ovsdb/jsonrpc-server.c

   1 /* Copyright (c) 2009, 2010, 2011, 2012, 2013, 2014 Nicira, Inc.
   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 <errno.h>
  21
  22 #include "bitmap.h"
  23 #include "column.h"
  24 #include "dynamic-string.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 "poll-loop.h"
  31 #include "reconnect.h"
  32 #include "row.h"
  33 #include "server.h"
  34 #include "simap.h"
  35 #include "stream.h"
  36 #include "table.h"
  37 #include "timeval.h"
  38 #include "transaction.h"
  39 #include "trigger.h"
  40 #include "vlog.h"
  41
  42 VLOG_DEFINE_THIS_MODULE(ovsdb_jsonrpc_server);
  43
  44 struct ovsdb_jsonrpc_remote;
  45 struct ovsdb_jsonrpc_session;
  46
  47 /* Message rate-limiting. */
  48 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
  49
  50 /* Sessions. */
  51 static struct ovsdb_jsonrpc_session *ovsdb_jsonrpc_session_create(
  52     struct ovsdb_jsonrpc_remote *, struct jsonrpc_session *);
  53 static void ovsdb_jsonrpc_session_run_all(struct ovsdb_jsonrpc_remote *);
  54 static void ovsdb_jsonrpc_session_wait_all(struct ovsdb_jsonrpc_remote *);
  55 static void ovsdb_jsonrpc_session_get_memory_usage_all(
  56     const struct ovsdb_jsonrpc_remote *, struct simap *usage);
  57 static void ovsdb_jsonrpc_session_close_all(struct ovsdb_jsonrpc_remote *);
  58 static void ovsdb_jsonrpc_session_reconnect_all(struct ovsdb_jsonrpc_remote *);
  59 static void ovsdb_jsonrpc_session_set_all_options(
  60     struct ovsdb_jsonrpc_remote *, const struct ovsdb_jsonrpc_options *);
  61 static bool ovsdb_jsonrpc_session_get_status(
  62     const struct ovsdb_jsonrpc_remote *,
  63     struct ovsdb_jsonrpc_remote_status *);
  64 static void ovsdb_jsonrpc_session_unlock_all(struct ovsdb_jsonrpc_session *);
  65 static void ovsdb_jsonrpc_session_unlock__(struct ovsdb_lock_waiter *);
  66 static void ovsdb_jsonrpc_session_send(struct ovsdb_jsonrpc_session *,
  67                                        struct jsonrpc_msg *);
  68
  69 /* Triggers. */
  70 static void ovsdb_jsonrpc_trigger_create(struct ovsdb_jsonrpc_session *,
  71                                          struct ovsdb *,
  72                                          struct json *id, struct json *params);
  73 static struct ovsdb_jsonrpc_trigger *ovsdb_jsonrpc_trigger_find(
  74     struct ovsdb_jsonrpc_session *, const struct json *id, size_t hash);
  75 static void ovsdb_jsonrpc_trigger_complete(struct ovsdb_jsonrpc_trigger *);
  76 static void ovsdb_jsonrpc_trigger_complete_all(struct ovsdb_jsonrpc_session *);
  77 static void ovsdb_jsonrpc_trigger_complete_done(
  78     struct ovsdb_jsonrpc_session *);
  79
  80 /* Monitors. */
  81 static struct json *ovsdb_jsonrpc_monitor_create(
  82     struct ovsdb_jsonrpc_session *, struct ovsdb *, struct json *params);
  83 static struct jsonrpc_msg *ovsdb_jsonrpc_monitor_cancel(
  84     struct ovsdb_jsonrpc_session *,
  85     struct json_array *params,
  86     const struct json *request_id);
  87 static void ovsdb_jsonrpc_monitor_remove_all(struct ovsdb_jsonrpc_session *);
  88 static void ovsdb_jsonrpc_monitor_flush_all(struct ovsdb_jsonrpc_session *);
  89 static bool ovsdb_jsonrpc_monitor_needs_flush(struct ovsdb_jsonrpc_session *);
  90 \f
  91 /* JSON-RPC database server. */
  92
  93 struct ovsdb_jsonrpc_server {
  94     struct ovsdb_server up;
  95     unsigned int n_sessions, max_sessions;
  96     struct shash remotes;      /* Contains "struct ovsdb_jsonrpc_remote *"s. */
  97 };
  98
  99 /* A configured remote.  This is either a passive stream listener plus a list
 100  * of the currently connected sessions, or a list of exactly one active
 101  * session. */
 102 struct ovsdb_jsonrpc_remote {
 103     struct ovsdb_jsonrpc_server *server;
 104     struct pstream *listener;   /* Listener, if passive. */
 105     struct list sessions;       /* List of "struct ovsdb_jsonrpc_session"s. */
 106     uint8_t dscp;
 107 };
 108
 109 static struct ovsdb_jsonrpc_remote *ovsdb_jsonrpc_server_add_remote(
 110     struct ovsdb_jsonrpc_server *, const char *name,
 111     const struct ovsdb_jsonrpc_options *options
 112 );
 113 static void ovsdb_jsonrpc_server_del_remote(struct shash_node *);
 114
 115 /* Creates and returns a new server to provide JSON-RPC access to an OVSDB.
 116  *
 117  * The caller must call ovsdb_jsonrpc_server_add_db() for each database to
 118  * which 'server' should provide access. */
 119 struct ovsdb_jsonrpc_server *
 120 ovsdb_jsonrpc_server_create(void)
 121 {
 122     struct ovsdb_jsonrpc_server *server = xzalloc(sizeof *server);
 123     ovsdb_server_init(&server->up);
 124     server->max_sessions = 64;
 125     shash_init(&server->remotes);
 126     return server;
 127 }
 128
 129 /* Adds 'db' to the set of databases served out by 'svr'.  Returns true if
 130  * successful, false if 'db''s name is the same as some database already in
 131  * 'server'. */
 132 bool
 133 ovsdb_jsonrpc_server_add_db(struct ovsdb_jsonrpc_server *svr, struct ovsdb *db)
 134 {
 135     /* The OVSDB protocol doesn't have a way to notify a client that a
 136      * database has been added.  If some client tried to use the database
 137      * that we're adding and failed, then forcing it to reconnect seems like
 138      * a reasonable way to make it try again.
 139      *
 140      * If this is too big of a hammer in practice, we could be more selective,
 141      * e.g. disconnect only connections that actually tried to use a database
 142      * with 'db''s name. */
 143     ovsdb_jsonrpc_server_reconnect(svr);
 144
 145     return ovsdb_server_add_db(&svr->up, db);
 146 }
 147
 148 /* Removes 'db' from the set of databases served out by 'svr'.  Returns
 149  * true if successful, false if there is no database associated with 'db'. */
 150 bool
 151 ovsdb_jsonrpc_server_remove_db(struct ovsdb_jsonrpc_server *svr,
 152                                struct ovsdb *db)
 153 {
 154     /* There might be pointers to 'db' from 'svr', such as monitors or
 155      * outstanding transactions.  Disconnect all JSON-RPC connections to avoid
 156      * accesses to freed memory.
 157      *
 158      * If this is too big of a hammer in practice, we could be more selective,
 159      * e.g. disconnect only connections that actually reference 'db'. */
 160     ovsdb_jsonrpc_server_reconnect(svr);
 161
 162     return ovsdb_server_remove_db(&svr->up, db);
 163 }
 164
 165 void
 166 ovsdb_jsonrpc_server_destroy(struct ovsdb_jsonrpc_server *svr)
 167 {
 168     struct shash_node *node, *next;
 169
 170     SHASH_FOR_EACH_SAFE (node, next, &svr->remotes) {
 171         ovsdb_jsonrpc_server_del_remote(node);
 172     }
 173     shash_destroy(&svr->remotes);
 174     ovsdb_server_destroy(&svr->up);
 175     free(svr);
 176 }
 177
 178 struct ovsdb_jsonrpc_options *
 179 ovsdb_jsonrpc_default_options(const char *target)
 180 {
 181     struct ovsdb_jsonrpc_options *options = xzalloc(sizeof *options);
 182     options->max_backoff = RECONNECT_DEFAULT_MAX_BACKOFF;
 183     options->probe_interval = (stream_or_pstream_needs_probes(target)
 184                                ? RECONNECT_DEFAULT_PROBE_INTERVAL
 185                                : 0);
 186     return options;
 187 }
 188
 189 /* Sets 'svr''s current set of remotes to the names in 'new_remotes', with
 190  * options in the struct ovsdb_jsonrpc_options supplied as the data values.
