src/afb-proto-ws.c

   1 /*
   2  * Copyright (C) 2015, 2016, 2017 "IoT.bzh"
   3  * Author José Bollo <jose.bollo@iot.bzh>
   4  *
   5  * Licensed under the Apache License, Version 2.0 (the "License");
   6  * you may not use this file except in compliance with the License.
   7  * You may obtain a copy of the License at
   8  *
   9  *   http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  * Unless required by applicable law or agreed to in writing, software
  12  * distributed under the License is distributed on an "AS IS" BASIS,
  13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14  * See the License for the specific language governing permissions and
  15  * limitations under the License.
  16  */
  17
  18 #define _GNU_SOURCE
  19
  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
  42 struct afb_proto_ws;
  43
  44 /******** implementation of internal binder protocol per api **************/
  45 /*
  46
  47 This protocol is asymetric: there is a client and a server
  48
  49 The client can require the following actions:
  50
  51   - call a verb
  52
  53   - ask for description
  54
  55 The server must reply to the previous actions by
  56
  57   - answering success or failure of the call
  58
  59   - answering the required description
  60
  61 The server can also within the context of a call
  62
  63   - make a subcall
  64
  65   - subscribe or unsubscribe an event
  66
  67 For the purpose of handling events the server can:
  68
  69   - create/destroy an event
  70
  71   - push or brodcast data as an event
  72
  73 */
  74 /************** constants for protocol definition *************************/
  75
  76 #define CHAR_FOR_CALL             'C'
  77 #define CHAR_FOR_ANSWER_SUCCESS   'T'
  78 #define CHAR_FOR_ANSWER_FAIL      'F'
  79 #define CHAR_FOR_EVT_BROADCAST    '*'
  80 #define CHAR_FOR_EVT_ADD          '+'
  81 #define CHAR_FOR_EVT_DEL          '-'
  82 #define CHAR_FOR_EVT_PUSH         '!'
  83 #define CHAR_FOR_EVT_SUBSCRIBE    'S'
  84 #define CHAR_FOR_EVT_UNSUBSCRIBE  'U'
  85 #define CHAR_FOR_SUBCALL_CALL     'B'
  86 #define CHAR_FOR_SUBCALL_REPLY    'R'
  87 #define CHAR_FOR_DESCRIBE         'D'
  88 #define CHAR_FOR_DESCRIPTION      'd'
  89
  90 /******************* handling subcalls *****************************/
  91
  92 /**
  93  * Structure on server side for recording pending
  94  * subcalls.
  95  */
  96 struct server_subcall
  97 {
  98         struct server_subcall *next;    /**< next subcall for the client */
  99         uint32_t subcallid;             /**< the subcallid */
 100         void (*callback)(void*, int, struct json_object*); /**< callback on completion */
 101         void *closure;                  /**< closure of the callback */
 102 };
 103
 104 /**
 105  * Structure for sending back replies on client side
 106  */
 107 struct afb_proto_ws_subcall
 108 {
 109         struct afb_proto_ws *protows;   /**< proto descriptor */
 110         void *buffer;
 111         uint32_t subcallid;             /**< subcallid for the reply */
 112 };
 113
 114 /*
 115  * structure for recording calls on client side
 116  */
 117 struct client_call {
 118         struct client_call *next;       /* the next call */
 119         struct afb_proto_ws *protows;   /* the proto_ws */
 120         void *request;
 121         uint32_t callid;                /* the message identifier */
 122 };
 123
 124 /*
 125  * structure for a ws request
 126  */
 127 struct afb_proto_ws_call {
 128         struct client_call *next;       /* the next call */
 129         struct afb_proto_ws *protows;   /* the client of the request */
 130         uint32_t refcount;              /* reference count */
 131         uint32_t callid;                /* the incoming request callid */
 132         char *buffer;                   /* the incoming buffer */
 133 };
 134
 135 /*
 136  * structure for recording describe requests
 137  */
 138 struct client_describe
 139 {
 140         struct client_describe *next;
 141         struct afb_proto_ws *protows;
 142         void (*callback)(void*, struct json_object*);
 143         void *closure;
 144         uint32_t descid;
 145 };
 146
 147 /*
 148  * structure for jobs of describing
 149  */
 150 struct afb_proto_ws_describe
 151 {
 152         struct afb_proto_ws *protows;
 153         uint32_t descid;
 154 };
 155
 156 /******************* proto description for client or servers ******************/
 157
 158 struct afb_proto_ws
 159 {
 160         /* count of references */
 161         int refcount;
 162
 163         /* file descriptor */
 164         int fd;
 165
 166         /* resource control */
 167         pthread_mutex_t mutex;
 168
 169         /* websocket */
 170         struct afb_ws *ws;
 171
 172         /* the client closure */
 173         void *closure;
 174
 175         /* the client side interface */
 176         const struct afb_proto_ws_client_itf *client_itf;
 177
 178         /* the server side interface */
 179         const struct afb_proto_ws_server_itf *server_itf;
 180
 181         /* emitted calls (client side) */
 182         struct client_call *calls;
 183
 184         /* pending subcalls (server side) */
 185         struct server_subcall *subcalls;
 186
 187         /* pending description (client side) */
 188         struct client_describe *describes;
 189
 190         /* on hangup callback */
 191         void (*on_hangup)(void *closure);
 192 };
 193
 194 /******************* streaming objects **********************************/
 195
 196 #define WRITEBUF_COUNT_MAX  32
 197 struct writebuf
 198 {
 199         struct iovec iovec[WRITEBUF_COUNT_MAX];
 200         uint32_t uints[WRITEBUF_COUNT_MAX];
 201         int count;
