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

   1 #include <assert.h>
   2 #include <errno.h>
   3 #include <getopt.h>
   4 #include <limits.h>
   5 #include <signal.h>
   6 #include <stddef.h>
   7 #include <stdio.h>
   8 #include <stdlib.h>
   9 #include <string.h>
  10 #include <sys/time.h>
  11 #include <sys/wait.h>
  12 #include <unistd.h>
  13 #include <map>
  14 #include <set>
  15 #include <string>
  16 #include <utility>
  17 #include <vector>
  18
  19 #include "acceptor.h"
  20 #include "accesslog.h"
  21 #include "config.h"
  22 #include "input.h"
  23 #include "input_stats.h"
  24 #include "log.h"
  25 #include "sa_compare.h"
  26 #include "serverpool.h"
  27 #include "state.pb.h"
  28 #include "stats.h"
  29 #include "stream.h"
  30 #include "util.h"
  31 #include "version.h"
  32
  33 using namespace std;
  34
  35 AccessLogThread *access_log = NULL;
  36 ServerPool *servers = NULL;
  37 volatile bool hupped = false;
  38 volatile bool stopped = false;
  39
  40 struct InputWithRefcount {
  41         Input *input;
  42         int refcount;
  43 };
  44
  45 void hup(int signum)
  46 {
  47         hupped = true;
  48         if (signum == SIGINT) {
  49                 stopped = true;
  50         }
  51 }
  52
  53 void do_nothing(int signum)
  54 {
  55 }
  56
  57 CubemapStateProto collect_state(const timeval &serialize_start,
  58                                 const vector<Acceptor *> acceptors,
  59                                 const multimap<string, InputWithRefcount> inputs,
  60                                 ServerPool *servers)
  61 {
  62         CubemapStateProto state = servers->serialize();  // Fills streams() and clients().
  63         state.set_serialize_start_sec(serialize_start.tv_sec);
  64         state.set_serialize_start_usec(serialize_start.tv_usec);
  65
  66         for (size_t i = 0; i < acceptors.size(); ++i) {
  67                 state.add_acceptors()->MergeFrom(acceptors[i]->serialize());
  68         }
  69
  70         for (multimap<string, InputWithRefcount>::const_iterator input_it = inputs.begin();
  71              input_it != inputs.end();
  72              ++input_it) {
  73                 state.add_inputs()->MergeFrom(input_it->second.input->serialize());
  74         }
  75
  76         return state;
  77 }
  78
  79 // Find all port statements in the configuration file, and create acceptors for htem.
  80 vector<Acceptor *> create_acceptors(
  81         const Config &config,
  82         map<sockaddr_in6, Acceptor *, Sockaddr6Compare> *deserialized_acceptors)
  83 {
  84         vector<Acceptor *> acceptors;
  85         for (unsigned i = 0; i < config.acceptors.size(); ++i) {
  86                 const AcceptorConfig &acceptor_config = config.acceptors[i];
  87                 Acceptor *acceptor = NULL;
  88                 map<sockaddr_in6, Acceptor *, Sockaddr6Compare>::iterator deserialized_acceptor_it =
  89                         deserialized_acceptors->find(acceptor_config.addr);
  90                 if (deserialized_acceptor_it != deserialized_acceptors->end()) {
  91                         acceptor = deserialized_acceptor_it->second;
  92                         deserialized_acceptors->erase(deserialized_acceptor_it);
  93                 } else {
  94                         int server_sock = create_server_socket(acceptor_config.addr, TCP_SOCKET);
  95                         acceptor = new Acceptor(server_sock, acceptor_config.addr);
  96                 }
  97                 acceptor->run();
  98                 acceptors.push_back(acceptor);
  99         }
 100
 101         // Close all acceptors that are no longer in the configuration file.
 102         for (map<sockaddr_in6, Acceptor *, Sockaddr6Compare>::iterator
 103                  acceptor_it = deserialized_acceptors->begin();
 104              acceptor_it != deserialized_acceptors->end();
 105              ++acceptor_it) {
 106                 acceptor_it->second->close_socket();
 107                 delete acceptor_it->second;
 108         }
 109
 110         return acceptors;
 111 }
 112
 113 void create_config_input(const string &src, multimap<string, InputWithRefcount> *inputs)
 114 {
 115         if (src.empty()) {
 116                 return;
 117         }
 118         if (inputs->count(src) != 0) {
 119                 return;
 120         }
 121
 122         InputWithRefcount iwr;
 123         iwr.input = create_input(src);
 124         if (iwr.input == NULL) {
 125                 log(ERROR, "did not understand URL '%s', clients will not get any data.",
 126                         src.c_str());
 127                 return;
 128         }
 129         iwr.refcount = 0;
 130         inputs->insert(make_pair(src, iwr));
 131 }
 132
 133 // Find all streams in the configuration file, and create inputs for them.
