2 * libwebsockets - small server side websockets and web server implementation
4 * Copyright (C) 2010-2015 Andy Green <andy@warmcat.com>
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.
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.
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,
22 #include "private-libwebsockets.h"
25 lws_calllback_as_writeable(struct lws *wsi)
27 struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];
30 lws_stats_atomic_bump(wsi->context, pt, LWSSTATS_C_WRITEABLE_CB, 1);
31 #if defined(LWS_WITH_STATS)
33 uint64_t ul = time_in_microseconds() - wsi->active_writable_req_us;
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;
43 n = LWS_CALLBACK_RAW_WRITEABLE;
45 case LWSCM_RAW_FILEDESC:
46 n = LWS_CALLBACK_RAW_WRITEABLE_FILE;
49 n = LWS_CALLBACK_CLIENT_WRITEABLE;
51 case LWSCM_WSCL_ISSUE_HTTP_BODY:
52 n = LWS_CALLBACK_CLIENT_HTTP_WRITEABLE;
54 case LWSCM_WS_SERVING:
55 n = LWS_CALLBACK_SERVER_WRITEABLE;
58 n = LWS_CALLBACK_HTTP_WRITEABLE;
61 lwsl_debug("%s: %p (user=%p)\n", __func__, wsi, wsi->user_space);
62 return user_callback_handle_rxflow(wsi->protocol->callback,
63 wsi, (enum lws_callback_reasons) n,
64 wsi->user_space, NULL, 0);
68 lws_handle_POLLOUT_event(struct lws *wsi, struct lws_pollfd *pollfd)
70 int write_type = LWS_WRITE_PONG;
71 struct lws_tokens eff_buf;
77 //lwsl_err("%s: %p\n", __func__, wsi);
79 wsi->leave_pollout_active = 0;
80 wsi->handling_pollout = 1;
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.
88 * user callback is lowest priority to get these notifications
89 * actually, since other pending things cannot be disordered
92 /* Priority 1: pending truncated sends are incomplete ws fragments
93 * If anything else sent first the protocol would be
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__);
102 /* leave POLLOUT active either way */
105 if (wsi->state == LWSS_FLUSHING_STORED_SEND_BEFORE_CLOSE) {
106 wsi->socket_is_permanently_unusable = 1;
107 goto bail_die; /* retry closing now */
110 if (wsi->mode == LWSCM_WSCL_ISSUE_HTTP_BODY)
115 /* Priority 2: protocol packets
118 lwsl_info("servicing pps %d\n", 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);
127 wsi->pps = LWS_PPS_NONE;
128 lws_rx_flow_control(wsi, 1);
130 goto bail_ok; /* leave POLLOUT active */
138 if (lws_change_pollfd(wsi, LWS_POLLOUT, 0)) {
139 lwsl_info("failed at set pollfd\n");
142 goto user_service_go_again;
146 /* Priority 3: pending control packets (pong or close)
148 if ((wsi->state == LWSS_ESTABLISHED &&
149 wsi->u.ws.ping_pending_flag) ||
150 (wsi->state == LWSS_RETURNED_CLOSE_ALREADY &&
151 wsi->u.ws.payload_is_close)) {
153 if (wsi->u.ws.payload_is_close)
154 write_type = LWS_WRITE_CLOSE;
156 n = lws_write(wsi, &wsi->u.ws.ping_payload_buf[LWS_PRE],
157 wsi->u.ws.ping_payload_len, write_type);
161 /* well he is sent, mark him done */
162 wsi->u.ws.ping_pending_flag = 0;
163 if (wsi->u.ws.payload_is_close)
164 /* oh... a close frame was it... then we are done */
167 /* otherwise for PING, leave POLLOUT active either way */
171 if (wsi->state == LWSS_ESTABLISHED &&
172 !wsi->socket_is_permanently_unusable &&
173 wsi->u.ws.send_check_ping) {
175 lwsl_info("issuing ping on wsi %p\n", wsi);
176 wsi->u.ws.send_check_ping = 0;
177 n = lws_write(wsi, &wsi->u.ws.ping_payload_buf[LWS_PRE],
183 * we apparently were able to send the PING in a reasonable time
184 * now reset the clock on our peer to be able to send the
185 * PONG in a reasonable time.
188 lws_set_timeout(wsi, PENDING_TIMEOUT_WS_PONG_CHECK_GET_PONG,
189 wsi->context->timeout_secs);
194 /* Priority 4: if we are closing, not allowed to send more data frags
195 * which means user callback or tx ext flush banned now
197 if (wsi->state == LWSS_RETURNED_CLOSE_ALREADY)
200 /* Priority 5: Tx path extension with more to send
202 * These are handled as new fragments each time around
203 * So while we must block new writeable callback to enforce
204 * payload ordering, but since they are always complete
205 * fragments control packets can interleave OK.
