ovsdb/jsonrpc-server.c

   1 /* Copyright (c) 2009, 2010, 2011, 2012 Nicira Networks
   2  *
   3  * Licensed under the Apache License, Version 2.0 (the "License");
   4  * you may not use this file except in compliance with the License.
   5  * You may obtain a copy of the License at:
   6  *
   7  *     http://www.apache.org/licenses/LICENSE-2.0
   8  *
   9  * Unless required by applicable law or agreed to in writing, software
  10  * distributed under the License is distributed on an "AS IS" BASIS,
  11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12  * See the License for the specific language governing permissions and
  13  * limitations under the License.
  14  */
  15
  16 #include <config.h>
  17
  18 #include "jsonrpc-server.h"
  19
  20 #include <assert.h>
  21 #include <errno.h>
  22
  23 #include "bitmap.h"
  24 #include "column.h"
  25 #include "dynamic-string.h"
  26 #include "json.h"
  27 #include "jsonrpc.h"
  28 #include "ovsdb-error.h"
  29 #include "ovsdb-parser.h"
  30 #include "ovsdb.h"
  31 #include "reconnect.h"
  32 #include "row.h"
  33 #include "server.h"
  34 #include "stream.h"
  35 #include "table.h"
  36 #include "timeval.h"
  37 #include "transaction.h"
  38 #include "trigger.h"
  39 #include "vlog.h"
  40
  41 VLOG_DEFINE_THIS_MODULE(ovsdb_jsonrpc_server);
  42
  43 struct ovsdb_jsonrpc_remote;
  44 struct ovsdb_jsonrpc_session;
  45
  46 /* Message rate-limiting. */
  47 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
  48
  49 /* Sessions. */
  50 static struct ovsdb_jsonrpc_session *ovsdb_jsonrpc_session_create(
  51     struct ovsdb_jsonrpc_remote *, struct jsonrpc_session *);
  52 static void ovsdb_jsonrpc_session_run_all(struct ovsdb_jsonrpc_remote *);
  53 static void ovsdb_jsonrpc_session_wait_all(struct ovsdb_jsonrpc_remote *);
  54 static void ovsdb_jsonrpc_session_close_all(struct ovsdb_jsonrpc_remote *);
  55 static void ovsdb_jsonrpc_session_reconnect_all(struct ovsdb_jsonrpc_remote *);
  56 static void ovsdb_jsonrpc_session_set_all_options(
  57     struct ovsdb_jsonrpc_remote *, const struct ovsdb_jsonrpc_options *);
  58 static bool ovsdb_jsonrpc_session_get_status(
  59     const struct ovsdb_jsonrpc_remote *,
  60     struct ovsdb_jsonrpc_remote_status *);
  61 static void ovsdb_jsonrpc_session_unlock_all(struct ovsdb_jsonrpc_session *);
  62 static void ovsdb_jsonrpc_session_unlock__(struct ovsdb_lock_waiter *);
  63
  64 /* Triggers. */
  65 static void ovsdb_jsonrpc_trigger_create(struct ovsdb_jsonrpc_session *,
  66                                          struct json *id, struct json *params);
  67 static struct ovsdb_jsonrpc_trigger *ovsdb_jsonrpc_trigger_find(
  68     struct ovsdb_jsonrpc_session *, const struct json *id, size_t hash);
  69 static void ovsdb_jsonrpc_trigger_complete(struct ovsdb_jsonrpc_trigger *);
  70 static void ovsdb_jsonrpc_trigger_complete_all(struct ovsdb_jsonrpc_session *);
  71 static void ovsdb_jsonrpc_trigger_complete_done(
  72     struct ovsdb_jsonrpc_session *);
  73
  74 /* Monitors. */
  75 static struct json *ovsdb_jsonrpc_monitor_create(
  76     struct ovsdb_jsonrpc_session *, struct json *params);
  77 static struct jsonrpc_msg *ovsdb_jsonrpc_monitor_cancel(
  78     struct ovsdb_jsonrpc_session *,
  79     struct json_array *params,
  80     const struct json *request_id);
  81 static void ovsdb_jsonrpc_monitor_remove_all(struct ovsdb_jsonrpc_session *);
  82 \f
  83 /* JSON-RPC database server. */
  84
  85 struct ovsdb_jsonrpc_server {
  86     struct ovsdb_server up;
  87     unsigned int n_sessions, max_sessions;
  88     struct shash remotes;      /* Contains "struct ovsdb_jsonrpc_remote *"s. */
  89 };
  90
  91 /* A configured remote.  This is either a passive stream listener plus a list
  92  * of the currently connected sessions, or a list of exactly one active
  93  * session. */
  94 struct ovsdb_jsonrpc_remote {
  95     struct ovsdb_jsonrpc_server *server;
  96     struct pstream *listener;   /* Listener, if passive. */
  97     struct list sessions;       /* List of "struct ovsdb_jsonrpc_session"s. */
  98 };
  99
 100 static struct ovsdb_jsonrpc_remote *ovsdb_jsonrpc_server_add_remote(
 101     struct ovsdb_jsonrpc_server *, const char *name,
 102     const struct ovsdb_jsonrpc_options *options
 103 );
 104 static void ovsdb_jsonrpc_server_del_remote(struct shash_node *);
 105
 106 struct ovsdb_jsonrpc_server *
 107 ovsdb_jsonrpc_server_create(struct ovsdb *db)
 108 {
 109     struct ovsdb_jsonrpc_server *server = xzalloc(sizeof *server);
 110     ovsdb_server_init(&server->up, db);
 111     server->max_sessions = 64;
 112     shash_init(&server->remotes);
 113     return server;
 114 }
 115
 116 void
 117 ovsdb_jsonrpc_server_destroy(struct ovsdb_jsonrpc_server *svr)
 118 {
 119     struct shash_node *node, *next;
 120
 121     SHASH_FOR_EACH_SAFE (node, next, &svr->remotes) {
 122         ovsdb_jsonrpc_server_del_remote(node);
 123     }
 124     shash_destroy(&svr->remotes);
 125     ovsdb_server_destroy(&svr->up);
 126     free(svr);
 127 }
 128
 129 struct ovsdb_jsonrpc_options *
 130 ovsdb_jsonrpc_default_options(void)
 131 {
 132     struct ovsdb_jsonrpc_options *options = xzalloc(sizeof *options);
 133     options->probe_interval = RECONNECT_DEFAULT_PROBE_INTERVAL;
 134     options->max_backoff = RECONNECT_DEFAULT_MAX_BACKOFF;
 135     return options;
 136 }
 137
 138 /* Sets 'svr''s current set of remotes to the names in 'new_remotes', with
 139  * options in the struct ovsdb_jsonrpc_options supplied as the data values.
