lib/namemap.c

   1 /*
   2  * Copyright (c) 2017-2018 Nicira, Inc.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at:
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 #include <config.h>
  18 #include "openvswitch/namemap.h"
  19 #include <ctype.h>
  20 #include "hash.h"
  21 #include "openvswitch/dynamic-string.h"
  22 #include "openvswitch/json.h"
  23
  24 void
  25 namemap_init(struct namemap *map)
  26 {
  27     hmap_init(&map->by_name);
  28     hmap_init(&map->by_number);
  29 }
  30
  31 struct namemap_node *
  32 namemap_find_by_name(const struct namemap *map, const char *name)
  33 {
  34     struct namemap_node *node;
  35
  36     HMAP_FOR_EACH_WITH_HASH (node, name_node, hash_string(name, 0),
  37                              &map->by_name) {
  38         if (!strcmp(name, node->name)) {
  39             return node;
  40         }
  41     }
  42     return NULL;
  43 }
  44
  45 struct namemap_node *
  46 namemap_find_by_number(const struct namemap *map, uint32_t number)
  47 {
  48     struct namemap_node *node;
  49
  50     HMAP_FOR_EACH_IN_BUCKET (node, number_node, hash_int(number, 0),
  51                              &map->by_number) {
  52         if (node->number == number) {
  53             return node;
  54         }
  55     }
  56     return NULL;
  57 }
  58
  59 void
  60 namemap_put(struct namemap *map, uint32_t number, const char *name)
  61 {
  62     struct namemap_node *node;
  63
  64     /* Look for duplicate name. */
  65     node = namemap_find_by_name(map, name);
  66     if (node) {
  67         if (node->number != number) {
  68             node->duplicate = true;
  69         }
  70         return;
  71     }
  72
  73     /* Look for duplicate number. */
  74     node = namemap_find_by_number(map, number);
  75     if (node) {
  76         node->duplicate = true;
  77         return;
  78     }
  79
  80     /* Add new node. */
  81     node = xmalloc(sizeof *node);
  82     hmap_insert(&map->by_number, &node->number_node, hash_int(number, 0));
  83     hmap_insert(&map->by_name, &node->name_node, hash_string(name, 0));
  84     node->number = number;
  85     node->name = xstrdup(name);
  86     node->duplicate = false;
  87 }
  88
  89 void
  90 namemap_destroy(struct namemap *map)
  91 {
  92     if (map) {
  93         struct namemap_node *node, *next;
  94
  95         HMAP_FOR_EACH_SAFE (node, next, name_node, &map->by_name) {
  96             hmap_remove(&map->by_name, &node->name_node);
  97             hmap_remove(&map->by_number, &node->number_node);
  98             free(node->name);
  99             free(node);
 100         }
 101         hmap_destroy(&map->by_name);
 102         hmap_destroy(&map->by_number);
 103     }
 104 }
 105
 106 /* A table or port name doesn't need to be quoted if it is alphanumeric and
 107  * starts with a letter. */
 108 static bool
 109 name_needs_quotes(const char *name)
 110 {
 111     if (!isalpha((unsigned char) name[0])) {
 112         return true;
 113     }
 114
 115     for (const char *p = name + 1; *p; p++) {
 116         if (!isalnum((unsigned char) *p)) {
 117             return true;
 118         }
 119     }
 120     return false;
 121 }
 122
 123 /* Appends port or table 'name' to 's', quoting it if necessary. */
 124 void
 125 namemap_put_name(const char *name, struct ds *s)
 126 {
 127     if (name_needs_quotes(name)) {
 128         json_string_escape(name, s);
 129     } else {
 130         ds_put_cstr(s, name);
 131     }
 132 }