lib/service.c

   1 /*
   2  * libwebsockets - small server side websockets and web server implementation
   3  *
   4  * Copyright (C) 2010-2015 Andy Green <andy@warmcat.com>
   5  *
   6  *  This library is free software; you can redistribute it and/or
   7  *  modify it under the terms of the GNU Lesser General Public
   8  *  License as published by the Free Software Foundation:
   9  *  version 2.1 of the License.
  10  *
  11  *  This library is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  *  Lesser General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU Lesser General Public
  17  *  License along with this library; if not, write to the Free Software
  18  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  19  *  MA  02110-1301  USA
  20  */
  21
  22 #include "private-libwebsockets.h"
  23
  24 static int
  25 lws_calllback_as_writeable(struct lws *wsi)
  26 {
  27         struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];
  28         int n;
  29
  30         lws_stats_atomic_bump(wsi->context, pt, LWSSTATS_C_WRITEABLE_CB, 1);
  31 #if defined(LWS_WITH_STATS)
  32         {
  33                 uint64_t ul = time_in_microseconds() - wsi->active_writable_req_us;
  34
  35                 lws_stats_atomic_bump(wsi->context, pt, LWSSTATS_MS_WRITABLE_DELAY, ul);
  36                 lws_stats_atomic_max(wsi->context, pt, LWSSTATS_MS_WORST_WRITABLE_DELAY, ul);
  37                 wsi->active_writable_req_us = 0;
  38         }
  39 #endif
  40
  41         switch (wsi->mode) {
  42         case LWSCM_RAW:
  43                 n = LWS_CALLBACK_RAW_WRITEABLE;
  44                 break;
  45         case LWSCM_RAW_FILEDESC:
  46                 n = LWS_CALLBACK_RAW_WRITEABLE_FILE;
  47                 break;
  48         case LWSCM_WS_CLIENT:
  49                 n = LWS_CALLBACK_CLIENT_WRITEABLE;
  50                 break;
  51         case LWSCM_WSCL_ISSUE_HTTP_BODY:
  52                 n = LWS_CALLBACK_CLIENT_HTTP_WRITEABLE;
  53                 break;
  54         case LWSCM_WS_SERVING:
  55                 n = LWS_CALLBACK_SERVER_WRITEABLE;
  56                 break;
  57         default:
  58                 n = LWS_CALLBACK_HTTP_WRITEABLE;
  59                 break;
  60         }
  61
  62         return user_callback_handle_rxflow(wsi->protocol->callback,
  63                                            wsi, (enum lws_callback_reasons) n,
  64                                            wsi->user_space, NULL, 0);
  65 }
  66
  67 LWS_VISIBLE int
  68 lws_handle_POLLOUT_event(struct lws *wsi, struct lws_pollfd *pollfd)
  69 {
  70         int write_type = LWS_WRITE_PONG;
  71         struct lws_tokens eff_buf;
  72 #ifdef LWS_USE_HTTP2
  73         struct lws *wsi2;
  74 #endif
  75         int ret, m, n;
  76
  77 //      lwsl_err("%s: %p\n", __func__, wsi);
  78
  79         wsi->leave_pollout_active = 0;
  80         wsi->handling_pollout = 1;
  81         /*
  82          * if another thread wants POLLOUT on us, from here on while
  83          * handling_pollout is set, he will only set leave_pollout_active.
  84          * If we are going to disable POLLOUT, we will check that first.
  85          */
  86
  87         /*
  88          * user callback is lowest priority to get these notifications
  89          * actually, since other pending things cannot be disordered
  90          */
  91
  92         /* Priority 1: pending truncated sends are incomplete ws fragments
  93          *             If anything else sent first the protocol would be
  94          *             corrupted.
  95          */
  96         if (wsi->trunc_len) {
  97                 if (lws_issue_raw(wsi, wsi->trunc_alloc + wsi->trunc_offset,
  98                                   wsi->trunc_len) < 0) {
  99                         lwsl_info("%s signalling to close\n", __func__);
 100                         goto bail_die;
 101                 }
 102                 /* leave POLLOUT active either way */
 103                 goto bail_ok;
 104         } else
 105                 if (wsi->state == LWSS_FLUSHING_STORED_SEND_BEFORE_CLOSE) {
 106                         wsi->socket_is_permanently_unusable = 1;
 107                         goto bail_die; /* retry closing now */
 108                 }
 109
 110         if (wsi->mode == LWSCM_WSCL_ISSUE_HTTP_BODY)
 111                 goto user_service;
 112
 113
 114 #ifdef LWS_USE_HTTP2
 115         /* Priority 2: protocol packets
 116          */
 117         if (wsi->pps) {
 118                 lwsl_info("servicing pps %d\n", wsi->pps);
 119                 switch (wsi->pps) {
 120                 case LWS_PPS_HTTP2_MY_SETTINGS:
 121                 case LWS_PPS_HTTP2_ACK_SETTINGS:
 122                         lws_http2_do_pps_send(lws_get_context(wsi), wsi);
 123                         break;
 124                 default:
 125                         break;
 126                 }
 127                 wsi->pps = LWS_PPS_NONE;
 128                 lws_rx_flow_control(wsi, 1);
 129
 130                 goto bail_ok; /* leave POLLOUT active */
 131         }
 132 #endif
 133
 134 #ifdef LWS_WITH_CGI
 135         if (wsi->cgi) {
 136                 /* also one shot */
 137                 if (pollfd)
 138                         if (lws_change_pollfd(wsi, LWS_POLLOUT, 0)) {
 139                                 lwsl_info("failed at set pollfd\n");
 140                                 return 1;
 141                         }
 142                 goto user_service_go_again;
 143         }
 144 #endif
 145
 146         /* Priority 3: pending control packets (pong or close)
 147          *
 148          * 3a: close notification packet requested from close api
 149          */
 150
 151         if (wsi->state == LWSS_WAITING_TO_SEND_CLOSE_NOTIFICATION) {
 152                 lwsl_debug("sending close packet\n");
 153                 wsi->waiting_to_send_close_frame = 0;
 154                 n = lws_write(wsi, &wsi->u.ws.ping_payload_buf[LWS_PRE],
 155                               wsi->u.ws.close_in_ping_buffer_len,
 156                               LWS_WRITE_CLOSE);
 157                 if (n >= 0) {
 158                         wsi->state = LWSS_AWAITING_CLOSE_ACK;
 159                         lws_set_timeout(wsi, PENDING_TIMEOUT_CLOSE_ACK, 1);
 160                         lwsl_debug("sent close indication, awaiting ack\n");
 161
 162                         goto bail_ok;
 163                 }
 164
 165                 goto bail_die;
 166         }
 167
 168         /* else, the send failed and we should just hang up */
 169
 170         if ((wsi->state == LWSS_ESTABLISHED &&
 171              wsi->u.ws.ping_pending_flag) ||
 172             (wsi->state == LWSS_RETURNED_CLOSE_ALREADY &&
 173              wsi->u.ws.payload_is_close)) {
 174
 175                 if (wsi->u.ws.payload_is_close)
 176                         write_type = LWS_WRITE_CLOSE;
 177
 178                 n = lws_write(wsi, &wsi->u.ws.ping_payload_buf[LWS_PRE],
 179                               wsi->u.ws.ping_payload_len, write_type);
 180                 if (n < 0)
 181                         goto bail_die;
 182
 183                 /* well he is sent, mark him done */
 184                 wsi->u.ws.ping_pending_flag = 0;
 185                 if (wsi->u.ws.payload_is_close)
 186                         /* oh... a close frame was it... then we are done */
 187                         goto bail_die;
 188
 189                 /* otherwise for PING, leave POLLOUT active either way */
 190                 goto bail_ok;
 191         }
 192
 193         if (wsi->state == LWSS_ESTABLISHED &&
 194             !wsi->socket_is_permanently_unusable &&
 195             wsi->u.ws.send_check_ping) {
 196
 197                 lwsl_info("issuing ping on wsi %p\n", wsi);
 198                 wsi->u.ws.send_check_ping = 0;
 199                 n = lws_write(wsi, &wsi->u.ws.ping_payload_buf[LWS_PRE],
 200                               0, LWS_WRITE_PING);
 201                 if (n < 0)
 202                         goto bail_die;
 203
 204                 /*
 205                  * we apparently were able to send the PING in a reasonable time
 206                  * now reset the clock on our peer to be able to send the
 207                  * PONG in a reasonable time.
