src/afb-proto-ws.c

   1 /*
   2  * Copyright (C) 2015-2018 "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 "jobs.h"
  39 #include "fdev.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;
  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         /* file descriptor */
 136         struct fdev *fdev;
 137
 138         /* resource control */
 139         pthread_mutex_t mutex;
 140
 141         /* websocket */
 142         struct afb_ws *ws;
 143
 144         /* the client closure */
 145         void *closure;
 146
 147         /* the client side interface */
 148         const struct afb_proto_ws_client_itf *client_itf;
 149
 150         /* the server side interface */
 151         const struct afb_proto_ws_server_itf *server_itf;
 152
 153         /* emitted calls (client side) */
 154         struct client_call *calls;
 155
 156         /* pending description (client side) */
 157         struct client_describe *describes;
 158
 159         /* on hangup callback */
 160         void (*on_hangup)(void *closure);
 161
 162         /* queuing facility for processing messages */
 163         int (*queuing)(void (*process)(int s, void *c), void *closure);
 164 };
 165
 166 /******************* streaming objects **********************************/
 167
 168 #define WRITEBUF_COUNT_MAX  32
 169 struct writebuf
 170 {
 171         struct iovec iovec[WRITEBUF_COUNT_MAX];
 172         uint32_t uints[WRITEBUF_COUNT_MAX];
 173         int count;
 174 };
 175
 176 struct readbuf
 177 {
 178         char *base, *head, *end;
 179 };
 180
 181 struct binary
 182 {
 183         struct afb_proto_ws *protows;
 184         struct readbuf rb;
 185 };
 186
 187 /******************* common useful tools **********************************/
 188
 189 /**
 190  * translate a pointer to some integer
 191  * @param ptr the pointer to translate
 192  * @return an integer
 193  */
 194 static inline uint32_t ptr2id(void *ptr)
 195 {
 196         return (uint32_t)(((intptr_t)ptr) >> 6);
 197 }
 198
 199 /******************* serialisation part **********************************/
 200
 201 static char *readbuf_get(struct readbuf *rb, uint32_t length)
 202 {
 203         char *before = rb->head;
 204         char *after = before + length;
 205         if (after > rb->end)
 206                 return 0;
 207         rb->head = after;
 208         return before;
 209 }
 210
 211 __attribute__((unused))
 212 static int readbuf_char(struct readbuf *rb, char *value)
 213 {
 214         if (rb->head >= rb->end)
 215                 return 0;
 216         *value = *rb->head++;
 217         return 1;
 218 }
 219
 220 static int readbuf_uint32(struct readbuf *rb, uint32_t *value)
 221 {
 222         char *after = rb->head + sizeof *value;
 223         if (after > rb->end)
 224                 return 0;
 225         memcpy(value, rb->head, sizeof *value);
 226         rb->head = after;
 227         *value = le32toh(*value);
 228         return 1;
 229 }
 230
 231 static int _readbuf_string_(struct readbuf *rb, const char **value, size_t *length, int nulok)
 232 {
 233         uint32_t len;
 234         if (!readbuf_uint32(rb, &len))
 235                 return 0;
 236         if (!len) {
 237                 if (!nulok)
 238                         return 0;
 239                 *value = NULL;
 240                 if (length)
 241                         *length = 0;
 242                 return 1;
 243         }
 244         if (length)
 245                 *length = (size_t)(len - 1);
 246         return (*value = readbuf_get(rb, len)) != NULL &&  rb->head[-1] == 0;
 247 }
 248
 249
 250 static int readbuf_string(struct readbuf *rb, const char **value, size_t *length)
 251 {
 252         return _readbuf_string_(rb, value, length, 0);
 253 }
 254
 255 static int readbuf_nullstring(struct readbuf *rb, const char **value, size_t *length)
 256 {
 257         return _readbuf_string_(rb, value, length, 1);
 258 }
 259
 260 static int readbuf_object(struct readbuf *rb, struct json_object **object)
 261 {
 262         const char *string;
 263         struct json_object *o;
 264         int rc = readbuf_string(rb, &string, NULL);
 265         if (rc) {
 266                 o = json_tokener_parse(string);