 134 void create_config_inputs(const Config &config, multimap<string, InputWithRefcount> *inputs)
 135 {
 136         for (unsigned i = 0; i < config.streams.size(); ++i) {
 137                 const StreamConfig &stream_config = config.streams[i];
 138                 if (stream_config.src != "delete") {
 139                         create_config_input(stream_config.src, inputs);
 140                 }
 141         }
 142         for (unsigned i = 0; i < config.udpstreams.size(); ++i) {
 143                 const UDPStreamConfig &udpstream_config = config.udpstreams[i];
 144                 create_config_input(udpstream_config.src, inputs);
 145         }
 146 }
 147
 148 void create_streams(const Config &config,
 149                     const set<string> &deserialized_urls,
 150                     multimap<string, InputWithRefcount> *inputs)
 151 {
 152         // HTTP streams.
 153         set<string> expecting_urls = deserialized_urls;
 154         for (unsigned i = 0; i < config.streams.size(); ++i) {
 155                 const StreamConfig &stream_config = config.streams[i];
 156                 int stream_index;
 157
 158                 expecting_urls.erase(stream_config.url);
 159
 160                 // Special-case deleted streams; they were never deserialized in the first place,
 161                 // so just ignore them.
 162                 if (stream_config.src == "delete") {
 163                         continue;
 164                 }
 165
 166                 if (deserialized_urls.count(stream_config.url) == 0) {
 167                         stream_index = servers->add_stream(stream_config.url,
 168                                                            stream_config.backlog_size,
 169                                                            Stream::Encoding(stream_config.encoding));
 170                 } else {
 171                         stream_index = servers->lookup_stream_by_url(stream_config.url);
 172                         assert(stream_index != -1);
 173                         servers->set_backlog_size(stream_index, stream_config.backlog_size);
 174                         servers->set_encoding(stream_index,
 175                                               Stream::Encoding(stream_config.encoding));
 176                 }
 177
 178                 servers->set_pacing_rate(stream_index, stream_config.pacing_rate);
 179
 180                 string src = stream_config.src;
 181                 if (!src.empty()) {
 182                         multimap<string, InputWithRefcount>::iterator input_it = inputs->find(src);
 183                         if (input_it != inputs->end()) {
 184                                 input_it->second.input->add_destination(stream_index);
 185                                 ++input_it->second.refcount;
 186                         }
 187                 }
 188         }
 189
 190         // Warn about any streams servers we've lost.
 191         for (set<string>::const_iterator stream_it = expecting_urls.begin();
 192              stream_it != expecting_urls.end();
 193              ++stream_it) {
 194                 string url = *stream_it;
 195                 log(WARNING, "stream '%s' disappeared from the configuration file. "
 196                              "It will not be deleted, but clients will not get any new inputs. "
 197                              "If you really meant to delete it, set src=delete and reload.",
 198                              url.c_str());
 199         }
 200
 201         // UDP streams.
 202         for (unsigned i = 0; i < config.udpstreams.size(); ++i) {
 203                 const UDPStreamConfig &udpstream_config = config.udpstreams[i];
 204                 int stream_index = servers->add_udpstream(
 205                         udpstream_config.dst,
 206                         udpstream_config.pacing_rate,
 207                         udpstream_config.ttl,
 208                         udpstream_config.multicast_iface_index);
 209
 210                 string src = udpstream_config.src;
 211                 if (!src.empty()) {
 212                         multimap<string, InputWithRefcount>::iterator input_it = inputs->find(src);
 213                         assert(input_it != inputs->end());
 214                         input_it->second.input->add_destination(stream_index);
 215                         ++input_it->second.refcount;
 216                 }
 217         }
 218 }
 219
 220 void open_logs(const vector<LogConfig> &log_destinations)
 221 {
 222         for (size_t i = 0; i < log_destinations.size(); ++i) {
 223                 if (log_destinations[i].type == LogConfig::LOG_TYPE_FILE) {
 224                         add_log_destination_file(log_destinations[i].filename);
 225                 } else if (log_destinations[i].type == LogConfig::LOG_TYPE_CONSOLE) {
 226                         add_log_destination_console();
 227                 } else if (log_destinations[i].type == LogConfig::LOG_TYPE_SYSLOG) {
 228                         add_log_destination_syslog();
 229                 } else {
 230                         assert(false);
 231                 }
 232         }
 233         start_logging();
 234 }
 235
 236 bool dry_run_config(const std::string &argv0, const std::string &config_filename)
 237 {
 238         char *argv0_copy = strdup(argv0.c_str());
 239         char *config_filename_copy = strdup(config_filename.c_str());
 240
 241         pid_t pid = fork();
 242         switch (pid) {
 243         case -1:
 244                 log_perror("fork()");
 245                 free(argv0_copy);
 246                 free(config_filename_copy);
 247                 return false;
 248         case 0:
 249                 // Child.
