src/afb-api-ws.c

   1 /*
   2  * Copyright (C) 2015, 2016, 2017 "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 #define NO_PLUGIN_VERBOSE_MACRO
  20
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include <assert.h>
  24 #include <fcntl.h>
  25 #include <unistd.h>
  26 #include <errno.h>
  27 #include <endian.h>
  28 #include <netdb.h>
  29 #include <sys/types.h>
  30 #include <sys/socket.h>
  31 #include <sys/un.h>
  32
  33 #include <json-c/json.h>
  34 #include <systemd/sd-event.h>
  35
  36 #include <afb/afb-req-itf.h>
  37
  38 #include "afb-common.h"
  39
  40 #include "afb-session.h"
  41 #include "afb-ws.h"
  42 #include "afb-msg-json.h"
  43 #include "afb-apis.h"
  44 #include "afb-api-so.h"
  45 #include "afb-context.h"
  46 #include "afb-evt.h"
  47 #include "afb-subcall.h"
  48 #include "verbose.h"
  49 #include "sd-fds.h"
  50
  51 struct api_ws_memo;
  52 struct api_ws_event;
  53 struct api_ws_client;
  54
  55
  56
  57 /*
  58  */
  59 struct api_ws
  60 {
  61         char *path;             /* path of the object for the API */
  62         char *api;              /* api name of the interface */
  63         int fd;                 /* file descriptor */
  64         union {
  65                 struct {
  66                         uint32_t id;
  67                         struct afb_ws *ws;
  68                         struct api_ws_event *events;
  69                         struct api_ws_memo *memos;
  70                 } client;
  71                 struct {
  72                         sd_event_source *listensrc;
  73                         struct afb_evt_listener *listener; /* listener for broadcasted events */
  74                 } server;
  75         };
  76 };
  77
  78 #define RETOK   1
  79 #define RETERR  2
  80 #define RETRAW  3
  81
  82 /******************* websocket interface for client part **********************************/
  83
  84 static void api_ws_client_on_binary(void *closure, char *data, size_t size);
  85
  86 static const struct afb_ws_itf api_ws_client_ws_itf =
  87 {
  88         .on_close = NULL,
  89         .on_text = NULL,
  90         .on_binary = api_ws_client_on_binary,
  91         .on_error = NULL,
  92         .on_hangup = NULL
  93 };
  94
  95 /******************* event structures for server part **********************************/
  96
  97 static void api_ws_server_event_add(void *closure, const char *event, int eventid);
  98 static void api_ws_server_event_remove(void *closure, const char *event, int eventid);
  99 static void api_ws_server_event_push(void *closure, const char *event, int eventid, struct json_object *object);
 100 static void api_ws_server_event_broadcast(void *closure, const char *event, int eventid, struct json_object *object);
 101
 102 /* the interface for events pushing */
 103 static const struct afb_evt_itf api_ws_server_evt_itf = {
 104         .broadcast = api_ws_server_event_broadcast,
 105         .push = api_ws_server_event_push,
 106         .add = api_ws_server_event_add,
 107         .remove = api_ws_server_event_remove
 108 };
 109
 110 /******************* client description part for server *****************************/
 111
 112 struct api_ws_client
 113 {
 114         /* the server ws-api */
 115         const char *api;
 116
 117         /* count of references */
 118         int refcount;
 119
 120         /* listener for events */
 121         struct afb_evt_listener *listener;
 122
 123         /* file descriptor */
 124         int fd;
 125
 126         /* websocket */
 127         struct afb_ws *ws;
 128 };
 129
 130 /******************* websocket interface for client part **********************************/
 131
 132 static void api_ws_server_on_binary(void *closure, char *data, size_t size);
 133 static void api_ws_server_on_hangup(void *closure);
 134
 135 static const struct afb_ws_itf api_ws_server_ws_itf =
 136 {
 137         .on_close = NULL,
 138         .on_text = NULL,
 139         .on_binary = api_ws_server_on_binary,
 140         .on_error = NULL,
 141         .on_hangup = api_ws_server_on_hangup
 142 };
 143
 144 /******************* ws request part for server *****************/
 145
 146 /*
 147  * structure for a ws request
 148  */
 149 struct api_ws_server_req {
 150         struct afb_context context;     /* the context, should be THE FIRST */
 151         struct api_ws_client *client;   /* the client of the request */
 152         char *rcvdata;                  /* the received data to free */
 153         struct json_object *json;       /* the readen request as object */
 154         const char *request;            /* the readen request as string */
 155         size_t lenreq;                  /* the length of the request */
 156         int refcount;                   /* reference count of the request */
 157         uint32_t msgid;                 /* the incoming request msgid */
 158 };
 159
 160 static struct json_object *api_ws_server_req_json(struct api_ws_server_req *wreq);
 161 static void api_ws_server_req_unref(struct api_ws_server_req *wreq);
 162
 163 static struct json_object *api_ws_server_req_json_cb(void *closure);
 164 static struct afb_arg api_ws_server_req_get_cb(void *closure, const char *name);
 165 static void api_ws_server_req_success_cb(void *closure, struct json_object *obj, const char *info);
 166 static void api_ws_server_req_fail_cb(void *closure, const char *status, const char *info);
 167 static const char *api_ws_server_req_raw_cb(void *closure, size_t *size);
 168 static void api_ws_server_req_send_cb(void *closure, const char *buffer, size_t size);
 169 static void api_ws_server_req_addref_cb(void *closure);
 170 static void api_ws_server_req_unref_cb(void *closure);
 171 static int api_ws_server_req_subscribe_cb(void *closure, struct afb_event event);
 172 static int api_ws_server_req_unsubscribe_cb(void *closure, struct afb_event event);
 173 static void api_ws_server_req_subcall_cb(void *closure, const char *api, const char *verb, struct json_object *args, void (*callback)(void*, int, struct json_object*), void *cb_closure);
 174
 175 const struct afb_req_itf afb_api_ws_req_itf = {
 176         .json = api_ws_server_req_json_cb,
 177         .get = api_ws_server_req_get_cb,
 178         .success = api_ws_server_req_success_cb,
 179         .fail = api_ws_server_req_fail_cb,
 180         .raw = api_ws_server_req_raw_cb,
 181         .send = api_ws_server_req_send_cb,
 182         .context_get = (void*)afb_context_get,
 183         .context_set = (void*)afb_context_set,
 184         .addref = api_ws_server_req_addref_cb,
 185         .unref = api_ws_server_req_unref_cb,
 186         .session_close = (void*)afb_context_close,
 187         .session_set_LOA = (void*)afb_context_change_loa,
 188         .subscribe = api_ws_server_req_subscribe_cb,
 189         .unsubscribe = api_ws_server_req_unsubscribe_cb,
 190         .subcall = api_ws_server_req_subcall_cb
 191 };
 192
 193 /******************* common part **********************************/
 194
 195 /*
 196  * create a structure api_ws not connected to the 'path'.