 202 };
 203
 204 struct readbuf
 205 {
 206         char *base, *head, *end;
 207 };
 208
 209 struct binary
 210 {
 211         struct afb_proto_ws *protows;
 212         struct readbuf rb;
 213 };
 214
 215 /******************* common useful tools **********************************/
 216
 217 /**
 218  * translate a pointer to some integer
 219  * @param ptr the pointer to translate
 220  * @return an integer
 221  */
 222 static inline uint32_t ptr2id(void *ptr)
 223 {
 224         return (uint32_t)(((intptr_t)ptr) >> 6);
 225 }
 226
 227 /******************* serialisation part **********************************/
 228
 229 static char *readbuf_get(struct readbuf *rb, uint32_t length)
 230 {
 231         char *before = rb->head;
 232         char *after = before + length;
 233         if (after > rb->end)
 234                 return 0;
 235         rb->head = after;
 236         return before;
 237 }
 238
 239 static int readbuf_char(struct readbuf *rb, char *value)
 240 {
 241         if (rb->head >= rb->end)
 242                 return 0;
 243         *value = *rb->head++;
 244         return 1;
 245 }
 246
 247 static int readbuf_uint32(struct readbuf *rb, uint32_t *value)
 248 {
 249         char *after = rb->head + sizeof *value;
 250         if (after > rb->end)
 251                 return 0;
 252         memcpy(value, rb->head, sizeof *value);
 253         rb->head = after;
 254         *value = le32toh(*value);
 255         return 1;
 256 }
 257
 258 static int readbuf_string(struct readbuf *rb, const char **value, size_t *length)
 259 {
 260         uint32_t len;
 261         if (!readbuf_uint32(rb, &len) || !len)
 262                 return 0;
 263         if (length)
 264                 *length = (size_t)(len - 1);
 265         return (*value = readbuf_get(rb, len)) != NULL &&  rb->head[-1] == 0;
 266 }
 267
 268 static int readbuf_object(struct readbuf *rb, struct json_object **object)
 269 {
 270         const char *string;
 271         struct json_object *o;
 272         int rc = readbuf_string(rb, &string, NULL);
 273         if (rc) {
 274                 o = json_tokener_parse(string);
 275                 if (o == NULL && strcmp(string, "null"))
 276                         o = json_object_new_string(string);
 277                 *object = o;
 278         }
 279         return rc;
 280 }
 281
 282 static int writebuf_put(struct writebuf *wb, const void *value, size_t length)
 283 {
 284         int i = wb->count;
 285         if (i == WRITEBUF_COUNT_MAX)
 286                 return 0;
 287         wb->iovec[i].iov_base = (void*)value;
 288         wb->iovec[i].iov_len = length;
 289         wb->count = i + 1;
 290         return 1;
 291 }
 292
 293 static int writebuf_char(struct writebuf *wb, char value)
 294 {
 295         int i = wb->count;
 296         if (i == WRITEBUF_COUNT_MAX)
 297                 return 0;
 298         *(char*)&wb->uints[i] = value;
 299         wb->iovec[i].iov_base = &wb->uints[i];
 300         wb->iovec[i].iov_len = 1;
 301         wb->count = i + 1;
 302         return 1;
 303 }
 304
 305 static int writebuf_uint32(struct writebuf *wb, uint32_t value)
 306 {
 307         int i = wb->count;
 308         if (i == WRITEBUF_COUNT_MAX)
 309                 return 0;
 310         wb->uints[i] = htole32(value);
 311         wb->iovec[i].iov_base = &wb->uints[i];
 312         wb->iovec[i].iov_len = sizeof wb->uints[i];
 313         wb->count = i + 1;
 314         return 1;
 315 }
 316
 317 static int writebuf_string_length(struct writebuf *wb, const char *value, size_t length)
 318 {
 319         uint32_t len = (uint32_t)++length;
 320         return (size_t)len == length && len && writebuf_uint32(wb, len) && writebuf_put(wb, value, length);
 321 }
 322
 323 static int writebuf_string(struct writebuf *wb, const char *value)
 324 {
 325         return writebuf_string_length(wb, value, strlen(value));
 326 }
 327
 328 static int writebuf_object(struct writebuf *wb, struct json_object *object)
 329 {
 330         const char *string = json_object_to_json_string_ext(object, JSON_C_TO_STRING_PLAIN);
 331         return string != NULL && writebuf_string(wb, string);
 332 }
 333
 334 /******************* ws request part for server *****************/
 335
 336 void afb_proto_ws_call_addref(struct afb_proto_ws_call *call)
 337 {
 338         __atomic_add_fetch(&call->refcount, 1, __ATOMIC_RELAXED);
 339 }
 340
 341 void afb_proto_ws_call_unref(struct afb_proto_ws_call *call)
 342 {
 343         if (__atomic_sub_fetch(&call->refcount, 1, __ATOMIC_RELAXED))
 344                 return;
 345
 346         afb_proto_ws_unref(call->protows);
 347         free(call->buffer);
 348         free(call);
 349 }
 350
 351 int afb_proto_ws_call_success(struct afb_proto_ws_call *call, struct json_object *obj, const char *info)
 352 {
 353         int rc = -1;
 354         struct writebuf wb = { .count = 0 };
 355         struct afb_proto_ws *protows = call->protows;
 356
 357         if (writebuf_char(&wb, CHAR_FOR_ANSWER_SUCCESS)
 358          && writebuf_uint32(&wb, call->callid)
 359          && writebuf_string(&wb, info ?: "")
 360          && writebuf_object(&wb, obj)) {
 361                 pthread_mutex_lock(&protows->mutex);
 362                 rc = afb_ws_binary_v(protows->ws, wb.iovec, wb.count);
 363                 pthread_mutex_unlock(&protows->mutex);
 364                 if (rc >= 0) {
 365                         rc = 0;
 366                         goto success;
 367                 }
 368         }
 369 success:
 370         return rc;
 371 }
 372
 373 int afb_proto_ws_call_fail(struct afb_proto_ws_call *call, const char *status, const char *info)
 374 {
 375         int rc = -1;
