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         struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];
  99         size_t real_len = len;
 100         unsigned int n;
 101         int m;
 102
 103         lws_stats_atomic_bump(wsi->context, pt, LWSSTATS_C_API_WRITE, 1);
 104
 105         if (!len)
 106                 return 0;
 107         /* just ignore sends after we cleared the truncation buffer */
 108         if (wsi->state == LWSS_FLUSHING_STORED_SEND_BEFORE_CLOSE &&
 109             !wsi->trunc_len)
 110                 return len;
 111
 112         if (wsi->trunc_len && (buf < wsi->trunc_alloc ||
 113             buf > (wsi->trunc_alloc + wsi->trunc_len + wsi->trunc_offset))) {
 114                 char dump[20];
 115                 strncpy(dump, (char *)buf, sizeof(dump) - 1);
 116                 dump[sizeof(dump) - 1] = '\0';
 117 #if defined(LWS_WITH_ESP8266)
 118                 lwsl_err("****** %p: Sending new %lu (%s), pending truncated ...\n",
 119                          wsi, (unsigned long)len, dump);
 120 #else
 121                 lwsl_err("****** %p: Sending new %lu (%s), pending truncated ...\n"
 122                          "       It's illegal to do an lws_write outside of\n"
 123                          "       the writable callback: fix your code",
 124                          wsi, (unsigned long)len, dump);
 125 #endif
 126                 assert(0);
 127
 128                 return -1;
 129         }
 130
 131         m = lws_ext_cb_active(wsi, LWS_EXT_CB_PACKET_TX_DO_SEND, &buf, len);
 132         if (m < 0)
 133                 return -1;
 134         if (m) /* handled */ {
 135                 n = m;
 136                 goto handle_truncated_send;
 137         }
 138
 139         if (!lws_socket_is_valid(wsi->desc.sockfd))
 140                 lwsl_warn("** error invalid sock but expected to send\n");
 141
 142         /* limit sending */
 143         if (wsi->protocol->tx_packet_size)
 144                 n = wsi->protocol->tx_packet_size;
 145         else {
 146                 n = wsi->protocol->rx_buffer_size;
 147                 if (!n)
 148                         n = context->pt_serv_buf_size;
 149         }
 150         n += LWS_PRE + 4;
 151         if (n > len)
 152                 n = len;
 153 #if defined(LWS_WITH_ESP8266)
 154         if (wsi->pending_send_completion) {
 155                 n = 0;
 156                 goto handle_truncated_send;
 157         }
 158 #endif
 159
 160         /* nope, send it on the socket directly */
 161         lws_latency_pre(context, wsi);
 162         n = lws_ssl_capable_write(wsi, buf, n);
 163         lws_latency(context, wsi, "send lws_issue_raw", n, n == len);
 164
 165         //lwsl_notice("lws_ssl_capable_write: %d\n", n);
 166
 167         switch (n) {
 168         case LWS_SSL_CAPABLE_ERROR:
 169                 /* we're going to close, let close know sends aren't possible */
 170                 wsi->socket_is_permanently_unusable = 1;
 171                 return -1;
 172         case LWS_SSL_CAPABLE_MORE_SERVICE:
 173                 /* nothing got sent, not fatal, retry the whole thing later */
 174                 n = 0;
 175                 break;
 176         }
 177
 178 handle_truncated_send:
 179         /*
 180          * we were already handling a truncated send?