 191  *
 192  * A remote is an active or passive stream connection method, e.g. "pssl:" or
 193  * "tcp:1.2.3.4". */
 194 void
 195 ovsdb_jsonrpc_server_set_remotes(struct ovsdb_jsonrpc_server *svr,
 196                                  const struct shash *new_remotes)
 197 {
 198     struct shash_node *node, *next;
 199
 200     SHASH_FOR_EACH_SAFE (node, next, &svr->remotes) {
 201         if (!shash_find(new_remotes, node->name)) {
 202             VLOG_INFO("%s: remote deconfigured", node->name);
 203             ovsdb_jsonrpc_server_del_remote(node);
 204         }
 205     }
 206     SHASH_FOR_EACH (node, new_remotes) {
 207         const struct ovsdb_jsonrpc_options *options = node->data;
 208         struct ovsdb_jsonrpc_remote *remote;
 209
 210         remote = shash_find_data(&svr->remotes, node->name);
 211         if (!remote) {
 212             remote = ovsdb_jsonrpc_server_add_remote(svr, node->name, options);
 213             if (!remote) {
 214                 continue;
 215             }
 216         }
 217
 218         ovsdb_jsonrpc_session_set_all_options(remote, options);
 219     }
 220 }
 221
 222 static struct ovsdb_jsonrpc_remote *
 223 ovsdb_jsonrpc_server_add_remote(struct ovsdb_jsonrpc_server *svr,
 224                                 const char *name,
 225                                 const struct ovsdb_jsonrpc_options *options)
 226 {
 227     struct ovsdb_jsonrpc_remote *remote;
 228     struct pstream *listener;
 229     int error;
 230
 231     error = jsonrpc_pstream_open(name, &listener, options->dscp);
 232     if (error && error != EAFNOSUPPORT) {
 233         VLOG_ERR_RL(&rl, "%s: listen failed: %s", name, ovs_strerror(error));
 234         return NULL;
 235     }
 236
 237     remote = xmalloc(sizeof *remote);
 238     remote->server = svr;
 239     remote->listener = listener;
 240     list_init(&remote->sessions);
 241     remote->dscp = options->dscp;
 242     shash_add(&svr->remotes, name, remote);
 243
 244     if (!listener) {
 245         ovsdb_jsonrpc_session_create(remote, jsonrpc_session_open(name, true));
 246     }
 247     return remote;
 248 }
 249
 250 static void
 251 ovsdb_jsonrpc_server_del_remote(struct shash_node *node)
 252 {
 253     struct ovsdb_jsonrpc_remote *remote = node->data;
 254
 255     ovsdb_jsonrpc_session_close_all(remote);
 256     pstream_close(remote->listener);
 257     shash_delete(&remote->server->remotes, node);
 258     free(remote);
 259 }
 260
 261 /* Stores status information for the remote named 'target', which should have
 262  * been configured on 'svr' with a call to ovsdb_jsonrpc_server_set_remotes(),
 263  * into '*status'.  On success returns true, on failure (if 'svr' doesn't have
 264  * a remote named 'target' or if that remote is an inbound remote that has no
 265  * active connections) returns false.  On failure, 'status' will be zeroed.
 266  */
 267 bool
 268 ovsdb_jsonrpc_server_get_remote_status(
 269     const struct ovsdb_jsonrpc_server *svr, const char *target,
 270     struct ovsdb_jsonrpc_remote_status *status)
 271 {
 272     const struct ovsdb_jsonrpc_remote *remote;
 273
 274     memset(status, 0, sizeof *status);
 275
 276     remote = shash_find_data(&svr->remotes, target);
 277     return remote && ovsdb_jsonrpc_session_get_status(remote, status);
 278 }
 279
 280 void
 281 ovsdb_jsonrpc_server_free_remote_status(
 282     struct ovsdb_jsonrpc_remote_status *status)
 283 {
 284     free(status->locks_held);
 285     free(status->locks_waiting);
 286     free(status->locks_lost);
 287 }
 288
 289 /* Forces all of the JSON-RPC sessions managed by 'svr' to disconnect and
 290  * reconnect. */
 291 void
 292 ovsdb_jsonrpc_server_reconnect(struct ovsdb_jsonrpc_server *svr)
 293 {
 294     struct shash_node *node;
 295
 296     SHASH_FOR_EACH (node, &svr->remotes) {
 297         struct ovsdb_jsonrpc_remote *remote = node->data;
 298
 299         ovsdb_jsonrpc_session_reconnect_all(remote);
 300     }
 301 }
 302
 303 void
 304 ovsdb_jsonrpc_server_run(struct ovsdb_jsonrpc_server *svr)
 305 {
 306     struct shash_node *node;
 307
 308     SHASH_FOR_EACH (node, &svr->remotes) {
 309         struct ovsdb_jsonrpc_remote *remote = node->data;
 310
 311         if (remote->listener && svr->n_sessions < svr->max_sessions) {
 312             struct stream *stream;
 313             int error;
 314
 315             error = pstream_accept(remote->listener, &stream);
 316             if (!error) {
 317                 struct jsonrpc_session *js;
 318                 js = jsonrpc_session_open_unreliably(jsonrpc_open(stream),
 319                                                      remote->dscp);
 320                 ovsdb_jsonrpc_session_create(remote, js);
 321             } else if (error != EAGAIN) {
 322                 VLOG_WARN_RL(&rl, "%s: accept failed: %s",
 323                              pstream_get_name(remote->listener),
 324                              ovs_strerror(error));
 325             }
 326         }
 327
 328         ovsdb_jsonrpc_session_run_all(remote);
 329     }
 330 }
 331
 332 void
 333 ovsdb_jsonrpc_server_wait(struct ovsdb_jsonrpc_server *svr)
 334 {
 335     struct shash_node *node;
 336
 337     SHASH_FOR_EACH (node, &svr->remotes) {
 338         struct ovsdb_jsonrpc_remote *remote = node->data;
 339
 340         if (remote->listener && svr->n_sessions < svr->max_sessions) {
 341             pstream_wait(remote->listener);
 342         }
 343
 344         ovsdb_jsonrpc_session_wait_all(remote);
 345     }
 346 }
 347
 348 /* Adds some memory usage statistics for 'svr' into 'usage', for use with
 349  * memory_report(). */
 350 void
 351 ovsdb_jsonrpc_server_get_memory_usage(const struct ovsdb_jsonrpc_server *svr,
 352                                       struct simap *usage)
 353 {
 354     struct shash_node *node;
 355
 356     simap_increase(usage, "sessions", svr->n_sessions);
 357     SHASH_FOR_EACH (node, &svr->remotes) {
 358         struct ovsdb_jsonrpc_remote *remote = node->data;
 359
 360         ovsdb_jsonrpc_session_get_memory_usage_all(remote, usage);
 361     }
 362 }
 363 \f
 364 /* JSON-RPC database server session. */
 365
 366 struct ovsdb_jsonrpc_session {
 367     struct list node;           /* Element in remote's sessions list. */
 368     struct ovsdb_session up;
 369     struct ovsdb_jsonrpc_remote *remote;
 370
 371     /* Triggers. */
 372     struct hmap triggers;       /* Hmap of "struct ovsdb_jsonrpc_trigger"s. */
 373
 374     /* Monitors. */
 375     struct hmap monitors;       /* Hmap of "struct ovsdb_jsonrpc_monitor"s. */
 376
 377     /* Network connectivity. */
 378     struct jsonrpc_session *js;  /* JSON-RPC session. */
 379     unsigned int js_seqno;       /* Last jsonrpc_session_get_seqno() value. */
 380 };
 381
 382 static void ovsdb_jsonrpc_session_close(struct ovsdb_jsonrpc_session *);
 383 static int ovsdb_jsonrpc_session_run(struct ovsdb_jsonrpc_session *);
 384 static void ovsdb_jsonrpc_session_wait(struct ovsdb_jsonrpc_session *);
 385 static void ovsdb_jsonrpc_session_get_memory_usage(
 386     const struct ovsdb_jsonrpc_session *, struct simap *usage);
 387 static void ovsdb_jsonrpc_session_set_options(
 388     struct ovsdb_jsonrpc_session *, const struct ovsdb_jsonrpc_options *);
 389 static void ovsdb_jsonrpc_session_got_request(struct ovsdb_jsonrpc_session *,
 390                                              struct jsonrpc_msg *);
 391 static void ovsdb_jsonrpc_session_got_notify(struct ovsdb_jsonrpc_session *,
 392                                              struct jsonrpc_msg *);
 393
 394 static struct ovsdb_jsonrpc_session *
 395 ovsdb_jsonrpc_session_create(struct ovsdb_jsonrpc_remote *remote,
 396                              struct jsonrpc_session *js)
 397 {
 398     struct ovsdb_jsonrpc_session *s;
 399
 400     s = xzalloc(sizeof *s);
 401     ovsdb_session_init(&s->up, &remote->server->up);
 402     s->remote = remote;
 403     list_push_back(&remote->sessions, &s->node);
 404     hmap_init(&s->triggers);
 405     hmap_init(&s->monitors);
 406     s->js = js;
 407     s->js_seqno = jsonrpc_session_get_seqno(js);
 408
 409     remote->server->n_sessions++;
 410
 411     return s;
 412 }
 413
 414 static void
