+static void
+cmd_remove(struct vsctl_context *ctx)
+{
+ const char *table_name = ctx->argv[1];
+ const char *record_id = ctx->argv[2];
+ const char *column_name = ctx->argv[3];
+ const struct vsctl_table_class *table;
+ const struct ovsdb_idl_column *column;
+ const struct ovsdb_idl_row *row;
+ const struct ovsdb_type *type;
+ struct ovsdb_datum old;
+ int i;
+
+ table = get_table(table_name);
+ row = must_get_row(ctx, table, record_id);
+ die_if_error(get_column(table, column_name, &column));
+
+ type = &column->type;
+ ovsdb_datum_clone(&old, ovsdb_idl_read(row, column), &column->type);
+ for (i = 4; i < ctx->argc; i++) {
+ struct ovsdb_type rm_type;
+ struct ovsdb_datum rm;
+ char *error;
+
+ rm_type = *type;
+ rm_type.n_min = 1;
+ rm_type.n_max = UINT_MAX;
+ error = ovsdb_datum_from_string(&rm, &rm_type,
+ ctx->argv[i], ctx->symtab);
+ if (error && ovsdb_type_is_map(&rm_type)) {
+ free(error);
+ rm_type.value.type = OVSDB_TYPE_VOID;
+ die_if_error(ovsdb_datum_from_string(&rm, &rm_type,
+ ctx->argv[i], ctx->symtab));
+ }
+ ovsdb_datum_subtract(&old, type, &rm, &rm_type);
+ ovsdb_datum_destroy(&rm, &rm_type);
+ }
+ if (old.n < type->n_min) {
+ vsctl_fatal("\"remove\" operation would put %u %s in column %s of "
+ "table %s but the minimum number is %u",
+ old.n,
+ type->value.type == OVSDB_TYPE_VOID ? "values" : "pairs",
+ column->name, table->class->name, type->n_min);
+ }
+ ovsdb_idl_txn_verify(row, column);
+ ovsdb_idl_txn_write(row, column, &old);
+}
+
+static void
+pre_cmd_clear(struct vsctl_context *ctx)
+{
+ const char *table_name = ctx->argv[1];
+ const struct vsctl_table_class *table;
+ int i;
+
+ table = pre_get_table(ctx, table_name);
+ for (i = 3; i < ctx->argc; i++) {
+ const struct ovsdb_idl_column *column;
+
+ pre_get_column(ctx, table, ctx->argv[i], &column);
+ }
+}
+
+static void
+cmd_clear(struct vsctl_context *ctx)
+{
+ const char *table_name = ctx->argv[1];
+ const char *record_id = ctx->argv[2];
+ const struct vsctl_table_class *table;
+ const struct ovsdb_idl_row *row;
+ int i;
+
+ table = get_table(table_name);
+ row = must_get_row(ctx, table, record_id);
+ for (i = 3; i < ctx->argc; i++) {
+ const struct ovsdb_idl_column *column;
+ const struct ovsdb_type *type;
+ struct ovsdb_datum datum;
+
+ die_if_error(get_column(table, ctx->argv[i], &column));
+
+ type = &column->type;
+ if (type->n_min > 0) {
+ vsctl_fatal("\"clear\" operation cannot be applied to column %s "
+ "of table %s, which is not allowed to be empty",
+ column->name, table->class->name);
+ }
+
+ ovsdb_datum_init_empty(&datum);
+ ovsdb_idl_txn_write(row, column, &datum);
+ }
+}
+
+static void
+pre_create(struct vsctl_context *ctx)
+{
+ const char *id = shash_find_data(&ctx->options, "--id");
+ const char *table_name = ctx->argv[1];
+ const struct vsctl_table_class *table;
+
+ table = get_table(table_name);
+ if (!id && !table->class->is_root) {
+ VLOG_WARN("applying \"create\" command to table %s without --id "
+ "option will have no effect", table->class->name);
+ }
+}
+
+static void
+cmd_create(struct vsctl_context *ctx)
+{
+ const char *id = shash_find_data(&ctx->options, "--id");
+ const char *table_name = ctx->argv[1];
+ const struct vsctl_table_class *table = get_table(table_name);
+ const struct ovsdb_idl_row *row;
+ const struct uuid *uuid;
+ int i;
+
+ if (id) {
+ struct ovsdb_symbol *symbol = create_symbol(ctx->symtab, id, NULL);
+ if (table->class->is_root) {
+ /* This table is in the root set, meaning that rows created in it
+ * won't disappear even if they are unreferenced, so disable
+ * warnings about that by pretending that there is a reference. */
+ symbol->strong_ref = true;
+ }
+ uuid = &symbol->uuid;
+ } else {
+ uuid = NULL;
+ }
+
+ row = ovsdb_idl_txn_insert(ctx->txn, table->class, uuid);
+ for (i = 2; i < ctx->argc; i++) {
+ set_column(table, row, ctx->argv[i], ctx->symtab);
+ }
+ ds_put_format(&ctx->output, UUID_FMT, UUID_ARGS(&row->uuid));
+}
+
+/* This function may be used as the 'postprocess' function for commands that
+ * insert new rows into the database. It expects that the command's 'run'
+ * function prints the UUID reported by ovsdb_idl_txn_insert() as the command's
+ * sole output. It replaces that output by the row's permanent UUID assigned
+ * by the database server and appends a new-line.