 208                  */
 209
 210                 lws_set_timeout(wsi, PENDING_TIMEOUT_WS_PONG_CHECK_GET_PONG,
 211                                 wsi->context->timeout_secs);
 212
 213                 goto bail_ok;
 214         }
 215
 216         /* Priority 4: if we are closing, not allowed to send more data frags
 217          *             which means user callback or tx ext flush banned now
 218          */
 219         if (wsi->state == LWSS_RETURNED_CLOSE_ALREADY)
 220                 goto user_service;
 221
 222         /* Priority 5: Tx path extension with more to send
 223          *
 224          *             These are handled as new fragments each time around
 225          *             So while we must block new writeable callback to enforce
 226          *             payload ordering, but since they are always complete
 227          *             fragments control packets can interleave OK.
 228          */
 229         if (wsi->state == LWSS_ESTABLISHED && wsi->u.ws.tx_draining_ext) {
 230                 lwsl_ext("SERVICING TX EXT DRAINING\n");
 231                 if (lws_write(wsi, NULL, 0, LWS_WRITE_CONTINUATION) < 0)
 232                         goto bail_die;
 233                 /* leave POLLOUT active */
 234                 goto bail_ok;
 235         }
 236
 237         /* Priority 6: user can get the callback
 238          */
 239         m = lws_ext_cb_active(wsi, LWS_EXT_CB_IS_WRITEABLE, NULL, 0);
 240         if (m)
 241                 goto bail_die;
 242 #ifndef LWS_NO_EXTENSIONS
 243         if (!wsi->extension_data_pending)
 244                 goto user_service;
 245 #endif
 246         /*
 247          * check in on the active extensions, see if they
 248          * had pending stuff to spill... they need to get the
 249          * first look-in otherwise sequence will be disordered
 250          *
 251          * NULL, zero-length eff_buf means just spill pending
 252          */
 253
 254         ret = 1;
 255         if (wsi->mode == LWSCM_RAW || wsi->mode == LWSCM_RAW_FILEDESC)
 256                 ret = 0;
 257         while (ret == 1) {
 258
 259                 /* default to nobody has more to spill */
 260
 261                 ret = 0;
 262                 eff_buf.token = NULL;
 263                 eff_buf.token_len = 0;
 264
 265                 /* give every extension a chance to spill */
 266
 267                 m = lws_ext_cb_active(wsi,
 268                                         LWS_EXT_CB_PACKET_TX_PRESEND,
 269                                                &eff_buf, 0);
 270                 if (m < 0) {
 271                         lwsl_err("ext reports fatal error\n");
 272                         goto bail_die;
 273                 }
 274                 if (m)
 275                         /*
 276                          * at least one extension told us he has more
 277                          * to spill, so we will go around again after
 278                          */
 279                         ret = 1;
 280
 281                 /* assuming they gave us something to send, send it */
 282
 283                 if (eff_buf.token_len) {
 284                         n = lws_issue_raw(wsi, (unsigned char *)eff_buf.token,
 285                                           eff_buf.token_len);
 286                         if (n < 0) {
 287                                 lwsl_info("closing from POLLOUT spill\n");
 288                                 goto bail_die;
 289                         }
 290                         /*
 291                          * Keep amount spilled small to minimize chance of this
 292                          */
 293                         if (n != eff_buf.token_len) {
 294                                 lwsl_err("Unable to spill ext %d vs %d\n",
 295                                                           eff_buf.token_len, n);
 296                                 goto bail_die;
 297                         }
 298                 } else
 299                         continue;
 300
 301                 /* no extension has more to spill */
 302
 303                 if (!ret)
 304                         continue;
 305
 306                 /*
 307                  * There's more to spill from an extension, but we just sent
 308                  * something... did that leave the pipe choked?
 309                  */
 310
 311                 if (!lws_send_pipe_choked(wsi))
 312                         /* no we could add more */
 313                         continue;
 314
 315                 lwsl_info("choked in POLLOUT service\n");
 316
 317                 /*
 318                  * Yes, he's choked.  Leave the POLLOUT masked on so we will
 319                  * come back here when he is unchoked.  Don't call the user
 320                  * callback to enforce ordering of spilling, he'll get called
 321                  * when we come back here and there's nothing more to spill.
 322                  */
 323
 324                 goto bail_ok;
 325         }
 326 #ifndef LWS_NO_EXTENSIONS
 327         wsi->extension_data_pending = 0;
 328 #endif
 329 user_service:
 330         /* one shot */
 331
 332         if (wsi->parent_carries_io) {
 333                 wsi->handling_pollout = 0;
 334                 wsi->leave_pollout_active = 0;
 335
 336                 return lws_calllback_as_writeable(wsi);
 337         }
 338
 339         if (pollfd) {
 340                 int eff = wsi->leave_pollout_active;
 341
 342                 if (!eff)
 343                         if (lws_change_pollfd(wsi, LWS_POLLOUT, 0)) {
 344                                 lwsl_info("failed at set pollfd\n");
 345                                 goto bail_die;
 346                         }
 347
 348                 wsi->handling_pollout = 0;
 349
 350                 /* cannot get leave_pollout_active set after the above */
 351                 if (!eff && wsi->leave_pollout_active)
 352                         /* got set inbetween sampling eff and clearing
 353                          * handling_pollout, force POLLOUT on */
 354                         lws_calllback_as_writeable(wsi);
 355
 356                 wsi->leave_pollout_active = 0;
 357         }
 358
 359         if (wsi->mode != LWSCM_WSCL_ISSUE_HTTP_BODY &&
 360             !wsi->hdr_parsing_completed)
 361                 goto bail_ok;
 362
 363
 364 #ifdef LWS_WITH_CGI
 365 user_service_go_again:
 366 #endif
 367
 368 #ifdef LWS_USE_HTTP2
 369         /*
 370          * we are the 'network wsi' for potentially many muxed child wsi with
 371          * no network connection of their own, who have to use us for all their
 372          * network actions.  So we use a round-robin scheme to share out the
 373          * POLLOUT notifications to our children.
