ovsdb: Fix result object for "declare" operation.

[ovs.git] / utilities / ovs-vsctl.c

/*
 * Copyright (c) 2009, 2010 Nicira Networks.
 *
 * 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 <assert.h>
#include <ctype.h>
#include <errno.h>
#include <float.h>
#include <getopt.h>
#include <inttypes.h>
#include <regex.h>
#include <signal.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>

#include "command-line.h"
#include "compiler.h"
#include "dirs.h"
#include "dynamic-string.h"
#include "json.h"
#include "ovsdb-data.h"
#include "ovsdb-idl.h"
#include "poll-loop.h"
#include "process.h"
#include "svec.h"
#include "vswitchd/vswitch-idl.h"
#include "timeval.h"
#include "util.h"

#include "vlog.h"
#define THIS_MODULE VLM_vsctl

/* vsctl_fatal() also logs the error, so it is preferred in this file. */
#define ovs_fatal please_use_vsctl_fatal_instead_of_ovs_fatal

struct vsctl_context;

typedef void vsctl_handler_func(struct vsctl_context *);

struct vsctl_command_syntax {
    const char *name;
    int min_args;
    int max_args;
    vsctl_handler_func *run;
    vsctl_handler_func *postprocess;
    const char *options;
};

struct vsctl_command {
    /* Data that remains constant after initialization. */
    const struct vsctl_command_syntax *syntax;
    int argc;
    char **argv;
    struct shash options;

    /* Data modified by commands. */
    struct ds output;
};

/* --db: The database server to contact. */
static const char *db;

/* --oneline: Write each command's output as a single line? */
static bool oneline;

/* --dry-run: Do not commit any changes. */
static bool dry_run;

/* --no-wait: Wait for ovs-vswitchd to reload its configuration? */
static bool wait_for_reload = true;

/* --timeout: Time to wait for a connection to 'db'. */
static int timeout = 5;

/* All supported commands. */
static const struct vsctl_command_syntax all_commands[];

/* The IDL we're using and the current transaction, if any.
 * This is for use by vsctl_exit() only, to allow it to clean up.
 * Other code should use its context arguments. */
static struct ovsdb_idl *the_idl;
static struct ovsdb_idl_txn *the_idl_txn;

static void vsctl_exit(int status) NO_RETURN;
static void vsctl_fatal(const char *, ...) PRINTF_FORMAT(1, 2) NO_RETURN;
static char *default_db(void);
static void usage(void) NO_RETURN;
static void parse_options(int argc, char *argv[]);

static struct vsctl_command *parse_commands(int argc, char *argv[],
                                            size_t *n_commandsp);
static void parse_command(int argc, char *argv[], struct vsctl_command *);
static void do_vsctl(const char *args,
                     struct vsctl_command *, size_t n_commands,
                     struct ovsdb_idl *);

int
main(int argc, char *argv[])
{
    struct ovsdb_idl *idl;
    unsigned int seqno;
    struct vsctl_command *commands;
    size_t n_commands;
    char *args;
    int trials;

    set_program_name(argv[0]);
    signal(SIGPIPE, SIG_IGN);
    time_init();
    vlog_init();
    vlog_set_levels(VLM_ANY_MODULE, VLF_CONSOLE, VLL_WARN);
    vlog_set_levels(VLM_reconnect, VLF_ANY_FACILITY, VLL_WARN);

    /* Log our arguments.  This is often valuable for debugging systems. */
    args = process_escape_args(argv);
    VLOG_INFO("Called as %s", args);

    /* Parse command line. */
    parse_options(argc, argv);
    commands = parse_commands(argc - optind, argv + optind, &n_commands);

    if (timeout) {
        time_alarm(timeout);
    }

    /* Do basic command syntax checking. */

    /* Now execute the commands. */
    idl = the_idl = ovsdb_idl_create(db, &ovsrec_idl_class);
    seqno = ovsdb_idl_get_seqno(idl);
    trials = 0;
    for (;;) {
        unsigned int new_seqno;

        ovsdb_idl_run(idl);
        new_seqno = ovsdb_idl_get_seqno(idl);
        if (new_seqno != seqno) {
            if (++trials > 5) {
                vsctl_fatal("too many database inconsistency failures");
            }
            do_vsctl(args, commands, n_commands, idl);
            seqno = new_seqno;
        }

        ovsdb_idl_wait(idl);
        poll_block();
    }
}

static void
parse_options(int argc, char *argv[])
{
    enum {
        OPT_DB = UCHAR_MAX + 1,
        OPT_ONELINE,
        OPT_NO_SYSLOG,
        OPT_NO_WAIT,
        OPT_DRY_RUN,
        VLOG_OPTION_ENUMS
    };
    static struct option long_options[] = {
        {"db", required_argument, 0, OPT_DB},
        {"no-syslog", no_argument, 0, OPT_NO_SYSLOG},
        {"no-wait", no_argument, 0, OPT_NO_WAIT},
        {"dry-run", no_argument, 0, OPT_DRY_RUN},
        {"oneline", no_argument, 0, OPT_ONELINE},
        {"timeout", required_argument, 0, 't'},
        {"help", no_argument, 0, 'h'},
        {"version", no_argument, 0, 'V'},
        VLOG_LONG_OPTIONS,
        {0, 0, 0, 0},
    };


    for (;;) {
        int c;

        c = getopt_long(argc, argv, "+v::hVt:", long_options, NULL);
        if (c == -1) {
            break;
        }

        switch (c) {
        case OPT_DB:
            db = optarg;
            break;

        case OPT_ONELINE:
            oneline = true;
            break;

        case OPT_NO_SYSLOG:
            vlog_set_levels(VLM_vsctl, VLF_SYSLOG, VLL_WARN);
            break;

        case OPT_NO_WAIT:
            wait_for_reload = false;
            break;

        case OPT_DRY_RUN:
            dry_run = true;
            break;

        case 'h':
            usage();

        case 'V':
            OVS_PRINT_VERSION(0, 0);
            exit(EXIT_SUCCESS);

        case 't':
            timeout = strtoul(optarg, NULL, 10);
            if (timeout < 0) {
                vsctl_fatal("value %s on -t or --timeout is invalid",
                            optarg);
            }
            break;

        VLOG_OPTION_HANDLERS

        case '?':
            exit(EXIT_FAILURE);

        default:
            abort();
        }
    }

    if (!db) {
        db = default_db();
    }
}

static struct vsctl_command *
parse_commands(int argc, char *argv[], size_t *n_commandsp)
{
    struct vsctl_command *commands;
    size_t n_commands, allocated_commands;
    int i, start;

    commands = NULL;
    n_commands = allocated_commands = 0;

    for (start = i = 0; i <= argc; i++) {
        if (i == argc || !strcmp(argv[i], "--")) {
            if (i > start) {
                if (n_commands >= allocated_commands) {
                    struct vsctl_command *c;

                    commands = x2nrealloc(commands, &allocated_commands,
                                          sizeof *commands);
                    for (c = commands; c < &commands[n_commands]; c++) {
                        shash_moved(&c->options);
                    }
                }
                parse_command(i - start, &argv[start],
                              &commands[n_commands++]);
            }
            start = i + 1;
        }
    }
    if (!n_commands) {
        vsctl_fatal("missing command name (use --help for help)");
    }
    *n_commandsp = n_commands;
    return commands;
}

static void
parse_command(int argc, char *argv[], struct vsctl_command *command)
{
    const struct vsctl_command_syntax *p;
    int i;

    shash_init(&command->options);
    for (i = 0; i < argc; i++) {
        if (argv[i][0] != '-') {
            break;
        }
        if (!shash_add_once(&command->options, argv[i], NULL)) {
            vsctl_fatal("'%s' option specified multiple times", argv[i]);
        }
    }
    if (i == argc) {
        vsctl_fatal("missing command name");
    }

    for (p = all_commands; p->name; p++) {
        if (!strcmp(p->name, argv[i])) {
            struct shash_node *node;
            int n_arg;

            SHASH_FOR_EACH (node, &command->options) {
                const char *s = strstr(p->options, node->name);
                int end = s ? s[strlen(node->name)] : EOF;
                if (end != ',' && end != ' ' && end != '\0') {
                    vsctl_fatal("'%s' command has no '%s' option",
                                argv[i], node->name);
                }
            }

            n_arg = argc - i - 1;
            if (n_arg < p->min_args) {
                vsctl_fatal("'%s' command requires at least %d arguments",
                            p->name, p->min_args);
            } else if (n_arg > p->max_args) {
                vsctl_fatal("'%s' command takes at most %d arguments",
                            p->name, p->max_args);
            } else {
                command->syntax = p;
                command->argc = n_arg + 1;
                command->argv = &argv[i];
                return;
            }
        }
    }

    vsctl_fatal("unknown command '%s'; use --help for help", argv[i]);
}

static void
vsctl_fatal(const char *format, ...)
{
    char *message;
    va_list args;

    va_start(args, format);
    message = xvasprintf(format, args);
    va_end(args);

    vlog_set_levels(VLM_vsctl, VLF_CONSOLE, VLL_EMER);
    VLOG_ERR("%s", message);
    ovs_error(0, "%s", message);
    vsctl_exit(EXIT_FAILURE);
}