 181          */
 182         if (wsi->trunc_len) {
 183                 lwsl_info("%p partial adv %d (vs %ld)\n", wsi, n, (long)real_len);
 184                 wsi->trunc_offset += n;
 185                 wsi->trunc_len -= n;
 186
 187                 if (!wsi->trunc_len) {
 188                         lwsl_info("***** %p partial send completed\n", wsi);
 189                         /* done with it, but don't free it */
 190                         n = real_len;
 191                         if (wsi->state == LWSS_FLUSHING_STORED_SEND_BEFORE_CLOSE) {
 192                                 lwsl_info("***** %p signalling to close now\n", wsi);
 193                                 return -1; /* retry closing now */
 194                         }
 195                 }
 196                 /* always callback on writeable */
 197                 lws_callback_on_writable(wsi);
 198
 199                 return n;
 200         }
 201
 202         if ((unsigned int)n == real_len)
 203                 /* what we just sent went out cleanly */
 204                 return n;
 205
 206         /*
 207          * Newly truncated send.  Buffer the remainder (it will get
 208          * first priority next time the socket is writable)
 209          */
 210         lwsl_debug("%p new partial sent %d from %lu total\n", wsi, n,
 211                     (unsigned long)real_len);
 212
 213         lws_stats_atomic_bump(wsi->context, pt, LWSSTATS_C_WRITE_PARTIALS, 1);
 214         lws_stats_atomic_bump(wsi->context, pt, LWSSTATS_B_PARTIALS_ACCEPTED_PARTS, n);
 215
 216         /*
 217          *  - if we still have a suitable malloc lying around, use it
 218          *  - or, if too small, reallocate it
 219          *  - or, if no buffer, create it
 220          */
 221         if (!wsi->trunc_alloc || real_len - n > wsi->trunc_alloc_len) {
 222                 lws_free(wsi->trunc_alloc);
 223
 224                 wsi->trunc_alloc_len = real_len - n;
 225                 wsi->trunc_alloc = lws_malloc(real_len - n);
 226                 if (!wsi->trunc_alloc) {
 227                         lwsl_err("truncated send: unable to malloc %lu\n",
 228                                  (unsigned long)(real_len - n));
 229                         return -1;
 230                 }
 231         }
 232         wsi->trunc_offset = 0;
 233         wsi->trunc_len = real_len - n;
 234         memcpy(wsi->trunc_alloc, buf + n, real_len - n);
 235
 236         /* since something buffered, force it to get another chance to send */
 237         lws_callback_on_writable(wsi);
 238
 239         return real_len;
 240 }
 241
 242 LWS_VISIBLE int lws_write(struct lws *wsi, unsigned char *buf, size_t len,
 243                           enum lws_write_protocol wp)
 244 {
 245         struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];
 246         int masked7 = (wsi->mode == LWSCM_WS_CLIENT);
 247         unsigned char is_masked_bit = 0;
 248         unsigned char *dropmask = NULL;
 249         struct lws_tokens eff_buf;
 250         int pre = 0, n;
 251         size_t orig_len = len;
 252
 253         lws_stats_atomic_bump(wsi->context, pt, LWSSTATS_C_API_LWS_WRITE, 1);
 254
 255         if ((int)len < 0) {
 256                 lwsl_err("%s: suspicious len int %d, ulong %lu\n", __func__,
 257                                 (int)len, (unsigned long)len);
 258                 return -1;
 259         }
 260
 261         lws_stats_atomic_bump(wsi->context, pt, LWSSTATS_B_WRITE, len);
 262
 263 #ifdef LWS_WITH_ACCESS_LOG
 264         wsi->access_log.sent += len;
 265 #endif
 266         if (wsi->vhost)
 267                 wsi->vhost->conn_stats.tx += len;
 268
 269         if (wsi->state == LWSS_ESTABLISHED && wsi->u.ws.tx_draining_ext) {
 270                 /* remove us from the list */
 271                 struct lws **w = &pt->tx_draining_ext_list;
 272                 lwsl_debug("%s: TX EXT DRAINING: Remove from list\n", __func__);
 273                 wsi->u.ws.tx_draining_ext = 0;
 274                 /* remove us from context draining ext list */
 275                 while (*w) {
 276                         if (*w == wsi) {
 277                                 *w = wsi->u.ws.tx_draining_ext_list;
 278                                 break;
 279                         }
 280                         w = &((*w)->u.ws.tx_draining_ext_list);
 281                 }
