lib/output.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_0405_frame_mask_generate(struct lws *wsi)
  26 {
  27 #if 0
  28         wsi->u.ws.mask[0] = 0;
  29         wsi->u.ws.mask[1] = 0;
  30         wsi->u.ws.mask[2] = 0;
  31         wsi->u.ws.mask[3] = 0;
  32 #else
  33         int n;
  34         /* fetch the per-frame nonce */
  35
  36         n = lws_get_random(lws_get_context(wsi), wsi->u.ws.mask, 4);
  37         if (n != 4) {
  38                 lwsl_parser("Unable to read from random device %s %d\n",
  39                             SYSTEM_RANDOM_FILEPATH, n);
  40                 return 1;
  41         }
  42 #endif
  43         /* start masking from first byte of masking key buffer */
  44         wsi->u.ws.mask_idx = 0;
  45
  46         return 0;
  47 }
  48
  49 #ifdef _DEBUG
  50
  51 LWS_VISIBLE void lwsl_hexdump(void *vbuf, size_t len)
  52 {
  53         unsigned char *buf = (unsigned char *)vbuf;
  54         unsigned int n, m, start;
  55         char line[80];
  56         char *p;
  57
  58         lwsl_parser("\n");
  59
  60         for (n = 0; n < len;) {
  61                 start = n;
  62                 p = line;
  63
  64                 p += sprintf(p, "%04X: ", start);
  65
  66                 for (m = 0; m < 16 && n < len; m++)
  67                         p += sprintf(p, "%02X ", buf[n++]);
  68                 while (m++ < 16)
  69                         p += sprintf(p, "   ");
  70
  71                 p += sprintf(p, "   ");
  72
  73                 for (m = 0; m < 16 && (start + m) < len; m++) {
  74                         if (buf[start + m] >= ' ' && buf[start + m] < 127)
  75                                 *p++ = buf[start + m];
  76                         else
  77                                 *p++ = '.';
  78                 }
  79                 while (m++ < 16)
  80                         *p++ = ' ';
  81
  82                 *p++ = '\n';
  83                 *p = '\0';
  84                 lwsl_debug("%s", line);
  85         }
  86         lwsl_debug("\n");
  87 }
  88
  89 #endif
  90
  91 /*
  92  * notice this returns number of bytes consumed, or -1
  93  */
  94
  95 int lws_issue_raw(struct lws *wsi, unsigned char *buf, size_t len)
  96 {
  97         struct lws_context *context = lws_get_context(wsi);
  98         size_t real_len = len;
  99         unsigned int n;
 100         int m;
 101
 102         if (!len)
 103                 return 0;
 104         /* just ignore sends after we cleared the truncation buffer */
 105         if (wsi->state == LWSS_FLUSHING_STORED_SEND_BEFORE_CLOSE &&
 106             !wsi->trunc_len)
 107                 return len;
 108
 109         if (wsi->trunc_len && (buf < wsi->trunc_alloc ||
 110             buf > (wsi->trunc_alloc + wsi->trunc_len + wsi->trunc_offset))) {
 111                 char dump[20];
 112                 strncpy(dump, (char *)buf, sizeof(dump) - 1);
 113                 dump[sizeof(dump) - 1] = '\0';
 114 #if defined(LWS_WITH_ESP8266)
 115                 lwsl_err("****** %p: Sending new %lu (%s), pending truncated ...\n",
 116                          wsi, (unsigned long)len, dump);
 117 #else
 118                 lwsl_err("****** %p: Sending new %lu (%s), pending truncated ...\n"
 119                          "       It's illegal to do an lws_write outside of\n"
 120                          "       the writable callback: fix your code",
 121                          wsi, (unsigned long)len, dump);
 122 #endif
 123                 assert(0);
 124
 125                 return -1;
 126         }
 127
 128         m = lws_ext_cb_active(wsi, LWS_EXT_CB_PACKET_TX_DO_SEND, &buf, len);
 129         if (m < 0)
 130                 return -1;
 131         if (m) /* handled */ {
 132                 n = m;
 133                 goto handle_truncated_send;
 134         }
 135
 136         if (!lws_socket_is_valid(wsi->desc.sockfd))
 137                 lwsl_warn("** error invalid sock but expected to send\n");
 138
 139         /* limit sending */
 140         if (wsi->protocol->tx_packet_size)
 141                 n = wsi->protocol->tx_packet_size;
 142         else {
 143                 n = wsi->protocol->rx_buffer_size;
