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 #define NO_PLUGIN_VERBOSE_MACRO
  21
  22 #include <stdlib.h>
  23 #include <string.h>
  24 #include <assert.h>
  25 #include <fcntl.h>
  26 #include <unistd.h>
  27 #include <errno.h>
  28 #include <endian.h>
  29 #include <netdb.h>
  30 #include <sys/types.h>
  31 #include <sys/socket.h>
  32 #include <sys/un.h>
  33 #include <pthread.h>
  34
  35 #include <json-c/json.h>
  36
  37 #include "afb-ws.h"
  38 #include "afb-msg-json.h"
  39 #include "afb-proto-ws.h"
  40 #include "jobs.h"
  41 #include "fdev.h"
  42
  43 struct afb_proto_ws;
  44
  45 /******** implementation of internal binder protocol per api **************/
  46 /*
  47
  48 This protocol is asymetric: there is a client and a server
  49
  50 The client can require the following actions:
  51
  52   - call a verb
  53
  54   - ask for description
  55
  56 The server must reply to the previous actions by
  57
  58   - answering success or failure of the call
  59
  60   - answering the required description
  61
  62 The server can also within the context of a call
  63
  64   - make a subcall
  65
  66   - subscribe or unsubscribe an event
  67
  68 For the purpose of handling events the server can:
  69
  70   - create/destroy an event
  71
  72   - push or brodcast data as an event
  73
  74 */
  75 /************** constants for protocol definition *************************/
  76
  77 #define CHAR_FOR_CALL             'C'
  78 #define CHAR_FOR_ANSWER_SUCCESS   'T'
  79 #define CHAR_FOR_ANSWER_FAIL      'F'
  80 #define CHAR_FOR_EVT_BROADCAST    '*'
  81 #define CHAR_FOR_EVT_ADD          '+'
  82 #define CHAR_FOR_EVT_DEL          '-'
  83 #define CHAR_FOR_EVT_PUSH         '!'
  84 #define CHAR_FOR_EVT_SUBSCRIBE    'S'
  85 #define CHAR_FOR_EVT_UNSUBSCRIBE  'U'
  86 #define CHAR_FOR_SUBCALL_CALL     'B'
  87 #define CHAR_FOR_SUBCALL_REPLY    'R'
  88 #define CHAR_FOR_DESCRIBE         'D'
  89 #define CHAR_FOR_DESCRIPTION      'd'
  90
  91 /******************* handling subcalls *****************************/
  92
  93 /**
  94  * Structure on server side for recording pending
  95  * subcalls.
  96  */
  97 struct server_subcall
  98 {
  99         struct server_subcall *next;    /**< next subcall for the client */
 100         uint32_t subcallid;             /**< the subcallid */
 101         void (*callback)(void*, int, struct json_object*); /**< callback on completion */
 102         void *closure;                  /**< closure of the callback */
 103 };
 104
 105 /**
 106  * Structure for sending back replies on client side
 107  */
 108 struct afb_proto_ws_subcall
 109 {
 110         struct afb_proto_ws *protows;   /**< proto descriptor */
 111         void *buffer;
 112         uint32_t subcallid;             /**< subcallid for the reply */
 113 };
 114
 115 /*
 116  * structure for recording calls on client side
 117  */
 118 struct client_call {
 119         struct client_call *next;       /* the next call */
 120         struct afb_proto_ws *protows;   /* the proto_ws */
 121         void *request;
 122         uint32_t callid;                /* the message identifier */
 123 };
 124
 125 /*
 126  * structure for a ws request
 127  */
 128 struct afb_proto_ws_call {
 129         struct client_call *next;       /* the next call */
 130         struct afb_proto_ws *protows;   /* the client of the request */
 131         uint32_t refcount;              /* reference count */
 132         uint32_t callid;                /* the incoming request callid */
 133         char *buffer;                   /* the incoming buffer */
 134 };
 135
 136 /*
 137  * structure for recording describe requests
 138  */
 139 struct client_describe
 140 {
 141         struct client_describe *next;
 142         struct afb_proto_ws *protows;
 143         void (*callback)(void*, struct json_object*);
 144         void *closure;
 145         uint32_t descid;
 146 };
 147
 148 /*
 149  * structure for jobs of describing
 150  */
 151 struct afb_proto_ws_describe
 152 {
 153         struct afb_proto_ws *protows;
 154         uint32_t descid;
 155 };
 156
 157 /******************* proto description for client or servers ******************/
 158
 159 struct afb_proto_ws
 160 {
 161         /* count of references */
 162         int refcount;
 163
 164         /* file descriptor */
 165         struct fdev *fdev;
 166
 167         /* resource control */
 168         pthread_mutex_t mutex;
 169
 170         /* websocket */
 171         struct afb_ws *ws;
 172
 173         /* the client closure */
 174         void *closure;
 175
 176         /* the client side interface */
 177         const struct afb_proto_ws_client_itf *client_itf;
 178
 179         /* the server side interface */
 180         const struct afb_proto_ws_server_itf *server_itf;
 181
 182         /* emitted calls (client side) */
 183         struct client_call *calls;
 184
 185         /* pending subcalls (server side) */
 186         struct server_subcall *subcalls;
 187
 188         /* pending description (client side) */
 189         struct client_describe *describes;
 190
 191         /* on hangup callback */
 192         void (*on_hangup)(void *closure);
 193 };
 194
 195 /******************* streaming objects **********************************/
 196
 197 #define WRITEBUF_COUNT_MAX  32
 198 struct writebuf
 199 {
 200         struct iovec iovec[WRITEBUF_COUNT_MAX];
 201         uint32_t uints[WRITEBUF_COUNT_MAX];
 202         int count;
 203 };
 204
 205 struct readbuf
 206 {
 207         char *base, *head, *end;
 208 };
 209
 210 struct binary
 211 {
 212         struct afb_proto_ws *protows;