 415 ovsdb_jsonrpc_session_close(struct ovsdb_jsonrpc_session *s)
 416 {
 417     ovsdb_jsonrpc_monitor_remove_all(s);
 418     ovsdb_jsonrpc_session_unlock_all(s);
 419     ovsdb_jsonrpc_trigger_complete_all(s);
 420
 421     hmap_destroy(&s->monitors);
 422     hmap_destroy(&s->triggers);
 423
 424     jsonrpc_session_close(s->js);
 425     list_remove(&s->node);
 426     s->remote->server->n_sessions--;
 427     ovsdb_session_destroy(&s->up);
 428     free(s);
 429 }
 430
 431 static int
 432 ovsdb_jsonrpc_session_run(struct ovsdb_jsonrpc_session *s)
 433 {
 434     jsonrpc_session_run(s->js);
 435     if (s->js_seqno != jsonrpc_session_get_seqno(s->js)) {
 436         s->js_seqno = jsonrpc_session_get_seqno(s->js);
 437         ovsdb_jsonrpc_trigger_complete_all(s);
 438         ovsdb_jsonrpc_monitor_remove_all(s);
 439         ovsdb_jsonrpc_session_unlock_all(s);
 440     }
 441
 442     ovsdb_jsonrpc_trigger_complete_done(s);
 443
 444     if (!jsonrpc_session_get_backlog(s->js)) {
 445         struct jsonrpc_msg *msg;
 446
 447         ovsdb_jsonrpc_monitor_flush_all(s);
 448
 449         msg = jsonrpc_session_recv(s->js);
 450         if (msg) {
 451             if (msg->type == JSONRPC_REQUEST) {
 452                 ovsdb_jsonrpc_session_got_request(s, msg);
 453             } else if (msg->type == JSONRPC_NOTIFY) {
 454                 ovsdb_jsonrpc_session_got_notify(s, msg);
 455             } else {
 456                 VLOG_WARN("%s: received unexpected %s message",
 457                           jsonrpc_session_get_name(s->js),
 458                           jsonrpc_msg_type_to_string(msg->type));
 459                 jsonrpc_session_force_reconnect(s->js);
 460                 jsonrpc_msg_destroy(msg);
 461             }
 462         }
 463     }
 464     return jsonrpc_session_is_alive(s->js) ? 0 : ETIMEDOUT;
 465 }
 466
 467 static void
 468 ovsdb_jsonrpc_session_set_options(struct ovsdb_jsonrpc_session *session,
 469                                   const struct ovsdb_jsonrpc_options *options)
 470 {
 471     jsonrpc_session_set_max_backoff(session->js, options->max_backoff);
 472     jsonrpc_session_set_probe_interval(session->js, options->probe_interval);
 473     jsonrpc_session_set_dscp(session->js, options->dscp);
 474 }
 475
 476 static void
 477 ovsdb_jsonrpc_session_run_all(struct ovsdb_jsonrpc_remote *remote)
 478 {
 479     struct ovsdb_jsonrpc_session *s, *next;
 480
 481     LIST_FOR_EACH_SAFE (s, next, node, &remote->sessions) {
 482         int error = ovsdb_jsonrpc_session_run(s);
 483         if (error) {
 484             ovsdb_jsonrpc_session_close(s);
 485         }
 486     }
 487 }
 488
 489 static void
 490 ovsdb_jsonrpc_session_wait(struct ovsdb_jsonrpc_session *s)
 491 {
 492     jsonrpc_session_wait(s->js);
 493     if (!jsonrpc_session_get_backlog(s->js)) {
 494         if (ovsdb_jsonrpc_monitor_needs_flush(s)) {
 495             poll_immediate_wake();
 496         } else {
 497             jsonrpc_session_recv_wait(s->js);
 498         }
 499     }
 500 }
 501
 502 static void
 503 ovsdb_jsonrpc_session_wait_all(struct ovsdb_jsonrpc_remote *remote)
 504 {
 505     struct ovsdb_jsonrpc_session *s;
 506
 507     LIST_FOR_EACH (s, node, &remote->sessions) {
 508         ovsdb_jsonrpc_session_wait(s);
 509     }
 510 }
 511
 512 static void
 513 ovsdb_jsonrpc_session_get_memory_usage(const struct ovsdb_jsonrpc_session *s,
 514                                        struct simap *usage)
 515 {
 516     simap_increase(usage, "triggers", hmap_count(&s->triggers));
 517     simap_increase(usage, "monitors", hmap_count(&s->monitors));
 518     simap_increase(usage, "backlog", jsonrpc_session_get_backlog(s->js));
 519 }
 520
 521 static void
 522 ovsdb_jsonrpc_session_get_memory_usage_all(
 523     const struct ovsdb_jsonrpc_remote *remote,
 524     struct simap *usage)
 525 {
 526     struct ovsdb_jsonrpc_session *s;
 527
 528     LIST_FOR_EACH (s, node, &remote->sessions) {
 529         ovsdb_jsonrpc_session_get_memory_usage(s, usage);
 530     }
 531 }
 532
 533 static void
 534 ovsdb_jsonrpc_session_close_all(struct ovsdb_jsonrpc_remote *remote)
 535 {
 536     struct ovsdb_jsonrpc_session *s, *next;
 537
 538     LIST_FOR_EACH_SAFE (s, next, node, &remote->sessions) {
 539         ovsdb_jsonrpc_session_close(s);
 540     }
 541 }
 542
 543 /* Forces all of the JSON-RPC sessions managed by 'remote' to disconnect and
 544  * reconnect. */
 545 static void
 546 ovsdb_jsonrpc_session_reconnect_all(struct ovsdb_jsonrpc_remote *remote)
 547 {
 548     struct ovsdb_jsonrpc_session *s, *next;
 549
 550     LIST_FOR_EACH_SAFE (s, next, node, &remote->sessions) {
 551         jsonrpc_session_force_reconnect(s->js);
 552         if (!jsonrpc_session_is_alive(s->js)) {
 553             ovsdb_jsonrpc_session_close(s);
 554         }
 555     }
 556 }
 557
 558 /* Sets the options for all of the JSON-RPC sessions managed by 'remote' to
 559  * 'options'. */
 560 static void
 561 ovsdb_jsonrpc_session_set_all_options(
 562     struct ovsdb_jsonrpc_remote *remote,
 563     const struct ovsdb_jsonrpc_options *options)
 564 {
 565     struct ovsdb_jsonrpc_session *s;
 566
 567     if (remote->listener) {
 568         int error;
 569
 570         error = pstream_set_dscp(remote->listener, options->dscp);
 571         if (error) {
 572             VLOG_ERR("%s: set_dscp failed %s",
 573                      pstream_get_name(remote->listener), ovs_strerror(error));
 574         } else {
 575             remote->dscp = options->dscp;
 576         }
 577         /*
 578          * XXX race window between setting dscp to listening socket
 579          * and accepting socket. Accepted socket may have old dscp value.
 580          * Ignore this race window for now.
 581          */
 582     }
 583     LIST_FOR_EACH (s, node, &remote->sessions) {
 584         ovsdb_jsonrpc_session_set_options(s, options);
 585     }
 586 }
 587
 588 static bool
 589 ovsdb_jsonrpc_session_get_status(const struct ovsdb_jsonrpc_remote *remote,
 590                                  struct ovsdb_jsonrpc_remote_status *status)
 591 {
 592     const struct ovsdb_jsonrpc_session *s;
 593     const struct jsonrpc_session *js;
 594     struct ovsdb_lock_waiter *waiter;
 595     struct reconnect_stats rstats;
 596     struct ds locks_held, locks_waiting, locks_lost;
 597
 598     status->bound_port = (remote->listener
 599                           ? pstream_get_bound_port(remote->listener)
 600                           : htons(0));
 601
 602     if (list_is_empty(&remote->sessions)) {
 603         return false;
 604     }
 605     s = CONTAINER_OF(remote->sessions.next, struct ovsdb_jsonrpc_session, node);
 606     js = s->js;
 607
 608     status->is_connected = jsonrpc_session_is_connected(js);
 609     status->last_error = jsonrpc_session_get_status(js);
 610
 611     jsonrpc_session_get_reconnect_stats(js, &rstats);
 612     status->state = rstats.state;
 613     status->sec_since_connect = rstats.msec_since_connect == UINT_MAX
 614         ? UINT_MAX : rstats.msec_since_connect / 1000;
 615     status->sec_since_disconnect = rstats.msec_since_disconnect == UINT_MAX
 616         ? UINT_MAX : rstats.msec_since_disconnect / 1000;
 617
 618     ds_init(&locks_held);
 619     ds_init(&locks_waiting);
 620     ds_init(&locks_lost);
 621     HMAP_FOR_EACH (waiter, session_node, &s->up.waiters) {
 622         struct ds *string;
 623
 624         string = (ovsdb_lock_waiter_is_owner(waiter) ? &locks_held
 625                   : waiter->mode == OVSDB_LOCK_WAIT ? &locks_waiting
 626                   : &locks_lost);
 627         if (string->length) {
 628             ds_put_char(string, ' ');
 629         }
 630         ds_put_cstr(string, waiter->lock_name);
 631     }
 632     status->locks_held = ds_steal_cstr(&locks_held);
 633     status->locks_waiting = ds_steal_cstr(&locks_waiting);
 634     status->locks_lost = ds_steal_cstr(&locks_lost);
 635
 636     status->n_connections = list_size(&remote->sessions);
 637
 638     return true;
 639 }
 640
 641 /* Examines 'request' to determine the database to which it relates, and then
 642  * searches 's' to find that database:
 643  *
 644  *    - If successful, returns the database and sets '*replyp' to NULL.