 282                 wsi->u.ws.tx_draining_ext_list = NULL;
 283                 wp = (wsi->u.ws.tx_draining_stashed_wp & 0xc0) |
 284                                 LWS_WRITE_CONTINUATION;
 285
 286                 lwsl_ext("FORCED draining wp to 0x%02X\n", wp);
 287         }
 288
 289         lws_restart_ws_ping_pong_timer(wsi);
 290
 291         if (wp == LWS_WRITE_HTTP ||
 292             wp == LWS_WRITE_HTTP_FINAL ||
 293             wp == LWS_WRITE_HTTP_HEADERS)
 294                 goto send_raw;
 295
 296         /* if not in a state to send stuff, then just send nothing */
 297
 298         if (wsi->state != LWSS_ESTABLISHED &&
 299             ((wsi->state != LWSS_RETURNED_CLOSE_ALREADY &&
 300               wsi->state != LWSS_AWAITING_CLOSE_ACK) ||
 301                             wp != LWS_WRITE_CLOSE))
 302                 return 0;
 303
 304         /* if we are continuing a frame that already had its header done */
 305
 306         if (wsi->u.ws.inside_frame) {
 307                 lwsl_debug("INSIDE FRAME\n");
 308                 goto do_more_inside_frame;
 309         }
 310
 311         wsi->u.ws.clean_buffer = 1;
 312
 313         /*
 314          * give a chance to the extensions to modify payload
 315          * the extension may decide to produce unlimited payload erratically
 316          * (eg, compression extension), so we require only that if he produces
 317          * something, it will be a complete fragment of the length known at
 318          * the time (just the fragment length known), and if he has
 319          * more we will come back next time he is writeable and allow him to
 320          * produce more fragments until he's drained.
 321          *
 322          * This allows what is sent each time it is writeable to be limited to
 323          * a size that can be sent without partial sends or blocking, allows
 324          * interleaving of control frames and other connection service.
 325          */
 326         eff_buf.token = (char *)buf;
 327         eff_buf.token_len = len;
 328
 329         switch ((int)wp) {
 330         case LWS_WRITE_PING:
 331         case LWS_WRITE_PONG:
 332         case LWS_WRITE_CLOSE:
 333                 break;
 334         default:
 335                 n = lws_ext_cb_active(wsi, LWS_EXT_CB_PAYLOAD_TX, &eff_buf, wp);
 336                 if (n < 0)
 337                         return -1;
 338
 339                 if (n && eff_buf.token_len) {
 340                         /* extension requires further draining */
 341                         wsi->u.ws.tx_draining_ext = 1;
 342                         wsi->u.ws.tx_draining_ext_list = pt->tx_draining_ext_list;
 343                         pt->tx_draining_ext_list = wsi;
 344                         /* we must come back to do more */
 345                         lws_callback_on_writable(wsi);
 346                         /*
 347                          * keep a copy of the write type for the overall
 348                          * action that has provoked generation of these
 349                          * fragments, so the last guy can use its FIN state.
 350                          */
 351                         wsi->u.ws.tx_draining_stashed_wp = wp;
 352                         /* this is definitely not actually the last fragment
 353                          * because the extension asserted he has more coming
 354                          * So make sure this intermediate one doesn't go out
 355                          * with a FIN.
 356                          */
 357                         wp |= LWS_WRITE_NO_FIN;
 358                 }
 359
 360                 if (eff_buf.token_len && wsi->u.ws.stashed_write_pending) {
 361                         wsi->u.ws.stashed_write_pending = 0;
 362                         wp = (wp &0xc0) | (int)wsi->u.ws.stashed_write_type;
 363                 }
 364         }
 365
 366         /*
 367          * an extension did something we need to keep... for example, if
 368          * compression extension, it has already updated its state according
 369          * to this being issued
 370          */
 371         if ((char *)buf != eff_buf.token) {
 372                 /*
 373                  * ext might eat it, but no have anything to issue yet
 374                  * in that case we have to follow his lead, but stash and
 375                  * replace the write type that was lost here the first time.