 144                 if (!n)
 145                         n = context->pt_serv_buf_size;
 146         }
 147         n += LWS_PRE + 4;
 148         if (n > len)
 149                 n = len;
 150 #if defined(LWS_WITH_ESP8266)
 151         if (wsi->pending_send_completion) {
 152                 n = 0;
 153                 goto handle_truncated_send;
 154         }
 155 #endif
 156
 157         /* nope, send it on the socket directly */
 158         lws_latency_pre(context, wsi);
 159         n = lws_ssl_capable_write(wsi, buf, n);
 160         lws_latency(context, wsi, "send lws_issue_raw", n, n == len);
 161
 162         //lwsl_notice("lws_ssl_capable_write: %d\n", n);
 163
 164         switch (n) {
 165         case LWS_SSL_CAPABLE_ERROR:
 166                 /* we're going to close, let close know sends aren't possible */
 167                 wsi->socket_is_permanently_unusable = 1;
 168                 return -1;
 169         case LWS_SSL_CAPABLE_MORE_SERVICE:
 170                 /* nothing got sent, not fatal, retry the whole thing later */
 171                 n = 0;
 172                 break;
 173         }
 174
 175 handle_truncated_send:
 176         /*
 177          * we were already handling a truncated send?
 178          */
 179         if (wsi->trunc_len) {
 180                 lwsl_info("%p partial adv %d (vs %ld)\n", wsi, n, (long)real_len);
 181                 wsi->trunc_offset += n;
 182                 wsi->trunc_len -= n;
 183
 184                 if (!wsi->trunc_len) {
 185                         lwsl_info("***** %p partial send completed\n", wsi);
 186                         /* done with it, but don't free it */
 187                         n = real_len;
 188                         if (wsi->state == LWSS_FLUSHING_STORED_SEND_BEFORE_CLOSE) {
 189                                 lwsl_info("***** %p signalling to close now\n", wsi);
 190                                 return -1; /* retry closing now */
 191                         }
 192                 }
 193                 /* always callback on writeable */
 194                 lws_callback_on_writable(wsi);
 195
 196                 return n;
 197         }
 198
 199         if ((unsigned int)n == real_len)
 200                 /* what we just sent went out cleanly */
 201                 return n;
 202
 203         /*
 204          * Newly truncated send.  Buffer the remainder (it will get
 205          * first priority next time the socket is writable)
 206          */
 207         lwsl_debug("%p new partial sent %d from %lu total\n", wsi, n,
 208                     (unsigned long)real_len);
 209
 210         /*
 211          *  - if we still have a suitable malloc lying around, use it
 212          *  - or, if too small, reallocate it
 213          *  - or, if no buffer, create it
 214          */
 215         if (!wsi->trunc_alloc || real_len - n > wsi->trunc_alloc_len) {
 216                 lws_free(wsi->trunc_alloc);
 217
 218                 wsi->trunc_alloc_len = real_len - n;
 219                 wsi->trunc_alloc = lws_malloc(real_len - n);
 220                 if (!wsi->trunc_alloc) {
 221                         lwsl_err("truncated send: unable to malloc %lu\n",
 222                                  (unsigned long)(real_len - n));
 223                         return -1;
 224                 }
 225         }
 226         wsi->trunc_offset = 0;
 227         wsi->trunc_len = real_len - n;
 228         memcpy(wsi->trunc_alloc, buf + n, real_len - n);
 229
 230         /* since something buffered, force it to get another chance to send */
 231         lws_callback_on_writable(wsi);
 232
 233         return real_len;
 234 }
 235
 236 LWS_VISIBLE int lws_write(struct lws *wsi, unsigned char *buf, size_t len,
 237                           enum lws_write_protocol wp)
 238 {
 239         struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];
 240         int masked7 = (wsi->mode == LWSCM_WS_CLIENT);
 241         unsigned char is_masked_bit = 0;
 242         unsigned char *dropmask = NULL;
 243         struct lws_tokens eff_buf;
 244         int pre = 0, n;
 245         size_t orig_len = len;
 246
 247         if ((int)len < 0) {
