ovsdb/jsonrpc-server.c

   1 /* Copyright (c) 2009, 2010 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 "json.h"
  26 #include "jsonrpc.h"
  27 #include "ovsdb-error.h"
  28 #include "ovsdb-parser.h"
  29 #include "ovsdb.h"
  30 #include "reconnect.h"
  31 #include "row.h"
  32 #include "stream.h"
  33 #include "table.h"
  34 #include "timeval.h"
  35 #include "transaction.h"
  36 #include "trigger.h"
  37 #include "vlog.h"
  38
  39 VLOG_DEFINE_THIS_MODULE(ovsdb_jsonrpc_server);
  40
  41 struct ovsdb_jsonrpc_remote;
  42 struct ovsdb_jsonrpc_session;
  43
  44 /* Message rate-limiting. */
  45 struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
  46
  47 /* Sessions. */
  48 static struct ovsdb_jsonrpc_session *ovsdb_jsonrpc_session_create(
  49     struct ovsdb_jsonrpc_remote *, struct jsonrpc_session *);
  50 static void ovsdb_jsonrpc_session_run_all(struct ovsdb_jsonrpc_remote *);
  51 static void ovsdb_jsonrpc_session_wait_all(struct ovsdb_jsonrpc_remote *);
  52 static void ovsdb_jsonrpc_session_close_all(struct ovsdb_jsonrpc_remote *);
  53 static void ovsdb_jsonrpc_session_reconnect_all(struct ovsdb_jsonrpc_remote *);
  54 static void ovsdb_jsonrpc_session_set_all_options(
  55     struct ovsdb_jsonrpc_remote *, const struct ovsdb_jsonrpc_options *);
  56
  57 /* Triggers. */
  58 static void ovsdb_jsonrpc_trigger_create(struct ovsdb_jsonrpc_session *,
  59                                          struct json *id, struct json *params);
  60 static struct ovsdb_jsonrpc_trigger *ovsdb_jsonrpc_trigger_find(
  61     struct ovsdb_jsonrpc_session *, const struct json *id, size_t hash);
  62 static void ovsdb_jsonrpc_trigger_complete(struct ovsdb_jsonrpc_trigger *);
  63 static void ovsdb_jsonrpc_trigger_complete_all(struct ovsdb_jsonrpc_session *);
  64 static void ovsdb_jsonrpc_trigger_complete_done(
  65     struct ovsdb_jsonrpc_session *);
  66
  67 /* Monitors. */
  68 static struct json *ovsdb_jsonrpc_monitor_create(
  69     struct ovsdb_jsonrpc_session *, struct json *params);
  70 static struct jsonrpc_msg *ovsdb_jsonrpc_monitor_cancel(
  71     struct ovsdb_jsonrpc_session *,
  72     struct json_array *params,
  73     const struct json *request_id);
  74 static void ovsdb_jsonrpc_monitor_remove_all(struct ovsdb_jsonrpc_session *);
  75 \f
  76 /* JSON-RPC database server. */
  77
  78 struct ovsdb_jsonrpc_server {
  79     struct ovsdb *db;
  80     unsigned int n_sessions, max_sessions;
  81     struct shash remotes;      /* Contains "struct ovsdb_jsonrpc_remote *"s. */
  82 };
  83
  84 /* A configured remote.  This is either a passive stream listener plus a list
  85  * of the currently connected sessions, or a list of exactly one active
  86  * session. */
  87 struct ovsdb_jsonrpc_remote {
  88     struct ovsdb_jsonrpc_server *server;
  89     struct pstream *listener;   /* Listener, if passive. */
  90     struct list sessions;       /* List of "struct ovsdb_jsonrpc_session"s. */
  91 };
  92
  93 static struct ovsdb_jsonrpc_remote *ovsdb_jsonrpc_server_add_remote(
  94     struct ovsdb_jsonrpc_server *, const char *name);
  95 static void ovsdb_jsonrpc_server_del_remote(struct shash_node *);
  96
  97 struct ovsdb_jsonrpc_server *
  98 ovsdb_jsonrpc_server_create(struct ovsdb *db)
  99 {
 100     struct ovsdb_jsonrpc_server *server = xzalloc(sizeof *server);
 101     server->db = db;
 102     server->max_sessions = 64;
 103     shash_init(&server->remotes);
 104     return server;
 105 }
 106
 107 void
 108 ovsdb_jsonrpc_server_destroy(struct ovsdb_jsonrpc_server *svr)
 109 {
 110     struct shash_node *node, *next;
 111
 112     SHASH_FOR_EACH_SAFE (node, next, &svr->remotes) {
 113         ovsdb_jsonrpc_server_del_remote(node);
 114     }
 115     shash_destroy(&svr->remotes);
 116     free(svr);
 117 }
 118
 119 struct ovsdb_jsonrpc_options *
 120 ovsdb_jsonrpc_default_options(void)
 121 {
 122     struct ovsdb_jsonrpc_options *options = xzalloc(sizeof *options);
 123     options->probe_interval = RECONNECT_DEFAULT_PROBE_INTERVAL;
 124     options->max_backoff = RECONNECT_DEFAULT_MAX_BACKOFF;
 125     return options;
 126 }
 127
 128 /* Sets 'svr''s current set of remotes to the names in 'new_remotes', with
 129  * options in the struct ovsdb_jsonrpc_options supplied as the data values.
