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 "log.h"
  24 #include "markpool.h"
  25 #include "serverpool.h"
  26 #include "state.pb.h"
  27 #include "stats.h"
  28 #include "stream.h"
  29 #include "util.h"
  30 #include "version.h"
  31
  32 using namespace std;
  33
  34 AccessLogThread *access_log = NULL;
  35 ServerPool *servers = NULL;
  36 vector<MarkPool *> mark_pools;
  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<int, Acceptor *> *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<int, Acceptor *>::iterator deserialized_acceptor_it =
  89                         deserialized_acceptors->find(acceptor_config.port);
  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.port, TCP_SOCKET);
  95                         acceptor = new Acceptor(server_sock, acceptor_config.port);
  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<int, Acceptor *>::iterator acceptor_it = deserialized_acceptors->begin();
 103              acceptor_it != deserialized_acceptors->end();
 104              ++acceptor_it) {
 105                 acceptor_it->second->close_socket();
 106                 delete acceptor_it->second;
 107         }
 108
 109         return acceptors;
 110 }
 111
 112 void create_config_input(const string &src, multimap<string, InputWithRefcount> *inputs)
 113 {
 114         if (src.empty()) {
 115                 return;
 116         }
 117         if (inputs->count(src) != 0) {
 118                 return;
 119         }
 120
 121         InputWithRefcount iwr;
 122         iwr.input = create_input(src);
 123         if (iwr.input == NULL) {
 124                 log(ERROR, "did not understand URL '%s', clients will not get any data.",
 125                         src.c_str());
 126                 return;
 127         }
 128         iwr.refcount = 0;
 129         inputs->insert(make_pair(src, iwr));
 130 }
 131
 132 // Find all streams in the configuration file, and create inputs for them.
 133 void create_config_inputs(const Config &config, multimap<string, InputWithRefcount> *inputs)
 134 {
 135         for (unsigned i = 0; i < config.streams.size(); ++i) {
 136                 const StreamConfig &stream_config = config.streams[i];
 137                 create_config_input(stream_config.src, inputs);
 138         }
 139         for (unsigned i = 0; i < config.udpstreams.size(); ++i) {
 140                 const UDPStreamConfig &udpstream_config = config.udpstreams[i];
 141                 create_config_input(udpstream_config.src, inputs);
 142         }
 143 }
 144
 145 void create_streams(const Config &config,
 146                     const set<string> &deserialized_urls,
 147                     multimap<string, InputWithRefcount> *inputs)
 148 {
 149         for (unsigned i = 0; i < config.mark_pools.size(); ++i) {
 150                 const MarkPoolConfig &mp_config = config.mark_pools[i];
 151                 mark_pools.push_back(new MarkPool(mp_config.from, mp_config.to));
 152         }
 153
 154         // HTTP streams.
 155         set<string> expecting_urls = deserialized_urls;
 156         for (unsigned i = 0; i < config.streams.size(); ++i) {
 157                 const StreamConfig &stream_config = config.streams[i];
 158                 int stream_index;
 159                 if (deserialized_urls.count(stream_config.url) == 0) {
 160                         stream_index = servers->add_stream(stream_config.url,
 161                                                            stream_config.backlog_size,
 162                                                            Stream::Encoding(stream_config.encoding));
 163                 } else {
 164                         stream_index = servers->lookup_stream_by_url(stream_config.url);
 165                         assert(stream_index != -1);
 166                         servers->set_backlog_size(stream_index, stream_config.backlog_size);
 167                         servers->set_encoding(stream_index,
 168                                               Stream::Encoding(stream_config.encoding));
 169                 }
 170                 expecting_urls.erase(stream_config.url);
 171
 172                 if (stream_config.mark_pool != -1) {
 173                         servers->set_mark_pool(stream_index, mark_pools[stream_config.mark_pool]);
 174                 }
 175
 176                 string src = stream_config.src;
 177                 if (!src.empty()) {
 178                         multimap<string, InputWithRefcount>::iterator input_it = inputs->find(src);
 179                         assert(input_it != inputs->end());
 180                         input_it->second.input->add_destination(stream_index);
 181                         ++input_it->second.refcount;
 182                 }
 183         }
 184
 185         // Warn about any HTTP servers we've lost.
 186         // TODO: Make an option (delete=yes?) to actually shut down streams.
