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