 645  *
 646  *    - If no such database exists, returns NULL and sets '*replyp' to an
 647  *      appropriate JSON-RPC error reply, owned by the caller. */
 648 static struct ovsdb *
 649 ovsdb_jsonrpc_lookup_db(const struct ovsdb_jsonrpc_session *s,
 650                         const struct jsonrpc_msg *request,
 651                         struct jsonrpc_msg **replyp)
 652 {
 653     struct json_array *params;
 654     struct ovsdb_error *error;
 655     const char *db_name;
 656     struct ovsdb *db;
 657
 658     params = json_array(request->params);
 659     if (!params->n || params->elems[0]->type != JSON_STRING) {
 660         error = ovsdb_syntax_error(
 661             request->params, NULL,
 662             "%s request params must begin with <db-name>", request->method);
 663         goto error;
 664     }
 665
 666     db_name = params->elems[0]->u.string;
 667     db = shash_find_data(&s->up.server->dbs, db_name);
 668     if (!db) {
 669         error = ovsdb_syntax_error(
 670             request->params, "unknown database",
 671             "%s request specifies unknown database %s",
 672             request->method, db_name);
 673         goto error;
 674     }
 675
 676     *replyp = NULL;
 677     return db;
 678
 679 error:
 680     *replyp = jsonrpc_create_reply(ovsdb_error_to_json(error), request->id);
 681     ovsdb_error_destroy(error);
 682     return NULL;
 683 }
 684
 685 static struct ovsdb_error *
 686 ovsdb_jsonrpc_session_parse_lock_name(const struct jsonrpc_msg *request,
 687                                       const char **lock_namep)
 688 {
 689     const struct json_array *params;
 690
 691     params = json_array(request->params);
 692     if (params->n != 1 || params->elems[0]->type != JSON_STRING ||
 693         !ovsdb_parser_is_id(json_string(params->elems[0]))) {
 694         *lock_namep = NULL;
 695         return ovsdb_syntax_error(request->params, NULL,
 696                                   "%s request params must be <id>",
 697                                   request->method);
 698     }
 699
 700     *lock_namep = json_string(params->elems[0]);
 701     return NULL;
 702 }
 703
 704 static void
 705 ovsdb_jsonrpc_session_notify(struct ovsdb_session *session,
 706                              const char *lock_name,
 707                              const char *method)
 708 {
 709     struct ovsdb_jsonrpc_session *s;
 710     struct json *params;
 711
 712     s = CONTAINER_OF(session, struct ovsdb_jsonrpc_session, up);
 713     params = json_array_create_1(json_string_create(lock_name));
 714     ovsdb_jsonrpc_session_send(s, jsonrpc_create_notify(method, params));
 715 }
 716
 717 static struct jsonrpc_msg *
 718 ovsdb_jsonrpc_session_lock(struct ovsdb_jsonrpc_session *s,
 719                            struct jsonrpc_msg *request,
 720                            enum ovsdb_lock_mode mode)
 721 {
 722     struct ovsdb_lock_waiter *waiter;
 723     struct jsonrpc_msg *reply;
 724     struct ovsdb_error *error;
 725     struct ovsdb_session *victim;
 726     const char *lock_name;
 727     struct json *result;
 728
 729     error = ovsdb_jsonrpc_session_parse_lock_name(request, &lock_name);
 730     if (error) {
 731         goto error;
 732     }
 733
 734     /* Report error if this session has issued a "lock" or "steal" without a
 735      * matching "unlock" for this lock. */
 736     waiter = ovsdb_session_get_lock_waiter(&s->up, lock_name);
 737     if (waiter) {
 738         error = ovsdb_syntax_error(
 739             request->params, NULL,
 740             "must issue \"unlock\" before new \"%s\"", request->method);
 741         goto error;
 742     }
 743
 744     /* Get the lock, add us as a waiter. */
 745     waiter = ovsdb_server_lock(&s->remote->server->up, &s->up, lock_name, mode,
 746                                &victim);
 747     if (victim) {
 748         ovsdb_jsonrpc_session_notify(victim, lock_name, "stolen");
 749     }
 750
 751     result = json_object_create();
 752     json_object_put(result, "locked",
 753                     json_boolean_create(ovsdb_lock_waiter_is_owner(waiter)));
 754
 755     return jsonrpc_create_reply(result, request->id);
 756
 757 error:
 758     reply = jsonrpc_create_reply(ovsdb_error_to_json(error), request->id);
 759     ovsdb_error_destroy(error);
 760     return reply;
 761 }
 762
 763 static void
 764 ovsdb_jsonrpc_session_unlock_all(struct ovsdb_jsonrpc_session *s)
 765 {
 766     struct ovsdb_lock_waiter *waiter, *next;
 767
 768     HMAP_FOR_EACH_SAFE (waiter, next, session_node, &s->up.waiters) {
 769         ovsdb_jsonrpc_session_unlock__(waiter);
 770     }
 771 }
 772
 773 static void
 774 ovsdb_jsonrpc_session_unlock__(struct ovsdb_lock_waiter *waiter)
 775 {
 776     struct ovsdb_lock *lock = waiter->lock;
 777
 778     if (lock) {
 779         struct ovsdb_session *new_owner = ovsdb_lock_waiter_remove(waiter);
 780         if (new_owner) {
 781             ovsdb_jsonrpc_session_notify(new_owner, lock->name, "locked");
 782         } else {
 783             /* ovsdb_server_lock() might have freed 'lock'. */
 784         }
 785     }
 786
 787     ovsdb_lock_waiter_destroy(waiter);
 788 }
 789
 790 static struct jsonrpc_msg *
 791 ovsdb_jsonrpc_session_unlock(struct ovsdb_jsonrpc_session *s,
 792                              struct jsonrpc_msg *request)
 793 {
 794     struct ovsdb_lock_waiter *waiter;
 795     struct jsonrpc_msg *reply;
 796     struct ovsdb_error *error;
 797     const char *lock_name;
 798
 799     error = ovsdb_jsonrpc_session_parse_lock_name(request, &lock_name);
 800     if (error) {
 801         goto error;
 802     }
 803
 804     /* Report error if this session has not issued a "lock" or "steal" for this
 805      * lock. */
 806     waiter = ovsdb_session_get_lock_waiter(&s->up, lock_name);
 807     if (!waiter) {
 808         error = ovsdb_syntax_error(
 809             request->params, NULL, "\"unlock\" without \"lock\" or \"steal\"");
 810         goto error;
 811     }
 812
 813     ovsdb_jsonrpc_session_unlock__(waiter);
 814
 815     return jsonrpc_create_reply(json_object_create(), request->id);
 816
 817 error:
 818     reply = jsonrpc_create_reply(ovsdb_error_to_json(error), request->id);
 819     ovsdb_error_destroy(error);
 820     return reply;
 821 }
 822
 823 static struct jsonrpc_msg *
 824 execute_transaction(struct ovsdb_jsonrpc_session *s, struct ovsdb *db,
 825                     struct jsonrpc_msg *request)
 826 {
 827     ovsdb_jsonrpc_trigger_create(s, db, request->id, request->params);
 828     request->id = NULL;
 829     request->params = NULL;
 830     jsonrpc_msg_destroy(request);
 831     return NULL;
 832 }
 833
 834 static void
 835 ovsdb_jsonrpc_session_got_request(struct ovsdb_jsonrpc_session *s,
 836                                   struct jsonrpc_msg *request)
 837 {
 838     struct jsonrpc_msg *reply;
 839
 840     if (!strcmp(request->method, "transact")) {
 841         struct ovsdb *db = ovsdb_jsonrpc_lookup_db(s, request, &reply);
 842         if (!reply) {
 843             reply = execute_transaction(s, db, request);
 844         }
 845     } else if (!strcmp(request->method, "monitor")) {
 846         struct ovsdb *db = ovsdb_jsonrpc_lookup_db(s, request, &reply);
 847         if (!reply) {
 848             reply = jsonrpc_create_reply(
 849                 ovsdb_jsonrpc_monitor_create(s, db, request->params),
 850                 request->id);
 851         }
 852     } else if (!strcmp(request->method, "monitor_cancel")) {
 853         reply = ovsdb_jsonrpc_monitor_cancel(s, json_array(request->params),
 854                                              request->id);
 855     } else if (!strcmp(request->method, "get_schema")) {
 856         struct ovsdb *db = ovsdb_jsonrpc_lookup_db(s, request, &reply);
 857         if (!reply) {
 858             reply = jsonrpc_create_reply(ovsdb_schema_to_json(db->schema),
 859                                          request->id);
 860         }
 861     } else if (!strcmp(request->method, "list_dbs")) {
 862         size_t n_dbs = shash_count(&s->up.server->dbs);
 863         struct shash_node *node;
 864         struct json **dbs;
 865         size_t i;
 866
 867         dbs = xmalloc(n_dbs * sizeof *dbs);
 868         i = 0;
 869         SHASH_FOR_EACH (node, &s->up.server->dbs) {
 870             dbs[i++] = json_string_create(node->name);
 871         }
 872         reply = jsonrpc_create_reply(json_array_create(dbs, n_dbs),
 873                                      request->id);
 874     } else if (!strcmp(request->method, "lock")) {
 875         reply = ovsdb_jsonrpc_session_lock(s, request, OVSDB_LOCK_WAIT);
 876     } else if (!strcmp(request->method, "steal")) {
 877         reply = ovsdb_jsonrpc_session_lock(s, request, OVSDB_LOCK_STEAL);
 878     } else if (!strcmp(request->method, "unlock")) {
 879         reply = ovsdb_jsonrpc_session_unlock(s, request);
 880     } else if (!strcmp(request->method, "echo")) {
 881         reply = jsonrpc_create_reply(json_clone(request->params), request->id);
 882     } else {
 883         reply = jsonrpc_create_error(json_string_create("unknown method"),
 884                                      request->id);
 885     }
 886
 887     if (reply) {
 888         jsonrpc_msg_destroy(request);
 889         ovsdb_jsonrpc_session_send(s, reply);
 890     }
 891 }
 892
 893 static void
 894 execute_cancel(struct ovsdb_jsonrpc_session *s, struct jsonrpc_msg *request)
 895 {
 896     if (json_array(request->params)->n == 1) {
 897         struct ovsdb_jsonrpc_trigger *t;
 898         struct json *id;
 899
 900         id = request->params->u.array.elems[0];
 901         t = ovsdb_jsonrpc_trigger_find(s, id, json_hash(id, 0));
 902         if (t) {
 903             ovsdb_jsonrpc_trigger_complete(t);
 904         }
 905     }
 906 }
 907
 908 static void
 909 ovsdb_jsonrpc_session_got_notify(struct ovsdb_jsonrpc_session *s,
 910                                  struct jsonrpc_msg *request)
 911 {
 912     if (!strcmp(request->method, "cancel")) {
 913         execute_cancel(s, request);
 914     }
 915     jsonrpc_msg_destroy(request);
 916 }
 917
 918 static void
 919 ovsdb_jsonrpc_session_send(struct ovsdb_jsonrpc_session *s,
 920                            struct jsonrpc_msg *msg)
 921 {
 922     ovsdb_jsonrpc_monitor_flush_all(s);
 923     jsonrpc_session_send(s->js, msg);
 924 }
 925 \f
 926 /* JSON-RPC database server triggers.
