git.sesse.net Git - cubemap/blob - httpinput.cpp

   1 #include <assert.h>
   2 #include <errno.h>
   3 #include <netdb.h>
   4 #include <netinet/in.h>
   5 #include <poll.h>
   6 #include <stdint.h>
   7 #include <stdlib.h>
   8 #include <string.h>
   9 #include <sys/ioctl.h>
  10 #include <sys/socket.h>
  11 #include <sys/time.h>
  12 #include <time.h>
  13 #include <unistd.h>
  14 #include <math.h>
  15 #include <map>
  16 #include <string>
  17 #include <utility>
  18 #include <vector>
  19
  20 #include "httpinput.h"
  21 #include "log.h"
  22 #include "metacube2.h"
  23 #include "parse.h"
  24 #include "serverpool.h"
  25 #include "state.pb.h"
  26 #include "stream.h"
  27 #include "timespec.h"
  28 #include "util.h"
  29 #include "version.h"
  30
  31 using namespace std;
  32
  33 namespace {
  34
  35 string host_header(const string &host, const string &port)
  36 {
  37         if (port == "http" || atoi(port.c_str()) == 80) {
  38                 return host;
  39         } else {
  40                 return host + ":" + port;
  41         }
  42 }
  43
  44 }  // namespace
  45
  46 extern ServerPool *servers;
  47
  48 HTTPInput::HTTPInput(const string &url, Input::Encoding encoding)
  49         : state(NOT_CONNECTED),
  50           url(url),
  51           encoding(encoding)
  52 {
  53         stats.url = url;
  54         stats.bytes_received = 0;
  55         stats.data_bytes_received = 0;
  56         stats.metadata_bytes_received = 0;
  57         stats.connect_time = -1;
  58         stats.latency_sec = HUGE_VAL;
  59 }
  60
  61 HTTPInput::HTTPInput(const InputProto &serialized)
  62         : state(State(serialized.state())),
  63           url(serialized.url()),
  64           encoding(serialized.is_metacube_encoded() ?
  65                    Input::INPUT_ENCODING_METACUBE :
  66                    Input::INPUT_ENCODING_RAW),
  67           request(serialized.request()),
  68           request_bytes_sent(serialized.request_bytes_sent()),
  69           response(serialized.response()),
  70           http_header(serialized.http_header()),
  71           stream_header(serialized.stream_header()),
  72           has_metacube_header(serialized.has_metacube_header()),
  73           sock(serialized.sock())
  74 {
  75         pending_data.resize(serialized.pending_data().size());
  76         memcpy(&pending_data[0], serialized.pending_data().data(), serialized.pending_data().size());
  77
  78         string protocol, user;
  79         parse_url(url, &protocol, &user, &host, &port, &path);  // Don't care if it fails.
  80
  81         stats.url = url;
  82         stats.bytes_received = serialized.bytes_received();
  83         stats.data_bytes_received = serialized.data_bytes_received();
  84         stats.metadata_bytes_received = serialized.metadata_bytes_received();
  85         if (serialized.has_connect_time()) {
  86                 stats.connect_time = serialized.connect_time();
  87         } else {
  88                 stats.connect_time = time(nullptr);
  89         }
  90         if (serialized.has_latency_sec()) {
  91                 stats.latency_sec = serialized.latency_sec();
  92         } else {
  93                 stats.latency_sec = HUGE_VAL;
  94         }
  95
  96         last_verbose_connection.tv_sec = -3600;
  97         last_verbose_connection.tv_nsec = 0;
  98 }
  99
 100 void HTTPInput::close_socket()
 101 {
 102         if (sock != -1) {
 103                 safe_close(sock);
 104                 sock = -1;
 105         }
 106
 107         lock_guard<mutex> lock(stats_mutex);
 108         stats.connect_time = -1;
 109 }
 110
 111 InputProto HTTPInput::serialize() const
 112 {
 113         InputProto serialized;
 114         serialized.set_state(state);
 115         serialized.set_url(url);
 116         serialized.set_request(request);
 117         serialized.set_request_bytes_sent(request_bytes_sent);
 118         serialized.set_response(response);
 119         serialized.set_http_header(http_header);
 120         serialized.set_stream_header(stream_header);
