src/afb-proto-ws.c

   1 /*
   2  * Copyright (C) 2015-2019 "IoT.bzh"
   3  * Author José Bollo <jose.bollo@iot.bzh>
   4  *
   5  * Licensed under the Apache License, Version 2.0 (the "License");
   6  * you may not use this file except in compliance with the License.
   7  * You may obtain a copy of the License at
   8  *
   9  *   http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  * Unless required by applicable law or agreed to in writing, software
  12  * distributed under the License is distributed on an "AS IS" BASIS,
  13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14  * See the License for the specific language governing permissions and
  15  * limitations under the License.
  16  */
  17
  18 #define _GNU_SOURCE
  19
  20 #include <stdlib.h>
  21 #include <string.h>
  22 #include <assert.h>
  23 #include <fcntl.h>
  24 #include <unistd.h>
  25 #include <errno.h>
  26 #include <endian.h>
  27 #include <netdb.h>
  28 #include <sys/types.h>
  29 #include <sys/socket.h>
  30 #include <sys/un.h>
  31 #include <pthread.h>
  32
  33 #include <json-c/json.h>
  34
  35 #include "afb-ws.h"
  36 #include "afb-msg-json.h"
  37 #include "afb-proto-ws.h"
  38 #include "fdev.h"
  39 #include "verbose.h"
  40
  41 struct afb_proto_ws;
  42
  43 /******** implementation of internal binder protocol per api **************/
  44 /*
  45
  46 This protocol is asymetric: there is a client and a server
  47
  48 The client can require the following actions:
  49
  50   - call a verb
  51
  52   - ask for description
  53
  54 The server must reply to the previous actions by
  55
  56   - answering success or failure of the call
  57
  58   - answering the required description
  59
  60 The server can also within the context of a call
  61
  62   - subscribe or unsubscribe an event
  63
  64 For the purpose of handling events the server can:
  65
  66   - create/destroy an event
  67
  68   - push or brodcast data as an event
  69
  70 */
  71 /************** constants for protocol definition *************************/
  72
  73 #define CHAR_FOR_CALL             'C'
  74 #define CHAR_FOR_REPLY            'Y'
  75 #define CHAR_FOR_EVT_BROADCAST    '*'
  76 #define CHAR_FOR_EVT_ADD          '+'
  77 #define CHAR_FOR_EVT_DEL          '-'
  78 #define CHAR_FOR_EVT_PUSH         '!'
  79 #define CHAR_FOR_EVT_SUBSCRIBE    'S'
  80 #define CHAR_FOR_EVT_UNSUBSCRIBE  'U'
  81 #define CHAR_FOR_DESCRIBE         'D'
  82 #define CHAR_FOR_DESCRIPTION      'd'
  83
  84 /******************* handling calls *****************************/
  85
  86 /*
  87  * structure for recording calls on client side
  88  */
  89 struct client_call {
  90         struct client_call *next;       /* the next call */
  91         struct afb_proto_ws *protows;   /* the proto_ws */
  92         void *request;                  /* the request closure */
  93         uint32_t callid;                /* the message identifier */
  94 };
  95
  96 /*
  97  * structure for a ws request
  98  */
  99 struct afb_proto_ws_call {
 100         struct client_call *next;       /* the next call */
 101         struct afb_proto_ws *protows;   /* the client of the request */
 102         uint32_t refcount;              /* reference count */
 103         uint32_t callid;                /* the incoming request callid */
 104         char *buffer;                   /* the incoming buffer */
 105 };
 106
 107 /*
 108  * structure for recording describe requests
 109  */
 110 struct client_describe
 111 {
 112         struct client_describe *next;
 113         struct afb_proto_ws *protows;
 114         void (*callback)(void*, struct json_object*);
 115         void *closure;
 116         uint32_t descid;
 117 };
 118
 119 /*
 120  * structure for jobs of describing
 121  */
 122 struct afb_proto_ws_describe
 123 {
 124         struct afb_proto_ws *protows;
 125         uint32_t descid;
 126 };
 127
 128 /******************* proto description for client or servers ******************/
 129
 130 struct afb_proto_ws
 131 {
 132         /* count of references */
 133         int refcount;
 134
 135         /* resource control */
 136         pthread_mutex_t mutex;
 137
 138         /* websocket */
 139         struct afb_ws *ws;
 140
 141         /* the client closure */
 142         void *closure;
 143
 144         /* the client side interface */
 145         const struct afb_proto_ws_client_itf *client_itf;
 146
 147         /* the server side interface */
 148         const struct afb_proto_ws_server_itf *server_itf;
 149
 150         /* emitted calls (client side) */
 151         struct client_call *calls;
 152
 153         /* pending description (client side) */
 154         struct client_describe *describes;
 155
 156         /* on hangup callback */
 157         void (*on_hangup)(void *closure);
 158
 159         /* queuing facility for processing messages */
 160         int (*queuing)(struct afb_proto_ws *proto, void (*process)(int s, void *c), void *closure);