 187         for (set<string>::const_iterator stream_it = expecting_urls.begin();
 188              stream_it != expecting_urls.end();
 189              ++stream_it) {
 190                 string url = *stream_it;
 191                 log(WARNING, "stream '%s' disappeared from the configuration file. "
 192                              "It will not be deleted, but clients will not get any new inputs.",
 193                              url.c_str());
 194         }
 195
 196         // UDP streams.
 197         for (unsigned i = 0; i < config.udpstreams.size(); ++i) {
 198                 const UDPStreamConfig &udpstream_config = config.udpstreams[i];
 199                 MarkPool *mark_pool = NULL;
 200                 if (udpstream_config.mark_pool != -1) {
 201                         mark_pool = mark_pools[udpstream_config.mark_pool];
 202                 }
 203                 int stream_index = servers->add_udpstream(udpstream_config.dst, mark_pool);
 204
 205                 string src = udpstream_config.src;
 206                 if (!src.empty()) {
 207                         multimap<string, InputWithRefcount>::iterator input_it = inputs->find(src);
 208                         assert(input_it != inputs->end());
 209                         input_it->second.input->add_destination(stream_index);
 210                         ++input_it->second.refcount;
 211                 }
 212         }
 213 }
 214
 215 void open_logs(const vector<LogConfig> &log_destinations)
 216 {
 217         for (size_t i = 0; i < log_destinations.size(); ++i) {
 218                 if (log_destinations[i].type == LogConfig::LOG_TYPE_FILE) {
 219                         add_log_destination_file(log_destinations[i].filename);
 220                 } else if (log_destinations[i].type == LogConfig::LOG_TYPE_CONSOLE) {
 221                         add_log_destination_console();
 222                 } else if (log_destinations[i].type == LogConfig::LOG_TYPE_SYSLOG) {
 223                         add_log_destination_syslog();
 224                 } else {
 225                         assert(false);
 226                 }
 227         }
 228         start_logging();
 229 }
 230
 231 bool dry_run_config(const std::string &argv0, const std::string &config_filename)
 232 {
 233         char *argv0_copy = strdup(argv0.c_str());
 234         char *config_filename_copy = strdup(config_filename.c_str());
 235
 236         pid_t pid = fork();
 237         switch (pid) {
 238         case -1:
 239                 log_perror("fork()");
 240                 free(argv0_copy);
 241                 free(config_filename_copy);
 242                 return false;
 243         case 0:
 244                 // Child.
 245                 execlp(argv0_copy, argv0_copy, "--test-config", config_filename_copy, NULL);
 246                 log_perror(argv0_copy);
 247                 _exit(1);
 248         default:
 249                 // Parent.
 250                 break;
 251         }
 252
 253         free(argv0_copy);
 254         free(config_filename_copy);
 255
 256         int status;
 257         pid_t err;
 258         do {
 259                 err = waitpid(pid, &status, 0);
 260         } while (err == -1 && errno == EINTR);
 261
 262         if (err == -1) {
 263                 log_perror("waitpid()");
 264                 return false;
 265         }
 266
 267         return (WIFEXITED(status) && WEXITSTATUS(status) == 0);
 268 }
 269
 270 int main(int argc, char **argv)
 271 {
 272         signal(SIGHUP, hup);
 273         signal(SIGINT, hup);
 274         signal(SIGUSR1, do_nothing);  // Used in internal signalling.
 275         signal(SIGPIPE, SIG_IGN);
 276
 277         // Parse options.
 278         int state_fd = -1;
 279         bool test_config = false;
 280         for ( ;; ) {
 281                 static const option long_options[] = {
 282                         { "state", required_argument, 0, 's' },
 283                         { "test-config", no_argument, 0, 't' },
 284                         { 0, 0, 0, 0 }
 285                 };
 286                 int option_index = 0;
 287                 int c = getopt_long(argc, argv, "s:t", long_options, &option_index);
 288
 289                 if (c == -1) {
 290                         break;
 291                 }
 292                 switch (c) {
 293                 case 's':
 294                         state_fd = atoi(optarg);
 295                         break;
 296                 case 't':
 297                         test_config = true;
 298                         break;
 299                 default:
 300                         fprintf(stderr, "Unknown option '%s'\n", argv[option_index]);
 301                         exit(1);
 302                 }
 303         }
 304
 305         string config_filename = "cubemap.config";
 306         if (optind < argc) {
 307                 config_filename = argv[optind++];
 308         }
 309
 310         // Canonicalize argv[0] and config_filename.