 121         serialized.set_pending_data(string(pending_data.begin(), pending_data.end()));
 122         serialized.set_has_metacube_header(has_metacube_header);
 123         serialized.set_sock(sock);
 124         serialized.set_bytes_received(stats.bytes_received);
 125         serialized.set_data_bytes_received(stats.data_bytes_received);
 126         if (isfinite(stats.latency_sec)) {
 127                 serialized.set_latency_sec(stats.latency_sec);
 128         }
 129         serialized.set_connect_time(stats.connect_time);
 130         if (encoding == Input::INPUT_ENCODING_METACUBE) {
 131                 serialized.set_is_metacube_encoded(true);
 132         } else {
 133                 assert(encoding == Input::INPUT_ENCODING_RAW);
 134                 serialized.set_is_metacube_encoded(false);
 135         }
 136         return serialized;
 137 }
 138
 139 int HTTPInput::lookup_and_connect(const string &host, const string &port)
 140 {
 141         addrinfo *ai;
 142         int err = getaddrinfo(host.c_str(), port.c_str(), nullptr, &ai);
 143         if (err != 0) {
 144                 if (!suppress_logging) {
 145                         log(WARNING, "[%s] Lookup of '%s' failed (%s).",
 146                                 url.c_str(), host.c_str(), gai_strerror(err));
 147                 }
 148                 return -1;
 149         }
 150
 151         addrinfo *base_ai = ai;
 152
 153         // Connect to everything in turn until we have a socket.
 154         for ( ; ai && !should_stop(); ai = ai->ai_next) {
 155                 int sock = socket(ai->ai_family, SOCK_STREAM, IPPROTO_TCP);
 156                 if (sock == -1) {
 157                         // Could be e.g. EPROTONOSUPPORT. The show must go on.
 158                         continue;
 159                 }
 160
 161                 // Now do a non-blocking connect. This is important because we want to be able to be
 162                 // woken up, even though it's rather cumbersome.
 163
 164                 // Set the socket as nonblocking.
 165                 int one = 1;
 166                 if (ioctl(sock, FIONBIO, &one) == -1) {
 167                         log_perror("ioctl(FIONBIO)");
 168                         safe_close(sock);
 169                         return -1;
 170                 }
 171
 172                 // Do a non-blocking connect.
 173                 do {
 174                         err = connect(sock, ai->ai_addr, ai->ai_addrlen);
 175                 } while (err == -1 && errno == EINTR);
 176
 177                 if (err == -1 && errno != EINPROGRESS) {
 178                         log_perror("connect");
 179                         safe_close(sock);
 180                         continue;
 181                 }
 182
 183                 // Wait for the connect to complete, or an error to happen.
 184                 for ( ;; ) {
 185                         bool complete = wait_for_activity(sock, POLLIN | POLLOUT, nullptr);
 186                         if (should_stop()) {
 187                                 safe_close(sock);
 188                                 return -1;
 189                         }
 190                         if (complete) {
 191                                 break;
 192                         }
 193                 }
 194
 195                 // Check whether it ended in an error or not.
 196                 socklen_t err_size = sizeof(err);
 197                 if (getsockopt(sock, SOL_SOCKET, SO_ERROR, &err, &err_size) == -1) {
 198                         log_perror("getsockopt");
 199                         safe_close(sock);
 200                         continue;
 201                 }
 202
 203                 errno = err;
 204
 205                 if (err == 0) {
 206                         // Successful connect.
 207                         freeaddrinfo(base_ai);
 208                         return sock;
 209                 }
 210
 211                 safe_close(sock);
 212         }
 213
 214         // Give the last one as error.