 376         struct writebuf wb = { .count = 0 };
 377         struct afb_proto_ws *protows = call->protows;
 378
 379         if (writebuf_char(&wb, CHAR_FOR_ANSWER_FAIL)
 380          && writebuf_uint32(&wb, call->callid)
 381          && writebuf_string(&wb, status)
 382          && writebuf_string(&wb, info ? : "")) {
 383                 pthread_mutex_lock(&protows->mutex);
 384                 rc = afb_ws_binary_v(protows->ws, wb.iovec, wb.count);
 385                 pthread_mutex_unlock(&protows->mutex);
 386                 if (rc >= 0) {
 387                         rc = 0;
 388                         goto success;
 389                 }
 390         }
 391 success:
 392         return rc;
 393 }
 394
 395 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)
 396 {
 397         int rc = -1;
 398         struct writebuf wb = { .count = 0 };
 399         struct server_subcall *sc, *osc;
 400         struct afb_proto_ws *protows = call->protows;
 401
 402         sc = malloc(sizeof *sc);
 403         if (!sc)
 404                 errno = ENOMEM;
 405         else {
 406                 sc->callback = callback;
 407                 sc->closure = cb_closure;
 408
 409                 pthread_mutex_lock(&protows->mutex);
 410                 sc->subcallid = ptr2id(sc);
 411                 do {
 412                         sc->subcallid++;
 413                         osc = protows->subcalls;
 414                         while(osc && osc->subcallid != sc->subcallid)
 415                                 osc = osc->next;
 416                 } while (osc);
 417                 sc->next = protows->subcalls;
 418                 protows->subcalls = sc;
 419                 pthread_mutex_unlock(&protows->mutex);
 420
 421                 if (writebuf_char(&wb, CHAR_FOR_SUBCALL_CALL)
 422                  && writebuf_uint32(&wb, sc->subcallid)
 423                  && writebuf_uint32(&wb, call->callid)
 424                  && writebuf_string(&wb, api)
 425                  && writebuf_string(&wb, verb)
 426                  && writebuf_object(&wb, args)) {
 427                         pthread_mutex_lock(&protows->mutex);
 428                         rc = afb_ws_binary_v(protows->ws, wb.iovec, wb.count);
 429                         pthread_mutex_unlock(&protows->mutex);
 430                         if (rc >= 0) {
 431                                 rc = 0;
 432                                 goto success;
 433                         }
 434                 }
 435         }
 436 success:
 437         return rc;
 438 }
 439
 440 int afb_proto_ws_call_subscribe(struct afb_proto_ws_call *call, const char *event_name, int event_id)
 441 {
 442         int rc = -1;
 443         struct writebuf wb = { .count = 0 };
 444         struct afb_proto_ws *protows = call->protows;
 445
 446         if (writebuf_char(&wb, CHAR_FOR_EVT_SUBSCRIBE)
 447          && writebuf_uint32(&wb, call->callid)
 448          && writebuf_uint32(&wb, (uint32_t)event_id)
 449          && writebuf_string(&wb, event_name)) {
 450                 pthread_mutex_lock(&protows->mutex);
 451                 rc = afb_ws_binary_v(protows->ws, wb.iovec, wb.count);
 452                 pthread_mutex_unlock(&protows->mutex);
 453                 if (rc >= 0) {
 454                         rc = 0;
 455                         goto success;
 456                 }
 457         }
 458 success:
 459         return rc;
 460 }
 461
 462 int afb_proto_ws_call_unsubscribe(struct afb_proto_ws_call *call, const char *event_name, int event_id)
 463 {
 464         int rc = -1;
 465         struct writebuf wb = { .count = 0 };
 466         struct afb_proto_ws *protows = call->protows;
 467
 468         if (writebuf_char(&wb, CHAR_FOR_EVT_UNSUBSCRIBE)
 469          && writebuf_uint32(&wb, call->callid)
 470          && writebuf_uint32(&wb, (uint32_t)event_id)
 471          && writebuf_string(&wb, event_name)) {
 472                 pthread_mutex_lock(&protows->mutex);
 473                 rc = afb_ws_binary_v(protows->ws, wb.iovec, wb.count);
 474                 pthread_mutex_unlock(&protows->mutex);
 475                 if (rc >= 0) {
 476                         rc = 0;
 477                         goto success;
 478                 }
 479         }
 480 success:
 481         return rc;
 482 }
 483
 484 /******************* client part **********************************/
 485
 486 /* search a memorized call */
 487 static struct client_call *client_call_search_locked(struct afb_proto_ws *protows, uint32_t callid)
 488 {
 489         struct client_call *call;
 490
 491         call = protows->calls;
 492         while (call != NULL && call->callid != callid)
 493                 call = call->next;
 494
 495         return call;
 496 }
 497
 498 static struct client_call *client_call_search_unlocked(struct afb_proto_ws *protows, uint32_t callid)
 499 {
 500         struct client_call *result;
 501
 502         pthread_mutex_lock(&protows->mutex);
 503         result = client_call_search_locked(protows, callid);
 504         pthread_mutex_unlock(&protows->mutex);
 505         return result;
 506 }
 507
 508 /* free and release the memorizing call */
 509 static void client_call_destroy(struct client_call *call)
 510 {
 511         struct client_call **prv;
 512         struct afb_proto_ws *protows = call->protows;
 513
 514         pthread_mutex_lock(&protows->mutex);
 515         prv = &call->protows->calls;
 516         while (*prv != NULL) {
 517                 if (*prv == call) {
 518                         *prv = call->next;
 519                         break;
 520                 }
 521                 prv = &(*prv)->next;
 522         }
 523         pthread_mutex_unlock(&protows->mutex);
