ovsdb/jsonrpc-server.c

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