 927  *
 928  * (Every transaction is treated as a trigger even if it doesn't actually have
 929  * any "wait" operations.) */
 930
 931 struct ovsdb_jsonrpc_trigger {
 932     struct ovsdb_trigger trigger;
 933     struct hmap_node hmap_node; /* In session's "triggers" hmap. */
 934     struct json *id;
 935 };
 936
 937 static void
 938 ovsdb_jsonrpc_trigger_create(struct ovsdb_jsonrpc_session *s, struct ovsdb *db,
 939                              struct json *id, struct json *params)
 940 {
 941     struct ovsdb_jsonrpc_trigger *t;
 942     size_t hash;
 943
 944     /* Check for duplicate ID. */
 945     hash = json_hash(id, 0);
 946     t = ovsdb_jsonrpc_trigger_find(s, id, hash);
 947     if (t) {
 948         struct jsonrpc_msg *msg;
 949
 950         msg = jsonrpc_create_error(json_string_create("duplicate request ID"),
 951                                    id);
 952         ovsdb_jsonrpc_session_send(s, msg);
 953         json_destroy(id);
 954         json_destroy(params);
 955         return;
 956     }
 957
 958     /* Insert into trigger table. */
 959     t = xmalloc(sizeof *t);
 960     ovsdb_trigger_init(&s->up, db, &t->trigger, params, time_msec());
 961     t->id = id;
 962     hmap_insert(&s->triggers, &t->hmap_node, hash);
 963
 964     /* Complete early if possible. */
 965     if (ovsdb_trigger_is_complete(&t->trigger)) {
 966         ovsdb_jsonrpc_trigger_complete(t);
 967     }
 968 }
 969
 970 static struct ovsdb_jsonrpc_trigger *
 971 ovsdb_jsonrpc_trigger_find(struct ovsdb_jsonrpc_session *s,
 972                            const struct json *id, size_t hash)
 973 {
 974     struct ovsdb_jsonrpc_trigger *t;
 975
 976     HMAP_FOR_EACH_WITH_HASH (t, hmap_node, hash, &s->triggers) {
 977         if (json_equal(t->id, id)) {
 978             return t;
 979         }
 980     }
 981
 982     return NULL;
 983 }
 984
 985 static void
 986 ovsdb_jsonrpc_trigger_complete(struct ovsdb_jsonrpc_trigger *t)
 987 {
 988     struct ovsdb_jsonrpc_session *s;
 989
 990     s = CONTAINER_OF(t->trigger.session, struct ovsdb_jsonrpc_session, up);
 991
 992     if (jsonrpc_session_is_connected(s->js)) {
 993         struct jsonrpc_msg *reply;
 994         struct json *result;
 995
 996         result = ovsdb_trigger_steal_result(&t->trigger);
 997         if (result) {
 998             reply = jsonrpc_create_reply(result, t->id);
 999         } else {
1000             reply = jsonrpc_create_error(json_string_create("canceled"),
1001                                          t->id);
1002         }
1003         ovsdb_jsonrpc_session_send(s, reply);
1004     }
1005
1006     json_destroy(t->id);
1007     ovsdb_trigger_destroy(&t->trigger);
1008     hmap_remove(&s->triggers, &t->hmap_node);
1009     free(t);
1010 }
1011
1012 static void
1013 ovsdb_jsonrpc_trigger_complete_all(struct ovsdb_jsonrpc_session *s)
1014 {
1015     struct ovsdb_jsonrpc_trigger *t, *next;
1016     HMAP_FOR_EACH_SAFE (t, next, hmap_node, &s->triggers) {
1017         ovsdb_jsonrpc_trigger_complete(t);
1018     }
1019 }
1020
1021 static void
1022 ovsdb_jsonrpc_trigger_complete_done(struct ovsdb_jsonrpc_session *s)
1023 {
1024     while (!list_is_empty(&s->up.completions)) {
1025         struct ovsdb_jsonrpc_trigger *t
1026             = CONTAINER_OF(s->up.completions.next,
1027                            struct ovsdb_jsonrpc_trigger, trigger.node);
1028         ovsdb_jsonrpc_trigger_complete(t);
1029     }
1030 }
1031 \f
1032 /* JSON-RPC database table monitors. */
1033
1034 enum ovsdb_jsonrpc_monitor_selection {
1035     OJMS_INITIAL = 1 << 0,      /* All rows when monitor is created. */
1036     OJMS_INSERT = 1 << 1,       /* New rows. */
1037     OJMS_DELETE = 1 << 2,       /* Deleted rows. */
1038     OJMS_MODIFY = 1 << 3        /* Modified rows. */
1039 };
1040
1041 /* A particular column being monitored. */
1042 struct ovsdb_jsonrpc_monitor_column {
1043     const struct ovsdb_column *column;
1044     enum ovsdb_jsonrpc_monitor_selection select;
1045 };
1046
1047 /* A row that has changed in a monitored table. */
1048 struct ovsdb_jsonrpc_monitor_row {
1049     struct hmap_node hmap_node; /* In ovsdb_jsonrpc_monitor_table.changes. */
1050     struct uuid uuid;           /* UUID of row that changed. */
1051     struct ovsdb_datum *old;    /* Old data, NULL for an inserted row. */
1052     struct ovsdb_datum *new;    /* New data, NULL for a deleted row. */
1053 };
1054
1055 /* A particular table being monitored. */
1056 struct ovsdb_jsonrpc_monitor_table {
1057     const struct ovsdb_table *table;
1058
1059     /* This is the union (bitwise-OR) of the 'select' values in all of the
1060      * members of 'columns' below. */
1061     enum ovsdb_jsonrpc_monitor_selection select;
1062
1063     /* Columns being monitored. */
1064     struct ovsdb_jsonrpc_monitor_column *columns;
1065     size_t n_columns;
1066
1067     /* Contains 'struct ovsdb_jsonrpc_monitor_row's for rows that have been
1068      * updated but not yet flushed to the jsonrpc connection. */
1069     struct hmap changes;
1070 };
1071
1072 /* A collection of tables being monitored. */
1073 struct ovsdb_jsonrpc_monitor {
1074     struct ovsdb_replica replica;
1075     struct ovsdb_jsonrpc_session *session;
1076     struct ovsdb *db;
1077     struct hmap_node node;      /* In ovsdb_jsonrpc_session's "monitors". */
1078
1079     struct json *monitor_id;
1080     struct shash tables;     /* Holds "struct ovsdb_jsonrpc_monitor_table"s. */
1081 };
1082
1083 static const struct ovsdb_replica_class ovsdb_jsonrpc_replica_class;
1084
1085 struct ovsdb_jsonrpc_monitor *ovsdb_jsonrpc_monitor_find(
1086     struct ovsdb_jsonrpc_session *, const struct json *monitor_id);
1087 static void ovsdb_jsonrpc_monitor_destroy(struct ovsdb_replica *);
1088 static struct json *ovsdb_jsonrpc_monitor_get_initial(
1089     const struct ovsdb_jsonrpc_monitor *);
1090
1091 static bool
1092 parse_bool(struct ovsdb_parser *parser, const char *name, bool default_value)
1093 {
1094     const struct json *json;
1095
1096     json = ovsdb_parser_member(parser, name, OP_BOOLEAN | OP_OPTIONAL);
1097     return json ? json_boolean(json) : default_value;
1098 }
1099
1100 struct ovsdb_jsonrpc_monitor *
1101 ovsdb_jsonrpc_monitor_find(struct ovsdb_jsonrpc_session *s,
1102                            const struct json *monitor_id)
1103 {
1104     struct ovsdb_jsonrpc_monitor *m;
1105
1106     HMAP_FOR_EACH_WITH_HASH (m, node, json_hash(monitor_id, 0), &s->monitors) {
1107         if (json_equal(m->monitor_id, monitor_id)) {
1108             return m;
1109         }
1110     }
1111
1112     return NULL;
1113 }
1114
1115 static void
1116 ovsdb_jsonrpc_add_monitor_column(struct ovsdb_jsonrpc_monitor_table *mt,
1117                                  const struct ovsdb_column *column,
1118                                  enum ovsdb_jsonrpc_monitor_selection select,
1119                                  size_t *allocated_columns)
1120 {
1121     struct ovsdb_jsonrpc_monitor_column *c;
1122
1123     if (mt->n_columns >= *allocated_columns) {
1124         mt->columns = x2nrealloc(mt->columns, allocated_columns,
1125                                  sizeof *mt->columns);
1126     }
1127
1128     c = &mt->columns[mt->n_columns++];
1129     c->column = column;
1130     c->select = select;
1131 }
1132
1133 static int
1134 compare_ovsdb_jsonrpc_monitor_column(const void *a_, const void *b_)