 524         free(call);
 525 }
 526
 527 /* get event data from the message */
 528 static int client_msg_event_read(struct readbuf *rb, uint32_t *eventid, const char **name)
 529 {
 530         return readbuf_uint32(rb, eventid) && readbuf_string(rb, name, NULL);
 531 }
 532
 533 /* get event from the message */
 534 static int client_msg_call_get(struct afb_proto_ws *protows, struct readbuf *rb, struct client_call **call)
 535 {
 536         uint32_t callid;
 537
 538         /* get event data from the message */
 539         if (!readbuf_uint32(rb, &callid)) {
 540                 return 0;
 541         }
 542
 543         /* get the call */
 544         *call = client_call_search_unlocked(protows, callid);
 545         if (*call == NULL) {
 546                 return 0;
 547         }
 548
 549         return 1;
 550 }
 551
 552 /* adds an event */
 553 static void client_on_event_create(struct afb_proto_ws *protows, struct readbuf *rb)
 554 {
 555         const char *event_name;
 556         uint32_t event_id;
 557
 558         if (protows->client_itf->on_event_create && client_msg_event_read(rb, &event_id, &event_name))
 559                 protows->client_itf->on_event_create(protows->closure, event_name, (int)event_id);
 560 }
 561
 562 /* removes an event */
 563 static void client_on_event_remove(struct afb_proto_ws *protows, struct readbuf *rb)
 564 {
 565         const char *event_name;
 566         uint32_t event_id;
 567
 568         if (protows->client_itf->on_event_remove && client_msg_event_read(rb, &event_id, &event_name))
 569                 protows->client_itf->on_event_remove(protows->closure, event_name, (int)event_id);
 570 }
 571
 572 /* subscribes an event */
 573 static void client_on_event_subscribe(struct afb_proto_ws *protows, struct readbuf *rb)
 574 {
 575         const char *event_name;
 576         uint32_t event_id;
 577         struct client_call *call;
 578
 579         if (protows->client_itf->on_event_subscribe && client_msg_call_get(protows, rb, &call) && client_msg_event_read(rb, &event_id, &event_name))
 580                 protows->client_itf->on_event_subscribe(protows->closure, call->request, event_name, (int)event_id);
 581 }
 582
 583 /* unsubscribes an event */
 584 static void client_on_event_unsubscribe(struct afb_proto_ws *protows, struct readbuf *rb)
 585 {
 586         const char *event_name;
 587         uint32_t event_id;
 588         struct client_call *call;
 589
 590         if (protows->client_itf->on_event_unsubscribe && client_msg_call_get(protows, rb, &call) && client_msg_event_read(rb, &event_id, &event_name))
 591                 protows->client_itf->on_event_unsubscribe(protows->closure, call->request, event_name, (int)event_id);
 592 }
 593
 594 /* receives broadcasted events */
 595 static void client_on_event_broadcast(struct afb_proto_ws *protows, struct readbuf *rb)
 596 {
 597         const char *event_name;
 598         struct json_object *object;
 599
 600         if (protows->client_itf->on_event_broadcast && readbuf_string(rb, &event_name, NULL) && readbuf_object(rb, &object))
 601                 protows->client_itf->on_event_broadcast(protows->closure, event_name, object);
 602 }
 603
 604 /* pushs an event */
 605 static void client_on_event_push(struct afb_proto_ws *protows, struct readbuf *rb)
 606 {
 607         const char *event_name;
 608         uint32_t event_id;
 609         struct json_object *object;
 610
 611         if (protows->client_itf->on_event_push && client_msg_event_read(rb, &event_id, &event_name) && readbuf_object(rb, &object))
 612                 protows->client_itf->on_event_push(protows->closure, event_name, (int)event_id, object);
 613 }
 614
 615 static void client_on_reply_success(struct afb_proto_ws *protows, struct readbuf *rb)
 616 {
 617         struct client_call *call;
 618         struct json_object *object;
 619         const char *info;
 620
 621         if (!client_msg_call_get(protows, rb, &call))
 622                 return;
 623
 624         if (readbuf_string(rb, &info, NULL) && readbuf_object(rb, &object)) {
 625                 protows->client_itf->on_reply_success(protows->closure, call->request, object, info);
 626         } else {
 627                 protows->client_itf->on_reply_fail(protows->closure, call->request, "proto-error", "can't process success");
 628         }
 629         client_call_destroy(call);
 630 }
 631
 632 static void client_on_reply_fail(struct afb_proto_ws *protows, struct readbuf *rb)
 633 {
 634         struct client_call *call;
 635         const char *info, *status;
 636
 637         if (!client_msg_call_get(protows, rb, &call))
 638                 return;
 639
 640
 641         if (readbuf_string(rb, &status, NULL) && readbuf_string(rb, &info, NULL)) {
 642                 protows->client_itf->on_reply_fail(protows->closure, call->request, status, info);
 643         } else {
 644                 protows->client_itf->on_reply_fail(protows->closure, call->request, "proto-error", "can't process fail");
 645         }
 646         client_call_destroy(call);
 647 }
 648
 649 /* send a subcall reply */
 650 static int client_send_subcall_reply(struct afb_proto_ws *protows, uint32_t subcallid, int status, json_object *object)
 651 {
 652         struct writebuf wb = { .count = 0 };
 653         char ie = status < 0;
 654         int rc;
 655
 656         if (writebuf_char(&wb, CHAR_FOR_SUBCALL_REPLY)
 657          && writebuf_uint32(&wb, subcallid)
 658          && writebuf_char(&wb, ie)
 659          && writebuf_object(&wb, object)) {
 660                 pthread_mutex_lock(&protows->mutex);
 661                 rc = afb_ws_binary_v(protows->ws, wb.iovec, wb.count);