/* Frees the current transaction and the underlying IDL and then calls
 * exit(status).
 *
 * Freeing the transaction and the IDL is not strictly necessary, but it makes
 * for a clean memory leak report from valgrind in the normal case.  That makes
 * it easier to notice real memory leaks. */
static void
vsctl_exit(int status)
{
    if (the_idl_txn) {
        ovsdb_idl_txn_abort(the_idl_txn);
        ovsdb_idl_txn_destroy(the_idl_txn);
    }
    ovsdb_idl_destroy(the_idl);
    exit(status);
}

static void
usage(void)
{
    printf("\
%s: ovs-vswitchd management utility\n\
usage: %s [OPTIONS] COMMAND [ARG...]\n\
\n\
Bridge commands:\n\
  add-br BRIDGE               create a new bridge named BRIDGE\n\
  add-br BRIDGE PARENT VLAN   create new fake BRIDGE in PARENT on VLAN\n\
  del-br BRIDGE               delete BRIDGE and all of its ports\n\
  list-br                     print the names of all the bridges\n\
  br-exists BRIDGE            test whether BRIDGE exists\n\
  br-to-vlan BRIDGE           print the VLAN which BRIDGE is on\n\
  br-to-parent BRIDGE         print the parent of BRIDGE\n\
  br-set-external-id BRIDGE KEY VALUE  set KEY on BRIDGE to VALUE\n\
  br-set-external-id BRIDGE KEY  unset KEY on BRIDGE\n\
  br-get-external-id BRIDGE KEY  print value of KEY on BRIDGE\n\
  br-get-external-id BRIDGE  list key-value pairs on BRIDGE\n\
\n\
Port commands:\n\
  list-ports BRIDGE           print the names of all the ports on BRIDGE\n\
  add-port BRIDGE PORT        add network device PORT to BRIDGE\n\
  add-bond BRIDGE PORT IFACE...  add bonded port PORT in BRIDGE from IFACES\n\
  del-port [BRIDGE] PORT      delete PORT (which may be bonded) from BRIDGE\n\
  port-to-br PORT             print name of bridge that contains PORT\n\
A bond is considered to be a single port.\n\
\n\
Interface commands (a bond consists of multiple interfaces):\n\
  list-ifaces BRIDGE          print the names of all interfaces on BRIDGE\n\
  iface-to-br IFACE           print name of bridge that contains IFACE\n\
\n\
Controller commands:\n\
  get-controller [BRIDGE]     print the controller for BRIDGE\n\
  del-controller [BRIDGE]     delete the controller for BRIDGE\n\
  set-controller [BRIDGE] TARGET  set the controller for BRIDGE to TARGET\n\
  get-fail-mode [BRIDGE]      print the fail-mode for BRIDGE\n\
  del-fail-mode [BRIDGE]      delete the fail-mode for BRIDGE\n\
  set-fail-mode [BRIDGE] MODE set the fail-mode for BRIDGE to MODE\n\
\n\
SSL commands:\n\
  get-ssl                     print the SSL configuration\n\
  del-ssl                     delete the SSL configuration\n\
  set-ssl PRIV-KEY CERT CA-CERT  set the SSL configuration\n\
\n\
Database commands:\n\
  list TBL [REC]              list RECord (or all records) in TBL\n\
  get TBL REC COL[:KEY]       print values of COLumns in RECORD in TBL\n\
  set TBL REC COL[:KEY]=VALUE set COLumn values in RECord in TBL\n\
  add TBL REC COL [KEY=]VALUE add (KEY=)VALUE to COLumn in RECord in TBL\n\
  remove TBL REC COL [KEY=]VALUE  remove (KEY=)VALUE from COLumn\n\
  clear TBL REC COL           clear values from COLumn in RECord in TBL\n\
  create TBL COL[:KEY]=VALUE  create and initialize new record\n\
  destroy TBL REC             delete REC from TBL\n\
Potentially unsafe database commands require --force option.\n\
\n\
Options:\n\
  --db=DATABASE               connect to DATABASE\n\
                              (default: %s)\n\
  --oneline                   print exactly one line of output per command\n",
           program_name, program_name, default_db());
    vlog_usage();
    printf("\n\
Other options:\n\
  -h, --help                  display this help message\n\
  -V, --version               display version information\n");
    exit(EXIT_SUCCESS);
}

static char *
default_db(void)
{
    static char *def;
    if (!def) {
        def = xasprintf("unix:%s/ovsdb-server", ovs_rundir);
    }
    return def;
}
\f
struct vsctl_context {
    /* Read-only. */
    int argc;
    char **argv;
    struct shash options;

    /* Modifiable state. */
    struct ds output;
    struct ovsdb_idl *idl;
    struct ovsdb_idl_txn *txn;
    const struct ovsrec_open_vswitch *ovs;
};

struct vsctl_bridge {
    struct ovsrec_bridge *br_cfg;
    char *name;
    struct ovsrec_controller *ctrl;
    struct vsctl_bridge *parent;
    int vlan;
};

struct vsctl_port {
    struct ovsrec_port *port_cfg;
    struct vsctl_bridge *bridge;
};

struct vsctl_iface {
    struct ovsrec_interface *iface_cfg;
    struct vsctl_port *port;
};

struct vsctl_info {
    struct shash bridges;
    struct shash ports;
    struct shash ifaces;
    struct ovsrec_controller *ctrl;
};

static struct vsctl_bridge *
add_bridge(struct vsctl_info *b,
           struct ovsrec_bridge *br_cfg, const char *name,
           struct vsctl_bridge *parent, int vlan)
{
    struct vsctl_bridge *br = xmalloc(sizeof *br);
    br->br_cfg = br_cfg;
    br->name = xstrdup(name);
    br->parent = parent;
    br->vlan = vlan;
    br->ctrl = parent ? parent->br_cfg->controller : br_cfg->controller;
    shash_add(&b->bridges, br->name, br);
    return br;
}

static bool
port_is_fake_bridge(const struct ovsrec_port *port_cfg)
{
    return (port_cfg->fake_bridge
            && port_cfg->tag
            && *port_cfg->tag >= 1 && *port_cfg->tag <= 4095);
}

static struct vsctl_bridge *
find_vlan_bridge(struct vsctl_info *info,
                 struct vsctl_bridge *parent, int vlan)
{
    struct shash_node *node;

    SHASH_FOR_EACH (node, &info->bridges) {
        struct vsctl_bridge *br = node->data;
        if (br->parent == parent && br->vlan == vlan) {
            return br;
        }
    }

    return NULL;
}

static void
free_info(struct vsctl_info *info)
{
    struct shash_node *node;

    SHASH_FOR_EACH (node, &info->bridges) {
        struct vsctl_bridge *bridge = node->data;
        free(bridge->name);
        free(bridge);
    }
    shash_destroy(&info->bridges);

    SHASH_FOR_EACH (node, &info->ports) {
        struct vsctl_port *port = node->data;
        free(port);
    }
    shash_destroy(&info->ports);

    SHASH_FOR_EACH (node, &info->ifaces) {
        struct vsctl_iface *iface = node->data;
        free(iface);
    }
    shash_destroy(&info->ifaces);
}

static void
get_info(const struct ovsrec_open_vswitch *ovs, struct vsctl_info *info)
{
    struct shash bridges, ports;
    size_t i;

    shash_init(&info->bridges);
    shash_init(&info->ports);
    shash_init(&info->ifaces);

    info->ctrl = ovs->controller;

    shash_init(&bridges);
    shash_init(&ports);
    for (i = 0; i < ovs->n_bridges; i++) {
        struct ovsrec_bridge *br_cfg = ovs->bridges[i];
        struct vsctl_bridge *br;
        size_t j;

        if (!shash_add_once(&bridges, br_cfg->name, NULL)) {
            VLOG_WARN("%s: database contains duplicate bridge name",
                      br_cfg->name);
            continue;
        }
        br = add_bridge(info, br_cfg, br_cfg->name, NULL, 0);
        if (!br) {
            continue;
        }

        for (j = 0; j < br_cfg->n_ports; j++) {
            struct ovsrec_port *port_cfg = br_cfg->ports[j];

            if (!shash_add_once(&ports, port_cfg->name, NULL)) {
                VLOG_WARN("%s: database contains duplicate port name",
                          port_cfg->name);
                continue;
            }

            if (port_is_fake_bridge(port_cfg)
                && shash_add_once(&bridges, port_cfg->name, NULL)) {
                add_bridge(info, NULL, port_cfg->name, br, *port_cfg->tag);
            }
        }
    }
    shash_destroy(&bridges);
    shash_destroy(&ports);

    shash_init(&bridges);
    shash_init(&ports);
    for (i = 0; i < ovs->n_bridges; i++) {
        struct ovsrec_bridge *br_cfg = ovs->bridges[i];
        struct vsctl_bridge *br;
        size_t j;

        if (!shash_add_once(&bridges, br_cfg->name, NULL)) {
            continue;
        }
        br = shash_find_data(&info->bridges, br_cfg->name);
        for (j = 0; j < br_cfg->n_ports; j++) {
            struct ovsrec_port *port_cfg = br_cfg->ports[j];
            struct vsctl_port *port;
            size_t k;

            if (!shash_add_once(&ports, port_cfg->name, NULL)) {
                continue;
            }

            if (port_is_fake_bridge(port_cfg)
                && !shash_add_once(&bridges, port_cfg->name, NULL)) {
                continue;
            }

            port = xmalloc(sizeof *port);
            port->port_cfg = port_cfg;
            if (port_cfg->tag
                && *port_cfg->tag >= 1 && *port_cfg->tag <= 4095) {
                port->bridge = find_vlan_bridge(info, br, *port_cfg->tag);
                if (!port->bridge) {
                    port->bridge = br;
                }
            } else {
                port->bridge = br;
            }
            shash_add(&info->ports, port_cfg->name, port);

            for (k = 0; k < port_cfg->n_interfaces; k++) {
                struct ovsrec_interface *iface_cfg = port_cfg->interfaces[k];
                struct vsctl_iface *iface;

                if (shash_find(&info->ifaces, iface_cfg->name)) {
                    VLOG_WARN("%s: database contains duplicate interface name",
                              iface_cfg->name);
                    continue;
                }

                iface = xmalloc(sizeof *iface);
                iface->iface_cfg = iface_cfg;
                iface->port = port;
                shash_add(&info->ifaces, iface_cfg->name, iface);
            }
        }
    }
    shash_destroy(&bridges);
    shash_destroy(&ports);
}

static void
check_conflicts(struct vsctl_info *info, const char *name,
                char *msg)
{
    struct vsctl_iface *iface;
    struct vsctl_port *port;

    if (shash_find(&info->bridges, name)) {
        vsctl_fatal("%s because a bridge named %s already exists",
                    msg, name);
    }

    port = shash_find_data(&info->ports, name);
    if (port) {
        vsctl_fatal("%s because a port named %s already exists on "
                    "bridge %s", msg, name, port->bridge->name);
    }

    iface = shash_find_data(&info->ifaces, name);
    if (iface) {
        vsctl_fatal("%s because an interface named %s already exists "
                    "on bridge %s", msg, name, iface->port->bridge->name);
    }

    free(msg);
}

static struct vsctl_bridge *
find_bridge(struct vsctl_info *info, const char *name, bool must_exist)
{
    struct vsctl_bridge *br = shash_find_data(&info->bridges, name);
    if (must_exist && !br) {
        vsctl_fatal("no bridge named %s", name);
    }
    return br;
}