 197  */
 198 static struct api_ws *api_ws_make(const char *path)
 199 {
 200         struct api_ws *api;
 201         size_t length;
 202
 203         /* allocates the structure */
 204         length = strlen(path);
 205         api = calloc(1, sizeof *api + 1 + length);
 206         if (api == NULL) {
 207                 errno = ENOMEM;
 208                 goto error;
 209         }
 210
 211         /* path is copied after the struct */
 212         api->path = (char*)(api+1);
 213         memcpy(api->path, path, length + 1);
 214
 215         /* api name is at the end of the path */
 216         while (length && path[length - 1] != '/' && path[length - 1] != ':')
 217                 length = length - 1;
 218         api->api = &api->path[length];
 219         if (api->api == NULL || !afb_apis_is_valid_api_name(++api->api)) {
 220                 errno = EINVAL;
 221                 goto error2;
 222         }
 223
 224         api->fd = -1;
 225         return api;
 226
 227 error2:
 228         free(api);
 229 error:
 230         return NULL;
 231 }
 232
 233 static int api_ws_socket_unix(const char *path, int server)
 234 {
 235         int fd, rc;
 236         struct sockaddr_un addr;
 237         size_t length;
 238
 239         length = strlen(path);
 240         if (length >= 108) {
 241                 errno = ENAMETOOLONG;
 242                 return -1;
 243         }
 244
 245         if (server)
 246                 unlink(path);
 247
 248         fd = socket(AF_UNIX, SOCK_STREAM, 0);
 249         if (fd < 0)
 250                 return fd;
 251
 252         memset(&addr, 0, sizeof addr);
 253         addr.sun_family = AF_UNIX;
 254         strcpy(addr.sun_path, path);
 255         if (server) {
 256                 rc = bind(fd, (struct sockaddr *) &addr, (socklen_t)(sizeof addr));
 257         } else {
 258                 rc = connect(fd, (struct sockaddr *) &addr, (socklen_t)(sizeof addr));
 259         }
 260         if (rc < 0) {
 261                 close(fd);
 262                 return rc;
 263         }
 264         return fd;
 265 }
 266
 267 static int api_ws_socket_inet(const char *path, int server)
 268 {
 269         int rc, fd;
 270         const char *service, *host, *api;
 271         struct addrinfo hint, *rai, *iai;
 272
 273         /* scan the uri */
 274         api = strrchr(path, '/');
 275         service = strrchr(path, ':');
 276         if (api == NULL || service == NULL || api < service) {
 277                 errno = EINVAL;
 278                 return -1;
 279         }
 280         host = strndupa(path, service++ - path);
 281         service = strndupa(service, api - service);
 282
 283         /* get addr */
 284         memset(&hint, 0, sizeof hint);
 285         hint.ai_family = AF_INET;
 286         hint.ai_socktype = SOCK_STREAM;
 287         rc = getaddrinfo(host, service, &hint, &rai);
 288         if (rc != 0) {
 289                 errno = EINVAL;
 290                 return -1;
 291         }
 292
 293         /* get the socket */
 294         iai = rai;
 295         while (iai != NULL) {
 296                 fd = socket(iai->ai_family, iai->ai_socktype, iai->ai_protocol);
 297                 if (fd >= 0) {
 298                         if (server) {
 299                                 rc = bind(fd, iai->ai_addr, iai->ai_addrlen);
 300                         } else {
 301                                 rc = connect(fd, iai->ai_addr, iai->ai_addrlen);
 302                         }
 303                         if (rc == 0) {
 304                                 freeaddrinfo(rai);
 305                                 return fd;
 306                         }
 307                         close(fd);
 308                 }
 309                 iai = iai->ai_next;
 310         }
 311         freeaddrinfo(rai);
 312         return -1;
 313
 314 }
 315
 316 static int api_ws_socket(const char *path, int server)
 317 {
 318         int fd, rc;
 319
 320         /* check for systemd socket */
 321         if (0 == strncmp(path, "sd:", 3))
 322                 fd = sd_fds_for(path + 3);
 323         else {
 324                 /* check for unix socket */
 325                 if (0 == strncmp(path, "unix:", 5))
 326                         /* unix socket */
 327                         fd = api_ws_socket_unix(path + 5, server);
 328                 else
 329                         /* inet socket */
 330                         fd = api_ws_socket_inet(path, server);
 331
 332                 if (fd >= 0 && server) {
 333                         rc = 1;
 334                         setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &rc, sizeof rc);
 335                         rc = listen(fd, 5);
 336                 }
 337         }
 338         /* configure the socket */
 339         if (fd >= 0) {
 340                 fcntl(fd, F_SETFD, FD_CLOEXEC);
 341                 fcntl(fd, F_SETFL, O_NONBLOCK);
 342         }
 343         return fd;
 344 }
 345
 346 /******************* serialisation part **********************************/
 347
 348 struct readbuf
 349 {
 350         char *head, *end;
 351 };
 352
 353 #define WRITEBUF_COUNT_MAX  32
 354 struct writebuf
 355 {
 356         struct iovec iovec[WRITEBUF_COUNT_MAX];
 357         uint32_t uints[WRITEBUF_COUNT_MAX];
 358         int count;
 359 };
 360
 361 static char *api_ws_read_get(struct readbuf *rb, uint32_t length)
 362 {
 363         char *before = rb->head;
 364         char *after = before + length;
 365         if (after > rb->end)
 366                 return 0;
 367         rb->head = after;
 368         return before;
 369 }
 370
 371 static int api_ws_read_uint32(struct readbuf *rb, uint32_t *value)
 372 {
 373         char *after = rb->head + sizeof *value;
 374         if (after > rb->end)
 375                 return 0;
