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_nz(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) && api_ws_write_char(wb, '\0');
 438 }
 439
 440 static int api_ws_write_string_length(struct writebuf *wb, const char *value, size_t length)
 441 {
 442         uint32_t len = (uint32_t)++length;
 443         return (size_t)len == length && len && api_ws_write_uint32(wb, len) && api_ws_write_put(wb, value, length);
 444 }
 445
 446 static int api_ws_write_string(struct writebuf *wb, const char *value)
 447 {
 448         return api_ws_write_string_length(wb, value, strlen(value));
 449 }
 450
 451 static int api_ws_write_object(struct writebuf *wb, struct json_object *object)
 452 {
 453         const char *string = json_object_to_json_string_ext(object, JSON_C_TO_STRING_PLAIN);
 454         return string != NULL && api_ws_write_string(wb, string);
 455 }
 456
 457
 458
 459
 460 /******************* client part **********************************/
 461
 462 /*
 463  * structure for recording query data
 464  */
 465 struct api_ws_memo {
 466         struct api_ws_memo *next;               /* the next memo */
 467         struct api_ws *api;             /* the ws api */
 468         struct afb_req req;             /* the request handle */
 469         struct afb_context *context;    /* the context of the query */
 470         uint32_t msgid;                 /* the message identifier */
 471 };
 472
 473 struct api_ws_event
 474 {
 475         struct api_ws_event *next;
 476         struct afb_event event;
 477         int eventid;
 478         int refcount;
 479 };
 480
 481 /* search a memorized request */
 482 static struct api_ws_memo *api_ws_client_memo_search(struct api_ws *api, uint32_t msgid)
 483 {
 484         struct api_ws_memo *memo;
 485
 486         memo = api->client.memos;
 487         while (memo != NULL && memo->msgid != msgid)
 488                 memo = memo->next;
 489
 490         return memo;
 491 }
 492
 493 /* search the event */
 494 static struct api_ws_event *api_ws_client_event_search(struct api_ws *api, uint32_t eventid, const char *name)
 495 {
 496         struct api_ws_event *ev;
 497
 498         ev = api->client.events;
 499         while (ev != NULL && (ev->eventid != eventid || 0 != strcmp(afb_evt_event_name(ev->event), name)))
 500                 ev = ev->next;
 501
 502         return ev;
 503 }
 504
 505
 506 /* allocates and init the memorizing data */
 507 static struct api_ws_memo *api_ws_client_memo_make(struct api_ws *api, struct afb_req req, struct afb_context *context)
 508 {
 509         struct api_ws_memo *memo;
 510
 511         memo = malloc(sizeof *memo);
 512         if (memo != NULL) {
 513                 afb_req_addref(req);
 514                 memo->req = req;
 515                 memo->context = context;
 516                 do { memo->msgid = ++api->client.id; } while(api_ws_client_memo_search(api, memo->msgid) != NULL);
 517                 memo->api = api;
 518                 memo->next = api->client.memos;
 519                 api->client.memos = memo;
 520         }
 521         return memo;
 522 }
 523
 524 /* free and release the memorizing data */
 525 static void api_ws_client_memo_destroy(struct api_ws_memo *memo)
 526 {
 527         struct api_ws_memo **prv;
 528
 529         prv = &memo->api->client.memos;
 530         while (*prv != NULL) {
 531                 if (*prv == memo) {
 532                         *prv = memo->next;
 533                         break;
 534                 }
 535                 prv = &(*prv)->next;
 536         }
 537
 538         afb_req_unref(memo->req);
 539         free(memo);
 540 }
 541
 542 /* get event data from the message */
 543 static int api_ws_client_msg_event_read(struct readbuf *rb, uint32_t *eventid, const char **name)
 544 {
 545         return api_ws_read_uint32(rb, eventid) && api_ws_read_string(rb, name, NULL);
 546 }
 547
 548 /* get event from the message */
 549 static int api_ws_client_msg_event_get(struct api_ws *api, struct readbuf *rb, struct api_ws_event **ev)
 550 {
 551         const char *name;
 552         uint32_t eventid;
 553