 140  *
 141  * A remote is an active or passive stream connection method, e.g. "pssl:" or
 142  * "tcp:1.2.3.4". */
 143 void
 144 ovsdb_jsonrpc_server_set_remotes(struct ovsdb_jsonrpc_server *svr,
 145                                  const struct shash *new_remotes)
 146 {
 147     struct shash_node *node, *next;
 148
 149     SHASH_FOR_EACH_SAFE (node, next, &svr->remotes) {
 150         if (!shash_find(new_remotes, node->name)) {
 151             VLOG_INFO("%s: remote deconfigured", node->name);
 152             ovsdb_jsonrpc_server_del_remote(node);
 153         }
 154     }
 155     SHASH_FOR_EACH (node, new_remotes) {
 156         const struct ovsdb_jsonrpc_options *options = node->data;
 157         struct ovsdb_jsonrpc_remote *remote;
 158
 159         remote = shash_find_data(&svr->remotes, node->name);
 160         if (!remote) {
 161             remote = ovsdb_jsonrpc_server_add_remote(svr, node->name, options);
 162             if (!remote) {
 163                 continue;
 164             }
 165         }
 166
 167         ovsdb_jsonrpc_session_set_all_options(remote, options);
 168     }
 169 }
 170
 171 static struct ovsdb_jsonrpc_remote *
 172 ovsdb_jsonrpc_server_add_remote(struct ovsdb_jsonrpc_server *svr,
 173                                 const char *name,
 174                                 const struct ovsdb_jsonrpc_options *options)
 175 {
 176     struct ovsdb_jsonrpc_remote *remote;
 177     struct pstream *listener;
 178     int error;
 179
 180     error = jsonrpc_pstream_open(name, &listener, options->dscp);
 181     if (error && error != EAFNOSUPPORT) {
 182         VLOG_ERR_RL(&rl, "%s: listen failed: %s", name, strerror(error));
 183         return NULL;
 184     }
 185
 186     remote = xmalloc(sizeof *remote);
 187     remote->server = svr;
 188     remote->listener = listener;
 189     list_init(&remote->sessions);
 190     shash_add(&svr->remotes, name, remote);
 191
 192     if (!listener) {
 193         ovsdb_jsonrpc_session_create(remote, jsonrpc_session_open(name));
 194     }
 195     return remote;
 196 }
 197
 198 static void
 199 ovsdb_jsonrpc_server_del_remote(struct shash_node *node)
 200 {
 201     struct ovsdb_jsonrpc_remote *remote = node->data;
 202
 203     ovsdb_jsonrpc_session_close_all(remote);
 204     pstream_close(remote->listener);
 205     shash_delete(&remote->server->remotes, node);
 206     free(remote);
 207 }
 208
 209 /* Stores status information for the remote named 'target', which should have
 210  * been configured on 'svr' with a call to ovsdb_jsonrpc_server_set_remotes(),
 211  * into '*status'.  On success returns true, on failure (if 'svr' doesn't have
 212  * a remote named 'target' or if that remote is an inbound remote that has no
 213  * active connections) returns false.  On failure, 'status' will be zeroed.
 214  */
 215 bool
 216 ovsdb_jsonrpc_server_get_remote_status(
 217     const struct ovsdb_jsonrpc_server *svr, const char *target,
 218     struct ovsdb_jsonrpc_remote_status *status)
 219 {
 220     const struct ovsdb_jsonrpc_remote *remote;
 221
 222     memset(status, 0, sizeof *status);
 223
 224     remote = shash_find_data(&svr->remotes, target);
 225     return remote && ovsdb_jsonrpc_session_get_status(remote, status);
 226 }
 227
 228 void
 229 ovsdb_jsonrpc_server_free_remote_status(
 230     struct ovsdb_jsonrpc_remote_status *status)
 231 {
 232     free(status->locks_held);
 233     free(status->locks_waiting);
 234     free(status->locks_lost);
 235 }
 236
 237 /* Forces all of the JSON-RPC sessions managed by 'svr' to disconnect and
 238  * reconnect. */
 239 void
 240 ovsdb_jsonrpc_server_reconnect(struct ovsdb_jsonrpc_server *svr)
 241 {
 242     struct shash_node *node;
 243
 244     SHASH_FOR_EACH (node, &svr->remotes) {
 245         struct ovsdb_jsonrpc_remote *remote = node->data;
 246
 247         ovsdb_jsonrpc_session_reconnect_all(remote);
 248     }
 249 }
 250
 251 void
 252 ovsdb_jsonrpc_server_run(struct ovsdb_jsonrpc_server *svr)
 253 {
 254     struct shash_node *node;
 255
 256     SHASH_FOR_EACH (node, &svr->remotes) {
 257         struct ovsdb_jsonrpc_remote *remote = node->data;
 258
 259         if (remote->listener && svr->n_sessions < svr->max_sessions) {
 260             struct stream *stream;
 261             int error;
 262
 263             error = pstream_accept(remote->listener, &stream);
 264             if (!error) {
 265                 struct jsonrpc_session *js;
 266                 js = jsonrpc_session_open_unreliably(jsonrpc_open(stream));
 267                 ovsdb_jsonrpc_session_create(remote, js);
 268             } else if (error != EAGAIN) {
 269                 VLOG_WARN_RL(&rl, "%s: accept failed: %s",
 270                              pstream_get_name(remote->listener),
 271                              strerror(error));
 272             }
 273         }
 274
 275         ovsdb_jsonrpc_session_run_all(remote);
 276     }
 277 }
 278
 279 void
 280 ovsdb_jsonrpc_server_wait(struct ovsdb_jsonrpc_server *svr)
 281 {
 282     struct shash_node *node;
 283
 284     SHASH_FOR_EACH (node, &svr->remotes) {
 285         struct ovsdb_jsonrpc_remote *remote = node->data;
 286
 287         if (remote->listener && svr->n_sessions < svr->max_sessions) {
 288             pstream_wait(remote->listener);
 289         }
 290
 291         ovsdb_jsonrpc_session_wait_all(remote);
 292     }
 293 }
 294 \f
 295 /* JSON-RPC database server session. */
 296
 297 struct ovsdb_jsonrpc_session {
 298     struct list node;           /* Element in remote's sessions list. */
 299     struct ovsdb_session up;
 300     struct ovsdb_jsonrpc_remote *remote;
 301
 302     /* Triggers. */
 303     struct hmap triggers;       /* Hmap of "struct ovsdb_jsonrpc_trigger"s. */
 304
 305     /* Monitors. */
 306     struct hmap monitors;       /* Hmap of "struct ovsdb_jsonrpc_monitor"s. */
 307
 308     /* Network connectivity. */
 309     struct jsonrpc_session *js;  /* JSON-RPC session. */
 310     unsigned int js_seqno;       /* Last jsonrpc_session_get_seqno() value. */
 311 };
 312
 313 static void ovsdb_jsonrpc_session_close(struct ovsdb_jsonrpc_session *);
 314 static int ovsdb_jsonrpc_session_run(struct ovsdb_jsonrpc_session *);
 315 static void ovsdb_jsonrpc_session_wait(struct ovsdb_jsonrpc_session *);
 316 static void ovsdb_jsonrpc_session_set_options(
 317     struct ovsdb_jsonrpc_session *, const struct ovsdb_jsonrpc_options *);
 318 static void ovsdb_jsonrpc_session_got_request(struct ovsdb_jsonrpc_session *,
 319                                              struct jsonrpc_msg *);
 320 static void ovsdb_jsonrpc_session_got_notify(struct ovsdb_jsonrpc_session *,