static struct vsctl_bridge *
find_real_bridge(struct vsctl_info *info, const char *name, bool must_exist)
{
    struct vsctl_bridge *br = find_bridge(info, name, must_exist);
    if (br && br->parent) {
        vsctl_fatal("%s is a fake bridge", name);
    }
    return br;
}

static struct vsctl_port *
find_port(struct vsctl_info *info, const char *name, bool must_exist)
{
    struct vsctl_port *port = shash_find_data(&info->ports, name);
    if (port && !strcmp(name, port->bridge->name)) {
        port = NULL;
    }
    if (must_exist && !port) {
        vsctl_fatal("no port named %s", name);
    }
    return port;
}

static struct vsctl_iface *
find_iface(struct vsctl_info *info, const char *name, bool must_exist)
{
    struct vsctl_iface *iface = shash_find_data(&info->ifaces, name);
    if (iface && !strcmp(name, iface->port->bridge->name)) {
        iface = NULL;
    }
    if (must_exist && !iface) {
        vsctl_fatal("no interface named %s", name);
    }
    return iface;
}

static void
bridge_insert_port(struct ovsrec_bridge *br, struct ovsrec_port *port)
{
    struct ovsrec_port **ports;
    size_t i;

    ports = xmalloc(sizeof *br->ports * (br->n_ports + 1));
    for (i = 0; i < br->n_ports; i++) {
        ports[i] = br->ports[i];
    }
    ports[br->n_ports] = port;
    ovsrec_bridge_set_ports(br, ports, br->n_ports + 1);
    free(ports);
}

static void
bridge_delete_port(struct ovsrec_bridge *br, struct ovsrec_port *port)
{
    struct ovsrec_port **ports;
    size_t i, n;

    ports = xmalloc(sizeof *br->ports * br->n_ports);
    for (i = n = 0; i < br->n_ports; i++) {
        if (br->ports[i] != port) {
            ports[n++] = br->ports[i];
        }
    }
    ovsrec_bridge_set_ports(br, ports, n);
    free(ports);
}

static void
ovs_insert_bridge(const struct ovsrec_open_vswitch *ovs,
                  struct ovsrec_bridge *bridge)
{
    struct ovsrec_bridge **bridges;
    size_t i;

    bridges = xmalloc(sizeof *ovs->bridges * (ovs->n_bridges + 1));
    for (i = 0; i < ovs->n_bridges; i++) {
        bridges[i] = ovs->bridges[i];
    }
    bridges[ovs->n_bridges] = bridge;
    ovsrec_open_vswitch_set_bridges(ovs, bridges, ovs->n_bridges + 1);
    free(bridges);
}

static void
ovs_delete_bridge(const struct ovsrec_open_vswitch *ovs,
                  struct ovsrec_bridge *bridge)
{
    struct ovsrec_bridge **bridges;
    size_t i, n;

    bridges = xmalloc(sizeof *ovs->bridges * ovs->n_bridges);
    for (i = n = 0; i < ovs->n_bridges; i++) {
        if (ovs->bridges[i] != bridge) {
            bridges[n++] = ovs->bridges[i];
        }
    }
    ovsrec_open_vswitch_set_bridges(ovs, bridges, n);
    free(bridges);
}

static void
cmd_init(struct vsctl_context *ctx UNUSED)
{
}

static void
cmd_add_br(struct vsctl_context *ctx)
{
    const char *br_name = ctx->argv[1];
    struct vsctl_info info;

    get_info(ctx->ovs, &info);
    check_conflicts(&info, br_name,
                    xasprintf("cannot create a bridge named %s", br_name));

    if (ctx->argc == 2) {
        struct ovsrec_bridge *br;
        struct ovsrec_port *port;
        struct ovsrec_interface *iface;

        iface = ovsrec_interface_insert(ctx->txn);
        ovsrec_interface_set_name(iface, br_name);

        port = ovsrec_port_insert(ctx->txn);
        ovsrec_port_set_name(port, br_name);
        ovsrec_port_set_interfaces(port, &iface, 1);

        br = ovsrec_bridge_insert(ctx->txn);
        ovsrec_bridge_set_name(br, br_name);
        ovsrec_bridge_set_ports(br, &port, 1);

        ovs_insert_bridge(ctx->ovs, br);
    } else if (ctx->argc == 3) {
        vsctl_fatal("'%s' command takes exactly 1 or 3 arguments",
                    ctx->argv[0]);
    } else if (ctx->argc == 4) {
        const char *parent_name = ctx->argv[2];
        int vlan = atoi(ctx->argv[3]);
        struct ovsrec_bridge *br;
        struct vsctl_bridge *parent;
        struct ovsrec_port *port;
        struct ovsrec_interface *iface;
        int64_t tag = vlan;

        if (vlan < 1 || vlan > 4095) {
            vsctl_fatal("%s: vlan must be between 1 and 4095", ctx->argv[0]);
        }

        parent = find_bridge(&info, parent_name, false);
        if (parent && parent->vlan) {
            vsctl_fatal("cannot create bridge with fake bridge as parent");
        }
        if (!parent) {
            vsctl_fatal("parent bridge %s does not exist", parent_name);
        }
        br = parent->br_cfg;

        iface = ovsrec_interface_insert(ctx->txn);
        ovsrec_interface_set_name(iface, br_name);
        ovsrec_interface_set_type(iface, "internal");

        port = ovsrec_port_insert(ctx->txn);
        ovsrec_port_set_name(port, br_name);
        ovsrec_port_set_interfaces(port, &iface, 1);
        ovsrec_port_set_fake_bridge(port, true);
        ovsrec_port_set_tag(port, &tag, 1);

        bridge_insert_port(br, port);
    } else {
        NOT_REACHED();
    }

    free_info(&info);
}

static void
del_port(struct vsctl_info *info, struct vsctl_port *port)
{
    struct shash_node *node;

    SHASH_FOR_EACH (node, &info->ifaces) {
        struct vsctl_iface *iface = node->data;
        if (iface->port == port) {
            ovsrec_interface_delete(iface->iface_cfg);
        }
    }
    ovsrec_port_delete(port->port_cfg);

    bridge_delete_port((port->bridge->parent
                        ? port->bridge->parent->br_cfg
                        : port->bridge->br_cfg), port->port_cfg);
}

static void
cmd_del_br(struct vsctl_context *ctx)
{
    bool must_exist = !shash_find(&ctx->options, "--if-exists");
    struct vsctl_bridge *bridge;
    struct vsctl_info info;

    get_info(ctx->ovs, &info);
    bridge = find_bridge(&info, ctx->argv[1], must_exist);
    if (bridge) {
        struct shash_node *node;

        SHASH_FOR_EACH (node, &info.ports) {
            struct vsctl_port *port = node->data;
            if (port->bridge == bridge
                || !strcmp(port->port_cfg->name, bridge->name)) {
                del_port(&info, port);
            }
        }
        if (bridge->br_cfg) {
            ovsrec_bridge_delete(bridge->br_cfg);
            ovs_delete_bridge(ctx->ovs, bridge->br_cfg);
        }
    }
    free_info(&info);
}

static void
output_sorted(struct svec *svec, struct ds *output)
{
    const char *name;
    size_t i;

    svec_sort(svec);
    SVEC_FOR_EACH (i, name, svec) {
        ds_put_format(output, "%s\n", name);
    }
}

static void
cmd_list_br(struct vsctl_context *ctx)
{
    struct shash_node *node;
    struct vsctl_info info;
    struct svec bridges;

    get_info(ctx->ovs, &info);

    svec_init(&bridges);
    SHASH_FOR_EACH (node, &info.bridges) {
        struct vsctl_bridge *br = node->data;
        svec_add(&bridges, br->name);
    }
    output_sorted(&bridges, &ctx->output);
    svec_destroy(&bridges);

    free_info(&info);
}

static void
cmd_br_exists(struct vsctl_context *ctx)
{
    struct vsctl_info info;

    get_info(ctx->ovs, &info);
    if (!find_bridge(&info, ctx->argv[1], false)) {
        vsctl_exit(2);
    }
    free_info(&info);
}

/* Returns true if 'b_prefix' (of length 'b_prefix_len') concatenated with 'b'
 * equals 'a', false otherwise. */
static bool
key_matches(const char *a,
            const char *b_prefix, size_t b_prefix_len, const char *b)
{
    return !strncmp(a, b_prefix, b_prefix_len) && !strcmp(a + b_prefix_len, b);
}

static void
set_external_id(char **old_keys, char **old_values, size_t old_n,
                char *key, char *value,
                char ***new_keysp, char ***new_valuesp, size_t *new_np)
{
    char **new_keys;
    char **new_values;
    size_t new_n;
    size_t i;

    new_keys = xmalloc(sizeof *new_keys * (old_n + 1));
    new_values = xmalloc(sizeof *new_values * (old_n + 1));
    new_n = 0;
    for (i = 0; i < old_n; i++) {
        if (strcmp(key, old_keys[i])) {
            new_keys[new_n] = old_keys[i];
            new_values[new_n] = old_values[i];
            new_n++;
        }
    }
    if (value) {
        new_keys[new_n] = key;
        new_values[new_n] = value;
        new_n++;
    }
    *new_keysp = new_keys;
    *new_valuesp = new_values;
    *new_np = new_n;
}

static void
cmd_br_set_external_id(struct vsctl_context *ctx)
{
    struct vsctl_info info;
    struct vsctl_bridge *bridge;
    char **keys, **values;
    size_t n;

    get_info(ctx->ovs, &info);
    bridge = find_bridge(&info, ctx->argv[1], true);
    if (bridge->br_cfg) {
        set_external_id(bridge->br_cfg->key_external_ids,
                        bridge->br_cfg->value_external_ids,
                        bridge->br_cfg->n_external_ids,
                        ctx->argv[2], ctx->argc >= 4 ? ctx->argv[3] : NULL,
                        &keys, &values, &n);
        ovsrec_bridge_set_external_ids(bridge->br_cfg, keys, values, n);
    } else {
        char *key = xasprintf("fake-bridge-%s", ctx->argv[2]);
        struct vsctl_port *port = shash_find_data(&info.ports, ctx->argv[1]);
        set_external_id(port->port_cfg->key_external_ids,
                        port->port_cfg->value_external_ids,
                        port->port_cfg->n_external_ids,
                        key, ctx->argc >= 4 ? ctx->argv[3] : NULL,
                        &keys, &values, &n);
        ovsrec_port_set_external_ids(port->port_cfg, keys, values, n);
        free(key);
    }
    free(keys);
    free(values);