 267                 if (o == NULL && strcmp(string, "null"))
 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->count;
 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->count = i + 1;
 282         return 1;
 283 }
 284
 285 static int writebuf_char(struct writebuf *wb, char value)
 286 {
 287         int i = wb->count;
 288         if (i == WRITEBUF_COUNT_MAX)
 289                 return 0;
 290         *(char*)&wb->uints[i] = value;
 291         wb->iovec[i].iov_base = &wb->uints[i];
 292         wb->iovec[i].iov_len = 1;
 293         wb->count = i + 1;
 294         return 1;
 295 }
 296
 297 static int writebuf_uint32(struct writebuf *wb, uint32_t value)
 298 {
 299         int i = wb->count;
 300         if (i == WRITEBUF_COUNT_MAX)
 301                 return 0;
 302         wb->uints[i] = htole32(value);
 303         wb->iovec[i].iov_base = &wb->uints[i];
 304         wb->iovec[i].iov_len = sizeof wb->uints[i];
 305         wb->count = i + 1;
 306         return 1;
 307 }
 308
 309 static int writebuf_string_length(struct writebuf *wb, const char *value, size_t length)
 310 {
 311         uint32_t len = (uint32_t)++length;
 312         return (size_t)len == length && len && writebuf_uint32(wb, len) && writebuf_put(wb, value, length);
 313 }
 314
 315 static int writebuf_string(struct writebuf *wb, const char *value)
 316 {
 317         return writebuf_string_length(wb, value, strlen(value));
 318 }
 319
 320 static int writebuf_nullstring(struct writebuf *wb, const char *value)
 321 {
 322         return value ? writebuf_string_length(wb, value, strlen(value)) : writebuf_uint32(wb, 0);
 323 }
 324
 325 static int writebuf_object(struct writebuf *wb, struct json_object *object)
 326 {
 327         const char *string = json_object_to_json_string_ext(object, JSON_C_TO_STRING_PLAIN);
 328         return string != NULL && writebuf_string(wb, string);
 329 }
 330
 331 /******************* queuing of messages *****************/
 332
 333 /* queue the processing of the received message (except if size=0 cause it's not a valid message) */
 334 static void queue_message_processing(struct afb_proto_ws *protows, char *data, size_t size, void (*processing)(int,void*))
 335 {
 336         struct binary *binary;
 337
 338         if (size) {
 339                 binary = malloc(sizeof *binary);
 340                 if (!binary) {
 341                         /* TODO process the problem */
 342                         errno = ENOMEM;
 343                 } else {
 344                         binary->protows = protows;
 345                         binary->rb.base = data;
 346                         binary->rb.head = data;
 347                         binary->rb.end = data + size;
 348                         if (!protows->queuing
 349                          || protows->queuing(processing, binary) < 0)
 350                                 processing(0, binary);
 351                         return;
 352                 }
 353         }
 354         free(data);
 355 }
 356
 357 /******************* ws request part for server *****************/
 358
 359 void afb_proto_ws_call_addref(struct afb_proto_ws_call *call)
 360 {
 361         __atomic_add_fetch(&call->refcount, 1, __ATOMIC_RELAXED);
 362 }
 363
 364 void afb_proto_ws_call_unref(struct afb_proto_ws_call *call)
 365 {
 366         if (__atomic_sub_fetch(&call->refcount, 1, __ATOMIC_RELAXED))
 367                 return;
 368
 369         afb_proto_ws_unref(call->protows);
 370         free(call->buffer);
 371         free(call);
 372 }
 373
 374 int afb_proto_ws_call_reply(struct afb_proto_ws_call *call, struct json_object *obj, const char *error, const char *info)
 375 {
 376         int rc = -1;
 377         struct writebuf wb = { .count = 0 };
 378         struct afb_proto_ws *protows = call->protows;
 379
 380         if (writebuf_char(&wb, CHAR_FOR_REPLY)
 381          && writebuf_uint32(&wb, call->callid)
 382          && writebuf_nullstring(&wb, error)
 383          && writebuf_nullstring(&wb, info)
 384          && writebuf_object(&wb, obj)) {
 385                 pthread_mutex_lock(&protows->mutex);
 386                 rc = afb_ws_binary_v(protows->ws, wb.iovec, wb.count);
 387                 pthread_mutex_unlock(&protows->mutex);
