labels *head, u_int16_t id)
126{
127	struct n2id_label	*label;
128
129	if (id == 0)
130		return ("");
131
132	TAILQ_FOREACH(label, head, entry)
133		if (label->id == id)
134			return (label->name);
135
136	return ("");
137}
138
139void
140_unref(struct n2id_labels *head, u_int16_t id)
141{
142	struct n2id_label	*p, *next;
143
144	if (id == 0)
145		return;
146
147	for (p = TAILQ_FIRST(head); p != NULL; p = next) {
148		next = TAILQ_NEXT(p, entry);
149		if (id == p->id) {
150			if (--p->ref == 0) {
151				TAILQ_REMOVE(head, p, entry);
152				free(p->name);
153				free(p);
154			}
155			break;
156		}
157	}
158}
159
160void
161_ref(struct n2id_labels *head, u_int16_t id)
162{
163	struct n2id_label	*label;
164
165	if (id == 0)
166		return;
167
168	TAILQ_FOREACH(label, head, entry)
169		if (label->id == id) {
170			++label->ref;
171			break;
172		}
173}
174