 213         struct readbuf rb;
 214 };
 215
 216 /******************* common useful tools **********************************/
 217
 218 /**
 219  * translate a pointer to some integer
 220  * @param ptr the pointer to translate
 221  * @return an integer
 222  */
 223 static inline uint32_t ptr2id(void *ptr)
 224 {
 225         return (uint32_t)(((intptr_t)ptr) >> 6);
 226 }
 227
 228 /******************* serialisation part **********************************/
 229
 230 static char *readbuf_get(struct readbuf *rb, uint32_t length)
 231 {
 232         char *before = rb->head;
 233         char *after = before + length;
 234         if (after > rb->end)
 235                 return 0;
 236         rb->head = after;
 237         return before;
 238 }
 239
 240 static int readbuf_char(struct readbuf *rb, char *value)
 241 {
 242         if (rb->head >= rb->end)
 243                 return 0;
 244         *value = *rb->head++;
 245         return 1;
 246 }
 247
 248 static int readbuf_uint32(struct readbuf *rb, uint32_t *value)
 249 {
 250         char *after = rb->head + sizeof *value;
 251         if (after > rb->end)
 252                 return 0;
 253         memcpy(value, rb->head, sizeof *value);
 254         rb->head = after;
 255         *value = le32toh(*value);
 256         return 1;
 257 }
 258
 259 static int readbuf_string(struct readbuf *rb, const char **value, size_t *length)
 260 {
 261         uint32_t len;
 262         if (!readbuf_uint32(rb, &len) || !len)
 263                 return 0;
 264         if (length)
 265                 *length = (size_t)(len - 1);
 266         return (*value = readbuf_get(rb, len)) != NULL &&  rb->head[-1] == 0;
 267 }
 268
 269 static int readbuf_object(struct readbuf *rb, struct json_object **object)
 270 {
 271         const char *string;
 272         struct json_object *o;
 273         int rc = readbuf_string(rb, &string, NULL);
 274         if (rc) {
 275                 o = json_tokener_parse(string);
 276                 if (o == NULL && strcmp(string, "null"))
 277                         o = json_object_new_string(string);
 278                 *object = o;
 279         }
 280         return rc;
 281 }
 282
 283 static int writebuf_put(struct writebuf *wb, const void *value, size_t length)
 284 {
 285         int i = wb->count;
 286         if (i == WRITEBUF_COUNT_MAX)
 287                 return 0;
 288         wb->iovec[i].iov_base = (void*)value;
 289         wb->iovec[i].iov_len = length;
 290         wb->count = i + 1;
 291         return 1;
 292 }
 293
 294 static int writebuf_char(struct writebuf *wb, char value)
 295 {
 296         int i = wb->count;
 297         if (i == WRITEBUF_COUNT_MAX)
 298                 return 0;
 299         *(char*)&wb->uints[i] = value;
 300         wb->iovec[i].iov_base = &wb->uints[i];
 301         wb->iovec[i].iov_len = 1;
 302         wb->count = i + 1;
 303         return 1;
 304 }
 305
 306 static int writebuf_uint32(struct writebuf *wb, uint32_t value)
 307 {
 308         int i = wb->count;
 309         if (i == WRITEBUF_COUNT_MAX)
 310                 return 0;
 311         wb->uints[i] = htole32(value);
 312         wb->iovec[i].iov_base = &wb->uints[i];
 313         wb->iovec[i].iov_len = sizeof wb->uints[i];
 314         wb->count = i + 1;
 315         return 1;
 316 }
 317
 318 static int writebuf_string_length(struct writebuf *wb, const char *value, size_t length)
 319 {
 320         uint32_t len = (uint32_t)++length;
 321         return (size_t)len == length && len && writebuf_uint32(wb, len) && writebuf_put(wb, value, length);
 322 }
 323
 324 static int writebuf_string(struct writebuf *wb, const char *value)
 325 {
 326         return writebuf_string_length(wb, value, strlen(value));
 327 }
 328
 329 static int writebuf_object(struct writebuf *wb, struct json_object *object)
 330 {
 331         const char *string = json_object_to_json_string_ext(object, JSON_C_TO_STRING_PLAIN);
 332         return string != NULL && writebuf_string(wb, string);
 333 }
 334
 335 /******************* ws request part for server *****************/
 336
 337 void afb_proto_ws_call_addref(struct afb_proto_ws_call *call)
 338 {
 339         __atomic_add_fetch(&call->refcount, 1, __ATOMIC_RELAXED);
 340 }
 341
 342 void afb_proto_ws_call_unref(struct afb_proto_ws_call *call)
 343 {
 344         if (__atomic_sub_fetch(&call->refcount, 1, __ATOMIC_RELAXED))
 345                 return;
 346
 347         afb_proto_ws_unref(call->protows);
 348         free(call->buffer);
 349         free(call);
 350 }
 351
 352 int afb_proto_ws_call_success(struct afb_proto_ws_call *call, struct json_object *obj, const char *info)
 353 {
 354         int rc = -1;
 355         struct writebuf wb = { .count = 0 };
 356         struct afb_proto_ws *protows = call->protows;
 357
 358         if (writebuf_char(&wb, CHAR_FOR_ANSWER_SUCCESS)
 359          && writebuf_uint32(&wb, call->callid)
 360          && writebuf_string(&wb, info ?: "")
 361          && writebuf_object(&wb, obj)) {
 362                 pthread_mutex_lock(&protows->mutex);
 363                 rc = afb_ws_binary_v(protows->ws, wb.iovec, wb.count);
 364                 pthread_mutex_unlock(&protows->mutex);
 365                 if (rc >= 0) {
 366                         rc = 0;
 367                         goto success;
 368                 }
 369         }
 370 success:
 371         return rc;
 372 }
 373
 374 int afb_proto_ws_call_fail(struct afb_proto_ws_call *call, const char *status, 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_ANSWER_FAIL)
 381          && writebuf_uint32(&wb, call->callid)
 382          && writebuf_string(&wb, status)