 130  *
 131  * A remote is an active or passive stream connection method, e.g. "pssl:" or
 132  * "tcp:1.2.3.4". */
 133 void
 134 ovsdb_jsonrpc_server_set_remotes(struct ovsdb_jsonrpc_server *svr,
 135                                  const struct shash *new_remotes)
 136 {
 137     struct shash_node *node, *next;
 138
 139     SHASH_FOR_EACH_SAFE (node, next, &svr->remotes) {
 140         if (!shash_find(new_remotes, node->name)) {
 141             ovsdb_jsonrpc_server_del_remote(node);
 142         }
 143     }
 144     SHASH_FOR_EACH (node, new_remotes) {
 145         const struct ovsdb_jsonrpc_options *options = node->data;
 146         struct ovsdb_jsonrpc_remote *remote;
 147
 148         remote = shash_find_data(&svr->remotes, node->name);
 149         if (!remote) {
 150             remote = ovsdb_jsonrpc_server_add_remote(svr, node->name);
 151             if (!remote) {
 152                 continue;
 153             }
 154         }
 155
 156         ovsdb_jsonrpc_session_set_all_options(remote, options);
 157     }
 158 }
 159
 160 static struct ovsdb_jsonrpc_remote *
 161 ovsdb_jsonrpc_server_add_remote(struct ovsdb_jsonrpc_server *svr,
 162                                 const char *name)
 163 {
 164     struct ovsdb_jsonrpc_remote *remote;
 165     struct pstream *listener;
 166     int error;
 167
 168     error = jsonrpc_pstream_open(name, &listener);
 169     if (error && error != EAFNOSUPPORT) {
 170         VLOG_ERR_RL(&rl, "%s: listen failed: %s", name, strerror(error));
 171         return NULL;
 172     }
 173
 174     remote = xmalloc(sizeof *remote);
 175     remote->server = svr;
 176     remote->listener = listener;
 177     list_init(&remote->sessions);
 178     shash_add(&svr->remotes, name, remote);
 179
 180     if (!listener) {
 181         ovsdb_jsonrpc_session_create(remote, jsonrpc_session_open(name));
 182     }
 183     return remote;
 184 }
 185
 186 static void
 187 ovsdb_jsonrpc_server_del_remote(struct shash_node *node)
 188 {
 189     struct ovsdb_jsonrpc_remote *remote = node->data;
 190
 191     ovsdb_jsonrpc_session_close_all(remote);
 192     pstream_close(remote->listener);
 193     shash_delete(&remote->server->remotes, node);
 194     free(remote);
 195 }
 196
 197 /* Forces all of the JSON-RPC sessions managed by 'svr' to disconnect and
 198  * reconnect. */
 199 void
 200 ovsdb_jsonrpc_server_reconnect(struct ovsdb_jsonrpc_server *svr)
 201 {
 202     struct shash_node *node;
 203
 204     SHASH_FOR_EACH (node, &svr->remotes) {
 205         struct ovsdb_jsonrpc_remote *remote = node->data;
 206
 207         ovsdb_jsonrpc_session_reconnect_all(remote);
 208     }
 209 }
 210
 211 void
 212 ovsdb_jsonrpc_server_run(struct ovsdb_jsonrpc_server *svr)
 213 {
 214     struct shash_node *node;
 215
 216     SHASH_FOR_EACH (node, &svr->remotes) {
 217         struct ovsdb_jsonrpc_remote *remote = node->data;
 218
 219         if (remote->listener && svr->n_sessions < svr->max_sessions) {
 220             struct stream *stream;
 221             int error;
 222
 223             error = pstream_accept(remote->listener, &stream);
 224             if (!error) {
 225                 struct jsonrpc_session *js;
 226                 js = jsonrpc_session_open_unreliably(jsonrpc_open(stream));
 227                 ovsdb_jsonrpc_session_create(remote, js);
 228             } else if (error != EAGAIN) {
 229                 VLOG_WARN_RL(&rl, "%s: accept failed: %s",
 230                              pstream_get_name(remote->listener),
 231                              strerror(error));
 232             }
 233         }
 234
 235         ovsdb_jsonrpc_session_run_all(remote);
 236     }
 237 }
 238
 239 void
 240 ovsdb_jsonrpc_server_wait(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         if (remote->listener && svr->n_sessions < svr->max_sessions) {
 248             pstream_wait(remote->listener);
 249         }
 250
 251         ovsdb_jsonrpc_session_wait_all(remote);
 252     }
 253 }
 254 \f
 255 /* JSON-RPC database server session. */
 256
 257 struct ovsdb_jsonrpc_session {
 258     struct ovsdb_jsonrpc_remote *remote;
 259     struct list node;           /* Element in remote's sessions list. */
 260
 261     /* Triggers. */
 262     struct hmap triggers;       /* Hmap of "struct ovsdb_jsonrpc_trigger"s. */
 263     struct list completions;    /* Completed triggers. */
 264
 265     /* Monitors. */
 266     struct hmap monitors;       /* Hmap of "struct ovsdb_jsonrpc_monitor"s. */
 267
 268     /* Network connectivity. */
 269     struct jsonrpc_session *js;  /* JSON-RPC session. */
 270     unsigned int js_seqno;       /* Last jsonrpc_session_get_seqno() value. */
 271 };
 272
 273 static void ovsdb_jsonrpc_session_close(struct ovsdb_jsonrpc_session *);
 274 static int ovsdb_jsonrpc_session_run(struct ovsdb_jsonrpc_session *);