 321                                              struct jsonrpc_msg *);
 322
 323 static struct ovsdb_jsonrpc_session *
 324 ovsdb_jsonrpc_session_create(struct ovsdb_jsonrpc_remote *remote,
 325                              struct jsonrpc_session *js)
 326 {
 327     struct ovsdb_jsonrpc_session *s;
 328
 329     s = xzalloc(sizeof *s);
 330     ovsdb_session_init(&s->up, remote->server->up.db);
 331     s->remote = remote;
 332     list_push_back(&remote->sessions, &s->node);
 333     hmap_init(&s->triggers);
 334     hmap_init(&s->monitors);
 335     s->js = js;
 336     s->js_seqno = jsonrpc_session_get_seqno(js);
 337
 338     remote->server->n_sessions++;
 339
 340     return s;
 341 }
 342
 343 static void
 344 ovsdb_jsonrpc_session_close(struct ovsdb_jsonrpc_session *s)
 345 {
 346     ovsdb_jsonrpc_monitor_remove_all(s);
 347     ovsdb_jsonrpc_session_unlock_all(s);
 348     jsonrpc_session_close(s->js);
 349     list_remove(&s->node);
 350     ovsdb_session_destroy(&s->up);
 351     s->remote->server->n_sessions--;
 352     ovsdb_session_destroy(&s->up);
 353     free(s);
 354 }
 355
 356 static int
 357 ovsdb_jsonrpc_session_run(struct ovsdb_jsonrpc_session *s)
 358 {
 359     jsonrpc_session_run(s->js);
 360     if (s->js_seqno != jsonrpc_session_get_seqno(s->js)) {
 361         s->js_seqno = jsonrpc_session_get_seqno(s->js);
 362         ovsdb_jsonrpc_trigger_complete_all(s);
 363         ovsdb_jsonrpc_monitor_remove_all(s);
 364         ovsdb_jsonrpc_session_unlock_all(s);
 365     }
 366
 367     ovsdb_jsonrpc_trigger_complete_done(s);
 368
 369     if (!jsonrpc_session_get_backlog(s->js)) {
 370         struct jsonrpc_msg *msg = jsonrpc_session_recv(s->js);
 371         if (msg) {
 372             if (msg->type == JSONRPC_REQUEST) {
 373                 ovsdb_jsonrpc_session_got_request(s, msg);
 374             } else if (msg->type == JSONRPC_NOTIFY) {
 375                 ovsdb_jsonrpc_session_got_notify(s, msg);
 376             } else {
 377                 VLOG_WARN("%s: received unexpected %s message",
 378                           jsonrpc_session_get_name(s->js),
 379                           jsonrpc_msg_type_to_string(msg->type));
 380                 jsonrpc_session_force_reconnect(s->js);
 381                 jsonrpc_msg_destroy(msg);
 382             }
 383         }
 384     }
 385     return jsonrpc_session_is_alive(s->js) ? 0 : ETIMEDOUT;
 386 }
 387
 388 static void
 389 ovsdb_jsonrpc_session_set_options(struct ovsdb_jsonrpc_session *session,
 390                                   const struct ovsdb_jsonrpc_options *options)
 391 {
 392     jsonrpc_session_set_max_backoff(session->js, options->max_backoff);
 393     jsonrpc_session_set_probe_interval(session->js, options->probe_interval);
 394     jsonrpc_session_set_dscp(session->js, options->dscp);
 395 }
 396
 397 static void
 398 ovsdb_jsonrpc_session_run_all(struct ovsdb_jsonrpc_remote *remote)
 399 {
 400     struct ovsdb_jsonrpc_session *s, *next;
 401
 402     LIST_FOR_EACH_SAFE (s, next, node, &remote->sessions) {
 403         int error = ovsdb_jsonrpc_session_run(s);
 404         if (error) {
 405             ovsdb_jsonrpc_session_close(s);
 406         }
 407     }
 408 }
 409
 410 static void
 411 ovsdb_jsonrpc_session_wait(struct ovsdb_jsonrpc_session *s)
 412 {
 413     jsonrpc_session_wait(s->js);
 414     if (!jsonrpc_session_get_backlog(s->js)) {
 415         jsonrpc_session_recv_wait(s->js);
 416     }
 417 }
 418
 419 static void
 420 ovsdb_jsonrpc_session_wait_all(struct ovsdb_jsonrpc_remote *remote)
 421 {
 422     struct ovsdb_jsonrpc_session *s;
 423
 424     LIST_FOR_EACH (s, node, &remote->sessions) {
 425         ovsdb_jsonrpc_session_wait(s);
 426     }
 427 }
 428
 429 static void
 430 ovsdb_jsonrpc_session_close_all(struct ovsdb_jsonrpc_remote *remote)
 431 {
 432     struct ovsdb_jsonrpc_session *s, *next;
 433
 434     LIST_FOR_EACH_SAFE (s, next, node, &remote->sessions) {
 435         ovsdb_jsonrpc_session_close(s);
 436     }
 437 }
 438
 439 /* Forces all of the JSON-RPC sessions managed by 'remote' to disconnect and
 440  * reconnect. */
 441 static void
 442 ovsdb_jsonrpc_session_reconnect_all(struct ovsdb_jsonrpc_remote *remote)
 443 {
 444     struct ovsdb_jsonrpc_session *s, *next;
 445
 446     LIST_FOR_EACH_SAFE (s, next, node, &remote->sessions) {
 447         jsonrpc_session_force_reconnect(s->js);
 448         if (!jsonrpc_session_is_alive(s->js)) {
 449             ovsdb_jsonrpc_session_close(s);
 450         }
 451     }
 452 }
 453
 454 /* Sets the options for all of the JSON-RPC sessions managed by 'remote' to
 455  * 'options'. */
 456 static void
 457 ovsdb_jsonrpc_session_set_all_options(
 458     struct ovsdb_jsonrpc_remote *remote,
 459     const struct ovsdb_jsonrpc_options *options)
 460 {
 461     struct ovsdb_jsonrpc_session *s;
 462
 463     LIST_FOR_EACH (s, node, &remote->sessions) {
 464         ovsdb_jsonrpc_session_set_options(s, options);
 465     }
 466 }
 467
 468 static bool
 469 ovsdb_jsonrpc_session_get_status(const struct ovsdb_jsonrpc_remote *remote,
 470                                  struct ovsdb_jsonrpc_remote_status *status)
 471 {
 472     const struct ovsdb_jsonrpc_session *s;
 473     const struct jsonrpc_session *js;
 474     struct ovsdb_lock_waiter *waiter;
 475     struct reconnect_stats rstats;
 476     struct ds locks_held, locks_waiting, locks_lost;
 477
 478     if (list_is_empty(&remote->sessions)) {
 479         return false;
 480     }
 481     s = CONTAINER_OF(remote->sessions.next, struct ovsdb_jsonrpc_session, node);
 482     js = s->js;
 483
 484     status->is_connected = jsonrpc_session_is_connected(js);
 485     status->last_error = jsonrpc_session_get_status(js);
 486
 487     jsonrpc_session_get_reconnect_stats(js, &rstats);
 488     status->state = rstats.state;
 489     status->sec_since_connect = rstats.msec_since_connect == UINT_MAX
 490         ? UINT_MAX : rstats.msec_since_connect / 1000;
 491     status->sec_since_disconnect = rstats.msec_since_disconnect == UINT_MAX
 492         ? UINT_MAX : rstats.msec_since_disconnect / 1000;
 493
 494     ds_init(&locks_held);
 495     ds_init(&locks_waiting);
 496     ds_init(&locks_lost);
 497     HMAP_FOR_EACH (waiter, session_node, &s->up.waiters) {
 498         struct ds *string;
 499
 500         string = (ovsdb_lock_waiter_is_owner(waiter) ? &locks_held
 501                   : waiter->mode == OVSDB_LOCK_WAIT ? &locks_waiting
 502                   : &locks_lost);
 503         if (string->length) {
 504             ds_put_char(string, ' ');
 505         }
 506         ds_put_cstr(string, waiter->lock_name);
