1 /* Copyright (c) 2009, 2010, 2011 Nicira Networks
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:
7 * http://www.apache.org/licenses/LICENSE-2.0
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.
22 #include "ovsdb-error.h"
23 #include "ovsdb-parser.h"
24 #include "ovsdb-types.h"
26 #include "transaction.h"
29 ovsdb_schema_create(const char *name, const char *version, const char *cksum)
31 struct ovsdb_schema *schema;
33 schema = xzalloc(sizeof *schema);
34 schema->name = xstrdup(name);
35 schema->version = xstrdup(version);
36 schema->cksum = xstrdup(cksum);
37 shash_init(&schema->tables);
43 ovsdb_schema_clone(const struct ovsdb_schema *old)
45 struct ovsdb_schema *new;
46 struct shash_node *node;
48 new = ovsdb_schema_create(old->name, old->version, old->cksum);
49 SHASH_FOR_EACH (node, &old->tables) {
50 const struct ovsdb_table_schema *ts = node->data;
52 shash_add(&new->tables, node->name, ovsdb_table_schema_clone(ts));
58 ovsdb_schema_destroy(struct ovsdb_schema *schema)
60 struct shash_node *node;
66 SHASH_FOR_EACH (node, &schema->tables) {
67 ovsdb_table_schema_destroy(node->data);
69 shash_destroy(&schema->tables);
71 free(schema->version);
77 ovsdb_schema_from_file(const char *file_name, struct ovsdb_schema **schemap)
79 struct ovsdb_schema *schema;
80 struct ovsdb_error *error;
84 json = json_from_file(file_name);
85 if (json->type == JSON_STRING) {
86 error = ovsdb_error("failed to read schema",
87 "\"%s\" could not be read as JSON (%s)",
88 file_name, json_string(json));
93 error = ovsdb_schema_from_json(json, &schema);
96 return ovsdb_wrap_error(error,
97 "failed to parse \"%s\" as ovsdb schema",
105 static struct ovsdb_error * WARN_UNUSED_RESULT
106 ovsdb_schema_check_ref_table(struct ovsdb_column *column,
107 const struct shash *tables,
108 const struct ovsdb_base_type *base,
109 const char *base_name)
111 struct ovsdb_table_schema *refTable;
113 if (base->type != OVSDB_TYPE_UUID || !base->u.uuid.refTableName) {
117 refTable = shash_find_data(tables, base->u.uuid.refTableName);
119 return ovsdb_syntax_error(NULL, NULL,
120 "column %s %s refers to undefined table %s",
121 column->name, base_name,
122 base->u.uuid.refTableName);
125 if (ovsdb_base_type_is_strong_ref(base) && !refTable->is_root) {
126 /* We cannot allow a strong reference to a non-root table to be
127 * ephemeral: if it is the only reference to a row, then replaying the
128 * database log from disk will cause the referenced row to be deleted,
129 * even though it did exist in memory. If there are references to that
130 * row later in the log (to modify it, to delete it, or just to point
131 * to it), then this will yield a transaction error. */
132 column->persistent = true;
139 is_valid_version(const char *s)
142 ignore(sscanf(s, "%*[0-9].%*[0-9].%*[0-9]%n", &n));
143 return n != -1 && s[n] == '\0';
146 /* Returns the number of tables in 'schema''s root set. */
148 root_set_size(const struct ovsdb_schema *schema)
150 struct shash_node *node;
153 SHASH_FOR_EACH (node, &schema->tables) {
154 struct ovsdb_table_schema *table = node->data;
156 n_root += table->is_root;
162 ovsdb_schema_from_json(struct json *json, struct ovsdb_schema **schemap)
164 struct ovsdb_schema *schema;
165 const struct json *name, *tables, *version_json, *cksum;
166 struct ovsdb_error *error;
167 struct shash_node *node;
168 struct ovsdb_parser parser;
173 ovsdb_parser_init(&parser, json, "database schema");
174 name = ovsdb_parser_member(&parser, "name", OP_ID);
175 version_json = ovsdb_parser_member(&parser, "version",
176 OP_STRING | OP_OPTIONAL);
177 cksum = ovsdb_parser_member(&parser, "cksum", OP_STRING | OP_OPTIONAL);
178 tables = ovsdb_parser_member(&parser, "tables", OP_OBJECT);
179 error = ovsdb_parser_finish(&parser);
185 version = json_string(version_json);
186 if (!is_valid_version(version)) {
187 return ovsdb_syntax_error(json, NULL, "schema version \"%s\" not "
188 "in format x.y.z", version);
191 /* Backward compatibility with old databases. */
195 schema = ovsdb_schema_create(json_string(name), version,
196 cksum ? json_string(cksum) : "");
197 SHASH_FOR_EACH (node, json_object(tables)) {
198 struct ovsdb_table_schema *table;
200 if (node->name[0] == '_') {
201 error = ovsdb_syntax_error(json, NULL, "names beginning with "
202 "\"_\" are reserved");
203 } else if (!ovsdb_parser_is_id(node->name)) {
204 error = ovsdb_syntax_error(json, NULL, "name must be a valid id");
206 error = ovsdb_table_schema_from_json(node->data, node->name,
210 ovsdb_schema_destroy(schema);
214 shash_add(&schema->tables, table->name, table);
217 /* "isRoot" was not part of the original schema definition. Before it was
218 * added, there was no support for garbage collection. So, for backward
219 * compatibility, if the root set is empty then assume that every table is
220 * in the root set. */
221 if (root_set_size(schema) == 0) {
222 SHASH_FOR_EACH (node, &schema->tables) {
223 struct ovsdb_table_schema *table = node->data;
225 table->is_root = true;
229 /* Validate that all refTables refer to the names of tables that exist.