207 if (wsi->state == LWSS_ESTABLISHED && wsi->u.ws.tx_draining_ext) {
208 lwsl_ext("SERVICING TX EXT DRAINING\n");
209 if (lws_write(wsi, NULL, 0, LWS_WRITE_CONTINUATION) < 0)
211 /* leave POLLOUT active */
215 /* Priority 6: user can get the callback
217 m = lws_ext_cb_active(wsi, LWS_EXT_CB_IS_WRITEABLE, NULL, 0);
220 #ifndef LWS_NO_EXTENSIONS
221 if (!wsi->extension_data_pending)
225 * check in on the active extensions, see if they
226 * had pending stuff to spill... they need to get the
227 * first look-in otherwise sequence will be disordered
229 * NULL, zero-length eff_buf means just spill pending
233 if (wsi->mode == LWSCM_RAW || wsi->mode == LWSCM_RAW_FILEDESC)
237 /* default to nobody has more to spill */
240 eff_buf.token = NULL;
241 eff_buf.token_len = 0;
243 /* give every extension a chance to spill */
245 m = lws_ext_cb_active(wsi,
246 LWS_EXT_CB_PACKET_TX_PRESEND,
249 lwsl_err("ext reports fatal error\n");
254 * at least one extension told us he has more
255 * to spill, so we will go around again after
259 /* assuming they gave us something to send, send it */
261 if (eff_buf.token_len) {
262 n = lws_issue_raw(wsi, (unsigned char *)eff_buf.token,
265 lwsl_info("closing from POLLOUT spill\n");
269 * Keep amount spilled small to minimize chance of this
271 if (n != eff_buf.token_len) {
272 lwsl_err("Unable to spill ext %d vs %d\n",
273 eff_buf.token_len, n);
279 /* no extension has more to spill */
285 * There's more to spill from an extension, but we just sent
286 * something... did that leave the pipe choked?
289 if (!lws_send_pipe_choked(wsi))
290 /* no we could add more */
293 lwsl_info("choked in POLLOUT service\n");
296 * Yes, he's choked. Leave the POLLOUT masked on so we will
297 * come back here when he is unchoked. Don't call the user
298 * callback to enforce ordering of spilling, he'll get called
299 * when we come back here and there's nothing more to spill.
304 #ifndef LWS_NO_EXTENSIONS
305 wsi->extension_data_pending = 0;
311 int eff = wsi->leave_pollout_active;
314 if (lws_change_pollfd(wsi, LWS_POLLOUT, 0)) {
315 lwsl_info("failed at set pollfd\n");
319 wsi->handling_pollout = 0;
321 /* cannot get leave_pollout_active set after the above */
323 if (!eff && wsi->leave_pollout_active)
324 /* got set inbetween sampling eff and clearing
325 * handling_pollout, force POLLOUT on */
326 lws_calllback_as_writeable(wsi);
328 wsi->leave_pollout_active = 0;
331 if (wsi->mode != LWSCM_WSCL_ISSUE_HTTP_BODY &&
332 !wsi->hdr_parsing_completed)
337 user_service_go_again:
342 * we are the 'network wsi' for potentially many muxed child wsi with
343 * no network connection of their own, who have to use us for all their
344 * network actions. So we use a round-robin scheme to share out the
345 * POLLOUT notifications to our children.
347 * But because any child could exhaust the socket's ability to take
348 * writes, we can only let one child get notified each time.
350 * In addition children may be closed / deleted / added between POLLOUT
351 * notifications, so we can't hold pointers
354 if (wsi->mode != LWSCM_HTTP2_SERVING) {
355 lwsl_info("%s: non http2\n", __func__);
359 wsi->u.http2.requested_POLLOUT = 0;
360 if (!wsi->u.http2.initialized) {
361 lwsl_info("pollout on uninitialized http2 conn\n");
365 lwsl_info("%s: doing children\n", __func__);
369 wsi2 = wsi2->u.http2.next_child_wsi;
370 lwsl_info("%s: child %p\n", __func__, wsi2);
373 if (!wsi2->u.http2.requested_POLLOUT)
375 wsi2->u.http2.requested_POLLOUT = 0;
376 if (lws_calllback_as_writeable(wsi2)) {
377 lwsl_debug("Closing POLLOUT child\n");
378 lws_close_free_wsi(wsi2, LWS_CLOSE_STATUS_NOSTATUS);
381 } while (wsi2 != NULL && !lws_send_pipe_choked(wsi));
383 lwsl_info("%s: completed\n", __func__);
388 wsi->handling_pollout = 0;
389 wsi->leave_pollout_active = 0;
391 return lws_calllback_as_writeable(wsi);
394 * since these don't disable the POLLOUT, they are always doing the
395 * right thing for leave_pollout_active whether it was set or not.
