2
0
mirror of https://github.com/openvswitch/ovs synced 2025-10-27 15:18:06 +00:00
Files
openvswitch/ovsdb/ovsdb.c
2013-11-15 08:55:02 -08:00

432 lines
13 KiB
C
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/* Copyright (c) 2009, 2010, 2011, 2012, 2013 Nicira, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <config.h>
#include "ovsdb.h"
#include "column.h"
#include "json.h"
#include "ovsdb-error.h"
#include "ovsdb-parser.h"
#include "ovsdb-types.h"
#include "simap.h"
#include "table.h"
#include "transaction.h"
struct ovsdb_schema *
ovsdb_schema_create(const char *name, const char *version, const char *cksum)
{
struct ovsdb_schema *schema;
schema = xzalloc(sizeof *schema);
schema->name = xstrdup(name);
schema->version = xstrdup(version);
schema->cksum = xstrdup(cksum);
shash_init(&schema->tables);
return schema;
}
struct ovsdb_schema *
ovsdb_schema_clone(const struct ovsdb_schema *old)
{
struct ovsdb_schema *new;
struct shash_node *node;
new = ovsdb_schema_create(old->name, old->version, old->cksum);
SHASH_FOR_EACH (node, &old->tables) {
const struct ovsdb_table_schema *ts = node->data;
shash_add(&new->tables, node->name, ovsdb_table_schema_clone(ts));
}
return new;
}
void
ovsdb_schema_destroy(struct ovsdb_schema *schema)
{
struct shash_node *node;
if (!schema) {
return;
}
SHASH_FOR_EACH (node, &schema->tables) {
ovsdb_table_schema_destroy(node->data);
}
shash_destroy(&schema->tables);
free(schema->name);
free(schema->version);
free(schema->cksum);
free(schema);
}
struct ovsdb_error *
ovsdb_schema_from_file(const char *file_name, struct ovsdb_schema **schemap)
{
struct ovsdb_schema *schema;
struct ovsdb_error *error;
struct json *json;
*schemap = NULL;
json = json_from_file(file_name);
if (json->type == JSON_STRING) {
error = ovsdb_error("failed to read schema",
"\"%s\" could not be read as JSON (%s)",
file_name, json_string(json));
json_destroy(json);
return error;
}
error = ovsdb_schema_from_json(json, &schema);
json_destroy(json);
if (error) {
return ovsdb_wrap_error(error,
"failed to parse \"%s\" as ovsdb schema",
file_name);
}
*schemap = schema;
return NULL;
}
static struct ovsdb_error * WARN_UNUSED_RESULT
ovsdb_schema_check_ref_table(struct ovsdb_column *column,
const struct shash *tables,
const struct ovsdb_base_type *base,
const char *base_name)
{
struct ovsdb_table_schema *refTable;
if (base->type != OVSDB_TYPE_UUID || !base->u.uuid.refTableName) {
return NULL;
}
refTable = shash_find_data(tables, base->u.uuid.refTableName);
if (!refTable) {
return ovsdb_syntax_error(NULL, NULL,
"column %s %s refers to undefined table %s",
column->name, base_name,
base->u.uuid.refTableName);
}
if (ovsdb_base_type_is_strong_ref(base) && !refTable->is_root) {
/* We cannot allow a strong reference to a non-root table to be
* ephemeral: if it is the only reference to a row, then replaying the
* database log from disk will cause the referenced row to be deleted,
* even though it did exist in memory. If there are references to that
* row later in the log (to modify it, to delete it, or just to point
* to it), then this will yield a transaction error. */
column->persistent = true;
}
return NULL;
}
static bool
is_valid_version(const char *s)
{
int n = -1;
ignore(ovs_scan(s, "%*[0-9].%*[0-9].%*[0-9]%n", &n));
return n != -1 && s[n] == '\0';
}
/* Returns the number of tables in 'schema''s root set. */
static size_t
root_set_size(const struct ovsdb_schema *schema)
{
struct shash_node *node;
size_t n_root = 0;
SHASH_FOR_EACH (node, &schema->tables) {