 248                 lwsl_err("%s: suspicious len int %d, ulong %lu\n", __func__,
 249                                 (int)len, (unsigned long)len);
 250                 return -1;
 251         }
 252
 253 #ifdef LWS_WITH_ACCESS_LOG
 254         wsi->access_log.sent += len;
 255 #endif
 256         if (wsi->vhost)
 257                 wsi->vhost->conn_stats.tx += len;
 258
 259         if (wsi->state == LWSS_ESTABLISHED && wsi->u.ws.tx_draining_ext) {
 260                 /* remove us from the list */
 261                 struct lws **w = &pt->tx_draining_ext_list;
 262                 lwsl_debug("%s: TX EXT DRAINING: Remove from list\n", __func__);
 263                 wsi->u.ws.tx_draining_ext = 0;
 264                 /* remove us from context draining ext list */
 265                 while (*w) {
 266                         if (*w == wsi) {
 267                                 *w = wsi->u.ws.tx_draining_ext_list;
 268                                 break;
 269                         }
 270                         w = &((*w)->u.ws.tx_draining_ext_list);
 271                 }
 272                 wsi->u.ws.tx_draining_ext_list = NULL;
 273                 wp = (wsi->u.ws.tx_draining_stashed_wp & 0xc0) |
 274                                 LWS_WRITE_CONTINUATION;
 275
 276                 lwsl_ext("FORCED draining wp to 0x%02X\n", wp);
 277         }
 278
 279         lws_restart_ws_ping_pong_timer(wsi);
 280
 281         if (wp == LWS_WRITE_HTTP ||
 282             wp == LWS_WRITE_HTTP_FINAL ||
 283             wp == LWS_WRITE_HTTP_HEADERS)
 284                 goto send_raw;
 285
 286         /* if not in a state to send stuff, then just send nothing */
 287
 288         if (wsi->state != LWSS_ESTABLISHED &&
 289             ((wsi->state != LWSS_RETURNED_CLOSE_ALREADY &&
 290               wsi->state != LWSS_AWAITING_CLOSE_ACK) ||
 291                             wp != LWS_WRITE_CLOSE))
 292                 return 0;
 293
 294         /* if we are continuing a frame that already had its header done */
 295
 296         if (wsi->u.ws.inside_frame) {
 297                 lwsl_debug("INSIDE FRAME\n");
 298                 goto do_more_inside_frame;
 299         }
 300
 301         wsi->u.ws.clean_buffer = 1;
 302
 303         /*
 304          * give a chance to the extensions to modify payload
 305          * the extension may decide to produce unlimited payload erratically
 306          * (eg, compression extension), so we require only that if he produces
 307          * something, it will be a complete fragment of the length known at
 308          * the time (just the fragment length known), and if he has
 309          * more we will come back next time he is writeable and allow him to
 310          * produce more fragments until he's drained.
 311          *
 312          * This allows what is sent each time it is writeable to be limited to
 313          * a size that can be sent without partial sends or blocking, allows
 314          * interleaving of control frames and other connection service.
 315          */
 316         eff_buf.token = (char *)buf;
 317         eff_buf.token_len = len;
 318
 319         switch ((int)wp) {
 320         case LWS_WRITE_PING:
 321         case LWS_WRITE_PONG:
 322         case LWS_WRITE_CLOSE:
 323                 break;
 324         default:
 325                 n = lws_ext_cb_active(wsi, LWS_EXT_CB_PAYLOAD_TX, &eff_buf, wp);
 326                 if (n < 0)
 327                         return -1;
 328
 329                 if (n && eff_buf.token_len) {
 330                         /* extension requires further draining */
 331                         wsi->u.ws.tx_draining_ext = 1;
 332                         wsi->u.ws.tx_draining_ext_list = pt->tx_draining_ext_list;
 333                         pt->tx_draining_ext_list = wsi;
 334                         /* we must come back to do more */
 335                         lws_callback_on_writable(wsi);
 336                         /*
 337                          * keep a copy of the write type for the overall
 338                          * action that has provoked generation of these
 339                          * fragments, so the last guy can use its FIN state.
