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
 209                 string src = udpstream_config.src;
 210                 if (!src.empty()) {
 211                         multimap<string, InputWithRefcount>::iterator input_it = inputs->find(src);
 212                         assert(input_it != inputs->end());
 213                         input_it->second.input->add_destination(stream_index);
 214                         ++input_it->second.refcount;
 215                 }
 216         }
 217 }
 218
 219 void open_logs(const vector<LogConfig> &log_destinations)
 220 {
 221         for (size_t i = 0; i < log_destinations.size(); ++i) {
 222                 if (log_destinations[i].type == LogConfig::LOG_TYPE_FILE) {
 223                         add_log_destination_file(log_destinations[i].filename);
 224                 } else if (log_destinations[i].type == LogConfig::LOG_TYPE_CONSOLE) {
 225                         add_log_destination_console();
 226                 } else if (log_destinations[i].type == LogConfig::LOG_TYPE_SYSLOG) {
 227                         add_log_destination_syslog();
 228                 } else {
 229                         assert(false);
 230                 }
 231         }
 232         start_logging();
 233 }
 234
 235 bool dry_run_config(const std::string &argv0, const std::string &config_filename)
 236 {
 237         char *argv0_copy = strdup(argv0.c_str());
 238         char *config_filename_copy = strdup(config_filename.c_str());
 239
 240         pid_t pid = fork();
 241         switch (pid) {
 242         case -1:
 243                 log_perror("fork()");
 244                 free(argv0_copy);
 245                 free(config_filename_copy);
 246                 return false;
 247         case 0:
 248                 // Child.
 249                 execlp(argv0_copy, argv0_copy, "--test-config", config_filename_copy, NULL);
 250                 log_perror(argv0_copy);
 251                 _exit(1);
 252         default:
 253                 // Parent.
 254                 break;
 255         }
 256
 257         free(argv0_copy);
 258         free(config_filename_copy);
 259
 260         int status;
 261         pid_t err;
 262         do {
 263                 err = waitpid(pid, &status, 0);
 264         } while (err == -1 && errno == EINTR);
 265
 266         if (err == -1) {
 267                 log_perror("waitpid()");
 268                 return false;
 269         }
 270
 271         return (WIFEXITED(status) && WEXITSTATUS(status) == 0);
 272 }
 273
 274 void find_deleted_streams(const Config &config, set<string> *deleted_urls)
 275 {
 276         for (unsigned i = 0; i < config.streams.size(); ++i) {
 277                 const StreamConfig &stream_config = config.streams[i];
 278                 if (stream_config.src == "delete") {
 279                         log(INFO, "Deleting stream '%s'.", stream_config.url.c_str());
 280                         deleted_urls->insert(stream_config.url);
 281                 }
 282         }
 283 }
 284
 285 int main(int argc, char **argv)
 286 {
 287         signal(SIGHUP, hup);
 288         signal(SIGINT, hup);
 289         signal(SIGUSR1, do_nothing);  // Used in internal signalling.
 290         signal(SIGPIPE, SIG_IGN);
 291
 292         // Parse options.
 293         int state_fd = -1;
 294         bool test_config = false;
 295         for ( ;; ) {
 296                 static const option long_options[] = {
 297                         { "state", required_argument, 0, 's' },
 298                         { "test-config", no_argument, 0, 't' },
 299                         { 0, 0, 0, 0 }
 300                 };
 301                 int option_index = 0;
 302                 int c = getopt_long(argc, argv, "s:t", long_options, &option_index);
 303
 304                 if (c == -1) {
 305                         break;
 306                 }
 307                 switch (c) {
 308                 case 's':
 309                         state_fd = atoi(optarg);
 310                         break;
 311                 case 't':
 312                         test_config = true;
 313                         break;
 314                 default:
 315                         fprintf(stderr, "Unknown option '%s'\n", argv[option_index]);
 316                         exit(1);
 317                 }
 318         }
 319
 320         string config_filename = "cubemap.config";
 321         if (optind < argc) {
 322                 config_filename = argv[optind++];
 323         }
 324
 325         // Canonicalize argv[0] and config_filename.
 326         char argv0_canon[PATH_MAX];
 327         char config_filename_canon[PATH_MAX];
 328
 329         if (realpath("/proc/self/exe", argv0_canon) == NULL) {
 330                 log_perror(argv[0]);
 331                 exit(1);
 332         }
 333         if (realpath(config_filename.c_str(), config_filename_canon) == NULL) {
 334                 log_perror(config_filename.c_str());
 335                 exit(1);
 336         }
 337
 338         // Now parse the configuration file.