 376                  */
 377                 if (len && !eff_buf.token_len) {
 378                         if (!wsi->u.ws.stashed_write_pending)
 379                                 wsi->u.ws.stashed_write_type = (char)wp & 0x3f;
 380                         wsi->u.ws.stashed_write_pending = 1;
 381                         return len;
 382                 }
 383                 /*
 384                  * extension recreated it:
 385                  * need to buffer this if not all sent
 386                  */
 387                 wsi->u.ws.clean_buffer = 0;
 388         }
 389
 390         buf = (unsigned char *)eff_buf.token;
 391         len = eff_buf.token_len;
 392
 393         switch (wsi->ietf_spec_revision) {
 394         case 13:
 395                 if (masked7) {
 396                         pre += 4;
 397                         dropmask = &buf[0 - pre];
 398                         is_masked_bit = 0x80;
 399                 }
 400
 401                 switch (wp & 0xf) {
 402                 case LWS_WRITE_TEXT:
 403                         n = LWSWSOPC_TEXT_FRAME;
 404                         break;
 405                 case LWS_WRITE_BINARY:
 406                         n = LWSWSOPC_BINARY_FRAME;
 407                         break;
 408                 case LWS_WRITE_CONTINUATION:
 409                         n = LWSWSOPC_CONTINUATION;
 410                         break;
 411
 412                 case LWS_WRITE_CLOSE:
 413                         n = LWSWSOPC_CLOSE;
 414                         break;
 415                 case LWS_WRITE_PING:
 416                         n = LWSWSOPC_PING;
 417                         break;
 418                 case LWS_WRITE_PONG:
 419                         n = LWSWSOPC_PONG;
 420                         break;
 421                 default:
 422                         lwsl_warn("lws_write: unknown write opc / wp\n");
 423                         return -1;
 424                 }
 425
 426                 if (!(wp & LWS_WRITE_NO_FIN))
 427                         n |= 1 << 7;
 428
 429                 if (len < 126) {
 430                         pre += 2;
 431                         buf[-pre] = n;
 432                         buf[-pre + 1] = (unsigned char)(len | is_masked_bit);
 433                 } else {
 434                         if (len < 65536) {
 435                                 pre += 4;
 436                                 buf[-pre] = n;
 437                                 buf[-pre + 1] = 126 | is_masked_bit;
 438                                 buf[-pre + 2] = (unsigned char)(len >> 8);
 439                                 buf[-pre + 3] = (unsigned char)len;
 440                         } else {
 441                                 pre += 10;
 442                                 buf[-pre] = n;
 443                                 buf[-pre + 1] = 127 | is_masked_bit;
 444 #if defined __LP64__
 445                                         buf[-pre + 2] = (len >> 56) & 0x7f;
 446                                         buf[-pre + 3] = len >> 48;
 447                                         buf[-pre + 4] = len >> 40;
 448                                         buf[-pre + 5] = len >> 32;
 449 #else
 450                                         buf[-pre + 2] = 0;
 451                                         buf[-pre + 3] = 0;
 452                                         buf[-pre + 4] = 0;
 453                                         buf[-pre + 5] = 0;
 454 #endif
 455                                 buf[-pre + 6] = (unsigned char)(len >> 24);
 456                                 buf[-pre + 7] = (unsigned char)(len >> 16);
 457                                 buf[-pre + 8] = (unsigned char)(len >> 8);
 458                                 buf[-pre + 9] = (unsigned char)len;
 459                         }
 460                 }
 461                 break;
 462         }
 463
 464 do_more_inside_frame:
 465
 466         /*
 467          * Deal with masking if we are in client -> server direction and
 468          * the wp demands it
 469          */
 470
 471         if (masked7) {
 472                 if (!wsi->u.ws.inside_frame)