 340                          */
 341                         wsi->u.ws.tx_draining_stashed_wp = wp;
 342                         /* this is definitely not actually the last fragment
 343                          * because the extension asserted he has more coming
 344                          * So make sure this intermediate one doesn't go out
 345                          * with a FIN.
 346                          */
 347                         wp |= LWS_WRITE_NO_FIN;
 348                 }
 349
 350                 if (eff_buf.token_len && wsi->u.ws.stashed_write_pending) {
 351                         wsi->u.ws.stashed_write_pending = 0;
 352                         wp = (wp &0xc0) | (int)wsi->u.ws.stashed_write_type;
 353                 }
 354         }
 355
 356         /*
 357          * an extension did something we need to keep... for example, if
 358          * compression extension, it has already updated its state according
 359          * to this being issued
 360          */
 361         if ((char *)buf != eff_buf.token) {
 362                 /*
 363                  * ext might eat it, but no have anything to issue yet
 364                  * in that case we have to follow his lead, but stash and
 365                  * replace the write type that was lost here the first time.
 366                  */
 367                 if (len && !eff_buf.token_len) {
 368                         if (!wsi->u.ws.stashed_write_pending)
 369                                 wsi->u.ws.stashed_write_type = (char)wp & 0x3f;
 370                         wsi->u.ws.stashed_write_pending = 1;
 371                         return len;
 372                 }
 373                 /*
 374                  * extension recreated it:
 375                  * need to buffer this if not all sent
 376                  */
 377                 wsi->u.ws.clean_buffer = 0;
 378         }
 379
 380         buf = (unsigned char *)eff_buf.token;
 381         len = eff_buf.token_len;
 382
 383         switch (wsi->ietf_spec_revision) {
 384         case 13:
 385                 if (masked7) {
 386                         pre += 4;
 387                         dropmask = &buf[0 - pre];
 388                         is_masked_bit = 0x80;
 389                 }
 390
 391                 switch (wp & 0xf) {
 392                 case LWS_WRITE_TEXT:
 393                         n = LWSWSOPC_TEXT_FRAME;
 394                         break;
 395                 case LWS_WRITE_BINARY:
 396                         n = LWSWSOPC_BINARY_FRAME;
 397                         break;
 398                 case LWS_WRITE_CONTINUATION:
 399                         n = LWSWSOPC_CONTINUATION;
 400                         break;
 401
 402                 case LWS_WRITE_CLOSE:
 403                         n = LWSWSOPC_CLOSE;
 404                         break;
 405                 case LWS_WRITE_PING:
 406                         n = LWSWSOPC_PING;
 407                         break;
 408                 case LWS_WRITE_PONG:
 409                         n = LWSWSOPC_PONG;
 410                         break;
 411                 default:
 412                         lwsl_warn("lws_write: unknown write opc / wp\n");
 413                         return -1;
 414                 }
 415
 416                 if (!(wp & LWS_WRITE_NO_FIN))
 417                         n |= 1 << 7;
 418
 419                 if (len < 126) {
 420                         pre += 2;
 421                         buf[-pre] = n;
 422                         buf[-pre + 1] = (unsigned char)(len | is_masked_bit);
 423                 } else {
 424                         if (len < 65536) {
 425                                 pre += 4;
 426                                 buf[-pre] = n;
 427                                 buf[-pre + 1] = 126 | is_masked_bit;
 428                                 buf[-pre + 2] = (unsigned char)(len >> 8);
 429                                 buf[-pre + 3] = (unsigned char)len;
 430                         } else {
 431                                 pre += 10;
 432                                 buf[-pre] = n;
 433                                 buf[-pre + 1] = 127 | is_masked_bit;
 434 #if defined __LP64__
 435                                         buf[-pre + 2] = (len >> 56) & 0x7f;
 436                                         buf[-pre + 3] = len >> 48;
 437                                         buf[-pre + 4] = len >> 40;
 438                                         buf[-pre + 5] = len >> 32;
 439 #else
 440                                         buf[-pre + 2] = 0;