 339         Config config;
 340         if (!parse_config(config_filename_canon, &config)) {
 341                 exit(1);
 342         }
 343         if (test_config) {
 344                 exit(0);
 345         }
 346
 347         // Ideally we'd like to daemonize only when we've started up all threads etc.,
 348         // but daemon() forks, which is not good in multithreaded software, so we'll
 349         // have to do it here.
 350         if (config.daemonize) {
 351                 if (daemon(0, 0) == -1) {
 352                         log_perror("daemon");
 353                         exit(1);
 354                 }
 355         }
 356
 357 start:
 358         // Open logs as soon as possible.
 359         open_logs(config.log_destinations);
 360
 361         log(INFO, "Cubemap " SERVER_VERSION " starting.");
 362         if (config.access_log_file.empty()) {
 363                 // Create a dummy logger.
 364                 access_log = new AccessLogThread();
 365         } else {
 366                 access_log = new AccessLogThread(config.access_log_file);
 367         }
 368         access_log->run();
 369
 370         servers = new ServerPool(config.num_servers);
 371
 372         // Find all the streams that are to be deleted.
 373         set<string> deleted_urls;
 374         find_deleted_streams(config, &deleted_urls);
 375
 376         CubemapStateProto loaded_state;
 377         struct timeval serialize_start;
 378         set<string> deserialized_urls;
 379         map<sockaddr_in6, Acceptor *, Sockaddr6Compare> deserialized_acceptors;
 380         multimap<string, InputWithRefcount> inputs;  // multimap due to older versions without deduplication.
 381         if (state_fd != -1) {
 382                 log(INFO, "Deserializing state from previous process...");
 383                 string serialized;
 384                 if (!read_tempfile_and_close(state_fd, &serialized)) {
 385                         exit(1);
 386                 }
 387                 if (!loaded_state.ParseFromString(serialized)) {
 388                         log(ERROR, "Failed deserialization of state.");
 389                         exit(1);
 390                 }
 391
 392                 serialize_start.tv_sec = loaded_state.serialize_start_sec();
 393                 serialize_start.tv_usec = loaded_state.serialize_start_usec();
 394
 395                 // Deserialize the streams.
 396                 map<string, string> stream_headers_for_url;  // See below.
 397                 for (int i = 0; i < loaded_state.streams_size(); ++i) {
 398                         const StreamProto &stream = loaded_state.streams(i);
 399
 400                         if (deleted_urls.count(stream.url()) != 0) {
 401                                 // Delete the stream backlogs.
 402                                 for (int j = 0; j < stream.data_fds_size(); ++j) {
 403                                         safe_close(stream.data_fds(j));
 404                                 }
 405                         } else {
 406                                 vector<int> data_fds;
 407                                 for (int j = 0; j < stream.data_fds_size(); ++j) {
 408                                         data_fds.push_back(stream.data_fds(j));
 409                                 }
 410
 411                                 servers->add_stream_from_serialized(stream, data_fds);
 412                                 deserialized_urls.insert(stream.url());
 413
 414                                 stream_headers_for_url.insert(make_pair(stream.url(), stream.stream_header()));
 415                         }
 416                 }
 417
 418                 // Deserialize the inputs. Note that we don't actually add them to any stream yet.
 419                 for (int i = 0; i < loaded_state.inputs_size(); ++i) {
 420                         InputProto serialized_input = loaded_state.inputs(i);
 421
 422                         InputWithRefcount iwr;
 423                         iwr.input = create_input(serialized_input);
 424                         iwr.refcount = 0;
 425                         inputs.insert(make_pair(serialized_input.url(), iwr));
 426                 }
 427
 428                 // Deserialize the acceptors.
 429                 for (int i = 0; i < loaded_state.acceptors_size(); ++i) {
 430                         sockaddr_in6 sin6 = ExtractAddressFromAcceptorProto(loaded_state.acceptors(i));
 431                         deserialized_acceptors.insert(make_pair(
 432                                 sin6,
 433                                 new Acceptor(loaded_state.acceptors(i))));
 434                 }
 435
 436                 log(INFO, "Deserialization done.");
 437         }
 438
 439         // Add any new inputs coming from the config.
 440         create_config_inputs(config, &inputs);
 441
 442         // Find all streams in the configuration file, create them, and connect to the inputs.
 443         create_streams(config, deserialized_urls, &inputs);
 444         vector<Acceptor *> acceptors = create_acceptors(config, &deserialized_acceptors);
 445
 446         // Put back the existing clients. It doesn't matter which server we
 447         // allocate them to, so just do round-robin.
 448         for (int i = 0; i < loaded_state.clients_size(); ++i) {
 449                 if (deleted_urls.count(loaded_state.clients(i).url()) != 0) {
 450                         safe_close(loaded_state.clients(i).sock());
 451                 } else {
 452                         servers->add_client_from_serialized(loaded_state.clients(i));
 453                 }
 454         }
 455
 456         servers->run();
 457
 458         // Now delete all inputs that are longer in use, and start the others.
