src/afb-stub-ws.c

   1 /*
   2  * Copyright (C) 2015-2019 "IoT.bzh"
   3  * Author José Bollo <jose.bollo@iot.bzh>
   4  *
   5  * Licensed under the Apache License, Version 2.0 (the "License");
   6  * you may not use this file except in compliance with the License.
   7  * You may obtain a copy of the License at
   8  *
   9  *   http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  * Unless required by applicable law or agreed to in writing, software
  12  * distributed under the License is distributed on an "AS IS" BASIS,
  13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14  * See the License for the specific language governing permissions and
  15  * limitations under the License.
  16  */
  17
  18 #define _GNU_SOURCE
  19
  20 #include <stdlib.h>
  21 #include <string.h>
  22 #include <assert.h>
  23 #include <fcntl.h>
  24 #include <unistd.h>
  25 #include <errno.h>
  26 #include <endian.h>
  27 #include <netdb.h>
  28 #include <sys/types.h>
  29 #include <sys/socket.h>
  30 #include <sys/un.h>
  31 #include <pthread.h>
  32
  33 #include <json-c/json.h>
  34
  35 #include <afb/afb-event-x2.h>
  36
  37 #include "afb-session.h"
  38 #include "afb-cred.h"
  39 #include "afb-api.h"
  40 #include "afb-apiset.h"
  41 #include "afb-proto-ws.h"
  42 #include "afb-stub-ws.h"
  43 #include "afb-context.h"
  44 #include "afb-evt.h"
  45 #include "afb-xreq.h"
  46 #include "verbose.h"
  47 #include "fdev.h"
  48 #include "jobs.h"
  49
  50 struct afb_stub_ws;
  51
  52
  53 /**
  54  * structure for a ws request: requests on server side
  55  */
  56 struct server_req {
  57         struct afb_xreq xreq;           /**< the xreq */
  58         struct afb_stub_ws *stubws;     /**< the client of the request */
  59         struct afb_proto_ws_call *call; /**< the incoming call */
  60 };
  61
  62 /**
  63  * structure for recording events on client side
  64  */
  65 struct client_event
  66 {
  67         struct client_event *next;      /**< link to the next */
  68         struct afb_event_x2 *event;     /**< the local event */
  69         int id;                         /**< the identifier */
  70         int refcount;                   /**< a reference count */
  71 };
  72
  73 /**
  74  * structure for jobs of describing
  75  */
  76 struct server_describe
  77 {
  78         struct afb_stub_ws *stubws;
  79         struct afb_proto_ws_describe *describe;
  80 };
  81
  82 /**
  83  * structure for recording sessions
  84  */
  85 struct server_session
  86 {
  87         struct server_session *next;
  88         struct afb_session *session;
  89 };
  90
  91 /******************* stub description for client or servers ******************/
  92
  93 struct afb_stub_ws
  94 {
  95         /* protocol */
  96         struct afb_proto_ws *proto;
  97
  98         /* apiset */
  99         struct afb_apiset *apiset;
 100
 101         /* on hangup callback */
 102         void (*on_hangup)(struct afb_stub_ws *);
 103
 104         union {
 105                 /* server side */
 106                 struct {
 107                         /* listener for events */
 108                         struct afb_evt_listener *listener;
 109
 110                         /* sessions */
 111                         struct server_session *sessions;
 112
 113                         /* credentials of the client */
 114                         struct afb_cred *cred;
 115                 };
 116
 117                 /* client side */
 118                 struct {
 119                         /* event replica  */
 120                         struct client_event *events;
 121
 122                         /* robustify */
 123                         struct {
 124                                 struct fdev *(*reopen)(void*);
 125                                 void *closure;
 126                                 void (*release)(void*);
 127                         } robust;
 128                 };
 129         };
 130
 131         /* count of references */
 132         unsigned refcount;
 133
 134         /* type of the stub: 0=server, 1=client */
 135         uint8_t is_client;
 136
 137         /* the api name */
 138         char apiname[];
 139 };
 140
 141 static struct afb_proto_ws *afb_stub_ws_create_proto(struct afb_stub_ws *stubws, struct fdev *fdev, uint8_t server);