399 wsi->handling_pollout = 0;
400 wsi->leave_pollout_active = 0;
405 wsi->handling_pollout = 0;
406 wsi->leave_pollout_active = 0;
412 lws_service_timeout_check(struct lws *wsi, unsigned int sec)
415 struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];
422 * if extensions want in on it (eg, we are a mux parent)
423 * give them a chance to service child timeouts
425 if (lws_ext_cb_active(wsi, LWS_EXT_CB_1HZ, NULL, sec) < 0)
428 if (!wsi->pending_timeout)
432 * if we went beyond the allowed time, kill the
435 if ((time_t)sec > wsi->pending_timeout_limit) {
437 if (wsi->desc.sockfd != LWS_SOCK_INVALID && wsi->position_in_fds_table >= 0)
438 n = pt->fds[wsi->position_in_fds_table].events;
440 lws_stats_atomic_bump(wsi->context, pt, LWSSTATS_C_TIMEOUTS, 1);
442 /* no need to log normal idle keepalive timeout */
443 if (wsi->pending_timeout != PENDING_TIMEOUT_HTTP_KEEPALIVE_IDLE)
444 lwsl_notice("wsi %p: TIMEDOUT WAITING on %d (did hdr %d, ah %p, wl %d, pfd events %d) %llu vs %llu\n",
445 (void *)wsi, wsi->pending_timeout,
446 wsi->hdr_parsing_completed, wsi->u.hdr.ah,
447 pt->ah_wait_list_length, n, (unsigned long long)sec, (unsigned long long)wsi->pending_timeout_limit);
450 * Since he failed a timeout, he already had a chance to do
451 * something and was unable to... that includes situations like
452 * half closed connections. So process this "failed timeout"
453 * close as a violent death and don't try to do protocol
454 * cleanup like flush partials.
456 wsi->socket_is_permanently_unusable = 1;
457 if (wsi->mode == LWSCM_WSCL_WAITING_SSL)
458 wsi->vhost->protocols[0].callback(wsi,
459 LWS_CALLBACK_CLIENT_CONNECTION_ERROR,
460 wsi->user_space, (void *)"Timed out waiting SSL", 21);
462 lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
470 int lws_rxflow_cache(struct lws *wsi, unsigned char *buf, int n, int len)
472 /* his RX is flowcontrolled, don't send remaining now */
473 if (wsi->rxflow_buffer) {
474 /* rxflow while we were spilling prev rxflow */
475 lwsl_info("stalling in existing rxflow buf\n");
479 /* a new rxflow, buffer it and warn caller */
480 lwsl_info("new rxflow input buffer len %d\n", len - n);
481 wsi->rxflow_buffer = lws_malloc(len - n);
482 if (!wsi->rxflow_buffer)
484 wsi->rxflow_len = len - n;
486 memcpy(wsi->rxflow_buffer, buf + n, len - n);
491 /* this is used by the platform service code to stop us waiting for network
492 * activity in poll() when we have something that already needs service
495 LWS_VISIBLE LWS_EXTERN int
496 lws_service_adjust_timeout(struct lws_context *context, int timeout_ms, int tsi)
498 struct lws_context_per_thread *pt = &context->pt[tsi];
501 /* Figure out if we really want to wait in poll()
502 * We only need to wait if really nothing already to do and we have
503 * to wait for something from network
506 /* 1) if we know we are draining rx ext, do not wait in poll */
507 if (pt->rx_draining_ext_list)
510 #ifdef LWS_OPENSSL_SUPPORT
511 /* 2) if we know we have non-network pending data, do not wait in poll */
512 if (lws_ssl_anybody_has_buffered_read_tsi(context, tsi)) {
513 lwsl_info("ssl buffered read\n");
518 /* 3) if any ah has pending rx, do not wait in poll */
519 for (n = 0; n < context->max_http_header_pool; n++)
520 if (pt->ah_pool[n].rxpos != pt->ah_pool[n].rxlen) {
521 /* any ah with pending rx must be attached to someone */
522 if (!pt->ah_pool[n].wsi) {
523 lwsl_err("%s: assert: no wsi attached to ah\n", __func__);
533 * guys that need POLLIN service again without waiting for network action
534 * can force POLLIN here if not flowcontrolled, so they will get service.