 662                 pthread_mutex_unlock(&protows->mutex);
 663                 if (rc >= 0)
 664                         return 0;
 665         }
 666         return -1;
 667 }
 668
 669 /* callback for subcall reply */
 670 int afb_proto_ws_subcall_reply(struct afb_proto_ws_subcall *subcall, int status, struct json_object *result)
 671 {
 672         int rc = client_send_subcall_reply(subcall->protows, subcall->subcallid, status, result);
 673         afb_proto_ws_unref(subcall->protows);
 674         free(subcall->buffer);
 675         free(subcall);
 676         return rc;
 677 }
 678
 679 /* received a subcall request */
 680 static void client_on_subcall(struct afb_proto_ws *protows, struct readbuf *rb)
 681 {
 682         struct afb_proto_ws_subcall *subcall;
 683         struct client_call *call;
 684         const char *api, *verb;
 685         uint32_t subcallid;
 686         struct json_object *object;
 687
 688         /* get the subcallid */
 689         if (!readbuf_uint32(rb, &subcallid))
 690                 return;
 691
 692         /* if not expected drop it */
 693         if (!protows->client_itf->on_subcall)
 694                 goto error;
 695
 696         /* retrieve the message data */
 697         if (!client_msg_call_get(protows, rb, &call))
 698                 goto error;
 699
 700         /* allocation of the subcall */
 701         subcall = malloc(sizeof *subcall);
 702         if (!subcall)
 703                 goto error;
 704
 705         /* make the call */
 706         if (readbuf_string(rb, &api, NULL)
 707          && readbuf_string(rb, &verb, NULL)
 708          && readbuf_object(rb, &object)) {
 709                 afb_proto_ws_addref(protows);
 710                 subcall->protows = protows;
 711                 subcall->subcallid = subcallid;
 712                 subcall->buffer = rb->base;
 713                 rb->base = NULL;
 714                 protows->client_itf->on_subcall(protows->closure, subcall, call->request, api, verb, object);
 715                 return;
 716         }
 717         free(subcall);
 718 error:
 719         client_send_subcall_reply(protows, subcallid, 1, NULL);
 720 }
 721
 722 static void client_on_description(struct afb_proto_ws *protows, struct readbuf *rb)
 723 {
 724         uint32_t descid;
 725         struct client_describe *desc, **prv;
 726         struct json_object *object;
 727
 728         if (readbuf_uint32(rb, &descid)) {
 729                 pthread_mutex_lock(&protows->mutex);
 730                 prv = &protows->describes;
 731                 while ((desc = *prv) && desc->descid != descid)
 732                         prv = &desc->next;
 733                 if (!desc)
 734                         pthread_mutex_unlock(&protows->mutex);
 735                 else {
 736                         *prv = desc->next;
 737                         pthread_mutex_unlock(&protows->mutex);
 738                         if (!readbuf_object(rb, &object))
 739                                 object = NULL;
 740                         desc->callback(desc->closure, object);
 741                         free(desc);
 742                 }
 743         }
 744 }
 745
 746 /* callback when receiving binary data */
 747 static void client_on_binary_job(int sig, void *closure)
 748 {
 749         struct binary *binary = closure;
 750
 751         if (!sig) {
 752                 switch (*binary->rb.head++) {
 753                 case CHAR_FOR_ANSWER_SUCCESS: /* success */
 754                         client_on_reply_success(binary->protows, &binary->rb);
 755                         break;
 756                 case CHAR_FOR_ANSWER_FAIL: /* fail */
 757                         client_on_reply_fail(binary->protows, &binary->rb);
 758                         break;
 759                 case CHAR_FOR_EVT_BROADCAST: /* broadcast */
 760                         client_on_event_broadcast(binary->protows, &binary->rb);
 761                         break;
 762                 case CHAR_FOR_EVT_ADD: /* creates the event */
 763                         client_on_event_create(binary->protows, &binary->rb);
 764                         break;
 765                 case CHAR_FOR_EVT_DEL: /* removes the event */
 766                         client_on_event_remove(binary->protows, &binary->rb);
 767                         break;
 768                 case CHAR_FOR_EVT_PUSH: /* pushs the event */
 769                         client_on_event_push(binary->protows, &binary->rb);
 770                         break;
 771                 case CHAR_FOR_EVT_SUBSCRIBE: /* subscribe event for a request */
 772                         client_on_event_subscribe(binary->protows, &binary->rb);
 773                         break;
 774                 case CHAR_FOR_EVT_UNSUBSCRIBE: /* unsubscribe event for a request */
 775                         client_on_event_unsubscribe(binary->protows, &binary->rb);
 776                         break;
 777                 case CHAR_FOR_SUBCALL_CALL: /* subcall */
 778                         client_on_subcall(binary->protows, &binary->rb);
 779                         break;
 780                 case CHAR_FOR_DESCRIPTION: /* description */
 781                         client_on_description(binary->protows, &binary->rb);
 782                         break;
 783                 default: /* unexpected message */
 784                         /* TODO: close the connection */
 785                         break;
 786                 }
 787         }
 788         free(binary->rb.base);
 789         free(binary);
 790 }
 791
 792 /* callback when receiving binary data */
 793 static void client_on_binary(void *closure, char *data, size_t size)
 794 {
 795         int rc;