 376         memcpy(value, rb->head, sizeof *value);
 377         rb->head = after;
 378         *value = le32toh(*value);
 379         return 1;
 380 }
 381
 382 static int api_ws_read_string(struct readbuf *rb, const char **value, size_t *length)
 383 {
 384         uint32_t len;
 385         if (!api_ws_read_uint32(rb, &len) || !len)
 386                 return 0;
 387         if (length)
 388                 *length = (size_t)(len - 1);
 389         return (*value = api_ws_read_get(rb, len)) != NULL &&  rb->head[-1] == 0;
 390 }
 391
 392 static int api_ws_read_object(struct readbuf *rb, struct json_object **object)
 393 {
 394         size_t length;
 395         const char *string;
 396         return api_ws_read_string(rb, &string, &length) && ((*object = json_tokener_parse(string)) != NULL) == (strcmp(string, "null") != 0);
 397 }
 398
 399 static int api_ws_write_put(struct writebuf *wb, const void *value, size_t length)
 400 {
 401         int i = wb->count;
 402         if (i == WRITEBUF_COUNT_MAX)
 403                 return 0;
 404         wb->iovec[i].iov_base = (void*)value;
 405         wb->iovec[i].iov_len = length;
 406         wb->count = i + 1;
 407         return 1;
 408 }
 409
 410 static int api_ws_write_char(struct writebuf *wb, char value)
 411 {
 412         int i = wb->count;
 413         if (i == WRITEBUF_COUNT_MAX)
 414                 return 0;
 415         *(char*)&wb->uints[i] = value;
 416         wb->iovec[i].iov_base = &wb->uints[i];
 417         wb->iovec[i].iov_len = 1;
 418         wb->count = i + 1;
 419         return 1;
 420 }
 421
 422 static int api_ws_write_uint32(struct writebuf *wb, uint32_t value)
 423 {
 424         int i = wb->count;
 425         if (i == WRITEBUF_COUNT_MAX)
 426                 return 0;
 427         wb->uints[i] = htole32(value);
 428         wb->iovec[i].iov_base = &wb->uints[i];
 429         wb->iovec[i].iov_len = sizeof wb->uints[i];
 430         wb->count = i + 1;
 431         return 1;
 432 }
 433
 434 static int api_ws_write_string_length(struct writebuf *wb, const char *value, size_t length)
 435 {
 436         uint32_t len = (uint32_t)++length;
 437         return (size_t)len == length && len && api_ws_write_uint32(wb, len) && api_ws_write_put(wb, value, length);
 438 }
 439
 440 static int api_ws_write_string(struct writebuf *wb, const char *value)
 441 {
 442         return api_ws_write_string_length(wb, value, strlen(value));
 443 }
 444
 445 static int api_ws_write_object(struct writebuf *wb, struct json_object *object)
 446 {
 447         const char *string = json_object_to_json_string_ext(object, JSON_C_TO_STRING_PLAIN);
 448         return string != NULL && api_ws_write_string(wb, string);
 449 }
 450
 451
 452
 453
 454 /******************* client part **********************************/
 455
 456 /*
 457  * structure for recording query data
 458  */
 459 struct api_ws_memo {
 460         struct api_ws_memo *next;               /* the next memo */
 461         struct api_ws *api;             /* the ws api */
 462         struct afb_req req;             /* the request handle */
 463         struct afb_context *context;    /* the context of the query */
 464         uint32_t msgid;                 /* the message identifier */
 465 };
 466
 467 struct api_ws_event
 468 {
 469         struct api_ws_event *next;
 470         struct afb_event event;
 471         int eventid;
 472         int refcount;
 473 };
 474
 475 /* search a memorized request */
 476 static struct api_ws_memo *api_ws_client_memo_search(struct api_ws *api, uint32_t msgid)
 477 {
 478         struct api_ws_memo *memo;
 479
 480         memo = api->client.memos;
 481         while (memo != NULL && memo->msgid != msgid)
 482                 memo = memo->next;
 483
 484         return memo;
 485 }
 486
 487 /* search the event */
 488 static struct api_ws_event *api_ws_client_event_search(struct api_ws *api, uint32_t eventid, const char *name)
 489 {
 490         struct api_ws_event *ev;
 491
 492         ev = api->client.events;
 493         while (ev != NULL && (ev->eventid != eventid || 0 != strcmp(afb_evt_event_name(ev->event), name)))
 494                 ev = ev->next;
 495
 496         return ev;
 497 }
 498
 499
 500 /* allocates and init the memorizing data */
 501 static struct api_ws_memo *api_ws_client_memo_make(struct api_ws *api, struct afb_req req, struct afb_context *context)
 502 {
 503         struct api_ws_memo *memo;
 504
 505         memo = malloc(sizeof *memo);
 506         if (memo != NULL) {
 507                 afb_req_addref(req);
 508                 memo->req = req;
 509                 memo->context = context;
 510                 do { memo->msgid = ++api->client.id; } while(api_ws_client_memo_search(api, memo->msgid) != NULL);
 511                 memo->api = api;
 512                 memo->next = api->client.memos;
 513                 api->client.memos = memo;
 514         }
 515         return memo;
 516 }
 517
 518 /* free and release the memorizing data */
 519 static void api_ws_client_memo_destroy(struct api_ws_memo *memo)
 520 {
 521         struct api_ws_memo **prv;
 522
 523         prv = &memo->api->client.memos;
 524         while (*prv != NULL) {
 525                 if (*prv == memo) {
 526                         *prv = memo->next;
 527                         break;
 528                 }
 529                 prv = &(*prv)->next;
 530         }
 531
 532         afb_req_unref(memo->req);
 533         free(memo);
 534 }
 535
 536 /* get event data from the message */
 537 static int api_ws_client_msg_event_read(struct readbuf *rb, uint32_t *eventid, const char **name)
 538 {
 539         return api_ws_read_uint32(rb, eventid) && api_ws_read_string(rb, name, NULL);
 540 }
 541
 542 /* get event from the message */
 543 static int api_ws_client_msg_event_get(struct api_ws *api, struct readbuf *rb, struct api_ws_event **ev)