 554         /* get event data from the message */
 555         if (!api_ws_client_msg_event_read(rb, &eventid, &name)) {
 556                 ERROR("Invalid message");
 557                 return 0;
 558         }
 559
 560         /* check conflicts */
 561         *ev = api_ws_client_event_search(api, eventid, name);
 562         if (*ev == NULL) {
 563                 ERROR("event %s not found", name);
 564                 return 0;
 565         }
 566
 567         return 1;
 568 }
 569
 570 /* get event from the message */
 571 static int api_ws_client_msg_memo_get(struct api_ws *api, struct readbuf *rb, struct api_ws_memo **memo)
 572 {
 573         uint32_t msgid;
 574
 575         /* get event data from the message */
 576         if (!api_ws_read_uint32(rb, &msgid)) {
 577                 ERROR("Invalid message");
 578                 return 0;
 579         }
 580
 581         /* get the memo */
 582         *memo = api_ws_client_memo_search(api, msgid);
 583         if (*memo == NULL) {
 584                 ERROR("message not found");
 585                 return 0;
 586         }
 587
 588         return 1;
 589 }
 590
 591 /* read a subscrition message */
 592 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)
 593 {
 594         return api_ws_client_msg_memo_get(api, rb, memo) && api_ws_client_msg_event_get(api, rb, ev);
 595 }
 596
 597 /* adds an event */
 598 static void api_ws_client_event_create(struct api_ws *api, struct readbuf *rb)
 599 {
 600         size_t offset;
 601         const char *name;
 602         uint32_t eventid;
 603         struct api_ws_event *ev;
 604
 605         /* get event data from the message */
 606         offset = api_ws_client_msg_event_read(rb, &eventid, &name);
 607         if (offset == 0) {
 608                 ERROR("Invalid message");
 609                 return;
 610         }
 611
 612         /* check conflicts */
 613         ev = api_ws_client_event_search(api, eventid, name);
 614         if (ev != NULL) {
 615                 ev->refcount++;
 616                 return;
 617         }
 618
 619         /* no conflict, try to add it */
 620         ev = malloc(sizeof *ev);
 621         if (ev != NULL) {
 622                 ev->event = afb_evt_create_event(name);
 623                 if (ev->event.closure == NULL)
 624                         free(ev);
 625                 else {
 626                         ev->refcount = 1;
 627                         ev->eventid = eventid;
 628                         ev->next = api->client.events;
 629                         api->client.events = ev;
 630                         return;
 631                 }
 632         }
 633         ERROR("can't create event %s, out of memory", name);
 634 }
 635
 636 /* removes an event */
 637 static void api_ws_client_event_drop(struct api_ws *api, struct readbuf *rb)
 638 {
 639         struct api_ws_event *ev, **prv;
 640
 641         /* retrieves the event */
 642         if (!api_ws_client_msg_event_get(api, rb, &ev))
 643                 return;
 644
 645         /* decrease the reference count */
 646         if (--ev->refcount)
 647                 return;
 648
 649         /* unlinks the event */
 650         prv = &api->client.events;
 651         while (*prv != ev)
 652                 prv = &(*prv)->next;
 653         *prv = ev->next;
 654
 655         /* destroys the event */
 656         afb_event_drop(ev->event);
 657         free(ev);
 658 }
 659
 660 /* subscribes an event */
 661 static void api_ws_client_event_subscribe(struct api_ws *api, struct readbuf *rb)
 662 {
 663         struct api_ws_event *ev;
 664         struct api_ws_memo *memo;
 665
 666         if (api_ws_client_msg_subscription_get(api, rb, &ev, &memo)) {
 667                 /* subscribe the request from the event */
 668                 if (afb_req_subscribe(memo->req, ev->event) < 0)
 669                         ERROR("can't subscribe: %m");
 670         }
 671 }
 672
 673 /* unsubscribes an event */
 674 static void api_ws_client_event_unsubscribe(struct api_ws *api, struct readbuf *rb)
 675 {
 676         struct api_ws_event *ev;
 677         struct api_ws_memo *memo;
