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
32 struct n2id_label {
33 TAILQ_ENTRY(n2id_label) entry;
34 char *name;
35 u_int16_t id;
36 int ref;
37 };
38
39 TAILQ_HEAD(n2id_labels, n2id_label);
40
41 u_int16_t _name2id(struct n2id_labels *, const char *);
42 const char *_id2name(struct n2id_labels *, u_int16_t);
43 void _unref(struct n2id_labels *, u_int16_t);
44 void _ref(struct n2id_labels *, u_int16_t);
45
46 struct n2id_labels rt_labels = TAILQ_HEAD_INITIALIZER(rt_labels);
47
48 u_int16_t
rtlabel_name2id(const char * name)49 rtlabel_name2id(const char *name)
50 {
51 return (_name2id(&rt_labels, name));
52 }
53
54 const char *
rtlabel_id2name(u_int16_t id)55 rtlabel_id2name(u_int16_t id)
56 {
57 return (_id2name(&rt_labels, id));
58 }
59
60 void
rtlabel_unref(u_int16_t id)61 rtlabel_unref(u_int16_t id)
62 {
63 _unref(&rt_labels, id);
64 }
65
66 /*
67 void
68 rtlabel_ref(u_int16_t id)
69 {
70 _ref(&rt_labels, id);
71 }
72 */
73
74 u_int16_t
_name2id(struct n2id_labels * head,const char * name)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
124 const char *
_id2name(struct n2id_labels * head,u_int16_t id)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
139 void
_unref(struct n2id_labels * head,u_int16_t id)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
160 void
_ref(struct n2id_labels * head,u_int16_t id)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