 250                 execlp(argv0_copy, argv0_copy, "--test-config", config_filename_copy, NULL);
 251                 log_perror(argv0_copy);
 252                 _exit(1);
 253         default:
 254                 // Parent.
 255                 break;
 256         }
 257
 258         free(argv0_copy);
 259         free(config_filename_copy);
 260
 261         int status;
 262         pid_t err;
 263         do {
 264                 err = waitpid(pid, &status, 0);
 265         } while (err == -1 && errno == EINTR);
 266
 267         if (err == -1) {
 268                 log_perror("waitpid()");
 269                 return false;
 270         }
 271
 272         return (WIFEXITED(status) && WEXITSTATUS(status) == 0);
 273 }
 274
 275 void find_deleted_streams(const Config &config, set<string> *deleted_urls)
 276 {
 277         for (unsigned i = 0; i < config.streams.size(); ++i) {
 278                 const StreamConfig &stream_config = config.streams[i];
 279                 if (stream_config.src == "delete") {
 280                         log(INFO, "Deleting stream '%s'.", stream_config.url.c_str());
 281                         deleted_urls->insert(stream_config.url);
 282                 }
 283         }
 284 }
 285
 286 int main(int argc, char **argv)
 287 {
 288         signal(SIGHUP, hup);
 289         signal(SIGINT, hup);
 290         signal(SIGUSR1, do_nothing);  // Used in internal signalling.
 291         signal(SIGPIPE, SIG_IGN);
 292
 293         // Parse options.
 294         int state_fd = -1;
 295         bool test_config = false;
 296         for ( ;; ) {
 297                 static const option long_options[] = {
 298                         { "state", required_argument, 0, 's' },
 299                         { "test-config", no_argument, 0, 't' },
 300                         { 0, 0, 0, 0 }
 301                 };
 302                 int option_index = 0;
 303                 int c = getopt_long(argc, argv, "s:t", long_options, &option_index);
 304
 305                 if (c == -1) {
 306                         break;
 307                 }
 308                 switch (c) {
 309                 case 's':
 310                         state_fd = atoi(optarg);
 311                         break;
 312                 case 't':
 313                         test_config = true;
 314                         break;
 315                 default:
 316                         fprintf(stderr, "Unknown option '%s'\n", argv[option_index]);
 317                         exit(1);
 318                 }
 319         }
 320
 321         string config_filename = "cubemap.config";
 322         if (optind < argc) {
 323                 config_filename = argv[optind++];
 324         }
 325
 326         // Canonicalize argv[0] and config_filename.
 327         char argv0_canon[PATH_MAX];
 328         char config_filename_canon[PATH_MAX];
 329
 330         if (realpath("/proc/self/exe", argv0_canon) == NULL) {
 331                 log_perror(argv[0]);
 332                 exit(1);
 333         }
 334         if (realpath(config_filename.c_str(), config_filename_canon) == NULL) {
 335                 log_perror(config_filename.c_str());
 336                 exit(1);
 337         }
 338
 339         // Now parse the configuration file.
 340         Config config;
 341         if (!parse_config(config_filename_canon, &config)) {
 342                 exit(1);
 343         }
 344         if (test_config) {
 345                 exit(0);
 346         }
 347
 348         // Ideally we'd like to daemonize only when we've started up all threads etc.,
 349         // but daemon() forks, which is not good in multithreaded software, so we'll
 350         // have to do it here.
 351         if (config.daemonize) {
 352                 if (daemon(0, 0) == -1) {
 353                         log_perror("daemon");
 354                         exit(1);
 355                 }
 356         }
 357
 358 start:
 359         // Open logs as soon as possible.