    free_info(&info);
}

static void
get_external_id(char **keys, char **values, size_t n,
                const char *prefix, const char *key,
                struct ds *output)
{
    size_t prefix_len = strlen(prefix);
    struct svec svec;
    size_t i;

    svec_init(&svec);
    for (i = 0; i < n; i++) {
        if (!key && !strncmp(keys[i], prefix, prefix_len)) {
            svec_add_nocopy(&svec, xasprintf("%s=%s",
                                             keys[i] + prefix_len, values[i]));
        } else if (key_matches(keys[i], prefix, prefix_len, key)) {
            svec_add(&svec, values[i]);
            break;
        }
    }
    output_sorted(&svec, output);
    svec_destroy(&svec);
}

static void
cmd_br_get_external_id(struct vsctl_context *ctx)
{
    struct vsctl_info info;
    struct vsctl_bridge *bridge;

    get_info(ctx->ovs, &info);
    bridge = find_bridge(&info, ctx->argv[1], true);
    if (bridge->br_cfg) {
        get_external_id(bridge->br_cfg->key_external_ids,
                        bridge->br_cfg->value_external_ids,
                        bridge->br_cfg->n_external_ids,
                        "", ctx->argc >= 3 ? ctx->argv[2] : NULL,
                        &ctx->output);
    } else {
        struct vsctl_port *port = shash_find_data(&info.ports, ctx->argv[1]);
        get_external_id(port->port_cfg->key_external_ids,
                        port->port_cfg->value_external_ids,
                        port->port_cfg->n_external_ids,
                        "fake-bridge-", ctx->argc >= 3 ? ctx->argv[2] : NULL, &ctx->output);
    }
    free_info(&info);
}


static void
cmd_list_ports(struct vsctl_context *ctx)
{
    struct vsctl_bridge *br;
    struct shash_node *node;
    struct vsctl_info info;
    struct svec ports;

    get_info(ctx->ovs, &info);
    br = find_bridge(&info, ctx->argv[1], true);

    svec_init(&ports);
    SHASH_FOR_EACH (node, &info.ports) {
        struct vsctl_port *port = node->data;

        if (strcmp(port->port_cfg->name, br->name) && br == port->bridge) {
            svec_add(&ports, port->port_cfg->name);
        }
    }
    output_sorted(&ports, &ctx->output);
    svec_destroy(&ports);

    free_info(&info);
}

static void
add_port(struct vsctl_context *ctx,
         const char *br_name, const char *port_name, bool fake_iface,
         char *iface_names[], int n_ifaces)
{
    struct vsctl_info info;
    struct vsctl_bridge *bridge;
    struct ovsrec_interface **ifaces;
    struct ovsrec_port *port;
    size_t i;

    get_info(ctx->ovs, &info);
    check_conflicts(&info, port_name,
                    xasprintf("cannot create a port named %s", port_name));
    /* XXX need to check for conflicts on interfaces too */
    bridge = find_bridge(&info, br_name, true);

    ifaces = xmalloc(n_ifaces * sizeof *ifaces);
    for (i = 0; i < n_ifaces; i++) {
        ifaces[i] = ovsrec_interface_insert(ctx->txn);
        ovsrec_interface_set_name(ifaces[i], iface_names[i]);
    }

    port = ovsrec_port_insert(ctx->txn);
    ovsrec_port_set_name(port, port_name);
    ovsrec_port_set_interfaces(port, ifaces, n_ifaces);
    ovsrec_port_set_bond_fake_iface(port, fake_iface);
    free(ifaces);

    if (bridge->vlan) {
        int64_t tag = bridge->vlan;
        ovsrec_port_set_tag(port, &tag, 1);
    }

    bridge_insert_port((bridge->parent ? bridge->parent->br_cfg
                        : bridge->br_cfg), port);

    free_info(&info);
}

static void
cmd_add_port(struct vsctl_context *ctx)
{
    add_port(ctx, ctx->argv[1], ctx->argv[2], false, &ctx->argv[2], 1);
}

static void
cmd_add_bond(struct vsctl_context *ctx)
{
    bool fake_iface = shash_find(&ctx->options, "--fake-iface");

    add_port(ctx, ctx->argv[1], ctx->argv[2], fake_iface,
             &ctx->argv[3], ctx->argc - 3);
}

static void
cmd_del_port(struct vsctl_context *ctx)
{
    bool must_exist = !shash_find(&ctx->options, "--if-exists");
    struct vsctl_info info;

    get_info(ctx->ovs, &info);
    if (ctx->argc == 2) {
        struct vsctl_port *port = find_port(&info, ctx->argv[1], must_exist);
        if (port) {
            del_port(&info, port);
        }
    } else if (ctx->argc == 3) {
        struct vsctl_bridge *bridge = find_bridge(&info, ctx->argv[1], true);
        struct vsctl_port *port = find_port(&info, ctx->argv[2], must_exist);

        if (port) {
            if (port->bridge == bridge) {
                del_port(&info, port);
            } else if (port->bridge->parent == bridge) {
                vsctl_fatal("bridge %s does not have a port %s (although its "
                            "parent bridge %s does)",
                            ctx->argv[1], ctx->argv[2], bridge->parent->name);
            } else {
                vsctl_fatal("bridge %s does not have a port %s",
                            ctx->argv[1], ctx->argv[2]);
            }
        }
    }
    free_info(&info);
}

static void
cmd_port_to_br(struct vsctl_context *ctx)
{
    struct vsctl_port *port;
    struct vsctl_info info;

    get_info(ctx->ovs, &info);
    port = find_port(&info, ctx->argv[1], true);
    ds_put_format(&ctx->output, "%s\n", port->bridge->name);
    free_info(&info);
}

static void
cmd_br_to_vlan(struct vsctl_context *ctx)
{
    struct vsctl_bridge *bridge;
    struct vsctl_info info;

    get_info(ctx->ovs, &info);
    bridge = find_bridge(&info, ctx->argv[1], true);
    ds_put_format(&ctx->output, "%d\n", bridge->vlan);
    free_info(&info);
}

static void
cmd_br_to_parent(struct vsctl_context *ctx)
{
    struct vsctl_bridge *bridge;
    struct vsctl_info info;

    get_info(ctx->ovs, &info);
    bridge = find_bridge(&info, ctx->argv[1], true);
    if (bridge->parent) {
        bridge = bridge->parent;
    }
    ds_put_format(&ctx->output, "%s\n", bridge->name);
    free_info(&info);
}

static void
cmd_list_ifaces(struct vsctl_context *ctx)
{
    struct vsctl_bridge *br;
    struct shash_node *node;
    struct vsctl_info info;
    struct svec ifaces;

    get_info(ctx->ovs, &info);
    br = find_bridge(&info, ctx->argv[1], true);

    svec_init(&ifaces);
    SHASH_FOR_EACH (node, &info.ifaces) {
        struct vsctl_iface *iface = node->data;

        if (strcmp(iface->iface_cfg->name, br->name)
            && br == iface->port->bridge) {
            svec_add(&ifaces, iface->iface_cfg->name);
        }
    }
    output_sorted(&ifaces, &ctx->output);
    svec_destroy(&ifaces);

    free_info(&info);
}

static void
cmd_iface_to_br(struct vsctl_context *ctx)
{
    struct vsctl_iface *iface;
    struct vsctl_info info;

    get_info(ctx->ovs, &info);
    iface = find_iface(&info, ctx->argv[1], true);
    ds_put_format(&ctx->output, "%s\n", iface->port->bridge->name);
    free_info(&info);
}

static void
cmd_get_controller(struct vsctl_context *ctx)
{
    struct vsctl_info info;

    get_info(ctx->ovs, &info);

    if (ctx->argc == 1) {
        /* Return the controller from the "Open_vSwitch" table */
        if (info.ctrl) {
            ds_put_format(&ctx->output, "%s\n", info.ctrl->target);
        }
    } else {
        /* Return the controller for a particular bridge. */
        struct vsctl_bridge *br = find_bridge(&info, ctx->argv[1], true);

        /* If no controller is explicitly defined for the requested
         * bridge, fallback to the "Open_vSwitch" table's controller. */
        if (br->ctrl) {
            ds_put_format(&ctx->output, "%s\n", br->ctrl->target);
        } else if (info.ctrl) {
            ds_put_format(&ctx->output, "%s\n", info.ctrl->target);
        }
    }

    free_info(&info);
}

static void
cmd_del_controller(struct vsctl_context *ctx)
{
    struct vsctl_info info;

    get_info(ctx->ovs, &info);

    if (ctx->argc == 1) {
        if (info.ctrl) {
            ovsrec_controller_delete(info.ctrl);
            ovsrec_open_vswitch_set_controller(ctx->ovs, NULL);
        }
    } else {
        struct vsctl_bridge *br = find_real_bridge(&info, ctx->argv[1], true);

        if (br->ctrl) {
            ovsrec_controller_delete(br->ctrl);
            ovsrec_bridge_set_controller(br->br_cfg, NULL);
        }
    }

    free_info(&info);
}

static void
cmd_set_controller(struct vsctl_context *ctx)
{
    struct vsctl_info info;
    struct ovsrec_controller *ctrl;

    get_info(ctx->ovs, &info);

    if (ctx->argc == 2) {
        /* Set the controller in the "Open_vSwitch" table. */
        if (info.ctrl) {
            ovsrec_controller_delete(info.ctrl);
        }
        ctrl = ovsrec_controller_insert(ctx->txn);
        ovsrec_controller_set_target(ctrl, ctx->argv[1]);
        ovsrec_open_vswitch_set_controller(ctx->ovs, ctrl);
    } else {
        /* Set the controller for a particular bridge. */
        struct vsctl_bridge *br = find_real_bridge(&info, ctx->argv[1], true);

        if (br->ctrl) {
            ovsrec_controller_delete(br->ctrl);
        }
        ctrl = ovsrec_controller_insert(ctx->txn);
        ovsrec_controller_set_target(ctrl, ctx->argv[2]);
        ovsrec_bridge_set_controller(br->br_cfg, ctrl);
    }

    free_info(&info);
}

static void
cmd_get_fail_mode(struct vsctl_context *ctx)
{
    struct vsctl_info info;
    const char *fail_mode = NULL;

    get_info(ctx->ovs, &info);

    if (ctx->argc == 1) {
        /* Return the fail-mode from the "Open_vSwitch" table */
        if (info.ctrl && info.ctrl->fail_mode) {
            fail_mode = info.ctrl->fail_mode;
        }
    } else {
        /* Return the fail-mode for a particular bridge. */
        struct vsctl_bridge *br = find_bridge(&info, ctx->argv[1], true);

