+ return xasprintf("\"%s\": table \"%s\" has no column \"%s\"",
+ name_, table_name, column_name);
+ }
+
+ *dbp = db;
+ *columnp = column;
+ *tablep = table;
+ return NULL;
+}
+
+/* Returns NULL if successful, otherwise a malloc()'d string describing the
+ * error. */
+static char * WARN_UNUSED_RESULT
+parse_db_column(const struct db dbs[], size_t n_dbs,
+ const char *name_,
+ const struct db **dbp,
+ const struct ovsdb_table **tablep,
+ const struct ovsdb_column **columnp)
+{
+ char *name = xstrdup(name_);
+ char *retval = parse_db_column__(dbs, n_dbs, name_, name,
+ dbp, tablep, columnp);
+ free(name);
+ return retval;
+}
+
+/* Returns NULL if successful, otherwise a malloc()'d string describing the
+ * error. */
+static char * WARN_UNUSED_RESULT
+parse_db_string_column(const struct db dbs[], size_t n_dbs,
+ const char *name,
+ const struct db **dbp,
+ const struct ovsdb_table **tablep,
+ const struct ovsdb_column **columnp)
+{
+ char *retval;
+
+ retval = parse_db_column(dbs, n_dbs, name, dbp, tablep, columnp);
+ if (retval) {
+ return retval;
+ }
+
+ if ((*columnp)->type.key.type != OVSDB_TYPE_STRING
+ || (*columnp)->type.value.type != OVSDB_TYPE_VOID) {
+ return xasprintf("\"%s\": table \"%s\" column \"%s\" is "
+ "not string or set of strings",
+ name, (*tablep)->schema->name, (*columnp)->name);
+ }
+
+ return NULL;
+}
+
+static OVS_UNUSED const char *
+query_db_string(const struct db dbs[], size_t n_dbs, const char *name)
+{
+ if (!name || strncmp(name, "db:", 3)) {
+ return name;
+ } else {
+ const struct ovsdb_column *column;
+ const struct ovsdb_table *table;
+ const struct ovsdb_row *row;
+ const struct db *db;
+ char *retval;
+
+ retval = parse_db_string_column(dbs, n_dbs, name,
+ &db, &table, &column);
+ if (retval) {
+ ovs_fatal(0, "%s", retval);
+ }
+
+ HMAP_FOR_EACH (row, hmap_node, &table->rows) {
+ const struct ovsdb_datum *datum;
+ size_t i;
+
+ datum = &row->fields[column->index];
+ for (i = 0; i < datum->n; i++) {
+ if (datum->keys[i].string[0]) {
+ return datum->keys[i].string;
+ }
+ }
+ }
+ return NULL;
+ }
+}
+
+static struct ovsdb_jsonrpc_options *
+add_remote(struct shash *remotes, const char *target)
+{
+ struct ovsdb_jsonrpc_options *options;
+
+ options = shash_find_data(remotes, target);
+ if (!options) {
+ options = ovsdb_jsonrpc_default_options(target);
+ shash_add(remotes, target, options);
+ }
+
+ return options;
+}
+
+static struct ovsdb_datum *
+get_datum(struct ovsdb_row *row, const char *column_name,
+ const enum ovsdb_atomic_type key_type,
+ const enum ovsdb_atomic_type value_type,
+ const size_t n_max)
+{
+ static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 1);
+ const struct ovsdb_table_schema *schema = row->table->schema;
+ const struct ovsdb_column *column;
+
+ column = ovsdb_table_schema_get_column(schema, column_name);
+ if (!column) {
+ VLOG_DBG_RL(&rl, "Table `%s' has no `%s' column",
+ schema->name, column_name);
+ return NULL;
+ }
+
+ if (column->type.key.type != key_type
+ || column->type.value.type != value_type
+ || column->type.n_max != n_max) {