 311         char argv0_canon[PATH_MAX];
 312         char config_filename_canon[PATH_MAX];
 313
 314         if (realpath(argv[0], argv0_canon) == NULL) {
 315                 log_perror(argv[0]);
 316                 exit(1);
 317         }
 318         if (realpath(config_filename.c_str(), config_filename_canon) == NULL) {
 319                 log_perror(config_filename.c_str());
 320                 exit(1);
 321         }
 322
 323         // Now parse the configuration file.
 324         Config config;
 325         if (!parse_config(config_filename_canon, &config)) {
 326                 exit(1);
 327         }
 328         if (test_config) {
 329                 exit(0);
 330         }
 331
 332         // Ideally we'd like to daemonize only when we've started up all threads etc.,
 333         // but daemon() forks, which is not good in multithreaded software, so we'll
 334         // have to do it here.
 335         if (config.daemonize) {
 336                 if (daemon(0, 0) == -1) {
 337                         log_perror("daemon");
 338                         exit(1);
 339                 }
 340         }
 341
 342 start:
 343         // Open logs as soon as possible.
 344         open_logs(config.log_destinations);
 345
 346         log(INFO, "Cubemap " SERVER_VERSION " starting.");
 347         if (config.access_log_file.empty()) {
 348                 // Create a dummy logger.
 349                 access_log = new AccessLogThread();
 350         } else {
 351                 access_log = new AccessLogThread(config.access_log_file);
 352         }
 353         access_log->run();
 354
 355         servers = new ServerPool(config.num_servers);
 356
 357         CubemapStateProto loaded_state;
 358         struct timeval serialize_start;
 359         set<string> deserialized_urls;
 360         map<int, Acceptor *> deserialized_acceptors;
 361         multimap<string, InputWithRefcount> inputs;  // multimap due to older versions without deduplication.
 362         if (state_fd != -1) {
 363                 log(INFO, "Deserializing state from previous process...");
 364                 string serialized;
 365                 if (!read_tempfile(state_fd, &serialized)) {
 366                         exit(1);
 367                 }
 368                 if (!loaded_state.ParseFromString(serialized)) {
 369                         log(ERROR, "Failed deserialization of state.");
 370                         exit(1);
 371                 }
 372
 373                 serialize_start.tv_sec = loaded_state.serialize_start_sec();
 374                 serialize_start.tv_usec = loaded_state.serialize_start_usec();
 375
 376                 // Deserialize the streams.
 377                 for (int i = 0; i < loaded_state.streams_size(); ++i) {
 378                         const StreamProto &stream = loaded_state.streams(i);
 379
 380                         vector<int> data_fds;
 381                         for (int j = 0; j < stream.data_fds_size(); ++j) {
 382                                 data_fds.push_back(stream.data_fds(j));
 383                         }
 384
 385                         // Older versions stored the data once in the protobuf instead of
 386                         // sending around file descriptors.
 387                         if (data_fds.empty() && stream.has_data()) {
 388                                 data_fds.push_back(make_tempfile(stream.data()));
 389                         }
 390
 391                         servers->add_stream_from_serialized(stream, data_fds);
 392                         deserialized_urls.insert(stream.url());
 393                 }
 394
 395                 // Deserialize the inputs. Note that we don't actually add them to any stream yet.
 396                 for (int i = 0; i < loaded_state.inputs_size(); ++i) {
 397                         InputWithRefcount iwr;
 398                         iwr.input = create_input(loaded_state.inputs(i));
 399                         iwr.refcount = 0;
 400                         inputs.insert(make_pair(loaded_state.inputs(i).url(), iwr));
 401                 }
 402
 403                 // Deserialize the acceptors.
 404                 for (int i = 0; i < loaded_state.acceptors_size(); ++i) {
 405                         deserialized_acceptors.insert(make_pair(
 406                                 loaded_state.acceptors(i).port(),
 407                                 new Acceptor(loaded_state.acceptors(i))));
 408                 }
 409
 410                 log(INFO, "Deserialization done.");
 411         }
 412
 413         // Add any new inputs coming from the config.
 414         create_config_inputs(config, &inputs);
 415
 416         // Find all streams in the configuration file, create them, and connect to the inputs.
 417         create_streams(config, deserialized_urls, &inputs);
 418         vector<Acceptor *> acceptors = create_acceptors(config, &deserialized_acceptors);
 419
 420         // Put back the existing clients. It doesn't matter which server we
 421         // allocate them to, so just do round-robin. However, we need to add
 422         // them after the mark pools have been set up.