        /* If no controller or fail-mode is explicitly defined for the 
         * requested bridge, fallback to the "Open_vSwitch" table's 
         * setting. */
        if (br->ctrl && br->ctrl->fail_mode) {
            fail_mode = br->ctrl->fail_mode;
        } else if (info.ctrl && info.ctrl->fail_mode) {
            fail_mode = info.ctrl->fail_mode;
        }
    }

    if (fail_mode && strlen(fail_mode)) {
        ds_put_format(&ctx->output, "%s\n", fail_mode);
    }

    free_info(&info);
}

static void
cmd_del_fail_mode(struct vsctl_context *ctx)
{
    struct vsctl_info info;

    get_info(ctx->ovs, &info);

    if (ctx->argc == 1) {
        if (info.ctrl && info.ctrl->fail_mode) {
            ovsrec_controller_set_fail_mode(info.ctrl, NULL);
        }
    } else {
        struct vsctl_bridge *br = find_real_bridge(&info, ctx->argv[1], true);

        if (br->ctrl && br->ctrl->fail_mode) {
            ovsrec_controller_set_fail_mode(br->ctrl, NULL);
        }
    }

    free_info(&info);
}

static void
cmd_set_fail_mode(struct vsctl_context *ctx)
{
    struct vsctl_info info;
    const char *fail_mode;

    get_info(ctx->ovs, &info);

    fail_mode = (ctx->argc == 2) ? ctx->argv[1] : ctx->argv[2];

    if (strcmp(fail_mode, "standalone") && strcmp(fail_mode, "secure")) {
        vsctl_fatal("fail-mode must be \"standalone\" or \"secure\"");
    }

    if (ctx->argc == 2) {
        /* Set the fail-mode in the "Open_vSwitch" table. */
        if (!info.ctrl) {
            vsctl_fatal("no controller declared");
        }
        ovsrec_controller_set_fail_mode(info.ctrl, fail_mode);
    } else {
        struct vsctl_bridge *br = find_real_bridge(&info, ctx->argv[1], true);

        if (!br->ctrl) {
            vsctl_fatal("no controller declared for %s", br->name);
        }
        ovsrec_controller_set_fail_mode(br->ctrl, fail_mode);
    }

    free_info(&info);
}

static void
cmd_get_ssl(struct vsctl_context *ctx)
{
    struct ovsrec_ssl *ssl = ctx->ovs->ssl;

    if (ssl) {
        ds_put_format(&ctx->output, "Private key: %s\n", ssl->private_key);
        ds_put_format(&ctx->output, "Certificate: %s\n", ssl->certificate);
        ds_put_format(&ctx->output, "CA Certificate: %s\n", ssl->ca_cert);
        ds_put_format(&ctx->output, "Bootstrap: %s\n",
                ssl->bootstrap_ca_cert ? "true" : "false");
    }
}

static void
cmd_del_ssl(struct vsctl_context *ctx)
{
    struct ovsrec_ssl *ssl = ctx->ovs->ssl;

    if (ssl) {
        ovsrec_ssl_delete(ssl);
        ovsrec_open_vswitch_set_ssl(ctx->ovs, NULL);
    }
}

static void
cmd_set_ssl(struct vsctl_context *ctx)
{
    bool bootstrap = shash_find(&ctx->options, "--bootstrap");
    struct ovsrec_ssl *ssl = ctx->ovs->ssl;

    if (ssl) {
        ovsrec_ssl_delete(ssl);
    }
    ssl = ovsrec_ssl_insert(ctx->txn);

    ovsrec_ssl_set_private_key(ssl, ctx->argv[1]);
    ovsrec_ssl_set_certificate(ssl, ctx->argv[2]);
    ovsrec_ssl_set_ca_cert(ssl, ctx->argv[3]);

    ovsrec_ssl_set_bootstrap_ca_cert(ssl, bootstrap);

    ovsrec_open_vswitch_set_ssl(ctx->ovs, ssl);
}
\f
/* Parameter commands. */

/* POSIX extended regular expression for an 8-bit unsigned decimal integer. */
#define OCTET_RE "([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])"

/* POSIX extended regular expression for an IP address. */
#define IP_RE "("OCTET_RE"\\."OCTET_RE"\\."OCTET_RE"\\."OCTET_RE")"

/* POSIX extended regular expression for a netmask. */
#define NETMASK_RE                              \
        "255.255.255."NETMASK_END_RE"|"         \
        "255.255."NETMASK_END_RE".0|"           \
        "255."NETMASK_END_RE".0.0|"             \
        NETMASK_END_RE".0.0.0"
#define NETMASK_END_RE "(255|254|252|248|240|224|192|128|0)"

/* POSIX extended regular expression for an Ethernet address. */
#define XX_RE "[0-9a-fA-F][0-9a-fA-F]"
#define MAC_RE XX_RE":"XX_RE":"XX_RE":"XX_RE":"XX_RE":"XX_RE

/* POSIX extended regular expression for a TCP or UDP port number. */
#define PORT_RE                                 \
    "([0-9]|"                                   \
    "[1-9][0-9]|"                               \
    "[1-9][0-9][0-9]|"                          \
    "[1-9][0-9][0-9][0-9]|"                     \
    "[1-5][0-9][0-9][0-9][0-9]|"                \
    "6[1-4][0-9][0-9][0-9]|"                    \
    "65[1-4][0-9][0-9]|"                        \
    "655[1-2][0-9]|"                            \
    "6553[1-5])"

enum {
    VSCF_READONLY = 1 << 0,
    VSCF_HIDDEN = 1 << 1
};

struct vsctl_column {
    struct ovsdb_idl_column *idl;
    int flags;
    const char *constraint;
};

static const struct vsctl_column bridge_columns[] = {
    {&ovsrec_bridge_col_controller, VSCF_READONLY, NULL},
    {&ovsrec_bridge_col_datapath_id, VSCF_READONLY, NULL},
    {&ovsrec_bridge_col_datapath_type, VSCF_READONLY, NULL},
    {&ovsrec_bridge_col_external_ids, 0, NULL},
    {&ovsrec_bridge_col_flood_vlans, 0, "[1,4095]"},
    {&ovsrec_bridge_col_mirrors, VSCF_READONLY, NULL},
    {&ovsrec_bridge_col_name, VSCF_READONLY, NULL},
    {&ovsrec_bridge_col_netflow, VSCF_READONLY, NULL},
    {&ovsrec_bridge_col_other_config, 0, NULL},
    {&ovsrec_bridge_col_ports, VSCF_READONLY, NULL},
    {NULL, 0, NULL},
};

static const struct vsctl_column controller_columns[] = {
    {&ovsrec_controller_col_connection_mode, 0, "in-band|out-of-band"},
    {&ovsrec_controller_col_controller_burst_limit, 0, "[25,]"},
    {&ovsrec_controller_col_controller_rate_limit, 0, "[100,]"},
    {&ovsrec_controller_col_discover_accept_regex, 0, NULL},
    {&ovsrec_controller_col_discover_update_resolv_conf, 0, NULL},
    {&ovsrec_controller_col_fail_mode, 0, "standalone|secure"},
    {&ovsrec_controller_col_inactivity_probe, 0, "[5000,]"},
    {&ovsrec_controller_col_local_gateway, 0, IP_RE},
    {&ovsrec_controller_col_local_ip, 0, IP_RE},
    {&ovsrec_controller_col_local_netmask, 0, NETMASK_RE},
    {&ovsrec_controller_col_max_backoff, 0, "[1000,]"},
    {&ovsrec_controller_col_target, 0, NULL},
    {NULL, 0, NULL},
};

static const struct vsctl_column interface_columns[] = {
    {&ovsrec_interface_col_external_ids, 0, NULL},
    {&ovsrec_interface_col_ingress_policing_burst, 0, "[10,]"},
    {&ovsrec_interface_col_ingress_policing_rate, 0, "[100,]"},
    {&ovsrec_interface_col_mac, 0, MAC_RE},
    {&ovsrec_interface_col_name, VSCF_READONLY, NULL},
    {&ovsrec_interface_col_ofport, VSCF_READONLY, NULL},
    {&ovsrec_interface_col_options, 0, NULL},
    {&ovsrec_interface_col_type, VSCF_READONLY, NULL},
    {NULL, 0, NULL},
};

static const struct vsctl_column mirror_columns[] = {
    {&ovsrec_mirror_col_name, VSCF_READONLY, NULL},
    {&ovsrec_mirror_col_output_port, 0, "Port"},
    {&ovsrec_mirror_col_output_vlan, 0, "[1,4095]"},
    {&ovsrec_mirror_col_select_dst_port, 0, "Port"},
    {&ovsrec_mirror_col_select_src_port, 0, "Port"},
    {&ovsrec_mirror_col_select_vlan, 0, "[1,4095]"},
    {NULL, 0, NULL},
};

static const struct vsctl_column netflow_columns[] = {
    {&ovsrec_netflow_col_active_timeout, 0, "[-1,]"},
    {&ovsrec_netflow_col_add_id_to_interface, 0, NULL},
    {&ovsrec_netflow_col_engine_id, 0, "[0,255]"},
    {&ovsrec_netflow_col_engine_type, 0, "[0,255]"},
    {&ovsrec_netflow_col_targets, 0, IP_RE":"PORT_RE},
    {NULL, 0, NULL},
};

static const struct vsctl_column open_vswitch_columns[] = {
    {&ovsrec_open_vswitch_col_bridges, VSCF_READONLY, NULL},
    {&ovsrec_open_vswitch_col_controller, VSCF_READONLY, NULL},
    {&ovsrec_open_vswitch_col_cur_cfg, VSCF_HIDDEN, NULL},
    {&ovsrec_open_vswitch_col_managers, 0, "p?(ssl|tcp|unix):.*"},
    {&ovsrec_open_vswitch_col_next_cfg, VSCF_HIDDEN, NULL},
    {&ovsrec_open_vswitch_col_ssl, VSCF_READONLY, NULL},
    {NULL, 0, NULL},
};