 374          *
 375          * But because any child could exhaust the socket's ability to take
 376          * writes, we can only let one child get notified each time.
 377          *
 378          * In addition children may be closed / deleted / added between POLLOUT
 379          * notifications, so we can't hold pointers
 380          */
 381
 382         if (wsi->mode != LWSCM_HTTP2_SERVING) {
 383                 lwsl_info("%s: non http2\n", __func__);
 384                 goto notify;
 385         }
 386
 387         wsi->u.http2.requested_POLLOUT = 0;
 388         if (!wsi->u.http2.initialized) {
 389                 lwsl_info("pollout on uninitialized http2 conn\n");
 390                 goto bail_ok;
 391         }
 392
 393         lwsl_info("%s: doing children\n", __func__);
 394
 395         wsi2 = wsi;
 396         do {
 397                 wsi2 = wsi2->u.http2.next_child_wsi;
 398                 lwsl_info("%s: child %p\n", __func__, wsi2);
 399                 if (!wsi2)
 400                         continue;
 401                 if (!wsi2->u.http2.requested_POLLOUT)
 402                         continue;
 403                 wsi2->u.http2.requested_POLLOUT = 0;
 404                 if (lws_calllback_as_writeable(wsi2)) {
 405                         lwsl_debug("Closing POLLOUT child\n");
 406                         lws_close_free_wsi(wsi2, LWS_CLOSE_STATUS_NOSTATUS);
 407                 }
 408                 wsi2 = wsi;
 409         } while (wsi2 != NULL && !lws_send_pipe_choked(wsi));
 410
 411         lwsl_info("%s: completed\n", __func__);
 412
 413         goto bail_ok;
 414 notify:
 415 #endif
 416         wsi->handling_pollout = 0;
 417         wsi->leave_pollout_active = 0;
 418
 419         return lws_calllback_as_writeable(wsi);
 420
 421         /*
 422          * since these don't disable the POLLOUT, they are always doing the
 423          * right thing for leave_pollout_active whether it was set or not.
 424          */
 425
 426 bail_ok:
 427         wsi->handling_pollout = 0;
 428         wsi->leave_pollout_active = 0;
 429
 430         return 0;
 431
 432 bail_die:
 433         wsi->handling_pollout = 0;
 434         wsi->leave_pollout_active = 0;
 435
 436         return -1;
 437 }
 438
 439 int
 440 lws_service_timeout_check(struct lws *wsi, unsigned int sec)
 441 {
 442 //#if LWS_POSIX
 443         struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];
 444         int n = 0;
 445 //#endif
 446
 447         (void)n;
 448
 449         /*
 450          * if extensions want in on it (eg, we are a mux parent)
 451          * give them a chance to service child timeouts
 452          */
 453         if (lws_ext_cb_active(wsi, LWS_EXT_CB_1HZ, NULL, sec) < 0)
 454                 return 0;
 455
 456         if (!wsi->pending_timeout)
 457                 return 0;
 458
 459         /*
 460          * if we went beyond the allowed time, kill the
 461          * connection
 462          */
 463         if ((time_t)sec > wsi->pending_timeout_limit) {
 464 //#if LWS_POSIX
 465                 if (wsi->desc.sockfd != LWS_SOCK_INVALID && wsi->position_in_fds_table >= 0)
 466                         n = pt->fds[wsi->position_in_fds_table].events;
 467
 468                 lws_stats_atomic_bump(wsi->context, pt, LWSSTATS_C_TIMEOUTS, 1);
 469
 470                 /* no need to log normal idle keepalive timeout */
 471                 if (wsi->pending_timeout != PENDING_TIMEOUT_HTTP_KEEPALIVE_IDLE)
 472                         lwsl_notice("wsi %p: TIMEDOUT WAITING on %d (did hdr %d, ah %p, wl %d, pfd events %d) %llu vs %llu\n",
 473                             (void *)wsi, wsi->pending_timeout,
 474                             wsi->hdr_parsing_completed, wsi->u.hdr.ah,
 475                             pt->ah_wait_list_length, n, (unsigned long long)sec, (unsigned long long)wsi->pending_timeout_limit);
 476 //#endif
 477                 /*
 478                  * Since he failed a timeout, he already had a chance to do
 479                  * something and was unable to... that includes situations like
 480                  * half closed connections.  So process this "failed timeout"
 481                  * close as a violent death and don't try to do protocol
 482                  * cleanup like flush partials.
 483                  */
 484                 wsi->socket_is_permanently_unusable = 1;
 485                 if (wsi->mode == LWSCM_WSCL_WAITING_SSL)
 486                         wsi->vhost->protocols[0].callback(wsi,
 487                                 LWS_CALLBACK_CLIENT_CONNECTION_ERROR,
 488                                 wsi->user_space, (void *)"Timed out waiting SSL", 21);
 489
 490                 lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
 491
 492                 return 1;
 493         }
 494
 495         return 0;
 496 }
 497
 498 int lws_rxflow_cache(struct lws *wsi, unsigned char *buf, int n, int len)
 499 {
 500         /* his RX is flowcontrolled, don't send remaining now */
 501         if (wsi->rxflow_buffer) {
 502                 /* rxflow while we were spilling prev rxflow */
 503                 lwsl_info("stalling in existing rxflow buf\n");
 504                 return 1;
 505         }
 506
 507         /* a new rxflow, buffer it and warn caller */
 508         lwsl_info("new rxflow input buffer len %d\n", len - n);
 509         wsi->rxflow_buffer = lws_malloc(len - n);
 510         if (!wsi->rxflow_buffer)
 511                 return -1;
 512         wsi->rxflow_len = len - n;
 513         wsi->rxflow_pos = 0;
 514         memcpy(wsi->rxflow_buffer, buf + n, len - n);
 515
 516         return 0;
 517 }
 518
 519 /* this is used by the platform service code to stop us waiting for network
 520  * activity in poll() when we have something that already needs service
 521  */
 522
 523 LWS_VISIBLE LWS_EXTERN int
 524 lws_service_adjust_timeout(struct lws_context *context, int timeout_ms, int tsi)
 525 {
 526         struct lws_context_per_thread *pt = &context->pt[tsi];
 527         int n;
 528
 529         /* Figure out if we really want to wait in poll()
 530          * We only need to wait if really nothing already to do and we have
 531          * to wait for something from network
 532          */
 533
 534         /* 1) if we know we are draining rx ext, do not wait in poll */
 535         if (pt->rx_draining_ext_list)
 536                 return 0;
 537
 538 #ifdef LWS_OPENSSL_SUPPORT
 539         /* 2) if we know we have non-network pending data, do not wait in poll */
 540         if (lws_ssl_anybody_has_buffered_read_tsi(context, tsi)) {
 541                 lwsl_info("ssl buffered read\n");
 542                 return 0;
 543         }
 544 #endif
 545
 546         /* 3) if any ah has pending rx, do not wait in poll */
 547         for (n = 0; n < context->max_http_header_pool; n++)
 548                 if (pt->ah_pool[n].rxpos != pt->ah_pool[n].rxlen) {
 549                         /* any ah with pending rx must be attached to someone */
 550                         if (!pt->ah_pool[n].wsi) {
 551                                 lwsl_err("%s: assert: no wsi attached to ah\n", __func__);
 552                                 assert(0);
 553                         }
 554                         return 0;
 555                 }
 556
 557         return timeout_ms;
 558 }
 559
 560 /*
 561  * guys that need POLLIN service again without waiting for network action
 562  * can force POLLIN here if not flowcontrolled, so they will get service.