 275 static void ovsdb_jsonrpc_session_wait(struct ovsdb_jsonrpc_session *);
 276 static void ovsdb_jsonrpc_session_set_options(
 277     struct ovsdb_jsonrpc_session *, const struct ovsdb_jsonrpc_options *);
 278 static void ovsdb_jsonrpc_session_got_request(struct ovsdb_jsonrpc_session *,
 279                                              struct jsonrpc_msg *);
 280 static void ovsdb_jsonrpc_session_got_notify(struct ovsdb_jsonrpc_session *,
 281                                              struct jsonrpc_msg *);
 282
 283 static struct ovsdb_jsonrpc_session *
 284 ovsdb_jsonrpc_session_create(struct ovsdb_jsonrpc_remote *remote,
 285                              struct jsonrpc_session *js)
 286 {
 287     struct ovsdb_jsonrpc_session *s;
 288
 289     s = xzalloc(sizeof *s);
 290     s->remote = remote;
 291     list_push_back(&remote->sessions, &s->node);
 292     hmap_init(&s->triggers);
 293     hmap_init(&s->monitors);
 294     list_init(&s->completions);
 295     s->js = js;
 296     s->js_seqno = jsonrpc_session_get_seqno(js);
 297
 298     remote->server->n_sessions++;
 299
 300     return s;
 301 }
 302
 303 static void
 304 ovsdb_jsonrpc_session_close(struct ovsdb_jsonrpc_session *s)
 305 {
 306     ovsdb_jsonrpc_monitor_remove_all(s);
 307     jsonrpc_session_close(s->js);
 308     list_remove(&s->node);
 309     s->remote->server->n_sessions--;
 310     free(s);
 311 }
 312
 313 static int
 314 ovsdb_jsonrpc_session_run(struct ovsdb_jsonrpc_session *s)
 315 {
 316     jsonrpc_session_run(s->js);
 317     if (s->js_seqno != jsonrpc_session_get_seqno(s->js)) {
 318         s->js_seqno = jsonrpc_session_get_seqno(s->js);
 319         ovsdb_jsonrpc_trigger_complete_all(s);
 320         ovsdb_jsonrpc_monitor_remove_all(s);
 321     }
 322
 323     ovsdb_jsonrpc_trigger_complete_done(s);
 324
 325     if (!jsonrpc_session_get_backlog(s->js)) {
 326         struct jsonrpc_msg *msg = jsonrpc_session_recv(s->js);
 327         if (msg) {
 328             if (msg->type == JSONRPC_REQUEST) {
 329                 ovsdb_jsonrpc_session_got_request(s, msg);
 330             } else if (msg->type == JSONRPC_NOTIFY) {
 331                 ovsdb_jsonrpc_session_got_notify(s, msg);
 332             } else {
 333                 VLOG_WARN("%s: received unexpected %s message",
 334                           jsonrpc_session_get_name(s->js),
 335                           jsonrpc_msg_type_to_string(msg->type));
 336                 jsonrpc_session_force_reconnect(s->js);
 337                 jsonrpc_msg_destroy(msg);
 338             }
 339         }
 340     }
 341     return jsonrpc_session_is_alive(s->js) ? 0 : ETIMEDOUT;
 342 }
 343
 344 static void
 345 ovsdb_jsonrpc_session_set_options(struct ovsdb_jsonrpc_session *session,
 346                                   const struct ovsdb_jsonrpc_options *options)
 347 {
 348     jsonrpc_session_set_max_backoff(session->js, options->max_backoff);
 349     jsonrpc_session_set_probe_interval(session->js, options->probe_interval);
 350 }
 351
 352 static void
 353 ovsdb_jsonrpc_session_run_all(struct ovsdb_jsonrpc_remote *remote)
 354 {
 355     struct ovsdb_jsonrpc_session *s, *next;
 356
 357     LIST_FOR_EACH_SAFE (s, next, node, &remote->sessions) {
 358         int error = ovsdb_jsonrpc_session_run(s);
 359         if (error) {
 360             ovsdb_jsonrpc_session_close(s);
 361         }
 362     }
 363 }
 364
 365 static void
 366 ovsdb_jsonrpc_session_wait(struct ovsdb_jsonrpc_session *s)
 367 {
 368     jsonrpc_session_wait(s->js);
 369     if (!jsonrpc_session_get_backlog(s->js)) {
 370         jsonrpc_session_recv_wait(s->js);
 371     }
 372 }
 373
 374 static void
 375 ovsdb_jsonrpc_session_wait_all(struct ovsdb_jsonrpc_remote *remote)
 376 {
 377     struct ovsdb_jsonrpc_session *s;
 378
 379     LIST_FOR_EACH (s, node, &remote->sessions) {
 380         ovsdb_jsonrpc_session_wait(s);
 381     }
 382 }
 383
 384 static void
 385 ovsdb_jsonrpc_session_close_all(struct ovsdb_jsonrpc_remote *remote)
 386 {
 387     struct ovsdb_jsonrpc_session *s, *next;
 388
 389     LIST_FOR_EACH_SAFE (s, next, node, &remote->sessions) {
 390         ovsdb_jsonrpc_session_close(s);
 391     }
 392 }
 393
 394 /* Forces all of the JSON-RPC sessions managed by 'remote' to disconnect and
 395  * reconnect. */
 396 static void
 397 ovsdb_jsonrpc_session_reconnect_all(struct ovsdb_jsonrpc_remote *remote)
 398 {
 399     struct ovsdb_jsonrpc_session *s, *next;
 400
 401     LIST_FOR_EACH_SAFE (s, next, node, &remote->sessions) {
 402         jsonrpc_session_force_reconnect(s->js);
 403         if (!jsonrpc_session_is_alive(s->js)) {
 404             ovsdb_jsonrpc_session_close(s);
 405         }
 406     }
 407 }
 408
 409 /* Sets the options for all of the JSON-RPC sessions managed by 'remote' to
 410  * 'options'. */
 411 static void