1135 {
1136     const struct ovsdb_jsonrpc_monitor_column *a = a_;
1137     const struct ovsdb_jsonrpc_monitor_column *b = b_;
1138
1139     return a->column < b->column ? -1 : a->column > b->column;
1140 }
1141
1142 static struct ovsdb_error * WARN_UNUSED_RESULT
1143 ovsdb_jsonrpc_parse_monitor_request(struct ovsdb_jsonrpc_monitor_table *mt,
1144                                     const struct json *monitor_request,
1145                                     size_t *allocated_columns)
1146 {
1147     const struct ovsdb_table_schema *ts = mt->table->schema;
1148     enum ovsdb_jsonrpc_monitor_selection select;
1149     const struct json *columns, *select_json;
1150     struct ovsdb_parser parser;
1151     struct ovsdb_error *error;
1152
1153     ovsdb_parser_init(&parser, monitor_request, "table %s", ts->name);
1154     columns = ovsdb_parser_member(&parser, "columns", OP_ARRAY | OP_OPTIONAL);
1155     select_json = ovsdb_parser_member(&parser, "select",
1156                                       OP_OBJECT | OP_OPTIONAL);
1157     error = ovsdb_parser_finish(&parser);
1158     if (error) {
1159         return error;
1160     }
1161
1162     if (select_json) {
1163         select = 0;
1164         ovsdb_parser_init(&parser, select_json, "table %s select", ts->name);
1165         if (parse_bool(&parser, "initial", true)) {
1166             select |= OJMS_INITIAL;
1167         }
1168         if (parse_bool(&parser, "insert", true)) {
1169             select |= OJMS_INSERT;
1170         }
1171         if (parse_bool(&parser, "delete", true)) {
1172             select |= OJMS_DELETE;
1173         }
1174         if (parse_bool(&parser, "modify", true)) {
1175             select |= OJMS_MODIFY;
1176         }
1177         error = ovsdb_parser_finish(&parser);
1178         if (error) {
1179             return error;
1180         }
1181     } else {
1182         select = OJMS_INITIAL | OJMS_INSERT | OJMS_DELETE | OJMS_MODIFY;
1183     }
1184     mt->select |= select;
1185
1186     if (columns) {
1187         size_t i;
1188
1189         if (columns->type != JSON_ARRAY) {
1190             return ovsdb_syntax_error(columns, NULL,
1191                                       "array of column names expected");
1192         }
1193
1194         for (i = 0; i < columns->u.array.n; i++) {
1195             const struct ovsdb_column *column;
1196             const char *s;
1197
1198             if (columns->u.array.elems[i]->type != JSON_STRING) {
1199                 return ovsdb_syntax_error(columns, NULL,
1200                                           "array of column names expected");
1201             }
1202
1203             s = columns->u.array.elems[i]->u.string;
1204             column = shash_find_data(&mt->table->schema->columns, s);
1205             if (!column) {
1206                 return ovsdb_syntax_error(columns, NULL, "%s is not a valid "
1207                                           "column name", s);
1208             }
1209             ovsdb_jsonrpc_add_monitor_column(mt, column, select,
1210                                              allocated_columns);
1211         }
1212     } else {
1213         struct shash_node *node;
1214
1215         SHASH_FOR_EACH (node, &ts->columns) {
1216             const struct ovsdb_column *column = node->data;
1217             if (column->index != OVSDB_COL_UUID) {
1218                 ovsdb_jsonrpc_add_monitor_column(mt, column, select,
1219                                                  allocated_columns);
1220             }
1221         }
1222     }
1223
1224     return NULL;
1225 }
1226
1227 static struct json *
1228 ovsdb_jsonrpc_monitor_create(struct ovsdb_jsonrpc_session *s, struct ovsdb *db,
1229                              struct json *params)
1230 {
1231     struct ovsdb_jsonrpc_monitor *m = NULL;
1232     struct json *monitor_id, *monitor_requests;
1233     struct ovsdb_error *error = NULL;
1234     struct shash_node *node;
1235     struct json *json;
1236
1237     if (json_array(params)->n != 3) {
1238         error = ovsdb_syntax_error(params, NULL, "invalid parameters");
1239         goto error;
1240     }
1241     monitor_id = params->u.array.elems[1];
1242     monitor_requests = params->u.array.elems[2];
1243     if (monitor_requests->type != JSON_OBJECT) {
1244         error = ovsdb_syntax_error(monitor_requests, NULL,
1245                                    "monitor-requests must be object");
1246         goto error;
1247     }
1248
1249     if (ovsdb_jsonrpc_monitor_find(s, monitor_id)) {
1250         error = ovsdb_syntax_error(monitor_id, NULL, "duplicate monitor ID");
1251         goto error;
1252     }
1253
1254     m = xzalloc(sizeof *m);
1255     ovsdb_replica_init(&m->replica, &ovsdb_jsonrpc_replica_class);
1256     ovsdb_add_replica(db, &m->replica);
1257     m->session = s;
1258     m->db = db;
1259     hmap_insert(&s->monitors, &m->node, json_hash(monitor_id, 0));
1260     m->monitor_id = json_clone(monitor_id);
1261     shash_init(&m->tables);
1262
1263     SHASH_FOR_EACH (node, json_object(monitor_requests)) {
1264         const struct ovsdb_table *table;
1265         struct ovsdb_jsonrpc_monitor_table *mt;
1266         size_t allocated_columns;
1267         const struct json *mr_value;
1268         size_t i;
1269
1270         table = ovsdb_get_table(m->db, node->name);
1271         if (!table) {
1272             error = ovsdb_syntax_error(NULL, NULL,
1273                                        "no table named %s", node->name);
1274             goto error;
1275         }
1276
1277         mt = xzalloc(sizeof *mt);
1278         mt->table = table;
1279         hmap_init(&mt->changes);
1280         shash_add(&m->tables, table->schema->name, mt);
1281
1282         /* Parse columns. */
1283         mr_value = node->data;
1284         allocated_columns = 0;
1285         if (mr_value->type == JSON_ARRAY) {
1286             const struct json_array *array = &mr_value->u.array;
1287
1288             for (i = 0; i < array->n; i++) {
1289                 error = ovsdb_jsonrpc_parse_monitor_request(
1290                     mt, array->elems[i], &allocated_columns);
1291                 if (error) {
1292                     goto error;
1293                 }
1294             }
1295         } else {
1296             error = ovsdb_jsonrpc_parse_monitor_request(
1297                 mt, mr_value, &allocated_columns);
1298             if (error) {
1299                 goto error;
1300             }
1301         }
1302
1303         /* Check for duplicate columns. */
1304         qsort(mt->columns, mt->n_columns, sizeof *mt->columns,
1305               compare_ovsdb_jsonrpc_monitor_column);
1306         for (i = 1; i < mt->n_columns; i++) {
1307             if (mt->columns[i].column == mt->columns[i - 1].column) {
1308                 error = ovsdb_syntax_error(mr_value, NULL, "column %s "
1309                                            "mentioned more than once",
1310                                            mt->columns[i].column->name);
1311                 goto error;
1312             }
1313         }
1314     }
1315
1316     return ovsdb_jsonrpc_monitor_get_initial(m);
1317
1318 error:
1319     if (m) {
1320         ovsdb_remove_replica(m->db, &m->replica);
1321     }
1322
1323     json = ovsdb_error_to_json(error);
1324     ovsdb_error_destroy(error);
1325     return json;