 142
 143 /******************* ws request part for server *****************/
 144
 145 /* decrement the reference count of the request and free/release it on falling to null */
 146 static void server_req_destroy_cb(struct afb_xreq *xreq)
 147 {
 148         struct server_req *wreq = CONTAINER_OF_XREQ(struct server_req, xreq);
 149
 150         afb_context_disconnect(&wreq->xreq.context);
 151         afb_cred_unref(wreq->xreq.cred);
 152         json_object_put(wreq->xreq.json);
 153         afb_proto_ws_call_unref(wreq->call);
 154         afb_stub_ws_unref(wreq->stubws);
 155         free(wreq);
 156 }
 157
 158 static void server_req_reply_cb(struct afb_xreq *xreq, struct json_object *obj, const char *error, const char *info)
 159 {
 160         int rc;
 161         struct server_req *wreq = CONTAINER_OF_XREQ(struct server_req, xreq);
 162
 163         rc = afb_proto_ws_call_reply(wreq->call, obj, error, info);
 164         if (rc < 0)
 165                 ERROR("error while sending reply");
 166         json_object_put(obj);
 167 }
 168
 169 static int server_req_subscribe_cb(struct afb_xreq *xreq, struct afb_event_x2 *event)
 170 {
 171         int rc;
 172         struct server_req *wreq = CONTAINER_OF_XREQ(struct server_req, xreq);
 173
 174         rc = afb_evt_event_x2_add_watch(wreq->stubws->listener, event);
 175         if (rc >= 0)
 176                 rc = afb_proto_ws_call_subscribe(wreq->call,  afb_evt_event_x2_fullname(event), afb_evt_event_x2_id(event));
 177         if (rc < 0)
 178                 ERROR("error while subscribing event");
 179         return rc;
 180 }
 181
 182 static int server_req_unsubscribe_cb(struct afb_xreq *xreq, struct afb_event_x2 *event)
 183 {
 184         int rc, rc2;
 185         struct server_req *wreq = CONTAINER_OF_XREQ(struct server_req, xreq);
 186
 187         rc = afb_proto_ws_call_unsubscribe(wreq->call,  afb_evt_event_x2_fullname(event), afb_evt_event_x2_id(event));
 188         rc2 = afb_evt_event_x2_remove_watch(wreq->stubws->listener, event);
 189         if (rc >= 0 && rc2 < 0)
 190                 rc = rc2;
 191         if (rc < 0)
 192                 ERROR("error while unsubscribing event");
 193         return rc;
 194 }
 195
 196 static const struct afb_xreq_query_itf server_req_xreq_itf = {
 197         .reply = server_req_reply_cb,
 198         .unref = server_req_destroy_cb,
 199         .subscribe = server_req_subscribe_cb,
 200         .unsubscribe = server_req_unsubscribe_cb
 201 };
 202
 203 /******************* client part **********************************/
 204
 205 /* destroy all events */
 206 static void client_drop_all_events(struct afb_stub_ws *stubws)
 207 {
 208         struct client_event *ev, *nxt;
 209
 210         nxt = __atomic_exchange_n(&stubws->events, NULL, __ATOMIC_RELAXED);
 211         while (nxt) {
 212                 ev = nxt;
 213                 nxt = ev->next;
 214                 afb_evt_event_x2_unref(ev->event);
 215                 free(ev);
 216         }
 217 }
 218
 219 /* search the event */
 220 static struct client_event *client_event_search(struct afb_stub_ws *stubws, uint32_t eventid, const char *name)
 221 {
 222         struct client_event *ev;
 223
 224         ev = stubws->events;
 225         while (ev != NULL && (ev->id != eventid || 0 != strcmp(afb_evt_event_x2_fullname(ev->event), name)))
 226                 ev = ev->next;
 227
 228         DEBUG("searching event %s[%d]: %s", name, eventid, ev ? "found" : "not found");
 229         return ev;
 230 }
 231
 232 static struct afb_proto_ws *client_get_proto(struct afb_stub_ws *stubws)
 233 {
 234         struct fdev *fdev;
 235         struct afb_proto_ws *proto;
 236
 237         proto = stubws->proto;
 238         if (proto == NULL && stubws->robust.reopen) {
 239                 fdev = stubws->robust.reopen(stubws->robust.closure);
 240                 if (fdev != NULL)
 241                         proto = afb_stub_ws_create_proto(stubws, fdev, 0);
 242         }
 243         return proto;
 244 }
 245
 246 /* on call, propagate it to the ws service */
 247 static void client_api_call_cb(void * closure, struct afb_xreq *xreq)
 248 {
 249         int rc;
 250         struct afb_stub_ws *stubws = closure;
 251         struct afb_proto_ws *proto;
 252
 253         proto = client_get_proto(stubws);