 383          && writebuf_string(&wb, info ? : "")) {
 384                 pthread_mutex_lock(&protows->mutex);
 385                 rc = afb_ws_binary_v(protows->ws, wb.iovec, wb.count);
 386                 pthread_mutex_unlock(&protows->mutex);
 387                 if (rc >= 0) {
 388                         rc = 0;
 389                         goto success;
 390                 }
 391         }
 392 success:
 393         return rc;
 394 }
 395
 396 int afb_proto_ws_call_subcall(struct afb_proto_ws_call *call, const char *api, const char *verb, struct json_object *args, void (*callback)(void*, int, struct json_object*), void *cb_closure)
 397 {
 398         int rc = -1;
 399         struct writebuf wb = { .count = 0 };
 400         struct server_subcall *sc, *osc;
 401         struct afb_proto_ws *protows = call->protows;
 402
 403         sc = malloc(sizeof *sc);
 404         if (!sc)
 405                 errno = ENOMEM;
 406         else {
 407                 sc->callback = callback;
 408                 sc->closure = cb_closure;
 409
 410                 pthread_mutex_lock(&protows->mutex);
 411                 sc->subcallid = ptr2id(sc);
 412                 do {
 413                         sc->subcallid++;
 414                         osc = protows->subcalls;
 415                         while(osc && osc->subcallid != sc->subcallid)
 416                                 osc = osc->next;
 417                 } while (osc);
 418                 sc->next = protows->subcalls;
 419                 protows->subcalls = sc;
 420                 pthread_mutex_unlock(&protows->mutex);
 421
 422                 if (writebuf_char(&wb, CHAR_FOR_SUBCALL_CALL)
 423                  && writebuf_uint32(&wb, sc->subcallid)
 424                  && writebuf_uint32(&wb, call->callid)
 425                  && writebuf_string(&wb, api)
 426                  && writebuf_string(&wb, verb)
 427                  && writebuf_object(&wb, args)) {
 428                         pthread_mutex_lock(&protows->mutex);
 429                         rc = afb_ws_binary_v(protows->ws, wb.iovec, wb.count);
 430                         pthread_mutex_unlock(&protows->mutex);
 431                         if (rc >= 0) {
 432                                 rc = 0;
 433                                 goto success;
 434                         }
 435                 }
 436         }
 437 success:
 438         return rc;
 439 }
 440
 441 int afb_proto_ws_call_subscribe(struct afb_proto_ws_call *call, const char *event_name, int event_id)
 442 {
 443         int rc = -1;
 444         struct writebuf wb = { .count = 0 };
 445         struct afb_proto_ws *protows = call->protows;
 446
 447         if (writebuf_char(&wb, CHAR_FOR_EVT_SUBSCRIBE)
 448          && writebuf_uint32(&wb, call->callid)
 449          && writebuf_uint32(&wb, (uint32_t)event_id)
 450          && writebuf_string(&wb, event_name)) {
 451                 pthread_mutex_lock(&protows->mutex);
 452                 rc = afb_ws_binary_v(protows->ws, wb.iovec, wb.count);
 453                 pthread_mutex_unlock(&protows->mutex);
 454                 if (rc >= 0) {
 455                         rc = 0;
 456                         goto success;
 457                 }
 458         }
 459 success:
 460         return rc;
 461 }
 462
 463 int afb_proto_ws_call_unsubscribe(struct afb_proto_ws_call *call, const char *event_name, int event_id)
 464 {
 465         int rc = -1;
 466         struct writebuf wb = { .count = 0 };
 467         struct afb_proto_ws *protows = call->protows;
 468
 469         if (writebuf_char(&wb, CHAR_FOR_EVT_UNSUBSCRIBE)
 470          && writebuf_uint32(&wb, call->callid)
 471          && writebuf_uint32(&wb, (uint32_t)event_id)
 472          && writebuf_string(&wb, event_name)) {
 473                 pthread_mutex_lock(&protows->mutex);
 474                 rc = afb_ws_binary_v(protows->ws, wb.iovec, wb.count);
 475                 pthread_mutex_unlock(&protows->mutex);
 476                 if (rc >= 0) {
 477                         rc = 0;
 478                         goto success;
 479                 }
 480         }
 481 success:
 482         return rc;
 483 }
 484
 485 /******************* client part **********************************/
 486
 487 /* search a memorized call */
 488 static struct client_call *client_call_search_locked(struct afb_proto_ws *protows, uint32_t callid)
 489 {
 490         struct client_call *call;
 491
 492         call = protows->calls;
 493         while (call != NULL && call->callid != callid)
 494                 call = call->next;
 495
 496         return call;
 497 }
 498
 499 static struct client_call *client_call_search_unlocked(struct afb_proto_ws *protows, uint32_t callid)
 500 {
 501         struct client_call *result;
 502
 503         pthread_mutex_lock(&protows->mutex);
 504         result = client_call_search_locked(protows, callid);
 505         pthread_mutex_unlock(&protows->mutex);
 506         return result;
 507 }
 508
 509 /* free and release the memorizing call */
 510 static void client_call_destroy(struct client_call *call)
 511 {
 512         struct client_call **prv;
 513         struct afb_proto_ws *protows = call->protows;
 514
 515         pthread_mutex_lock(&protows->mutex);
 516         prv = &call->protows->calls;
 517         while (*prv != NULL) {
 518                 if (*prv == call) {
 519                         *prv = call->next;
 520                         break;
 521                 }
 522                 prv = &(*prv)->next;
 523         }
 524         pthread_mutex_unlock(&protows->mutex);
 525         free(call);
 526 }
 527
 528 /* get event data from the message */