1326 }
1327
1328 static struct jsonrpc_msg *
1329 ovsdb_jsonrpc_monitor_cancel(struct ovsdb_jsonrpc_session *s,
1330                              struct json_array *params,
1331                              const struct json *request_id)
1332 {
1333     if (params->n != 1) {
1334         return jsonrpc_create_error(json_string_create("invalid parameters"),
1335                                     request_id);
1336     } else {
1337         struct ovsdb_jsonrpc_monitor *m;
1338
1339         m = ovsdb_jsonrpc_monitor_find(s, params->elems[0]);
1340         if (!m) {
1341             return jsonrpc_create_error(json_string_create("unknown monitor"),
1342                                         request_id);
1343         } else {
1344             ovsdb_remove_replica(m->db, &m->replica);
1345             return jsonrpc_create_reply(json_object_create(), request_id);
1346         }
1347     }
1348 }
1349
1350 static void
1351 ovsdb_jsonrpc_monitor_remove_all(struct ovsdb_jsonrpc_session *s)
1352 {
1353     struct ovsdb_jsonrpc_monitor *m, *next;
1354
1355     HMAP_FOR_EACH_SAFE (m, next, node, &s->monitors) {
1356         ovsdb_remove_replica(m->db, &m->replica);
1357     }
1358 }
1359
1360 static struct ovsdb_jsonrpc_monitor *
1361 ovsdb_jsonrpc_monitor_cast(struct ovsdb_replica *replica)
1362 {
1363     ovs_assert(replica->class == &ovsdb_jsonrpc_replica_class);
1364     return CONTAINER_OF(replica, struct ovsdb_jsonrpc_monitor, replica);
1365 }
1366
1367 struct ovsdb_jsonrpc_monitor_aux {
1368     const struct ovsdb_jsonrpc_monitor *monitor;
1369     struct ovsdb_jsonrpc_monitor_table *mt;
1370 };
1371
1372 /* Finds and returns the ovsdb_jsonrpc_monitor_row in 'mt->changes' for the
1373  * given 'uuid', or NULL if there is no such row. */
1374 static struct ovsdb_jsonrpc_monitor_row *
1375 ovsdb_jsonrpc_monitor_row_find(const struct ovsdb_jsonrpc_monitor_table *mt,
1376                                const struct uuid *uuid)
1377 {
1378     struct ovsdb_jsonrpc_monitor_row *row;
1379
1380     HMAP_FOR_EACH_WITH_HASH (row, hmap_node, uuid_hash(uuid), &mt->changes) {
1381         if (uuid_equals(uuid, &row->uuid)) {
1382             return row;
1383         }
1384     }
1385     return NULL;
1386 }
1387
1388 /* Allocates an array of 'mt->n_columns' ovsdb_datums and initializes them as
1389  * copies of the data in 'row' drawn from the columns represented by
1390  * mt->columns[].  Returns the array.
1391  *
1392  * If 'row' is NULL, returns NULL. */
1393 static struct ovsdb_datum *
1394 clone_monitor_row_data(const struct ovsdb_jsonrpc_monitor_table *mt,
1395                        const struct ovsdb_row *row)
1396 {
1397     struct ovsdb_datum *data;
1398     size_t i;
1399
1400     if (!row) {
1401         return NULL;
1402     }
1403
1404     data = xmalloc(mt->n_columns * sizeof *data);
1405     for (i = 0; i < mt->n_columns; i++) {
1406         const struct ovsdb_column *c = mt->columns[i].column;
1407         const struct ovsdb_datum *src = &row->fields[c->index];
1408         struct ovsdb_datum *dst = &data[i];
1409         const struct ovsdb_type *type = &c->type;
1410
1411         ovsdb_datum_clone(dst, src, type);
1412     }
1413     return data;
1414 }
1415
1416 /* Replaces the mt->n_columns ovsdb_datums in row[] by copies of the data from
1417  * in 'row' drawn from the columns represented by mt->columns[]. */
1418 static void
1419 update_monitor_row_data(const struct ovsdb_jsonrpc_monitor_table *mt,
1420                         const struct ovsdb_row *row,
1421                         struct ovsdb_datum *data)
1422 {
1423     size_t i;
1424
1425     for (i = 0; i < mt->n_columns; i++) {
1426         const struct ovsdb_column *c = mt->columns[i].column;
1427         const struct ovsdb_datum *src = &row->fields[c->index];
1428         struct ovsdb_datum *dst = &data[i];
1429         const struct ovsdb_type *type = &c->type;
1430
1431         if (!ovsdb_datum_equals(src, dst, type)) {
1432             ovsdb_datum_destroy(dst, type);
1433             ovsdb_datum_clone(dst, src, type);
1434         }
1435     }
1436 }
1437
1438 /* Frees all of the mt->n_columns ovsdb_datums in data[], using the types taken
1439  * from mt->columns[], plus 'data' itself. */
1440 static void
1441 free_monitor_row_data(const struct ovsdb_jsonrpc_monitor_table *mt,
1442                       struct ovsdb_datum *data)
1443 {
1444     if (data) {
1445         size_t i;
1446
1447         for (i = 0; i < mt->n_columns; i++) {
1448             const struct ovsdb_column *c = mt->columns[i].column;
1449
1450             ovsdb_datum_destroy(&data[i], &c->type);
1451         }
1452         free(data);
1453     }
1454 }
1455
1456 /* Frees 'row', which must have been created from 'mt'. */
1457 static void
1458 ovsdb_jsonrpc_monitor_row_destroy(const struct ovsdb_jsonrpc_monitor_table *mt,
1459                                   struct ovsdb_jsonrpc_monitor_row *row)
1460 {
1461     if (row) {
1462         free_monitor_row_data(mt, row->old);
1463         free_monitor_row_data(mt, row->new);
1464         free(row);
1465     }
1466 }
1467
1468 static bool
1469 ovsdb_jsonrpc_monitor_change_cb(const struct ovsdb_row *old,
1470                                 const struct ovsdb_row *new,
1471                                 const unsigned long int *changed OVS_UNUSED,
1472                                 void *aux_)
1473 {
1474     struct ovsdb_jsonrpc_monitor_aux *aux = aux_;
1475     const struct ovsdb_jsonrpc_monitor *m = aux->monitor;
1476     struct ovsdb_table *table = new ? new->table : old->table;
1477     const struct uuid *uuid = ovsdb_row_get_uuid(new ? new : old);
1478     struct ovsdb_jsonrpc_monitor_row *change;
1479     struct ovsdb_jsonrpc_monitor_table *mt;
1480
1481     if (!aux->mt || table != aux->mt->table) {
1482         aux->mt = shash_find_data(&m->tables, table->schema->name);
1483         if (!aux->mt) {
1484             /* We don't care about rows in this table at all.  Tell the caller
1485              * to skip it.  */
1486             return false;
1487         }
1488     }
1489     mt = aux->mt;
1490
1491     change = ovsdb_jsonrpc_monitor_row_find(mt, uuid);
1492     if (!change) {
1493         change = xmalloc(sizeof *change);
1494         hmap_insert(&mt->changes, &change->hmap_node, uuid_hash(uuid));
1495         change->uuid = *uuid;
1496         change->old = clone_monitor_row_data(mt, old);
1497         change->new = clone_monitor_row_data(mt, new);
1498     } else {
1499         if (new) {
1500             update_monitor_row_data(mt, new, change->new);
1501         } else {
1502             free_monitor_row_data(mt, change->new);
1503             change->new = NULL;
1504
1505             if (!change->old) {
1506                 /* This row was added then deleted.  Forget about it. */
1507                 hmap_remove(&mt->changes, &change->hmap_node);
1508                 free(change);
1509             }
1510         }
1511     }
1512     return true;
1513 }
1514
1515 /* Returns JSON for a <row-update> (as described in RFC 7047) for 'row' within
1516  * 'mt', or NULL if no row update should be sent.
1517  *
1518  * The caller should specify 'initial' as true if the returned JSON is going to
1519  * be used as part of the initial reply to a "monitor" request, false if it is
1520  * going to be used as part of an "update" notification.