 215         if (!suppress_logging) {
 216                 log(WARNING, "[%s] Connect to '%s' failed (%s)",
 217                         url.c_str(), host.c_str(), strerror(errno));
 218         }
 219         freeaddrinfo(base_ai);
 220         return -1;
 221 }
 222
 223 bool HTTPInput::parse_response(const string &request)
 224 {
 225         vector<string> lines = split_lines(response);
 226         if (lines.empty()) {
 227                 if (!suppress_logging) {
 228                         log(WARNING, "[%s] Empty HTTP response from input.", url.c_str());
 229                 }
 230                 return false;
 231         }
 232
 233         vector<string> first_line_tokens = split_tokens(lines[0]);
 234         if (first_line_tokens.size() < 2) {
 235                 if (!suppress_logging) {
 236                         log(WARNING, "[%s] Malformed response line '%s' from input.",
 237                                 url.c_str(), lines[0].c_str());
 238                 }
 239                 return false;
 240         }
 241
 242         int response = atoi(first_line_tokens[1].c_str());
 243         if (response != 200) {
 244                 if (!suppress_logging) {
 245                         log(WARNING, "[%s] Non-200 response '%s' from input.",
 246                                 url.c_str(), lines[0].c_str());
 247                 }
 248                 return false;
 249         }
 250
 251         multimap<string, string> parameters = extract_headers(lines, url);
 252
 253         // Remove “Content-encoding: metacube”.
 254         // TODO: Make case-insensitive.
 255         const auto encoding_it = parameters.find("Content-encoding");
 256         if (encoding_it != parameters.end() && encoding_it->second == "metacube") {
 257                 parameters.erase(encoding_it);
 258         }
 259
 260         // Change “Server: foo” to “Server: metacube/0.1 (reflecting: foo)”
 261         // TODO: Make case-insensitive.
 262         // XXX: Use a Via: instead?
 263         if (parameters.count("Server") == 0) {
 264                 parameters.insert(make_pair("Server", SERVER_IDENTIFICATION));
 265         } else {
 266                 for (auto &key_and_value : parameters) {
 267                         if (key_and_value.first != "Server") {
 268                                 continue;
 269                         }
 270                         key_and_value.second = SERVER_IDENTIFICATION " (reflecting: " + key_and_value.second + ")";
 271                 }
 272         }
 273
 274         // Set “Connection: close”.
 275         // TODO: Make case-insensitive.
 276         parameters.erase("Connection");
 277         parameters.insert(make_pair("Connection", "close"));
 278
 279         // Construct the new HTTP header.
 280         http_header = "HTTP/1.0 200 OK\r\n";
 281         for (const auto &key_and_value : parameters) {
 282                 http_header.append(key_and_value.first + ": " + key_and_value.second + "\r\n");
 283         }
 284
 285         for (int stream_index : stream_indices) {
 286                 servers->set_header(stream_index, http_header, stream_header);
 287         }
 288
 289         return true;
 290 }
 291
 292 void HTTPInput::do_work()
 293 {
 294         timespec last_activity;
 295
 296         // TODO: Make the timeout persist across restarts.
 297         if (state == SENDING_REQUEST || state == RECEIVING_HEADER || state == RECEIVING_DATA) {
 298                 int err = clock_gettime(CLOCK_MONOTONIC_COARSE, &last_activity);
 299                 assert(err != -1);
 300         }
 301
 302         while (!should_stop()) {
 303                 if (state == SENDING_REQUEST || state == RECEIVING_HEADER || state == RECEIVING_DATA) {
 304                         // Give the socket 30 seconds since last activity before we time out.
 305                         static const int timeout_secs = 30;
 306
 307                         timespec now;
 308                         int err = clock_gettime(CLOCK_MONOTONIC_COARSE, &now);
 309                         assert(err != -1);
 310
 311                         timespec elapsed = clock_diff(last_activity, now);
 312                         if (elapsed.tv_sec >= timeout_secs) {
 313                                 // Timeout!
 314                                 if (!suppress_logging) {
 315                                         log(ERROR, "[%s] Timeout after %d seconds, closing.", url.c_str(), elapsed.tv_sec);
 316                                 }
 317                                 state = CLOSING_SOCKET;
 318                                 continue;
 319                         }
 320
 321                         // Basically calculate (30 - (now - last_activity)) = (30 + (last_activity - now)).
 322                         // Add a second of slack to account for differences between clocks.
 323                         timespec timeout = clock_diff(now, last_activity);
 324                         timeout.tv_sec += timeout_secs + 1;
 325                         assert(timeout.tv_sec > 0 || (timeout.tv_sec >= 0 && timeout.tv_nsec > 0));
 326
 327                         bool activity = wait_for_activity(sock, (state == SENDING_REQUEST) ? POLLOUT : POLLIN, &timeout);
 328                         if (activity) {
 329                                 err = clock_gettime(CLOCK_MONOTONIC_COARSE, &last_activity);
 330                                 assert(err != -1);
 331                         } else {
 332                                 // OK. Most likely, should_stop was set, or we have timed out.