 161 };
 162
 163 /******************* streaming objects **********************************/
 164
 165 #define WRITEBUF_COUNT_MAX      32
 166 #define WRITEBUF_BUFSZ          (WRITEBUF_COUNT_MAX * sizeof(uint32_t))
 167
 168 struct writebuf
 169 {
 170         int iovcount, bufcount;
 171         struct iovec iovec[WRITEBUF_COUNT_MAX];
 172         char buf[WRITEBUF_BUFSZ];
 173 };
 174
 175 struct readbuf
 176 {
 177         char *base, *head, *end;
 178 };
 179
 180 struct binary
 181 {
 182         struct afb_proto_ws *protows;
 183         struct readbuf rb;
 184 };
 185
 186 /******************* common useful tools **********************************/
 187
 188 /**
 189  * translate a pointer to some integer
 190  * @param ptr the pointer to translate
 191  * @return an integer
 192  */
 193 static inline uint32_t ptr2id(void *ptr)
 194 {
 195         return (uint32_t)(((intptr_t)ptr) >> 6);
 196 }
 197
 198 /******************* serialisation part **********************************/
 199
 200 static char *readbuf_get(struct readbuf *rb, uint32_t length)
 201 {
 202         char *before = rb->head;
 203         char *after = before + length;
 204         if (after > rb->end)
 205                 return 0;
 206         rb->head = after;
 207         return before;
 208 }
 209
 210 __attribute__((unused))
 211 static int readbuf_char(struct readbuf *rb, char *value)
 212 {
 213         if (rb->head >= rb->end)
 214                 return 0;
 215         *value = *rb->head++;
 216         return 1;
 217 }
 218
 219 static int readbuf_uint32(struct readbuf *rb, uint32_t *value)
 220 {
 221         char *after = rb->head + sizeof *value;
 222         if (after > rb->end)
 223                 return 0;
 224         memcpy(value, rb->head, sizeof *value);
 225         rb->head = after;
 226         *value = le32toh(*value);
 227         return 1;
 228 }
 229
 230 static int _readbuf_string_(struct readbuf *rb, const char **value, size_t *length, int nulok)
 231 {
 232         uint32_t len;
 233         if (!readbuf_uint32(rb, &len))
 234                 return 0;
 235         if (!len) {
 236                 if (!nulok)
 237                         return 0;
 238                 *value = NULL;
 239                 if (length)
 240                         *length = 0;
 241                 return 1;
 242         }
 243         if (length)
 244                 *length = (size_t)(len - 1);
 245         return (*value = readbuf_get(rb, len)) != NULL &&  rb->head[-1] == 0;
 246 }
 247
 248
 249 static int readbuf_string(struct readbuf *rb, const char **value, size_t *length)
 250 {
 251         return _readbuf_string_(rb, value, length, 0);
 252 }
 253
 254 static int readbuf_nullstring(struct readbuf *rb, const char **value, size_t *length)
 255 {
 256         return _readbuf_string_(rb, value, length, 1);
 257 }
 258
 259 static int readbuf_object(struct readbuf *rb, struct json_object **object)
 260 {
 261         const char *string;
 262         struct json_object *o;
 263         enum json_tokener_error jerr;
 264         int rc = readbuf_string(rb, &string, NULL);
 265         if (rc) {
 266                 o = json_tokener_parse_verbose(string, &jerr);
 267                 if (jerr != json_tokener_success)
 268                         o = json_object_new_string(string);
 269                 *object = o;
 270         }
 271         return rc;
 272 }
 273
 274 static int writebuf_put(struct writebuf *wb, const void *value, size_t length)
 275 {
 276         int i = wb->iovcount;
 277         if (i == WRITEBUF_COUNT_MAX)
 278                 return 0;
 279         wb->iovec[i].iov_base = (void*)value;
 280         wb->iovec[i].iov_len = length;
 281         wb->iovcount = i + 1;
 282         return 1;
 283 }
 284
 285 static int writebuf_putbuf(struct writebuf *wb, const void *value, int length)
 286 {
 287         char *p;
 288         int i = wb->iovcount, n = wb->bufcount, nafter;
 289
 290         /* check enough length */
 291         nafter = n + length;
 292         if (nafter > WRITEBUF_BUFSZ)
 293                 return 0;
 294
 295         /* get where to store */
 296         p = &wb->buf[n];
 297         if (i && p == (((char*)wb->iovec[i - 1].iov_base) + wb->iovec[i - 1].iov_len))
 298                 /* increase previous iovec */
 299                 wb->iovec[i - 1].iov_len += (size_t)length;
 300         else if (i == WRITEBUF_COUNT_MAX)
 301                 /* no more iovec */
 302                 return 0;
 303         else {
 304                 /* new iovec */
 305                 wb->iovec[i].iov_base = p;
 306                 wb->iovec[i].iov_len = (size_t)length;
 307                 wb->iovcount = i + 1;
 308         }
 309         /* store now */
 310         memcpy(p, value, (size_t)length);
 311         wb->bufcount = nafter;
 312         return 1;
 313 }
 314
 315 static int writebuf_char(struct writebuf *wb, char value)
 316 {