231 * Also force certain columns to be persistent, as explained in
232 * ovsdb_schema_check_ref_table(). This requires 'is_root' to be known, so
233 * this must follow the loop updating 'is_root' above. */
234 SHASH_FOR_EACH (node, &schema->tables) {
235 struct ovsdb_table_schema *table = node->data;
236 struct shash_node *node2;
238 SHASH_FOR_EACH (node2, &table->columns) {
239 struct ovsdb_column *column = node2->data;
241 error = ovsdb_schema_check_ref_table(column, &schema->tables,
242 &column->type.key, "key");
244 error = ovsdb_schema_check_ref_table(column, &schema->tables,
249 ovsdb_schema_destroy(schema);
260 ovsdb_schema_to_json(const struct ovsdb_schema *schema)
262 struct json *json, *tables;
263 struct shash_node *node;
264 bool default_is_root;
266 json = json_object_create();
267 json_object_put_string(json, "name", schema->name);
268 if (schema->version[0]) {
269 json_object_put_string(json, "version", schema->version);
271 if (schema->cksum[0]) {
272 json_object_put_string(json, "cksum", schema->cksum);
275 /* "isRoot" was not part of the original schema definition. Before it was
276 * added, there was no support for garbage collection. So, for backward
277 * compatibility, if every table is in the root set then do not output
278 * "isRoot" in table schemas. */
279 default_is_root = root_set_size(schema) == shash_count(&schema->tables);
281 tables = json_object_create();
283 SHASH_FOR_EACH (node, &schema->tables) {
284 struct ovsdb_table_schema *table = node->data;
285 json_object_put(tables, table->name,
286 ovsdb_table_schema_to_json(table, default_is_root));
288 json_object_put(json, "tables", tables);
293 /* Returns true if 'a' and 'b' specify equivalent schemas, false if they
296 ovsdb_schema_equal(const struct ovsdb_schema *a,
297 const struct ovsdb_schema *b)
299 /* This implementation is simple, stupid, and slow, but I doubt that it
300 * will ever require much maintenance. */
301 struct json *ja = ovsdb_schema_to_json(a);
302 struct json *jb = ovsdb_schema_to_json(b);
303 bool equals = json_equal(ja, jb);
311 ovsdb_set_ref_table(const struct shash *tables,
312 struct ovsdb_base_type *base)
314 if (base->type == OVSDB_TYPE_UUID && base->u.uuid.refTableName) {
315 struct ovsdb_table *table;
317 table = shash_find_data(tables, base->u.uuid.refTableName);
318 base->u.uuid.refTable = table;
323 ovsdb_create(struct ovsdb_schema *schema)
325 struct shash_node *node;
328 db = xmalloc(sizeof *db);
330 list_init(&db->replicas);
331 list_init(&db->triggers);
332 db->run_triggers = false;
334 shash_init(&db->tables);
335 SHASH_FOR_EACH (node, &schema->tables) {
336 struct ovsdb_table_schema *ts = node->data;
337 shash_add(&db->tables, node->name, ovsdb_table_create(ts));
340 /* Set all the refTables. */
341 SHASH_FOR_EACH (node, &schema->tables) {
342 struct ovsdb_table_schema *table = node->data;
343 struct shash_node *node2;
345 SHASH_FOR_EACH (node2, &table->columns) {
346 struct ovsdb_column *column = node2->data;
348 ovsdb_set_ref_table(&db->tables, &column->type.key);
349 ovsdb_set_ref_table(&db->tables, &column->type.value);
357 ovsdb_destroy(struct ovsdb *db)
360 struct shash_node *node;
362 /* Remove all the replicas. */
363 while (!list_is_empty(&db->replicas)) {
364 struct ovsdb_replica *r
365 = CONTAINER_OF(list_pop_back(&db->replicas),
366 struct ovsdb_replica, node);
367 ovsdb_remove_replica(db, r);
370 /* Delete all the tables. This also deletes their schemas. */
371 SHASH_FOR_EACH (node, &db->tables) {
372 struct ovsdb_table *table = node->data;
373 ovsdb_table_destroy(table);
375 shash_destroy(&db->tables);
377 /* The schemas, but not the table that points to them, were deleted in
378 * the previous step, so we need to clear out the table. We can't
379 * destroy the table, because ovsdb_schema_destroy() will do that. */
380 shash_clear(&db->schema->tables);
382 ovsdb_schema_destroy(db->schema);
388 ovsdb_get_table(const struct ovsdb *db, const char *name)
390 return shash_find_data(&db->tables, name);
394 ovsdb_replica_init(struct ovsdb_replica *r,
395 const struct ovsdb_replica_class *class)
401 ovsdb_add_replica(struct ovsdb *db, struct ovsdb_replica *r)
403 list_push_back(&db->replicas, &r->node);
407 ovsdb_remove_replica(struct ovsdb *db OVS_UNUSED, struct ovsdb_replica *r)
409 list_remove(&r->node);
410 (r->class->destroy)(r);