 423         for (int i = 0; i < loaded_state.clients_size(); ++i) {
 424                 servers->add_client_from_serialized(loaded_state.clients(i));
 425         }
 426
 427         servers->run();
 428
 429         // Now delete all inputs that are longer in use, and start the others.
 430         for (multimap<string, InputWithRefcount>::iterator input_it = inputs.begin();
 431              input_it != inputs.end(); ) {
 432                 if (input_it->second.refcount == 0) {
 433                         log(WARNING, "Input '%s' no longer in use, closing.",
 434                             input_it->first.c_str());
 435                         input_it->second.input->close_socket();
 436                         delete input_it->second.input;
 437                         inputs.erase(input_it++);
 438                 } else {
 439                         input_it->second.input->run();
 440                         ++input_it;
 441                 }
 442         }
 443
 444         // Start writing statistics.
 445         StatsThread *stats_thread = NULL;
 446         if (!config.stats_file.empty()) {
 447                 stats_thread = new StatsThread(config.stats_file, config.stats_interval);
 448                 stats_thread->run();
 449         }
 450
 451         struct timeval server_start;
 452         gettimeofday(&server_start, NULL);
 453         if (state_fd != -1) {
 454                 // Measure time from we started deserializing (below) to now, when basically everything
 455                 // is up and running. This is, in other words, a conservative estimate of how long our
 456                 // “glitch” period was, not counting of course reconnects if the configuration changed.
 457                 double glitch_time = server_start.tv_sec - serialize_start.tv_sec +
 458                         1e-6 * (server_start.tv_usec - serialize_start.tv_usec);
 459                 log(INFO, "Re-exec happened in approx. %.0f ms.", glitch_time * 1000.0);
 460         }
 461
 462         while (!hupped) {
 463                 usleep(100000);
 464         }
 465
 466         // OK, we've been HUPed. Time to shut down everything, serialize, and re-exec.
 467         gettimeofday(&serialize_start, NULL);
 468
 469         if (stats_thread != NULL) {
 470                 stats_thread->stop();
 471                 delete stats_thread;
 472         }
 473         for (size_t i = 0; i < acceptors.size(); ++i) {
 474                 acceptors[i]->stop();
 475         }
 476         for (multimap<string, InputWithRefcount>::iterator input_it = inputs.begin();
 477              input_it != inputs.end();
 478              ++input_it) {
 479                 input_it->second.input->stop();
 480         }
 481         servers->stop();
 482
 483         CubemapStateProto state;
 484         if (stopped) {
 485                 log(INFO, "Shutting down.");
 486         } else {
 487                 log(INFO, "Serializing state and re-execing...");
 488                 state = collect_state(
 489                         serialize_start, acceptors, inputs, servers);
 490                 string serialized;
 491                 state.SerializeToString(&serialized);
 492                 state_fd = make_tempfile(serialized);
 493                 if (state_fd == -1) {
 494                         exit(1);
 495                 }
 496         }
 497         delete servers;
 498
 499         for (unsigned i = 0; i < mark_pools.size(); ++i) {
 500                 delete mark_pools[i];
 501         }
 502         mark_pools.clear();
 503
 504         access_log->stop();
 505         delete access_log;
 506         shut_down_logging();
 507
 508         if (stopped) {
 509                 exit(0);
 510         }
 511
 512         // OK, so the signal was SIGHUP. Check that the new config is okay, then exec the new binary.
 513         if (!dry_run_config(argv0_canon, config_filename_canon)) {
 514                 open_logs(config.log_destinations);
 515                 log(ERROR, "%s --test-config failed. Restarting old version instead of new.", argv[0]);
 516                 hupped = false;
 517                 shut_down_logging();
 518                 goto start;
 519         }
 520
 521         char buf[16];
 522         sprintf(buf, "%d", state_fd);
 523
 524         for ( ;; ) {
 525                 execlp(argv0_canon, argv0_canon, config_filename_canon, "--state", buf, NULL);
 526                 open_logs(config.log_destinations);
 527                 log_perror("execlp");
 528                 log(ERROR, "re-exec of %s failed. Waiting 0.2 seconds and trying again...", argv0_canon);
 529                 shut_down_logging();
 530                 usleep(200000);
 531         }
 532 }