 473                         if (lws_0405_frame_mask_generate(wsi)) {
 474                                 lwsl_err("frame mask generation failed\n");
 475                                 return -1;
 476                         }
 477
 478                 /*
 479                  * in v7, just mask the payload
 480                  */
 481                 if (dropmask) { /* never set if already inside frame */
 482                         for (n = 4; n < (int)len + 4; n++)
 483                                 dropmask[n] = dropmask[n] ^ wsi->u.ws.mask[
 484                                         (wsi->u.ws.mask_idx++) & 3];
 485
 486                         /* copy the frame nonce into place */
 487                         memcpy(dropmask, wsi->u.ws.mask, 4);
 488                 }
 489         }
 490
 491 send_raw:
 492         switch ((int)wp) {
 493         case LWS_WRITE_CLOSE:
 494 /*              lwsl_hexdump(&buf[-pre], len); */
 495         case LWS_WRITE_HTTP:
 496         case LWS_WRITE_HTTP_FINAL:
 497         case LWS_WRITE_HTTP_HEADERS:
 498         case LWS_WRITE_PONG:
 499         case LWS_WRITE_PING:
 500 #ifdef LWS_USE_HTTP2
 501                 if (wsi->mode == LWSCM_HTTP2_SERVING) {
 502                         unsigned char flags = 0;
 503
 504                         n = LWS_HTTP2_FRAME_TYPE_DATA;
 505                         if (wp == LWS_WRITE_HTTP_HEADERS) {
 506                                 n = LWS_HTTP2_FRAME_TYPE_HEADERS;
 507                                 flags = LWS_HTTP2_FLAG_END_HEADERS;
 508                                 if (wsi->u.http2.send_END_STREAM)
 509                                         flags |= LWS_HTTP2_FLAG_END_STREAM;
 510                         }
 511
 512                         if ((wp == LWS_WRITE_HTTP ||
 513                              wp == LWS_WRITE_HTTP_FINAL) &&
 514                             wsi->u.http.content_length) {
 515                                 wsi->u.http.content_remain -= len;
 516                                 lwsl_info("%s: content_remain = %lu\n", __func__,
 517                                           (unsigned long)wsi->u.http.content_remain);
 518                                 if (!wsi->u.http.content_remain) {
 519                                         lwsl_info("%s: selecting final write mode\n", __func__);
 520                                         wp = LWS_WRITE_HTTP_FINAL;
 521                                 }
 522                         }
 523
 524                         if (wp == LWS_WRITE_HTTP_FINAL && wsi->u.http2.END_STREAM) {
 525                                 lwsl_info("%s: setting END_STREAM\n", __func__);
 526                                 flags |= LWS_HTTP2_FLAG_END_STREAM;
 527                         }
 528
 529                         return lws_http2_frame_write(wsi, n, flags,
 530                                         wsi->u.http2.my_stream_id, len, buf);
 531                 }
 532 #endif
 533                 return lws_issue_raw(wsi, (unsigned char *)buf - pre, len + pre);
 534         default:
 535                 break;
 536         }
 537
 538         /*
 539          * give any active extensions a chance to munge the buffer
 540          * before send.  We pass in a pointer to an lws_tokens struct
 541          * prepared with the default buffer and content length that's in
 542          * there.  Rather than rewrite the default buffer, extensions
 543          * that expect to grow the buffer can adapt .token to
 544          * point to their own per-connection buffer in the extension
 545          * user allocation.  By default with no extensions or no
 546          * extension callback handling, just the normal input buffer is
 547          * used then so it is efficient.
 548          *
 549          * callback returns 1 in case it wants to spill more buffers
 550          *
 551          * This takes care of holding the buffer if send is incomplete, ie,
 552          * if wsi->u.ws.clean_buffer is 0 (meaning an extension meddled with
 553          * the buffer).  If wsi->u.ws.clean_buffer is 1, it will instead
 554          * return to the user code how much OF THE USER BUFFER was consumed.