 333                                 continue;
 334                         }
 335                 }
 336
 337                 switch (state) {
 338                 case NOT_CONNECTED:
 339                         request.clear();
 340                         request_bytes_sent = 0;
 341                         response.clear();
 342                         pending_data.clear();
 343                         has_metacube_header = false;
 344                         for (int stream_index : stream_indices) {
 345                                 servers->set_header(stream_index, "", "");
 346                         }
 347
 348                         {
 349                                 string protocol, user;  // Thrown away.
 350                                 if (!parse_url(url, &protocol, &user, &host, &port, &path)) {
 351                                         if (!suppress_logging) {
 352                                                 log(WARNING, "[%s] Failed to parse URL '%s'", url.c_str(), url.c_str());
 353                                         }
 354                                         break;
 355                                 }
 356
 357                                 // Remove the brackets around IPv6 address literals.
 358                                 // TODO: See if we can join this with the code in parse_ip_address(),
 359                                 // or maybe even more it into parse_url().
 360                                 if (!host.empty() && host[0] == '[' && host[host.size() - 1] == ']') {
 361                                         host = host.substr(1, host.size() - 2);
 362                                 }
 363                         }
 364
 365                         if (suppress_logging) {
 366                                 // See if there's more than one minute since last time we made a connection
 367                                 // with logging enabled. If so, turn it on again.
 368                                 timespec now;
 369                                 int err = clock_gettime(CLOCK_MONOTONIC_COARSE, &now);
 370                                 assert(err != -1);
 371
 372                                 double elapsed = now.tv_sec - last_verbose_connection.tv_sec +
 373                                         1e-9 * (now.tv_nsec - last_verbose_connection.tv_nsec);
 374                                 if (elapsed > 60.0) {
 375                                         suppress_logging = false;
 376                                 }
 377                         }
 378                         if (!suppress_logging) {
 379                                 int err = clock_gettime(CLOCK_MONOTONIC_COARSE, &last_verbose_connection);
 380                                 assert(err != -1);
 381                         }
 382                         ++num_connection_attempts;
 383                         sock = lookup_and_connect(host, port);
 384                         if (sock != -1) {
 385                                 // Yay, successful connect. Try to set it as nonblocking.
 386                                 int one = 1;
 387                                 if (ioctl(sock, FIONBIO, &one) == -1) {
 388                                         log_perror("ioctl(FIONBIO)");
 389                                         state = CLOSING_SOCKET;
 390                                 } else {
 391                                         state = SENDING_REQUEST;
 392                                         request = "GET " + path + " HTTP/1.0\r\nHost: " + host_header(host, port) + "\r\nUser-Agent: cubemap\r\n\r\n";
 393                                         request_bytes_sent = 0;
 394                                 }
 395
 396                                 lock_guard<mutex> lock(stats_mutex);
 397                                 stats.connect_time = time(nullptr);
 398                                 clock_gettime(CLOCK_MONOTONIC_COARSE, &last_activity);
 399                         }
 400                         break;
 401                 case SENDING_REQUEST: {
 402                         size_t to_send = request.size() - request_bytes_sent;
 403                         int ret;
 404
 405                         do {
 406                                 ret = write(sock, request.data() + request_bytes_sent, to_send);
 407                         } while (ret == -1 && errno == EINTR);
 408
 409                         if (ret == -1) {
 410                                 log_perror("write");
 411                                 state = CLOSING_SOCKET;
 412                                 continue;
 413                         }
 414
 415                         assert(ret >= 0);
 416                         request_bytes_sent += ret;
 417
 418                         if (request_bytes_sent == request.size()) {
 419                                 state = RECEIVING_HEADER;
 420                         }
 421                         break;
 422                 }
 423                 case RECEIVING_HEADER: {
 424                         char buf[4096];
 425                         int ret;
 426
 427                         do {
 428                                 ret = read(sock, buf, sizeof(buf));
 429                         } while (ret == -1 && errno == EINTR);
 430
 431                         if (ret == -1) {
 432                                 log_perror("read");
 433                                 state = CLOSING_SOCKET;
 434                                 continue;
 435                         }
 436
 437                         if (ret == 0) {
 438                                 // This really shouldn't happen...