 441                                         buf[-pre + 3] = 0;
 442                                         buf[-pre + 4] = 0;
 443                                         buf[-pre + 5] = 0;
 444 #endif
 445                                 buf[-pre + 6] = (unsigned char)(len >> 24);
 446                                 buf[-pre + 7] = (unsigned char)(len >> 16);
 447                                 buf[-pre + 8] = (unsigned char)(len >> 8);
 448                                 buf[-pre + 9] = (unsigned char)len;
 449                         }
 450                 }
 451                 break;
 452         }
 453
 454 do_more_inside_frame:
 455
 456         /*
 457          * Deal with masking if we are in client -> server direction and
 458          * the wp demands it
 459          */
 460
 461         if (masked7) {
 462                 if (!wsi->u.ws.inside_frame)
 463                         if (lws_0405_frame_mask_generate(wsi)) {
 464                                 lwsl_err("frame mask generation failed\n");
 465                                 return -1;
 466                         }
 467
 468                 /*
 469                  * in v7, just mask the payload
 470                  */
 471                 if (dropmask) { /* never set if already inside frame */
 472                         for (n = 4; n < (int)len + 4; n++)
 473                                 dropmask[n] = dropmask[n] ^ wsi->u.ws.mask[
 474                                         (wsi->u.ws.mask_idx++) & 3];
 475
 476                         /* copy the frame nonce into place */
 477                         memcpy(dropmask, wsi->u.ws.mask, 4);
 478                 }
 479         }
 480
 481 send_raw:
 482         switch ((int)wp) {
 483         case LWS_WRITE_CLOSE:
 484 /*              lwsl_hexdump(&buf[-pre], len); */
 485         case LWS_WRITE_HTTP:
 486         case LWS_WRITE_HTTP_FINAL:
 487         case LWS_WRITE_HTTP_HEADERS:
 488         case LWS_WRITE_PONG:
 489         case LWS_WRITE_PING:
 490 #ifdef LWS_USE_HTTP2
 491                 if (wsi->mode == LWSCM_HTTP2_SERVING) {
 492                         unsigned char flags = 0;
 493
 494                         n = LWS_HTTP2_FRAME_TYPE_DATA;
 495                         if (wp == LWS_WRITE_HTTP_HEADERS) {
 496                                 n = LWS_HTTP2_FRAME_TYPE_HEADERS;
 497                                 flags = LWS_HTTP2_FLAG_END_HEADERS;
 498                                 if (wsi->u.http2.send_END_STREAM)
 499                                         flags |= LWS_HTTP2_FLAG_END_STREAM;
 500                         }
 501
 502                         if ((wp == LWS_WRITE_HTTP ||
 503                              wp == LWS_WRITE_HTTP_FINAL) &&
 504                             wsi->u.http.content_length) {
 505                                 wsi->u.http.content_remain -= len;
 506                                 lwsl_info("%s: content_remain = %lu\n", __func__,
 507                                           (unsigned long)wsi->u.http.content_remain);
 508                                 if (!wsi->u.http.content_remain) {
 509                                         lwsl_info("%s: selecting final write mode\n", __func__);
 510                                         wp = LWS_WRITE_HTTP_FINAL;
 511                                 }
 512                         }
 513
 514                         if (wp == LWS_WRITE_HTTP_FINAL && wsi->u.http2.END_STREAM) {
 515                                 lwsl_info("%s: setting END_STREAM\n", __func__);
 516                                 flags |= LWS_HTTP2_FLAG_END_STREAM;
 517                         }
 518
 519                         return lws_http2_frame_write(wsi, n, flags,
 520                                         wsi->u.http2.my_stream_id, len, buf);
 521                 }
 522 #endif
 523                 return lws_issue_raw(wsi, (unsigned char *)buf - pre, len + pre);
 524         default:
 525                 break;
 526         }
 527
 528         /*
 529          * give any active extensions a chance to munge the buffer
 530          * before send.  We pass in a pointer to an lws_tokens struct
 531          * prepared with the default buffer and content length that's in
 532          * there.  Rather than rewrite the default buffer, extensions
 533          * that expect to grow the buffer can adapt .token to
 534          * point to their own per-connection buffer in the extension
 535          * user allocation.  By default with no extensions or no
 536          * extension callback handling, just the normal input buffer is
 537          * used then so it is efficient.