 317         return writebuf_putbuf(wb, &value, 1);
 318 }
 319
 320 static int writebuf_uint32(struct writebuf *wb, uint32_t value)
 321 {
 322         value = htole32(value);
 323         return writebuf_putbuf(wb, &value, (int)sizeof value);
 324 }
 325
 326 static int writebuf_string_length(struct writebuf *wb, const char *value, size_t length)
 327 {
 328         uint32_t len = (uint32_t)++length;
 329         return (size_t)len == length && len && writebuf_uint32(wb, len) && writebuf_put(wb, value, length);
 330 }
 331
 332 static int writebuf_string(struct writebuf *wb, const char *value)
 333 {
 334         return writebuf_string_length(wb, value, strlen(value));
 335 }
 336
 337 static int writebuf_nullstring(struct writebuf *wb, const char *value)
 338 {
 339         return value ? writebuf_string_length(wb, value, strlen(value)) : writebuf_uint32(wb, 0);
 340 }
 341
 342 static int writebuf_object(struct writebuf *wb, struct json_object *object)
 343 {
 344         const char *string = json_object_to_json_string_ext(object, JSON_C_TO_STRING_PLAIN);
 345         return string != NULL && writebuf_string(wb, string);
 346 }
 347
 348 /******************* queuing of messages *****************/
 349
 350 /* queue the processing of the received message (except if size=0 cause it's not a valid message) */
 351 static void queue_message_processing(struct afb_proto_ws *protows, char *data, size_t size, void (*processing)(int,void*))
 352 {
 353         struct binary *binary;
 354
 355         if (size) {
 356                 binary = malloc(sizeof *binary);
 357                 if (!binary) {
 358                         /* TODO process the problem */
 359                         errno = ENOMEM;
 360                 } else {
 361                         binary->protows = protows;
 362                         binary->rb.base = data;
 363                         binary->rb.head = data;
 364                         binary->rb.end = data + size;
 365                         if (!protows->queuing
 366                          || protows->queuing(protows, processing, binary) < 0)
 367                                 processing(0, binary);
 368                         return;
 369                 }
 370         }
 371         free(data);
 372 }
 373
 374 /******************* sending messages *****************/
 375
 376 static int proto_write(struct afb_proto_ws *protows, struct writebuf *wb)
 377 {
 378         int rc;
 379         struct afb_ws *ws;
 380
 381         pthread_mutex_lock(&protows->mutex);
 382         ws = protows->ws;
 383         if (ws == NULL) {
 384                 errno = EPIPE;
 385                 rc = -1;
 386         } else {
 387                 rc = afb_ws_binary_v(ws, wb->iovec, wb->iovcount);
 388                 if (rc > 0)
 389                         rc = 0;
 390         }
 391         pthread_mutex_unlock(&protows->mutex);
 392         return rc;
 393 }
 394
 395 /******************* ws request part for server *****************/
 396
 397 void afb_proto_ws_call_addref(struct afb_proto_ws_call *call)
 398 {
 399         __atomic_add_fetch(&call->refcount, 1, __ATOMIC_RELAXED);
 400 }
 401
 402 void afb_proto_ws_call_unref(struct afb_proto_ws_call *call)
 403 {
 404         if (__atomic_sub_fetch(&call->refcount, 1, __ATOMIC_RELAXED))
 405                 return;
 406
 407         afb_proto_ws_unref(call->protows);
 408         free(call->buffer);
 409         free(call);
 410 }
 411
 412 int afb_proto_ws_call_reply(struct afb_proto_ws_call *call, struct json_object *obj, const char *error, const char *info)
 413 {
 414         int rc = -1;
 415         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
 416         struct afb_proto_ws *protows = call->protows;
 417
 418         if (writebuf_char(&wb, CHAR_FOR_REPLY)
 419          && writebuf_uint32(&wb, call->callid)
 420          && writebuf_nullstring(&wb, error)
 421          && writebuf_nullstring(&wb, info)
 422          && writebuf_object(&wb, obj))
 423                 rc = proto_write(protows, &wb);
 424         return rc;
 425 }
 426
 427 int afb_proto_ws_call_subscribe(struct afb_proto_ws_call *call, const char *event_name, int event_id)
 428 {
 429         int rc = -1;
 430         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
 431         struct afb_proto_ws *protows = call->protows;
 432
 433         if (writebuf_char(&wb, CHAR_FOR_EVT_SUBSCRIBE)
 434          && writebuf_uint32(&wb, call->callid)
 435          && writebuf_uint32(&wb, (uint32_t)event_id)
 436          && writebuf_string(&wb, event_name))
 437                 rc = proto_write(protows, &wb);
 438         return rc;
 439 }
 440
 441 int afb_proto_ws_call_unsubscribe(struct afb_proto_ws_call *call, const char *event_name, int event_id)
 442 {
 443         int rc = -1;
 444         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
 445         struct afb_proto_ws *protows = call->protows;
 446
 447         if (writebuf_char(&wb, CHAR_FOR_EVT_UNSUBSCRIBE)