 412 ovsdb_jsonrpc_session_set_all_options(
 413     struct ovsdb_jsonrpc_remote *remote,
 414     const struct ovsdb_jsonrpc_options *options)
 415 {
 416     struct ovsdb_jsonrpc_session *s;
 417
 418     LIST_FOR_EACH (s, node, &remote->sessions) {
 419         ovsdb_jsonrpc_session_set_options(s, options);
 420     }
 421 }
 422
 423 static const char *
 424 get_db_name(const struct ovsdb_jsonrpc_session *s)
 425 {
 426     return s->remote->server->db->schema->name;
 427 }
 428
 429 static struct jsonrpc_msg *
 430 ovsdb_jsonrpc_check_db_name(const struct ovsdb_jsonrpc_session *s,
 431                             const struct jsonrpc_msg *request)
 432 {
 433     struct json_array *params;
 434     const char *want_db_name;
 435     const char *have_db_name;
 436     struct ovsdb_error *error;
 437     struct jsonrpc_msg *reply;
 438
 439     params = json_array(request->params);
 440     if (!params->n || params->elems[0]->type != JSON_STRING) {
 441         error = ovsdb_syntax_error(
 442             request->params, NULL,
 443             "%s request params must begin with <db-name>", request->method);
 444         goto error;
 445     }
 446
 447     want_db_name = params->elems[0]->u.string;
 448     have_db_name = get_db_name(s);
 449     if (strcmp(want_db_name, have_db_name)) {
 450         error = ovsdb_syntax_error(
 451             request->params, "unknown database",
 452             "%s request specifies unknown database %s",
 453             request->method, want_db_name);
 454         goto error;
 455     }
 456
 457     return NULL;
 458
 459 error:
 460     reply = jsonrpc_create_reply(ovsdb_error_to_json(error), request->id);
 461     ovsdb_error_destroy(error);
 462     return reply;
 463 }
 464
 465 static struct jsonrpc_msg *
 466 execute_transaction(struct ovsdb_jsonrpc_session *s,
 467                     struct jsonrpc_msg *request)
 468 {
 469     ovsdb_jsonrpc_trigger_create(s, request->id, request->params);
 470     request->id = NULL;
 471     request->params = NULL;
 472     jsonrpc_msg_destroy(request);
 473     return NULL;
 474 }
 475
 476 static void
 477 ovsdb_jsonrpc_session_got_request(struct ovsdb_jsonrpc_session *s,
 478                                   struct jsonrpc_msg *request)
 479 {
 480     struct jsonrpc_msg *reply;
 481
 482     if (!strcmp(request->method, "transact")) {
 483         reply = ovsdb_jsonrpc_check_db_name(s, request);
 484         if (!reply) {
 485             reply = execute_transaction(s, request);
 486         }
 487     } else if (!strcmp(request->method, "monitor")) {
 488         reply = ovsdb_jsonrpc_check_db_name(s, request);
 489         if (!reply) {
 490             reply = jsonrpc_create_reply(
 491                 ovsdb_jsonrpc_monitor_create(s, request->params), request->id);
 492         }
 493     } else if (!strcmp(request->method, "monitor_cancel")) {
 494         reply = ovsdb_jsonrpc_monitor_cancel(s, json_array(request->params),
 495                                              request->id);
 496     } else if (!strcmp(request->method, "get_schema")) {
 497         reply = ovsdb_jsonrpc_check_db_name(s, request);
 498         if (!reply) {
 499             reply = jsonrpc_create_reply(
 500                 ovsdb_schema_to_json(s->remote->server->db->schema),
 501                 request->id);
 502         }
 503     } else if (!strcmp(request->method, "list_dbs")) {
 504         reply = jsonrpc_create_reply(
 505             json_array_create_1(json_string_create(get_db_name(s))),
 506             request->id);
 507     } else if (!strcmp(request->method, "echo")) {
 508         reply = jsonrpc_create_reply(json_clone(request->params), request->id);
 509     } else {
 510         reply = jsonrpc_create_error(json_string_create("unknown method"),
 511                                      request->id);
 512     }
 513
 514     if (reply) {
 515         jsonrpc_msg_destroy(request);
 516         jsonrpc_session_send(s->js, reply);
 517     }
 518 }
 519
 520 static void
 521 execute_cancel(struct ovsdb_jsonrpc_session *s, struct jsonrpc_msg *request)
 522 {
 523     if (json_array(request->params)->n == 1) {
 524         struct ovsdb_jsonrpc_trigger *t;
 525         struct json *id;
 526
 527         id = request->params->u.array.elems[0];
 528         t = ovsdb_jsonrpc_trigger_find(s, id, json_hash(id, 0));
 529         if (t) {
 530             ovsdb_jsonrpc_trigger_complete(t);
 531         }
 532     }
 533 }
 534
 535 static void
 536 ovsdb_jsonrpc_session_got_notify(struct ovsdb_jsonrpc_session *s,
 537                                  struct jsonrpc_msg *request)
 538 {
 539     if (!strcmp(request->method, "cancel")) {
 540         execute_cancel(s, request);
 541     }
 542     jsonrpc_msg_destroy(request);
 543 }
 544 \f
 545 /* JSON-RPC database server triggers.