 555          */
 556
 557         n = lws_issue_raw_ext_access(wsi, buf - pre, len + pre);
 558         wsi->u.ws.inside_frame = 1;
 559         if (n <= 0)
 560                 return n;
 561
 562         if (n == (int)len + pre) {
 563                 /* everything in the buffer was handled (or rebuffered...) */
 564                 wsi->u.ws.inside_frame = 0;
 565                 return orig_len;
 566         }
 567
 568         /*
 569          * it is how many bytes of user buffer got sent... may be < orig_len
 570          * in which case callback when writable has already been arranged
 571          * and user code can call lws_write() again with the rest
 572          * later.
 573          */
 574
 575         return n - pre;
 576 }
 577
 578 LWS_VISIBLE int lws_serve_http_file_fragment(struct lws *wsi)
 579 {
 580         struct lws_context *context = wsi->context;
 581         struct lws_context_per_thread *pt = &context->pt[(int)wsi->tsi];
 582         struct lws_process_html_args args;
 583         lws_filepos_t amount, poss;
 584         unsigned char *p;
 585 #if defined(LWS_WITH_RANGES)
 586         unsigned char finished = 0;
 587 #endif
 588         int n, m;
 589
 590         // lwsl_notice("%s (trunc len %d)\n", __func__, wsi->trunc_len);
 591
 592         while (wsi->http2_substream || !lws_send_pipe_choked(wsi)) {
 593
 594                 if (wsi->trunc_len) {
 595                         if (lws_issue_raw(wsi, wsi->trunc_alloc +
 596                                           wsi->trunc_offset,
 597                                           wsi->trunc_len) < 0) {
 598                                 lwsl_info("%s: closing\n", __func__);
 599                                 goto file_had_it;
 600                         }
 601                         continue;
 602                 }
 603
 604                 if (wsi->u.http.filepos == wsi->u.http.filelen)
 605                         goto all_sent;
 606
 607                 n = 0;
 608
 609                 p = pt->serv_buf;
 610
 611 #if defined(LWS_WITH_RANGES)
 612                 if (wsi->u.http.range.count_ranges && !wsi->u.http.range.inside) {
 613
 614                         lwsl_notice("%s: doing range start %llu\n", __func__, wsi->u.http.range.start);
 615
 616                         if ((long)lws_vfs_file_seek_cur(wsi->u.http.fop_fd,
 617                                                    wsi->u.http.range.start -
 618                                                    wsi->u.http.filepos) < 0)
 619                                 goto file_had_it;
 620
 621                         wsi->u.http.filepos = wsi->u.http.range.start;
 622
 623                         if (wsi->u.http.range.count_ranges > 1) {
 624                                 n =  lws_snprintf((char *)p, context->pt_serv_buf_size,
 625                                         "_lws\x0d\x0a"
 626                                         "Content-Type: %s\x0d\x0a"
 627                                         "Content-Range: bytes %llu-%llu/%llu\x0d\x0a"
 628                                         "\x0d\x0a",
 629                                         wsi->u.http.multipart_content_type,
 630                                         wsi->u.http.range.start,
 631                                         wsi->u.http.range.end,
 632                                         wsi->u.http.range.extent);
 633                                 p += n;
 634                         }
 635
 636                         wsi->u.http.range.budget = wsi->u.http.range.end -
 637                                                    wsi->u.http.range.start + 1;
 638                         wsi->u.http.range.inside = 1;
 639                 }
 640 #endif
 641
 642                 poss = context->pt_serv_buf_size - n;
 643
 644                 /*
 645                  * if there is a hint about how much we will do well to send at one time,
 646                  * restrict ourselves to only trying to send that.