536 * Return nonzero if anybody got their POLLIN faked
539 lws_service_flag_pending(struct lws_context *context, int tsi)
541 struct lws_context_per_thread *pt = &context->pt[tsi];
542 #ifdef LWS_OPENSSL_SUPPORT
543 struct lws *wsi_next;
552 * 1) For all guys with already-available ext data to drain, if they are
553 * not flowcontrolled, fake their POLLIN status
555 wsi = pt->rx_draining_ext_list;
557 pt->fds[wsi->position_in_fds_table].revents |=
558 pt->fds[wsi->position_in_fds_table].events & LWS_POLLIN;
559 if (pt->fds[wsi->position_in_fds_table].revents & LWS_POLLIN) {
563 wsi = wsi->u.ws.rx_draining_ext_list;
566 #ifdef LWS_OPENSSL_SUPPORT
568 * 2) For all guys with buffered SSL read data already saved up, if they
569 * are not flowcontrolled, fake their POLLIN status so they'll get
570 * service to use up the buffered incoming data, even though their
571 * network socket may have nothing
573 wsi = pt->pending_read_list;
575 wsi_next = wsi->pending_read_list_next;
576 pt->fds[wsi->position_in_fds_table].revents |=
577 pt->fds[wsi->position_in_fds_table].events & LWS_POLLIN;
578 if (pt->fds[wsi->position_in_fds_table].revents & LWS_POLLIN) {
581 * he's going to get serviced now, take him off the
582 * list of guys with buffered SSL. If he still has some
583 * at the end of the service, he'll get put back on the
586 lws_ssl_remove_wsi_from_buffered_list(wsi);
593 * 3) For any wsi who have an ah with pending RX who did not
594 * complete their current headers, and are not flowcontrolled,
595 * fake their POLLIN status so they will be able to drain the
596 * rx buffered in the ah
598 for (n = 0; n < context->max_http_header_pool; n++)
599 if (pt->ah_pool[n].rxpos != pt->ah_pool[n].rxlen &&
600 !pt->ah_pool[n].wsi->hdr_parsing_completed) {
601 pt->fds[pt->ah_pool[n].wsi->position_in_fds_table].revents |=
602 pt->fds[pt->ah_pool[n].wsi->position_in_fds_table].events &
604 if (pt->fds[pt->ah_pool[n].wsi->position_in_fds_table].revents &
612 #ifndef LWS_NO_CLIENT
615 lws_http_client_read(struct lws *wsi, char **buf, int *len)
619 rlen = lws_ssl_capable_read(wsi, (unsigned char *)*buf, *len);
622 /* allow the source to signal he has data again next time */
623 lws_change_pollfd(wsi, 0, LWS_POLLIN);
625 if (rlen == LWS_SSL_CAPABLE_ERROR) {
626 lwsl_notice("%s: SSL capable error\n", __func__);
637 wsi->client_rx_avail = 0;
640 * server may insist on transfer-encoding: chunked,
641 * so http client must deal with it
644 while (wsi->chunked && (wsi->chunk_parser != ELCP_CONTENT) && *len) {
645 switch (wsi->chunk_parser) {
647 if ((*buf)[0] == '\x0d') {
648 wsi->chunk_parser = ELCP_CR;
651 n = char_to_hex((*buf)[0]);
653 lwsl_debug("chunking failure\n");
656 wsi->chunk_remaining <<= 4;
657 wsi->chunk_remaining |= n;
660 if ((*buf)[0] != '\x0a') {
661 lwsl_debug("chunking failure\n");
664 wsi->chunk_parser = ELCP_CONTENT;
665 lwsl_info("chunk %d\n", wsi->chunk_remaining);
666 if (wsi->chunk_remaining)
668 lwsl_info("final chunk\n");
675 if ((*buf)[0] != '\x0d') {
676 lwsl_debug("chunking failure\n");
681 wsi->chunk_parser = ELCP_POST_LF;
685 if ((*buf)[0] != '\x0a')
688 wsi->chunk_parser = ELCP_HEX;
689 wsi->chunk_remaining = 0;
696 if (wsi->chunked && !wsi->chunk_remaining)
699 if (wsi->u.http.content_remain &&
700 (int)wsi->u.http.content_remain < *len)
701 n = wsi->u.http.content_remain;
705 if (wsi->chunked && wsi->chunk_remaining &&
706 wsi->chunk_remaining < n)
707 n = wsi->chunk_remaining;
709 #ifdef LWS_WITH_HTTP_PROXY
711 if (wsi->perform_rewrite)
712 lws_rewrite_parse(wsi->rw, (unsigned char *)*buf, n);
715 if (user_callback_handle_rxflow(wsi->protocol->callback,
716 wsi, LWS_CALLBACK_RECEIVE_CLIENT_HTTP_READ,
717 wsi->user_space, *buf, n)) {
718 lwsl_debug("%s: LWS_CALLBACK_RECEIVE_CLIENT_HTTP_READ returned -1\n", __func__);
723 if (wsi->chunked && wsi->chunk_remaining) {
725 wsi->chunk_remaining -= n;