+ if (!VLOG_DROP_DBG(&rl)) {
+ char *type_name = ovsdb_type_to_english(&column->type);
+ VLOG_DBG("Table `%s' column `%s' has type %s, not expected "
+ "key type %s, value type %s, max elements %zd.",
+ schema->name, column_name, type_name,
+ ovsdb_atomic_type_to_string(key_type),
+ ovsdb_atomic_type_to_string(value_type),
+ n_max);
+ free(type_name);
+ }
+ return NULL;
+ }
+
+ return &row->fields[column->index];
+}
+
+/* Read string-string key-values from a map. Returns the value associated with
+ * 'key', if found, or NULL */
+static const char *
+read_map_string_column(const struct ovsdb_row *row, const char *column_name,
+ const char *key)
+{
+ const struct ovsdb_datum *datum;
+ union ovsdb_atom *atom_key = NULL, *atom_value = NULL;
+ size_t i;
+
+ datum = get_datum(CONST_CAST(struct ovsdb_row *, row), column_name,
+ OVSDB_TYPE_STRING, OVSDB_TYPE_STRING, UINT_MAX);
+
+ if (!datum) {
+ return NULL;
+ }
+
+ for (i = 0; i < datum->n; i++) {
+ atom_key = &datum->keys[i];
+ if (!strcmp(atom_key->string, key)){
+ atom_value = &datum->values[i];
+ break;
+ }
+ }
+
+ return atom_value ? atom_value->string : NULL;
+}
+
+static const union ovsdb_atom *
+read_column(const struct ovsdb_row *row, const char *column_name,
+ enum ovsdb_atomic_type type)
+{
+ const struct ovsdb_datum *datum;
+
+ datum = get_datum(CONST_CAST(struct ovsdb_row *, row), column_name, type,
+ OVSDB_TYPE_VOID, 1);
+ return datum && datum->n ? datum->keys : NULL;
+}
+
+static bool
+read_integer_column(const struct ovsdb_row *row, const char *column_name,
+ long long int *integerp)
+{
+ const union ovsdb_atom *atom;
+
+ atom = read_column(row, column_name, OVSDB_TYPE_INTEGER);
+ *integerp = atom ? atom->integer : 0;
+ return atom != NULL;
+}
+
+static bool
+read_string_column(const struct ovsdb_row *row, const char *column_name,
+ const char **stringp)
+{
+ const union ovsdb_atom *atom;
+
+ atom = read_column(row, column_name, OVSDB_TYPE_STRING);
+ *stringp = atom ? atom->string : NULL;
+ return atom != NULL;
+}
+
+static void
+write_bool_column(struct ovsdb_row *row, const char *column_name, bool value)
+{
+ const struct ovsdb_column *column;
+ struct ovsdb_datum *datum;
+
+ column = ovsdb_table_schema_get_column(row->table->schema, column_name);
+ datum = get_datum(row, column_name, OVSDB_TYPE_BOOLEAN,
+ OVSDB_TYPE_VOID, 1);
+ if (!datum) {
+ return;
+ }
+
+ if (datum->n != 1) {
+ ovsdb_datum_destroy(datum, &column->type);
+
+ datum->n = 1;
+ datum->keys = xmalloc(sizeof *datum->keys);
+ datum->values = NULL;
+ }
+
+ datum->keys[0].boolean = value;
+}
+
+static void
+write_string_string_column(struct ovsdb_row *row, const char *column_name,
+ char **keys, char **values, size_t n)
+{
+ const struct ovsdb_column *column;
+ struct ovsdb_datum *datum;
+ size_t i;
+
+ column = ovsdb_table_schema_get_column(row->table->schema, column_name);
+ datum = get_datum(row, column_name, OVSDB_TYPE_STRING, OVSDB_TYPE_STRING,
+ UINT_MAX);
+ if (!datum) {
+ for (i = 0; i < n; i++) {
+ free(keys[i]);
+ free(values[i]);
+ }
+ return;