static const struct vsctl_column port_columns[] = {
    {&ovsrec_port_col_bond_downdelay, 0, "[0,]"},
    {&ovsrec_port_col_bond_fake_iface, VSCF_READONLY, NULL},
    {&ovsrec_port_col_bond_updelay, 0, "[0,]"},
    {&ovsrec_port_col_external_ids, 0, NULL},
    {&ovsrec_port_col_fake_bridge, VSCF_READONLY, NULL},
    {&ovsrec_port_col_interfaces, VSCF_READONLY, NULL},
    {&ovsrec_port_col_mac, 0, MAC_RE},
    {&ovsrec_port_col_name, VSCF_READONLY, NULL},
    {&ovsrec_port_col_other_config, 0, NULL},
    {&ovsrec_port_col_tag, 0, "[0,4095]"},
    {&ovsrec_port_col_trunks, 0, "[0,4095]"},
    {NULL, 0, NULL},
};

static const struct vsctl_column ssl_columns[] = {
    {&ovsrec_ssl_col_bootstrap_ca_cert, 0, NULL},
    {&ovsrec_ssl_col_ca_cert, 0, NULL},
    {&ovsrec_ssl_col_certificate, 0, NULL},
    {&ovsrec_ssl_col_private_key, 0, NULL},
    {NULL, 0, NULL},
};

struct vsctl_row_id {
    const struct ovsdb_idl_table_class *table;
    const struct ovsdb_idl_column *name_column;
    const struct ovsdb_idl_column *uuid_column;
};

struct vsctl_table_class {
    struct ovsdb_idl_table_class *class;
    const struct vsctl_column *columns;
    struct vsctl_row_id row_ids[2];
};

static const struct vsctl_table_class tables[] = {
    {&ovsrec_table_bridge, bridge_columns,
     {{&ovsrec_table_bridge, &ovsrec_bridge_col_name, NULL},
      {NULL, NULL, NULL}}},

    {&ovsrec_table_controller, controller_columns,
     {{&ovsrec_table_bridge,
       &ovsrec_bridge_col_name,
       &ovsrec_bridge_col_controller},
      {&ovsrec_table_open_vswitch,
       NULL,
       &ovsrec_open_vswitch_col_controller}}},

    {&ovsrec_table_interface, interface_columns,
     {{&ovsrec_table_interface, &ovsrec_interface_col_name, NULL},
      {NULL, NULL, NULL}}},

    {&ovsrec_table_mirror, mirror_columns,
     {{&ovsrec_table_mirror, &ovsrec_mirror_col_name, NULL},
      {NULL, NULL, NULL}}},

    {&ovsrec_table_netflow, netflow_columns,
     {{&ovsrec_table_bridge,
       &ovsrec_bridge_col_name,
       &ovsrec_bridge_col_netflow},
      {NULL, NULL, NULL}}},

    {&ovsrec_table_open_vswitch, open_vswitch_columns,
     {{&ovsrec_table_open_vswitch, NULL, NULL},
      {NULL, NULL, NULL}}},

    {&ovsrec_table_port, port_columns,
     {{&ovsrec_table_port, &ovsrec_port_col_name, NULL},
      {NULL, NULL, NULL}}},

    {&ovsrec_table_ssl, ssl_columns,
     {{&ovsrec_table_open_vswitch, NULL, &ovsrec_open_vswitch_col_ssl}}},

    {NULL, NULL, {{NULL, NULL, NULL}, {NULL, NULL, NULL}}}
};

static void
die_if_error(char *error)
{
    if (error) {
        vsctl_fatal("%s", error);
    }
}

static int
to_lower_and_underscores(unsigned c)
{
    return c == '-' ? '_' : tolower(c);
}

static unsigned int
score_partial_match(const char *name, const char *s)
{
    int score;

    if (!strcmp(name, s)) {
        return UINT_MAX;
    }
    for (score = 0; ; score++, name++, s++) {
        if (to_lower_and_underscores(*name) != to_lower_and_underscores(*s)) {
            break;
        } else if (*name == '\0') {
            return UINT_MAX - 1;
        }
    }
    return *s == '\0' ? score : 0;
}

static const struct vsctl_table_class *
get_table(const char *table_name)
{
    const struct vsctl_table_class *table;
    const struct vsctl_table_class *best_match = NULL;
    unsigned int best_score = 0;

    for (table = tables; table->class; table++) {
        unsigned int score = score_partial_match(table->class->name,
                                                 table_name);
        if (score > best_score) {
            best_match = table;
            best_score = score;
        } else if (score == best_score) {
            best_match = NULL;
        }
    }
    if (best_match) {
        return best_match;
    } else if (best_score) {
        vsctl_fatal("multiple table names match \"%s\"", table_name);
    } else {
        vsctl_fatal("unknown table \"%s\"", table_name);
    }
}

static const struct ovsdb_idl_row *
get_row_by_id(struct vsctl_context *ctx, const struct vsctl_table_class *table,
              const struct vsctl_row_id *id, const char *record_id)
{
    const struct ovsdb_idl_row *referrer, *final;

    if (!id->table) {
        return NULL;
    }

    if (!id->name_column) {
        if (strcmp(record_id, ".")) {
            return NULL;
        }
        referrer = ovsdb_idl_first_row(ctx->idl, id->table);
        if (!referrer || ovsdb_idl_next_row(referrer)) {
            return NULL;
        }
    } else {
        const struct ovsdb_idl_row *row;
        unsigned int best_score = 0;

        /* It might make sense to relax this assertion. */
        assert(id->name_column->type.key_type == OVSDB_TYPE_STRING);

        referrer = NULL;
        for (row = ovsdb_idl_first_row(ctx->idl, id->table);
             row != NULL && best_score != UINT_MAX;
             row = ovsdb_idl_next_row(row))
        {
            struct ovsdb_datum name;

            ovsdb_idl_txn_read(row, id->name_column, &name);
            if (name.n == 1) {
                unsigned int score = score_partial_match(name.keys[0].string,
                                                         record_id);
                if (score > best_score) {
                    referrer = row;
                    best_score = score;
                } else if (score == best_score) {
                    referrer = NULL;
                }
            }
            ovsdb_datum_destroy(&name, &id->name_column->type);
        }
        if (best_score && !referrer) {
            vsctl_fatal("multiple rows in %s match \"%s\"",
                        table->class->name, record_id);
        }
    }
    if (!referrer) {
        return NULL;
    }

    final = NULL;
    if (id->uuid_column) {
        struct ovsdb_datum uuid;

        assert(id->uuid_column->type.key_type == OVSDB_TYPE_UUID);
        assert(id->uuid_column->type.value_type == OVSDB_TYPE_VOID);

        ovsdb_idl_txn_read(referrer, id->uuid_column, &uuid);
        if (uuid.n == 1) {
            final = ovsdb_idl_get_row_for_uuid(ctx->idl, table->class,
                                               &uuid.keys[0].uuid);
        }
        ovsdb_datum_destroy(&uuid, &id->uuid_column->type);
    } else {
        final = referrer;
    }

    return final;
}

static const struct ovsdb_idl_row *
get_row(struct vsctl_context *ctx,
        const struct vsctl_table_class *table, const char *record_id)
{
    const struct ovsdb_idl_row *row;
    struct uuid uuid;

    if (uuid_from_string(&uuid, record_id)) {
        row = ovsdb_idl_get_row_for_uuid(ctx->idl, table->class, &uuid);
    } else {
        int i;

        for (i = 0; i < ARRAY_SIZE(table->row_ids); i++) {
            row = get_row_by_id(ctx, table, &table->row_ids[i], record_id);
            if (row) {
                break;
            }
        }
    }
    return row;
}

static const struct ovsdb_idl_row *
must_get_row(struct vsctl_context *ctx,
             const struct vsctl_table_class *table, const char *record_id)
{
    const struct ovsdb_idl_row *row = get_row(ctx, table, record_id);
    if (!row) {
        vsctl_fatal("no row \"%s\" in table %s",
                    record_id, table->class->name);
    }
    return row;
}

static char *
get_column(const struct vsctl_table_class *table, const char *column_name,
           const struct vsctl_column **columnp)
{
    const struct vsctl_column *column;
    const struct vsctl_column *best_match = NULL;
    unsigned int best_score = 0;

    for (column = table->columns; column->idl; column++) {
        if (!(column->flags & VSCF_HIDDEN)) {
            unsigned int score = score_partial_match(column->idl->name,
                                                     column_name);
            if (score > best_score) {
                best_match = column;
                best_score = score;
            } else if (score == best_score) {
                best_match = NULL;
            }
        }
    }

    *columnp = best_match;
    if (best_match) {
        return NULL;
    } else if (best_score) {
        return xasprintf("%s contains more than one column whose name "
                         "matches \"%s\"", table->class->name, column_name);
    } else {
        return xasprintf("%s does not contain a column whose name matches "
                         "\"%s\"", table->class->name, column_name);
    }
}

static char * WARN_UNUSED_RESULT
parse_column_key_value(const char *arg, const struct vsctl_table_class *table,
                       const struct vsctl_column **columnp,
                       char **keyp, char **valuep)
{
    const char *p = arg;
    char *error;

    assert(columnp || keyp);
    if (keyp) {
        *keyp = NULL;
    }
    if (valuep) {
        *valuep = NULL;
    }

    /* Parse column name. */
    if (columnp) {
        char *column_name;

        error = ovsdb_token_parse(&p, &column_name);
        if (error) {
            goto error;
        }
        if (column_name[0] == '\0') {
            free(column_name);
            error = xasprintf("%s: missing column name", arg);
            goto error;
        }
        error = get_column(table, column_name, columnp);
        free(column_name);
        if (error) {
            goto error;
        }
    }

    /* Parse key string. */
    if (*p == ':' || !columnp) {
        if (columnp) {
            p++;
        } else if (!keyp) {
            error = xasprintf("%s: key not accepted here", arg);
            goto error;
        }
        error = ovsdb_token_parse(&p, keyp);
        if (error) {
            goto error;
        }
    } else if (keyp) {
        *keyp = NULL;
    }

