ovsdb/table.c

   1 /* Copyright (c) 2009 Nicira Networks
   2  *
   3  * Licensed under the Apache License, Version 2.0 (the "License");
   4  * you may not use this file except in compliance with the License.
   5  * You may obtain a copy of the License at:
   6  *
   7  *     http://www.apache.org/licenses/LICENSE-2.0
   8  *
   9  * Unless required by applicable law or agreed to in writing, software
  10  * distributed under the License is distributed on an "AS IS" BASIS,
  11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12  * See the License for the specific language governing permissions and
  13  * limitations under the License.
  14  */
  15
  16 #include <config.h>
  17
  18 #include "table.h"
  19
  20 #include <assert.h>
  21
  22 #include "json.h"
  23 #include "column.h"
  24 #include "ovsdb-error.h"
  25 #include "ovsdb-parser.h"
  26 #include "ovsdb-types.h"
  27 #include "row.h"
  28
  29 static void
  30 add_column(struct ovsdb_table_schema *ts, struct ovsdb_column *column)
  31 {
  32     assert(!shash_find(&ts->columns, column->name));
  33     column->index = shash_count(&ts->columns);
  34     shash_add(&ts->columns, column->name, column);
  35 }
  36
  37 struct ovsdb_table_schema *
  38 ovsdb_table_schema_create(const char *name, const char *comment, bool mutable)
  39 {
  40     struct ovsdb_column *uuid, *version;
  41     struct ovsdb_table_schema *ts;
  42
  43     ts = xzalloc(sizeof *ts);
  44     ts->name = xstrdup(name);
  45     ts->comment = comment ? xstrdup(comment) : NULL;
  46     ts->mutable = mutable;
  47     shash_init(&ts->columns);
  48
  49     uuid = ovsdb_column_create(
  50         "_uuid", "Unique identifier for this row.",
  51         false, true, &ovsdb_type_uuid);
  52     add_column(ts, uuid);
  53     assert(uuid->index == OVSDB_COL_UUID);
  54
  55     version = ovsdb_column_create(
  56         "_version", "Unique identifier for this version of this row.",
  57         false, false, &ovsdb_type_uuid);
  58     add_column(ts, version);
  59     assert(version->index == OVSDB_COL_VERSION);
  60
  61     return ts;
  62 }
  63
  64 void
  65 ovsdb_table_schema_destroy(struct ovsdb_table_schema *ts)
  66 {
  67     struct shash_node *node;
  68
  69     SHASH_FOR_EACH (node, &ts->columns) {
  70         ovsdb_column_destroy(node->data);
  71     }
  72     shash_destroy(&ts->columns);
  73     free(ts->comment);
  74     free(ts->name);
  75     free(ts);
  76 }
  77
  78 struct ovsdb_error *
  79 ovsdb_table_schema_from_json(const struct json *json, const char *name,
  80                              struct ovsdb_table_schema **tsp)
  81 {
  82     struct ovsdb_table_schema *ts;
  83     const struct json *comment, *columns, *mutable;
  84     struct shash_node *node;
  85     struct ovsdb_parser parser;
  86     struct ovsdb_error *error;
  87
  88     *tsp = NULL;
  89
  90     ovsdb_parser_init(&parser, json, "table schema for table %s", name);
  91     comment = ovsdb_parser_member(&parser, "comment", OP_STRING | OP_OPTIONAL);
  92     columns = ovsdb_parser_member(&parser, "columns", OP_OBJECT);
  93     mutable = ovsdb_parser_member(&parser, "mutable",
  94                                   OP_TRUE | OP_FALSE | OP_OPTIONAL);
  95     error = ovsdb_parser_finish(&parser);
  96     if (error) {
  97         return error;
  98     }
  99
 100     if (shash_is_empty(json_object(columns))) {
 101         return ovsdb_syntax_error(json, NULL,
 102                                   "table must have at least one column");
 103     }
 104
 105     ts = ovsdb_table_schema_create(name,
 106                                    comment ? json_string(comment) : NULL,