 529 static int client_msg_event_read(struct readbuf *rb, uint32_t *eventid, const char **name)
 530 {
 531         return readbuf_uint32(rb, eventid) && readbuf_string(rb, name, NULL);
 532 }
 533
 534 /* get event from the message */
 535 static int client_msg_call_get(struct afb_proto_ws *protows, struct readbuf *rb, struct client_call **call)
 536 {
 537         uint32_t callid;
 538
 539         /* get event data from the message */
 540         if (!readbuf_uint32(rb, &callid)) {
 541                 return 0;
 542         }
 543
 544         /* get the call */
 545         *call = client_call_search_unlocked(protows, callid);
 546         if (*call == NULL) {
 547                 return 0;
 548         }
 549
 550         return 1;
 551 }
 552
 553 /* adds an event */
 554 static void client_on_event_create(struct afb_proto_ws *protows, struct readbuf *rb)
 555 {
 556         const char *event_name;
 557         uint32_t event_id;
 558
 559         if (protows->client_itf->on_event_create && client_msg_event_read(rb, &event_id, &event_name))
 560                 protows->client_itf->on_event_create(protows->closure, event_name, (int)event_id);
 561 }
 562
 563 /* removes an event */
 564 static void client_on_event_remove(struct afb_proto_ws *protows, struct readbuf *rb)
 565 {
 566         const char *event_name;
 567         uint32_t event_id;
 568
 569         if (protows->client_itf->on_event_remove && client_msg_event_read(rb, &event_id, &event_name))
 570                 protows->client_itf->on_event_remove(protows->closure, event_name, (int)event_id);
 571 }
 572
 573 /* subscribes an event */
 574 static void client_on_event_subscribe(struct afb_proto_ws *protows, struct readbuf *rb)
 575 {
 576         const char *event_name;
 577         uint32_t event_id;
 578         struct client_call *call;
 579
 580         if (protows->client_itf->on_event_subscribe && client_msg_call_get(protows, rb, &call) && client_msg_event_read(rb, &event_id, &event_name))
 581                 protows->client_itf->on_event_subscribe(protows->closure, call->request, event_name, (int)event_id);
 582 }
 583
 584 /* unsubscribes an event */
 585 static void client_on_event_unsubscribe(struct afb_proto_ws *protows, struct readbuf *rb)
 586 {
 587         const char *event_name;
 588         uint32_t event_id;
 589         struct client_call *call;
 590
 591         if (protows->client_itf->on_event_unsubscribe && client_msg_call_get(protows, rb, &call) && client_msg_event_read(rb, &event_id, &event_name))
 592                 protows->client_itf->on_event_unsubscribe(protows->closure, call->request, event_name, (int)event_id);
 593 }
 594
 595 /* receives broadcasted events */
 596 static void client_on_event_broadcast(struct afb_proto_ws *protows, struct readbuf *rb)
 597 {
 598         const char *event_name;
 599         struct json_object *object;
 600
 601         if (protows->client_itf->on_event_broadcast && readbuf_string(rb, &event_name, NULL) && readbuf_object(rb, &object))
 602                 protows->client_itf->on_event_broadcast(protows->closure, event_name, object);
 603 }
 604
 605 /* pushs an event */
 606 static void client_on_event_push(struct afb_proto_ws *protows, struct readbuf *rb)
 607 {
 608         const char *event_name;
 609         uint32_t event_id;
 610         struct json_object *object;
 611
 612         if (protows->client_itf->on_event_push && client_msg_event_read(rb, &event_id, &event_name) && readbuf_object(rb, &object))
 613                 protows->client_itf->on_event_push(protows->closure, event_name, (int)event_id, object);
 614 }
 615
 616 static void client_on_reply_success(struct afb_proto_ws *protows, struct readbuf *rb)
 617 {
 618         struct client_call *call;
 619         struct json_object *object;
 620         const char *info;
 621
 622         if (!client_msg_call_get(protows, rb, &call))
 623                 return;
 624
 625         if (readbuf_string(rb, &info, NULL) && readbuf_object(rb, &object)) {
 626                 protows->client_itf->on_reply_success(protows->closure, call->request, object, info);
 627         } else {
 628                 protows->client_itf->on_reply_fail(protows->closure, call->request, "proto-error", "can't process success");
 629         }
 630         client_call_destroy(call);
 631 }
 632
 633 static void client_on_reply_fail(struct afb_proto_ws *protows, struct readbuf *rb)
 634 {
 635         struct client_call *call;
 636         const char *info, *status;
 637
 638         if (!client_msg_call_get(protows, rb, &call))
 639                 return;
 640
 641
 642         if (readbuf_string(rb, &status, NULL) && readbuf_string(rb, &info, NULL)) {
 643                 protows->client_itf->on_reply_fail(protows->closure, call->request, status, info);
 644         } else {
 645                 protows->client_itf->on_reply_fail(protows->closure, call->request, "proto-error", "can't process fail");
 646         }
 647         client_call_destroy(call);
 648 }
 649
 650 /* send a subcall reply */
 651 static int client_send_subcall_reply(struct afb_proto_ws *protows, uint32_t subcallid, int status, json_object *object)
 652 {
 653         struct writebuf wb = { .count = 0 };
 654         char ie = status < 0;
 655         int rc;
 656
 657         if (writebuf_char(&wb, CHAR_FOR_SUBCALL_REPLY)
 658          && writebuf_uint32(&wb, subcallid)
 659          && writebuf_char(&wb, ie)
 660          && writebuf_object(&wb, object)) {
 661                 pthread_mutex_lock(&protows->mutex);
 662                 rc = afb_ws_binary_v(protows->ws, wb.iovec, wb.count);
 663                 pthread_mutex_unlock(&protows->mutex);