729 if (wsi->chunked && !wsi->chunk_remaining)
730 wsi->chunk_parser = ELCP_POST_CR;
732 if (wsi->chunked && *len)
738 /* if we know the content length, decrement the content remaining */
739 if (wsi->u.http.content_length > 0)
740 wsi->u.http.content_remain -= n;
742 if (wsi->u.http.content_remain || !wsi->u.http.content_length)
746 if (user_callback_handle_rxflow(wsi->protocol->callback,
747 wsi, LWS_CALLBACK_COMPLETED_CLIENT_HTTP,
748 wsi->user_space, NULL, 0)) {
749 lwsl_debug("Completed call returned -1\n");
753 if (lws_http_transaction_completed_client(wsi)) {
754 lwsl_notice("%s: transaction completed says -1\n", __func__);
763 lws_is_ws_with_ext(struct lws *wsi)
765 #if defined(LWS_NO_EXTENSIONS)
768 return wsi->state == LWSS_ESTABLISHED &&
769 !!wsi->count_act_ext;
774 lws_service_fd_tsi(struct lws_context *context, struct lws_pollfd *pollfd, int tsi)
776 struct lws_context_per_thread *pt = &context->pt[tsi];
777 lws_sockfd_type our_fd = 0, tmp_fd;
778 struct lws_tokens eff_buf;
779 unsigned int pending = 0;
780 struct lws *wsi, *wsi1;
781 char draining_flow = 0;
787 if (!context->protocol_init_done)
788 lws_protocol_init(context);
793 * handle case that system time was uninitialized when lws started
794 * at boot, and got initialized a little later
796 if (context->time_up < 1464083026 && now > 1464083026)
797 context->time_up = now;
799 /* TODO: if using libev, we should probably use timeout watchers... */
800 if (context->last_timeout_check_s != now) {
801 context->last_timeout_check_s = now;
803 #if defined(LWS_WITH_STATS)
804 if (!tsi && now - context->last_dump > 10) {
805 lws_stats_log_dump(context);
806 context->last_dump = now;
810 lws_plat_service_periodic(context);
812 /* retire unused deprecated context */
813 #if !defined(LWS_PLAT_OPTEE) && !defined(LWS_WITH_ESP32)
814 #if LWS_POSIX && !defined(_WIN32)
815 if (context->deprecated && !context->count_wsi_allocated) {
816 lwsl_notice("%s: ending deprecated context\n", __func__);
817 kill(getpid(), SIGINT);
822 /* global timeout check once per second */
827 wsi = context->pt[tsi].timeout_list;
829 /* we have to take copies, because he may be deleted */
830 wsi1 = wsi->timeout_list;
831 tmp_fd = wsi->desc.sockfd;
832 if (lws_service_timeout_check(wsi, (unsigned int)now)) {
833 /* he did time out... */
834 if (tmp_fd == our_fd)
835 /* it was the guy we came to service! */
837 /* he's gone, no need to mark as handled */
842 lws_cgi_kill_terminated(pt);
848 for (n = 0; n < context->count_threads; n++)
849 p += sprintf(p, " %7lu (%5d), ",
850 context->pt[n].count_conns,
851 context->pt[n].fds_count);
853 lwsl_notice("load: %s\n", s);
859 * at intervals, check for ws connections needing ping-pong checks
862 if (context->ws_ping_pong_interval &&
863 context->last_ws_ping_pong_check_s < now + 10) {
864 struct lws_vhost *vh = context->vhost_list;
865 context->last_ws_ping_pong_check_s = now;
868 for (n = 0; n < vh->count_protocols; n++) {
869 wsi = vh->same_vh_protocol_list[n];
872 if (wsi->state == LWSS_ESTABLISHED &&
873 !wsi->socket_is_permanently_unusable &&
874 !wsi->u.ws.send_check_ping &&
875 wsi->u.ws.time_next_ping_check &&
876 wsi->u.ws.time_next_ping_check < now) {
878 lwsl_info("requesting ping-pong on wsi %p\n", wsi);
879 wsi->u.ws.send_check_ping = 1;
880 lws_set_timeout(wsi, PENDING_TIMEOUT_WS_PONG_CHECK_SEND_PING,
881 context->timeout_secs);
882 lws_callback_on_writable(wsi);
883 wsi->u.ws.time_next_ping_check = now +
884 wsi->context->ws_ping_pong_interval;
886 wsi = wsi->same_vh_protocol_next;
893 /* the socket we came to service timed out, nothing to do */
897 /* just here for timeout management? */
901 /* no, here to service a socket descriptor */
902 wsi = wsi_from_fd(context, pollfd->fd);
904 /* not lws connection ... leave revents alone and return */
908 * so that caller can tell we handled, past here we need to