 448          && writebuf_uint32(&wb, call->callid)
 449          && writebuf_uint32(&wb, (uint32_t)event_id)
 450          && writebuf_string(&wb, event_name))
 451                 rc = proto_write(protows, &wb);
 452         return rc;
 453 }
 454
 455 /******************* client part **********************************/
 456
 457 /* search a memorized call */
 458 static struct client_call *client_call_search_locked(struct afb_proto_ws *protows, uint32_t callid)
 459 {
 460         struct client_call *call;
 461
 462         call = protows->calls;
 463         while (call != NULL && call->callid != callid)
 464                 call = call->next;
 465
 466         return call;
 467 }
 468
 469 static struct client_call *client_call_search_unlocked(struct afb_proto_ws *protows, uint32_t callid)
 470 {
 471         struct client_call *result;
 472
 473         pthread_mutex_lock(&protows->mutex);
 474         result = client_call_search_locked(protows, callid);
 475         pthread_mutex_unlock(&protows->mutex);
 476         return result;
 477 }
 478
 479 /* free and release the memorizing call */
 480 static void client_call_destroy(struct client_call *call)
 481 {
 482         struct client_call **prv;
 483         struct afb_proto_ws *protows = call->protows;
 484
 485         pthread_mutex_lock(&protows->mutex);
 486         prv = &call->protows->calls;
 487         while (*prv != NULL) {
 488                 if (*prv == call) {
 489                         *prv = call->next;
 490                         break;
 491                 }
 492                 prv = &(*prv)->next;
 493         }
 494         pthread_mutex_unlock(&protows->mutex);
 495         free(call);
 496 }
 497
 498 /* get event data from the message */
 499 static int client_msg_event_read(struct readbuf *rb, uint32_t *eventid, const char **name)
 500 {
 501         return readbuf_uint32(rb, eventid) && readbuf_string(rb, name, NULL);
 502 }
 503
 504 /* get event from the message */
 505 static int client_msg_call_get(struct afb_proto_ws *protows, struct readbuf *rb, struct client_call **call)
 506 {
 507         uint32_t callid;
 508
 509         /* get event data from the message */
 510         if (!readbuf_uint32(rb, &callid)) {
 511                 return 0;
 512         }
 513
 514         /* get the call */
 515         *call = client_call_search_unlocked(protows, callid);
 516         if (*call == NULL) {
 517                 return 0;
 518         }
 519
 520         return 1;
 521 }
 522
 523 /* adds an event */
 524 static void client_on_event_create(struct afb_proto_ws *protows, struct readbuf *rb)
 525 {
 526         const char *event_name;
 527         uint32_t event_id;
 528
 529         if (protows->client_itf->on_event_create && client_msg_event_read(rb, &event_id, &event_name))
 530                 protows->client_itf->on_event_create(protows->closure, event_name, (int)event_id);
 531         else
 532                 ERROR("Ignoring creation of event");
 533 }
 534
 535 /* removes an event */
 536 static void client_on_event_remove(struct afb_proto_ws *protows, struct readbuf *rb)
 537 {
 538         const char *event_name;
 539         uint32_t event_id;
 540
 541         if (protows->client_itf->on_event_remove && client_msg_event_read(rb, &event_id, &event_name))
 542                 protows->client_itf->on_event_remove(protows->closure, event_name, (int)event_id);
 543         else
 544                 ERROR("Ignoring deletion of event");
 545 }
 546
 547 /* subscribes an event */
 548 static void client_on_event_subscribe(struct afb_proto_ws *protows, struct readbuf *rb)
 549 {
 550         const char *event_name;
 551         uint32_t event_id;
 552         struct client_call *call;
 553
 554         if (protows->client_itf->on_event_subscribe && client_msg_call_get(protows, rb, &call) && client_msg_event_read(rb, &event_id, &event_name))
 555                 protows->client_itf->on_event_subscribe(protows->closure, call->request, event_name, (int)event_id);
 556         else
 557                 ERROR("Ignoring subscription to event");
 558 }
 559
 560 /* unsubscribes an event */
 561 static void client_on_event_unsubscribe(struct afb_proto_ws *protows, struct readbuf *rb)
 562 {
 563         const char *event_name;
 564         uint32_t event_id;
 565         struct client_call *call;
 566
 567         if (protows->client_itf->on_event_unsubscribe && client_msg_call_get(protows, rb, &call) && client_msg_event_read(rb, &event_id, &event_name))
 568                 protows->client_itf->on_event_unsubscribe(protows->closure, call->request, event_name, (int)event_id);
 569         else
 570                 ERROR("Ignoring unsubscription to event");
 571 }
 572
 573 /* receives broadcasted events */
 574 static void client_on_event_broadcast(struct afb_proto_ws *protows, struct readbuf *rb)
 575 {
 576         const char *event_name, *uuid;
 577         char hop;
 578         struct json_object *object;