 546  *
 547  * (Every transaction is treated as a trigger even if it doesn't actually have
 548  * any "wait" operations.) */
 549
 550 struct ovsdb_jsonrpc_trigger {
 551     struct ovsdb_trigger trigger;
 552     struct ovsdb_jsonrpc_session *session;
 553     struct hmap_node hmap_node; /* In session's "triggers" hmap. */
 554     struct json *id;
 555 };
 556
 557 static void
 558 ovsdb_jsonrpc_trigger_create(struct ovsdb_jsonrpc_session *s,
 559                              struct json *id, struct json *params)
 560 {
 561     struct ovsdb_jsonrpc_trigger *t;
 562     size_t hash;
 563
 564     /* Check for duplicate ID. */
 565     hash = json_hash(id, 0);
 566     t = ovsdb_jsonrpc_trigger_find(s, id, hash);
 567     if (t) {
 568         struct jsonrpc_msg *msg;
 569
 570         msg = jsonrpc_create_error(json_string_create("duplicate request ID"),
 571                                    id);
 572         jsonrpc_session_send(s->js, msg);
 573         json_destroy(id);
 574         json_destroy(params);
 575         return;
 576     }
 577
 578     /* Insert into trigger table. */
 579     t = xmalloc(sizeof *t);
 580     ovsdb_trigger_init(s->remote->server->db,
 581                        &t->trigger, params, &s->completions,
 582                        time_msec());
 583     t->session = s;
 584     t->id = id;
 585     hmap_insert(&s->triggers, &t->hmap_node, hash);
 586
 587     /* Complete early if possible. */
 588     if (ovsdb_trigger_is_complete(&t->trigger)) {
 589         ovsdb_jsonrpc_trigger_complete(t);
 590     }
 591 }
 592
 593 static struct ovsdb_jsonrpc_trigger *
 594 ovsdb_jsonrpc_trigger_find(struct ovsdb_jsonrpc_session *s,
 595                            const struct json *id, size_t hash)
 596 {
 597     struct ovsdb_jsonrpc_trigger *t;
 598
 599     HMAP_FOR_EACH_WITH_HASH (t, hmap_node, hash, &s->triggers) {
 600         if (json_equal(t->id, id)) {
 601             return t;
 602         }
 603     }
 604
 605     return NULL;
 606 }
 607
 608 static void
 609 ovsdb_jsonrpc_trigger_complete(struct ovsdb_jsonrpc_trigger *t)
 610 {
 611     struct ovsdb_jsonrpc_session *s = t->session;
 612
 613     if (jsonrpc_session_is_connected(s->js)) {
 614         struct jsonrpc_msg *reply;
 615         struct json *result;
 616
 617         result = ovsdb_trigger_steal_result(&t->trigger);
 618         if (result) {
 619             reply = jsonrpc_create_reply(result, t->id);
 620         } else {
 621             reply = jsonrpc_create_error(json_string_create("canceled"),
 622                                          t->id);
 623         }
 624         jsonrpc_session_send(s->js, reply);
 625     }
 626
 627     json_destroy(t->id);
 628     ovsdb_trigger_destroy(&t->trigger);
 629     hmap_remove(&s->triggers, &t->hmap_node);
 630     free(t);
 631 }
 632
 633 static void
 634 ovsdb_jsonrpc_trigger_complete_all(struct ovsdb_jsonrpc_session *s)
 635 {
 636     struct ovsdb_jsonrpc_trigger *t, *next;
 637     HMAP_FOR_EACH_SAFE (t, next, hmap_node, &s->triggers) {
 638         ovsdb_jsonrpc_trigger_complete(t);
 639     }
 640 }
 641
 642 static void
 643 ovsdb_jsonrpc_trigger_complete_done(struct ovsdb_jsonrpc_session *s)
 644 {
 645     while (!list_is_empty(&s->completions)) {
 646         struct ovsdb_jsonrpc_trigger *t
 647             = CONTAINER_OF(s->completions.next,
 648                            struct ovsdb_jsonrpc_trigger, trigger.node);
 649         ovsdb_jsonrpc_trigger_complete(t);
 650     }
 651 }
 652 \f
 653 /* JSON-RPC database table monitors. */
 654
 655 enum ovsdb_jsonrpc_monitor_selection {
 656     OJMS_INITIAL = 1 << 0,      /* All rows when monitor is created. */
 657     OJMS_INSERT = 1 << 1,       /* New rows. */
 658     OJMS_DELETE = 1 << 2,       /* Deleted rows. */
 659     OJMS_MODIFY = 1 << 3        /* Modified rows. */
 660 };
 661
 662 /* A particular column being monitored. */
 663 struct ovsdb_jsonrpc_monitor_column {
 664     const struct ovsdb_column *column;
 665     enum ovsdb_jsonrpc_monitor_selection select;
 666 };
 667
 668 /* A particular table being monitored. */
 669 struct ovsdb_jsonrpc_monitor_table {
 670     const struct ovsdb_table *table;
 671
 672     /* This is the union (bitwise-OR) of the 'select' values in all of the
 673      * members of 'columns' below. */
 674     enum ovsdb_jsonrpc_monitor_selection select;
 675
 676     /* Columns being monitored. */
 677     struct ovsdb_jsonrpc_monitor_column *columns;
 678     size_t n_columns;
 679 };
 680
 681 /* A collection of tables being monitored. */
 682 struct ovsdb_jsonrpc_monitor {
 683     struct ovsdb_replica replica;
 684     struct ovsdb_jsonrpc_session *session;
 685     struct hmap_node node;      /* In ovsdb_jsonrpc_session's "monitors". */
 686
 687     struct json *monitor_id;
 688     struct shash tables;     /* Holds "struct ovsdb_jsonrpc_monitor_table"s. */
 689 };
 690
 691 static const struct ovsdb_replica_class ovsdb_jsonrpc_replica_class;
 692
 693 struct ovsdb_jsonrpc_monitor *ovsdb_jsonrpc_monitor_find(
 694     struct ovsdb_jsonrpc_session *, const struct json *monitor_id);
 695 static void ovsdb_jsonrpc_monitor_destroy(struct ovsdb_replica *);
 696 static struct json *ovsdb_jsonrpc_monitor_get_initial(
 697     const struct ovsdb_jsonrpc_monitor *);
 698
 699 static bool
 700 parse_bool(struct ovsdb_parser *parser, const char *name, bool default_value)
 701 {
 702     const struct json *json;
 703
 704     json = ovsdb_parser_member(parser, name, OP_BOOLEAN | OP_OPTIONAL);
 705     return json ? json_boolean(json) : default_value;
 706 }
 707
 708 struct ovsdb_jsonrpc_monitor *
 709 ovsdb_jsonrpc_monitor_find(struct ovsdb_jsonrpc_session *s,
 710                            const struct json *monitor_id)
 711 {
 712     struct ovsdb_jsonrpc_monitor *m;