 254         if (proto == NULL) {
 255                 afb_xreq_reply(xreq, NULL, "disconnected", "server hung up");
 256                 return;
 257         }
 258
 259         afb_xreq_unhooked_addref(xreq);
 260         rc = afb_proto_ws_client_call(
 261                         proto,
 262                         xreq->request.called_verb,
 263                         afb_xreq_json(xreq),
 264                         afb_session_uuid(xreq->context.session),
 265                         xreq,
 266                         xreq_on_behalf_cred_export(xreq));
 267         if (rc < 0) {
 268                 afb_xreq_reply(xreq, NULL, "internal", "can't send message");
 269                 afb_xreq_unhooked_unref(xreq);
 270         }
 271 }
 272
 273 /* get the description */
 274 static void client_api_describe_cb(void * closure, void (*describecb)(void *, struct json_object *), void *clocb)
 275 {
 276         struct afb_stub_ws *stubws = closure;
 277         struct afb_proto_ws *proto;
 278
 279         proto = client_get_proto(stubws);
 280         if (proto)
 281                 afb_proto_ws_client_describe(proto, describecb, clocb);
 282         else
 283                 describecb(clocb, NULL);
 284 }
 285
 286 /******************* server part: manage events **********************************/
 287
 288 static void server_event_add_cb(void *closure, const char *event, uint16_t eventid)
 289 {
 290         struct afb_stub_ws *stubws = closure;
 291
 292         if (stubws->proto != NULL)
 293                 afb_proto_ws_server_event_create(stubws->proto, event, eventid);
 294 }
 295
 296 static void server_event_remove_cb(void *closure, const char *event, uint16_t eventid)
 297 {
 298         struct afb_stub_ws *stubws = closure;
 299
 300         if (stubws->proto != NULL)
 301                 afb_proto_ws_server_event_remove(stubws->proto, event, eventid);
 302 }
 303
 304 static void server_event_push_cb(void *closure, const char *event, uint16_t eventid, struct json_object *object)
 305 {
 306         struct afb_stub_ws *stubws = closure;
 307
 308         if (stubws->proto != NULL)
 309                 afb_proto_ws_server_event_push(stubws->proto, event, eventid, object);
 310         json_object_put(object);
 311 }
 312
 313 static void server_event_broadcast_cb(void *closure, const char *event, struct json_object *object, const uuid_binary_t uuid, uint8_t hop)
 314 {
 315         struct afb_stub_ws *stubws = closure;
 316
 317         if (stubws->proto != NULL)
 318                 afb_proto_ws_server_event_broadcast(stubws->proto, event, object, uuid, hop);
 319         json_object_put(object);
 320 }
 321
 322 /*****************************************************/
 323
 324 static void client_on_reply_cb(void *closure, void *request, struct json_object *object, const char *error, const char *info)
 325 {
 326         struct afb_xreq *xreq = request;
 327
 328         afb_xreq_reply(xreq, object, error, info);
 329         afb_xreq_unhooked_unref(xreq);
 330 }
 331
 332 static void client_on_event_create_cb(void *closure, const char *event_name, int event_id)
 333 {
 334         struct afb_stub_ws *stubws = closure;
 335         struct client_event *ev;
 336
 337         /* check conflicts */
 338         ev = client_event_search(stubws, event_id, event_name);
 339         if (ev != NULL) {
 340                 __atomic_add_fetch(&ev->refcount, 1, __ATOMIC_RELAXED);
 341                 return;
 342         }
 343
 344         /* no conflict, try to add it */
 345         ev = malloc(sizeof *ev);
 346         if (ev != NULL) {
 347                 ev->event = afb_evt_event_x2_create(event_name);
 348                 if (ev->event != NULL) {
 349                         ev->refcount = 1;
 350                         ev->id = event_id;
 351                         ev->next = stubws->events;
 352                         stubws->events = ev;
 353                         return;
 354                 }
 355                 free(ev);
 356         }
 357         ERROR("can't create event %s, out of memory", event_name);
 358 }
 359
 360 static void client_on_event_remove_cb(void *closure, const char *event_name, int event_id)
 361 {
 362         struct afb_stub_ws *stubws = closure;
 363         struct client_event *ev, **prv;
 364