909 * zero down pollfd->revents after handling
913 /* handle session socket closed */
915 if ((!(pollfd->revents & pollfd->events & LWS_POLLIN)) &&
916 (pollfd->revents & LWS_POLLHUP)) {
917 wsi->socket_is_permanently_unusable = 1;
918 lwsl_debug("Session Socket %p (fd=%d) dead\n",
919 (void *)wsi, pollfd->fd);
921 goto close_and_handled;
925 if (pollfd->revents & LWS_POLLOUT)
926 wsi->sock_send_blocking = FALSE;
931 // lwsl_debug("fd=%d, revents=%d, mode=%d, state=%d\n", pollfd->fd, pollfd->revents, (int)wsi->mode, (int)wsi->state);
932 if (pollfd->revents & LWS_POLLHUP) {
933 lwsl_debug("pollhup\n");
934 wsi->socket_is_permanently_unusable = 1;
935 goto close_and_handled;
939 #ifdef LWS_OPENSSL_SUPPORT
940 if ((wsi->state == LWSS_SHUTDOWN) && lws_is_ssl(wsi) && wsi->ssl)
942 n = SSL_shutdown(wsi->ssl);
943 lwsl_debug("SSL_shutdown=%d for fd %d\n", n, wsi->desc.sockfd);
946 n = shutdown(wsi->desc.sockfd, SHUT_WR);
947 goto close_and_handled;
951 lws_change_pollfd(wsi, LWS_POLLOUT, LWS_POLLIN);
957 int shutdown_error = SSL_get_error(wsi->ssl, n);
958 lwsl_debug("SSL_shutdown returned %d, SSL_get_error: %d\n", n, shutdown_error);
959 if (shutdown_error == SSL_ERROR_WANT_READ) {
960 lws_change_pollfd(wsi, LWS_POLLOUT, LWS_POLLIN);
963 } else if (shutdown_error == SSL_ERROR_WANT_WRITE) {
964 lws_change_pollfd(wsi, LWS_POLLOUT, LWS_POLLOUT);
969 // actual error occurred, just close the connection
970 n = shutdown(wsi->desc.sockfd, SHUT_WR);
971 goto close_and_handled;
976 /* okay, what we came here to do... */
979 case LWSCM_HTTP_SERVING:
980 case LWSCM_HTTP_CLIENT:
981 case LWSCM_HTTP_SERVING_ACCEPTED:
982 case LWSCM_SERVER_LISTENER:
983 case LWSCM_SSL_ACK_PENDING:
984 case LWSCM_SSL_ACK_PENDING_RAW:
985 if (wsi->state == LWSS_CLIENT_HTTP_ESTABLISHED)
989 if (wsi->cgi && (pollfd->revents & LWS_POLLOUT)) {
990 n = lws_handle_POLLOUT_event(wsi, pollfd);
992 goto close_and_handled;
998 n = lws_server_socket_service(context, wsi, pollfd);
999 if (n) /* closed by above */
1003 case LWSCM_RAW_FILEDESC:
1005 if (pollfd->revents & LWS_POLLOUT) {
1006 n = lws_calllback_as_writeable(wsi);
1007 if (lws_change_pollfd(wsi, LWS_POLLOUT, 0)) {
1008 lwsl_info("failed at set pollfd\n");
1012 goto close_and_handled;
1014 n = LWS_CALLBACK_RAW_RX;
1015 if (wsi->mode == LWSCM_RAW_FILEDESC)
1016 n = LWS_CALLBACK_RAW_RX_FILE;
1018 if (pollfd->revents & LWS_POLLIN) {
1019 if (user_callback_handle_rxflow(
1020 wsi->protocol->callback,
1022 wsi->user_space, NULL, 0)) {
1023 lwsl_debug("raw rx callback closed it\n");
1024 goto close_and_handled;
1028 if (pollfd->revents & LWS_POLLHUP)
1029 goto close_and_handled;
1033 case LWSCM_WS_SERVING:
1034 case LWSCM_WS_CLIENT:
1035 case LWSCM_HTTP2_SERVING:
1036 case LWSCM_HTTP_CLIENT_ACCEPTED:
1038 /* 1: something requested a callback when it was OK to write */
1040 if ((pollfd->revents & LWS_POLLOUT) &&
1041 ((wsi->state == LWSS_ESTABLISHED ||
1042 wsi->state == LWSS_HTTP2_ESTABLISHED ||
1043 wsi->state == LWSS_HTTP2_ESTABLISHED_PRE_SETTINGS ||
1044 wsi->state == LWSS_RETURNED_CLOSE_ALREADY ||
1045 wsi->state == LWSS_FLUSHING_STORED_SEND_BEFORE_CLOSE)) &&
1046 lws_handle_POLLOUT_event(wsi, pollfd)) {
1047 if (wsi->state == LWSS_RETURNED_CLOSE_ALREADY)
1048 wsi->state = LWSS_FLUSHING_STORED_SEND_BEFORE_CLOSE;
1049 lwsl_info("lws_service_fd: closing\n");
1050 goto close_and_handled;
1053 if (wsi->state == LWSS_RETURNED_CLOSE_ALREADY ||
1054 wsi->state == LWSS_AWAITING_CLOSE_ACK) {
1056 * we stopped caring about anything except control
1057 * packets. Force flow control off, defeat tx
1060 lws_rx_flow_control(wsi, 1);
1061 wsi->u.ws.tx_draining_ext = 0;
1064 if (wsi->u.ws.tx_draining_ext)
1065 /* we cannot deal with new RX until the TX ext
1066 * path has been drained. It's because new
1067 * rx will, eg, crap on the wsi rx buf that
1068 * may be needed to retain state.