 563  *
 564  * Return nonzero if anybody got their POLLIN faked
 565  */
 566 int
 567 lws_service_flag_pending(struct lws_context *context, int tsi)
 568 {
 569         struct lws_context_per_thread *pt = &context->pt[tsi];
 570 #ifdef LWS_OPENSSL_SUPPORT
 571         struct lws *wsi_next;
 572 #endif
 573         struct lws *wsi;
 574         int forced = 0;
 575         int n;
 576
 577         /* POLLIN faking */
 578
 579         /*
 580          * 1) For all guys with already-available ext data to drain, if they are
 581          * not flowcontrolled, fake their POLLIN status
 582          */
 583         wsi = pt->rx_draining_ext_list;
 584         while (wsi) {
 585                 pt->fds[wsi->position_in_fds_table].revents |=
 586                         pt->fds[wsi->position_in_fds_table].events & LWS_POLLIN;
 587                 if (pt->fds[wsi->position_in_fds_table].revents & LWS_POLLIN) {
 588                         forced = 1;
 589                         break;
 590                 }
 591                 wsi = wsi->u.ws.rx_draining_ext_list;
 592         }
 593
 594 #ifdef LWS_OPENSSL_SUPPORT
 595         /*
 596          * 2) For all guys with buffered SSL read data already saved up, if they
 597          * are not flowcontrolled, fake their POLLIN status so they'll get
 598          * service to use up the buffered incoming data, even though their
 599          * network socket may have nothing
 600          */
 601         wsi = pt->pending_read_list;
 602         while (wsi) {
 603                 wsi_next = wsi->pending_read_list_next;
 604                 pt->fds[wsi->position_in_fds_table].revents |=
 605                         pt->fds[wsi->position_in_fds_table].events & LWS_POLLIN;
 606                 if (pt->fds[wsi->position_in_fds_table].revents & LWS_POLLIN) {
 607                         forced = 1;
 608                         /*
 609                          * he's going to get serviced now, take him off the
 610                          * list of guys with buffered SSL.  If he still has some
 611                          * at the end of the service, he'll get put back on the
 612                          * list then.
 613                          */
 614                         lws_ssl_remove_wsi_from_buffered_list(wsi);
 615                 }
 616
 617                 wsi = wsi_next;
 618         }
 619 #endif
 620         /*
 621          * 3) For any wsi who have an ah with pending RX who did not
 622          * complete their current headers, and are not flowcontrolled,
 623          * fake their POLLIN status so they will be able to drain the
 624          * rx buffered in the ah
 625          */
 626         for (n = 0; n < context->max_http_header_pool; n++)
 627                 if (pt->ah_pool[n].rxpos != pt->ah_pool[n].rxlen &&
 628                     !pt->ah_pool[n].wsi->hdr_parsing_completed) {
 629                         pt->fds[pt->ah_pool[n].wsi->position_in_fds_table].revents |=
 630                                 pt->fds[pt->ah_pool[n].wsi->position_in_fds_table].events &
 631                                         LWS_POLLIN;
 632                         if (pt->fds[pt->ah_pool[n].wsi->position_in_fds_table].revents &
 633                             LWS_POLLIN)
 634                                 forced = 1;
 635                 }
 636
 637         return forced;
 638 }
 639
 640 #ifndef LWS_NO_CLIENT
 641
 642 LWS_VISIBLE int
 643 lws_http_client_read(struct lws *wsi, char **buf, int *len)
 644 {
 645         int rlen, n;
 646
 647         rlen = lws_ssl_capable_read(wsi, (unsigned char *)*buf, *len);
 648         *len = 0;
 649
 650         /* allow the source to signal he has data again next time */
 651         lws_change_pollfd(wsi, 0, LWS_POLLIN);
 652
 653         if (rlen == LWS_SSL_CAPABLE_ERROR) {
 654                 lwsl_notice("%s: SSL capable error\n", __func__);
 655                 return -1;
 656         }
 657
 658         if (rlen == 0)
 659                 return -1;
 660
 661         if (rlen < 0)
 662                 return 0;
 663
 664         *len = rlen;
 665         wsi->client_rx_avail = 0;
 666
 667         /*
 668          * server may insist on transfer-encoding: chunked,
 669          * so http client must deal with it
 670          */
 671 spin_chunks:
 672         while (wsi->chunked && (wsi->chunk_parser != ELCP_CONTENT) && *len) {
 673                 switch (wsi->chunk_parser) {
 674                 case ELCP_HEX:
 675                         if ((*buf)[0] == '\x0d') {
 676                                 wsi->chunk_parser = ELCP_CR;
 677                                 break;
 678                         }
 679                         n = char_to_hex((*buf)[0]);
 680                         if (n < 0) {
 681                                 lwsl_debug("chunking failure\n");
 682                                 return -1;
 683                         }
 684                         wsi->chunk_remaining <<= 4;
 685                         wsi->chunk_remaining |= n;
 686                         break;
 687                 case ELCP_CR:
 688                         if ((*buf)[0] != '\x0a') {
 689                                 lwsl_debug("chunking failure\n");
 690                                 return -1;
 691                         }
 692                         wsi->chunk_parser = ELCP_CONTENT;
 693                         lwsl_info("chunk %d\n", wsi->chunk_remaining);
 694                         if (wsi->chunk_remaining)
 695                                 break;
 696                         lwsl_info("final chunk\n");
 697                         goto completed;
 698
 699                 case ELCP_CONTENT:
 700                         break;
 701
 702                 case ELCP_POST_CR:
 703                         if ((*buf)[0] != '\x0d') {
 704                                 lwsl_debug("chunking failure\n");
 705
 706                                 return -1;
 707                         }
 708
 709                         wsi->chunk_parser = ELCP_POST_LF;
 710                         break;
 711
 712                 case ELCP_POST_LF:
 713                         if ((*buf)[0] != '\x0a')
 714                                 return -1;
 715
 716                         wsi->chunk_parser = ELCP_HEX;
 717                         wsi->chunk_remaining = 0;
 718                         break;
 719                 }
 720                 (*buf)++;
 721                 (*len)--;
 722         }
 723
 724         if (wsi->chunked && !wsi->chunk_remaining)
 725                 return 0;
 726
 727         if (wsi->u.http.content_remain &&
 728             wsi->u.http.content_remain < *len)
 729                 n = (int)wsi->u.http.content_remain;
 730         else
 731                 n = *len;
 732
 733         if (wsi->chunked && wsi->chunk_remaining &&
 734             wsi->chunk_remaining < n)
 735                 n = wsi->chunk_remaining;
 736
 737 #ifdef LWS_WITH_HTTP_PROXY
 738         /* hubbub */
 739         if (wsi->perform_rewrite)
 740                 lws_rewrite_parse(wsi->rw, (unsigned char *)*buf, n);
 741         else
 742 #endif
 743                 if (user_callback_handle_rxflow(wsi->protocol->callback,
 744                                 wsi, LWS_CALLBACK_RECEIVE_CLIENT_HTTP_READ,
 745                                 wsi->user_space, *buf, n)) {