 388                 if (rc >= 0) {
 389                         rc = 0;
 390                         goto success;
 391                 }
 392         }
 393 success:
 394         return rc;
 395 }
 396
 397 int afb_proto_ws_call_subscribe(struct afb_proto_ws_call *call, const char *event_name, int event_id)
 398 {
 399         int rc = -1;
 400         struct writebuf wb = { .count = 0 };
 401         struct afb_proto_ws *protows = call->protows;
 402
 403         if (writebuf_char(&wb, CHAR_FOR_EVT_SUBSCRIBE)
 404          && writebuf_uint32(&wb, call->callid)
 405          && writebuf_uint32(&wb, (uint32_t)event_id)
 406          && writebuf_string(&wb, event_name)) {
 407                 pthread_mutex_lock(&protows->mutex);
 408                 rc = afb_ws_binary_v(protows->ws, wb.iovec, wb.count);
 409                 pthread_mutex_unlock(&protows->mutex);
 410                 if (rc >= 0) {
 411                         rc = 0;
 412                         goto success;
 413                 }
 414         }
 415 success:
 416         return rc;
 417 }
 418
 419 int afb_proto_ws_call_unsubscribe(struct afb_proto_ws_call *call, const char *event_name, int event_id)
 420 {
 421         int rc = -1;
 422         struct writebuf wb = { .count = 0 };
 423         struct afb_proto_ws *protows = call->protows;
 424
 425         if (writebuf_char(&wb, CHAR_FOR_EVT_UNSUBSCRIBE)
 426          && writebuf_uint32(&wb, call->callid)
 427          && writebuf_uint32(&wb, (uint32_t)event_id)
 428          && writebuf_string(&wb, event_name)) {
 429                 pthread_mutex_lock(&protows->mutex);
 430                 rc = afb_ws_binary_v(protows->ws, wb.iovec, wb.count);
 431                 pthread_mutex_unlock(&protows->mutex);
 432                 if (rc >= 0) {
 433                         rc = 0;
 434                         goto success;
 435                 }
 436         }
 437 success:
 438         return rc;
 439 }
 440
 441 /******************* client part **********************************/
 442
 443 /* search a memorized call */
 444 static struct client_call *client_call_search_locked(struct afb_proto_ws *protows, uint32_t callid)
 445 {
 446         struct client_call *call;
 447
 448         call = protows->calls;
 449         while (call != NULL && call->callid != callid)
 450                 call = call->next;
 451
 452         return call;
 453 }
 454
 455 static struct client_call *client_call_search_unlocked(struct afb_proto_ws *protows, uint32_t callid)
 456 {
 457         struct client_call *result;
 458
 459         pthread_mutex_lock(&protows->mutex);
 460         result = client_call_search_locked(protows, callid);
 461         pthread_mutex_unlock(&protows->mutex);
 462         return result;
 463 }
 464
 465 /* free and release the memorizing call */
 466 static void client_call_destroy(struct client_call *call)
 467 {
 468         struct client_call **prv;
 469         struct afb_proto_ws *protows = call->protows;
 470
 471         pthread_mutex_lock(&protows->mutex);
 472         prv = &call->protows->calls;
 473         while (*prv != NULL) {
 474                 if (*prv == call) {
 475                         *prv = call->next;
 476                         break;
 477                 }
 478                 prv = &(*prv)->next;
 479         }
 480         pthread_mutex_unlock(&protows->mutex);
 481         free(call);
 482 }
 483
 484 /* get event data from the message */
 485 static int client_msg_event_read(struct readbuf *rb, uint32_t *eventid, const char **name)
 486 {
 487         return readbuf_uint32(rb, eventid) && readbuf_string(rb, name, NULL);
 488 }
 489
 490 /* get event from the message */
 491 static int client_msg_call_get(struct afb_proto_ws *protows, struct readbuf *rb, struct client_call **call)
 492 {
 493         uint32_t callid;
 494
 495         /* get event data from the message */
 496         if (!readbuf_uint32(rb, &callid)) {
 497                 return 0;
 498         }
 499
 500         /* get the call */
 501         *call = client_call_search_unlocked(protows, callid);
 502         if (*call == NULL) {
 503                 return 0;
 504         }
 505
 506         return 1;
 507 }
 508