 365         /* check conflicts */
 366         ev = client_event_search(stubws, event_id, event_name);
 367         if (ev == NULL)
 368                 return;
 369
 370         /* decrease the reference count */
 371
 372         if (__atomic_sub_fetch(&ev->refcount, 1, __ATOMIC_RELAXED))
 373                 return;
 374
 375         /* unlinks the event */
 376         prv = &stubws->events;
 377         while (*prv != ev)
 378                 prv = &(*prv)->next;
 379         *prv = ev->next;
 380
 381         /* destroys the event */
 382         afb_evt_event_x2_unref(ev->event);
 383         free(ev);
 384 }
 385
 386 static void client_on_event_subscribe_cb(void *closure, void *request, const char *event_name, int event_id)
 387 {
 388         struct afb_stub_ws *stubws = closure;
 389         struct afb_xreq *xreq = request;
 390         struct client_event *ev;
 391
 392         /* check conflicts */
 393         ev = client_event_search(stubws, event_id, event_name);
 394         if (ev == NULL)
 395                 return;
 396
 397         if (afb_xreq_subscribe(xreq, ev->event) < 0)
 398                 ERROR("can't subscribe: %m");
 399 }
 400
 401 static void client_on_event_unsubscribe_cb(void *closure, void *request, const char *event_name, int event_id)
 402 {
 403         struct afb_stub_ws *stubws = closure;
 404         struct afb_xreq *xreq = request;
 405         struct client_event *ev;
 406
 407         /* check conflicts */
 408         ev = client_event_search(stubws, event_id, event_name);
 409         if (ev == NULL)
 410                 return;
 411
 412         if (afb_xreq_unsubscribe(xreq, ev->event) < 0)
 413                 ERROR("can't unsubscribe: %m");
 414 }
 415
 416 static void client_on_event_push_cb(void *closure, const char *event_name, int event_id, struct json_object *data)
 417 {
 418         struct afb_stub_ws *stubws = closure;
 419         struct client_event *ev;
 420
 421         /* check conflicts */
 422         ev = client_event_search(stubws, event_id, event_name);
 423         if (ev)
 424                 afb_evt_event_x2_push(ev->event, data);
 425         else
 426                 ERROR("unreadable push event");
 427 }
 428
 429 static void client_on_event_broadcast_cb(void *closure, const char *event_name, struct json_object *data, const uuid_binary_t uuid, uint8_t hop)
 430 {
 431         afb_evt_rebroadcast(event_name, data, uuid, hop);
 432 }
 433
 434 /*****************************************************/
 435
 436 static void server_record_session(struct afb_stub_ws *stubws, struct afb_session *session)
 437 {
 438         struct server_session *s, **prv;
 439
 440         /* search */
 441         prv = &stubws->sessions;
 442         while ((s = *prv)) {
 443                 if (s->session == session)
 444                         return;
 445                 if (afb_session_is_closed(s->session)) {
 446                         *prv = s->next;
 447                         afb_session_unref(s->session);
 448                         free(s);
 449                 }
 450                 else
 451                         prv = &s->next;
 452         }
 453
 454         /* create */
 455         s = malloc(sizeof *s);
 456         if (s) {
 457                 s->session = afb_session_addref(session);
 458                 s->next = stubws->sessions;
 459                 stubws->sessions = s;
 460         }
 461 }
 462
 463 static void server_release_all_sessions(struct afb_stub_ws *stubws)
 464 {
 465         struct server_session *ses, *nses;
 466
 467         nses = __atomic_exchange_n(&stubws->sessions, NULL, __ATOMIC_RELAXED);
 468         while(nses) {
 469                 ses = nses;
 470                 nses = ses->next;
 471                 afb_session_unref(ses->session);
 472                 free(ses);
 473         }
 474 }
 475
 476 /*****************************************************/
 477
 478 static void server_on_call_cb(void *closure, struct afb_proto_ws_call *call, const char *verb, struct json_object *args, const char *sessionid, const char *user_creds)
 479 {
 480         struct afb_stub_ws *stubws = closure;
 481         struct server_req *wreq;
 482
 483         afb_stub_ws_addref(stubws);
 484
 485         /* create the request */
 486         wreq = malloc(sizeof *wreq);