 746                         lwsl_debug("%s: LWS_CALLBACK_RECEIVE_CLIENT_HTTP_READ returned -1\n", __func__);
 747
 748                         return -1;
 749                 }
 750
 751         if (wsi->chunked && wsi->chunk_remaining) {
 752                 (*buf) += n;
 753                 wsi->chunk_remaining -= n;
 754                 *len -= n;
 755         }
 756
 757         if (wsi->chunked && !wsi->chunk_remaining)
 758                 wsi->chunk_parser = ELCP_POST_CR;
 759
 760         if (wsi->chunked && *len)
 761                 goto spin_chunks;
 762
 763         if (wsi->chunked)
 764                 return 0;
 765
 766         /* if we know the content length, decrement the content remaining */
 767         if (wsi->u.http.content_length > 0)
 768                 wsi->u.http.content_remain -= n;
 769
 770         if (wsi->u.http.content_remain || !wsi->u.http.content_length)
 771                 return 0;
 772
 773 completed:
 774         if (user_callback_handle_rxflow(wsi->protocol->callback,
 775                         wsi, LWS_CALLBACK_COMPLETED_CLIENT_HTTP,
 776                         wsi->user_space, NULL, 0)) {
 777                 lwsl_debug("Completed call returned -1\n");
 778                 return -1;
 779         }
 780
 781         if (lws_http_transaction_completed_client(wsi)) {
 782                 lwsl_notice("%s: transaction completed says -1\n", __func__);
 783                 return -1;
 784         }
 785
 786         return 0;
 787 }
 788 #endif
 789
 790 static int
 791 lws_is_ws_with_ext(struct lws *wsi)
 792 {
 793 #if defined(LWS_NO_EXTENSIONS)
 794         return 0;
 795 #else
 796         return wsi->state == LWSS_ESTABLISHED &&
 797                !!wsi->count_act_ext;
 798 #endif
 799 }
 800
 801 LWS_VISIBLE int
 802 lws_service_fd_tsi(struct lws_context *context, struct lws_pollfd *pollfd, int tsi)
 803 {
 804         struct lws_context_per_thread *pt = &context->pt[tsi];
 805         lws_sockfd_type our_fd = 0, tmp_fd;
 806         struct lws_tokens eff_buf;
 807         unsigned int pending = 0;
 808         struct lws *wsi, *wsi1;
 809         char draining_flow = 0;
 810         int timed_out = 0;
 811         time_t now;
 812         int n = 0, m;
 813         int more;
 814
 815         if (!context->protocol_init_done)
 816                 lws_protocol_init(context);
 817
 818         time(&now);
 819
 820         /*
 821          * handle case that system time was uninitialized when lws started
 822          * at boot, and got initialized a little later
 823          */
 824         if (context->time_up < 1464083026 && now > 1464083026)
 825                 context->time_up = now;
 826
 827         /* TODO: if using libev, we should probably use timeout watchers... */
 828         if (context->last_timeout_check_s != now) {
 829                 context->last_timeout_check_s = now;
 830
 831 #if defined(LWS_WITH_STATS)
 832                 if (!tsi && now - context->last_dump > 10) {
 833                         lws_stats_log_dump(context);
 834                         context->last_dump = now;
 835                 }
 836 #endif
 837
 838                 lws_plat_service_periodic(context);
 839
 840                 lws_check_deferred_free(context, 0);
 841
 842                 /* retire unused deprecated context */
 843 #if !defined(LWS_PLAT_OPTEE) && !defined(LWS_WITH_ESP32)
 844 #if LWS_POSIX && !defined(_WIN32)
 845                 if (context->deprecated && !context->count_wsi_allocated) {
 846                         lwsl_notice("%s: ending deprecated context\n", __func__);
 847                         kill(getpid(), SIGINT);
 848                         return 0;
 849                 }
 850 #endif
 851 #endif
 852                 /* global timeout check once per second */
 853
 854                 if (pollfd)
 855                         our_fd = pollfd->fd;
 856
 857                 wsi = context->pt[tsi].timeout_list;
 858                 while (wsi) {
 859                         /* we have to take copies, because he may be deleted */
 860                         wsi1 = wsi->timeout_list;
 861                         tmp_fd = wsi->desc.sockfd;
 862                         if (lws_service_timeout_check(wsi, (unsigned int)now)) {
 863                                 /* he did time out... */
 864                                 if (tmp_fd == our_fd)
 865                                         /* it was the guy we came to service! */
 866                                         timed_out = 1;
 867                                         /* he's gone, no need to mark as handled */
 868                         }
 869                         wsi = wsi1;
 870                 }
 871 #ifdef LWS_WITH_CGI
 872                 lws_cgi_kill_terminated(pt);
 873 #endif
 874 #if 0
 875                 {
 876                         char s[300], *p = s;
 877
 878                         for (n = 0; n < context->count_threads; n++)
 879                                 p += sprintf(p, " %7lu (%5d), ",
 880                                              context->pt[n].count_conns,
 881                                              context->pt[n].fds_count);
 882
 883                         lwsl_notice("load: %s\n", s);
 884                 }
 885 #endif
 886         }
 887
 888         /*
 889          * at intervals, check for ws connections needing ping-pong checks
 890          */
 891
 892         if (context->ws_ping_pong_interval &&
 893             context->last_ws_ping_pong_check_s < now + 10) {
 894                 struct lws_vhost *vh = context->vhost_list;
 895                 context->last_ws_ping_pong_check_s = now;
 896
 897                 while (vh) {
 898                         for (n = 0; n < vh->count_protocols; n++) {
 899                                 wsi = vh->same_vh_protocol_list[n];
 900
 901                                 while (wsi) {
 902                                         if (wsi->state == LWSS_ESTABLISHED &&
 903                                             !wsi->socket_is_permanently_unusable &&
 904                                             !wsi->u.ws.send_check_ping &&
 905                                             wsi->u.ws.time_next_ping_check &&
 906                                             wsi->u.ws.time_next_ping_check < now) {
 907
 908                                                 lwsl_info("requesting ping-pong on wsi %p\n", wsi);
 909                                                 wsi->u.ws.send_check_ping = 1;
 910                                                 lws_set_timeout(wsi, PENDING_TIMEOUT_WS_PONG_CHECK_SEND_PING,
 911                                                                 context->timeout_secs);
 912                                                 lws_callback_on_writable(wsi);
 913                                                 wsi->u.ws.time_next_ping_check = now +
 914                                                                 wsi->context->ws_ping_pong_interval;
 915                                         }
 916                                         wsi = wsi->same_vh_protocol_next;
 917                                 }
 918                         }
 919                         vh = vh->vhost_next;
 920                 }
 921         }
 922
 923         /* the socket we came to service timed out, nothing to do */
 924         if (timed_out)
 925                 return 0;
 926