 678
 679         if (api_ws_client_msg_subscription_get(api, rb, &ev, &memo)) {
 680                 /* unsubscribe the request from the event */
 681                 if (afb_req_unsubscribe(memo->req, ev->event) < 0)
 682                         ERROR("can't unsubscribe: %m");
 683         }
 684 }
 685
 686 /* receives broadcasted events */
 687 static void api_ws_client_event_broadcast(struct api_ws *api, struct readbuf *rb)
 688 {
 689         struct json_object *object;
 690         const char *event;
 691
 692         if (api_ws_read_string(rb, &event, NULL) && api_ws_read_object(rb, &object))
 693                 afb_evt_broadcast(event, object);
 694         else
 695                 ERROR("unreadable broadcasted event");
 696 }
 697
 698 /* pushs an event */
 699 static void api_ws_client_event_push(struct api_ws *api, struct readbuf *rb)
 700 {
 701         struct api_ws_event *ev;
 702         struct json_object *object;
 703
 704         if (api_ws_client_msg_event_get(api, rb, &ev) && api_ws_read_object(rb, &object))
 705                 afb_event_push(ev->event, object);
 706         else
 707                 ERROR("unreadable push event");
 708 }
 709
 710 static void api_ws_client_reply_success(struct api_ws *api, struct readbuf *rb)
 711 {
 712         struct api_ws_memo *memo;
 713         struct json_object *object;
 714         const char *info;
 715         uint32_t flags;
 716
 717         /* retrieve the message data */
 718         if (!api_ws_client_msg_memo_get(api, rb, &memo))
 719                 return;
 720
 721         if (api_ws_read_uint32(rb, &flags)
 722          && api_ws_read_string(rb, &info, NULL)
 723          && api_ws_read_object(rb, &object)) {
 724                 memo->context->flags = (unsigned)flags;
 725                 afb_req_success(memo->req, object, *info ? info : NULL);
 726         } else {
 727                 /* failing to have the answer */
 728                 afb_req_fail(memo->req, "error", "ws error");
 729         }
 730         api_ws_client_memo_destroy(memo);
 731 }
 732
 733 static void api_ws_client_reply_fail(struct api_ws *api, struct readbuf *rb)
 734 {
 735         struct api_ws_memo *memo;
 736         const char *info, *status;
 737         uint32_t flags;
 738
 739         /* retrieve the message data */
 740         if (!api_ws_client_msg_memo_get(api, rb, &memo))
 741                 return;
 742
 743         if (api_ws_read_uint32(rb, &flags)
 744          && api_ws_read_string(rb, &status, NULL)
 745          && api_ws_read_string(rb, &info, NULL)) {
 746                 memo->context->flags = (unsigned)flags;
 747                 afb_req_fail(memo->req, status, *info ? info : NULL);
 748         } else {
 749                 /* failing to have the answer */
 750                 afb_req_fail(memo->req, "error", "ws error");
 751         }
 752         api_ws_client_memo_destroy(memo);
 753 }
 754
 755 static void api_ws_client_reply_send(struct api_ws *api, struct readbuf *rb)
 756 {
 757         struct api_ws_memo *memo;
 758         const char *data;
 759         size_t length;
 760         uint32_t flags;
 761
 762         /* retrieve the message data */
 763         if (!api_ws_client_msg_memo_get(api, rb, &memo))
 764                 return;
 765
 766         if (api_ws_read_uint32(rb, &flags)
 767          && api_ws_read_string(rb, &data, &length)) {
 768                 memo->context->flags = (unsigned)flags;
 769                 afb_req_send(memo->req, data, length);
 770         } else {
 771                 /* failing to have the answer */
 772                 afb_req_fail(memo->req, "error", "ws error");
 773         }
 774         api_ws_client_memo_destroy(memo);
 775 }
 776
 777 /* callback when receiving binary data */
 778 static void api_ws_client_on_binary(void *closure, char *data, size_t size)
 779 {
 780         if (size > 0) {
 781                 struct readbuf rb = { .head = data, .end = data + size };
 782                 switch (*rb.head++) {
 783                 case 'T': /* success */
 784                         api_ws_client_reply_success(closure, &rb);