 439                                 if (!suppress_logging) {
 440                                         log(ERROR, "[%s] Socket unexpectedly closed while reading header",
 441                                                    url.c_str());
 442                                 }
 443                                 state = CLOSING_SOCKET;
 444                                 continue;
 445                         }
 446
 447                         RequestParseStatus status = wait_for_double_newline(&response, buf, ret);
 448
 449                         if (status == RP_OUT_OF_SPACE) {
 450                                 if (!suppress_logging) {
 451                                         log(WARNING, "[%s] Server sent overlong HTTP response!", url.c_str());
 452                                 }
 453                                 state = CLOSING_SOCKET;
 454                                 continue;
 455                         } else if (status == RP_NOT_FINISHED_YET) {
 456                                 continue;
 457                         }
 458
 459                         // OK, so we're fine, but there might be some of the actual data after the response.
 460                         // We'll need to deal with that separately.
 461                         string extra_data;
 462                         if (status == RP_EXTRA_DATA) {
 463                                 char *ptr = static_cast<char *>(
 464                                         memmem(response.data(), response.size(), "\r\n\r\n", 4));
 465                                 assert(ptr != nullptr);
 466                                 extra_data = string(ptr + 4, &response[0] + response.size());
 467                                 response.resize(ptr - response.data());
 468                         }
 469
 470                         if (!parse_response(response)) {
 471                                 state = CLOSING_SOCKET;
 472                                 continue;
 473                         }
 474
 475                         if (!extra_data.empty()) {
 476                                 process_data(&extra_data[0], extra_data.size());
 477                         }
 478
 479                         if (!suppress_logging) {
 480                                 if (encoding == Input::INPUT_ENCODING_RAW) {
 481                                         log(INFO, "[%s] Connected to '%s', receiving raw data.",
 482                                                    url.c_str(), url.c_str());
 483                                 } else {
 484                                         assert(encoding == Input::INPUT_ENCODING_METACUBE);
 485                                         log(INFO, "[%s] Connected to '%s', receiving data.",
 486                                                    url.c_str(), url.c_str());
 487                                 }
 488                         }
 489                         state = RECEIVING_DATA;
 490                         break;
 491                 }
 492                 case RECEIVING_DATA: {
 493                         char buf[4096];
 494                         int ret;
 495
 496                         do {
 497                                 ret = read(sock, buf, sizeof(buf));
 498                         } while (ret == -1 && errno == EINTR);
 499
 500                         if (ret == -1) {
 501                                 log_perror("read");
 502                                 state = CLOSING_SOCKET;
 503                                 continue;
 504                         }
 505
 506                         if (ret == 0) {
 507                                 // This really shouldn't happen...
 508                                 if (!suppress_logging) {
 509                                         log(ERROR, "[%s] Socket unexpectedly closed while reading data",
 510                                                    url.c_str());
 511                                 }
 512                                 state = CLOSING_SOCKET;
 513                                 continue;
 514                         }
 515
 516                         num_connection_attempts = 0;  // Reset, since we have a successful read.
 517                         if (suppress_logging) {
 518                                 // This was suppressed earlier, so print it out now.
 519                                 if (encoding == Input::INPUT_ENCODING_RAW) {
 520                                         log(INFO, "[%s] Connected to '%s', receiving raw data.",
 521                                                    url.c_str(), url.c_str());
 522                                 } else {
 523                                         assert(encoding == Input::INPUT_ENCODING_METACUBE);
 524                                         log(INFO, "[%s] Connected to '%s', receiving data.",
 525                                                    url.c_str(), url.c_str());
 526                                 }
 527                                 suppress_logging = false;
 528                         }
 529
 530                         process_data(buf, ret);
 531                         break;
 532                 }
 533                 case CLOSING_SOCKET: {
 534                         close_socket();
 535                         state = NOT_CONNECTED;
 536                         break;
 537                 }
 538                 default:
 539                         assert(false);
 540                 }
 541
 542                 // If we are still in NOT_CONNECTED, either something went wrong,
 543                 // or the connection just got closed.