 487         if (wreq == NULL)
 488                 goto out_of_memory;
 489
 490         afb_xreq_init(&wreq->xreq, &server_req_xreq_itf);
 491         wreq->stubws = stubws;
 492         wreq->call = call;
 493
 494         /* init the context */
 495         if (afb_context_connect_validated(&wreq->xreq.context, sessionid) < 0)
 496                 goto unconnected;
 497         server_record_session(stubws, wreq->xreq.context.session);
 498         if (wreq->xreq.context.created)
 499                 afb_session_set_autoclose(wreq->xreq.context.session, 1);
 500
 501         /* makes the call */
 502         wreq->xreq.cred = afb_cred_mixed_on_behalf_import(stubws->cred, &wreq->xreq.context, user_creds);
 503         wreq->xreq.request.called_api = stubws->apiname;
 504         wreq->xreq.request.called_verb = verb;
 505         wreq->xreq.json = args;
 506         afb_xreq_process(&wreq->xreq, stubws->apiset);
 507         return;
 508
 509 unconnected:
 510         free(wreq);
 511 out_of_memory:
 512         json_object_put(args);
 513         afb_stub_ws_unref(stubws);
 514         afb_proto_ws_call_reply(call, NULL, "internal-error", NULL);
 515         afb_proto_ws_call_unref(call);
 516 }
 517
 518 static void server_on_description_cb(void *closure, struct json_object *description)
 519 {
 520         struct afb_proto_ws_describe *describe = closure;
 521         afb_proto_ws_describe_put(describe, description);
 522         json_object_put(description);
 523 }
 524
 525
 526 static void server_on_describe_cb(void *closure, struct afb_proto_ws_describe *describe)
 527 {
 528         struct afb_stub_ws *stubws = closure;
 529
 530         afb_apiset_describe(stubws->apiset, stubws->apiname, server_on_description_cb, describe);
 531 }
 532
 533 /*****************************************************/
 534
 535 static const struct afb_proto_ws_client_itf client_itf =
 536 {
 537         .on_reply = client_on_reply_cb,
 538         .on_event_create = client_on_event_create_cb,
 539         .on_event_remove = client_on_event_remove_cb,
 540         .on_event_subscribe = client_on_event_subscribe_cb,
 541         .on_event_unsubscribe = client_on_event_unsubscribe_cb,
 542         .on_event_push = client_on_event_push_cb,
 543         .on_event_broadcast = client_on_event_broadcast_cb,
 544 };
 545
 546 static struct afb_api_itf client_api_itf = {
 547         .call = client_api_call_cb,
 548         .describe = client_api_describe_cb
 549 };
 550
 551 static const struct afb_proto_ws_server_itf server_itf =
 552 {
 553         .on_call = server_on_call_cb,
 554         .on_describe = server_on_describe_cb
 555 };
 556
 557 /* the interface for events pushing */
 558 static const struct afb_evt_itf server_event_itf = {
 559         .broadcast = server_event_broadcast_cb,
 560         .push = server_event_push_cb,
 561         .add = server_event_add_cb,
 562         .remove = server_event_remove_cb
 563 };
 564
 565 /*****************************************************/
 566
 567 /* disconnect */
 568 static void disconnect(struct afb_stub_ws *stubws)
 569 {
 570         afb_proto_ws_unref(__atomic_exchange_n(&stubws->proto, NULL, __ATOMIC_RELAXED));
 571         if (stubws->is_client)
 572                 client_drop_all_events(stubws);
 573         else {
 574                 afb_evt_listener_unref(__atomic_exchange_n(&stubws->listener, NULL, __ATOMIC_RELAXED));
 575                 afb_cred_unref(__atomic_exchange_n(&stubws->cred, NULL, __ATOMIC_RELAXED));
 576                 server_release_all_sessions(stubws);
 577         }
 578 }
 579
 580
 581 /* callback when receiving a hangup */
 582 static void on_hangup(void *closure)
 583 {
 584         struct afb_stub_ws *stubws = closure;
 585
 586         if (stubws->proto) {
 587                 afb_stub_ws_addref(stubws);
 588                 disconnect(stubws);
 589                 if (stubws->on_hangup)
 590                         stubws->on_hangup(stubws);
 591                 afb_stub_ws_unref(stubws);
 592         }
 593 }
 594
 595 static int enqueue_processing(struct afb_proto_ws *proto, void (*callback)(int signum, void* arg), void *arg)
 596 {
 597         return jobs_queue(proto, 0, callback, arg);
 598 }
 599
 600 /*****************************************************/
 601