struct ovsdb_table_schema *table = node->data;
n_root += table->is_root;
}
return n_root;
}
struct ovsdb_error *
ovsdb_schema_from_json(struct json *json, struct ovsdb_schema **schemap)
{
struct ovsdb_schema *schema;
const struct json *name, *tables, *version_json, *cksum;
struct ovsdb_error *error;
struct shash_node *node;
struct ovsdb_parser parser;
const char *version;
*schemap = NULL;
ovsdb_parser_init(&parser, json, "database schema");
name = ovsdb_parser_member(&parser, "name", OP_ID);
version_json = ovsdb_parser_member(&parser, "version",
OP_STRING | OP_OPTIONAL);
cksum = ovsdb_parser_member(&parser, "cksum", OP_STRING | OP_OPTIONAL);
tables = ovsdb_parser_member(&parser, "tables", OP_OBJECT);
error = ovsdb_parser_finish(&parser);
if (error) {
return error;
}
if (version_json) {
version = json_string(version_json);
if (!is_valid_version(version)) {
return ovsdb_syntax_error(json, NULL, "schema version \"%s\" not "
"in format x.y.z", version);
}
} else {
/* Backward compatibility with old databases. */
version = "";
}
schema = ovsdb_schema_create(json_string(name), version,
cksum ? json_string(cksum) : "");
SHASH_FOR_EACH (node, json_object(tables)) {
struct ovsdb_table_schema *table;
if (node->name[0] == '_') {
error = ovsdb_syntax_error(json, NULL, "names beginning with "
"\"_\" are reserved");
} else if (!ovsdb_parser_is_id(node->name)) {
error = ovsdb_syntax_error(json, NULL, "name must be a valid id");
} else {
error = ovsdb_table_schema_from_json(node->data, node->name,
&table);
}
if (error) {
ovsdb_schema_destroy(schema);
return error;
}
shash_add(&schema->tables, table->name, table);
}
/* "isRoot" was not part of the original schema definition. Before it was
* added, there was no support for garbage collection. So, for backward
* compatibility, if the root set is empty then assume that every table is
* in the root set. */
if (root_set_size(schema) == 0) {
SHASH_FOR_EACH (node, &schema->tables) {
struct ovsdb_table_schema *table = node->data;
table->is_root = true;
}
}
/* Validate that all refTables refer to the names of tables that exist.
*
* Also force certain columns to be persistent, as explained in
* ovsdb_schema_check_ref_table(). This requires 'is_root' to be known, so
* this must follow the loop updating 'is_root' above. */
SHASH_FOR_EACH (node, &schema->tables) {
struct ovsdb_table_schema *table = node->data;
struct shash_node *node2;
SHASH_FOR_EACH (node2, &table->columns) {
struct ovsdb_column *column = node2->data;
error = ovsdb_schema_check_ref_table(column, &schema->tables,
&column->type.key, "key");
if (!error) {
error = ovsdb_schema_check_ref_table(column, &schema->tables,
&column->type.value,
"value");
}
if (error) {
ovsdb_schema_destroy(schema);
return error;
}
}
}
*schemap = schema;
return NULL;
}
struct json *
ovsdb_schema_to_json(const struct ovsdb_schema *schema)
{
struct json *json, *tables;
struct shash_node *node;
bool default_is_root;
json = json_object_create();
json_object_put_string(json, "name", schema->name);
if (schema->version[0]) {
json_object_put_string(json, "version", schema->version);
}
if (schema->cksum[0]) {
json_object_put_string(json, "cksum", schema->cksum);
}
/* "isRoot" was not part of the original schema definition. Before it was
* added, there was no support for garbage collection. So, for backward
* compatibility, if every table is in the root set then do not output
* "isRoot" in table schemas. */
default_is_root = root_set_size(schema) == shash_count(&schema->tables);