 544                 // The earlier steps have already given the error message, if any.
 545                 if (state == NOT_CONNECTED && !should_stop()) {
 546                         if (!suppress_logging) {
 547                                 log(INFO, "[%s] Waiting 0.2 seconds and restarting...", url.c_str());
 548                         }
 549
 550                         if (num_connection_attempts >= 3 && !suppress_logging) {
 551                                 log(INFO, "[%s] %d failed connection attempts, suppressing logging for one minute.",
 552                                         url.c_str(), num_connection_attempts);
 553                                 suppress_logging = true;
 554                         }
 555                         timespec timeout_ts;
 556                         timeout_ts.tv_sec = 0;
 557                         timeout_ts.tv_nsec = 200000000;
 558                         wait_for_wakeup(&timeout_ts);
 559                 }
 560         }
 561 }
 562
 563 void HTTPInput::process_data(char *ptr, size_t bytes)
 564 {
 565         {
 566                 lock_guard<mutex> lock(stats_mutex);
 567                 stats.bytes_received += bytes;
 568         }
 569
 570         if (encoding == Input::INPUT_ENCODING_RAW) {
 571                 for (int stream_index : stream_indices) {
 572                         servers->add_data(stream_index, ptr, bytes, /*metacube_flags=*/0);
 573                 }
 574                 return;
 575         }
 576
 577         assert(encoding == Input::INPUT_ENCODING_METACUBE);
 578         pending_data.insert(pending_data.end(), ptr, ptr + bytes);
 579
 580         for ( ;; ) {
 581                 // If we don't have enough data (yet) for even the Metacube header, just return.
 582                 if (pending_data.size() < sizeof(metacube2_block_header)) {
 583                         return;
 584                 }
 585
 586                 // Make sure we have the Metacube sync header at the start.
 587                 // We may need to skip over junk data (it _should_ not happen, though).
 588                 if (!has_metacube_header) {
 589                         char *ptr = static_cast<char *>(
 590                                 memmem(pending_data.data(), pending_data.size(),
 591                                        METACUBE2_SYNC, strlen(METACUBE2_SYNC)));
 592                         if (ptr == nullptr) {
 593                                 // OK, so we didn't find the sync marker. We know then that
 594                                 // we do not have the _full_ marker in the buffer, but we
 595                                 // could have N-1 bytes. Drop everything before that,
 596                                 // and then give up.
 597                                 drop_pending_data(pending_data.size() - (strlen(METACUBE2_SYNC) - 1));
 598                                 return;
 599                         } else {
 600                                 // Yay, we found the header. Drop everything (if anything) before it.
 601                                 drop_pending_data(ptr - pending_data.data());
 602                                 has_metacube_header = true;
 603
 604                                 // Re-check that we have the entire header; we could have dropped data.
 605                                 if (pending_data.size() < sizeof(metacube2_block_header)) {
 606                                         return;
 607                                 }
 608                         }
 609                 }
 610
 611                 // Now it's safe to read the header.
 612                 metacube2_block_header hdr;
 613                 memcpy(&hdr, pending_data.data(), sizeof(hdr));
 614                 assert(memcmp(hdr.sync, METACUBE2_SYNC, sizeof(hdr.sync)) == 0);
 615                 uint32_t size = ntohl(hdr.size);
 616                 uint16_t flags = ntohs(hdr.flags);
 617                 uint16_t expected_csum = metacube2_compute_crc(&hdr);
 618
 619                 if (expected_csum != ntohs(hdr.csum)) {
 620                         log(WARNING, "[%s] Metacube checksum failed (expected 0x%x, got 0x%x), "
 621                                 "not reading block claiming to be %d bytes (flags=%x).",
 622                                 url.c_str(), expected_csum, ntohs(hdr.csum),
 623                                 size, flags);
 624
 625                         // Drop only the first byte, and let the rest of the code handle resync.
 626                         pending_data.erase(pending_data.begin(), pending_data.begin() + 1);
 627                         has_metacube_header = false;
 628                         continue;
 629                 }
 630                 if (size > 10485760) {
 631                         log(WARNING, "[%s] Metacube block of %d bytes (flags=%x); corrupted header??",
 632                                 url.c_str(), size, flags);
 633                 }
 634
 635                 // See if we have the entire block. If not, wait for more data.