 507     }
 508     status->locks_held = ds_steal_cstr(&locks_held);
 509     status->locks_waiting = ds_steal_cstr(&locks_waiting);
 510     status->locks_lost = ds_steal_cstr(&locks_lost);
 511
 512     status->n_connections = list_size(&remote->sessions);
 513
 514     return true;
 515 }
 516
 517 static const char *
 518 get_db_name(const struct ovsdb_jsonrpc_session *s)
 519 {
 520     return s->remote->server->up.db->schema->name;
 521 }
 522
 523 static struct jsonrpc_msg *
 524 ovsdb_jsonrpc_check_db_name(const struct ovsdb_jsonrpc_session *s,
 525                             const struct jsonrpc_msg *request)
 526 {
 527     struct json_array *params;
 528     const char *want_db_name;
 529     const char *have_db_name;
 530     struct ovsdb_error *error;
 531     struct jsonrpc_msg *reply;
 532
 533     params = json_array(request->params);
 534     if (!params->n || params->elems[0]->type != JSON_STRING) {
 535         error = ovsdb_syntax_error(
 536             request->params, NULL,
 537             "%s request params must begin with <db-name>", request->method);
 538         goto error;
 539     }
 540
 541     want_db_name = params->elems[0]->u.string;
 542     have_db_name = get_db_name(s);
 543     if (strcmp(want_db_name, have_db_name)) {
 544         error = ovsdb_syntax_error(
 545             request->params, "unknown database",
 546             "%s request specifies unknown database %s",
 547             request->method, want_db_name);
 548         goto error;
 549     }
 550
 551     return NULL;
 552
 553 error:
 554     reply = jsonrpc_create_reply(ovsdb_error_to_json(error), request->id);
 555     ovsdb_error_destroy(error);
 556     return reply;
 557 }
 558
 559 static struct ovsdb_error *
 560 ovsdb_jsonrpc_session_parse_lock_name(const struct jsonrpc_msg *request,
 561                                       const char **lock_namep)
 562 {
 563     const struct json_array *params;
 564
 565     params = json_array(request->params);
 566     if (params->n != 1 || params->elems[0]->type != JSON_STRING ||
 567         !ovsdb_parser_is_id(json_string(params->elems[0]))) {
 568         *lock_namep = NULL;
 569         return ovsdb_syntax_error(request->params, NULL,
 570                                   "%s request params must be <id>",
 571                                   request->method);
 572     }
 573
 574     *lock_namep = json_string(params->elems[0]);
 575     return NULL;
 576 }
 577
 578 static void
 579 ovsdb_jsonrpc_session_notify(struct ovsdb_session *session,
 580                              const char *lock_name,
 581                              const char *method)
 582 {
 583     struct ovsdb_jsonrpc_session *s;
 584     struct json *params;
 585
 586     s = CONTAINER_OF(session, struct ovsdb_jsonrpc_session, up);
 587     params = json_array_create_1(json_string_create(lock_name));
 588     jsonrpc_session_send(s->js, jsonrpc_create_notify(method, params));
 589 }
 590
 591 static struct jsonrpc_msg *
 592 ovsdb_jsonrpc_session_lock(struct ovsdb_jsonrpc_session *s,
 593                            struct jsonrpc_msg *request,
 594                            enum ovsdb_lock_mode mode)
 595 {
 596     struct ovsdb_lock_waiter *waiter;
 597     struct jsonrpc_msg *reply;
 598     struct ovsdb_error *error;
 599     struct ovsdb_session *victim;
 600     const char *lock_name;
 601     struct json *result;
 602
 603     error = ovsdb_jsonrpc_session_parse_lock_name(request, &lock_name);
 604     if (error) {
 605         goto error;
 606     }
 607
 608     /* Report error if this session has issued a "lock" or "steal" without a
 609      * matching "unlock" for this lock. */
 610     waiter = ovsdb_session_get_lock_waiter(&s->up, lock_name);
 611     if (waiter) {
 612         error = ovsdb_syntax_error(
 613             request->params, NULL,
 614             "must issue \"unlock\" before new \"%s\"", request->method);
 615         goto error;
 616     }
 617
 618     /* Get the lock, add us as a waiter. */
 619     waiter = ovsdb_server_lock(&s->remote->server->up, &s->up, lock_name, mode,
 620                                &victim);
 621     if (victim) {
 622         ovsdb_jsonrpc_session_notify(victim, lock_name, "stolen");
 623     }
 624
 625     result = json_object_create();
 626     json_object_put(result, "locked",
 627                     json_boolean_create(ovsdb_lock_waiter_is_owner(waiter)));
 628
 629     return jsonrpc_create_reply(result, request->id);
 630
 631 error:
 632     reply = jsonrpc_create_reply(ovsdb_error_to_json(error), request->id);
 633     ovsdb_error_destroy(error);
 634     return reply;
 635 }
 636
 637 static void
 638 ovsdb_jsonrpc_session_unlock_all(struct ovsdb_jsonrpc_session *s)
 639 {
 640     struct ovsdb_lock_waiter *waiter, *next;
 641
 642     HMAP_FOR_EACH_SAFE (waiter, next, session_node, &s->up.waiters) {
 643         ovsdb_jsonrpc_session_unlock__(waiter);
 644     }
 645 }
 646
 647 static void
 648 ovsdb_jsonrpc_session_unlock__(struct ovsdb_lock_waiter *waiter)
 649 {
 650     struct ovsdb_lock *lock = waiter->lock;
 651
 652     if (lock) {
 653         struct ovsdb_session *new_owner = ovsdb_lock_waiter_remove(waiter);
 654         if (new_owner) {
 655             ovsdb_jsonrpc_session_notify(new_owner, lock->name, "locked");
 656         } else {
 657             /* ovsdb_server_lock() might have freed 'lock'. */
 658         }
 659     }
 660
 661     ovsdb_lock_waiter_destroy(waiter);
 662 }
 663
 664 static struct jsonrpc_msg *
 665 ovsdb_jsonrpc_session_unlock(struct ovsdb_jsonrpc_session *s,
 666                              struct jsonrpc_msg *request)
 667 {
 668     struct ovsdb_lock_waiter *waiter;
 669     struct jsonrpc_msg *reply;
 670     struct ovsdb_error *error;
 671     const char *lock_name;
 672
 673     error = ovsdb_jsonrpc_session_parse_lock_name(request, &lock_name);
 674     if (error) {
 675         goto error;
 676     }
 677
 678     /* Report error if this session has not issued a "lock" or "steal" for this
 679      * lock. */
 680     waiter = ovsdb_session_get_lock_waiter(&s->up, lock_name);
 681     if (!waiter) {
 682         error = ovsdb_syntax_error(
 683             request->params, NULL, "\"unlock\" without \"lock\" or \"steal\"");
 684         goto error;
 685     }
 686
 687     ovsdb_jsonrpc_session_unlock__(waiter);
 688
 689     return jsonrpc_create_reply(json_object_create(), request->id);
 690
 691 error:
 692     reply = jsonrpc_create_reply(ovsdb_error_to_json(error), request->id);
 693     ovsdb_error_destroy(error);
 694     return reply;
 695 }
 696
 697 static struct jsonrpc_msg *