 107                                    mutable ? json_boolean(mutable) : true);
 108     SHASH_FOR_EACH (node, json_object(columns)) {
 109         struct ovsdb_column *column;
 110
 111         if (node->name[0] == '_') {
 112             error = ovsdb_syntax_error(json, NULL, "names beginning with "
 113                                        "\"_\" are reserved");
 114         } else {
 115             error = ovsdb_column_from_json(node->data, node->name, &column);
 116         }
 117         if (error) {
 118             ovsdb_table_schema_destroy(ts);
 119             return error;
 120         }
 121
 122         add_column(ts, column);
 123     }
 124     *tsp = ts;
 125     return 0;
 126 }
 127
 128 struct json *
 129 ovsdb_table_schema_to_json(const struct ovsdb_table_schema *ts)
 130 {
 131     struct json *json, *columns;
 132     struct shash_node *node;
 133
 134     json = json_object_create();
 135     if (ts->comment) {
 136         json_object_put_string(json, "comment", ts->comment);
 137     }
 138     if (!ts->mutable) {
 139         json_object_put(json, "mutable", json_boolean_create(false));
 140     }
 141
 142     columns = json_object_create();
 143
 144     SHASH_FOR_EACH (node, &ts->columns) {
 145         struct ovsdb_column *column = node->data;
 146         if (node->name[0] != '_') {
 147             json_object_put(columns, column->name,
 148                             ovsdb_column_to_json(column));
 149         }
 150     }
 151     json_object_put(json, "columns", columns);
 152
 153     return json;
 154 }
 155
 156 const struct ovsdb_column *
 157 ovsdb_table_schema_get_column(const struct ovsdb_table_schema *ts,
 158                               const char *name)
 159 {
 160     return shash_find_data(&ts->columns, name);
 161 }
 162 \f
 163 struct ovsdb_table *
 164 ovsdb_table_create(struct ovsdb_table_schema *ts)
 165 {
 166     struct ovsdb_table *table;
 167
 168     table = xmalloc(sizeof *table);
 169     table->schema = ts;
 170     hmap_init(&table->rows);
 171
 172     return table;
 173 }
 174
 175 void
 176 ovsdb_table_destroy(struct ovsdb_table *table)
 177 {
 178     if (table) {
 179         struct ovsdb_row *row, *next;
 180
 181         HMAP_FOR_EACH_SAFE (row, next, struct ovsdb_row, hmap_node,
 182                             &table->rows) {
 183             ovsdb_row_destroy(row);
 184         }
 185         hmap_destroy(&table->rows);
 186
 187         ovsdb_table_schema_destroy(table->schema);
 188         free(table);
 189     }
 190 }
 191
 192 static const struct ovsdb_row *
 193 ovsdb_table_get_row__(const struct ovsdb_table *table, const struct uuid *uuid,
 194                       size_t hash)
 195 {
 196     struct ovsdb_row *row;
 197
 198     HMAP_FOR_EACH_WITH_HASH (row, struct ovsdb_row, hmap_node, hash,
 199                              &table->rows) {
 200         if (uuid_equals(ovsdb_row_get_uuid(row), uuid)) {
 201             return row;
 202         }
 203     }
 204
 205     return NULL;
 206 }
 207
 208 const struct ovsdb_row *
 209 ovsdb_table_get_row(const struct ovsdb_table *table, const struct uuid *uuid)
 210 {
 211     return ovsdb_table_get_row__(table, uuid, uuid_hash(uuid));
 212 }
 213
 214 /* This is probably not the function you want.  Use ovsdb_txn_row_modify()
 215  * instead. */
 216 bool
 217 ovsdb_table_put_row(struct ovsdb_table *table, struct ovsdb_row *row)
 218 {
 219     const struct uuid *uuid = ovsdb_row_get_uuid(row);
 220     size_t hash = uuid_hash(uuid);
 221
 222     if (!ovsdb_table_get_row__(table, uuid, hash)) {
 223         hmap_insert(&table->rows, &row->hmap_node, hash);
 224         return true;
 225     } else {
 226         return false;
 227     }
 228 }