 636                 if (pending_data.size() < sizeof(metacube2_block_header) + size) {
 637                         return;
 638                 }
 639
 640                 // See if this is a metadata block. If so, we don't want to send it on,
 641                 // but rather process it ourselves.
 642                 // TODO: Keep metadata when sending on to other Metacube users.
 643                 if (flags & METACUBE_FLAGS_METADATA) {
 644                         {
 645                                 lock_guard<mutex> lock(stats_mutex);
 646                                 stats.metadata_bytes_received += size;
 647                         }
 648                         process_metacube_metadata_block(hdr, pending_data.data() + sizeof(hdr), size);
 649                 } else {
 650                         // Send this block on to the servers.
 651                         {
 652                                 lock_guard<mutex> lock(stats_mutex);
 653                                 stats.data_bytes_received += size;
 654                         }
 655                         char *inner_data = pending_data.data() + sizeof(metacube2_block_header);
 656                         if (flags & METACUBE_FLAGS_HEADER) {
 657                                 stream_header = string(inner_data, inner_data + size);
 658                                 for (int stream_index : stream_indices) {
 659                                         servers->set_header(stream_index, http_header, stream_header);
 660                                 }
 661                         }
 662                         for (int stream_index : stream_indices) {
 663                                 servers->add_data(stream_index, inner_data, size, flags);
 664                         }
 665                 }
 666
 667                 // Consume the block. This isn't the most efficient way of dealing with things
 668                 // should we have many blocks, but these routines don't need to be too efficient
 669                 // anyway.
 670                 pending_data.erase(pending_data.begin(), pending_data.begin() + sizeof(metacube2_block_header) + size);
 671                 has_metacube_header = false;
 672         }
 673 }
 674
 675 void HTTPInput::drop_pending_data(size_t num_bytes)
 676 {
 677         if (num_bytes == 0) {
 678                 return;
 679         }
 680         log(WARNING, "[%s] Dropping %lld junk bytes; not a Metacube2 stream, or data was dropped from the middle of the stream.",
 681                 url.c_str(), (long long)num_bytes);
 682         assert(pending_data.size() >= num_bytes);
 683         pending_data.erase(pending_data.begin(), pending_data.begin() + num_bytes);
 684 }
 685
 686 void HTTPInput::add_destination(int stream_index)
 687 {
 688         stream_indices.push_back(stream_index);
 689         servers->set_header(stream_index, http_header, stream_header);
 690 }
 691
 692 InputStats HTTPInput::get_stats() const
 693 {
 694         lock_guard<mutex> lock(stats_mutex);
 695         return stats;
 696 }
 697
 698 void HTTPInput::process_metacube_metadata_block(const metacube2_block_header &hdr, const char *payload, uint32_t payload_size)
 699 {
 700         if (payload_size < sizeof(uint64_t)) {
 701                 log(WARNING, "[%s] Undersized Metacube metadata block (%d bytes); corrupted header?",
 702                         url.c_str(), payload_size);
 703                 return;
 704         }
 705
 706         uint64_t type = be64toh(*(const uint64_t *)payload);
 707         if (type != METACUBE_METADATA_TYPE_ENCODER_TIMESTAMP) {
 708                 // Unknown metadata block, ignore.
 709                 return;
 710         }
 711
 712         timespec now;
 713         clock_gettime(CLOCK_REALTIME, &now);
 714
 715         const metacube2_timestamp_packet *pkt = (const metacube2_timestamp_packet *)payload;
 716         if (payload_size != sizeof(*pkt)) {
 717                 log(WARNING, "[%s] Metacube timestamp block of wrong size (%d bytes); ignoring.",
 718                         url.c_str(), payload_size);
 719                 return;
 720         }
 721
 722         double elapsed = now.tv_sec - be64toh(pkt->tv_sec) +
 723                 1e-9 * (now.tv_nsec - long(be64toh(pkt->tv_nsec)));
 724         {
 725                 lock_guard<mutex> lock(stats_mutex);
 726                 stats.latency_sec = elapsed;
 727         }
 728 }