    /* Parse value string. */
    if (*p == '=') {
        if (!valuep) {
            error = xasprintf("%s: value not accepted here", arg);
            goto error;
        }
        *valuep = xstrdup(p + 1);
    } else {
        if (valuep) {
            *valuep = NULL;
        }
        if (*p != '\0') {
            error = xasprintf("%s: trailing garbage \"%s\" in argument",
                              arg, p);
            goto error;
        }
    }
    return NULL;

error:
    if (columnp) {
        *columnp = NULL;
    }
    if (keyp) {
        free(*keyp);
        *keyp = NULL;
    }
    if (valuep) {
        free(*valuep);
        *valuep = NULL;
    }
    return error;
}

static void
cmd_get(struct vsctl_context *ctx)
{
    bool if_exists = shash_find(&ctx->options, "--if-exists");
    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;
    struct ds *out = &ctx->output;
    int i;

    table = get_table(table_name);
    row = must_get_row(ctx, table, record_id);
    for (i = 3; i < ctx->argc; i++) {
        const struct vsctl_column *column;
        struct ovsdb_datum datum;
        char *key_string;

        die_if_error(parse_column_key_value(ctx->argv[i], table,
                                            &column, &key_string, NULL));

        ovsdb_idl_txn_read(row, column->idl, &datum);
        if (key_string) {
            union ovsdb_atom key;
            unsigned int idx;

            if (column->idl->type.value_type == OVSDB_TYPE_VOID) {
                vsctl_fatal("cannot specify key to get for non-map column %s",
                            column->idl->name);
            }

            die_if_error(ovsdb_atom_from_string(&key,
                                                column->idl->type.key_type,
                                                key_string));

            idx = ovsdb_datum_find_key(&datum, &key,
                                       column->idl->type.key_type);
            if (idx == UINT_MAX) {
                if (!if_exists) {
                    vsctl_fatal("no key \"%s\" in %s record \"%s\" column %s",
                                key_string, table->class->name, record_id,
                                column->idl->name);
                }
            } else {
                ovsdb_atom_to_string(&datum.values[idx],
                                     column->idl->type.value_type, out);
            }
            ovsdb_atom_destroy(&key, column->idl->type.key_type);
        } else {
            ovsdb_datum_to_string(&datum, &column->idl->type, out);
        }
        ds_put_char(out, '\n');
        ovsdb_datum_destroy(&datum, &column->idl->type);

        free(key_string);
    }
}

static void
list_record(const struct vsctl_table_class *table,
            const struct ovsdb_idl_row *row, struct ds *out)
{
    const struct vsctl_column *column;

    ds_put_format(out, "%-20s (RO): "UUID_FMT"\n", "_uuid",
                  UUID_ARGS(&row->uuid));
    for (column = table->columns; column->idl; column++) {
        struct ovsdb_datum datum;

        if (column->flags & VSCF_HIDDEN) {
            continue;
        }

        ovsdb_idl_txn_read(row, column->idl, &datum);

        ds_put_format(out, "%-20s (%s): ", column->idl->name,
                      column->flags & VSCF_READONLY ? "RO" : "RW");
        ovsdb_datum_to_string(&datum, &column->idl->type, out);
        ds_put_char(out, '\n');

        ovsdb_datum_destroy(&datum, &column->idl->type);
    }
}

static void
cmd_list(struct vsctl_context *ctx)
{
    const char *table_name = ctx->argv[1];
    const struct vsctl_table_class *table;
    struct ds *out = &ctx->output;
    int i;

    table = get_table(table_name);
    if (ctx->argc > 2) {
        for (i = 2; i < ctx->argc; i++) {
            if (i > 2) {
                ds_put_char(out, '\n');
            }
            list_record(table, must_get_row(ctx, table, ctx->argv[i]), out);
        }
    } else {
        const struct ovsdb_idl_row *row;
        bool first;

        for (row = ovsdb_idl_first_row(ctx->idl, table->class), first = true;
             row != NULL;
             row = ovsdb_idl_next_row(row), first = false) {
            if (!first) {
                ds_put_char(out, '\n');
            }
            list_record(table, row, out);
        }
    }
}

static void
check_string_constraint(const struct ovsdb_datum *datum,
                        const char *constraint)
{
    unsigned int i;
    char *regex;
    regex_t re;
    int retval;

    regex = xasprintf("^%s$", constraint);
    retval = regcomp(&re, regex, REG_NOSUB | REG_EXTENDED);
    if (retval) {
        size_t length = regerror(retval, &re, NULL, 0);
        char *buffer = xmalloc(length);
        regerror(retval, &re, buffer, length);
        vsctl_fatal("internal error compiling regular expression %s: %s",
                    regex, buffer);
    }

    for (i = 0; i < datum->n; i++) {
        const char *key = datum->keys[i].string;
        if (regexec(&re, key, 0, NULL, 0)) {
            vsctl_fatal("%s is not valid (it does not match %s)", key, regex);
        }
    }
    free(regex);
    regfree(&re);
}

static void
check_integer_constraint(const struct ovsdb_datum *datum,
                         const char *constraint)
{
    int64_t min, max;
    unsigned int i;
    int n = -1;

    sscanf(constraint, "[%"SCNd64",%"SCNd64"]%n", &min, &max, &n);
    if (n == -1) {
        sscanf(constraint, "[%"SCNd64",]%n", &min, &n);
        if (n == -1) {
            sscanf(constraint, "[,%"SCNd64"]%n", &max, &n);
            if (n == -1) {
                VLOG_DBG("internal error: bad integer contraint \"%s\"",
                         constraint);
                return;
            } else {
                min = INT64_MIN;
            }
        } else {
            max = INT64_MAX;
        }
    }

    for (i = 0; i < datum->n; i++) {
        int64_t value = datum->keys[i].integer;
        if (value < min || value > max) {
            if (max == INT64_MAX) {
                vsctl_fatal("%"PRId64" is less than the minimum "
                            "allowed value %"PRId64, value, min);
            } else if (min == INT64_MIN) {
                vsctl_fatal("%"PRId64" is greater than the maximum "
                            "allowed value %"PRId64, value, max);
            } else {
                vsctl_fatal("%"PRId64" is outside the valid range %"PRId64" "
                            "to %"PRId64" (inclusive)", value, min, max);
            }
        }
    }
}

static void
check_constraint(const struct ovsdb_datum *datum,
                 const struct ovsdb_type *type, const char *constraint)
{
    if (constraint && datum->n) {
        if (type->key_type == OVSDB_TYPE_STRING) {
            check_string_constraint(datum, constraint);
        } else if (type->key_type == OVSDB_TYPE_INTEGER) {
            check_integer_constraint(datum, constraint);
        }
    }
}

static void
set_column(const struct vsctl_table_class *table,
           const struct ovsdb_idl_row *row,
           const char *arg, bool force)
{
    const struct vsctl_column *column;
    char *key_string, *value_string;
    char *error;

    error = parse_column_key_value(arg, table, &column, &key_string,
                                   &value_string);
    die_if_error(error);
    if (column->flags & VSCF_READONLY && !force) {
        vsctl_fatal("%s: cannot modify read-only column %s in table %s",
                    arg, column->idl->name, table->class->name);
    }
    if (!value_string) {
        vsctl_fatal("%s: missing value", arg);
    }

    if (key_string) {
        union ovsdb_atom key, value;
        struct ovsdb_datum old, new;

        if (column->idl->type.value_type == OVSDB_TYPE_VOID) {
            vsctl_fatal("cannot specify key to set for non-map column %s",
                        column->idl->name);
        }

        die_if_error(ovsdb_atom_from_string(&key,
                                            column->idl->type.key_type,
                                            key_string));
        die_if_error(ovsdb_atom_from_string(&value,
                                            column->idl->type.value_type,
                                            value_string));

        ovsdb_datum_init_empty(&new);
        ovsdb_datum_add_unsafe(&new, &key, &value, &column->idl->type);

        ovsdb_atom_destroy(&key, column->idl->type.key_type);
        ovsdb_atom_destroy(&value, column->idl->type.value_type);

        ovsdb_idl_txn_read(row, column->idl, &old);
        ovsdb_datum_union(&old, &new, &column->idl->type, true);
        ovsdb_idl_txn_write(row, column->idl, &old);

        ovsdb_datum_destroy(&new, &column->idl->type);
    } else {
        struct ovsdb_datum datum;

        die_if_error(ovsdb_datum_from_string(&datum, &column->idl->type,
                                             value_string));
        if (!force) {
            check_constraint(&datum, &column->idl->type,
                             column->constraint);
        }
        ovsdb_idl_txn_write(row, column->idl, &datum);
    }

    free(key_string);
    free(value_string);
}

static void
cmd_set(struct vsctl_context *ctx)
{
    bool force = shash_find(&ctx->options, "--force");
    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++) {
        set_column(table, row, ctx->argv[i], force);
    }
}

static void
cmd_add(struct vsctl_context *ctx)
{
    bool force = shash_find(&ctx->options, "--force");
    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 vsctl_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));
    if (column->flags & VSCF_READONLY && !force) {
        vsctl_fatal("cannot modify read-only column %s in table %s",
                    column->idl->name, table->class->name);
    }

    type = &column->idl->type;
    ovsdb_idl_txn_read(row, column->idl, &old);
    for (i = 4; i < ctx->argc; i++) {
        struct ovsdb_type add_type;
        struct ovsdb_datum add;

        add_type = *type;
        add_type.n_min = 1;
        add_type.n_max = UINT_MAX;
        die_if_error(ovsdb_datum_from_string(&add, &add_type, ctx->argv[i]));
        ovsdb_datum_union(&old, &add, type, false);
        ovsdb_datum_destroy(&add, type);
    }
    if (old.n > type->n_max) {
        vsctl_fatal("\"add\" operation would put %u %s in column %s of "
                    "table %s but the maximum number is %u",
                    old.n,
                    type->value_type == OVSDB_TYPE_VOID ? "values" : "pairs",
                    column->idl->name, table->class->name, type->n_max);
    }
    ovsdb_idl_txn_write(row, column->idl, &old);
}