 647                  */
 648                 if (wsi->protocol->tx_packet_size && poss > wsi->protocol->tx_packet_size)
 649                         poss = wsi->protocol->tx_packet_size;
 650
 651 #if defined(LWS_WITH_RANGES)
 652                 if (wsi->u.http.range.count_ranges) {
 653                         if (wsi->u.http.range.count_ranges > 1)
 654                                 poss -= 7; /* allow for final boundary */
 655                         if (poss > wsi->u.http.range.budget)
 656                                 poss = wsi->u.http.range.budget;
 657                 }
 658 #endif
 659                 if (wsi->sending_chunked) {
 660                         /* we need to drop the chunk size in here */
 661                         p += 10;
 662                         /* allow for the chunk to grow by 128 in translation */
 663                         poss -= 10 + 128;
 664                 }
 665
 666                 if (lws_vfs_file_read(wsi->u.http.fop_fd, &amount, p, poss) < 0)
 667                         goto file_had_it; /* caller will close */
 668
 669                 //lwsl_notice("amount %ld\n", amount);
 670
 671                 if (wsi->sending_chunked)
 672                         n = (int)amount;
 673                 else
 674                         n = (p - pt->serv_buf) + (int)amount;
 675                 if (n) {
 676                         lws_set_timeout(wsi, PENDING_TIMEOUT_HTTP_CONTENT,
 677                                         context->timeout_secs);
 678
 679                         if (wsi->sending_chunked) {
 680                                 args.p = (char *)p;
 681                                 args.len = n;
 682                                 args.max_len = poss + 128;
 683                                 args.final = wsi->u.http.filepos + n ==
 684                                              wsi->u.http.filelen;
 685                                 if (user_callback_handle_rxflow(
 686                                      wsi->vhost->protocols[(int)wsi->protocol_interpret_idx].callback, wsi,
 687                                      LWS_CALLBACK_PROCESS_HTML,
 688                                      wsi->user_space, &args, 0) < 0)
 689                                         goto file_had_it;
 690                                 n = args.len;
 691                                 p = (unsigned char *)args.p;
 692                         } else
 693                                 p = pt->serv_buf;
 694
 695 #if defined(LWS_WITH_RANGES)
 696                         if (wsi->u.http.range.send_ctr + 1 ==
 697                                 wsi->u.http.range.count_ranges && // last range
 698                             wsi->u.http.range.count_ranges > 1 && // was 2+ ranges (ie, multipart)
 699                             wsi->u.http.range.budget - amount == 0) {// final part
 700                                 n += lws_snprintf((char *)pt->serv_buf + n, 6,
 701                                         "_lws\x0d\x0a"); // append trailing boundary
 702                                 lwsl_debug("added trailing boundary\n");
 703                         }
 704 #endif
 705                         m = lws_write(wsi, p, n,
 706                                       wsi->u.http.filepos == wsi->u.http.filelen ?
 707                                         LWS_WRITE_HTTP_FINAL :
 708                                         LWS_WRITE_HTTP
 709                                 );
 710                         if (m < 0)
 711                                 goto file_had_it;
 712
 713                         wsi->u.http.filepos += amount;
 714
 715 #if defined(LWS_WITH_RANGES)
 716                         if (wsi->u.http.range.count_ranges >= 1) {
 717                                 wsi->u.http.range.budget -= amount;
 718                                 if (wsi->u.http.range.budget == 0) {
 719                                         lwsl_notice("range budget exhausted\n");
 720                                         wsi->u.http.range.inside = 0;
 721                                         wsi->u.http.range.send_ctr++;
 722
 723                                         if (lws_ranges_next(&wsi->u.http.range) < 1) {
 724                                                 finished = 1;