tables = json_object_create();
SHASH_FOR_EACH (node, &schema->tables) {
struct ovsdb_table_schema *table = node->data;
json_object_put(tables, table->name,
ovsdb_table_schema_to_json(table, default_is_root));
}
json_object_put(json, "tables", tables);
return json;
}
/* Returns true if 'a' and 'b' specify equivalent schemas, false if they
* differ. */
bool
ovsdb_schema_equal(const struct ovsdb_schema *a,
const struct ovsdb_schema *b)
{
/* This implementation is simple, stupid, and slow, but I doubt that it
* will ever require much maintenance. */
struct json *ja = ovsdb_schema_to_json(a);
struct json *jb = ovsdb_schema_to_json(b);
bool equals = json_equal(ja, jb);
json_destroy(ja);
json_destroy(jb);
return equals;
}
static void
ovsdb_set_ref_table(const struct shash *tables,
struct ovsdb_base_type *base)
{
if (base->type == OVSDB_TYPE_UUID && base->u.uuid.refTableName) {
struct ovsdb_table *table;
table = shash_find_data(tables, base->u.uuid.refTableName);
base->u.uuid.refTable = table;
}
}
struct ovsdb *
ovsdb_create(struct ovsdb_schema *schema)
{
struct shash_node *node;
struct ovsdb *db;
db = xmalloc(sizeof *db);
db->schema = schema;
list_init(&db->replicas);
list_init(&db->triggers);
db->run_triggers = false;
shash_init(&db->tables);
SHASH_FOR_EACH (node, &schema->tables) {
struct ovsdb_table_schema *ts = node->data;
shash_add(&db->tables, node->name, ovsdb_table_create(ts));
}
/* Set all the refTables. */
SHASH_FOR_EACH (node, &schema->tables) {
struct ovsdb_table_schema *table = node->data;
struct shash_node *node2;
SHASH_FOR_EACH (node2, &table->columns) {
struct ovsdb_column *column = node2->data;
ovsdb_set_ref_table(&db->tables, &column->type.key);
ovsdb_set_ref_table(&db->tables, &column->type.value);
}
}
return db;
}
void
ovsdb_destroy(struct ovsdb *db)
{
if (db) {
struct shash_node *node;
/* Remove all the replicas. */
while (!list_is_empty(&db->replicas)) {
struct ovsdb_replica *r
= CONTAINER_OF(list_pop_back(&db->replicas),
struct ovsdb_replica, node);
ovsdb_remove_replica(db, r);
}
/* Delete all the tables. This also deletes their schemas. */
SHASH_FOR_EACH (node, &db->tables) {
struct ovsdb_table *table = node->data;
ovsdb_table_destroy(table);
}
shash_destroy(&db->tables);
/* The schemas, but not the table that points to them, were deleted in
* the previous step, so we need to clear out the table. We can't
* destroy the table, because ovsdb_schema_destroy() will do that. */
shash_clear(&db->schema->tables);
ovsdb_schema_destroy(db->schema);
free(db);
}
}
/* Adds some memory usage statistics for 'db' into 'usage', for use with
* memory_report(). */
void
ovsdb_get_memory_usage(const struct ovsdb *db, struct simap *usage)
{
const struct shash_node *node;
unsigned int cells = 0;
SHASH_FOR_EACH (node, &db->tables) {
const struct ovsdb_table *table = node->data;
unsigned int n_columns = shash_count(&table->schema->columns);
unsigned int n_rows = hmap_count(&table->rows);
cells += n_rows * n_columns;
}
simap_increase(usage, "cells", cells);
}
struct ovsdb_table *
ovsdb_get_table(const struct ovsdb *db, const char *name)
{
return shash_find_data(&db->tables, name);
}
void
ovsdb_replica_init(struct ovsdb_replica *r,
const struct ovsdb_replica_class *class)
{
r->class = class;
}
void
ovsdb_add_replica(struct ovsdb *db, struct ovsdb_replica *r)
{
list_push_back(&db->replicas, &r->node);
}
void
ovsdb_remove_replica(struct ovsdb *db OVS_UNUSED, struct ovsdb_replica *r)
{
list_remove(&r->node);
(r->class->destroy)(r);
}