 698 execute_transaction(struct ovsdb_jsonrpc_session *s,
 699                     struct jsonrpc_msg *request)
 700 {
 701     ovsdb_jsonrpc_trigger_create(s, request->id, request->params);
 702     request->id = NULL;
 703     request->params = NULL;
 704     jsonrpc_msg_destroy(request);
 705     return NULL;
 706 }
 707
 708 static void
 709 ovsdb_jsonrpc_session_got_request(struct ovsdb_jsonrpc_session *s,
 710                                   struct jsonrpc_msg *request)
 711 {
 712     struct jsonrpc_msg *reply;
 713
 714     if (!strcmp(request->method, "transact")) {
 715         reply = ovsdb_jsonrpc_check_db_name(s, request);
 716         if (!reply) {
 717             reply = execute_transaction(s, request);
 718         }
 719     } else if (!strcmp(request->method, "monitor")) {
 720         reply = ovsdb_jsonrpc_check_db_name(s, request);
 721         if (!reply) {
 722             reply = jsonrpc_create_reply(
 723                 ovsdb_jsonrpc_monitor_create(s, request->params), request->id);
 724         }
 725     } else if (!strcmp(request->method, "monitor_cancel")) {
 726         reply = ovsdb_jsonrpc_monitor_cancel(s, json_array(request->params),
 727                                              request->id);
 728     } else if (!strcmp(request->method, "get_schema")) {
 729         reply = ovsdb_jsonrpc_check_db_name(s, request);
 730         if (!reply) {
 731             reply = jsonrpc_create_reply(
 732                 ovsdb_schema_to_json(s->remote->server->up.db->schema),
 733                 request->id);
 734         }
 735     } else if (!strcmp(request->method, "list_dbs")) {
 736         reply = jsonrpc_create_reply(
 737             json_array_create_1(json_string_create(get_db_name(s))),
 738             request->id);
 739     } else if (!strcmp(request->method, "lock")) {
 740         reply = ovsdb_jsonrpc_session_lock(s, request, OVSDB_LOCK_WAIT);
 741     } else if (!strcmp(request->method, "steal")) {
 742         reply = ovsdb_jsonrpc_session_lock(s, request, OVSDB_LOCK_STEAL);
 743     } else if (!strcmp(request->method, "unlock")) {
 744         reply = ovsdb_jsonrpc_session_unlock(s, request);
 745     } else if (!strcmp(request->method, "echo")) {
 746         reply = jsonrpc_create_reply(json_clone(request->params), request->id);
 747     } else {
 748         reply = jsonrpc_create_error(json_string_create("unknown method"),
 749                                      request->id);
 750     }
 751
 752     if (reply) {
 753         jsonrpc_msg_destroy(request);
 754         jsonrpc_session_send(s->js, reply);
 755     }
 756 }
 757
 758 static void
 759 execute_cancel(struct ovsdb_jsonrpc_session *s, struct jsonrpc_msg *request)
 760 {
 761     if (json_array(request->params)->n == 1) {
 762         struct ovsdb_jsonrpc_trigger *t;
 763         struct json *id;
 764
 765         id = request->params->u.array.elems[0];
 766         t = ovsdb_jsonrpc_trigger_find(s, id, json_hash(id, 0));
 767         if (t) {
 768             ovsdb_jsonrpc_trigger_complete(t);
 769         }
 770     }
 771 }
 772
 773 static void
 774 ovsdb_jsonrpc_session_got_notify(struct ovsdb_jsonrpc_session *s,
 775                                  struct jsonrpc_msg *request)
 776 {
 777     if (!strcmp(request->method, "cancel")) {
 778         execute_cancel(s, request);
 779     }
 780     jsonrpc_msg_destroy(request);
 781 }
 782 \f
 783 /* JSON-RPC database server triggers.
 784  *
 785  * (Every transaction is treated as a trigger even if it doesn't actually have
 786  * any "wait" operations.) */
 787
 788 struct ovsdb_jsonrpc_trigger {
 789     struct ovsdb_trigger trigger;
 790     struct hmap_node hmap_node; /* In session's "triggers" hmap. */
 791     struct json *id;
 792 };
 793
 794 static void
 795 ovsdb_jsonrpc_trigger_create(struct ovsdb_jsonrpc_session *s,
 796                              struct json *id, struct json *params)
 797 {
 798     struct ovsdb_jsonrpc_trigger *t;
 799     size_t hash;
 800
 801     /* Check for duplicate ID. */
 802     hash = json_hash(id, 0);
 803     t = ovsdb_jsonrpc_trigger_find(s, id, hash);
 804     if (t) {
 805         struct jsonrpc_msg *msg;
 806
 807         msg = jsonrpc_create_error(json_string_create("duplicate request ID"),
 808                                    id);
 809         jsonrpc_session_send(s->js, msg);
 810         json_destroy(id);
 811         json_destroy(params);
 812         return;
 813     }
 814
 815     /* Insert into trigger table. */
 816     t = xmalloc(sizeof *t);
 817     ovsdb_trigger_init(&s->up, &t->trigger, params, time_msec());
 818     t->id = id;
 819     hmap_insert(&s->triggers, &t->hmap_node, hash);
 820
 821     /* Complete early if possible. */
 822     if (ovsdb_trigger_is_complete(&t->trigger)) {
 823         ovsdb_jsonrpc_trigger_complete(t);
 824     }
 825 }
 826
 827 static struct ovsdb_jsonrpc_trigger *
 828 ovsdb_jsonrpc_trigger_find(struct ovsdb_jsonrpc_session *s,
 829                            const struct json *id, size_t hash)
 830 {
 831     struct ovsdb_jsonrpc_trigger *t;
 832
 833     HMAP_FOR_EACH_WITH_HASH (t, hmap_node, hash, &s->triggers) {
 834         if (json_equal(t->id, id)) {
 835             return t;
 836         }
 837     }
 838
 839     return NULL;
 840 }
 841
 842 static void
 843 ovsdb_jsonrpc_trigger_complete(struct ovsdb_jsonrpc_trigger *t)
 844 {
 845     struct ovsdb_jsonrpc_session *s;
 846
 847     s = CONTAINER_OF(t->trigger.session, struct ovsdb_jsonrpc_session, up);
 848
 849     if (jsonrpc_session_is_connected(s->js)) {
 850         struct jsonrpc_msg *reply;
 851         struct json *result;
 852
 853         result = ovsdb_trigger_steal_result(&t->trigger);
 854         if (result) {
 855             reply = jsonrpc_create_reply(result, t->id);
 856         } else {
 857             reply = jsonrpc_create_error(json_string_create("canceled"),
 858                                          t->id);
 859         }
 860         jsonrpc_session_send(s->js, reply);
 861     }
 862
 863     json_destroy(t->id);
 864     ovsdb_trigger_destroy(&t->trigger);
 865     hmap_remove(&s->triggers, &t->hmap_node);
 866     free(t);
 867 }
 868
 869 static void
 870 ovsdb_jsonrpc_trigger_complete_all(struct ovsdb_jsonrpc_session *s)
 871 {
 872     struct ovsdb_jsonrpc_trigger *t, *next;
 873     HMAP_FOR_EACH_SAFE (t, next, hmap_node, &s->triggers) {
 874         ovsdb_jsonrpc_trigger_complete(t);
 875     }
 876 }
 877
 878 static void
 879 ovsdb_jsonrpc_trigger_complete_done(struct ovsdb_jsonrpc_session *s)
 880 {
 881     while (!list_is_empty(&s->up.completions)) {
 882         struct ovsdb_jsonrpc_trigger *t