 785                         break;
 786                 case 'F': /* fail */
 787                         api_ws_client_reply_fail(closure, &rb);
 788                         break;
 789                 case 'X': /* send */
 790                         api_ws_client_reply_send(closure, &rb);
 791                         break;
 792                 case '*': /* broadcast */
 793                         api_ws_client_event_broadcast(closure, &rb);
 794                         break;
 795                 case '+': /* creates the event */
 796                         api_ws_client_event_create(closure, &rb);
 797                         break;
 798                 case '-': /* drops the event */
 799                         api_ws_client_event_drop(closure, &rb);
 800                         break;
 801                 case '!': /* pushs the event */
 802                         api_ws_client_event_push(closure, &rb);
 803                         break;
 804                 case 'S': /* subscribe event for a request */
 805                         api_ws_client_event_subscribe(closure, &rb);
 806                         break;
 807                 case 'U': /* unsubscribe event for a request */
 808                         api_ws_client_event_unsubscribe(closure, &rb);
 809                         break;
 810                 default: /* unexpected message */
 811                         break;
 812                 }
 813         }
 814         free(data);
 815 }
 816
 817 /* on call, propagate it to the ws service */
 818 static void api_ws_client_call_cb(void * closure, struct afb_req req, struct afb_context *context, const char *verb, size_t lenverb)
 819 {
 820         int rc;
 821         struct api_ws_memo *memo;
 822         struct writebuf wb = { .count = 0 };
 823         const char *raw;
 824         size_t szraw;
 825         struct api_ws *api = closure;
 826
 827         /* create the recording data */
 828         memo = api_ws_client_memo_make(api, req, context);
 829         if (memo == NULL) {
 830                 afb_req_fail(req, "error", "out of memory");
 831                 return;
 832         }
 833
 834         /* creates the call message */
 835         raw = afb_req_raw(req, &szraw);
 836         if (raw == NULL)
 837                 goto internal_error;
 838         if (!api_ws_write_uint32(&wb, memo->msgid)
 839          || !api_ws_write_uint32(&wb, (uint32_t)context->flags)
 840          || !api_ws_write_string_nz(&wb, verb, lenverb)
 841          || !api_ws_write_string(&wb, afb_session_uuid(context->session))
 842          || !api_ws_write_string_length(&wb, raw, szraw))
 843                 goto overflow;
 844
 845         /* send */
 846         rc = afb_ws_binary_v(api->client.ws, wb.iovec, wb.count);
 847         if (rc < 0)
 848                 goto ws_send_error;
 849         return;
 850
 851 ws_send_error:
 852         afb_req_fail(req, "error", "websocket sending error");
 853         goto clean_memo;
 854
 855 internal_error:
 856         afb_req_fail(req, "error", "internal: raw is NULL!");
 857         goto clean_memo;
 858
 859 overflow:
 860         afb_req_fail(req, "error", "overflow: size doesn't match 32 bits!");
 861
 862 clean_memo:
 863         api_ws_client_memo_destroy(memo);
 864 }
 865
 866 static int api_ws_service_start_cb(void *closure, int share_session, int onneed)
 867 {
 868         struct api_ws *api = closure;
 869
 870         /* not an error when onneed */
 871         if (onneed != 0)
 872                 return 0;
 873
 874         /* already started: it is an error */
 875         ERROR("The WS binding %s is not a startable service", api->path);
 876         return -1;
 877 }
 878
 879 /*  */
 880 static void api_ws_client_disconnect(struct api_ws *api)
 881 {
 882         if (api->fd >= 0) {
 883                 afb_ws_destroy(api->client.ws);
 884                 api->client.ws = NULL;
 885                 close(api->fd);
 886                 api->fd = -1;
 887         }
 888 }
 889
 890 /*  */
 891 static int api_ws_client_connect(struct api_ws *api)
 892 {
 893         struct afb_ws *ws;
 894         int fd;
 895
