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