 927         /* just here for timeout management? */
 928         if (!pollfd)
 929                 return 0;
 930
 931         /* no, here to service a socket descriptor */
 932         wsi = wsi_from_fd(context, pollfd->fd);
 933         if (!wsi)
 934                 /* not lws connection ... leave revents alone and return */
 935                 return 0;
 936
 937         /*
 938          * so that caller can tell we handled, past here we need to
 939          * zero down pollfd->revents after handling
 940          */
 941
 942 #if LWS_POSIX
 943         /* handle session socket closed */
 944
 945         if ((!(pollfd->revents & pollfd->events & LWS_POLLIN)) &&
 946             (pollfd->revents & LWS_POLLHUP)) {
 947                 wsi->socket_is_permanently_unusable = 1;
 948                 lwsl_debug("Session Socket %p (fd=%d) dead\n",
 949                                                        (void *)wsi, pollfd->fd);
 950
 951                 goto close_and_handled;
 952         }
 953
 954 #ifdef _WIN32
 955         if (pollfd->revents & LWS_POLLOUT)
 956                 wsi->sock_send_blocking = FALSE;
 957 #endif
 958
 959 #endif
 960
 961 //       lwsl_debug("fd=%d, revents=%d, mode=%d, state=%d\n", pollfd->fd, pollfd->revents, (int)wsi->mode, (int)wsi->state);
 962         if (pollfd->revents & LWS_POLLHUP) {
 963                 lwsl_debug("pollhup\n");
 964                 wsi->socket_is_permanently_unusable = 1;
 965                 goto close_and_handled;
 966         }
 967
 968
 969 #ifdef LWS_OPENSSL_SUPPORT
 970         if ((wsi->state == LWSS_SHUTDOWN) && lws_is_ssl(wsi) && wsi->ssl)
 971         {
 972                 n = SSL_shutdown(wsi->ssl);
 973                 lwsl_debug("SSL_shutdown=%d for fd %d\n", n, wsi->desc.sockfd);
 974                 if (n == 1)
 975                 {
 976                         n = shutdown(wsi->desc.sockfd, SHUT_WR);
 977                         goto close_and_handled;
 978                 }
 979                 else if (n == 0)
 980                 {
 981                         lws_change_pollfd(wsi, LWS_POLLOUT, LWS_POLLIN);
 982                         n = 0;
 983                         goto handled;
 984                 }
 985                 else /* n < 0 */
 986                 {
 987                         int shutdown_error = SSL_get_error(wsi->ssl, n);
 988                         lwsl_debug("SSL_shutdown returned %d, SSL_get_error: %d\n", n, shutdown_error);
 989                         if (shutdown_error == SSL_ERROR_WANT_READ) {
 990                                 lws_change_pollfd(wsi, LWS_POLLOUT, LWS_POLLIN);
 991                                 n = 0;
 992                                 goto handled;
 993                         } else if (shutdown_error == SSL_ERROR_WANT_WRITE) {
 994                                 lws_change_pollfd(wsi, LWS_POLLOUT, LWS_POLLOUT);
 995                                 n = 0;
 996                                 goto handled;
 997                         }
 998
 999                         // actual error occurred, just close the connection
1000                         n = shutdown(wsi->desc.sockfd, SHUT_WR);
1001                         goto close_and_handled;
1002                 }
1003         }
1004 #endif
1005
1006         /* okay, what we came here to do... */
1007
1008         switch (wsi->mode) {
1009         case LWSCM_HTTP_SERVING:
1010         case LWSCM_HTTP_CLIENT:
1011         case LWSCM_HTTP_SERVING_ACCEPTED:
1012         case LWSCM_SERVER_LISTENER:
1013         case LWSCM_SSL_ACK_PENDING:
1014         case LWSCM_SSL_ACK_PENDING_RAW:
1015                 if (wsi->state == LWSS_CLIENT_HTTP_ESTABLISHED)
1016                         goto handled;
1017
1018 #ifdef LWS_WITH_CGI
1019                 if (wsi->cgi && (pollfd->revents & LWS_POLLOUT)) {
1020                         n = lws_handle_POLLOUT_event(wsi, pollfd);
1021                         if (n)
1022                                 goto close_and_handled;
1023                         goto handled;
1024                 }
1025 #endif
1026                 /* fallthru */
1027         case LWSCM_RAW:
1028                 n = lws_server_socket_service(context, wsi, pollfd);
1029                 if (n) /* closed by above */
1030                         return 1;
1031                 goto handled;
1032
1033         case LWSCM_RAW_FILEDESC:
1034
1035                 if (pollfd->revents & LWS_POLLOUT) {
1036                         n = lws_calllback_as_writeable(wsi);
1037                         if (lws_change_pollfd(wsi, LWS_POLLOUT, 0)) {
1038                                 lwsl_info("failed at set pollfd\n");
1039                                 return 1;
1040                         }
1041                         if (n)
1042                                 goto close_and_handled;
1043                 }
1044                 n = LWS_CALLBACK_RAW_RX;
1045                 if (wsi->mode == LWSCM_RAW_FILEDESC)
1046                         n = LWS_CALLBACK_RAW_RX_FILE;
1047
1048                 if (pollfd->revents & LWS_POLLIN) {
1049                         if (user_callback_handle_rxflow(
1050                                         wsi->protocol->callback,
1051                                         wsi, n,
1052                                         wsi->user_space, NULL, 0)) {
1053                                 lwsl_debug("raw rx callback closed it\n");
1054                                 goto close_and_handled;
1055                         }
1056                 }
1057
1058                 if (pollfd->revents & LWS_POLLHUP)
1059                         goto close_and_handled;
1060                 n = 0;
1061                 goto handled;
1062
1063         case LWSCM_WS_SERVING:
1064         case LWSCM_WS_CLIENT:
1065         case LWSCM_HTTP2_SERVING:
1066         case LWSCM_HTTP_CLIENT_ACCEPTED:
1067
1068                 /* 1: something requested a callback when it was OK to write */
1069
1070                 if (wsi->state == LWSS_WAITING_TO_SEND_CLOSE_NOTIFICATION)
1071                         lwsl_notice("xxx\n");
1072
1073                 if ((pollfd->revents & LWS_POLLOUT) &&
1074                     ((wsi->state == LWSS_ESTABLISHED ||
1075                      wsi->state == LWSS_HTTP2_ESTABLISHED ||
1076                      wsi->state == LWSS_HTTP2_ESTABLISHED_PRE_SETTINGS ||
1077                      wsi->state == LWSS_RETURNED_CLOSE_ALREADY ||
1078                      wsi->state == LWSS_WAITING_TO_SEND_CLOSE_NOTIFICATION ||
1079                      wsi->state == LWSS_FLUSHING_STORED_SEND_BEFORE_CLOSE)) &&
1080                     lws_handle_POLLOUT_event(wsi, pollfd)) {
1081                         if (wsi->state == LWSS_RETURNED_CLOSE_ALREADY)
1082                                 wsi->state = LWSS_FLUSHING_STORED_SEND_BEFORE_CLOSE;
1083                         lwsl_info("lws_service_fd: closing\n");
1084                         goto close_and_handled;
1085                 }
1086
1087                 if (wsi->state == LWSS_RETURNED_CLOSE_ALREADY ||
1088                     wsi->state == LWSS_WAITING_TO_SEND_CLOSE_NOTIFICATION ||
1089                     wsi->state == LWSS_AWAITING_CLOSE_ACK) {
1090                         /*
1091                          * we stopped caring about anything except control
1092                          * packets.  Force flow control off, defeat tx
1093                          * draining.