 713
 714     HMAP_FOR_EACH_WITH_HASH (m, node, json_hash(monitor_id, 0), &s->monitors) {
 715         if (json_equal(m->monitor_id, monitor_id)) {
 716             return m;
 717         }
 718     }
 719
 720     return NULL;
 721 }
 722
 723 static void
 724 ovsdb_jsonrpc_add_monitor_column(struct ovsdb_jsonrpc_monitor_table *mt,
 725                                  const struct ovsdb_column *column,
 726                                  enum ovsdb_jsonrpc_monitor_selection select,
 727                                  size_t *allocated_columns)
 728 {
 729     struct ovsdb_jsonrpc_monitor_column *c;
 730
 731     if (mt->n_columns >= *allocated_columns) {
 732         mt->columns = x2nrealloc(mt->columns, allocated_columns,
 733                                  sizeof *mt->columns);
 734     }
 735
 736     c = &mt->columns[mt->n_columns++];
 737     c->column = column;
 738     c->select = select;
 739 }
 740
 741 static int
 742 compare_ovsdb_jsonrpc_monitor_column(const void *a_, const void *b_)
 743 {
 744     const struct ovsdb_jsonrpc_monitor_column *a = a_;
 745     const struct ovsdb_jsonrpc_monitor_column *b = b_;
 746
 747     return a->column < b->column ? -1 : a->column > b->column;
 748 }
 749
 750 static struct ovsdb_error * WARN_UNUSED_RESULT
 751 ovsdb_jsonrpc_parse_monitor_request(struct ovsdb_jsonrpc_monitor_table *mt,
 752                                     const struct json *monitor_request,
 753                                     size_t *allocated_columns)
 754 {
 755     const struct ovsdb_table_schema *ts = mt->table->schema;
 756     enum ovsdb_jsonrpc_monitor_selection select;
 757     const struct json *columns, *select_json;
 758     struct ovsdb_parser parser;
 759     struct ovsdb_error *error;
 760
 761     ovsdb_parser_init(&parser, monitor_request, "table %s", ts->name);
 762     columns = ovsdb_parser_member(&parser, "columns", OP_ARRAY | OP_OPTIONAL);
 763     select_json = ovsdb_parser_member(&parser, "select",
 764                                       OP_OBJECT | OP_OPTIONAL);
 765     error = ovsdb_parser_finish(&parser);
 766     if (error) {
 767         return error;
 768     }
 769
 770     if (select_json) {
 771         select = 0;
 772         ovsdb_parser_init(&parser, select_json, "table %s select", ts->name);
 773         if (parse_bool(&parser, "initial", true)) {
 774             select |= OJMS_INITIAL;
 775         }
 776         if (parse_bool(&parser, "insert", true)) {
 777             select |= OJMS_INSERT;
 778         }
 779         if (parse_bool(&parser, "delete", true)) {
 780             select |= OJMS_DELETE;
 781         }
 782         if (parse_bool(&parser, "modify", true)) {
 783             select |= OJMS_MODIFY;
 784         }
 785         error = ovsdb_parser_finish(&parser);
 786         if (error) {
 787             return error;
 788         }
 789     } else {
 790         select = OJMS_INITIAL | OJMS_INSERT | OJMS_DELETE | OJMS_MODIFY;
 791     }
 792     mt->select |= select;
 793
 794     if (columns) {
 795         size_t i;
 796
 797         if (columns->type != JSON_ARRAY) {
 798             return ovsdb_syntax_error(columns, NULL,
 799                                       "array of column names expected");
 800         }
 801
 802         for (i = 0; i < columns->u.array.n; i++) {
 803             const struct ovsdb_column *column;
 804             const char *s;
 805
 806             if (columns->u.array.elems[i]->type != JSON_STRING) {
 807                 return ovsdb_syntax_error(columns, NULL,
 808                                           "array of column names expected");
 809             }
 810
 811             s = columns->u.array.elems[i]->u.string;
 812             column = shash_find_data(&mt->table->schema->columns, s);
 813             if (!column) {
 814                 return ovsdb_syntax_error(columns, NULL, "%s is not a valid "
 815                                           "column name", s);
 816             }
 817             ovsdb_jsonrpc_add_monitor_column(mt, column, select,
 818                                              allocated_columns);
 819         }
 820     } else {
 821         struct shash_node *node;
 822
 823         SHASH_FOR_EACH (node, &ts->columns) {
 824             const struct ovsdb_column *column = node->data;
 825             if (column->index != OVSDB_COL_UUID) {
 826                 ovsdb_jsonrpc_add_monitor_column(mt, column, select,
 827                                                  allocated_columns);
 828             }
 829         }
 830     }
 831
 832     return NULL;
 833 }
 834
 835 static struct json *
 836 ovsdb_jsonrpc_monitor_create(struct ovsdb_jsonrpc_session *s,
 837                              struct json *params)
 838 {
 839     struct ovsdb_jsonrpc_monitor *m = NULL;
 840     struct json *monitor_id, *monitor_requests;
 841     struct ovsdb_error *error = NULL;
 842     struct shash_node *node;
 843     struct json *json;
 844
 845     if (json_array(params)->n != 3) {
 846         error = ovsdb_syntax_error(params, NULL, "invalid parameters");
 847         goto error;
 848     }
 849     monitor_id = params->u.array.elems[1];
 850     monitor_requests = params->u.array.elems[2];
 851     if (monitor_requests->type != JSON_OBJECT) {
 852         error = ovsdb_syntax_error(monitor_requests, NULL,
 853                                    "monitor-requests must be object");
 854         goto error;
 855     }
 856
 857     if (ovsdb_jsonrpc_monitor_find(s, monitor_id)) {
 858         error = ovsdb_syntax_error(monitor_id, NULL, "duplicate monitor ID");
 859         goto error;
 860     }
 861
 862     m = xzalloc(sizeof *m);
 863     ovsdb_replica_init(&m->replica, &ovsdb_jsonrpc_replica_class);
 864     ovsdb_add_replica(s->remote->server->db, &m->replica);