 796         struct binary *binary;
 797
 798         if (size) {
 799                 binary = malloc(sizeof *binary);
 800                 if (!binary) {
 801                         errno = ENOMEM;
 802                 } else {
 803                         binary->protows = closure;
 804                         binary->rb.base = data;
 805                         binary->rb.head = data;
 806                         binary->rb.end = data + size;
 807                         rc = jobs_queue(NULL, 0, client_on_binary_job, binary);
 808                         if (rc >= 0)
 809                                 return;
 810                         free(binary);
 811                 }
 812         }
 813         free(data);
 814 }
 815
 816 int afb_proto_ws_client_call(
 817                 struct afb_proto_ws *protows,
 818                 const char *verb,
 819                 struct json_object *args,
 820                 const char *sessionid,
 821                 void *request
 822 )
 823 {
 824         int rc = -1;
 825         struct client_call *call;
 826         struct writebuf wb = { .count = 0 };
 827
 828         /* allocate call data */
 829         call = malloc(sizeof *call);
 830         if (call == NULL) {
 831                 errno = ENOMEM;
 832                 return -1;
 833         }
 834         call->request = request;
 835
 836         /* init call data */
 837         pthread_mutex_lock(&protows->mutex);
 838         call->callid = ptr2id(call);
 839         while(client_call_search_locked(protows, call->callid) != NULL)
 840                 call->callid++;
 841         call->protows = protows;
 842         call->next = protows->calls;
 843         protows->calls = call;
 844         pthread_mutex_unlock(&protows->mutex);
 845
 846         /* creates the call message */
 847         if (!writebuf_char(&wb, CHAR_FOR_CALL)
 848          || !writebuf_uint32(&wb, call->callid)
 849          || !writebuf_string(&wb, verb)
 850          || !writebuf_string(&wb, sessionid)
 851          || !writebuf_object(&wb, args)) {
 852                 errno = EINVAL;
 853                 goto clean;
 854         }
 855
 856         /* send */
 857         pthread_mutex_lock(&protows->mutex);
 858         rc = afb_ws_binary_v(protows->ws, wb.iovec, wb.count);
 859         pthread_mutex_unlock(&protows->mutex);
 860         if (rc >= 0) {
 861                 rc = 0;
 862                 goto end;
 863         }
 864
 865 clean:
 866         client_call_destroy(call);
 867 end:
 868         return rc;
 869 }
 870
 871 /* get the description */
 872 int afb_proto_ws_client_describe(struct afb_proto_ws *protows, void (*callback)(void*, struct json_object*), void *closure)
 873 {
 874         struct client_describe *desc, *d;
 875         struct writebuf wb = { .count = 0 };
 876
 877         desc = malloc(sizeof *desc);
 878         if (!desc) {
 879                 errno = ENOMEM;
 880                 goto error;
 881         }
 882
 883         /* fill in stack the description of the task */
 884         pthread_mutex_lock(&protows->mutex);
 885         desc->descid = ptr2id(desc);
 886         d = protows->describes;
 887         while (d) {
 888                 if (d->descid != desc->descid)
 889                         d = d->next;
 890                 else {
 891                         desc->descid++;
 892                         d = protows->describes;
 893                 }
 894         }
 895         desc->callback = callback;
 896         desc->closure = closure;
 897         desc->protows = protows;
 898         desc->next = protows->describes;
 899         protows->describes = desc;
 900
 901         /* send */
 902         if (writebuf_char(&wb, CHAR_FOR_DESCRIBE)
 903          && writebuf_uint32(&wb, desc->descid)
 904          && afb_ws_binary_v(protows->ws, wb.iovec, wb.count) >= 0) {
 905                 pthread_mutex_unlock(&protows->mutex);
 906                 return 0;
 907         }
 908
 909         d = protows->describes;
 910         if (d == desc)
 911                 protows->describes = desc->next;
 912         else {
 913                 while(d && d->next != desc)
 914                         d = d->next;
 915                 if (d)
 916                         d->next = desc->next;
 917         }
 918         pthread_mutex_unlock(&protows->mutex);
 919         free(desc);
 920 error:
 921         /* TODO? callback(closure, NULL); */
 922         return -1;
 923 }
 924
 925 /******************* client description part for server *****************************/
 926
 927 /* on call, propagate it to the ws service */
 928 static void server_on_call(struct afb_proto_ws *protows, struct readbuf *rb)
 929 {
 930         struct afb_proto_ws_call *call;
 931         const char *uuid, *verb;
 932         uint32_t callid;
 933         size_t lenverb;
 934         struct json_object *object;
 935
 936         afb_proto_ws_addref(protows);
 937
 938         /* reads the call message data */
 939         if (!readbuf_uint32(rb, &callid)
 940          || !readbuf_string(rb, &verb, &lenverb)
 941          || !readbuf_string(rb, &uuid, NULL)
 942          || !readbuf_object(rb, &object))
 943                 goto overflow;
 944
 945         /* create the request */
 946         call = malloc(sizeof *call);
 947         if (call == NULL)
 948                 goto out_of_memory;
 949
 950         call->protows = protows;
 951         call->callid = callid;
 952         call->refcount = 1;
 953         call->buffer = rb->base;
 954         rb->base = NULL; /* don't free the buffer */
 955
 956         protows->server_itf->on_call(protows->closure, call, verb, object, uuid);
 957         return;
 958
 959 out_of_memory:
 960         json_object_put(object);
 961
 962 overflow:
 963         afb_proto_ws_unref(protows);
 964 }
 965
 966 /* on subcall reply */
 967 static void server_on_subcall_reply(struct afb_proto_ws *protows, struct readbuf *rb)
 968 {
 969         char ie;
 970         uint32_t subcallid;
 971         struct json_object *object;
 972         struct server_subcall *sc, **psc;
 973
 974         /* reads the call message data */
 975         if (!readbuf_uint32(rb, &subcallid)
 976          || !readbuf_char(rb, &ie)
 977          || !readbuf_object(rb, &object)) {
 978                 /* TODO bad protocol */
 979                 return;
 980         }
 981
 982         /* search the subcall and unlink it */
 983         pthread_mutex_lock(&protows->mutex);
 984         psc = &protows->subcalls;
 985         while ((sc = *psc) && sc->subcallid != subcallid)
 986                 psc = &sc->next;
 987         if (!sc) {
 988                 pthread_mutex_unlock(&protows->mutex);
 989                 json_object_put(object);
 990                 /* TODO subcall not found */
 991         } else {
 992                 *psc = sc->next;
 993                 pthread_mutex_unlock(&protows->mutex);
 994                 sc->callback(sc->closure, -(int)ie, object);
 995                 free(sc);
 996         }
 997 }
 998
 999 static int server_send_description(struct afb_proto_ws *protows, uint32_t descid, struct json_object *descobj)
1000 {
1001         int rc;
1002         struct writebuf wb = { .count = 0 };
1003
1004         if (writebuf_char(&wb, CHAR_FOR_DESCRIPTION)
1005          && writebuf_uint32(&wb, descid)
1006          && writebuf_object(&wb, descobj)) {
1007                 pthread_mutex_lock(&protows->mutex);
1008                 rc = afb_ws_binary_v(protows->ws, wb.iovec, wb.count);
1009                 pthread_mutex_unlock(&protows->mutex);
1010                 if (rc >= 0)
1011                         return 0;
1012         }
1013         return -1;
1014 }
1015
1016 int afb_proto_ws_describe_put(struct afb_proto_ws_describe *describe, struct json_object *description)
1017 {
1018         int rc = server_send_description(describe->protows, describe->descid, description);
1019         afb_proto_ws_unref(describe->protows);
1020         free(describe);
1021         return rc;
1022 }
1023
1024 /* on describe, propagate it to the ws service */
1025 static void server_on_describe(struct afb_proto_ws *protows, struct readbuf *rb)
1026 {
1027         uint32_t descid;
1028         struct afb_proto_ws_describe *desc;
1029
1030         /* reads the descid */
1031         if (readbuf_uint32(rb, &descid)) {
1032                 if (protows->server_itf->on_describe) {
1033                         /* create asynchronous job */
1034                         desc = malloc(sizeof *desc);
1035                         if (desc) {
1036                                 desc->descid = descid;
1037                                 desc->protows = protows;
1038                                 afb_proto_ws_addref(protows);
1039                                 protows->server_itf->on_describe(protows->closure, desc);
1040                                 return;
1041                         }
1042                 }
1043                 server_send_description(protows, descid, NULL);
1044         }
1045 }
1046
1047 /* callback when receiving binary data */
1048 static void server_on_binary_job(int sig, void *closure)
1049 {
1050         struct binary *binary = closure;
1051
1052         if (!sig) {
1053                 switch (*binary->rb.head++) {
1054                 case CHAR_FOR_CALL:
1055                         server_on_call(binary->protows, &binary->rb);
1056                         break;
1057                 case CHAR_FOR_SUBCALL_REPLY:
1058                         server_on_subcall_reply(binary->protows, &binary->rb);
1059                         break;
1060                 case CHAR_FOR_DESCRIBE:
1061                         server_on_describe(binary->protows, &binary->rb);
1062                         break;
1063                 default: /* unexpected message */
1064                         /* TODO: close the connection */
1065                         break;
1066                 }
1067         }
1068         free(binary->rb.base);
1069         free(binary);
1070 }
1071
1072 static void server_on_binary(void *closure, char *data, size_t size)
1073 {
1074         int rc;
1075         struct binary *binary;
1076
1077         if (size) {
1078                 binary = malloc(sizeof *binary);
1079                 if (!binary) {
1080                         errno = ENOMEM;
1081                 } else {
1082                         binary->protows = closure;
1083                         binary->rb.base = data;
1084                         binary->rb.head = data;
1085                         binary->rb.end = data + size;
1086                         rc = jobs_queue(NULL, 0, server_on_binary_job, binary);
1087                         if (rc >= 0)
1088                                 return;
1089                         free(binary);
1090                 }
1091         }
1092         free(data);
1093 }
1094
1095 /******************* server part: manage events **********************************/
1096
1097 static int server_event_send(struct afb_proto_ws *protows, char order, const char *event_name, int event_id, struct json_object *data)
1098 {
1099         struct writebuf wb = { .count = 0 };
1100         int rc;
1101
1102         if (writebuf_char(&wb, order)
1103          && (order == CHAR_FOR_EVT_BROADCAST || writebuf_uint32(&wb, event_id))
1104          && writebuf_string(&wb, event_name)