+ *
+ * Currently we use this only for "create", because the higher-level commands
+ * are supposed to be independent of the actual structure of the vswitch
+ * configuration. */
+static void
+post_create(struct vsctl_context *ctx)
+{
+ const struct uuid *real;
+ struct uuid dummy;
+
+ if (!uuid_from_string(&dummy, ds_cstr(&ctx->output))) {
+ NOT_REACHED();
+ }
+ real = ovsdb_idl_txn_get_insert_uuid(ctx->txn, &dummy);
+ if (real) {
+ ds_clear(&ctx->output);
+ ds_put_format(&ctx->output, UUID_FMT, UUID_ARGS(real));
+ }
+ ds_put_char(&ctx->output, '\n');
+}
+
+static void
+pre_cmd_destroy(struct vsctl_context *ctx)
+{
+ const char *table_name = ctx->argv[1];
+
+ pre_get_table(ctx, table_name);
+}
+
+static void
+cmd_destroy(struct vsctl_context *ctx)
+{
+ bool must_exist = !shash_find(&ctx->options, "--if-exists");
+ const char *table_name = ctx->argv[1];
+ const struct vsctl_table_class *table;
+ int i;
+
+ table = get_table(table_name);
+ for (i = 2; i < ctx->argc; i++) {
+ const struct ovsdb_idl_row *row;
+
+ row = (must_exist ? must_get_row : get_row)(ctx, table, ctx->argv[i]);
+ if (row) {
+ ovsdb_idl_txn_delete(row);
+ }
+ }
+}
+
+static bool
+is_condition_satisfied(const struct vsctl_table_class *table,
+ const struct ovsdb_idl_row *row, const char *arg,
+ struct ovsdb_symbol_table *symtab)
+{
+ static const char *operators[] = {
+ "=", "!=", "<", ">", "<=", ">="
+ };
+
+ const struct ovsdb_idl_column *column;
+ const struct ovsdb_datum *have_datum;
+ char *key_string, *value_string;
+ const char *operator;
+ unsigned int idx;
+ char *error;
+ int cmp = 0;
+
+ error = parse_column_key_value(arg, table, &column, &key_string,
+ &operator, operators, ARRAY_SIZE(operators),
+ &value_string);
+ die_if_error(error);
+ if (!value_string) {
+ vsctl_fatal("%s: missing value", arg);
+ }
+
+ have_datum = ovsdb_idl_read(row, column);
+ if (key_string) {
+ union ovsdb_atom want_key, want_value;
+
+ if (column->type.value.type == OVSDB_TYPE_VOID) {
+ vsctl_fatal("cannot specify key to check for non-map column %s",
+ column->name);
+ }
+
+ die_if_error(ovsdb_atom_from_string(&want_key, &column->type.key,
+ key_string, symtab));
+ die_if_error(ovsdb_atom_from_string(&want_value, &column->type.value,
+ value_string, symtab));
+
+ idx = ovsdb_datum_find_key(have_datum,
+ &want_key, column->type.key.type);
+ if (idx != UINT_MAX) {
+ cmp = ovsdb_atom_compare_3way(&have_datum->values[idx],
+ &want_value,
+ column->type.value.type);
+ }
+
+ ovsdb_atom_destroy(&want_key, column->type.key.type);
+ ovsdb_atom_destroy(&want_value, column->type.value.type);
+ } else {
+ struct ovsdb_datum want_datum;
+
+ die_if_error(ovsdb_datum_from_string(&want_datum, &column->type,
+ value_string, symtab));
+ idx = 0;
+ cmp = ovsdb_datum_compare_3way(have_datum, &want_datum,
+ &column->type);
+ ovsdb_datum_destroy(&want_datum, &column->type);
+ }
+
+ free(key_string);
+ free(value_string);
+
+ return (idx == UINT_MAX ? false
+ : !strcmp(operator, "=") ? cmp == 0
+ : !strcmp(operator, "!=") ? cmp != 0
+ : !strcmp(operator, "<") ? cmp < 0
+ : !strcmp(operator, ">") ? cmp > 0
+ : !strcmp(operator, "<=") ? cmp <= 0
+ : !strcmp(operator, ">=") ? cmp >= 0
+ : (abort(), 0));
+}
+
+static void
+pre_cmd_wait_until(struct vsctl_context *ctx)
+{
+ const char *table_name = ctx->argv[1];
+ const struct vsctl_table_class *table;
+ int i;
+
+ table = pre_get_table(ctx, table_name);
+
+ for (i = 3; i < ctx->argc; i++) {
+ pre_parse_column_key_value(ctx, ctx->argv[i], table);
+ }
+}
+
+static void
+cmd_wait_until(struct vsctl_context *ctx)
+{
+ const char *table_name = ctx->argv[1];
+ const char *record_id = ctx->argv[2];
+ const struct vsctl_table_class *table;
+ const struct ovsdb_idl_row *row;
+ int i;
+
+ table = get_table(table_name);
+
+ row = get_row(ctx, table, record_id);
+ if (!row) {
+ ctx->try_again = true;
+ return;
+ }
+
+ for (i = 3; i < ctx->argc; i++) {
+ if (!is_condition_satisfied(table, row, ctx->argv[i], ctx->symtab)) {
+ ctx->try_again = true;
+ return;
+ }
+ }
+}
+\f