 896         fd = api_ws_socket(api->path, 0);
 897         if (fd >= 0) {
 898                 ws = afb_ws_create(afb_common_get_event_loop(), fd, &api_ws_client_ws_itf, api);
 899                 if (ws != NULL) {
 900                         api->client.ws = ws;
 901                         api->fd = fd;
 902                         return 0;
 903                 }
 904                 close(fd);
 905         }
 906         return -1;
 907 }
 908
 909 /* adds a afb-ws-service client api */
 910 int afb_api_ws_add_client(const char *path)
 911 {
 912         int rc;
 913         struct api_ws *api;
 914         struct afb_api afb_api;
 915
 916         /* create the ws client api */
 917         api = api_ws_make(path);
 918         if (api == NULL)
 919                 goto error;
 920
 921         /* connect to the service */
 922         rc = api_ws_client_connect(api);
 923         if (rc < 0) {
 924                 ERROR("can't connect to ws service %s", api->path);
 925                 goto error2;
 926         }
 927
 928         /* record it as an API */
 929         afb_api.closure = api;
 930         afb_api.call = api_ws_client_call_cb;
 931         afb_api.service_start = api_ws_service_start_cb;
 932         if (afb_apis_add(api->api, afb_api) < 0)
 933                 goto error3;
 934
 935         return 0;
 936
 937 error3:
 938         api_ws_client_disconnect(api);
 939 error2:
 940         free(api);
 941 error:
 942         return -1;
 943 }
 944
 945 /******************* client description part for server *****************************/
 946
 947 static void api_ws_server_client_unref(struct api_ws_client *client)
 948 {
 949         if (!--client->refcount) {
 950                 afb_evt_listener_unref(client->listener);
 951                 afb_ws_destroy(client->ws);
 952                 free(client);
 953         }
 954 }
 955
 956 /* on call, propagate it to the ws service */
 957 static void api_ws_server_called(struct api_ws_client *client, struct readbuf *rb, char *data, size_t size)
 958 {
 959         struct api_ws_server_req *wreq;
 960         struct afb_req areq;
 961         const char *uuid, *verb;
 962         uint32_t flags;
 963
 964         client->refcount++;
 965
 966         /* create the request */
 967         wreq = calloc(1 , sizeof *wreq);
 968         if (wreq == NULL)
 969                 goto out_of_memory;
 970
 971         wreq->client = client;
 972         wreq->rcvdata = data;
 973         wreq->refcount = 1;
 974
 975         /* reads the call message data */
 976         if (!api_ws_read_uint32(rb, &wreq->msgid)
 977          || !api_ws_read_uint32(rb, &flags)
 978          || !api_ws_read_string(rb, &verb, NULL)
 979          || !api_ws_read_string(rb, &uuid, NULL)
 980          || !api_ws_read_string(rb, &wreq->request, &wreq->lenreq))
 981                 goto overflow;
 982
 983         /* init the context */
 984         if (afb_context_connect(&wreq->context, uuid, NULL) < 0)
 985                 goto out_of_memory;
 986         wreq->context.flags = flags;
 987
 988         /* makes the call */
 989         areq.itf = &afb_api_ws_req_itf;
 990         areq.closure = wreq;
 991         afb_apis_call_(areq, &wreq->context, client->api, verb);
 992         api_ws_server_req_unref(wreq);
 993         return;
 994
 995 out_of_memory:
 996 overflow:
 997         free(wreq);
 998         free(data);
 999         api_ws_server_client_unref(client);
1000 }
1001
1002 /* callback when receiving binary data */
1003 static void api_ws_server_on_binary(void *closure, char *data, size_t size)
1004 {
1005         struct readbuf rb = { .head = data, .end = data + size };
1006         api_ws_server_called(closure, &rb, data, size);
1007 }
1008
1009 /* callback when receiving a hangup */
1010 static void api_ws_server_on_hangup(void *closure)
1011 {
1012         struct api_ws_client *client = closure;
1013
1014         /* close the socket */
1015         if (client->fd >= 0) {
1016                 close(client->fd);
1017                 client->fd = -1;
1018         }
1019
1020         /* release the client */