 883             = CONTAINER_OF(s->up.completions.next,
 884                            struct ovsdb_jsonrpc_trigger, trigger.node);
 885         ovsdb_jsonrpc_trigger_complete(t);
 886     }
 887 }
 888 \f
 889 /* JSON-RPC database table monitors. */
 890
 891 enum ovsdb_jsonrpc_monitor_selection {
 892     OJMS_INITIAL = 1 << 0,      /* All rows when monitor is created. */
 893     OJMS_INSERT = 1 << 1,       /* New rows. */
 894     OJMS_DELETE = 1 << 2,       /* Deleted rows. */
 895     OJMS_MODIFY = 1 << 3        /* Modified rows. */
 896 };
 897
 898 /* A particular column being monitored. */
 899 struct ovsdb_jsonrpc_monitor_column {
 900     const struct ovsdb_column *column;
 901     enum ovsdb_jsonrpc_monitor_selection select;
 902 };
 903
 904 /* A particular table being monitored. */
 905 struct ovsdb_jsonrpc_monitor_table {
 906     const struct ovsdb_table *table;
 907
 908     /* This is the union (bitwise-OR) of the 'select' values in all of the
 909      * members of 'columns' below. */
 910     enum ovsdb_jsonrpc_monitor_selection select;
 911
 912     /* Columns being monitored. */
 913     struct ovsdb_jsonrpc_monitor_column *columns;
 914     size_t n_columns;
 915 };
 916
 917 /* A collection of tables being monitored. */
 918 struct ovsdb_jsonrpc_monitor {
 919     struct ovsdb_replica replica;
 920     struct ovsdb_jsonrpc_session *session;
 921     struct hmap_node node;      /* In ovsdb_jsonrpc_session's "monitors". */
 922
 923     struct json *monitor_id;
 924     struct shash tables;     /* Holds "struct ovsdb_jsonrpc_monitor_table"s. */
 925 };
 926
 927 static const struct ovsdb_replica_class ovsdb_jsonrpc_replica_class;
 928
 929 struct ovsdb_jsonrpc_monitor *ovsdb_jsonrpc_monitor_find(
 930     struct ovsdb_jsonrpc_session *, const struct json *monitor_id);
 931 static void ovsdb_jsonrpc_monitor_destroy(struct ovsdb_replica *);
 932 static struct json *ovsdb_jsonrpc_monitor_get_initial(
 933     const struct ovsdb_jsonrpc_monitor *);
 934
 935 static bool
 936 parse_bool(struct ovsdb_parser *parser, const char *name, bool default_value)
 937 {
 938     const struct json *json;
 939
 940     json = ovsdb_parser_member(parser, name, OP_BOOLEAN | OP_OPTIONAL);
 941     return json ? json_boolean(json) : default_value;
 942 }
 943
 944 struct ovsdb_jsonrpc_monitor *
 945 ovsdb_jsonrpc_monitor_find(struct ovsdb_jsonrpc_session *s,
 946                            const struct json *monitor_id)
 947 {
 948     struct ovsdb_jsonrpc_monitor *m;
 949
 950     HMAP_FOR_EACH_WITH_HASH (m, node, json_hash(monitor_id, 0), &s->monitors) {
 951         if (json_equal(m->monitor_id, monitor_id)) {
 952             return m;
 953         }
 954     }
 955
 956     return NULL;
 957 }
 958
 959 static void
 960 ovsdb_jsonrpc_add_monitor_column(struct ovsdb_jsonrpc_monitor_table *mt,
 961                                  const struct ovsdb_column *column,
 962                                  enum ovsdb_jsonrpc_monitor_selection select,
 963                                  size_t *allocated_columns)
 964 {
 965     struct ovsdb_jsonrpc_monitor_column *c;
 966
 967     if (mt->n_columns >= *allocated_columns) {
 968         mt->columns = x2nrealloc(mt->columns, allocated_columns,
 969                                  sizeof *mt->columns);
 970     }
 971
 972     c = &mt->columns[mt->n_columns++];
 973     c->column = column;
 974     c->select = select;
 975 }
 976
 977 static int
 978 compare_ovsdb_jsonrpc_monitor_column(const void *a_, const void *b_)
 979 {
 980     const struct ovsdb_jsonrpc_monitor_column *a = a_;
 981     const struct ovsdb_jsonrpc_monitor_column *b = b_;
 982
 983     return a->column < b->column ? -1 : a->column > b->column;
 984 }
 985
 986 static struct ovsdb_error * WARN_UNUSED_RESULT
 987 ovsdb_jsonrpc_parse_monitor_request(struct ovsdb_jsonrpc_monitor_table *mt,
 988                                     const struct json *monitor_request,
 989                                     size_t *allocated_columns)
 990 {
 991     const struct ovsdb_table_schema *ts = mt->table->schema;
 992     enum ovsdb_jsonrpc_monitor_selection select;
 993     const struct json *columns, *select_json;
 994     struct ovsdb_parser parser;
 995     struct ovsdb_error *error;
 996
 997     ovsdb_parser_init(&parser, monitor_request, "table %s", ts->name);
 998     columns = ovsdb_parser_member(&parser, "columns", OP_ARRAY | OP_OPTIONAL);
 999     select_json = ovsdb_parser_member(&parser, "select",
1000                                       OP_OBJECT | OP_OPTIONAL);
1001     error = ovsdb_parser_finish(&parser);
1002     if (error) {
1003         return error;
1004     }
1005
1006     if (select_json) {
1007         select = 0;
1008         ovsdb_parser_init(&parser, select_json, "table %s select", ts->name);
1009         if (parse_bool(&parser, "initial", true)) {
1010             select |= OJMS_INITIAL;
1011         }
1012         if (parse_bool(&parser, "insert", true)) {
1013             select |= OJMS_INSERT;
1014         }
1015         if (parse_bool(&parser, "delete", true)) {
1016             select |= OJMS_DELETE;
1017         }
1018         if (parse_bool(&parser, "modify", true)) {
1019             select |= OJMS_MODIFY;
1020         }
1021         error = ovsdb_parser_finish(&parser);
1022         if (error) {
1023             return error;
1024         }
1025     } else {
1026         select = OJMS_INITIAL | OJMS_INSERT | OJMS_DELETE | OJMS_MODIFY;
1027     }
1028     mt->select |= select;
1029
1030     if (columns) {
1031         size_t i;
1032
1033         if (columns->type != JSON_ARRAY) {
1034             return ovsdb_syntax_error(columns, NULL,
1035                                       "array of column names expected");
1036         }
1037
1038         for (i = 0; i < columns->u.array.n; i++) {
1039             const struct ovsdb_column *column;
1040             const char *s;
1041
1042             if (columns->u.array.elems[i]->type != JSON_STRING) {
1043                 return ovsdb_syntax_error(columns, NULL,
1044                                           "array of column names expected");
1045             }
1046
1047             s = columns->u.array.elems[i]->u.string;
1048             column = shash_find_data(&mt->table->schema->columns, s);
1049             if (!column) {
1050                 return ovsdb_syntax_error(columns, NULL, "%s is not a valid "
1051                                           "column name", s);
1052             }
1053             ovsdb_jsonrpc_add_monitor_column(mt, column, select,
1054                                              allocated_columns);
1055         }
