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

   1 #include <assert.h>
   2 #include <errno.h>
   3 #include <getopt.h>
   4 #include <signal.h>
   5 #include <stddef.h>
   6 #include <stdio.h>
   7 #include <stdlib.h>
   8 #include <string.h>
   9 #include <sys/time.h>
  10 #include <sys/wait.h>
  11 #include <unistd.h>
  12 #include <map>
  13 #include <set>
  14 #include <string>
  15 #include <utility>
  16 #include <vector>
  17
  18 #include "acceptor.h"
  19 #include "config.h"
  20 #include "input.h"
  21 #include "log.h"
  22 #include "markpool.h"
  23 #include "serverpool.h"
  24 #include "state.pb.h"
  25 #include "stats.h"
  26 #include "util.h"
  27 #include "version.h"
  28
  29 using namespace std;
  30
  31 ServerPool *servers = NULL;
  32 volatile bool hupped = false;
  33
  34 void hup(int ignored)
  35 {
  36         hupped = true;
  37 }
  38
  39 CubemapStateProto collect_state(const timeval &serialize_start,
  40                                 const vector<Acceptor *> acceptors,
  41                                 const vector<Input *> inputs,
  42                                 ServerPool *servers)
  43 {
  44         CubemapStateProto state = servers->serialize();  // Fills streams() and clients().
  45         state.set_serialize_start_sec(serialize_start.tv_sec);
  46         state.set_serialize_start_usec(serialize_start.tv_usec);
  47
  48         for (size_t i = 0; i < acceptors.size(); ++i) {
  49                 state.add_acceptors()->MergeFrom(acceptors[i]->serialize());
  50         }
  51
  52         for (size_t i = 0; i < inputs.size(); ++i) {
  53                 state.add_inputs()->MergeFrom(inputs[i]->serialize());
  54         }
  55
  56         return state;
  57 }
  58
  59 // Find all port statements in the configuration file, and create acceptors for htem.
  60 vector<Acceptor *> create_acceptors(
  61         const Config &config,
  62         map<int, Acceptor *> *deserialized_acceptors)
  63 {
  64         vector<Acceptor *> acceptors;
  65         for (unsigned i = 0; i < config.acceptors.size(); ++i) {
  66                 const AcceptorConfig &acceptor_config = config.acceptors[i];
  67                 Acceptor *acceptor = NULL;
  68                 map<int, Acceptor *>::iterator deserialized_acceptor_it =
  69                         deserialized_acceptors->find(acceptor_config.port);
  70                 if (deserialized_acceptor_it != deserialized_acceptors->end()) {
  71                         acceptor = deserialized_acceptor_it->second;
  72                         deserialized_acceptors->erase(deserialized_acceptor_it);
  73                 } else {
  74                         int server_sock = create_server_socket(acceptor_config.port, TCP_SOCKET);
  75                         acceptor = new Acceptor(server_sock, acceptor_config.port);
  76                 }
  77                 acceptor->run();
  78                 acceptors.push_back(acceptor);
  79         }
  80
  81         // Close all acceptors that are no longer in the configuration file.
  82         for (map<int, Acceptor *>::iterator acceptor_it = deserialized_acceptors->begin();
  83              acceptor_it != deserialized_acceptors->end();
  84              ++acceptor_it) {
  85                 acceptor_it->second->close_socket();
  86                 delete acceptor_it->second;
  87         }
  88
  89         return acceptors;
  90 }
  91
  92 // Find all streams in the configuration file, and create inputs for them.