 664                 if (rc >= 0)
 665                         return 0;
 666         }
 667         return -1;
 668 }
 669
 670 /* callback for subcall reply */
 671 int afb_proto_ws_subcall_reply(struct afb_proto_ws_subcall *subcall, int status, struct json_object *result)
 672 {
 673         int rc = client_send_subcall_reply(subcall->protows, subcall->subcallid, status, result);
 674         afb_proto_ws_unref(subcall->protows);
 675         free(subcall->buffer);
 676         free(subcall);
 677         return rc;
 678 }
 679
 680 /* received a subcall request */
 681 static void client_on_subcall(struct afb_proto_ws *protows, struct readbuf *rb)
 682 {
 683         struct afb_proto_ws_subcall *subcall;
 684         struct client_call *call;
 685         const char *api, *verb;
 686         uint32_t subcallid;
 687         struct json_object *object;
 688
 689         /* get the subcallid */
 690         if (!readbuf_uint32(rb, &subcallid))
 691                 return;
 692
 693         /* if not expected drop it */
 694         if (!protows->client_itf->on_subcall)
 695                 goto error;
 696
 697         /* retrieve the message data */
 698         if (!client_msg_call_get(protows, rb, &call))
 699                 goto error;
 700
 701         /* allocation of the subcall */
 702         subcall = malloc(sizeof *subcall);
 703         if (!subcall)
 704                 goto error;
 705
 706         /* make the call */
 707         if (readbuf_string(rb, &api, NULL)
 708          && readbuf_string(rb, &verb, NULL)
 709          && readbuf_object(rb, &object)) {
 710                 afb_proto_ws_addref(protows);
 711                 subcall->protows = protows;
 712                 subcall->subcallid = subcallid;
 713                 subcall->buffer = rb->base;
 714                 rb->base = NULL;
 715                 protows->client_itf->on_subcall(protows->closure, subcall, call->request, api, verb, object);
 716                 return;
 717         }
 718         free(subcall);
 719 error:
 720         client_send_subcall_reply(protows, subcallid, 1, NULL);
 721 }
 722
 723 static void client_on_description(struct afb_proto_ws *protows, struct readbuf *rb)
 724 {
 725         uint32_t descid;
 726         struct client_describe *desc, **prv;
 727         struct json_object *object;
 728
 729         if (readbuf_uint32(rb, &descid)) {
 730                 pthread_mutex_lock(&protows->mutex);
 731                 prv = &protows->describes;
 732                 while ((desc = *prv) && desc->descid != descid)
 733                         prv = &desc->next;
 734                 if (!desc)
 735                         pthread_mutex_unlock(&protows->mutex);
 736                 else {
 737                         *prv = desc->next;
 738                         pthread_mutex_unlock(&protows->mutex);
 739                         if (!readbuf_object(rb, &object))
 740                                 object = NULL;
 741                         desc->callback(desc->closure, object);
 742                         free(desc);
 743                 }
 744         }
 745 }
 746
 747 /* callback when receiving binary data */
 748 static void client_on_binary_job(int sig, void *closure)
 749 {
 750         struct binary *binary = closure;
 751
 752         if (!sig) {
 753                 switch (*binary->rb.head++) {
 754                 case CHAR_FOR_ANSWER_SUCCESS: /* success */
 755                         client_on_reply_success(binary->protows, &binary->rb);
 756                         break;
 757                 case CHAR_FOR_ANSWER_FAIL: /* fail */
 758                         client_on_reply_fail(binary->protows, &binary->rb);
 759                         break;
 760                 case CHAR_FOR_EVT_BROADCAST: /* broadcast */
 761                         client_on_event_broadcast(binary->protows, &binary->rb);
 762                         break;
 763                 case CHAR_FOR_EVT_ADD: /* creates the event */
 764                         client_on_event_create(binary->protows, &binary->rb);
 765                         break;
 766                 case CHAR_FOR_EVT_DEL: /* removes the event */
 767                         client_on_event_remove(binary->protows, &binary->rb);
 768                         break;
 769                 case CHAR_FOR_EVT_PUSH: /* pushs the event */
 770                         client_on_event_push(binary->protows, &binary->rb);
 771                         break;
 772                 case CHAR_FOR_EVT_SUBSCRIBE: /* subscribe event for a request */
 773                         client_on_event_subscribe(binary->protows, &binary->rb);
 774                         break;
 775                 case CHAR_FOR_EVT_UNSUBSCRIBE: /* unsubscribe event for a request */
 776                         client_on_event_unsubscribe(binary->protows, &binary->rb);
 777                         break;
 778                 case CHAR_FOR_SUBCALL_CALL: /* subcall */
 779                         client_on_subcall(binary->protows, &binary->rb);
 780                         break;
 781                 case CHAR_FOR_DESCRIPTION: /* description */
 782                         client_on_description(binary->protows, &binary->rb);
 783                         break;
 784                 default: /* unexpected message */
 785                         /* TODO: close the connection */
 786                         break;
 787                 }
 788         }
 789         free(binary->rb.base);
 790         free(binary);
 791 }
 792
 793 /* callback when receiving binary data */
 794 static void client_on_binary(void *closure, char *data, size_t size)
 795 {