 865     m->session = s;
 866     hmap_insert(&s->monitors, &m->node, json_hash(monitor_id, 0));
 867     m->monitor_id = json_clone(monitor_id);
 868     shash_init(&m->tables);
 869
 870     SHASH_FOR_EACH (node, json_object(monitor_requests)) {
 871         const struct ovsdb_table *table;
 872         struct ovsdb_jsonrpc_monitor_table *mt;
 873         size_t allocated_columns;
 874         const struct json *mr_value;
 875         size_t i;
 876
 877         table = ovsdb_get_table(s->remote->server->db, node->name);
 878         if (!table) {
 879             error = ovsdb_syntax_error(NULL, NULL,
 880                                        "no table named %s", node->name);
 881             goto error;
 882         }
 883
 884         mt = xzalloc(sizeof *mt);
 885         mt->table = table;
 886         shash_add(&m->tables, table->schema->name, mt);
 887
 888         /* Parse columns. */
 889         mr_value = node->data;
 890         allocated_columns = 0;
 891         if (mr_value->type == JSON_ARRAY) {
 892             const struct json_array *array = &mr_value->u.array;
 893
 894             for (i = 0; i < array->n; i++) {
 895                 error = ovsdb_jsonrpc_parse_monitor_request(
 896                     mt, array->elems[i], &allocated_columns);
 897                 if (error) {
 898                     goto error;
 899                 }
 900             }
 901         } else {
 902             error = ovsdb_jsonrpc_parse_monitor_request(
 903                 mt, mr_value, &allocated_columns);
 904             if (error) {
 905                 goto error;
 906             }
 907         }
 908
 909         /* Check for duplicate columns. */
 910         qsort(mt->columns, mt->n_columns, sizeof *mt->columns,
 911               compare_ovsdb_jsonrpc_monitor_column);
 912         for (i = 1; i < mt->n_columns; i++) {
 913             if (mt->columns[i].column == mt->columns[i - 1].column) {
 914                 error = ovsdb_syntax_error(mr_value, NULL, "column %s "
 915                                            "mentioned more than once",
 916                                            mt->columns[i].column->name);
 917                 goto error;
 918             }
 919         }
 920     }
 921
 922     return ovsdb_jsonrpc_monitor_get_initial(m);
 923
 924 error:
 925     if (m) {
 926         ovsdb_remove_replica(s->remote->server->db, &m->replica);
 927     }
 928
 929     json = ovsdb_error_to_json(error);
 930     ovsdb_error_destroy(error);
 931     return json;
 932 }
 933
 934 static struct jsonrpc_msg *
 935 ovsdb_jsonrpc_monitor_cancel(struct ovsdb_jsonrpc_session *s,
 936                              struct json_array *params,
 937                              const struct json *request_id)
 938 {
 939     if (params->n != 1) {
 940         return jsonrpc_create_error(json_string_create("invalid parameters"),
 941                                     request_id);
 942     } else {
 943         struct ovsdb_jsonrpc_monitor *m;
 944
 945         m = ovsdb_jsonrpc_monitor_find(s, params->elems[0]);
 946         if (!m) {
 947             return jsonrpc_create_error(json_string_create("unknown monitor"),
 948                                         request_id);
 949         } else {
 950             ovsdb_remove_replica(s->remote->server->db, &m->replica);
 951             return jsonrpc_create_reply(json_object_create(), request_id);
 952         }
 953     }
 954 }
 955
 956 static void
 957 ovsdb_jsonrpc_monitor_remove_all(struct ovsdb_jsonrpc_session *s)
 958 {
 959     struct ovsdb_jsonrpc_monitor *m, *next;
 960
 961     HMAP_FOR_EACH_SAFE (m, next, node, &s->monitors) {
 962         ovsdb_remove_replica(s->remote->server->db, &m->replica);
 963     }
 964 }
 965
 966 static struct ovsdb_jsonrpc_monitor *
 967 ovsdb_jsonrpc_monitor_cast(struct ovsdb_replica *replica)
 968 {
 969     assert(replica->class == &ovsdb_jsonrpc_replica_class);
 970     return CONTAINER_OF(replica, struct ovsdb_jsonrpc_monitor, replica);
 971 }
 972
 973 struct ovsdb_jsonrpc_monitor_aux {
 974     bool initial;               /* Sending initial contents of table? */
 975     const struct ovsdb_jsonrpc_monitor *monitor;
 976     struct json *json;          /* JSON for the whole transaction. */
 977
 978     /* Current table.  */
 979     struct ovsdb_jsonrpc_monitor_table *mt;
 980     struct json *table_json;    /* JSON for table's transaction. */
 981 };
 982
 983 static bool
 984 any_reportable_change(const struct ovsdb_jsonrpc_monitor_table *mt,
 985                       const unsigned long int *changed)
 986 {
 987     size_t i;
 988
 989     for (i = 0; i < mt->n_columns; i++) {
 990         const struct ovsdb_jsonrpc_monitor_column *c = &mt->columns[i];
 991         unsigned int idx = c->column->index;
 992
 993         if (c->select & OJMS_MODIFY && bitmap_is_set(changed, idx)) {
 994             return true;
 995         }
 996     }
 997
 998     return false;
 999 }
1000
1001 static bool
1002 ovsdb_jsonrpc_monitor_change_cb(const struct ovsdb_row *old,
1003                                 const struct ovsdb_row *new,
1004                                 const unsigned long int *changed,
1005                                 void *aux_)
1006 {
1007     struct ovsdb_jsonrpc_monitor_aux *aux = aux_;
1008     const struct ovsdb_jsonrpc_monitor *m = aux->monitor;
1009     struct ovsdb_table *table = new ? new->table : old->table;
1010     enum ovsdb_jsonrpc_monitor_selection type;
1011     struct json *old_json, *new_json;
1012     struct json *row_json;
1013     char uuid[UUID_LEN + 1];
1014     size_t i;
1015
1016     if (!aux->mt || table != aux->mt->table) {
1017         aux->mt = shash_find_data(&m->tables, table->schema->name);
1018         aux->table_json = NULL;
1019         if (!aux->mt) {