 544 {
 545         const char *name;
 546         uint32_t eventid;
 547
 548         /* get event data from the message */
 549         if (!api_ws_client_msg_event_read(rb, &eventid, &name)) {
 550                 ERROR("Invalid message");
 551                 return 0;
 552         }
 553
 554         /* check conflicts */
 555         *ev = api_ws_client_event_search(api, eventid, name);
 556         if (*ev == NULL) {
 557                 ERROR("event %s not found", name);
 558                 return 0;
 559         }
 560
 561         return 1;
 562 }
 563
 564 /* get event from the message */
 565 static int api_ws_client_msg_memo_get(struct api_ws *api, struct readbuf *rb, struct api_ws_memo **memo)
 566 {
 567         uint32_t msgid;
 568
 569         /* get event data from the message */
 570         if (!api_ws_read_uint32(rb, &msgid)) {
 571                 ERROR("Invalid message");
 572                 return 0;
 573         }
 574
 575         /* get the memo */
 576         *memo = api_ws_client_memo_search(api, msgid);
 577         if (*memo == NULL) {
 578                 ERROR("message not found");
 579                 return 0;
 580         }
 581
 582         return 1;
 583 }
 584
 585 /* read a subscrition message */
 586 static int api_ws_client_msg_subscription_get(struct api_ws *api, struct readbuf *rb, struct api_ws_event **ev, struct api_ws_memo **memo)
 587 {
 588         return api_ws_client_msg_memo_get(api, rb, memo) && api_ws_client_msg_event_get(api, rb, ev);
 589 }
 590
 591 /* adds an event */
 592 static void api_ws_client_event_create(struct api_ws *api, struct readbuf *rb)
 593 {
 594         size_t offset;
 595         const char *name;
 596         uint32_t eventid;
 597         struct api_ws_event *ev;
 598
 599         /* get event data from the message */
 600         offset = api_ws_client_msg_event_read(rb, &eventid, &name);
 601         if (offset == 0) {
 602                 ERROR("Invalid message");
 603                 return;
 604         }
 605
 606         /* check conflicts */
 607         ev = api_ws_client_event_search(api, eventid, name);
 608         if (ev != NULL) {
 609                 ev->refcount++;
 610                 return;
 611         }
 612
 613         /* no conflict, try to add it */
 614         ev = malloc(sizeof *ev);
 615         if (ev != NULL) {
 616                 ev->event = afb_evt_create_event(name);
 617                 if (ev->event.closure == NULL)
 618                         free(ev);
 619                 else {
 620                         ev->refcount = 1;
 621                         ev->eventid = eventid;
 622                         ev->next = api->client.events;
 623                         api->client.events = ev;
 624                         return;
 625                 }
 626         }
 627         ERROR("can't create event %s, out of memory", name);
 628 }
 629
 630 /* removes an event */
 631 static void api_ws_client_event_drop(struct api_ws *api, struct readbuf *rb)
 632 {
 633         struct api_ws_event *ev, **prv;
 634
 635         /* retrieves the event */
 636         if (!api_ws_client_msg_event_get(api, rb, &ev))
 637                 return;
 638
 639         /* decrease the reference count */
 640         if (--ev->refcount)
 641                 return;
 642
 643         /* unlinks the event */
 644         prv = &api->client.events;
 645         while (*prv != ev)
 646                 prv = &(*prv)->next;
 647         *prv = ev->next;
 648
 649         /* destroys the event */
 650         afb_event_drop(ev->event);
 651         free(ev);
 652 }
 653
 654 /* subscribes an event */
 655 static void api_ws_client_event_subscribe(struct api_ws *api, struct readbuf *rb)
 656 {
 657         struct api_ws_event *ev;
 658         struct api_ws_memo *memo;
 659
 660         if (api_ws_client_msg_subscription_get(api, rb, &ev, &memo)) {
 661                 /* subscribe the request from the event */
 662                 if (afb_req_subscribe(memo->req, ev->event) < 0)
 663                         ERROR("can't subscribe: %m");
 664         }
 665 }
 666
 667 /* unsubscribes an event */
 668 static void api_ws_client_event_unsubscribe(struct api_ws *api, struct readbuf *rb)
 669 {
 670         struct api_ws_event *ev;
 671         struct api_ws_memo *memo;
 672
 673         if (api_ws_client_msg_subscription_get(api, rb, &ev, &memo)) {
 674                 /* unsubscribe the request from the event */
 675                 if (afb_req_unsubscribe(memo->req, ev->event) < 0)
 676                         ERROR("can't unsubscribe: %m");
 677         }
 678 }
 679
 680 /* receives broadcasted events */
 681 static void api_ws_client_event_broadcast(struct api_ws *api, struct readbuf *rb)
 682 {
 683         struct json_object *object;
 684         const char *event;
 685
 686         if (api_ws_read_string(rb, &event, NULL) && api_ws_read_object(rb, &object))
 687                 afb_evt_broadcast(event, object);
 688         else
 689                 ERROR("unreadable broadcasted event");
 690 }
 691
 692 /* pushs an event */
 693 static void api_ws_client_event_push(struct api_ws *api, struct readbuf *rb)
 694 {
 695         struct api_ws_event *ev;
 696         struct json_object *object;
 697
 698         if (api_ws_client_msg_event_get(api, rb, &ev) && api_ws_read_object(rb, &object))
 699                 afb_event_push(ev->event, object);
 700         else
 701                 ERROR("unreadable push event");
 702 }
 703
 704 static void api_ws_client_reply_success(struct api_ws *api, struct readbuf *rb)
 705 {
 706         struct api_ws_memo *memo;
 707         struct json_object *object;
 708         const char *info;
 709         uint32_t flags;
 710
 711         /* retrieve the message data */
 712         if (!api_ws_client_msg_memo_get(api, rb, &memo))