1521  *
1522  * 'changed' must be a scratch buffer for internal use that is at least
1523  * bitmap_n_bytes(mt->n_columns) bytes long. */
1524 static struct json *
1525 ovsdb_jsonrpc_monitor_compose_row_update(
1526     const struct ovsdb_jsonrpc_monitor_table *mt,
1527     const struct ovsdb_jsonrpc_monitor_row *row,
1528     bool initial, unsigned long int *changed)
1529 {
1530     enum ovsdb_jsonrpc_monitor_selection type;
1531     struct json *old_json, *new_json;
1532     struct json *row_json;
1533     size_t i;
1534
1535     type = (initial ? OJMS_INITIAL
1536             : !row->old ? OJMS_INSERT
1537             : !row->new ? OJMS_DELETE
1538             : OJMS_MODIFY);
1539     if (!(mt->select & type)) {
1540         return NULL;
1541     }
1542
1543     if (type == OJMS_MODIFY) {
1544         size_t n_changes;
1545
1546         n_changes = 0;
1547         memset(changed, 0, bitmap_n_bytes(mt->n_columns));
1548         for (i = 0; i < mt->n_columns; i++) {
1549             const struct ovsdb_column *c = mt->columns[i].column;
1550             if (!ovsdb_datum_equals(&row->old[i], &row->new[i], &c->type)) {
1551                 bitmap_set1(changed, i);
1552                 n_changes++;
1553             }
1554         }
1555         if (!n_changes) {
1556             /* No actual changes: presumably a row changed and then
1557              * changed back later. */
1558             return NULL;
1559         }
1560     }
1561
1562     row_json = json_object_create();
1563     old_json = new_json = NULL;
1564     if (type & (OJMS_DELETE | OJMS_MODIFY)) {
1565         old_json = json_object_create();
1566         json_object_put(row_json, "old", old_json);
1567     }
1568     if (type & (OJMS_INITIAL | OJMS_INSERT | OJMS_MODIFY)) {
1569         new_json = json_object_create();
1570         json_object_put(row_json, "new", new_json);
1571     }
1572     for (i = 0; i < mt->n_columns; i++) {
1573         const struct ovsdb_jsonrpc_monitor_column *c = &mt->columns[i];
1574
1575         if (!(type & c->select)) {
1576             /* We don't care about this type of change for this
1577              * particular column (but we will care about it for some
1578              * other column). */
1579             continue;
1580         }
1581
1582         if ((type == OJMS_MODIFY && bitmap_is_set(changed, i))
1583             || type == OJMS_DELETE) {
1584             json_object_put(old_json, c->column->name,
1585                             ovsdb_datum_to_json(&row->old[i],
1586                                                 &c->column->type));
1587         }
1588         if (type & (OJMS_INITIAL | OJMS_INSERT | OJMS_MODIFY)) {
1589             json_object_put(new_json, c->column->name,
1590                             ovsdb_datum_to_json(&row->new[i],
1591                                                 &c->column->type));
1592         }
1593     }
1594
1595     return row_json;
1596 }
1597
1598 /* Constructs and returns JSON for a <table-updates> object (as described in
1599  * RFC 7047) for all the outstanding changes within 'monitor', and deletes all
1600  * the outstanding changes from 'monitor'.  Returns NULL if no update needs to
1601  * be sent.
1602  *
1603  * The caller should specify 'initial' as true if the returned JSON is going to
1604  * be used as part of the initial reply to a "monitor" request, false if it is
1605  * going to be used as part of an "update" notification. */
1606 static struct json *
1607 ovsdb_jsonrpc_monitor_compose_table_update(
1608     const struct ovsdb_jsonrpc_monitor *monitor, bool initial)
1609 {
1610     struct shash_node *node;
1611     unsigned long int *changed;
1612     struct json *json;
1613     size_t max_columns;
1614
1615     max_columns = 0;
1616     SHASH_FOR_EACH (node, &monitor->tables) {
1617         struct ovsdb_jsonrpc_monitor_table *mt = node->data;
1618
1619         max_columns = MAX(max_columns, mt->n_columns);
1620     }
1621     changed = xmalloc(bitmap_n_bytes(max_columns));
1622
1623     json = NULL;
1624     SHASH_FOR_EACH (node, &monitor->tables) {
1625         struct ovsdb_jsonrpc_monitor_table *mt = node->data;
1626         struct ovsdb_jsonrpc_monitor_row *row, *next;
1627         struct json *table_json = NULL;
1628
1629         HMAP_FOR_EACH_SAFE (row, next, hmap_node, &mt->changes) {
1630             struct json *row_json;
1631
1632             row_json = ovsdb_jsonrpc_monitor_compose_row_update(
1633                 mt, row, initial, changed);
1634             if (row_json) {
1635                 char uuid[UUID_LEN + 1];
1636
1637                 /* Create JSON object for transaction overall. */
1638                 if (!json) {
1639                     json = json_object_create();
1640                 }
1641
1642                 /* Create JSON object for transaction on this table. */
1643                 if (!table_json) {
1644                     table_json = json_object_create();
1645                     json_object_put(json, mt->table->schema->name, table_json);
1646                 }
1647
1648                 /* Add JSON row to JSON table. */
1649                 snprintf(uuid, sizeof uuid, UUID_FMT, UUID_ARGS(&row->uuid));
1650                 json_object_put(table_json, uuid, row_json);
1651             }
1652
1653             hmap_remove(&mt->changes, &row->hmap_node);
1654             ovsdb_jsonrpc_monitor_row_destroy(mt, row);
1655         }
1656     }
1657
1658     free(changed);
1659
1660     return json;
1661 }
1662
1663 static bool
1664 ovsdb_jsonrpc_monitor_needs_flush(struct ovsdb_jsonrpc_session *s)
1665 {
1666     struct ovsdb_jsonrpc_monitor *m;
1667
1668     HMAP_FOR_EACH (m, node, &s->monitors) {
1669         struct shash_node *node;
1670
1671         SHASH_FOR_EACH (node, &m->tables) {
1672             struct ovsdb_jsonrpc_monitor_table *mt = node->data;
1673
1674             if (!hmap_is_empty(&mt->changes)) {
1675                 return true;
1676             }
1677         }
1678     }
1679
1680     return false;
1681 }
1682
1683 static void
1684 ovsdb_jsonrpc_monitor_flush_all(struct ovsdb_jsonrpc_session *s)
1685 {
1686     struct ovsdb_jsonrpc_monitor *m;
1687
1688     HMAP_FOR_EACH (m, node, &s->monitors) {
1689         struct json *json;
1690
1691         json = ovsdb_jsonrpc_monitor_compose_table_update(m, false);
1692         if (json) {
1693             struct jsonrpc_msg *msg;
1694             struct json *params;
1695
1696             params = json_array_create_2(json_clone(m->monitor_id), json);
1697             msg = jsonrpc_create_notify("update", params);
1698             jsonrpc_session_send(s->js, msg);
1699         }
1700     }
1701 }
1702
1703 static void
1704 ovsdb_jsonrpc_monitor_init_aux(struct ovsdb_jsonrpc_monitor_aux *aux,
1705                                const struct ovsdb_jsonrpc_monitor *m)
1706 {
1707     aux->monitor = m;
1708     aux->mt = NULL;
1709 }
1710
1711 static struct ovsdb_error *
1712 ovsdb_jsonrpc_monitor_commit(struct ovsdb_replica *replica,
1713                              const struct ovsdb_txn *txn,
1714                              bool durable OVS_UNUSED)
1715 {
1716     struct ovsdb_jsonrpc_monitor *m = ovsdb_jsonrpc_monitor_cast(replica);
1717     struct ovsdb_jsonrpc_monitor_aux aux;
1718
1719     ovsdb_jsonrpc_monitor_init_aux(&aux, m);
1720     ovsdb_txn_for_each_change(txn, ovsdb_jsonrpc_monitor_change_cb, &aux);
1721
1722     return NULL;
1723 }
1724
1725 static struct json *
1726 ovsdb_jsonrpc_monitor_get_initial(const struct ovsdb_jsonrpc_monitor *m)
1727 {
1728     struct ovsdb_jsonrpc_monitor_aux aux;
1729     struct shash_node *node;
1730     struct json *json;
1731
1732     ovsdb_jsonrpc_monitor_init_aux(&aux, m);
1733     SHASH_FOR_EACH (node, &m->tables) {
1734         struct ovsdb_jsonrpc_monitor_table *mt = node->data;
1735
1736         if (mt->select & OJMS_INITIAL) {
1737             struct ovsdb_row *row;
1738
1739             HMAP_FOR_EACH (row, hmap_node, &mt->table->rows) {
1740                 ovsdb_jsonrpc_monitor_change_cb(NULL, row, NULL, &aux);
1741             }
1742         }
1743     }
1744     json = ovsdb_jsonrpc_monitor_compose_table_update(m, true);
1745     return json ? json : json_object_create();
1746 }
1747
1748 static void
1749 ovsdb_jsonrpc_monitor_destroy(struct ovsdb_replica *replica)
1750 {
1751     struct ovsdb_jsonrpc_monitor *m = ovsdb_jsonrpc_monitor_cast(replica);
1752     struct shash_node *node;
1753
1754     json_destroy(m->monitor_id);
1755     SHASH_FOR_EACH (node, &m->tables) {
1756         struct ovsdb_jsonrpc_monitor_table *mt = node->data;
1757         struct ovsdb_jsonrpc_monitor_row *row, *next;
1758
1759         HMAP_FOR_EACH_SAFE (row, next, hmap_node, &mt->changes) {
1760             hmap_remove(&mt->changes, &row->hmap_node);
1761             ovsdb_jsonrpc_monitor_row_destroy(mt, row);
1762         }
1763         hmap_destroy(&mt->changes);
1764
1765         free(mt->columns);
1766         free(mt);
1767     }
1768     shash_destroy(&m->tables);
1769     hmap_remove(&m->session->monitors, &m->node);
1770     free(m);
1771 }
1772
1773 static const struct ovsdb_replica_class ovsdb_jsonrpc_replica_class = {
1774     ovsdb_jsonrpc_monitor_commit,
1775     ovsdb_jsonrpc_monitor_destroy
1776 };