1094                          */
1095                         lws_rx_flow_control(wsi, 1);
1096                         wsi->u.ws.tx_draining_ext = 0;
1097                 }
1098
1099                 if (wsi->u.ws.tx_draining_ext)
1100                         /* we cannot deal with new RX until the TX ext
1101                          * path has been drained.  It's because new
1102                          * rx will, eg, crap on the wsi rx buf that
1103                          * may be needed to retain state.
1104                          *
1105                          * TX ext drain path MUST go through event loop
1106                          * to avoid blocking.
1107                          */
1108                         break;
1109
1110                 if (!(wsi->rxflow_change_to & LWS_RXFLOW_ALLOW))
1111                         /* We cannot deal with any kind of new RX
1112                          * because we are RX-flowcontrolled.
1113                          */
1114                         break;
1115
1116                 /* 2: RX Extension needs to be drained
1117                  */
1118
1119                 if (wsi->state == LWSS_ESTABLISHED &&
1120                     wsi->u.ws.rx_draining_ext) {
1121
1122                         lwsl_ext("%s: RX EXT DRAINING: Service\n", __func__);
1123 #ifndef LWS_NO_CLIENT
1124                         if (wsi->mode == LWSCM_WS_CLIENT) {
1125                                 n = lws_client_rx_sm(wsi, 0);
1126                                 if (n < 0)
1127                                         /* we closed wsi */
1128                                         n = 0;
1129                         } else
1130 #endif
1131                                 n = lws_rx_sm(wsi, 0);
1132
1133                         goto handled;
1134                 }
1135
1136                 if (wsi->u.ws.rx_draining_ext)
1137                         /*
1138                          * We have RX EXT content to drain, but can't do it
1139                          * right now.  That means we cannot do anything lower
1140                          * priority either.
1141                          */
1142                         break;
1143
1144                 /* 3: RX Flowcontrol buffer needs to be drained
1145                  */
1146
1147                 if (wsi->rxflow_buffer) {
1148                         lwsl_info("draining rxflow (len %d)\n",
1149                                 wsi->rxflow_len - wsi->rxflow_pos
1150                         );
1151                         /* well, drain it */
1152                         eff_buf.token = (char *)wsi->rxflow_buffer +
1153                                                 wsi->rxflow_pos;
1154                         eff_buf.token_len = wsi->rxflow_len - wsi->rxflow_pos;
1155                         draining_flow = 1;
1156                         goto drain;
1157                 }
1158
1159                 /* 4: any incoming (or ah-stashed incoming rx) data ready?
1160                  * notice if rx flow going off raced poll(), rx flow wins
1161                  */
1162
1163                 if (!(pollfd->revents & pollfd->events & LWS_POLLIN))
1164                         break;
1165
1166 read:
1167                 /* all the union members start with hdr, so even in ws mode
1168                  * we can deal with the ah via u.hdr
1169                  */
1170                 if (wsi->u.hdr.ah) {
1171                         lwsl_info("%s: %p: inherited ah rx\n", __func__, wsi);
1172                         eff_buf.token_len = wsi->u.hdr.ah->rxlen -
1173                                             wsi->u.hdr.ah->rxpos;
1174                         eff_buf.token = (char *)wsi->u.hdr.ah->rx +
1175                                         wsi->u.hdr.ah->rxpos;
1176                 } else {
1177                         if (wsi->mode != LWSCM_HTTP_CLIENT_ACCEPTED) {
1178                                 /*
1179                                  * extension may not consume everything (eg, pmd may be constrained
1180                                  * as to what it can output...) has to go in per-wsi rx buf area.
1181                                  * Otherwise in large temp serv_buf area.
1182                                  */
1183                                 eff_buf.token = (char *)pt->serv_buf;
1184                                 if (lws_is_ws_with_ext(wsi)) {
1185                                         eff_buf.token_len = wsi->u.ws.rx_ubuf_alloc;
1186                                 } else {
1187                                         eff_buf.token_len = context->pt_serv_buf_size;
1188                                 }
1189
1190                                 if ((unsigned int)eff_buf.token_len > context->pt_serv_buf_size)
1191                                         eff_buf.token_len = context->pt_serv_buf_size;
1192
1193                                 eff_buf.token_len = lws_ssl_capable_read(wsi,
1194                                         (unsigned char *)eff_buf.token, pending ? pending :
1195                                         eff_buf.token_len);
1196                                 switch (eff_buf.token_len) {
1197                                 case 0:
1198                                         lwsl_info("%s: zero length read\n", __func__);
1199                                         goto close_and_handled;
1200                                 case LWS_SSL_CAPABLE_MORE_SERVICE:
1201                                         lwsl_info("SSL Capable more service\n");
1202                                         n = 0;
1203                                         goto handled;
1204                                 case LWS_SSL_CAPABLE_ERROR:
1205                                         lwsl_info("Closing when error\n");
1206                                         goto close_and_handled;
1207                                 }
1208                                 // lwsl_notice("Actual RX %d\n", eff_buf.token_len);
1209                         }
1210                 }
1211
1212 drain:
1213 #ifndef LWS_NO_CLIENT
1214                 if (wsi->mode == LWSCM_HTTP_CLIENT_ACCEPTED &&
1215                     !wsi->told_user_closed) {
1216
1217                         /*
1218                          * In SSL mode we get POLLIN notification about
1219                          * encrypted data in.
1220                          *
1221                          * But that is not necessarily related to decrypted
1222                          * data out becoming available; in may need to perform
1223                          * other in or out before that happens.