1021         api_ws_server_client_unref(client);
1022 }
1023
1024 static void api_ws_server_accept(struct api_ws *api)
1025 {
1026         struct api_ws_client *client;
1027         struct sockaddr addr;
1028         socklen_t lenaddr;
1029
1030         client = calloc(1, sizeof *client);
1031         if (client != NULL) {
1032                 client->listener = afb_evt_listener_create(&api_ws_server_evt_itf, client);
1033                 if (client->listener != NULL) {
1034                         lenaddr = (socklen_t)sizeof addr;
1035                         client->fd = accept(api->fd, &addr, &lenaddr);
1036                         if (client->fd >= 0) {
1037                                 fcntl(client->fd, F_SETFD, FD_CLOEXEC);
1038                                 fcntl(client->fd, F_SETFL, O_NONBLOCK);
1039                                 client->ws = afb_ws_create(afb_common_get_event_loop(), client->fd, &api_ws_server_ws_itf, client);
1040                                 if (client->ws != NULL) {
1041                                         client->api = api->api;
1042                                         client->refcount = 1;
1043                                         return;
1044                                 }
1045                                 close(client->fd);
1046                         }
1047                         afb_evt_listener_unref(client->listener);
1048                 }
1049                 free(client);
1050         }
1051 }
1052
1053 /******************* server part: manage events **********************************/
1054
1055 static void api_ws_server_event_send(struct api_ws_client *client, char order, const char *event, int eventid, const char *data)
1056 {
1057         int rc;
1058         struct writebuf wb = { .count = 0 };
1059
1060         if (api_ws_write_char(&wb, order)
1061          && api_ws_write_uint32(&wb, eventid)
1062          && api_ws_write_string(&wb, event)
1063          && (data == NULL || api_ws_write_string(&wb, data))) {
1064                 rc = afb_ws_binary_v(client->ws, wb.iovec, wb.count);
1065                 if (rc >= 0)
1066                         return;
1067         }
1068         ERROR("error while sending %c for event %s", order, event);
1069 }
1070
1071 static void api_ws_server_event_add(void *closure, const char *event, int eventid)
1072 {
1073         api_ws_server_event_send(closure, '+', event, eventid, NULL);
1074 }
1075
1076 static void api_ws_server_event_remove(void *closure, const char *event, int eventid)
1077 {
1078         api_ws_server_event_send(closure, '-', event, eventid, NULL);
1079 }
1080
1081 static void api_ws_server_event_push(void *closure, const char *event, int eventid, struct json_object *object)
1082 {
1083         const char *data = json_object_to_json_string_ext(object, JSON_C_TO_STRING_PLAIN);
1084         api_ws_server_event_send(closure, '!', event, eventid, data ? : "null");
1085         json_object_put(object);
1086 }
1087
1088 static void api_ws_server_event_broadcast(void *closure, const char *event, int eventid, struct json_object *object)
1089 {
1090         int rc;
1091         struct api_ws_client *client = closure;
1092
1093         struct writebuf wb = { .count = 0 };
1094
1095         if (api_ws_write_char(&wb, '*') && api_ws_write_string(&wb, event) && api_ws_write_object(&wb, object)) {
1096                 rc = afb_ws_binary_v(client->ws, wb.iovec, wb.count);
1097                 if (rc < 0)
1098                         ERROR("error while broadcasting event %s", event);
1099         } else
1100                 ERROR("error while broadcasting event %s", event);
1101         json_object_put(object);
1102 }
1103
1104 /******************* ws request part for server *****************/
1105
1106 /* increment the reference count of the request */
1107 static void api_ws_server_req_addref_cb(void *closure)
1108 {
1109         struct api_ws_server_req *wreq = closure;
1110         wreq->refcount++;
1111 }
1112
1113 /* decrement the reference count of the request and free/release it on falling to null */
1114 static void api_ws_server_req_unref_cb(void *closure)
1115 {