 538          *
 539          * callback returns 1 in case it wants to spill more buffers
 540          *
 541          * This takes care of holding the buffer if send is incomplete, ie,
 542          * if wsi->u.ws.clean_buffer is 0 (meaning an extension meddled with
 543          * the buffer).  If wsi->u.ws.clean_buffer is 1, it will instead
 544          * return to the user code how much OF THE USER BUFFER was consumed.
 545          */
 546
 547         n = lws_issue_raw_ext_access(wsi, buf - pre, len + pre);
 548         wsi->u.ws.inside_frame = 1;
 549         if (n <= 0)
 550                 return n;
 551
 552         if (n == (int)len + pre) {
 553                 /* everything in the buffer was handled (or rebuffered...) */
 554                 wsi->u.ws.inside_frame = 0;
 555                 return orig_len;
 556         }
 557
 558         /*
 559          * it is how many bytes of user buffer got sent... may be < orig_len
 560          * in which case callback when writable has already been arranged
 561          * and user code can call lws_write() again with the rest
 562          * later.
 563          */
 564
 565         return n - pre;
 566 }
 567
 568 LWS_VISIBLE int lws_serve_http_file_fragment(struct lws *wsi)
 569 {
 570         struct lws_context *context = wsi->context;
 571         struct lws_context_per_thread *pt = &context->pt[(int)wsi->tsi];
 572         struct lws_process_html_args args;
 573         lws_filepos_t amount, poss;
 574         unsigned char *p;
 575 #if defined(LWS_WITH_RANGES)
 576         unsigned char finished = 0;
 577 #endif
 578         int n, m;
 579
 580         // lwsl_notice("%s (trunc len %d)\n", __func__, wsi->trunc_len);
 581
 582         while (wsi->http2_substream || !lws_send_pipe_choked(wsi)) {
 583
 584                 if (wsi->trunc_len) {
 585                         if (lws_issue_raw(wsi, wsi->trunc_alloc +
 586                                           wsi->trunc_offset,
 587                                           wsi->trunc_len) < 0) {
 588                                 lwsl_info("%s: closing\n", __func__);
 589                                 goto file_had_it;
 590                         }
 591                         continue;
 592                 }
 593
 594                 if (wsi->u.http.filepos == wsi->u.http.filelen)
 595                         goto all_sent;
 596
 597                 n = 0;
 598
 599                 p = pt->serv_buf;
 600
 601 #if defined(LWS_WITH_RANGES)
 602                 if (wsi->u.http.range.count_ranges && !wsi->u.http.range.inside) {
 603
 604                         lwsl_notice("%s: doing range start %llu\n", __func__, wsi->u.http.range.start);
 605
 606                         if ((long)lws_vfs_file_seek_cur(wsi->u.http.fop_fd,
 607                                                    wsi->u.http.range.start -
 608                                                    wsi->u.http.filepos) < 0)
 609                                 goto file_had_it;
 610
 611                         wsi->u.http.filepos = wsi->u.http.range.start;
 612
 613                         if (wsi->u.http.range.count_ranges > 1) {
 614                                 n =  lws_snprintf((char *)p, context->pt_serv_buf_size,
 615                                         "_lws\x0d\x0a"
 616                                         "Content-Type: %s\x0d\x0a"
 617                                         "Content-Range: bytes %llu-%llu/%llu\x0d\x0a"
 618                                         "\x0d\x0a",
 619                                         wsi->u.http.multipart_content_type,
 620                                         wsi->u.http.range.start,
 621                                         wsi->u.http.range.end,
 622                                         wsi->u.http.range.extent);
 623                                 p += n;
 624                         }
 625
 626                         wsi->u.http.range.budget = wsi->u.http.range.end -
 627                                                    wsi->u.http.range.start + 1;
 628                         wsi->u.http.range.inside = 1;
 629                 }
 630 #endif
 631
 632                 poss = context->pt_serv_buf_size - n;
 633
 634                 /*
 635                  * if there is a hint about how much we will do well to send at one time,
 636                  * restrict ourselves to only trying to send that.
