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