1070 * TX ext drain path MUST go through event loop
1071 * to avoid blocking.
1075 if (!(wsi->rxflow_change_to & LWS_RXFLOW_ALLOW))
1076 /* We cannot deal with any kind of new RX
1077 * because we are RX-flowcontrolled.
1081 /* 2: RX Extension needs to be drained
1084 if (wsi->state == LWSS_ESTABLISHED &&
1085 wsi->u.ws.rx_draining_ext) {
1087 lwsl_ext("%s: RX EXT DRAINING: Service\n", __func__);
1088 #ifndef LWS_NO_CLIENT
1089 if (wsi->mode == LWSCM_WS_CLIENT) {
1090 n = lws_client_rx_sm(wsi, 0);
1096 n = lws_rx_sm(wsi, 0);
1101 if (wsi->u.ws.rx_draining_ext)
1103 * We have RX EXT content to drain, but can't do it
1104 * right now. That means we cannot do anything lower
1109 /* 3: RX Flowcontrol buffer needs to be drained
1112 if (wsi->rxflow_buffer) {
1113 lwsl_info("draining rxflow (len %d)\n",
1114 wsi->rxflow_len - wsi->rxflow_pos
1116 /* well, drain it */
1117 eff_buf.token = (char *)wsi->rxflow_buffer +
1119 eff_buf.token_len = wsi->rxflow_len - wsi->rxflow_pos;
1124 /* 4: any incoming (or ah-stashed incoming rx) data ready?
1125 * notice if rx flow going off raced poll(), rx flow wins
1128 if (!(pollfd->revents & pollfd->events & LWS_POLLIN))
1132 /* all the union members start with hdr, so even in ws mode
1133 * we can deal with the ah via u.hdr
1135 if (wsi->u.hdr.ah) {
1136 lwsl_info("%s: %p: inherited ah rx\n", __func__, wsi);
1137 eff_buf.token_len = wsi->u.hdr.ah->rxlen -
1138 wsi->u.hdr.ah->rxpos;
1139 eff_buf.token = (char *)wsi->u.hdr.ah->rx +
1140 wsi->u.hdr.ah->rxpos;
1142 if (wsi->mode != LWSCM_HTTP_CLIENT_ACCEPTED) {
1144 * extension may not consume everything (eg, pmd may be constrained
1145 * as to what it can output...) has to go in per-wsi rx buf area.
1146 * Otherwise in large temp serv_buf area.
1148 eff_buf.token = (char *)pt->serv_buf;
1149 if (lws_is_ws_with_ext(wsi)) {
1150 eff_buf.token_len = wsi->u.ws.rx_ubuf_alloc;
1152 eff_buf.token_len = context->pt_serv_buf_size;
1155 if (eff_buf.token_len > context->pt_serv_buf_size)
1156 eff_buf.token_len = context->pt_serv_buf_size;
1158 eff_buf.token_len = lws_ssl_capable_read(wsi,
1159 (unsigned char *)eff_buf.token, pending ? pending :
1161 switch (eff_buf.token_len) {
1163 lwsl_info("%s: zero length read\n", __func__);
1164 goto close_and_handled;
1165 case LWS_SSL_CAPABLE_MORE_SERVICE:
1166 lwsl_info("SSL Capable more service\n");
1169 case LWS_SSL_CAPABLE_ERROR:
1170 lwsl_info("Closing when error\n");
1171 goto close_and_handled;
1173 // lwsl_notice("Actual RX %d\n", eff_buf.token_len);
1178 #ifndef LWS_NO_CLIENT
1179 if (wsi->mode == LWSCM_HTTP_CLIENT_ACCEPTED &&
1180 !wsi->told_user_closed) {
1183 * In SSL mode we get POLLIN notification about
1184 * encrypted data in.
1186 * But that is not necessarily related to decrypted
1187 * data out becoming available; in may need to perform
1188 * other in or out before that happens.