1056     } else {
1057         struct shash_node *node;
1058
1059         SHASH_FOR_EACH (node, &ts->columns) {
1060             const struct ovsdb_column *column = node->data;
1061             if (column->index != OVSDB_COL_UUID) {
1062                 ovsdb_jsonrpc_add_monitor_column(mt, column, select,
1063                                                  allocated_columns);
1064             }
1065         }
1066     }
1067
1068     return NULL;
1069 }
1070
1071 static struct json *
1072 ovsdb_jsonrpc_monitor_create(struct ovsdb_jsonrpc_session *s,
1073                              struct json *params)
1074 {
1075     struct ovsdb_jsonrpc_monitor *m = NULL;
1076     struct json *monitor_id, *monitor_requests;
1077     struct ovsdb_error *error = NULL;
1078     struct shash_node *node;
1079     struct json *json;
1080
1081     if (json_array(params)->n != 3) {
1082         error = ovsdb_syntax_error(params, NULL, "invalid parameters");
1083         goto error;
1084     }
1085     monitor_id = params->u.array.elems[1];
1086     monitor_requests = params->u.array.elems[2];
1087     if (monitor_requests->type != JSON_OBJECT) {
1088         error = ovsdb_syntax_error(monitor_requests, NULL,
1089                                    "monitor-requests must be object");
1090         goto error;
1091     }
1092
1093     if (ovsdb_jsonrpc_monitor_find(s, monitor_id)) {
1094         error = ovsdb_syntax_error(monitor_id, NULL, "duplicate monitor ID");
1095         goto error;
1096     }
1097
1098     m = xzalloc(sizeof *m);
1099     ovsdb_replica_init(&m->replica, &ovsdb_jsonrpc_replica_class);
1100     ovsdb_add_replica(s->remote->server->up.db, &m->replica);
1101     m->session = s;
1102     hmap_insert(&s->monitors, &m->node, json_hash(monitor_id, 0));
1103     m->monitor_id = json_clone(monitor_id);
1104     shash_init(&m->tables);
1105
1106     SHASH_FOR_EACH (node, json_object(monitor_requests)) {
1107         const struct ovsdb_table *table;
1108         struct ovsdb_jsonrpc_monitor_table *mt;
1109         size_t allocated_columns;
1110         const struct json *mr_value;
1111         size_t i;
1112
1113         table = ovsdb_get_table(s->remote->server->up.db, node->name);
1114         if (!table) {
1115             error = ovsdb_syntax_error(NULL, NULL,
1116                                        "no table named %s", node->name);
1117             goto error;
1118         }
1119
1120         mt = xzalloc(sizeof *mt);
1121         mt->table = table;
1122         shash_add(&m->tables, table->schema->name, mt);
1123
1124         /* Parse columns. */
1125         mr_value = node->data;
1126         allocated_columns = 0;
1127         if (mr_value->type == JSON_ARRAY) {
1128             const struct json_array *array = &mr_value->u.array;
1129
1130             for (i = 0; i < array->n; i++) {
1131                 error = ovsdb_jsonrpc_parse_monitor_request(
1132                     mt, array->elems[i], &allocated_columns);
1133                 if (error) {
1134                     goto error;
1135                 }
1136             }
1137         } else {
1138             error = ovsdb_jsonrpc_parse_monitor_request(
1139                 mt, mr_value, &allocated_columns);
1140             if (error) {
1141                 goto error;
1142             }
1143         }
1144
1145         /* Check for duplicate columns. */
1146         qsort(mt->columns, mt->n_columns, sizeof *mt->columns,
1147               compare_ovsdb_jsonrpc_monitor_column);
1148         for (i = 1; i < mt->n_columns; i++) {
1149             if (mt->columns[i].column == mt->columns[i - 1].column) {
1150                 error = ovsdb_syntax_error(mr_value, NULL, "column %s "
1151                                            "mentioned more than once",
1152                                            mt->columns[i].column->name);
1153                 goto error;
1154             }
1155         }
1156     }
1157
1158     return ovsdb_jsonrpc_monitor_get_initial(m);
1159
1160 error:
1161     if (m) {
1162         ovsdb_remove_replica(s->remote->server->up.db, &m->replica);
1163     }
1164
1165     json = ovsdb_error_to_json(error);
1166     ovsdb_error_destroy(error);
1167     return json;
1168 }
1169
1170 static struct jsonrpc_msg *
1171 ovsdb_jsonrpc_monitor_cancel(struct ovsdb_jsonrpc_session *s,
1172                              struct json_array *params,
1173                              const struct json *request_id)
1174 {
1175     if (params->n != 1) {
1176         return jsonrpc_create_error(json_string_create("invalid parameters"),
1177                                     request_id);
1178     } else {
1179         struct ovsdb_jsonrpc_monitor *m;
1180
1181         m = ovsdb_jsonrpc_monitor_find(s, params->elems[0]);
1182         if (!m) {
1183             return jsonrpc_create_error(json_string_create("unknown monitor"),
1184                                         request_id);
1185         } else {
1186             ovsdb_remove_replica(s->remote->server->up.db, &m->replica);
1187             return jsonrpc_create_reply(json_object_create(), request_id);
1188         }
1189     }
1190 }
1191
1192 static void
1193 ovsdb_jsonrpc_monitor_remove_all(struct ovsdb_jsonrpc_session *s)
1194 {
1195     struct ovsdb_jsonrpc_monitor *m, *next;
1196
1197     HMAP_FOR_EACH_SAFE (m, next, node, &s->monitors) {
1198         ovsdb_remove_replica(s->remote->server->up.db, &m->replica);
1199     }
1200 }
1201
1202 static struct ovsdb_jsonrpc_monitor *
1203 ovsdb_jsonrpc_monitor_cast(struct ovsdb_replica *replica)
1204 {
1205     assert(replica->class == &ovsdb_jsonrpc_replica_class);
1206     return CONTAINER_OF(replica, struct ovsdb_jsonrpc_monitor, replica);
1207 }
1208
1209 struct ovsdb_jsonrpc_monitor_aux {
1210     bool initial;               /* Sending initial contents of table? */
1211     const struct ovsdb_jsonrpc_monitor *monitor;
1212     struct json *json;          /* JSON for the whole transaction. */
1213
1214     /* Current table.  */
1215     struct ovsdb_jsonrpc_monitor_table *mt;
1216     struct json *table_json;    /* JSON for table's transaction. */
1217 };
1218
1219 static bool
1220 any_reportable_change(const struct ovsdb_jsonrpc_monitor_table *mt,
1221                       const unsigned long int *changed)
1222 {
1223     size_t i;
1224
1225     for (i = 0; i < mt->n_columns; i++) {
1226         const struct ovsdb_jsonrpc_monitor_column *c = &mt->columns[i];
1227         unsigned int idx = c->column->index;
1228
1229         if (c->select & OJMS_MODIFY && bitmap_is_set(changed, idx)) {
1230             return true;
1231         }
1232     }
1233
1234     return false;
1235 }