 713                 return;
 714
 715         if (api_ws_read_uint32(rb, &flags)
 716          && api_ws_read_string(rb, &info, NULL)
 717          && api_ws_read_object(rb, &object)) {
 718                 memo->context->flags = (unsigned)flags;
 719                 afb_req_success(memo->req, object, *info ? info : NULL);
 720         } else {
 721                 /* failing to have the answer */
 722                 afb_req_fail(memo->req, "error", "ws error");
 723         }
 724         api_ws_client_memo_destroy(memo);
 725 }
 726
 727 static void api_ws_client_reply_fail(struct api_ws *api, struct readbuf *rb)
 728 {
 729         struct api_ws_memo *memo;
 730         const char *info, *status;
 731         uint32_t flags;
 732
 733         /* retrieve the message data */
 734         if (!api_ws_client_msg_memo_get(api, rb, &memo))
 735                 return;
 736
 737         if (api_ws_read_uint32(rb, &flags)
 738          && api_ws_read_string(rb, &status, NULL)
 739          && api_ws_read_string(rb, &info, NULL)) {
 740                 memo->context->flags = (unsigned)flags;
 741                 afb_req_fail(memo->req, status, *info ? info : NULL);
 742         } else {
 743                 /* failing to have the answer */
 744                 afb_req_fail(memo->req, "error", "ws error");
 745         }
 746         api_ws_client_memo_destroy(memo);
 747 }
 748
 749 static void api_ws_client_reply_send(struct api_ws *api, struct readbuf *rb)
 750 {
 751         struct api_ws_memo *memo;
 752         const char *data;
 753         size_t length;
 754         uint32_t flags;
 755
 756         /* retrieve the message data */
 757         if (!api_ws_client_msg_memo_get(api, rb, &memo))
 758                 return;
 759
 760         if (api_ws_read_uint32(rb, &flags)
 761          && api_ws_read_string(rb, &data, &length)) {
 762                 memo->context->flags = (unsigned)flags;
 763                 afb_req_send(memo->req, data, length);
 764         } else {
 765                 /* failing to have the answer */
 766                 afb_req_fail(memo->req, "error", "ws error");
 767         }
 768         api_ws_client_memo_destroy(memo);
 769 }
 770
 771 /* callback when receiving binary data */
 772 static void api_ws_client_on_binary(void *closure, char *data, size_t size)
 773 {
 774         if (size > 0) {
 775                 struct readbuf rb = { .head = data, .end = data + size };
 776                 switch (*rb.head++) {
 777                 case 'T': /* success */
 778                         api_ws_client_reply_success(closure, &rb);
 779                         break;
 780                 case 'F': /* fail */
 781                         api_ws_client_reply_fail(closure, &rb);
 782                         break;
 783                 case 'X': /* send */
 784                         api_ws_client_reply_send(closure, &rb);
 785                         break;
 786                 case '*': /* broadcast */
 787                         api_ws_client_event_broadcast(closure, &rb);
 788                         break;
 789                 case '+': /* creates the event */
 790                         api_ws_client_event_create(closure, &rb);
 791                         break;
 792                 case '-': /* drops the event */
 793                         api_ws_client_event_drop(closure, &rb);
 794                         break;
 795                 case '!': /* pushs the event */
 796                         api_ws_client_event_push(closure, &rb);
 797                         break;
 798                 case 'S': /* subscribe event for a request */
 799                         api_ws_client_event_subscribe(closure, &rb);
 800                         break;
 801                 case 'U': /* unsubscribe event for a request */
 802                         api_ws_client_event_unsubscribe(closure, &rb);
 803                         break;
 804                 default: /* unexpected message */
 805                         break;
 806                 }
 807         }
 808         free(data);
 809 }
 810
 811 /* on call, propagate it to the ws service */
 812 static void api_ws_client_call_cb(void * closure, struct afb_req req, struct afb_context *context, const char *verb)
 813 {
 814         int rc;
 815         struct api_ws_memo *memo;
 816         struct writebuf wb = { .count = 0 };
 817         const char *raw;
 818         size_t szraw;
 819         struct api_ws *api = closure;
 820
 821         /* create the recording data */
 822         memo = api_ws_client_memo_make(api, req, context);
 823         if (memo == NULL) {
 824                 afb_req_fail(req, "error", "out of memory");
 825                 return;
 826         }
 827
 828         /* creates the call message */
 829         raw = afb_req_raw(req, &szraw);
 830         if (raw == NULL)
 831                 goto internal_error;
 832         if (!api_ws_write_uint32(&wb, memo->msgid)
 833          || !api_ws_write_uint32(&wb, (uint32_t)context->flags)
 834          || !api_ws_write_string(&wb, verb)
 835          || !api_ws_write_string(&wb, afb_session_uuid(context->session))
 836          || !api_ws_write_string_length(&wb, raw, szraw))
 837                 goto overflow;
 838
 839         /* send */
 840         rc = afb_ws_binary_v(api->client.ws, wb.iovec, wb.count);
 841         if (rc < 0)
 842                 goto ws_send_error;
 843         return;
 844
 845 ws_send_error:
 846         afb_req_fail(req, "error", "websocket sending error");
 847         goto clean_memo;
 848
 849 internal_error:
 850         afb_req_fail(req, "error", "internal: raw is NULL!");
 851         goto clean_memo;
 852
 853 overflow:
 854         afb_req_fail(req, "error", "overflow: size doesn't match 32 bits!");
 855
 856 clean_memo:
 857         api_ws_client_memo_destroy(memo);