 602 static struct afb_proto_ws *afb_stub_ws_create_proto(struct afb_stub_ws *stubws, struct fdev *fdev, uint8_t is_client)
 603 {
 604         struct afb_proto_ws *proto;
 605
 606         stubws->proto = proto = is_client
 607                   ? afb_proto_ws_create_client(fdev, &client_itf, stubws)
 608                   : afb_proto_ws_create_server(fdev, &server_itf, stubws);
 609         if (proto) {
 610                 afb_proto_ws_on_hangup(proto, on_hangup);
 611                 afb_proto_ws_set_queuing(proto, enqueue_processing);
 612         }
 613
 614         return proto;
 615 }
 616
 617 static struct afb_stub_ws *afb_stub_ws_create(struct fdev *fdev, const char *apiname, struct afb_apiset *apiset, uint8_t is_client)
 618 {
 619         struct afb_stub_ws *stubws;
 620
 621         stubws = calloc(1, sizeof *stubws + 1 + strlen(apiname));
 622         if (stubws == NULL)
 623                 errno = ENOMEM;
 624         else {
 625                 if (afb_stub_ws_create_proto(stubws, fdev, is_client)) {
 626                         stubws->refcount = 1;
 627                         stubws->is_client = is_client;
 628                         strcpy(stubws->apiname, apiname);
 629                         stubws->apiset = afb_apiset_addref(apiset);
 630                         return stubws;
 631                 }
 632                 free(stubws);
 633         }
 634         fdev_unref(fdev);
 635         return NULL;
 636 }
 637
 638 struct afb_stub_ws *afb_stub_ws_create_client(struct fdev *fdev, const char *apiname, struct afb_apiset *apiset)
 639 {
 640         return afb_stub_ws_create(fdev, apiname, apiset, 1);
 641 }
 642
 643 struct afb_stub_ws *afb_stub_ws_create_server(struct fdev *fdev, const char *apiname, struct afb_apiset *apiset)
 644 {
 645         struct afb_stub_ws *stubws;
 646
 647         stubws = afb_stub_ws_create(fdev, apiname, apiset, 0);
 648         if (stubws) {
 649                 stubws->cred = afb_cred_create_for_socket(fdev_fd(fdev));
 650                 stubws->listener = afb_evt_listener_create(&server_event_itf, stubws);
 651                 if (stubws->listener != NULL)
 652                         return stubws;
 653                 afb_stub_ws_unref(stubws);
 654         }
 655         return NULL;
 656 }
 657
 658 void afb_stub_ws_unref(struct afb_stub_ws *stubws)
 659 {
 660         if (stubws && !__atomic_sub_fetch(&stubws->refcount, 1, __ATOMIC_RELAXED)) {
 661
 662                 if (stubws->is_client) {
 663                         stubws->robust.reopen = NULL;
 664                         if (stubws->robust.release)
 665                                 stubws->robust.release(stubws->robust.closure);
 666                 }
 667
 668                 disconnect(stubws);
 669                 afb_apiset_unref(stubws->apiset);
 670                 free(stubws);
 671         }
 672 }
 673
 674 void afb_stub_ws_addref(struct afb_stub_ws *stubws)
 675 {
 676         __atomic_add_fetch(&stubws->refcount, 1, __ATOMIC_RELAXED);
 677 }
 678
 679 void afb_stub_ws_set_on_hangup(struct afb_stub_ws *stubws, void (*on_hangup)(struct afb_stub_ws*))
 680 {
 681         stubws->on_hangup = on_hangup;
 682 }
 683
 684 const char *afb_stub_ws_name(struct afb_stub_ws *stubws)
 685 {
 686         return stubws->apiname;
 687 }
 688
 689 struct afb_api_item afb_stub_ws_client_api(struct afb_stub_ws *stubws)
 690 {
 691         struct afb_api_item api;
 692
 693         assert(stubws->is_client); /* check client */
 694         api.closure = stubws;
 695         api.itf = &client_api_itf;
 696         api.group = stubws; /* serialize for reconnections */
 697         return api;
 698 }
 699
 700 int afb_stub_ws_client_add(struct afb_stub_ws *stubws, struct afb_apiset *apiset)
 701 {
 702         return afb_apiset_add(apiset, stubws->apiname, afb_stub_ws_client_api(stubws));
 703 }
 704
 705 void afb_stub_ws_client_robustify(struct afb_stub_ws *stubws, struct fdev *(*reopen)(void*), void *closure, void (*release)(void*))
 706 {
 707         assert(stubws->is_client); /* check client */
 708
 709         if (stubws->robust.release)
 710                 stubws->robust.release(stubws->robust.closure);
 711
 712         stubws->robust.reopen = reopen;
 713         stubws->robust.closure = closure;
 714         stubws->robust.release = release;
 715 }