static void
cmd_remove(struct vsctl_context *ctx)
{
    bool force = shash_find(&ctx->options, "--force");
    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 vsctl_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));
    if (column->flags & VSCF_READONLY && !force) {
        vsctl_fatal("cannot modify read-only column %s in table %s",
                    column->idl->name, table->class->name);
    }

    type = &column->idl->type;
    ovsdb_idl_txn_read(row, column->idl, &old);
    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]);
        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]));
        }
        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 minimun number is %u",
                    old.n,
                    type->value_type == OVSDB_TYPE_VOID ? "values" : "pairs",
                    column->idl->name, table->class->name, type->n_min);
    }
    ovsdb_idl_txn_write(row, column->idl, &old);
}

static void
cmd_clear(struct vsctl_context *ctx)
{
    bool force = shash_find(&ctx->options, "--force");
    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 vsctl_column *column;
        const struct ovsdb_type *type;
        struct ovsdb_datum datum;

        die_if_error(get_column(table, ctx->argv[i], &column));

        type = &column->idl->type;
        if (column->flags & VSCF_READONLY && !force) {
            vsctl_fatal("cannot modify read-only column %s in table %s",
                        column->idl->name, table->class->name);
        } else 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->idl->name, table->class->name);
        }

        ovsdb_datum_init_empty(&datum);
        ovsdb_idl_txn_write(row, column->idl, &datum);
    }
}

static void
cmd_create(struct vsctl_context *ctx)
{
    bool force = shash_find(&ctx->options, "--force");
    const char *table_name = ctx->argv[1];
    const struct vsctl_table_class *table;
    const struct ovsdb_idl_row *row;
    int i;

    if (!force) {
        vsctl_fatal("\"create\" requires --force");
    }

    table = get_table(table_name);
    row = ovsdb_idl_txn_insert(ctx->txn, table->class);
    for (i = 2; i < ctx->argc; i++) {
        set_column(table, row, ctx->argv[i], force);
    }
    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;

    uuid_from_string(&dummy, ds_cstr(&ctx->output));
    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
cmd_destroy(struct vsctl_context *ctx)
{
    bool force = shash_find(&ctx->options, "--force");
    bool must_exist = !shash_find(&ctx->options, "--if-exists");
    const char *table_name = ctx->argv[1];
    const struct vsctl_table_class *table;
    int i;

    if (!force) {
        vsctl_fatal("\"destroy\" requires --force");
    }

    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);
        }
    }
}
\f
static struct json *
where_uuid_equals(const struct uuid *uuid)
{
    return
        json_array_create_1(
            json_array_create_3(
                json_string_create("_uuid"),
                json_string_create("=="),
                json_array_create_2(
                    json_string_create("uuid"),
                    json_string_create_nocopy(
                        xasprintf(UUID_FMT, UUID_ARGS(uuid))))));
}

static void
vsctl_context_init(struct vsctl_context *ctx, struct vsctl_command *command,
                   struct ovsdb_idl *idl, struct ovsdb_idl_txn *txn,
                   const struct ovsrec_open_vswitch *ovs)
{
    ctx->argc = command->argc;
    ctx->argv = command->argv;
    ctx->options = command->options;

    ds_swap(&ctx->output, &command->output);
    ctx->idl = idl;
    ctx->txn = txn;
    ctx->ovs = ovs;

}

static void
vsctl_context_done(struct vsctl_context *ctx, struct vsctl_command *command)
{
    ds_swap(&ctx->output, &command->output);
}

static void
do_vsctl(const char *args, struct vsctl_command *commands, size_t n_commands,
         struct ovsdb_idl *idl)
{
    struct ovsdb_idl_txn *txn;
    const struct ovsrec_open_vswitch *ovs;
    enum ovsdb_idl_txn_status status;
    struct vsctl_command *c;
    int64_t next_cfg = 0;
    char *comment;

    txn = the_idl_txn = ovsdb_idl_txn_create(idl);
    if (dry_run) {
        ovsdb_idl_txn_set_dry_run(txn);
    }

    comment = xasprintf("ovs-vsctl: %s", args);
    ovsdb_idl_txn_add_comment(txn, comment);
    free(comment);

    ovs = ovsrec_open_vswitch_first(idl);
    if (!ovs) {
        /* XXX add verification that table is empty */
        ovs = ovsrec_open_vswitch_insert(txn);
    }

    if (wait_for_reload) {
        struct json *where = where_uuid_equals(&ovs->header_.uuid);
        ovsdb_idl_txn_increment(txn, "Open_vSwitch", "next_cfg", where);
        json_destroy(where);
    }

    for (c = commands; c < &commands[n_commands]; c++) {
        struct vsctl_context ctx;

        ds_init(&c->output);
        vsctl_context_init(&ctx, c, idl, txn, ovs);
        (c->syntax->run)(&ctx);
        vsctl_context_done(&ctx, c);
    }

    while ((status = ovsdb_idl_txn_commit(txn)) == TXN_INCOMPLETE) {
        ovsdb_idl_run(idl);
        ovsdb_idl_wait(idl);
        ovsdb_idl_txn_wait(txn);
        poll_block();
    }
    if (wait_for_reload && status == TXN_SUCCESS) {
        next_cfg = ovsdb_idl_txn_get_increment_new_value(txn);
    }
    for (c = commands; c < &commands[n_commands]; c++) {
        if (c->syntax->postprocess) {
            struct vsctl_context ctx;

            vsctl_context_init(&ctx, c, idl, txn, ovs);
            (c->syntax->postprocess)(&ctx);
            vsctl_context_done(&ctx, c);
        }
    }
    ovsdb_idl_txn_destroy(txn);
    the_idl_txn = NULL;

    switch (status) {
    case TXN_INCOMPLETE:
        NOT_REACHED();

    case TXN_ABORTED:
        /* Should not happen--we never call ovsdb_idl_txn_abort(). */
        vsctl_fatal("transaction aborted");

    case TXN_UNCHANGED:
    case TXN_SUCCESS:
        break;

    case TXN_TRY_AGAIN:
        for (c = commands; c < &commands[n_commands]; c++) {
            ds_destroy(&c->output);
        }
        return;

    case TXN_ERROR:
        vsctl_fatal("transaction error");

    default:
        NOT_REACHED();
    }

    for (c = commands; c < &commands[n_commands]; c++) {
        struct ds *ds = &c->output;
        if (oneline) {
            size_t j;

            ds_chomp(ds, '\n');
            for (j = 0; j < ds->length; j++) {
                int c = ds->string[j];
                switch (c) {
                case '\n':
                    fputs("\\n", stdout);
                    break;

                case '\\':
                    fputs("\\\\", stdout);
                    break;

                default:
                    putchar(c);
                }
            }
            putchar('\n');
        } else {
            fputs(ds_cstr(ds), stdout);
        }
        ds_destroy(&c->output);
        shash_destroy(&c->options);
    }
    free(commands);

    if (wait_for_reload && status != TXN_UNCHANGED) {
        for (;;) {
            const struct ovsrec_open_vswitch *ovs;

            ovsdb_idl_run(idl);
            OVSREC_OPEN_VSWITCH_FOR_EACH (ovs, idl) {
                if (ovs->cur_cfg >= next_cfg) {
                    goto done;
                }
            }
            ovsdb_idl_wait(idl);
            poll_block();
        }
    done: ;
    }
    ovsdb_idl_destroy(idl);

    exit(EXIT_SUCCESS);
}

static const struct vsctl_command_syntax all_commands[] = {
    /* Open vSwitch commands. */
    {"init", 0, 0, cmd_init, NULL, ""},

    /* Bridge commands. */
    {"add-br", 1, 3, cmd_add_br, NULL, ""},
    {"del-br", 1, 1, cmd_del_br, NULL, "--if-exists"},
    {"list-br", 0, 0, cmd_list_br, NULL, ""},
    {"br-exists", 1, 1, cmd_br_exists, NULL, ""},
    {"br-to-vlan", 1, 1, cmd_br_to_vlan, NULL, ""},
    {"br-to-parent", 1, 1, cmd_br_to_parent, NULL, ""},
    {"br-set-external-id", 2, 3, cmd_br_set_external_id, NULL, ""},
    {"br-get-external-id", 1, 2, cmd_br_get_external_id, NULL, ""},

    /* Port commands. */
    {"list-ports", 1, 1, cmd_list_ports, NULL, ""},
    {"add-port", 2, 2, cmd_add_port, NULL, ""},
    {"add-bond", 4, INT_MAX, cmd_add_bond, NULL, "--fake-iface"},
    {"del-port", 1, 2, cmd_del_port, NULL, "--if-exists"},
    {"port-to-br", 1, 1, cmd_port_to_br, NULL, ""},

    /* Interface commands. */
    {"list-ifaces", 1, 1, cmd_list_ifaces, NULL, ""},
    {"iface-to-br", 1, 1, cmd_iface_to_br, NULL, ""},

    /* Controller commands. */
    {"get-controller", 0, 1, cmd_get_controller, NULL, ""},
    {"del-controller", 0, 1, cmd_del_controller, NULL, ""},
    {"set-controller", 1, 2, cmd_set_controller, NULL, ""},
    {"get-fail-mode", 0, 1, cmd_get_fail_mode, NULL, ""},
    {"del-fail-mode", 0, 1, cmd_del_fail_mode, NULL, ""},
    {"set-fail-mode", 1, 2, cmd_set_fail_mode, NULL, ""},

    /* SSL commands. */
    {"get-ssl", 0, 0, cmd_get_ssl, NULL, ""},
    {"del-ssl", 0, 0, cmd_del_ssl, NULL, ""},
    {"set-ssl", 3, 3, cmd_set_ssl, NULL, "--bootstrap"},

    /* Parameter commands. */
    {"get", 3, INT_MAX, cmd_get, NULL, "--if-exists"},
    {"list", 1, INT_MAX, cmd_list, NULL, ""},
    {"set", 3, INT_MAX, cmd_set, NULL, "--force"},
    {"add", 4, INT_MAX, cmd_add, NULL, "--force"},
    {"remove", 4, INT_MAX, cmd_remove, NULL, "--force"},
    {"clear", 3, INT_MAX, cmd_clear, NULL, "--force"},
    {"create", 2, INT_MAX, cmd_create, post_create, "--force"},
    {"destroy", 1, INT_MAX, cmd_destroy, NULL, "--force,--if-exists"},

    {NULL, 0, 0, NULL, NULL, NULL},
};