 858 }
 859
 860 static int api_ws_service_start_cb(void *closure, int share_session, int onneed)
 861 {
 862         struct api_ws *api = closure;
 863
 864         /* not an error when onneed */
 865         if (onneed != 0)
 866                 return 0;
 867
 868         /* already started: it is an error */
 869         ERROR("The WS binding %s is not a startable service", api->path);
 870         return -1;
 871 }
 872
 873 /*  */
 874 static void api_ws_client_disconnect(struct api_ws *api)
 875 {
 876         if (api->fd >= 0) {
 877                 afb_ws_destroy(api->client.ws);
 878                 api->client.ws = NULL;
 879                 close(api->fd);
 880                 api->fd = -1;
 881         }
 882 }
 883
 884 /*  */
 885 static int api_ws_client_connect(struct api_ws *api)
 886 {
 887         struct afb_ws *ws;
 888         int fd;
 889
 890         fd = api_ws_socket(api->path, 0);
 891         if (fd >= 0) {
 892                 ws = afb_ws_create(afb_common_get_event_loop(), fd, &api_ws_client_ws_itf, api);
 893                 if (ws != NULL) {
 894                         api->client.ws = ws;
 895                         api->fd = fd;
 896                         return 0;
 897                 }
 898                 close(fd);
 899         }
 900         return -1;
 901 }
 902
 903 /* adds a afb-ws-service client api */
 904 int afb_api_ws_add_client(const char *path)
 905 {
 906         int rc;
 907         struct api_ws *api;
 908         struct afb_api afb_api;
 909
 910         /* create the ws client api */
 911         api = api_ws_make(path);
 912         if (api == NULL)
 913                 goto error;
 914
 915         /* connect to the service */
 916         rc = api_ws_client_connect(api);
 917         if (rc < 0) {
 918                 ERROR("can't connect to ws service %s", api->path);
 919                 goto error2;
 920         }
 921
 922         /* record it as an API */
 923         afb_api.closure = api;
 924         afb_api.call = api_ws_client_call_cb;
 925         afb_api.service_start = api_ws_service_start_cb;
 926         if (afb_apis_add(api->api, afb_api) < 0)
 927                 goto error3;
 928
 929         return 0;
 930
 931 error3:
 932         api_ws_client_disconnect(api);
 933 error2:
 934         free(api);
 935 error:
 936         return -1;
 937 }
 938
 939 /******************* client description part for server *****************************/
 940
 941 static void api_ws_server_client_unref(struct api_ws_client *client)
 942 {
 943         if (!--client->refcount) {
 944                 afb_evt_listener_unref(client->listener);
 945                 afb_ws_destroy(client->ws);
 946                 free(client);
 947         }
 948 }
 949
 950 /* on call, propagate it to the ws service */
 951 static void api_ws_server_called(struct api_ws_client *client, struct readbuf *rb, char *data, size_t size)
 952 {
 953         struct api_ws_server_req *wreq;
 954         struct afb_req areq;
 955         const char *uuid, *verb;
 956         uint32_t flags;
 957
 958         client->refcount++;
 959
 960         /* create the request */
 961         wreq = calloc(1 , sizeof *wreq);
 962         if (wreq == NULL)
 963                 goto out_of_memory;
 964
 965         wreq->client = client;
 966         wreq->rcvdata = data;
 967         wreq->refcount = 1;
 968
 969         /* reads the call message data */
 970         if (!api_ws_read_uint32(rb, &wreq->msgid)
 971          || !api_ws_read_uint32(rb, &flags)
 972          || !api_ws_read_string(rb, &verb, NULL)
 973          || !api_ws_read_string(rb, &uuid, NULL)
 974          || !api_ws_read_string(rb, &wreq->request, &wreq->lenreq))
 975                 goto overflow;
 976
 977         /* init the context */
 978         if (afb_context_connect(&wreq->context, uuid, NULL) < 0)
 979                 goto out_of_memory;
 980         wreq->context.flags = flags;
 981
 982         /* makes the call */
 983         areq.itf = &afb_api_ws_req_itf;
 984         areq.closure = wreq;
 985         afb_apis_call(areq, &wreq->context, client->api, verb);
 986         api_ws_server_req_unref(wreq);
 987         return;
 988
 989 out_of_memory:
 990 overflow:
 991         free(wreq);
 992         free(data);
 993         api_ws_server_client_unref(client);
 994 }
 995
 996 /* callback when receiving binary data */
 997 static void api_ws_server_on_binary(void *closure, char *data, size_t size)
 998 {
 999         struct readbuf rb = { .head = data, .end = data + size };
1000         api_ws_server_called(closure, &rb, data, size);
1001 }
1002
1003 /* callback when receiving a hangup */
1004 static void api_ws_server_on_hangup(void *closure)
1005 {
1006         struct api_ws_client *client = closure;
1007
1008         /* close the socket */
1009         if (client->fd >= 0) {
1010                 close(client->fd);
1011                 client->fd = -1;
1012         }
1013
1014         /* release the client */
1015         api_ws_server_client_unref(client);
1016 }
1017
1018 static void api_ws_server_accept(struct api_ws *api)
1019 {
1020         struct api_ws_client *client;
1021         struct sockaddr addr;
1022         socklen_t lenaddr;
1023
1024         client = calloc(1, sizeof *client);
1025         if (client != NULL) {
1026                 client->listener = afb_evt_listener_create(&api_ws_server_evt_itf, client);
1027                 if (client->listener != NULL) {
1028                         lenaddr = (socklen_t)sizeof addr;
1029                         client->fd = accept(api->fd, &addr, &lenaddr);
1030                         if (client->fd >= 0) {
1031                                 fcntl(client->fd, F_SETFD, FD_CLOEXEC);
1032                                 fcntl(client->fd, F_SETFL, O_NONBLOCK);