1105          && (order == CHAR_FOR_EVT_ADD || order == CHAR_FOR_EVT_DEL || writebuf_object(&wb, data))) {
1106                 pthread_mutex_lock(&protows->mutex);
1107                 rc = afb_ws_binary_v(protows->ws, wb.iovec, wb.count);
1108                 pthread_mutex_unlock(&protows->mutex);
1109                 if (rc >= 0)
1110                         return 0;
1111         }
1112         return -1;
1113 }
1114
1115 int afb_proto_ws_server_event_create(struct afb_proto_ws *protows, const char *event_name, int event_id)
1116 {
1117         return server_event_send(protows, CHAR_FOR_EVT_ADD, event_name, event_id, NULL);
1118 }
1119
1120 int afb_proto_ws_server_event_remove(struct afb_proto_ws *protows, const char *event_name, int event_id)
1121 {
1122         return server_event_send(protows, CHAR_FOR_EVT_DEL, event_name, event_id, NULL);
1123 }
1124
1125 int afb_proto_ws_server_event_push(struct afb_proto_ws *protows, const char *event_name, int event_id, struct json_object *data)
1126 {
1127         return server_event_send(protows, CHAR_FOR_EVT_PUSH, event_name, event_id, data);
1128 }
1129
1130 int afb_proto_ws_server_event_broadcast(struct afb_proto_ws *protows, const char *event_name, struct json_object *data)
1131 {
1132         return server_event_send(protows, CHAR_FOR_EVT_BROADCAST, event_name, 0, data);
1133 }
1134
1135 /*****************************************************/
1136
1137 /* callback when receiving a hangup */
1138 static void on_hangup(void *closure)
1139 {
1140         struct afb_proto_ws *protows = closure;
1141         struct server_subcall *sc, *nsc;
1142         struct client_describe *cd, *ncd;
1143
1144         nsc = protows->subcalls;
1145         while (nsc) {
1146                 sc= nsc;
1147                 nsc = sc->next;
1148                 sc->callback(sc->closure, 1, NULL);
1149                 free(sc);
1150         }
1151
1152         ncd = protows->describes;
1153         while (ncd) {
1154                 cd= ncd;
1155                 ncd = cd->next;
1156                 cd->callback(cd->closure, NULL);
1157                 free(cd);
1158         }
1159
1160         if (protows->fd >= 0) {
1161                 close(protows->fd);
1162                 protows->fd = -1;
1163                 if (protows->on_hangup)
1164                         protows->on_hangup(protows->closure);
1165         }
1166 }
1167
1168 /*****************************************************/
1169
1170 static const struct afb_ws_itf proto_ws_client_ws_itf =
1171 {
1172         .on_close = NULL,
1173         .on_text = NULL,
1174         .on_binary = client_on_binary,
1175         .on_error = NULL,
1176         .on_hangup = on_hangup
1177 };
1178
1179 static const struct afb_ws_itf server_ws_itf =
1180 {
1181         .on_close = NULL,
1182         .on_text = NULL,
1183         .on_binary = server_on_binary,
1184         .on_error = NULL,
1185         .on_hangup = on_hangup
1186 };
1187
1188 /*****************************************************/
1189
1190 static struct afb_proto_ws *afb_proto_ws_create(struct sd_event *eloop, int fd, const struct afb_proto_ws_server_itf *itfs, const struct afb_proto_ws_client_itf *itfc, void *closure, const struct afb_ws_itf *itf)
1191 {
1192         struct afb_proto_ws *protows;
1193
1194         protows = calloc(1, sizeof *protows);
1195         if (protows == NULL)
1196                 errno = ENOMEM;
1197         else {
1198                 fcntl(fd, F_SETFD, FD_CLOEXEC);
1199                 fcntl(fd, F_SETFL, O_NONBLOCK);
1200                 protows->ws = afb_ws_create(eloop, fd, itf, protows);
1201                 if (protows->ws != NULL) {
1202                         protows->fd = fd;
1203                         protows->refcount = 1;
1204                         protows->subcalls = NULL;
1205                         protows->closure = closure;
1206                         protows->server_itf = itfs;
1207                         protows->client_itf = itfc;
1208                         pthread_mutex_init(&protows->mutex, NULL);
1209                         return protows;
1210                 }
1211                 free(protows);
1212         }
1213         return NULL;
1214 }
1215
1216 struct afb_proto_ws *afb_proto_ws_create_client(struct sd_event *eloop, int fd, const struct afb_proto_ws_client_itf *itf, void *closure)
1217 {
1218         return afb_proto_ws_create(eloop, fd, NULL, itf, closure, &proto_ws_client_ws_itf);
1219 }
1220
1221 struct afb_proto_ws *afb_proto_ws_create_server(struct sd_event *eloop, int fd, const struct afb_proto_ws_server_itf *itf, void *closure)
1222 {
1223         return afb_proto_ws_create(eloop, fd, itf, NULL, closure, &server_ws_itf);
1224 }
1225
1226 void afb_proto_ws_unref(struct afb_proto_ws *protows)
1227 {
1228         if (!__atomic_sub_fetch(&protows->refcount, 1, __ATOMIC_RELAXED)) {
1229                 afb_proto_ws_hangup(protows);
1230                 afb_ws_destroy(protows->ws);
1231                 pthread_mutex_destroy(&protows->mutex);
1232                 free(protows);
1233         }
1234 }
1235
1236 void afb_proto_ws_addref(struct afb_proto_ws *protows)
1237 {
1238         __atomic_add_fetch(&protows->refcount, 1, __ATOMIC_RELAXED);
1239 }
1240
1241 int afb_proto_ws_is_client(struct afb_proto_ws *protows)
1242 {
1243         return !!protows->client_itf;
1244 }
1245
1246 int afb_proto_ws_is_server(struct afb_proto_ws *protows)
1247 {
1248         return !!protows->server_itf;
1249 }
1250
1251 void afb_proto_ws_hangup(struct afb_proto_ws *protows)
1252 {
1253         afb_ws_hangup(protows->ws);
1254 }
1255
1256 void afb_proto_ws_on_hangup(struct afb_proto_ws *protows, void (*on_hangup)(void *closure))
1257 {
1258         protows->on_hangup = on_hangup;
1259 }
1260