 637                  */
 638                 if (wsi->protocol->tx_packet_size && poss > wsi->protocol->tx_packet_size)
 639                         poss = wsi->protocol->tx_packet_size;
 640
 641 #if defined(LWS_WITH_RANGES)
 642                 if (wsi->u.http.range.count_ranges) {
 643                         if (wsi->u.http.range.count_ranges > 1)
 644                                 poss -= 7; /* allow for final boundary */
 645                         if (poss > wsi->u.http.range.budget)
 646                                 poss = wsi->u.http.range.budget;
 647                 }
 648 #endif
 649                 if (wsi->sending_chunked) {
 650                         /* we need to drop the chunk size in here */
 651                         p += 10;
 652                         /* allow for the chunk to grow by 128 in translation */
 653                         poss -= 10 + 128;
 654                 }
 655
 656                 if (lws_vfs_file_read(wsi->u.http.fop_fd, &amount, p, poss) < 0)
 657                         goto file_had_it; /* caller will close */
 658
 659                 //lwsl_notice("amount %ld\n", amount);
 660
 661                 if (wsi->sending_chunked)
 662                         n = (int)amount;
 663                 else
 664                         n = (p - pt->serv_buf) + (int)amount;
 665                 if (n) {
 666                         lws_set_timeout(wsi, PENDING_TIMEOUT_HTTP_CONTENT,
 667                                         context->timeout_secs);
 668
 669                         if (wsi->sending_chunked) {
 670                                 args.p = (char *)p;
 671                                 args.len = n;
 672                                 args.max_len = poss + 128;
 673                                 args.final = wsi->u.http.filepos + n ==
 674                                              wsi->u.http.filelen;
 675                                 if (user_callback_handle_rxflow(
 676                                      wsi->vhost->protocols[(int)wsi->protocol_interpret_idx].callback, wsi,
 677                                      LWS_CALLBACK_PROCESS_HTML,
 678                                      wsi->user_space, &args, 0) < 0)
 679                                         goto file_had_it;
 680                                 n = args.len;
 681                                 p = (unsigned char *)args.p;
 682                         } else
 683                                 p = pt->serv_buf;
 684
 685 #if defined(LWS_WITH_RANGES)
 686                         if (wsi->u.http.range.send_ctr + 1 ==
 687                                 wsi->u.http.range.count_ranges && // last range
 688                             wsi->u.http.range.count_ranges > 1 && // was 2+ ranges (ie, multipart)
 689                             wsi->u.http.range.budget - amount == 0) {// final part
 690                                 n += lws_snprintf((char *)pt->serv_buf + n, 6,
 691                                         "_lws\x0d\x0a"); // append trailing boundary
 692                                 lwsl_debug("added trailing boundary\n");
 693                         }
 694 #endif
 695                         m = lws_write(wsi, p, n,
 696                                       wsi->u.http.filepos == wsi->u.http.filelen ?