1236
1237 static bool
1238 ovsdb_jsonrpc_monitor_change_cb(const struct ovsdb_row *old,
1239                                 const struct ovsdb_row *new,
1240                                 const unsigned long int *changed,
1241                                 void *aux_)
1242 {
1243     struct ovsdb_jsonrpc_monitor_aux *aux = aux_;
1244     const struct ovsdb_jsonrpc_monitor *m = aux->monitor;
1245     struct ovsdb_table *table = new ? new->table : old->table;
1246     enum ovsdb_jsonrpc_monitor_selection type;
1247     struct json *old_json, *new_json;
1248     struct json *row_json;
1249     char uuid[UUID_LEN + 1];
1250     size_t i;
1251
1252     if (!aux->mt || table != aux->mt->table) {
1253         aux->mt = shash_find_data(&m->tables, table->schema->name);
1254         aux->table_json = NULL;
1255         if (!aux->mt) {
1256             /* We don't care about rows in this table at all.  Tell the caller
1257              * to skip it.  */
1258             return false;
1259         }
1260     }
1261
1262     type = (aux->initial ? OJMS_INITIAL
1263             : !old ? OJMS_INSERT
1264             : !new ? OJMS_DELETE
1265             : OJMS_MODIFY);
1266     if (!(aux->mt->select & type)) {
1267         /* We don't care about this type of change (but do want to be called
1268          * back for changes to other rows in the same table). */
1269         return true;
1270     }
1271
1272     if (type == OJMS_MODIFY && !any_reportable_change(aux->mt, changed)) {
1273         /* Nothing of interest changed. */
1274         return true;
1275     }
1276
1277     old_json = new_json = NULL;
1278     if (type & (OJMS_DELETE | OJMS_MODIFY)) {
1279         old_json = json_object_create();
1280     }
1281     if (type & (OJMS_INITIAL | OJMS_INSERT | OJMS_MODIFY)) {
1282         new_json = json_object_create();
1283     }
1284     for (i = 0; i < aux->mt->n_columns; i++) {
1285         const struct ovsdb_jsonrpc_monitor_column *c = &aux->mt->columns[i];
1286         const struct ovsdb_column *column = c->column;
1287         unsigned int idx = c->column->index;
1288
1289         if (!(type & c->select)) {
1290             /* We don't care about this type of change for this particular
1291              * column (but we will care about it for some other column). */
1292             continue;
1293         }
1294
1295         if ((type == OJMS_MODIFY && bitmap_is_set(changed, idx))
1296             || type == OJMS_DELETE) {
1297             json_object_put(old_json, column->name,
1298                             ovsdb_datum_to_json(&old->fields[idx],
1299                                                 &column->type));
1300         }
1301         if (type & (OJMS_INITIAL | OJMS_INSERT | OJMS_MODIFY)) {
1302             json_object_put(new_json, column->name,
1303                             ovsdb_datum_to_json(&new->fields[idx],
1304                                                 &column->type));
1305         }
1306     }
1307
1308     /* Create JSON object for transaction overall. */
1309     if (!aux->json) {
1310         aux->json = json_object_create();
1311     }
1312
1313     /* Create JSON object for transaction on this table. */
1314     if (!aux->table_json) {
1315         aux->table_json = json_object_create();
1316         json_object_put(aux->json, aux->mt->table->schema->name,
1317                         aux->table_json);
1318     }
1319
1320     /* Create JSON object for transaction on this row. */
1321     row_json = json_object_create();
1322     if (old_json) {
1323         json_object_put(row_json, "old", old_json);
1324     }
1325     if (new_json) {
1326         json_object_put(row_json, "new", new_json);
1327     }
1328
1329     /* Add JSON row to JSON table. */
1330     snprintf(uuid, sizeof uuid,
1331              UUID_FMT, UUID_ARGS(ovsdb_row_get_uuid(new ? new : old)));
1332     json_object_put(aux->table_json, uuid, row_json);
1333
1334     return true;
1335 }
1336
1337 static void
1338 ovsdb_jsonrpc_monitor_init_aux(struct ovsdb_jsonrpc_monitor_aux *aux,
1339                                const struct ovsdb_jsonrpc_monitor *m,
1340                                bool initial)
1341 {
1342     aux->initial = initial;
1343     aux->monitor = m;
1344     aux->json = NULL;
1345     aux->mt = NULL;
1346     aux->table_json = NULL;
1347 }
1348
1349 static struct ovsdb_error *
1350 ovsdb_jsonrpc_monitor_commit(struct ovsdb_replica *replica,
1351                              const struct ovsdb_txn *txn,
1352                              bool durable OVS_UNUSED)
1353 {
1354     struct ovsdb_jsonrpc_monitor *m = ovsdb_jsonrpc_monitor_cast(replica);
1355     struct ovsdb_jsonrpc_monitor_aux aux;
1356
1357     ovsdb_jsonrpc_monitor_init_aux(&aux, m, false);
1358     ovsdb_txn_for_each_change(txn, ovsdb_jsonrpc_monitor_change_cb, &aux);
1359     if (aux.json) {
1360         struct jsonrpc_msg *msg;
1361         struct json *params;
1362
1363         params = json_array_create_2(json_clone(aux.monitor->monitor_id),
1364                                      aux.json);
1365         msg = jsonrpc_create_notify("update", params);
1366         jsonrpc_session_send(aux.monitor->session->js, msg);
1367     }
1368
1369     return NULL;
1370 }
1371
1372 static struct json *
1373 ovsdb_jsonrpc_monitor_get_initial(const struct ovsdb_jsonrpc_monitor *m)
1374 {
1375     struct ovsdb_jsonrpc_monitor_aux aux;
1376     struct shash_node *node;
1377
1378     ovsdb_jsonrpc_monitor_init_aux(&aux, m, true);
1379     SHASH_FOR_EACH (node, &m->tables) {
1380         struct ovsdb_jsonrpc_monitor_table *mt = node->data;
1381
1382         if (mt->select & OJMS_INITIAL) {
1383             struct ovsdb_row *row;
1384
1385             HMAP_FOR_EACH (row, hmap_node, &mt->table->rows) {
1386                 ovsdb_jsonrpc_monitor_change_cb(NULL, row, NULL, &aux);
1387             }
1388         }
1389     }
1390     return aux.json ? aux.json : json_object_create();
1391 }
1392
1393 static void
1394 ovsdb_jsonrpc_monitor_destroy(struct ovsdb_replica *replica)
1395 {
1396     struct ovsdb_jsonrpc_monitor *m = ovsdb_jsonrpc_monitor_cast(replica);
1397     struct shash_node *node;
1398
1399     json_destroy(m->monitor_id);
1400     SHASH_FOR_EACH (node, &m->tables) {
1401         struct ovsdb_jsonrpc_monitor_table *mt = node->data;
1402         free(mt->columns);
1403         free(mt);
1404     }
1405     shash_destroy(&m->tables);
1406     hmap_remove(&m->session->monitors, &m->node);
1407     free(m);
1408 }
1409
1410 static const struct ovsdb_replica_class ovsdb_jsonrpc_replica_class = {
1411     ovsdb_jsonrpc_monitor_commit,
1412     ovsdb_jsonrpc_monitor_destroy
1413 };