 360         open_logs(config.log_destinations);
 361
 362         log(INFO, "Cubemap " SERVER_VERSION " starting.");
 363         if (config.access_log_file.empty()) {
 364                 // Create a dummy logger.
 365                 access_log = new AccessLogThread();
 366         } else {
 367                 access_log = new AccessLogThread(config.access_log_file);
 368         }
 369         access_log->run();
 370
 371         servers = new ServerPool(config.num_servers);
 372
 373         // Find all the streams that are to be deleted.
 374         set<string> deleted_urls;
 375         find_deleted_streams(config, &deleted_urls);
 376
 377         CubemapStateProto loaded_state;
 378         struct timeval serialize_start;
 379         set<string> deserialized_urls;
 380         map<sockaddr_in6, Acceptor *, Sockaddr6Compare> deserialized_acceptors;
 381         multimap<string, InputWithRefcount> inputs;  // multimap due to older versions without deduplication.
 382         if (state_fd != -1) {
 383                 log(INFO, "Deserializing state from previous process...");
 384                 string serialized;
 385                 if (!read_tempfile_and_close(state_fd, &serialized)) {
 386                         exit(1);
 387                 }
 388                 if (!loaded_state.ParseFromString(serialized)) {
 389                         log(ERROR, "Failed deserialization of state.");
 390                         exit(1);
 391                 }
 392
 393                 serialize_start.tv_sec = loaded_state.serialize_start_sec();
 394                 serialize_start.tv_usec = loaded_state.serialize_start_usec();
 395
 396                 // Deserialize the streams.
 397                 map<string, string> stream_headers_for_url;  // See below.
 398                 for (int i = 0; i < loaded_state.streams_size(); ++i) {
 399                         const StreamProto &stream = loaded_state.streams(i);
 400
 401                         if (deleted_urls.count(stream.url()) != 0) {
 402                                 // Delete the stream backlogs.
 403                                 for (int j = 0; j < stream.data_fds_size(); ++j) {
 404                                         safe_close(stream.data_fds(j));
 405                                 }
 406                         } else {
 407                                 vector<int> data_fds;
 408                                 for (int j = 0; j < stream.data_fds_size(); ++j) {
 409                                         data_fds.push_back(stream.data_fds(j));
 410                                 }
 411
 412                                 servers->add_stream_from_serialized(stream, data_fds);
 413                                 deserialized_urls.insert(stream.url());
 414
 415                                 stream_headers_for_url.insert(make_pair(stream.url(), stream.stream_header()));
 416                         }
 417                 }
 418
 419                 // Deserialize the inputs. Note that we don't actually add them to any stream yet.
 420                 for (int i = 0; i < loaded_state.inputs_size(); ++i) {
 421                         InputProto serialized_input = loaded_state.inputs(i);
 422
 423                         InputWithRefcount iwr;
 424                         iwr.input = create_input(serialized_input);
 425                         iwr.refcount = 0;
 426                         inputs.insert(make_pair(serialized_input.url(), iwr));
 427                 }
 428
 429                 // Deserialize the acceptors.
 430                 for (int i = 0; i < loaded_state.acceptors_size(); ++i) {
 431                         sockaddr_in6 sin6 = ExtractAddressFromAcceptorProto(loaded_state.acceptors(i));
 432                         deserialized_acceptors.insert(make_pair(
 433                                 sin6,
 434                                 new Acceptor(loaded_state.acceptors(i))));
 435                 }
 436
 437                 log(INFO, "Deserialization done.");
 438         }
 439
 440         // Add any new inputs coming from the config.
 441         create_config_inputs(config, &inputs);
 442
 443         // Find all streams in the configuration file, create them, and connect to the inputs.
 444         create_streams(config, deserialized_urls, &inputs);
 445         vector<Acceptor *> acceptors = create_acceptors(config, &deserialized_acceptors);
 446
 447         // Put back the existing clients. It doesn't matter which server we
 448         // allocate them to, so just do round-robin.
 449         for (int i = 0; i < loaded_state.clients_size(); ++i) {
 450                 if (deleted_urls.count(loaded_state.clients(i).url()) != 0) {
 451                         safe_close(loaded_state.clients(i).sock());
 452                 } else {
 453                         servers->add_client_from_serialized(loaded_state.clients(i));
 454                 }
 455         }
 456
 457         servers->run();
 458
 459         // Now delete all inputs that are longer in use, and start the others.
