1 /* $OpenBSD: name2id.c,v 1.4 2015/01/22 17:42:09 reyk 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/queue.h> 21 22 #include <stdlib.h> 23 #include <string.h> 24 #include <errno.h> 25 26 #include "relayd.h" 27 28 #define IDVAL_MAX 50000 29 30 struct n2id_label { 31 TAILQ_ENTRY(n2id_label) entry; 32 char *name; 33 u_int16_t id; 34 int ref; 35 }; 36 37 TAILQ_HEAD(n2id_labels, n2id_label); 38 39 u_int16_t _name2id(struct n2id_labels *, const char *); 40 const char *_id2name(struct n2id_labels *, u_int16_t); 41 void _unref(struct n2id_labels *, u_int16_t); 42 void _ref(struct n2id_labels *, u_int16_t); 43 44 struct n2id_labels relay_labels = TAILQ_HEAD_INITIALIZER(relay_labels); 45 struct n2id_labels relay_tags = TAILQ_HEAD_INITIALIZER(relay_tags); 46 47 u_int16_t 48 tag_name2id(const char *name) 49 { 50 return (_name2id(&relay_tags, name)); 51 } 52 53 const char * 54 tag_id2name(u_int16_t id) 55 { 56 return (_id2name(&relay_tags, id)); 57 } 58 59 void 60 tag_unref(u_int16_t id) 61 { 62 _unref(&relay_tags, id); 63 } 64 65 void 66 tag_ref(u_int16_t id) 67 { 68 _ref(&relay_tags, id); 69 } 70 71 u_int16_t 72 label_name2id(const char *name) 73 { 74 return (_name2id(&relay_labels, name)); 75 } 76 77 const char * 78 label_id2name(u_int16_t id) 79 { 80 return (_id2name(&relay_labels, id)); 81 } 82 83 void 84 label_unref(u_int16_t id) 85 { 86 _unref(&relay_labels, id); 87 } 88 89 void 90 label_ref(u_int16_t id) 91 { 92 _ref(&relay_labels, id); 93 } 94 95 u_int16_t 96 _name2id(struct n2id_labels *head, const char *name) 97 { 98 struct n2id_label *label, *p = NULL; 99 u_int16_t new_id = 1; 100 101 if (!name[0]) { 102 errno = EINVAL; 103 return (0); 104 } 105 106 TAILQ_FOREACH(label, head, entry) 107 if (strcmp(name, label->name) == 0) { 108 label->ref++; 109 return (label->id); 110 } 111 112 /* 113 * to avoid fragmentation, we do a linear search from the beginning 114 * and take the first free slot we find. if there is none or the list 115 * is empty, append a new entry at the end. 116 */ 117 118 if (!TAILQ_EMPTY(head)) 119 for (p = TAILQ_FIRST(head); p != NULL && 120 p->id == new_id; p = TAILQ_NEXT(p, entry)) 121 new_id = p->id + 1; 122 123 if (new_id > IDVAL_MAX) { 124 errno = ERANGE; 125 return (0); 126 } 127 128 if ((label = calloc(1, sizeof(struct n2id_label))) == NULL) 129 return (0); 130 if ((label->name = strdup(name)) == NULL) { 131 free(label); 132 return (0); 133 } 134 label->id = new_id; 135 label->ref++; 136 137 if (p != NULL) /* insert new entry before p */ 138 TAILQ_INSERT_BEFORE(p, label, entry); 139 else /* either list empty or no free slot in between */ 140 TAILQ_INSERT_TAIL(head, label, entry); 141 142 return (label->id); 143 } 144 145 const char * 146 _id2name(struct n2id_labels *head, u_int16_t id) 147 { 148 struct n2id_label *label; 149 150 if (id == 0) 151 return (""); 152 153 TAILQ_FOREACH(label, head, entry) 154 if (label->id == id) 155 return (label->name); 156 157 return (""); 158 } 159 160 void 161 _unref(struct n2id_labels *head, u_int16_t id) 162 { 163 struct n2id_label *p, *next; 164 165 if (id == 0) 166 return; 167 168 for (p = TAILQ_FIRST(head); p != NULL; p = next) { 169 next = TAILQ_NEXT(p, entry); 170 if (id == p->id) { 171 if (--p->ref == 0) { 172 TAILQ_REMOVE(head, p, entry); 173 free(p->name); 174 free(p); 175 } 176 break; 177 } 178 } 179 } 180 181 void 182 _ref(struct n2id_labels *head, u_int16_t id) 183 { 184 struct n2id_label *label; 185 186 if (id == 0) 187 return; 188 189 TAILQ_FOREACH(label, head, entry) 190 if (label->id == id) { 191 ++label->ref; 192 break; 193 } 194 } 195