1033                                 client->ws = afb_ws_create(afb_common_get_event_loop(), client->fd, &api_ws_server_ws_itf, client);
1034                                 if (client->ws != NULL) {
1035                                         client->api = api->api;
1036                                         client->refcount = 1;
1037                                         return;
1038                                 }
1039                                 close(client->fd);
1040                         }
1041                         afb_evt_listener_unref(client->listener);
1042                 }
1043                 free(client);
1044         }
1045 }
1046
1047 /******************* server part: manage events **********************************/
1048
1049 static void api_ws_server_event_send(struct api_ws_client *client, char order, const char *event, int eventid, const char *data)
1050 {
1051         int rc;
1052         struct writebuf wb = { .count = 0 };
1053
1054         if (api_ws_write_char(&wb, order)
1055          && api_ws_write_uint32(&wb, eventid)
1056          && api_ws_write_string(&wb, event)
1057          && (data == NULL || api_ws_write_string(&wb, data))) {
1058                 rc = afb_ws_binary_v(client->ws, wb.iovec, wb.count);
1059                 if (rc >= 0)
1060                         return;
1061         }
1062         ERROR("error while sending %c for event %s", order, event);
1063 }
1064
1065 static void api_ws_server_event_add(void *closure, const char *event, int eventid)
1066 {
1067         api_ws_server_event_send(closure, '+', event, eventid, NULL);
1068 }
1069
1070 static void api_ws_server_event_remove(void *closure, const char *event, int eventid)
1071 {
1072         api_ws_server_event_send(closure, '-', event, eventid, NULL);
1073 }
1074
1075 static void api_ws_server_event_push(void *closure, const char *event, int eventid, struct json_object *object)
1076 {
1077         const char *data = json_object_to_json_string_ext(object, JSON_C_TO_STRING_PLAIN);
1078         api_ws_server_event_send(closure, '!', event, eventid, data ? : "null");
1079         json_object_put(object);
1080 }
1081
1082 static void api_ws_server_event_broadcast(void *closure, const char *event, int eventid, struct json_object *object)
1083 {
1084         int rc;
1085         struct api_ws_client *client = closure;
1086
1087         struct writebuf wb = { .count = 0 };
1088
1089         if (api_ws_write_char(&wb, '*') && api_ws_write_string(&wb, event) && api_ws_write_object(&wb, object)) {
1090                 rc = afb_ws_binary_v(client->ws, wb.iovec, wb.count);
1091                 if (rc < 0)
1092                         ERROR("error while broadcasting event %s", event);
1093         } else
1094                 ERROR("error while broadcasting event %s", event);
1095         json_object_put(object);
1096 }
1097
1098 /******************* ws request part for server *****************/
1099
1100 /* increment the reference count of the request */
1101 static void api_ws_server_req_addref_cb(void *closure)
1102 {
1103         struct api_ws_server_req *wreq = closure;
1104         wreq->refcount++;
1105 }
1106
1107 /* decrement the reference count of the request and free/release it on falling to null */
1108 static void api_ws_server_req_unref_cb(void *closure)
1109 {
1110         api_ws_server_req_unref(closure);
1111 }
1112
1113 static void api_ws_server_req_unref(struct api_ws_server_req *wreq)
1114 {
1115         if (wreq == NULL || --wreq->refcount)
1116                 return;
1117
1118         afb_context_disconnect(&wreq->context);
1119         json_object_put(wreq->json);
1120         free(wreq->rcvdata);
1121         api_ws_server_client_unref(wreq->client);
1122         free(wreq);
1123 }
1124
1125 /* get the object of the request */
1126 static struct json_object *api_ws_server_req_json_cb(void *closure)
1127 {
1128         return api_ws_server_req_json(closure);
1129 }
1130
1131 static struct json_object *api_ws_server_req_json(struct api_ws_server_req *wreq)
1132 {
1133         if (wreq->json == NULL) {
1134                 wreq->json = json_tokener_parse(wreq->request);
1135                 if (wreq->json == NULL && strcmp(wreq->request, "null")) {
1136                         /* lazy error detection of json request. Is it to improve? */
1137                         wreq->json = json_object_new_string(wreq->request);
1138                 }
1139         }
1140         return wreq->json;
1141 }
1142
1143 /* get the argument of the request of 'name' */
1144 static struct afb_arg api_ws_server_req_get_cb(void *closure, const char *name)
1145 {
1146         struct api_ws_server_req *wreq = closure;
1147         return afb_msg_json_get_arg(api_ws_server_req_json(wreq), name);
1148 }
1149
1150 static void api_ws_server_req_success_cb(void *closure, struct json_object *obj, const char *info)
1151 {
1152         int rc;
1153         struct writebuf wb = { .count = 0 };
1154         struct api_ws_server_req *wreq = closure;
1155
1156         if (api_ws_write_char(&wb, 'T')
1157          && api_ws_write_uint32(&wb, wreq->msgid)
1158          && api_ws_write_uint32(&wb, (uint32_t)wreq->context.flags)
1159          && api_ws_write_string(&wb, info ? : "")
1160          && api_ws_write_object(&wb, obj)) {
1161                 rc = afb_ws_binary_v(wreq->client->ws, wb.iovec, wb.count);
1162                 if (rc >= 0)
1163                         goto success;
1164         }
1165         ERROR("error while sending success");
1166 success:
1167         json_object_put(obj);
1168 }
1169
1170 static void api_ws_server_req_fail_cb(void *closure, const char *status, const char *info)
1171 {
1172         int rc;
1173         struct writebuf wb = { .count = 0 };
1174         struct api_ws_server_req *wreq = closure;
1175
1176         if (api_ws_write_char(&wb, 'F')
1177          && api_ws_write_uint32(&wb, wreq->msgid)