 509 /* adds an event */
 510 static void client_on_event_create(struct afb_proto_ws *protows, struct readbuf *rb)
 511 {
 512         const char *event_name;
 513         uint32_t event_id;
 514
 515         if (protows->client_itf->on_event_create && client_msg_event_read(rb, &event_id, &event_name))
 516                 protows->client_itf->on_event_create(protows->closure, event_name, (int)event_id);
 517 }
 518
 519 /* removes an event */
 520 static void client_on_event_remove(struct afb_proto_ws *protows, struct readbuf *rb)
 521 {
 522         const char *event_name;
 523         uint32_t event_id;
 524
 525         if (protows->client_itf->on_event_remove && client_msg_event_read(rb, &event_id, &event_name))
 526                 protows->client_itf->on_event_remove(protows->closure, event_name, (int)event_id);
 527 }
 528
 529 /* subscribes an event */
 530 static void client_on_event_subscribe(struct afb_proto_ws *protows, struct readbuf *rb)
 531 {
 532         const char *event_name;
 533         uint32_t event_id;
 534         struct client_call *call;
 535
 536         if (protows->client_itf->on_event_subscribe && client_msg_call_get(protows, rb, &call) && client_msg_event_read(rb, &event_id, &event_name))
 537                 protows->client_itf->on_event_subscribe(protows->closure, call->request, event_name, (int)event_id);
 538 }
 539
 540 /* unsubscribes an event */
 541 static void client_on_event_unsubscribe(struct afb_proto_ws *protows, struct readbuf *rb)
 542 {
 543         const char *event_name;
 544         uint32_t event_id;
 545         struct client_call *call;
 546
 547         if (protows->client_itf->on_event_unsubscribe && client_msg_call_get(protows, rb, &call) && client_msg_event_read(rb, &event_id, &event_name))
 548                 protows->client_itf->on_event_unsubscribe(protows->closure, call->request, event_name, (int)event_id);
 549 }
 550
 551 /* receives broadcasted events */
 552 static void client_on_event_broadcast(struct afb_proto_ws *protows, struct readbuf *rb)
 553 {
 554         const char *event_name;
 555         struct json_object *object;
 556
 557         if (protows->client_itf->on_event_broadcast && readbuf_string(rb, &event_name, NULL) && readbuf_object(rb, &object))
 558                 protows->client_itf->on_event_broadcast(protows->closure, event_name, object);
 559 }
 560
 561 /* pushs an event */
 562 static void client_on_event_push(struct afb_proto_ws *protows, struct readbuf *rb)
 563 {
 564         const char *event_name;
 565         uint32_t event_id;
 566         struct json_object *object;
 567
 568         if (protows->client_itf->on_event_push && client_msg_event_read(rb, &event_id, &event_name) && readbuf_object(rb, &object))
 569                 protows->client_itf->on_event_push(protows->closure, event_name, (int)event_id, object);
 570 }
 571
 572 static void client_on_reply(struct afb_proto_ws *protows, struct readbuf *rb)
 573 {
 574         struct client_call *call;
 575         struct json_object *object;
 576         const char *error, *info;
 577
 578         if (!client_msg_call_get(protows, rb, &call))
 579                 return;
 580
 581         if (readbuf_nullstring(rb, &error, NULL) && readbuf_nullstring(rb, &info, NULL) && readbuf_object(rb, &object)) {
 582                 protows->client_itf->on_reply(protows->closure, call->request, object, error, info);
 583         } else {
 584                 protows->client_itf->on_reply(protows->closure, call->request, NULL, "proto-error", "can't process success");
 585         }
 586         client_call_destroy(call);
 587 }
 588
 589 static void client_on_description(struct afb_proto_ws *protows, struct readbuf *rb)
 590 {
 591         uint32_t descid;
 592         struct client_describe *desc, **prv;
 593         struct json_object *object;
 594
 595         if (readbuf_uint32(rb, &descid)) {
 596                 pthread_mutex_lock(&protows->mutex);
 597                 prv = &protows->describes;
 598                 while ((desc = *prv) && desc->descid != descid)
 599                         prv = &desc->next;
 600                 if (!desc)
 601                         pthread_mutex_unlock(&protows->mutex);
 602                 else {