 579
 580         if (protows->client_itf->on_event_broadcast && readbuf_string(rb, &event_name, NULL) && readbuf_object(rb, &object) && (uuid = readbuf_get(rb, 16)) && readbuf_char(rb, &hop))
 581                 protows->client_itf->on_event_broadcast(protows->closure, event_name, object, (unsigned char*)uuid, (uint8_t)hop);
 582         else
 583                 ERROR("Ignoring broadcast of event");
 584 }
 585
 586 /* pushs an event */
 587 static void client_on_event_push(struct afb_proto_ws *protows, struct readbuf *rb)
 588 {
 589         const char *event_name;
 590         uint32_t event_id;
 591         struct json_object *object;
 592
 593         if (protows->client_itf->on_event_push && client_msg_event_read(rb, &event_id, &event_name) && readbuf_object(rb, &object))
 594                 protows->client_itf->on_event_push(protows->closure, event_name, (int)event_id, object);
 595         else
 596                 ERROR("Ignoring push of event");
 597 }
 598
 599 static void client_on_reply(struct afb_proto_ws *protows, struct readbuf *rb)
 600 {
 601         struct client_call *call;
 602         struct json_object *object;
 603         const char *error, *info;
 604
 605         if (!client_msg_call_get(protows, rb, &call))
 606                 return;
 607
 608         if (readbuf_nullstring(rb, &error, NULL) && readbuf_nullstring(rb, &info, NULL) && readbuf_object(rb, &object)) {
 609                 protows->client_itf->on_reply(protows->closure, call->request, object, error, info);
 610         } else {
 611                 protows->client_itf->on_reply(protows->closure, call->request, NULL, "proto-error", "can't process success");
 612         }
 613         client_call_destroy(call);
 614 }
 615
 616 static void client_on_description(struct afb_proto_ws *protows, struct readbuf *rb)
 617 {
 618         uint32_t descid;
 619         struct client_describe *desc, **prv;
 620         struct json_object *object;
 621
 622         if (readbuf_uint32(rb, &descid)) {
 623                 pthread_mutex_lock(&protows->mutex);
 624                 prv = &protows->describes;
 625                 while ((desc = *prv) && desc->descid != descid)
 626                         prv = &desc->next;
 627                 if (!desc)
 628                         pthread_mutex_unlock(&protows->mutex);
 629                 else {
 630                         *prv = desc->next;
 631                         pthread_mutex_unlock(&protows->mutex);
 632                         if (!readbuf_object(rb, &object))
 633                                 object = NULL;
 634                         desc->callback(desc->closure, object);
 635                         free(desc);
 636                 }
 637         }
 638 }
 639
 640 /* callback when receiving binary data */
 641 static void client_on_binary_job(int sig, void *closure)
 642 {
 643         struct binary *binary = closure;
 644
 645         if (!sig) {
 646                 switch (*binary->rb.head++) {
 647                 case CHAR_FOR_REPLY: /* reply */
 648                         client_on_reply(binary->protows, &binary->rb);
 649                         break;
 650                 case CHAR_FOR_EVT_BROADCAST: /* broadcast */
 651                         client_on_event_broadcast(binary->protows, &binary->rb);
 652                         break;
 653                 case CHAR_FOR_EVT_ADD: /* creates the event */
 654                         client_on_event_create(binary->protows, &binary->rb);
 655                         break;
 656                 case CHAR_FOR_EVT_DEL: /* removes the event */
 657                         client_on_event_remove(binary->protows, &binary->rb);
 658                         break;
 659                 case CHAR_FOR_EVT_PUSH: /* pushs the event */
 660                         client_on_event_push(binary->protows, &binary->rb);
 661                         break;
 662                 case CHAR_FOR_EVT_SUBSCRIBE: /* subscribe event for a request */
 663                         client_on_event_subscribe(binary->protows, &binary->rb);
 664                         break;
 665                 case CHAR_FOR_EVT_UNSUBSCRIBE: /* unsubscribe event for a request */
 666                         client_on_event_unsubscribe(binary->protows, &binary->rb);
 667                         break;
 668                 case CHAR_FOR_DESCRIPTION: /* description */
 669                         client_on_description(binary->protows, &binary->rb);
 670                         break;
 671                 default: /* unexpected message */
 672                         /* TODO: close the connection */
 673                         break;
 674                 }
 675         }
 676         free(binary->rb.base);
 677         free(binary);
 678 }
 679
 680 /* callback when receiving binary data */
 681 static void client_on_binary(void *closure, char *data, size_t size)
 682 {
 683         struct afb_proto_ws *protows = closure;
 684