 796         int rc;
 797         struct binary *binary;
 798
 799         if (size) {
 800                 binary = malloc(sizeof *binary);
 801                 if (!binary) {
 802                         errno = ENOMEM;
 803                 } else {
 804                         binary->protows = closure;
 805                         binary->rb.base = data;
 806                         binary->rb.head = data;
 807                         binary->rb.end = data + size;
 808                         rc = jobs_queue(NULL, 0, client_on_binary_job, binary);
 809                         if (rc >= 0)
 810                                 return;
 811                         free(binary);
 812                 }
 813         }
 814         free(data);
 815 }
 816
 817 int afb_proto_ws_client_call(
 818                 struct afb_proto_ws *protows,
 819                 const char *verb,
 820                 struct json_object *args,
 821                 const char *sessionid,
 822                 void *request
 823 )
 824 {
 825         int rc = -1;
 826         struct client_call *call;
 827         struct writebuf wb = { .count = 0 };
 828
 829         /* allocate call data */
 830         call = malloc(sizeof *call);
 831         if (call == NULL) {
 832                 errno = ENOMEM;
 833                 return -1;
 834         }
 835         call->request = request;
 836
 837         /* init call data */
 838         pthread_mutex_lock(&protows->mutex);
 839         call->callid = ptr2id(call);
 840         while(client_call_search_locked(protows, call->callid) != NULL)
 841                 call->callid++;
 842         call->protows = protows;
 843         call->next = protows->calls;
 844         protows->calls = call;
 845         pthread_mutex_unlock(&protows->mutex);
 846
 847         /* creates the call message */
 848         if (!writebuf_char(&wb, CHAR_FOR_CALL)
 849          || !writebuf_uint32(&wb, call->callid)
 850          || !writebuf_string(&wb, verb)
 851          || !writebuf_string(&wb, sessionid)
 852          || !writebuf_object(&wb, args)) {
 853                 errno = EINVAL;
 854                 goto clean;
 855         }
 856
 857         /* send */
 858         pthread_mutex_lock(&protows->mutex);
 859         rc = afb_ws_binary_v(protows->ws, wb.iovec, wb.count);
 860         pthread_mutex_unlock(&protows->mutex);
 861         if (rc >= 0) {
 862                 rc = 0;
 863                 goto end;
 864         }
 865
 866 clean:
 867         client_call_destroy(call);
 868 end:
 869         return rc;
 870 }
 871
 872 /* get the description */
 873 int afb_proto_ws_client_describe(struct afb_proto_ws *protows, void (*callback)(void*, struct json_object*), void *closure)
 874 {
 875         struct client_describe *desc, *d;
 876         struct writebuf wb = { .count = 0 };
 877
 878         desc = malloc(sizeof *desc);
 879         if (!desc) {
 880                 errno = ENOMEM;
 881                 goto error;
 882         }
 883
 884         /* fill in stack the description of the task */
 885         pthread_mutex_lock(&protows->mutex);
 886         desc->descid = ptr2id(desc);
 887         d = protows->describes;
 888         while (d) {
 889                 if (d->descid != desc->descid)
 890                         d = d->next;
 891                 else {
 892                         desc->descid++;
 893                         d = protows->describes;
 894                 }
 895         }
 896         desc->callback = callback;
 897         desc->closure = closure;
 898         desc->protows = protows;
 899         desc->next = protows->describes;
 900         protows->describes = desc;
 901
 902         /* send */
 903         if (writebuf_char(&wb, CHAR_FOR_DESCRIBE)
 904          && writebuf_uint32(&wb, desc->descid)
 905          && afb_ws_binary_v(protows->ws, wb.iovec, wb.count) >= 0) {
 906                 pthread_mutex_unlock(&protows->mutex);
 907                 return 0;
 908         }
 909
 910         d = protows->describes;
 911         if (d == desc)
 912                 protows->describes = desc->next;
 913         else {
 914                 while(d && d->next != desc)
 915                         d = d->next;
 916                 if (d)
 917                         d->next = desc->next;
 918         }
 919         pthread_mutex_unlock(&protows->mutex);
 920         free(desc);
 921 error:
 922         /* TODO? callback(closure, NULL); */
 923         return -1;
 924 }
 925
 926 /******************* client description part for server *****************************/
 927
 928 /* on call, propagate it to the ws service */
 929 static void server_on_call(struct afb_proto_ws *protows, struct readbuf *rb)
 930 {
 931         struct afb_proto_ws_call *call;
 932         const char *uuid, *verb;
 933         uint32_t callid;
 934         size_t lenverb;
 935         struct json_object *object;
 936
 937         afb_proto_ws_addref(protows);
 938
 939         /* reads the call message data */
 940         if (!readbuf_uint32(rb, &callid)
 941          || !readbuf_string(rb, &verb, &lenverb)
 942          || !readbuf_string(rb, &uuid, NULL)
 943          || !readbuf_object(rb, &object))
 944                 goto overflow;
 945
 946         /* create the request */
 947         call = malloc(sizeof *call);
 948         if (call == NULL)
 949                 goto out_of_memory;
 950
 951         call->protows = protows;
 952         call->callid = callid;
 953         call->refcount = 1;
 954         call->buffer = rb->base;
 955         rb->base = NULL; /* don't free the buffer */
 956
 957         protows->server_itf->on_call(protows->closure, call, verb, object, uuid);