1020             /* We don't care about rows in this table at all.  Tell the caller
1021              * to skip it.  */
1022             return false;
1023         }
1024     }
1025
1026     type = (aux->initial ? OJMS_INITIAL
1027             : !old ? OJMS_INSERT
1028             : !new ? OJMS_DELETE
1029             : OJMS_MODIFY);
1030     if (!(aux->mt->select & type)) {
1031         /* We don't care about this type of change (but do want to be called
1032          * back for changes to other rows in the same table). */
1033         return true;
1034     }
1035
1036     if (type == OJMS_MODIFY && !any_reportable_change(aux->mt, changed)) {
1037         /* Nothing of interest changed. */
1038         return true;
1039     }
1040
1041     old_json = new_json = NULL;
1042     if (type & (OJMS_DELETE | OJMS_MODIFY)) {
1043         old_json = json_object_create();
1044     }
1045     if (type & (OJMS_INITIAL | OJMS_INSERT | OJMS_MODIFY)) {
1046         new_json = json_object_create();
1047     }
1048     for (i = 0; i < aux->mt->n_columns; i++) {
1049         const struct ovsdb_jsonrpc_monitor_column *c = &aux->mt->columns[i];
1050         const struct ovsdb_column *column = c->column;
1051         unsigned int idx = c->column->index;
1052
1053         if (!(type & c->select)) {
1054             /* We don't care about this type of change for this particular
1055              * column (but we will care about it for some other column). */
1056             continue;
1057         }
1058
1059         if ((type == OJMS_MODIFY && bitmap_is_set(changed, idx))
1060             || type == OJMS_DELETE) {
1061             json_object_put(old_json, column->name,
1062                             ovsdb_datum_to_json(&old->fields[idx],
1063                                                 &column->type));
1064         }
1065         if (type & (OJMS_INITIAL | OJMS_INSERT | OJMS_MODIFY)) {
1066             json_object_put(new_json, column->name,
1067                             ovsdb_datum_to_json(&new->fields[idx],
1068                                                 &column->type));
1069         }
1070     }
1071
1072     /* Create JSON object for transaction overall. */
1073     if (!aux->json) {
1074         aux->json = json_object_create();
1075     }
1076
1077     /* Create JSON object for transaction on this table. */
1078     if (!aux->table_json) {
1079         aux->table_json = json_object_create();
1080         json_object_put(aux->json, aux->mt->table->schema->name,
1081                         aux->table_json);
1082     }
1083
1084     /* Create JSON object for transaction on this row. */
1085     row_json = json_object_create();
1086     if (old_json) {
1087         json_object_put(row_json, "old", old_json);
1088     }
1089     if (new_json) {
1090         json_object_put(row_json, "new", new_json);
1091     }
1092
1093     /* Add JSON row to JSON table. */
1094     snprintf(uuid, sizeof uuid,
1095              UUID_FMT, UUID_ARGS(ovsdb_row_get_uuid(new ? new : old)));
1096     json_object_put(aux->table_json, uuid, row_json);
1097
1098     return true;
1099 }
1100
1101 static void
1102 ovsdb_jsonrpc_monitor_init_aux(struct ovsdb_jsonrpc_monitor_aux *aux,
1103                                const struct ovsdb_jsonrpc_monitor *m,
1104                                bool initial)
1105 {
1106     aux->initial = initial;
1107     aux->monitor = m;
1108     aux->json = NULL;
1109     aux->mt = NULL;
1110     aux->table_json = NULL;
1111 }
1112
1113 static struct ovsdb_error *
1114 ovsdb_jsonrpc_monitor_commit(struct ovsdb_replica *replica,
1115                              const struct ovsdb_txn *txn,
1116                              bool durable OVS_UNUSED)
1117 {
1118     struct ovsdb_jsonrpc_monitor *m = ovsdb_jsonrpc_monitor_cast(replica);
1119     struct ovsdb_jsonrpc_monitor_aux aux;
1120
1121     ovsdb_jsonrpc_monitor_init_aux(&aux, m, false);
1122     ovsdb_txn_for_each_change(txn, ovsdb_jsonrpc_monitor_change_cb, &aux);
1123     if (aux.json) {
1124         struct jsonrpc_msg *msg;
1125         struct json *params;
1126
1127         params = json_array_create_2(json_clone(aux.monitor->monitor_id),
1128                                      aux.json);
1129         msg = jsonrpc_create_notify("update", params);
1130         jsonrpc_session_send(aux.monitor->session->js, msg);
1131     }
1132
1133     return NULL;
1134 }
1135
1136 static struct json *
1137 ovsdb_jsonrpc_monitor_get_initial(const struct ovsdb_jsonrpc_monitor *m)
1138 {
1139     struct ovsdb_jsonrpc_monitor_aux aux;
1140     struct shash_node *node;
1141
1142     ovsdb_jsonrpc_monitor_init_aux(&aux, m, true);
1143     SHASH_FOR_EACH (node, &m->tables) {
1144         struct ovsdb_jsonrpc_monitor_table *mt = node->data;
1145
1146         if (mt->select & OJMS_INITIAL) {
1147             struct ovsdb_row *row;
1148
1149             HMAP_FOR_EACH (row, hmap_node, &mt->table->rows) {
1150                 ovsdb_jsonrpc_monitor_change_cb(NULL, row, NULL, &aux);
1151             }
1152         }
1153     }
1154     return aux.json ? aux.json : json_object_create();
1155 }
1156
1157 static void
1158 ovsdb_jsonrpc_monitor_destroy(struct ovsdb_replica *replica)
1159 {
1160     struct ovsdb_jsonrpc_monitor *m = ovsdb_jsonrpc_monitor_cast(replica);
1161     struct shash_node *node;
1162
1163     json_destroy(m->monitor_id);
1164     SHASH_FOR_EACH (node, &m->tables) {
1165         struct ovsdb_jsonrpc_monitor_table *mt = node->data;
1166         free(mt->columns);
1167         free(mt);
1168     }
1169     shash_destroy(&m->tables);
1170     hmap_remove(&m->session->monitors, &m->node);
1171     free(m);
1172 }
1173
1174 static const struct ovsdb_replica_class ovsdb_jsonrpc_replica_class = {
1175     ovsdb_jsonrpc_monitor_commit,
1176     ovsdb_jsonrpc_monitor_destroy
1177 };