 685         queue_message_processing(protows, data, size, client_on_binary_job);
 686 }
 687
 688 int afb_proto_ws_client_call(
 689                 struct afb_proto_ws *protows,
 690                 const char *verb,
 691                 struct json_object *args,
 692                 const char *sessionid,
 693                 void *request,
 694                 const char *user_creds
 695 )
 696 {
 697         int rc = -1;
 698         struct client_call *call;
 699         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
 700
 701         /* allocate call data */
 702         call = malloc(sizeof *call);
 703         if (call == NULL) {
 704                 errno = ENOMEM;
 705                 return -1;
 706         }
 707         call->request = request;
 708
 709         /* init call data */
 710         pthread_mutex_lock(&protows->mutex);
 711         call->callid = ptr2id(call);
 712         while(client_call_search_locked(protows, call->callid) != NULL)
 713                 call->callid++;
 714         call->protows = protows;
 715         call->next = protows->calls;
 716         protows->calls = call;
 717         pthread_mutex_unlock(&protows->mutex);
 718
 719         /* creates the call message */
 720         if (!writebuf_char(&wb, CHAR_FOR_CALL)
 721          || !writebuf_uint32(&wb, call->callid)
 722          || !writebuf_string(&wb, verb)
 723          || !writebuf_string(&wb, sessionid)
 724          || !writebuf_object(&wb, args)
 725          || !writebuf_nullstring(&wb, user_creds)) {
 726                 errno = EINVAL;
 727                 goto clean;
 728         }
 729
 730         /* send */
 731         rc = proto_write(protows, &wb);
 732         if (!rc)
 733                 goto end;
 734
 735 clean:
 736         client_call_destroy(call);
 737 end:
 738         return rc;
 739 }
 740
 741 /* get the description */
 742 int afb_proto_ws_client_describe(struct afb_proto_ws *protows, void (*callback)(void*, struct json_object*), void *closure)
 743 {
 744         struct client_describe *desc, *d;
 745         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
 746
 747         desc = malloc(sizeof *desc);
 748         if (!desc) {
 749                 errno = ENOMEM;
 750                 goto error;
 751         }
 752
 753         /* fill in stack the description of the task */
 754         pthread_mutex_lock(&protows->mutex);
 755         desc->descid = ptr2id(desc);
 756         d = protows->describes;
 757         while (d) {
 758                 if (d->descid != desc->descid)
 759                         d = d->next;
 760                 else {
 761                         desc->descid++;
 762                         d = protows->describes;
 763                 }
 764         }
 765         desc->callback = callback;
 766         desc->closure = closure;
 767         desc->protows = protows;
 768         desc->next = protows->describes;
 769         protows->describes = desc;
 770
 771         /* send */
 772         if (writebuf_char(&wb, CHAR_FOR_DESCRIBE)
 773          && writebuf_uint32(&wb, desc->descid)
 774          && protows->ws != NULL
 775          && afb_ws_binary_v(protows->ws, wb.iovec, wb.iovcount) >= 0) {
 776                 pthread_mutex_unlock(&protows->mutex);
 777                 return 0;
 778         }
 779
 780         d = protows->describes;
 781         if (d == desc)
 782                 protows->describes = desc->next;
 783         else {
 784                 while(d && d->next != desc)
 785                         d = d->next;
 786                 if (d)
 787                         d->next = desc->next;
 788         }
 789         pthread_mutex_unlock(&protows->mutex);
 790         free(desc);
 791 error:
 792         /* TODO? callback(closure, NULL); */
 793         return -1;
 794 }
 795
 796 /******************* client description part for server *****************************/
 797
 798 /* on call, propagate it to the ws service */
 799 static void server_on_call(struct afb_proto_ws *protows, struct readbuf *rb)
 800 {
 801         struct afb_proto_ws_call *call;
 802         const char *uuid, *verb, *user_creds;
 803         uint32_t callid;
 804         size_t lenverb;
 805         struct json_object *object;
 806
 807         afb_proto_ws_addref(protows);
 808
 809         /* reads the call message data */
 810         if (!readbuf_uint32(rb, &callid)
 811          || !readbuf_string(rb, &verb, &lenverb)
 812          || !readbuf_string(rb, &uuid, NULL)
 813          || !readbuf_object(rb, &object)
 814          || !readbuf_nullstring(rb, &user_creds, NULL))
 815                 goto overflow;
 816
 817         /* create the request */
 818         call = malloc(sizeof *call);
 819         if (call == NULL)
 820                 goto out_of_memory;
 821
 822         call->protows = protows;
 823         call->callid = callid;
 824         call->refcount = 1;
 825         call->buffer = rb->base;