 460         for (multimap<string, InputWithRefcount>::iterator input_it = inputs.begin();
 461              input_it != inputs.end(); ) {
 462                 if (input_it->second.refcount == 0) {
 463                         log(WARNING, "Input '%s' no longer in use, closing.",
 464                             input_it->first.c_str());
 465                         input_it->second.input->close_socket();
 466                         delete input_it->second.input;
 467                         inputs.erase(input_it++);
 468                 } else {
 469                         input_it->second.input->run();
 470                         ++input_it;
 471                 }
 472         }
 473
 474         // Start writing statistics.
 475         StatsThread *stats_thread = NULL;
 476         if (!config.stats_file.empty()) {
 477                 stats_thread = new StatsThread(config.stats_file, config.stats_interval);
 478                 stats_thread->run();
 479         }
 480
 481         InputStatsThread *input_stats_thread = NULL;
 482         if (!config.input_stats_file.empty()) {
 483                 vector<Input*> inputs_no_refcount;
 484                 for (multimap<string, InputWithRefcount>::iterator input_it = inputs.begin();
 485                      input_it != inputs.end(); ++input_it) {
 486                         inputs_no_refcount.push_back(input_it->second.input);
 487                 }
 488
 489                 input_stats_thread = new InputStatsThread(config.input_stats_file, config.input_stats_interval, inputs_no_refcount);
 490                 input_stats_thread->run();
 491         }
 492
 493         struct timeval server_start;
 494         gettimeofday(&server_start, NULL);
 495         if (state_fd != -1) {
 496                 // Measure time from we started deserializing (below) to now, when basically everything
 497                 // is up and running. This is, in other words, a conservative estimate of how long our
 498                 // “glitch” period was, not counting of course reconnects if the configuration changed.
 499                 double glitch_time = server_start.tv_sec - serialize_start.tv_sec +
 500                         1e-6 * (server_start.tv_usec - serialize_start.tv_usec);
 501                 log(INFO, "Re-exec happened in approx. %.0f ms.", glitch_time * 1000.0);
 502         }
 503
 504         while (!hupped) {
 505                 usleep(100000);
 506         }
 507
 508         // OK, we've been HUPed. Time to shut down everything, serialize, and re-exec.
 509         gettimeofday(&serialize_start, NULL);
 510
 511         if (input_stats_thread != NULL) {
 512                 input_stats_thread->stop();
 513                 delete input_stats_thread;
 514         }
 515         if (stats_thread != NULL) {
 516                 stats_thread->stop();
 517                 delete stats_thread;
 518         }
 519         for (size_t i = 0; i < acceptors.size(); ++i) {
 520                 acceptors[i]->stop();
 521         }
 522         for (multimap<string, InputWithRefcount>::iterator input_it = inputs.begin();
 523              input_it != inputs.end();
 524              ++input_it) {
 525                 input_it->second.input->stop();
 526         }
 527         servers->stop();
 528
 529         CubemapStateProto state;
 530         if (stopped) {
 531                 log(INFO, "Shutting down.");
 532         } else {
 533                 log(INFO, "Serializing state and re-execing...");
 534                 state = collect_state(
 535                         serialize_start, acceptors, inputs, servers);
 536                 string serialized;
 537                 state.SerializeToString(&serialized);
 538                 state_fd = make_tempfile(serialized);
 539                 if (state_fd == -1) {
 540                         exit(1);
 541                 }
 542         }
 543         delete servers;
 544
 545         access_log->stop();
 546         delete access_log;
 547         shut_down_logging();
 548
 549         if (stopped) {
 550                 exit(0);
 551         }
 552
 553         // OK, so the signal was SIGHUP. Check that the new config is okay, then exec the new binary.
 554         if (!dry_run_config(argv0_canon, config_filename_canon)) {
 555                 open_logs(config.log_destinations);
 556                 log(ERROR, "%s --test-config failed. Restarting old version instead of new.", argv[0]);
 557                 hupped = false;
 558                 shut_down_logging();
 559                 goto start;
 560         }
 561
 562         char buf[16];
 563         sprintf(buf, "%d", state_fd);
 564
 565         for ( ;; ) {
 566                 execlp(argv0_canon, argv0_canon, config_filename_canon, "--state", buf, NULL);
 567                 open_logs(config.log_destinations);
 568                 log_perror("execlp");
 569                 log(ERROR, "re-exec of %s failed. Waiting 0.2 seconds and trying again...", argv0_canon);
 570                 shut_down_logging();
 571                 usleep(200000);
 572         }
 573 }