 459         for (multimap<string, InputWithRefcount>::iterator input_it = inputs.begin();
 460              input_it != inputs.end(); ) {
 461                 if (input_it->second.refcount == 0) {
 462                         log(WARNING, "Input '%s' no longer in use, closing.",
 463                             input_it->first.c_str());
 464                         input_it->second.input->close_socket();
 465                         delete input_it->second.input;
 466                         inputs.erase(input_it++);
 467                 } else {
 468                         input_it->second.input->run();
 469                         ++input_it;
 470                 }
 471         }
 472
 473         // Start writing statistics.
 474         StatsThread *stats_thread = NULL;
 475         if (!config.stats_file.empty()) {
 476                 stats_thread = new StatsThread(config.stats_file, config.stats_interval);
 477                 stats_thread->run();
 478         }
 479
 480         InputStatsThread *input_stats_thread = NULL;
 481         if (!config.input_stats_file.empty()) {
 482                 vector<Input*> inputs_no_refcount;
 483                 for (multimap<string, InputWithRefcount>::iterator input_it = inputs.begin();
 484                      input_it != inputs.end(); ++input_it) {
 485                         inputs_no_refcount.push_back(input_it->second.input);
 486                 }
 487
 488                 input_stats_thread = new InputStatsThread(config.input_stats_file, config.input_stats_interval, inputs_no_refcount);
 489                 input_stats_thread->run();
 490         }
 491
 492         struct timeval server_start;
 493         gettimeofday(&server_start, NULL);
 494         if (state_fd != -1) {
 495                 // Measure time from we started deserializing (below) to now, when basically everything
 496                 // is up and running. This is, in other words, a conservative estimate of how long our
 497                 // “glitch” period was, not counting of course reconnects if the configuration changed.
 498                 double glitch_time = server_start.tv_sec - serialize_start.tv_sec +
 499                         1e-6 * (server_start.tv_usec - serialize_start.tv_usec);
 500                 log(INFO, "Re-exec happened in approx. %.0f ms.", glitch_time * 1000.0);
 501         }
 502
 503         while (!hupped) {
 504                 usleep(100000);
 505         }
 506
 507         // OK, we've been HUPed. Time to shut down everything, serialize, and re-exec.
 508         gettimeofday(&serialize_start, NULL);
 509
 510         if (input_stats_thread != NULL) {
 511                 input_stats_thread->stop();
 512                 delete input_stats_thread;
 513         }
 514         if (stats_thread != NULL) {
 515                 stats_thread->stop();
 516                 delete stats_thread;
 517         }
 518         for (size_t i = 0; i < acceptors.size(); ++i) {
 519                 acceptors[i]->stop();
 520         }
 521         for (multimap<string, InputWithRefcount>::iterator input_it = inputs.begin();
 522              input_it != inputs.end();
 523              ++input_it) {
 524                 input_it->second.input->stop();
 525         }
 526         servers->stop();
 527
 528         CubemapStateProto state;
 529         if (stopped) {
 530                 log(INFO, "Shutting down.");
 531         } else {
 532                 log(INFO, "Serializing state and re-execing...");
 533                 state = collect_state(
 534                         serialize_start, acceptors, inputs, servers);
 535                 string serialized;
 536                 state.SerializeToString(&serialized);
 537                 state_fd = make_tempfile(serialized);
 538                 if (state_fd == -1) {
 539                         exit(1);
 540                 }
 541         }
 542         delete servers;
 543
 544         access_log->stop();
 545         delete access_log;
 546         shut_down_logging();
 547
 548         if (stopped) {
 549                 exit(0);
 550         }
 551
 552         // OK, so the signal was SIGHUP. Check that the new config is okay, then exec the new binary.
 553         if (!dry_run_config(argv0_canon, config_filename_canon)) {
 554                 open_logs(config.log_destinations);
 555                 log(ERROR, "%s --test-config failed. Restarting old version instead of new.", argv[0]);
 556                 hupped = false;
 557                 shut_down_logging();
 558                 goto start;
 559         }
 560
 561         char buf[16];
 562         sprintf(buf, "%d", state_fd);
 563
 564         for ( ;; ) {
 565                 execlp(argv0_canon, argv0_canon, config_filename_canon, "--state", buf, NULL);
 566                 open_logs(config.log_destinations);
 567                 log_perror("execlp");
 568                 log(ERROR, "re-exec of %s failed. Waiting 0.2 seconds and trying again...", argv0_canon);
 569                 shut_down_logging();
 570                 usleep(200000);
 571         }
 572 }