 603                         *prv = desc->next;
 604                         pthread_mutex_unlock(&protows->mutex);
 605                         if (!readbuf_object(rb, &object))
 606                                 object = NULL;
 607                         desc->callback(desc->closure, object);
 608                         free(desc);
 609                 }
 610         }
 611 }
 612
 613 /* callback when receiving binary data */
 614 static void client_on_binary_job(int sig, void *closure)
 615 {
 616         struct binary *binary = closure;
 617
 618         if (!sig) {
 619                 switch (*binary->rb.head++) {
 620                 case CHAR_FOR_REPLY: /* reply */
 621                         client_on_reply(binary->protows, &binary->rb);
 622                         break;
 623                 case CHAR_FOR_EVT_BROADCAST: /* broadcast */
 624                         client_on_event_broadcast(binary->protows, &binary->rb);
 625                         break;
 626                 case CHAR_FOR_EVT_ADD: /* creates the event */
 627                         client_on_event_create(binary->protows, &binary->rb);
 628                         break;
 629                 case CHAR_FOR_EVT_DEL: /* removes the event */
 630                         client_on_event_remove(binary->protows, &binary->rb);
 631                         break;
 632                 case CHAR_FOR_EVT_PUSH: /* pushs the event */
 633                         client_on_event_push(binary->protows, &binary->rb);
 634                         break;
 635                 case CHAR_FOR_EVT_SUBSCRIBE: /* subscribe event for a request */
 636                         client_on_event_subscribe(binary->protows, &binary->rb);
 637                         break;
 638                 case CHAR_FOR_EVT_UNSUBSCRIBE: /* unsubscribe event for a request */
 639                         client_on_event_unsubscribe(binary->protows, &binary->rb);
 640                         break;
 641                 case CHAR_FOR_DESCRIPTION: /* description */
 642                         client_on_description(binary->protows, &binary->rb);
 643                         break;
 644                 default: /* unexpected message */
 645                         /* TODO: close the connection */
 646                         break;
 647                 }
 648         }
 649         free(binary->rb.base);
 650         free(binary);
 651 }
 652
 653 /* callback when receiving binary data */
 654 static void client_on_binary(void *closure, char *data, size_t size)
 655 {
 656         struct afb_proto_ws *protows = closure;
 657
 658         queue_message_processing(protows, data, size, client_on_binary_job);
 659 }
 660
 661 int afb_proto_ws_client_call(
 662                 struct afb_proto_ws *protows,
 663                 const char *verb,
 664                 struct json_object *args,
 665                 const char *sessionid,
 666                 void *request,
 667                 const char *user_creds
 668 )
 669 {
 670         int rc = -1;
 671         struct client_call *call;
 672         struct writebuf wb = { .count = 0 };
 673
 674         /* allocate call data */
 675         call = malloc(sizeof *call);
 676         if (call == NULL) {
 677                 errno = ENOMEM;
 678                 return -1;
 679         }
 680         call->request = request;
 681
 682         /* init call data */
 683         pthread_mutex_lock(&protows->mutex);
 684         call->callid = ptr2id(call);
 685         while(client_call_search_locked(protows, call->callid) != NULL)
 686                 call->callid++;
 687         call->protows = protows;
 688         call->next = protows->calls;
 689         protows->calls = call;
 690         pthread_mutex_unlock(&protows->mutex);
 691
 692         /* creates the call message */
 693         if (!writebuf_char(&wb, CHAR_FOR_CALL)
 694          || !writebuf_uint32(&wb, call->callid)
 695          || !writebuf_string(&wb, verb)
 696          || !writebuf_string(&wb, sessionid)
 697          || !writebuf_object(&wb, args)
 698          || !writebuf_nullstring(&wb, user_creds)) {
 699                 errno = EINVAL;
 700                 goto clean;
 701         }
 702
 703         /* send */