 725                                                 goto all_sent;
 726                                         }
 727                                 }
 728                         }
 729 #endif
 730
 731                         if (m != n) {
 732                                 /* adjust for what was not sent */
 733                                 if (lws_vfs_file_seek_cur(wsi->u.http.fop_fd,
 734                                                            m - n) ==
 735                                                              (unsigned long)-1)
 736                                         goto file_had_it;
 737                         }
 738                 }
 739 all_sent:
 740                 if ((!wsi->trunc_len && wsi->u.http.filepos == wsi->u.http.filelen)
 741 #if defined(LWS_WITH_RANGES)
 742                     || finished)
 743 #else
 744                 )
 745 #endif
 746                      {
 747                         wsi->state = LWSS_HTTP;
 748                         /* we might be in keepalive, so close it off here */
 749                         lws_vfs_file_close(&wsi->u.http.fop_fd);
 750
 751                         lwsl_debug("file completed\n");
 752
 753                         if (wsi->protocol->callback)
 754                                 /* ignore callback returned value */
 755                                 if (user_callback_handle_rxflow(
 756                                      wsi->protocol->callback, wsi,
 757                                      LWS_CALLBACK_HTTP_FILE_COMPLETION,
 758                                      wsi->user_space, NULL, 0) < 0)
 759                                         return -1;
 760
 761                         return 1;  /* >0 indicates completed */
 762                 }
 763         }
 764
 765         lws_callback_on_writable(wsi);
 766
 767         return 0; /* indicates further processing must be done */
 768
 769 file_had_it:
 770         lws_vfs_file_close(&wsi->u.http.fop_fd);
 771
 772         return -1;
 773 }
 774
 775 #if LWS_POSIX
 776 LWS_VISIBLE int
 777 lws_ssl_capable_read_no_ssl(struct lws *wsi, unsigned char *buf, int len)
 778 {
 779         struct lws_context *context = wsi->context;
 780         struct lws_context_per_thread *pt = &context->pt[(int)wsi->tsi];
 781         int n;
 782
 783         lws_stats_atomic_bump(context, pt, LWSSTATS_C_API_READ, 1);
 784
 785         n = recv(wsi->desc.sockfd, (char *)buf, len, 0);
 786         if (n >= 0) {
 787                 if (wsi->vhost)
 788                         wsi->vhost->conn_stats.rx += n;
 789                 lws_stats_atomic_bump(context, pt, LWSSTATS_B_READ, n);
 790                 lws_restart_ws_ping_pong_timer(wsi);
 791                 return n;
 792         }
 793 #if LWS_POSIX
 794         if (LWS_ERRNO == LWS_EAGAIN ||
 795             LWS_ERRNO == LWS_EWOULDBLOCK ||
 796             LWS_ERRNO == LWS_EINTR)
 797                 return LWS_SSL_CAPABLE_MORE_SERVICE;
 798 #endif
 799         lwsl_notice("error on reading from skt : %d\n", LWS_ERRNO);
 800         return LWS_SSL_CAPABLE_ERROR;
 801 }
 802
 803 LWS_VISIBLE int
 804 lws_ssl_capable_write_no_ssl(struct lws *wsi, unsigned char *buf, int len)
 805 {
 806         int n = 0;
 807
 808 #if LWS_POSIX
 809         n = send(wsi->desc.sockfd, (char *)buf, len, MSG_NOSIGNAL);
 810 //      lwsl_info("%s: sent len %d result %d", __func__, len, n);
 811         if (n >= 0)
 812                 return n;
 813
 814         if (LWS_ERRNO == LWS_EAGAIN ||
 815             LWS_ERRNO == LWS_EWOULDBLOCK ||
 816             LWS_ERRNO == LWS_EINTR) {
 817                 if (LWS_ERRNO == LWS_EWOULDBLOCK) {
 818                         lws_set_blocking_send(wsi);
 819                 }
 820
 821                 return LWS_SSL_CAPABLE_MORE_SERVICE;
 822         }
 823 #else
 824         (void)n;
 825         (void)wsi;
 826         (void)buf;
 827         (void)len;
 828         // !!!
 829 #endif
 830
 831         lwsl_debug("ERROR writing len %d to skt fd %d err %d / errno %d\n", len, wsi->desc.sockfd, n, LWS_ERRNO);
 832         return LWS_SSL_CAPABLE_ERROR;
 833 }
 834 #endif
 835 LWS_VISIBLE int
 836 lws_ssl_pending_no_ssl(struct lws *wsi)
 837 {
 838         (void)wsi;
 839 #if defined(LWS_WITH_ESP32)
 840         return 100;
 841 #else
 842         return 0;
 843 #endif
 844 }