1224                          *
1225                          * simply mark ourselves as having readable data
1226                          * and turn off our POLLIN
1227                          */
1228                         wsi->client_rx_avail = 1;
1229                         lws_change_pollfd(wsi, LWS_POLLIN, 0);
1230
1231                         /* let user code know, he'll usually ask for writeable
1232                          * callback and drain / re-enable it there
1233                          */
1234                         if (user_callback_handle_rxflow(
1235                                         wsi->protocol->callback,
1236                                         wsi, LWS_CALLBACK_RECEIVE_CLIENT_HTTP,
1237                                         wsi->user_space, NULL, 0)) {
1238                                 lwsl_notice("LWS_CALLBACK_RECEIVE_CLIENT_HTTP closed it\n");
1239                                 goto close_and_handled;
1240                         }
1241
1242                         n = 0;
1243                         goto handled;
1244                 }
1245 #endif
1246                 /*
1247                  * give any active extensions a chance to munge the buffer
1248                  * before parse.  We pass in a pointer to an lws_tokens struct
1249                  * prepared with the default buffer and content length that's in
1250                  * there.  Rather than rewrite the default buffer, extensions
1251                  * that expect to grow the buffer can adapt .token to
1252                  * point to their own per-connection buffer in the extension
1253                  * user allocation.  By default with no extensions or no
1254                  * extension callback handling, just the normal input buffer is
1255                  * used then so it is efficient.
1256                  */
1257                 do {
1258                         more = 0;
1259
1260                         m = lws_ext_cb_active(wsi, LWS_EXT_CB_PACKET_RX_PREPARSE,
1261                                               &eff_buf, 0);
1262                         if (m < 0)
1263                                 goto close_and_handled;
1264                         if (m)
1265                                 more = 1;
1266
1267                         /* service incoming data */
1268
1269                         if (eff_buf.token_len) {
1270                                 /*
1271                                  * if draining from rxflow buffer, not
1272                                  * critical to track what was used since at the
1273                                  * use it bumps wsi->rxflow_pos.  If we come
1274                                  * around again it will pick up from where it
1275                                  * left off.
1276                                  */
1277                                 // lwsl_notice("doing lws_read from pt->serv_buf %p %p for len %d\n", pt->serv_buf, eff_buf.token, (int)eff_buf.token_len);
1278
1279                                 n = lws_read(wsi, (unsigned char *)eff_buf.token,
1280                                              eff_buf.token_len);
1281                                 if (n < 0) {
1282                                         /* we closed wsi */
1283                                         n = 0;
1284                                         goto handled;
1285                                 }
1286                         }
1287
1288                         eff_buf.token = NULL;
1289                         eff_buf.token_len = 0;
1290                 } while (more);
1291
1292                 if (wsi->u.hdr.ah) {
1293                         lwsl_notice("%s: %p: detaching\n",
1294                                  __func__, wsi);
1295                         lws_header_table_force_to_detachable_state(wsi);
1296                         /* we can run the normal ah detach flow despite
1297                          * being in ws union mode, since all union members
1298                          * start with hdr */
1299                         lws_header_table_detach(wsi, 0);
1300                 }
1301
1302                 pending = lws_ssl_pending(wsi);
1303                 if (pending) {
1304                         if (lws_is_ws_with_ext(wsi))
1305                                 pending = pending > wsi->u.ws.rx_ubuf_alloc ?
1306                                         wsi->u.ws.rx_ubuf_alloc : pending;
1307                         else
1308                                 pending = pending > context->pt_serv_buf_size ?
1309                                         context->pt_serv_buf_size : pending;
1310                         goto read;
1311                 }
1312
1313                 if (draining_flow && wsi->rxflow_buffer &&
1314                     wsi->rxflow_pos == wsi->rxflow_len) {
1315                         lwsl_info("flow buffer: drained\n");
1316                         lws_free_set_NULL(wsi->rxflow_buffer);
1317                         /* having drained the rxflow buffer, can rearm POLLIN */
1318 #ifdef LWS_NO_SERVER
1319                         n =
1320 #endif
1321                         _lws_rx_flow_control(wsi);
1322                         /* n ignored, needed for NO_SERVER case */
1323                 }
1324
1325                 break;
1326 #ifdef LWS_WITH_CGI
1327         case LWSCM_CGI: /* we exist to handle a cgi's stdin/out/err data...
1328                          * do the callback on our master wsi
1329                          */
1330                 {
1331                         struct lws_cgi_args args;
1332
1333                         if (wsi->cgi_channel >= LWS_STDOUT &&
1334                             !(pollfd->revents & pollfd->events & LWS_POLLIN))
1335                                 break;
1336                         if (wsi->cgi_channel == LWS_STDIN &&
1337                             !(pollfd->revents & pollfd->events & LWS_POLLOUT))
1338                                 break;
1339
1340                         if (wsi->cgi_channel == LWS_STDIN)
1341                                 if (lws_change_pollfd(wsi, LWS_POLLOUT, 0)) {
1342                                         lwsl_info("failed at set pollfd\n");
1343                                         return 1;
1344                                 }
1345
1346                         args.ch = wsi->cgi_channel;
1347                         args.stdwsi = &wsi->parent->cgi->stdwsi[0];
1348                         args.hdr_state = wsi->hdr_state;
1349
1350                         //lwsl_err("CGI LWS_STDOUT waiting wsi %p mode %d state %d\n",
1351                         //       wsi->parent, wsi->parent->mode, wsi->parent->state);
1352
1353                         if (user_callback_handle_rxflow(
1354                                         wsi->parent->protocol->callback,
1355                                         wsi->parent, LWS_CALLBACK_CGI,
1356                                         wsi->parent->user_space,
1357                                         (void *)&args, 0))
1358                                 return 1;
1359
1360                         break;
1361                 }
1362 #endif
1363         default:
1364 #ifdef LWS_NO_CLIENT
1365                 break;
1366 #else
1367                 if ((pollfd->revents & LWS_POLLOUT) &&
1368                     lws_handle_POLLOUT_event(wsi, pollfd)) {
1369                         lwsl_debug("POLLOUT event closed it\n");
1370                         goto close_and_handled;
1371                 }
1372
1373                 n = lws_client_socket_service(context, wsi, pollfd);
1374                 if (n)
1375                         return 1;
1376                 goto handled;
1377 #endif
1378         }
1379
1380         n = 0;
1381         goto handled;
1382
1383 close_and_handled:
1384         lwsl_debug("%p: Close and handled\n", wsi);
1385         lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
1386         /*
1387          * pollfd may point to something else after the close
1388          * due to pollfd swapping scheme on delete on some platforms
1389          * we can't clear revents now because it'd be the wrong guy's revents
1390          */
1391         return 1;
1392
1393 handled:
1394         pollfd->revents = 0;
1395         return n;
1396 }
1397
1398 LWS_VISIBLE int
1399 lws_service_fd(struct lws_context *context, struct lws_pollfd *pollfd)
1400 {
1401         return lws_service_fd_tsi(context, pollfd, 0);
1402 }
1403
1404 LWS_VISIBLE int
1405 lws_service(struct lws_context *context, int timeout_ms)
1406 {
1407         return lws_plat_service(context, timeout_ms);
1408 }
1409
1410 LWS_VISIBLE int
1411 lws_service_tsi(struct lws_context *context, int timeout_ms, int tsi)
1412 {
1413         return _lws_plat_service_tsi(context, timeout_ms, tsi);
1414 }
1415