 958         return;
 959
 960 out_of_memory:
 961         json_object_put(object);
 962
 963 overflow:
 964         afb_proto_ws_unref(protows);
 965 }
 966
 967 /* on subcall reply */
 968 static void server_on_subcall_reply(struct afb_proto_ws *protows, struct readbuf *rb)
 969 {
 970         char ie;
 971         uint32_t subcallid;
 972         struct json_object *object;
 973         struct server_subcall *sc, **psc;
 974
 975         /* reads the call message data */
 976         if (!readbuf_uint32(rb, &subcallid)
 977          || !readbuf_char(rb, &ie)
 978          || !readbuf_object(rb, &object)) {
 979                 /* TODO bad protocol */
 980                 return;
 981         }
 982
 983         /* search the subcall and unlink it */
 984         pthread_mutex_lock(&protows->mutex);
 985         psc = &protows->subcalls;
 986         while ((sc = *psc) && sc->subcallid != subcallid)
 987                 psc = &sc->next;
 988         if (!sc) {
 989                 pthread_mutex_unlock(&protows->mutex);
 990                 json_object_put(object);
 991                 /* TODO subcall not found */
 992         } else {
 993                 *psc = sc->next;
 994                 pthread_mutex_unlock(&protows->mutex);
 995                 sc->callback(sc->closure, -(int)ie, object);
 996                 free(sc);
 997         }
 998 }
 999
1000 static int server_send_description(struct afb_proto_ws *protows, uint32_t descid, struct json_object *descobj)
1001 {
1002         int rc;
1003         struct writebuf wb = { .count = 0 };
1004
1005         if (writebuf_char(&wb, CHAR_FOR_DESCRIPTION)
1006          && writebuf_uint32(&wb, descid)
1007          && writebuf_object(&wb, descobj)) {
1008                 pthread_mutex_lock(&protows->mutex);
1009                 rc = afb_ws_binary_v(protows->ws, wb.iovec, wb.count);
1010                 pthread_mutex_unlock(&protows->mutex);
1011                 if (rc >= 0)
1012                         return 0;
1013         }
1014         return -1;
1015 }
1016
1017 int afb_proto_ws_describe_put(struct afb_proto_ws_describe *describe, struct json_object *description)
1018 {
1019         int rc = server_send_description(describe->protows, describe->descid, description);
1020         afb_proto_ws_unref(describe->protows);
1021         free(describe);
1022         return rc;
1023 }
1024
1025 /* on describe, propagate it to the ws service */
1026 static void server_on_describe(struct afb_proto_ws *protows, struct readbuf *rb)
1027 {
1028         uint32_t descid;
1029         struct afb_proto_ws_describe *desc;
1030
1031         /* reads the descid */
1032         if (readbuf_uint32(rb, &descid)) {
1033                 if (protows->server_itf->on_describe) {
1034                         /* create asynchronous job */
1035                         desc = malloc(sizeof *desc);
1036                         if (desc) {
1037                                 desc->descid = descid;
1038                                 desc->protows = protows;
1039                                 afb_proto_ws_addref(protows);
1040                                 protows->server_itf->on_describe(protows->closure, desc);
1041                                 return;
1042                         }
1043                 }
1044                 server_send_description(protows, descid, NULL);
1045         }
1046 }
1047
1048 /* callback when receiving binary data */
1049 static void server_on_binary_job(int sig, void *closure)
1050 {
1051         struct binary *binary = closure;
1052
1053         if (!sig) {
1054                 switch (*binary->rb.head++) {
1055                 case CHAR_FOR_CALL:
1056                         server_on_call(binary->protows, &binary->rb);
1057                         break;
1058                 case CHAR_FOR_SUBCALL_REPLY:
1059                         server_on_subcall_reply(binary->protows, &binary->rb);
1060                         break;
1061                 case CHAR_FOR_DESCRIBE:
1062                         server_on_describe(binary->protows, &binary->rb);
1063                         break;
1064                 default: /* unexpected message */
1065                         /* TODO: close the connection */
1066                         break;
1067                 }
1068         }
1069         free(binary->rb.base);
1070         free(binary);
1071 }
1072
1073 static void server_on_binary(void *closure, char *data, size_t size)
1074 {
1075         int rc;
1076         struct binary *binary;
1077
1078         if (size) {
1079                 binary = malloc(sizeof *binary);
1080                 if (!binary) {
1081                         errno = ENOMEM;
1082                 } else {
1083                         binary->protows = closure;
1084                         binary->rb.base = data;
1085                         binary->rb.head = data;
1086                         binary->rb.end = data + size;
1087                         rc = jobs_queue(NULL, 0, server_on_binary_job, binary);
1088                         if (rc >= 0)
1089                                 return;
1090                         free(binary);
1091                 }
1092         }
1093         free(data);
1094 }
1095
1096 /******************* server part: manage events **********************************/
1097
1098 static int server_event_send(struct afb_proto_ws *protows, char order, const char *event_name, int event_id, struct json_object *data)
1099 {
1100         struct writebuf wb = { .count = 0 };
1101         int rc;
1102
1103         if (writebuf_char(&wb, order)
1104          && (order == CHAR_FOR_EVT_BROADCAST || writebuf_uint32(&wb, event_id))
