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