1190 * simply mark ourselves as having readable data
1191 * and turn off our POLLIN
1193 wsi->client_rx_avail = 1;
1194 lws_change_pollfd(wsi, LWS_POLLIN, 0);
1196 /* let user code know, he'll usually ask for writeable
1197 * callback and drain / re-enable it there
1199 if (user_callback_handle_rxflow(
1200 wsi->protocol->callback,
1201 wsi, LWS_CALLBACK_RECEIVE_CLIENT_HTTP,
1202 wsi->user_space, NULL, 0)) {
1203 lwsl_notice("LWS_CALLBACK_RECEIVE_CLIENT_HTTP closed it\n");
1204 goto close_and_handled;
1209 * give any active extensions a chance to munge the buffer
1210 * before parse. We pass in a pointer to an lws_tokens struct
1211 * prepared with the default buffer and content length that's in
1212 * there. Rather than rewrite the default buffer, extensions
1213 * that expect to grow the buffer can adapt .token to
1214 * point to their own per-connection buffer in the extension
1215 * user allocation. By default with no extensions or no
1216 * extension callback handling, just the normal input buffer is
1217 * used then so it is efficient.
1222 m = lws_ext_cb_active(wsi, LWS_EXT_CB_PACKET_RX_PREPARSE,
1225 goto close_and_handled;
1229 /* service incoming data */
1231 if (eff_buf.token_len) {
1233 * if draining from rxflow buffer, not
1234 * critical to track what was used since at the
1235 * use it bumps wsi->rxflow_pos. If we come
1236 * around again it will pick up from where it
1239 // 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);
1241 n = lws_read(wsi, (unsigned char *)eff_buf.token,
1250 eff_buf.token = NULL;
1251 eff_buf.token_len = 0;
1254 if (wsi->u.hdr.ah) {
1255 lwsl_notice("%s: %p: detaching\n",
1257 /* show we used all the pending rx up */
1258 wsi->u.hdr.ah->rxpos = wsi->u.hdr.ah->rxlen;
1259 /* we can run the normal ah detach flow despite
1260 * being in ws union mode, since all union members
1262 lws_header_table_detach(wsi, 0);
1265 pending = lws_ssl_pending(wsi);
1267 if (lws_is_ws_with_ext(wsi))
1268 pending = pending > wsi->u.ws.rx_ubuf_alloc ?
1269 wsi->u.ws.rx_ubuf_alloc : pending;
1271 pending = pending > context->pt_serv_buf_size ?
1272 context->pt_serv_buf_size : pending;
1276 if (draining_flow && wsi->rxflow_buffer &&
1277 wsi->rxflow_pos == wsi->rxflow_len) {
1278 lwsl_info("flow buffer: drained\n");
1279 lws_free_set_NULL(wsi->rxflow_buffer);
1280 /* having drained the rxflow buffer, can rearm POLLIN */
1281 #ifdef LWS_NO_SERVER
1284 _lws_rx_flow_control(wsi);
1285 /* n ignored, needed for NO_SERVER case */
1290 case LWSCM_CGI: /* we exist to handle a cgi's stdin/out/err data...
1291 * do the callback on our master wsi
1294 struct lws_cgi_args args;
1296 if (wsi->cgi_channel >= LWS_STDOUT &&
1297 !(pollfd->revents & pollfd->events & LWS_POLLIN))
1299 if (wsi->cgi_channel == LWS_STDIN &&
1300 !(pollfd->revents & pollfd->events & LWS_POLLOUT))
1303 if (wsi->cgi_channel == LWS_STDIN)
1304 if (lws_change_pollfd(wsi, LWS_POLLOUT, 0)) {
1305 lwsl_info("failed at set pollfd\n");
1309 args.ch = wsi->cgi_channel;
1310 args.stdwsi = &wsi->parent->cgi->stdwsi[0];
1311 args.hdr_state = wsi->hdr_state;
1313 //lwsl_err("CGI LWS_STDOUT waiting wsi %p mode %d state %d\n",
1314 // wsi->parent, wsi->parent->mode, wsi->parent->state);
1316 if (user_callback_handle_rxflow(
1317 wsi->parent->protocol->callback,
1318 wsi->parent, LWS_CALLBACK_CGI,
1319 wsi->parent->user_space,
1327 #ifdef LWS_NO_CLIENT
1330 if ((pollfd->revents & LWS_POLLOUT) &&
1331 lws_handle_POLLOUT_event(wsi, pollfd)) {
1332 lwsl_debug("POLLOUT event closed it\n");
1333 goto close_and_handled;
1336 n = lws_client_socket_service(context, wsi, pollfd);
1347 lwsl_debug("%p: Close and handled\n", wsi);
1348 lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
1350 * pollfd may point to something else after the close
1351 * due to pollfd swapping scheme on delete on some platforms
1352 * we can't clear revents now because it'd be the wrong guy's revents
1357 pollfd->revents = 0;
1362 lws_service_fd(struct lws_context *context, struct lws_pollfd *pollfd)
1364 return lws_service_fd_tsi(context, pollfd, 0);
1368 lws_service(struct lws_context *context, int timeout_ms)
1370 return lws_plat_service(context, timeout_ms);
1374 lws_service_tsi(struct lws_context *context, int timeout_ms, int tsi)
1376 return _lws_plat_service_tsi(context, timeout_ms, tsi);