1105          && writebuf_string(&wb, event_name)
1106          && (order == CHAR_FOR_EVT_ADD || order == CHAR_FOR_EVT_DEL || writebuf_object(&wb, data))) {
1107                 pthread_mutex_lock(&protows->mutex);
1108                 rc = afb_ws_binary_v(protows->ws, wb.iovec, wb.count);
1109                 pthread_mutex_unlock(&protows->mutex);
1110                 if (rc >= 0)
1111                         return 0;
1112         }
1113         return -1;
1114 }
1115
1116 int afb_proto_ws_server_event_create(struct afb_proto_ws *protows, const char *event_name, int event_id)
1117 {
1118         return server_event_send(protows, CHAR_FOR_EVT_ADD, event_name, event_id, NULL);
1119 }
1120
1121 int afb_proto_ws_server_event_remove(struct afb_proto_ws *protows, const char *event_name, int event_id)
1122 {
1123         return server_event_send(protows, CHAR_FOR_EVT_DEL, event_name, event_id, NULL);
1124 }
1125
1126 int afb_proto_ws_server_event_push(struct afb_proto_ws *protows, const char *event_name, int event_id, struct json_object *data)
1127 {
1128         return server_event_send(protows, CHAR_FOR_EVT_PUSH, event_name, event_id, data);
1129 }
1130
1131 int afb_proto_ws_server_event_broadcast(struct afb_proto_ws *protows, const char *event_name, struct json_object *data)
1132 {
1133         return server_event_send(protows, CHAR_FOR_EVT_BROADCAST, event_name, 0, data);
1134 }
1135
1136 /*****************************************************/
1137
1138 /* callback when receiving a hangup */
1139 static void on_hangup(void *closure)
1140 {
1141         struct afb_proto_ws *protows = closure;
1142         struct server_subcall *sc, *nsc;
1143         struct client_describe *cd, *ncd;
1144
1145         nsc = protows->subcalls;
1146         while (nsc) {
1147                 sc= nsc;
1148                 nsc = sc->next;
1149                 sc->callback(sc->closure, 1, NULL);
1150                 free(sc);
1151         }
1152
1153         ncd = protows->describes;
1154         while (ncd) {
1155                 cd= ncd;
1156                 ncd = cd->next;
1157                 cd->callback(cd->closure, NULL);
1158                 free(cd);
1159         }
1160
1161         if (protows->fdev) {
1162                 fdev_unref(protows->fdev);
1163                 protows->fdev = 0;
1164                 if (protows->on_hangup)
1165                         protows->on_hangup(protows->closure);
1166         }
1167 }
1168
1169 /*****************************************************/
1170
1171 static const struct afb_ws_itf proto_ws_client_ws_itf =
1172 {
1173         .on_close = NULL,
1174         .on_text = NULL,
1175         .on_binary = client_on_binary,
1176         .on_error = NULL,
1177         .on_hangup = on_hangup
1178 };
1179
1180 static const struct afb_ws_itf server_ws_itf =
1181 {
1182         .on_close = NULL,
1183         .on_text = NULL,
1184         .on_binary = server_on_binary,
1185         .on_error = NULL,
1186         .on_hangup = on_hangup
1187 };
1188
1189 /*****************************************************/
1190
1191 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)
1192 {
1193         struct afb_proto_ws *protows;
1194
1195         protows = calloc(1, sizeof *protows);
1196         if (protows == NULL)
1197                 errno = ENOMEM;
1198         else {
1199                 fcntl(fdev_fd(fdev), F_SETFD, FD_CLOEXEC);
1200                 fcntl(fdev_fd(fdev), F_SETFL, O_NONBLOCK);
1201                 protows->ws = afb_ws_create(fdev, itf, protows);
1202                 if (protows->ws != NULL) {
1203                         protows->fdev = fdev;
1204                         protows->refcount = 1;
1205                         protows->subcalls = NULL;
1206                         protows->closure = closure;
1207                         protows->server_itf = itfs;
1208                         protows->client_itf = itfc;
1209                         pthread_mutex_init(&protows->mutex, NULL);
1210                         return protows;
1211                 }
1212                 free(protows);
1213         }
1214         return NULL;
1215 }
1216
1217 struct afb_proto_ws *afb_proto_ws_create_client(struct fdev *fdev, const struct afb_proto_ws_client_itf *itf, void *closure)
1218 {
1219         return afb_proto_ws_create(fdev, NULL, itf, closure, &proto_ws_client_ws_itf);
1220 }
1221
1222 struct afb_proto_ws *afb_proto_ws_create_server(struct fdev *fdev, const struct afb_proto_ws_server_itf *itf, void *closure)
1223 {
1224         return afb_proto_ws_create(fdev, itf, NULL, closure, &server_ws_itf);
1225 }
1226
1227 void afb_proto_ws_unref(struct afb_proto_ws *protows)
1228 {
1229         if (!__atomic_sub_fetch(&protows->refcount, 1, __ATOMIC_RELAXED)) {
1230                 afb_proto_ws_hangup(protows);
1231                 afb_ws_destroy(protows->ws);
1232                 pthread_mutex_destroy(&protows->mutex);
1233                 free(protows);
1234         }
1235 }
1236
1237 void afb_proto_ws_addref(struct afb_proto_ws *protows)
1238 {
1239         __atomic_add_fetch(&protows->refcount, 1, __ATOMIC_RELAXED);
1240 }
1241
1242 int afb_proto_ws_is_client(struct afb_proto_ws *protows)
1243 {
1244         return !!protows->client_itf;
1245 }
1246
1247 int afb_proto_ws_is_server(struct afb_proto_ws *protows)
1248 {
1249         return !!protows->server_itf;
1250 }
1251
1252 void afb_proto_ws_hangup(struct afb_proto_ws *protows)
1253 {
1254         afb_ws_hangup(protows->ws);
1255 }
1256
1257 void afb_proto_ws_on_hangup(struct afb_proto_ws *protows, void (*on_hangup)(void *closure))
1258 {
1259         protows->on_hangup = on_hangup;
1260 }
1261