 704         pthread_mutex_lock(&protows->mutex);
 705         rc = afb_ws_binary_v(protows->ws, wb.iovec, wb.count);
 706         pthread_mutex_unlock(&protows->mutex);
 707         if (rc >= 0) {
 708                 rc = 0;
 709                 goto end;
 710         }
 711
 712 clean:
 713         client_call_destroy(call);
 714 end:
 715         return rc;
 716 }
 717
 718 /* get the description */
 719 int afb_proto_ws_client_describe(struct afb_proto_ws *protows, void (*callback)(void*, struct json_object*), void *closure)
 720 {
 721         struct client_describe *desc, *d;
 722         struct writebuf wb = { .count = 0 };
 723
 724         desc = malloc(sizeof *desc);
 725         if (!desc) {
 726                 errno = ENOMEM;
 727                 goto error;
 728         }
 729
 730         /* fill in stack the description of the task */
 731         pthread_mutex_lock(&protows->mutex);
 732         desc->descid = ptr2id(desc);
 733         d = protows->describes;
 734         while (d) {
 735                 if (d->descid != desc->descid)
 736                         d = d->next;
 737                 else {
 738                         desc->descid++;
 739                         d = protows->describes;
 740                 }
 741         }
 742         desc->callback = callback;
 743         desc->closure = closure;
 744         desc->protows = protows;
 745         desc->next = protows->describes;
 746         protows->describes = desc;
 747
 748         /* send */
 749         if (writebuf_char(&wb, CHAR_FOR_DESCRIBE)
 750          && writebuf_uint32(&wb, desc->descid)
 751          && afb_ws_binary_v(protows->ws, wb.iovec, wb.count) >= 0) {
 752                 pthread_mutex_unlock(&protows->mutex);
 753                 return 0;
 754         }
 755
 756         d = protows->describes;
 757         if (d == desc)
 758                 protows->describes = desc->next;
 759         else {
 760                 while(d && d->next != desc)
 761                         d = d->next;
 762                 if (d)
 763                         d->next = desc->next;
 764         }
 765         pthread_mutex_unlock(&protows->mutex);
 766         free(desc);
 767 error:
 768         /* TODO? callback(closure, NULL); */
 769         return -1;
 770 }
 771
 772 /******************* client description part for server *****************************/
 773
 774 /* on call, propagate it to the ws service */
 775 static void server_on_call(struct afb_proto_ws *protows, struct readbuf *rb)
 776 {
 777         struct afb_proto_ws_call *call;
 778         const char *uuid, *verb, *user_creds;
 779         uint32_t callid;
 780         size_t lenverb;
 781         struct json_object *object;
 782
 783         afb_proto_ws_addref(protows);
 784
 785         /* reads the call message data */
 786         if (!readbuf_uint32(rb, &callid)
 787          || !readbuf_string(rb, &verb, &lenverb)
 788          || !readbuf_string(rb, &uuid, NULL)
 789          || !readbuf_object(rb, &object)
 790          || !readbuf_nullstring(rb, &user_creds, NULL))
 791                 goto overflow;
 792
 793         /* create the request */
 794         call = malloc(sizeof *call);
 795         if (call == NULL)
 796                 goto out_of_memory;
 797
 798         call->protows = protows;
 799         call->callid = callid;
 800         call->refcount = 1;
 801         call->buffer = rb->base;
 802         rb->base = NULL; /* don't free the buffer */
 803
 804         protows->server_itf->on_call(protows->closure, call, verb, object, uuid, user_creds);
 805         return;
 806
 807 out_of_memory:
 808         json_object_put(object);
 809
 810 overflow:
 811         afb_proto_ws_unref(protows);
 812 }
 813
 814 static int server_send_description(struct afb_proto_ws *protows, uint32_t descid, struct json_object *descobj)
 815 {
 816         int rc;
 817         struct writebuf wb = { .count = 0 };
 818
 819         if (writebuf_char(&wb, CHAR_FOR_DESCRIPTION)
 820          && writebuf_uint32(&wb, descid)
 821          && writebuf_object(&wb, descobj)) {
 822                 pthread_mutex_lock(&protows->mutex);
 823                 rc = afb_ws_binary_v(protows->ws, wb.iovec, wb.count);