 826         rb->base = NULL; /* don't free the buffer */
 827
 828         protows->server_itf->on_call(protows->closure, call, verb, object, uuid, user_creds);
 829         return;
 830
 831 out_of_memory:
 832         json_object_put(object);
 833
 834 overflow:
 835         afb_proto_ws_unref(protows);
 836 }
 837
 838 static int server_send_description(struct afb_proto_ws *protows, uint32_t descid, struct json_object *descobj)
 839 {
 840         int rc = -1;
 841         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
 842
 843         if (writebuf_char(&wb, CHAR_FOR_DESCRIPTION)
 844          && writebuf_uint32(&wb, descid)
 845          && writebuf_object(&wb, descobj))
 846                 rc = proto_write(protows, &wb);
 847         return rc;
 848 }
 849
 850 int afb_proto_ws_describe_put(struct afb_proto_ws_describe *describe, struct json_object *description)
 851 {
 852         int rc = server_send_description(describe->protows, describe->descid, description);
 853         afb_proto_ws_unref(describe->protows);
 854         free(describe);
 855         return rc;
 856 }
 857
 858 /* on describe, propagate it to the ws service */
 859 static void server_on_describe(struct afb_proto_ws *protows, struct readbuf *rb)
 860 {
 861         uint32_t descid;
 862         struct afb_proto_ws_describe *desc;
 863
 864         /* reads the descid */
 865         if (readbuf_uint32(rb, &descid)) {
 866                 if (protows->server_itf->on_describe) {
 867                         /* create asynchronous job */
 868                         desc = malloc(sizeof *desc);
 869                         if (desc) {
 870                                 desc->descid = descid;
 871                                 desc->protows = protows;
 872                                 afb_proto_ws_addref(protows);
 873                                 protows->server_itf->on_describe(protows->closure, desc);
 874                                 return;
 875                         }
 876                 }
 877                 server_send_description(protows, descid, NULL);
 878         }
 879 }
 880
 881 /* callback when receiving binary data */
 882 static void server_on_binary_job(int sig, void *closure)
 883 {
 884         struct binary *binary = closure;
 885
 886         if (!sig) {
 887                 switch (*binary->rb.head++) {
 888                 case CHAR_FOR_CALL:
 889                         server_on_call(binary->protows, &binary->rb);
 890                         break;
 891                 case CHAR_FOR_DESCRIBE:
 892                         server_on_describe(binary->protows, &binary->rb);
 893                         break;
 894                 default: /* unexpected message */
 895                         /* TODO: close the connection */
 896                         break;
 897                 }
 898         }
 899         free(binary->rb.base);
 900         free(binary);
 901 }
 902
 903 static void server_on_binary(void *closure, char *data, size_t size)
 904 {
 905         struct afb_proto_ws *protows = closure;
 906
 907         queue_message_processing(protows, data, size, server_on_binary_job);
 908 }
 909
 910 /******************* server part: manage events **********************************/
 911
 912 static int server_event_send(struct afb_proto_ws *protows, char order, const char *event_name, int event_id, struct json_object *data)
 913 {
 914         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
 915         int rc = -1;
 916
 917         if (writebuf_char(&wb, order)
 918          && writebuf_uint32(&wb, event_id)
 919          && writebuf_string(&wb, event_name)
 920          && (order != CHAR_FOR_EVT_PUSH || writebuf_object(&wb, data)))
 921                 rc = proto_write(protows, &wb);
 922         return rc;
 923 }
 924
 925 int afb_proto_ws_server_event_create(struct afb_proto_ws *protows, const char *event_name, int event_id)
 926 {
 927         return server_event_send(protows, CHAR_FOR_EVT_ADD, event_name, event_id, NULL);
 928 }
 929
 930 int afb_proto_ws_server_event_remove(struct afb_proto_ws *protows, const char *event_name, int event_id)
 931 {
 932         return server_event_send(protows, CHAR_FOR_EVT_DEL, event_name, event_id, NULL);
 933 }
 934
 935 int afb_proto_ws_server_event_push(struct afb_proto_ws *protows, const char *event_name, int event_id, struct json_object *data)
 936 {
 937         return server_event_send(protows, CHAR_FOR_EVT_PUSH, event_name, event_id, data);
 938 }
 939
 940 int afb_proto_ws_server_event_broadcast(struct afb_proto_ws *protows, const char *event_name, struct json_object *data, const unsigned char uuid[16], uint8_t hop)
 941 {
 942         struct writebuf wb = { .iovcount = 0, .bufcount = 0 };
 943         int rc = -1;
 944
 945         if (!hop)
 946                 return 0;
 947
 948         if (writebuf_char(&wb, CHAR_FOR_EVT_BROADCAST)
 949          && writebuf_string(&wb, event_name)
 950          && writebuf_object(&wb, data)