1116         api_ws_server_req_unref(closure);
1117 }
1118
1119 static void api_ws_server_req_unref(struct api_ws_server_req *wreq)
1120 {
1121         if (wreq == NULL || --wreq->refcount)
1122                 return;
1123
1124         afb_context_disconnect(&wreq->context);
1125         json_object_put(wreq->json);
1126         free(wreq->rcvdata);
1127         api_ws_server_client_unref(wreq->client);
1128         free(wreq);
1129 }
1130
1131 /* get the object of the request */
1132 static struct json_object *api_ws_server_req_json_cb(void *closure)
1133 {
1134         return api_ws_server_req_json(closure);
1135 }
1136
1137 static struct json_object *api_ws_server_req_json(struct api_ws_server_req *wreq)
1138 {
1139         if (wreq->json == NULL) {
1140                 wreq->json = json_tokener_parse(wreq->request);
1141                 if (wreq->json == NULL && strcmp(wreq->request, "null")) {
1142                         /* lazy error detection of json request. Is it to improve? */
1143                         wreq->json = json_object_new_string(wreq->request);
1144                 }
1145         }
1146         return wreq->json;
1147 }
1148
1149 /* get the argument of the request of 'name' */
1150 static struct afb_arg api_ws_server_req_get_cb(void *closure, const char *name)
1151 {
1152         struct api_ws_server_req *wreq = closure;
1153         return afb_msg_json_get_arg(api_ws_server_req_json(wreq), name);
1154 }
1155
1156 static void api_ws_server_req_success_cb(void *closure, struct json_object *obj, const char *info)
1157 {
1158         int rc;
1159         struct writebuf wb = { .count = 0 };
1160         struct api_ws_server_req *wreq = closure;
1161
1162         if (api_ws_write_char(&wb, 'T')
1163          && api_ws_write_uint32(&wb, wreq->msgid)
1164          && api_ws_write_uint32(&wb, (uint32_t)wreq->context.flags)
1165          && api_ws_write_string(&wb, info ? : "")
1166          && api_ws_write_object(&wb, obj)) {
1167                 rc = afb_ws_binary_v(wreq->client->ws, wb.iovec, wb.count);
1168                 if (rc >= 0)
1169                         goto success;
1170         }
1171         ERROR("error while sending success");
1172 success:
1173         json_object_put(obj);
1174 }
1175
1176 static void api_ws_server_req_fail_cb(void *closure, const char *status, const char *info)
1177 {
1178         int rc;
1179         struct writebuf wb = { .count = 0 };
1180         struct api_ws_server_req *wreq = closure;
1181
1182         if (api_ws_write_char(&wb, 'F')
1183          && api_ws_write_uint32(&wb, wreq->msgid)
1184          && api_ws_write_uint32(&wb, (uint32_t)wreq->context.flags)
1185          && api_ws_write_string(&wb, status)
1186          && api_ws_write_string(&wb, info ? : "")) {
1187                 rc = afb_ws_binary_v(wreq->client->ws, wb.iovec, wb.count);
1188                 if (rc >= 0)
1189                         return;
1190         }
1191         ERROR("error while sending fail");
1192 }
1193
1194 static const char *api_ws_server_req_raw_cb(void *closure, size_t *size)
1195 {
1196         struct api_ws_server_req *wreq = closure;
1197         if (size != NULL)
1198                 *size = wreq->lenreq;
1199         return wreq->request;
1200 }
1201
1202 static void api_ws_server_req_send_cb(void *closure, const char *buffer, size_t size)
1203 {
1204         /* TODO: how to put sized buffer as strings? things aren't clear here!!! */
1205         int rc;
1206         struct writebuf wb = { .count = 0 };
1207         struct api_ws_server_req *wreq = closure;
1208
1209         if (api_ws_write_char(&wb, 'X')
1210          && api_ws_write_uint32(&wb, wreq->msgid)
1211          && api_ws_write_uint32(&wb, (uint32_t)wreq->context.flags)
1212          && api_ws_write_string_length(&wb, buffer, size)) {
1213                 rc = afb_ws_binary_v(wreq->client->ws, wb.iovec, wb.count);
1214                 if (rc >= 0)
1215                         return;
1216         }
1217         ERROR("error while sending raw");
1218 }
1219
1220 static int api_ws_server_req_subscribe_cb(void *closure, struct afb_event event)
1221 {
1222         int rc, rc2;