 824                 pthread_mutex_unlock(&protows->mutex);
 825                 if (rc >= 0)
 826                         return 0;
 827         }
 828         return -1;
 829 }
 830
 831 int afb_proto_ws_describe_put(struct afb_proto_ws_describe *describe, struct json_object *description)
 832 {
 833         int rc = server_send_description(describe->protows, describe->descid, description);
 834         afb_proto_ws_unref(describe->protows);
 835         free(describe);
 836         return rc;
 837 }
 838
 839 /* on describe, propagate it to the ws service */
 840 static void server_on_describe(struct afb_proto_ws *protows, struct readbuf *rb)
 841 {
 842         uint32_t descid;
 843         struct afb_proto_ws_describe *desc;
 844
 845         /* reads the descid */
 846         if (readbuf_uint32(rb, &descid)) {
 847                 if (protows->server_itf->on_describe) {
 848                         /* create asynchronous job */
 849                         desc = malloc(sizeof *desc);
 850                         if (desc) {
 851                                 desc->descid = descid;
 852                                 desc->protows = protows;
 853                                 afb_proto_ws_addref(protows);
 854                                 protows->server_itf->on_describe(protows->closure, desc);
 855                                 return;
 856                         }
 857                 }
 858                 server_send_description(protows, descid, NULL);
 859         }
 860 }
 861
 862 /* callback when receiving binary data */
 863 static void server_on_binary_job(int sig, void *closure)
 864 {
 865         struct binary *binary = closure;
 866
 867         if (!sig) {
 868                 switch (*binary->rb.head++) {
 869                 case CHAR_FOR_CALL:
 870                         server_on_call(binary->protows, &binary->rb);
 871                         break;
 872                 case CHAR_FOR_DESCRIBE:
 873                         server_on_describe(binary->protows, &binary->rb);
 874                         break;
 875                 default: /* unexpected message */
 876                         /* TODO: close the connection */
 877                         break;
 878                 }
 879         }
 880         free(binary->rb.base);
 881         free(binary);
 882 }
 883
 884 static void server_on_binary(void *closure, char *data, size_t size)
 885 {
 886         struct afb_proto_ws *protows = closure;
 887
 888         queue_message_processing(protows, data, size, server_on_binary_job);
 889 }
 890
 891 /******************* server part: manage events **********************************/
 892
 893 static int server_event_send(struct afb_proto_ws *protows, char order, const char *event_name, int event_id, struct json_object *data)
 894 {
 895         struct writebuf wb = { .count = 0 };
 896         int rc;
 897
 898         if (writebuf_char(&wb, order)
 899          && (order == CHAR_FOR_EVT_BROADCAST || writebuf_uint32(&wb, event_id))
 900          && writebuf_string(&wb, event_name)
 901          && (order == CHAR_FOR_EVT_ADD || order == CHAR_FOR_EVT_DEL || writebuf_object(&wb, data))) {
 902                 pthread_mutex_lock(&protows->mutex);
 903                 rc = afb_ws_binary_v(protows->ws, wb.iovec, wb.count);
 904                 pthread_mutex_unlock(&protows->mutex);
 905                 if (rc >= 0)
 906                         return 0;
 907         }
 908         return -1;
 909 }
 910
 911 int afb_proto_ws_server_event_create(struct afb_proto_ws *protows, const char *event_name, int event_id)
 912 {
 913         return server_event_send(protows, CHAR_FOR_EVT_ADD, event_name, event_id, NULL);
 914 }
 915
 916 int afb_proto_ws_server_event_remove(struct afb_proto_ws *protows, const char *event_name, int event_id)
 917 {
 918         return server_event_send(protows, CHAR_FOR_EVT_DEL, event_name, event_id, NULL);
 919 }
 920
 921 int afb_proto_ws_server_event_push(struct afb_proto_ws *protows, const char *event_name, int event_id, struct json_object *data)
 922 {
 923         return server_event_send(protows, CHAR_FOR_EVT_PUSH, event_name, event_id, data);
 924 }
 925
 926 int afb_proto_ws_server_event_broadcast(struct afb_proto_ws *protows, const char *event_name, struct json_object *data)