1178          && api_ws_write_uint32(&wb, (uint32_t)wreq->context.flags)
1179          && api_ws_write_string(&wb, status)
1180          && api_ws_write_string(&wb, info ? : "")) {
1181                 rc = afb_ws_binary_v(wreq->client->ws, wb.iovec, wb.count);
1182                 if (rc >= 0)
1183                         return;
1184         }
1185         ERROR("error while sending fail");
1186 }
1187
1188 static const char *api_ws_server_req_raw_cb(void *closure, size_t *size)
1189 {
1190         struct api_ws_server_req *wreq = closure;
1191         if (size != NULL)
1192                 *size = wreq->lenreq;
1193         return wreq->request;
1194 }
1195
1196 static void api_ws_server_req_send_cb(void *closure, const char *buffer, size_t size)
1197 {
1198         /* TODO: how to put sized buffer as strings? things aren't clear here!!! */
1199         int rc;
1200         struct writebuf wb = { .count = 0 };
1201         struct api_ws_server_req *wreq = closure;
1202
1203         if (api_ws_write_char(&wb, 'X')
1204          && api_ws_write_uint32(&wb, wreq->msgid)
1205          && api_ws_write_uint32(&wb, (uint32_t)wreq->context.flags)
1206          && api_ws_write_string_length(&wb, buffer, size)) {
1207                 rc = afb_ws_binary_v(wreq->client->ws, wb.iovec, wb.count);
1208                 if (rc >= 0)
1209                         return;
1210         }
1211         ERROR("error while sending raw");
1212 }
1213
1214 static int api_ws_server_req_subscribe_cb(void *closure, struct afb_event event)
1215 {
1216         int rc, rc2;
1217         struct writebuf wb = { .count = 0 };
1218         struct api_ws_server_req *wreq = closure;
1219
1220         rc = afb_evt_add_watch(wreq->client->listener, event);
1221         if (rc < 0)
1222                 return rc;
1223
1224         if (api_ws_write_char(&wb, 'S')
1225          && api_ws_write_uint32(&wb, wreq->msgid)
1226          && api_ws_write_uint32(&wb, (uint32_t)afb_evt_event_id(event))
1227          && api_ws_write_string(&wb, afb_evt_event_name(event))) {
1228                 rc2 = afb_ws_binary_v(wreq->client->ws, wb.iovec, wb.count);
1229                 if (rc2 >= 0)
1230                         goto success;
1231         }
1232         ERROR("error while subscribing event");
1233 success:
1234         return rc;
1235 }
1236
1237 static int api_ws_server_req_unsubscribe_cb(void *closure, struct afb_event event)
1238 {
1239         int rc, rc2;
1240         struct writebuf wb = { .count = 0 };
1241         struct api_ws_server_req *wreq = closure;
1242
1243         if (api_ws_write_char(&wb, 'U')
1244          && api_ws_write_uint32(&wb, wreq->msgid)
1245          && api_ws_write_uint32(&wb, (uint32_t)afb_evt_event_id(event))
1246          && api_ws_write_string(&wb, afb_evt_event_name(event))) {
1247                 rc2 = afb_ws_binary_v(wreq->client->ws, wb.iovec, wb.count);
1248                 if (rc2 >= 0)
1249                         goto success;
1250         }
1251         ERROR("error while subscribing event");
1252 success:
1253         rc = afb_evt_remove_watch(wreq->client->listener, event);
1254         return rc;
1255 }
1256
1257 static void api_ws_server_req_subcall_cb(void *closure, const char *api, const char *verb, struct json_object *args, void (*callback)(void*, int, struct json_object*), void *cb_closure)
1258 {
1259         struct api_ws_server_req *wreq = closure;
1260         afb_subcall(&wreq->context, api, verb, args, callback, cb_closure, (struct afb_req){ .itf = &afb_api_ws_req_itf, .closure = wreq });
1261 }
1262
1263 /******************* server part **********************************/
1264
1265 static int api_ws_server_connect(struct api_ws *api);
1266
1267 static int api_ws_server_listen_callback(sd_event_source *src, int fd, uint32_t revents, void *closure)
1268 {
1269         if ((revents & EPOLLIN) != 0)
1270                 api_ws_server_accept(closure);
1271         if ((revents & EPOLLHUP) != 0)
1272                 api_ws_server_connect(closure);
1273         return 0;
1274 }
1275
1276 static void api_ws_server_disconnect(struct api_ws *api)
1277 {
1278         if (api->server.listensrc != NULL) {
1279                 sd_event_source_unref(api->server.listensrc);
1280                 api->server.listensrc = NULL;
1281         }
1282         if (api->fd >= 0) {
1283                 close(api->fd);
1284                 api->fd = -1;
1285         }
1286 }
1287
1288 static int api_ws_server_connect(struct api_ws *api)
1289 {
1290         int rc;
1291
1292         /* ensure disconnected */
1293         api_ws_server_disconnect(api);
1294
1295         /* request the service object name */
1296         api->fd = api_ws_socket(api->path, 1);
1297         if (api->fd < 0)
1298                 ERROR("can't create socket %s", api->path);
1299         else {
1300                 /* listen for service */
1301                 rc = sd_event_add_io(afb_common_get_event_loop(), &api->server.listensrc, api->fd, EPOLLIN, api_ws_server_listen_callback, api);
1302                 if (rc >= 0)
1303                         return 0;
1304                 close(api->fd);
1305                 errno = -rc;
1306                 ERROR("can't add ws object %s", api->path);
1307         }
1308         return -1;
1309 }
1310
1311 /* create the service */
1312 int afb_api_ws_add_server(const char *path)
1313 {
1314         int rc;
1315         struct api_ws *api;
1316
1317         /* creates the ws api object */
1318         api = api_ws_make(path);
1319         if (api == NULL)
1320                 goto error;
1321
1322         /* connect for serving */
1323         rc = api_ws_server_connect(api);
1324         if (rc < 0)
1325                 goto error2;
1326
1327         return 0;
1328
1329 error2:
1330         free(api);
1331 error:
1332         return -1;
1333 }
1334
1335