1223         struct writebuf wb = { .count = 0 };
1224         struct api_ws_server_req *wreq = closure;
1225
1226         rc = afb_evt_add_watch(wreq->client->listener, event);
1227         if (rc < 0)
1228                 return rc;
1229
1230         if (api_ws_write_char(&wb, 'S')
1231          && api_ws_write_uint32(&wb, wreq->msgid)
1232          && api_ws_write_uint32(&wb, (uint32_t)afb_evt_event_id(event))
1233          && api_ws_write_string(&wb, afb_evt_event_name(event))) {
1234                 rc2 = afb_ws_binary_v(wreq->client->ws, wb.iovec, wb.count);
1235                 if (rc2 >= 0)
1236                         goto success;
1237         }
1238         ERROR("error while subscribing event");
1239 success:
1240         return rc;
1241 }
1242
1243 static int api_ws_server_req_unsubscribe_cb(void *closure, struct afb_event event)
1244 {
1245         int rc, rc2;
1246         struct writebuf wb = { .count = 0 };
1247         struct api_ws_server_req *wreq = closure;
1248
1249         if (api_ws_write_char(&wb, 'U')
1250          && api_ws_write_uint32(&wb, wreq->msgid)
1251          && api_ws_write_uint32(&wb, (uint32_t)afb_evt_event_id(event))
1252          && api_ws_write_string(&wb, afb_evt_event_name(event))) {
1253                 rc2 = afb_ws_binary_v(wreq->client->ws, wb.iovec, wb.count);
1254                 if (rc2 >= 0)
1255                         goto success;
1256         }
1257         ERROR("error while subscribing event");
1258 success:
1259         rc = afb_evt_remove_watch(wreq->client->listener, event);
1260         return rc;
1261 }
1262
1263 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)
1264 {
1265         struct api_ws_server_req *wreq = closure;
1266         afb_subcall(&wreq->context, api, verb, args, callback, cb_closure, (struct afb_req){ .itf = &afb_api_ws_req_itf, .closure = wreq });
1267 }
1268
1269 /******************* server part **********************************/
1270
1271 static int api_ws_server_connect(struct api_ws *api);
1272
1273 static int api_ws_server_listen_callback(sd_event_source *src, int fd, uint32_t revents, void *closure)
1274 {
1275         if ((revents & EPOLLIN) != 0)
1276                 api_ws_server_accept(closure);
1277         if ((revents & EPOLLHUP) != 0)
1278                 api_ws_server_connect(closure);
1279         return 0;
1280 }
1281
1282 static void api_ws_server_disconnect(struct api_ws *api)
1283 {
1284         if (api->server.listensrc != NULL) {
1285                 sd_event_source_unref(api->server.listensrc);
1286                 api->server.listensrc = NULL;
1287         }
1288         if (api->fd >= 0) {
1289                 close(api->fd);
1290                 api->fd = -1;
1291         }
1292 }
1293
1294 static int api_ws_server_connect(struct api_ws *api)
1295 {
1296         int rc;
1297
1298         /* ensure disconnected */
1299         api_ws_server_disconnect(api);
1300
1301         /* request the service object name */
1302         api->fd = api_ws_socket(api->path, 1);
1303         if (api->fd < 0)
1304                 ERROR("can't create socket %s", api->path);
1305         else {
1306                 /* listen for service */
1307                 rc = sd_event_add_io(afb_common_get_event_loop(), &api->server.listensrc, api->fd, EPOLLIN, api_ws_server_listen_callback, api);
1308                 if (rc >= 0)
1309                         return 0;
1310                 close(api->fd);
1311                 errno = -rc;
1312                 ERROR("can't add ws object %s", api->path);
1313         }
1314         return -1;
1315 }
1316
1317 /* create the service */
1318 int afb_api_ws_add_server(const char *path)
1319 {
1320         int rc;
1321         struct api_ws *api;
1322
1323         /* creates the ws api object */
1324         api = api_ws_make(path);
1325         if (api == NULL)
1326                 goto error;
1327
1328         /* connect for serving */
1329         rc = api_ws_server_connect(api);
1330         if (rc < 0)
1331                 goto error2;
1332
1333         return 0;
1334
1335 error2:
1336         free(api);
1337 error:
1338         return -1;
1339 }
1340
1341