 697                                         LWS_WRITE_HTTP_FINAL :
 698                                         LWS_WRITE_HTTP
 699                                 );
 700                         if (m < 0)
 701                                 goto file_had_it;
 702
 703                         wsi->u.http.filepos += amount;
 704
 705 #if defined(LWS_WITH_RANGES)
 706                         if (wsi->u.http.range.count_ranges >= 1) {
 707                                 wsi->u.http.range.budget -= amount;
 708                                 if (wsi->u.http.range.budget == 0) {
 709                                         lwsl_notice("range budget exhausted\n");
 710                                         wsi->u.http.range.inside = 0;
 711                                         wsi->u.http.range.send_ctr++;
 712
 713                                         if (lws_ranges_next(&wsi->u.http.range) < 1) {
 714                                                 finished = 1;
 715                                                 goto all_sent;
 716                                         }
 717                                 }
 718                         }
 719 #endif
 720
 721                         if (m != n) {
 722                                 /* adjust for what was not sent */
 723                                 if (lws_vfs_file_seek_cur(wsi->u.http.fop_fd,
 724                                                            m - n) ==
 725                                                              (unsigned long)-1)
 726                                         goto file_had_it;
 727                         }
 728                 }
 729 all_sent:
 730                 if ((!wsi->trunc_len && wsi->u.http.filepos == wsi->u.http.filelen)
 731 #if defined(LWS_WITH_RANGES)
 732                     || finished)
 733 #else
 734                 )
 735 #endif
 736                      {
 737                         wsi->state = LWSS_HTTP;
 738                         /* we might be in keepalive, so close it off here */
 739                         lws_vfs_file_close(&wsi->u.http.fop_fd);
 740
 741                         lwsl_debug("file completed\n");
 742
 743                         if (wsi->protocol->callback)
 744                                 /* ignore callback returned value */
 745                                 if (user_callback_handle_rxflow(
 746                                      wsi->protocol->callback, wsi,
 747                                      LWS_CALLBACK_HTTP_FILE_COMPLETION,
 748                                      wsi->user_space, NULL, 0) < 0)
 749                                         return -1;
 750
 751                         return 1;  /* >0 indicates completed */
 752                 }
 753         }
 754
 755         lws_callback_on_writable(wsi);
 756
 757         return 0; /* indicates further processing must be done */
 758
 759 file_had_it:
 760         lws_vfs_file_close(&wsi->u.http.fop_fd);
 761
 762         return -1;
 763 }
 764
 765 #if LWS_POSIX
 766 LWS_VISIBLE int
 767 lws_ssl_capable_read_no_ssl(struct lws *wsi, unsigned char *buf, int len)
 768 {
 769         int n;
 770
 771         n = recv(wsi->desc.sockfd, (char *)buf, len, 0);
 772         if (n >= 0) {
 773                 if (wsi->vhost)
 774                         wsi->vhost->conn_stats.rx += n;
 775                 lws_restart_ws_ping_pong_timer(wsi);
 776                 return n;
 777         }
 778 #if LWS_POSIX
 779         if (LWS_ERRNO == LWS_EAGAIN ||
 780             LWS_ERRNO == LWS_EWOULDBLOCK ||
 781             LWS_ERRNO == LWS_EINTR)
 782                 return LWS_SSL_CAPABLE_MORE_SERVICE;
 783 #endif
 784         lwsl_notice("error on reading from skt : %d\n", LWS_ERRNO);
 785         return LWS_SSL_CAPABLE_ERROR;
 786 }
 787
 788 LWS_VISIBLE int
 789 lws_ssl_capable_write_no_ssl(struct lws *wsi, unsigned char *buf, int len)
 790 {
 791         int n = 0;
 792
 793 #if LWS_POSIX
 794         n = send(wsi->desc.sockfd, (char *)buf, len, MSG_NOSIGNAL);
 795 //      lwsl_info("%s: sent len %d result %d", __func__, len, n);
 796         if (n >= 0)
 797                 return n;
 798
 799         if (LWS_ERRNO == LWS_EAGAIN ||
 800             LWS_ERRNO == LWS_EWOULDBLOCK ||
 801             LWS_ERRNO == LWS_EINTR) {
 802                 if (LWS_ERRNO == LWS_EWOULDBLOCK) {
 803                         lws_set_blocking_send(wsi);
 804                 }
 805
 806                 return LWS_SSL_CAPABLE_MORE_SERVICE;
 807         }
 808 #else
 809         (void)n;
 810         (void)wsi;
 811         (void)buf;
 812         (void)len;
 813         // !!!
 814 #endif
 815
 816         lwsl_debug("ERROR writing len %d to skt fd %d err %d / errno %d\n", len, wsi->desc.sockfd, n, LWS_ERRNO);
 817         return LWS_SSL_CAPABLE_ERROR;
 818 }
 819 #endif
 820 LWS_VISIBLE int
 821 lws_ssl_pending_no_ssl(struct lws *wsi)
 822 {
 823         (void)wsi;
 824 #if defined(LWS_WITH_ESP32)
 825         return 100;
 826 #else
 827         return 0;
 828 #endif
 829 }