 927 {
 928         return server_event_send(protows, CHAR_FOR_EVT_BROADCAST, event_name, 0, data);
 929 }
 930
 931 /*****************************************************/
 932
 933 /* callback when receiving a hangup */
 934 static void on_hangup(void *closure)
 935 {
 936         struct afb_proto_ws *protows = closure;
 937         struct client_describe *cd, *ncd;
 938
 939         ncd = protows->describes;
 940         while (ncd) {
 941                 cd= ncd;
 942                 ncd = cd->next;
 943                 cd->callback(cd->closure, NULL);
 944                 free(cd);
 945         }
 946
 947         if (protows->fdev) {
 948                 fdev_unref(protows->fdev);
 949                 protows->fdev = 0;
 950                 if (protows->on_hangup)
 951                         protows->on_hangup(protows->closure);
 952         }
 953 }
 954
 955 /*****************************************************/
 956
 957 static const struct afb_ws_itf proto_ws_client_ws_itf =
 958 {
 959         .on_close = NULL,
 960         .on_text = NULL,
 961         .on_binary = client_on_binary,
 962         .on_error = NULL,
 963         .on_hangup = on_hangup
 964 };
 965
 966 static const struct afb_ws_itf server_ws_itf =
 967 {
 968         .on_close = NULL,
 969         .on_text = NULL,
 970         .on_binary = server_on_binary,
 971         .on_error = NULL,
 972         .on_hangup = on_hangup
 973 };
 974
 975 /*****************************************************/
 976
 977 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)
 978 {
 979         struct afb_proto_ws *protows;
 980
 981         protows = calloc(1, sizeof *protows);
 982         if (protows == NULL)
 983                 errno = ENOMEM;
 984         else {
 985                 fcntl(fdev_fd(fdev), F_SETFD, FD_CLOEXEC);
 986                 fcntl(fdev_fd(fdev), F_SETFL, O_NONBLOCK);
 987                 protows->ws = afb_ws_create(fdev, itf, protows);
 988                 if (protows->ws != NULL) {
 989                         protows->fdev = fdev;
 990                         protows->refcount = 1;
 991                         protows->closure = closure;
 992                         protows->server_itf = itfs;
 993                         protows->client_itf = itfc;
 994                         pthread_mutex_init(&protows->mutex, NULL);
 995                         return protows;
 996                 }
 997                 free(protows);
 998         }
 999         return NULL;
1000 }
1001
1002 struct afb_proto_ws *afb_proto_ws_create_client(struct fdev *fdev, const struct afb_proto_ws_client_itf *itf, void *closure)
1003 {
1004         return afb_proto_ws_create(fdev, NULL, itf, closure, &proto_ws_client_ws_itf);
1005 }
1006
1007 struct afb_proto_ws *afb_proto_ws_create_server(struct fdev *fdev, const struct afb_proto_ws_server_itf *itf, void *closure)
1008 {
1009         return afb_proto_ws_create(fdev, itf, NULL, closure, &server_ws_itf);
1010 }
1011
1012 void afb_proto_ws_unref(struct afb_proto_ws *protows)
1013 {
1014         if (!__atomic_sub_fetch(&protows->refcount, 1, __ATOMIC_RELAXED)) {
1015                 afb_proto_ws_hangup(protows);
1016                 afb_ws_destroy(protows->ws);
1017                 pthread_mutex_destroy(&protows->mutex);
1018                 free(protows);
1019         }
1020 }
1021
1022 void afb_proto_ws_addref(struct afb_proto_ws *protows)
1023 {
1024         __atomic_add_fetch(&protows->refcount, 1, __ATOMIC_RELAXED);
1025 }
1026
1027 int afb_proto_ws_is_client(struct afb_proto_ws *protows)
1028 {
1029         return !!protows->client_itf;
1030 }
1031
1032 int afb_proto_ws_is_server(struct afb_proto_ws *protows)
1033 {
1034         return !!protows->server_itf;
1035 }
1036
1037 void afb_proto_ws_hangup(struct afb_proto_ws *protows)
1038 {
1039         afb_ws_hangup(protows->ws);
1040 }
1041
1042 void afb_proto_ws_on_hangup(struct afb_proto_ws *protows, void (*on_hangup)(void *closure))
1043 {
1044         protows->on_hangup = on_hangup;
1045 }
1046
1047 void afb_proto_ws_set_queuing(struct afb_proto_ws *protows, int (*queuing)(void (*)(int,void*), void*))
1048 {
1049         protows->queuing = queuing;
1050 }