 951          && writebuf_put(&wb, uuid, 16)
 952          && writebuf_char(&wb, (char)(hop - 1)))
 953                 rc = proto_write(protows, &wb);
 954         return rc;
 955 }
 956
 957 /*****************************************************/
 958
 959 /* callback when receiving a hangup */
 960 static void on_hangup(void *closure)
 961 {
 962         struct afb_proto_ws *protows = closure;
 963         struct client_describe *cd, *ncd;
 964         struct client_call *call, *ncall;
 965         struct afb_ws *ws;
 966
 967         pthread_mutex_lock(&protows->mutex);
 968         ncd = protows->describes;
 969         protows->describes = NULL;
 970         ncall = protows->calls;
 971         protows->calls = NULL;
 972         ws = protows->ws;
 973         protows->ws = NULL;
 974         pthread_mutex_unlock(&protows->mutex);
 975
 976         while (ncall) {
 977                 call= ncall;
 978                 ncall = call->next;
 979                 protows->client_itf->on_reply(protows->closure, call->request, NULL, "disconnected", "server hung up");
 980                 free(call);
 981         }
 982
 983         while (ncd) {
 984                 cd= ncd;
 985                 ncd = cd->next;
 986                 cd->callback(cd->closure, NULL);
 987                 free(cd);
 988         }
 989
 990         if (ws) {
 991                 afb_ws_destroy(ws);
 992                 if (protows->on_hangup)
 993                         protows->on_hangup(protows->closure);
 994         }
 995 }
 996
 997 /*****************************************************/
 998
 999 static const struct afb_ws_itf proto_ws_client_ws_itf =
1000 {
1001         .on_close = NULL,
1002         .on_text = NULL,
1003         .on_binary = client_on_binary,
1004         .on_error = NULL,
1005         .on_hangup = on_hangup
1006 };
1007
1008 static const struct afb_ws_itf server_ws_itf =
1009 {
1010         .on_close = NULL,
1011         .on_text = NULL,
1012         .on_binary = server_on_binary,
1013         .on_error = NULL,
1014         .on_hangup = on_hangup
1015 };
1016
1017 /*****************************************************/
1018
1019 static struct afb_proto_ws *afb_proto_ws_create(struct fdev *fdev, const struct afb_proto_ws_server_itf *itfs, const struct afb_proto_ws_client_itf *itfc, void *closure, const struct afb_ws_itf *itf)
1020 {
1021         struct afb_proto_ws *protows;
1022
1023         protows = calloc(1, sizeof *protows);
1024         if (protows == NULL)
1025                 errno = ENOMEM;
1026         else {
1027                 fcntl(fdev_fd(fdev), F_SETFD, FD_CLOEXEC);
1028                 fcntl(fdev_fd(fdev), F_SETFL, O_NONBLOCK);
1029                 protows->ws = afb_ws_create(fdev, itf, protows);
1030                 if (protows->ws != NULL) {
1031                         protows->refcount = 1;
1032                         protows->closure = closure;
1033                         protows->server_itf = itfs;
1034                         protows->client_itf = itfc;
1035                         pthread_mutex_init(&protows->mutex, NULL);
1036                         return protows;
1037                 }
1038                 free(protows);
1039         }
1040         return NULL;
1041 }
1042
1043 struct afb_proto_ws *afb_proto_ws_create_client(struct fdev *fdev, const struct afb_proto_ws_client_itf *itf, void *closure)
1044 {
1045         return afb_proto_ws_create(fdev, NULL, itf, closure, &proto_ws_client_ws_itf);
1046 }
1047
1048 struct afb_proto_ws *afb_proto_ws_create_server(struct fdev *fdev, const struct afb_proto_ws_server_itf *itf, void *closure)
1049 {
1050         return afb_proto_ws_create(fdev, itf, NULL, closure, &server_ws_itf);
1051 }
1052
1053 void afb_proto_ws_unref(struct afb_proto_ws *protows)
1054 {
1055         if (protows && !__atomic_sub_fetch(&protows->refcount, 1, __ATOMIC_RELAXED)) {
1056                 afb_proto_ws_hangup(protows);
1057                 pthread_mutex_destroy(&protows->mutex);
1058                 free(protows);
1059         }
1060 }
1061
1062 void afb_proto_ws_addref(struct afb_proto_ws *protows)
1063 {
1064         __atomic_add_fetch(&protows->refcount, 1, __ATOMIC_RELAXED);
1065 }
1066
1067 int afb_proto_ws_is_client(struct afb_proto_ws *protows)
1068 {
1069         return !!protows->client_itf;
1070 }
1071
1072 int afb_proto_ws_is_server(struct afb_proto_ws *protows)
1073 {
1074         return !!protows->server_itf;
1075 }
1076
1077 void afb_proto_ws_hangup(struct afb_proto_ws *protows)
1078 {
1079         if (protows->ws)
1080                 afb_ws_hangup(protows->ws);
1081 }
1082
1083 void afb_proto_ws_on_hangup(struct afb_proto_ws *protows, void (*on_hangup)(void *closure))
1084 {
1085         protows->on_hangup = on_hangup;
1086 }
1087
1088 void afb_proto_ws_set_queuing(struct afb_proto_ws *protows, int (*queuing)(struct afb_proto_ws*, void (*)(int,void*), void*))
1089 {
1090         protows->queuing = queuing;
1091 }