  93 vector<Input *> create_inputs(const Config &config,
  94                               map<string, Input *> *deserialized_inputs)
  95 {
  96         vector<Input *> inputs;
  97         for (unsigned i = 0; i < config.streams.size(); ++i) {
  98                 const StreamConfig &stream_config = config.streams[i];
  99                 if (stream_config.src.empty()) {
 100                         continue;
 101                 }
 102
 103                 string stream_id = stream_config.stream_id;
 104                 string src = stream_config.src;
 105
 106                 Input *input = NULL;
 107                 map<string, Input *>::iterator deserialized_input_it =
 108                         deserialized_inputs->find(stream_id);
 109                 if (deserialized_input_it != deserialized_inputs->end()) {
 110                         input = deserialized_input_it->second;
 111                         if (input->get_url() != src) {
 112                                 log(INFO, "Stream '%s' has changed URL from '%s' to '%s', restarting input.",
 113                                         stream_id.c_str(), input->get_url().c_str(), src.c_str());
 114                                 input->close_socket();
 115                                 delete input;
 116                                 input = NULL;
 117                         }
 118                         deserialized_inputs->erase(deserialized_input_it);
 119                 }
 120                 if (input == NULL) {
 121                         input = create_input(stream_id, src);
 122                         if (input == NULL) {
 123                                 log(ERROR, "did not understand URL '%s', clients will not get any data.",
 124                                         src.c_str());
 125                                 continue;
 126                         }
 127                 }
 128                 input->run();
 129                 inputs.push_back(input);
 130         }
 131         return inputs;
 132 }
 133
 134 void create_streams(const Config &config,
 135                     const set<string> &deserialized_stream_ids,
 136                     map<string, Input *> *deserialized_inputs)
 137 {
 138         vector<MarkPool *> mark_pools;  // FIXME: leak
 139         for (unsigned i = 0; i < config.mark_pools.size(); ++i) {
 140                 const MarkPoolConfig &mp_config = config.mark_pools[i];
 141                 mark_pools.push_back(new MarkPool(mp_config.from, mp_config.to));
 142         }
 143
 144         set<string> expecting_stream_ids = deserialized_stream_ids;
 145         for (unsigned i = 0; i < config.streams.size(); ++i) {
 146                 const StreamConfig &stream_config = config.streams[i];
 147                 if (deserialized_stream_ids.count(stream_config.stream_id) == 0) {
 148                         servers->add_stream(stream_config.stream_id, stream_config.backlog_size);
 149                 } else {
 150                         servers->set_backlog_size(stream_config.stream_id, stream_config.backlog_size);
 151                 }
 152                 expecting_stream_ids.erase(stream_config.stream_id);
 153
 154                 if (stream_config.mark_pool != -1) {
 155                         servers->set_mark_pool(stream_config.stream_id,
 156                                                mark_pools[stream_config.mark_pool]);
 157                 }
 158         }
 159
 160         // Warn about any servers we've lost.
 161         // TODO: Make an option (delete=yes?) to actually shut down streams.
 162         for (set<string>::const_iterator stream_it = expecting_stream_ids.begin();
 163              stream_it != expecting_stream_ids.end();
 164              ++stream_it) {
 165                 string stream_id = *stream_it;
 166                 log(WARNING, "stream '%s' disappeared from the configuration file. "
 167                              "It will not be deleted, but clients will not get any new inputs.",
 168                              stream_id.c_str());
 169                 if (deserialized_inputs->count(stream_id) != 0) {
 170                         delete (*deserialized_inputs)[stream_id];
 171                         deserialized_inputs->erase(stream_id);
 172                 }
 173         }
 174 }
 175
 176 void open_logs(const vector<LogConfig> &log_destinations)
 177 {
 178         for (size_t i = 0; i < log_destinations.size(); ++i) {
 179                 if (log_destinations[i].type == LogConfig::LOG_TYPE_FILE) {
 180                         add_log_destination_file(log_destinations[i].filename);
 181                 } else if (log_destinations[i].type == LogConfig::LOG_TYPE_CONSOLE) {
 182                         add_log_destination_console();
 183                 } else if (log_destinations[i].type == LogConfig::LOG_TYPE_SYSLOG) {
 184                         add_log_destination_syslog();
 185                 } else {
 186                         assert(false);
 187                 }
 188         }
 189         start_logging();
 190 }
 191
 192 bool dry_run_config(const std::string &argv0, const std::string &config_filename)
 193 {
 194         char *argv0_copy = strdup(argv0.c_str());
 195         char *config_filename_copy = strdup(config_filename.c_str());
 196
 197         pid_t pid = fork();
 198         switch (pid) {
 199         case -1:
 200                 log_perror("fork()");
 201                 free(argv0_copy);
 202                 free(config_filename_copy);
 203                 return false;
 204         case 0:
 205                 // Child.
 206                 execlp(argv0_copy, argv0_copy, "--test-config", config_filename_copy, NULL);
 207                 log_perror(argv0_copy);
 208                 _exit(1);
 209         default:
 210                 // Parent.
 211                 break;
 212         }
 213
 214         free(argv0_copy);
 215         free(config_filename_copy);
 216
 217         int status;
 218         pid_t err;
 219         do {
 220                 err = waitpid(pid, &status, 0);
 221         } while (err == -1 && errno == EINTR);
 222
 223         if (err == -1) {
 224                 log_perror("waitpid()");
 225                 return false;
 226         }
 227
 228         return (WIFEXITED(status) && WEXITSTATUS(status) == 0);
 229 }
 230
 231 int main(int argc, char **argv)
 232 {
 233         signal(SIGHUP, hup);
 234         signal(SIGPIPE, SIG_IGN);
 235
 236         // Parse options.
 237         int state_fd = -1;
 238         bool test_config = false;
 239         for ( ;; ) {
 240                 static const option long_options[] = {
 241                         { "state", required_argument, 0, 's' },
 242                         { "test-config", no_argument, 0, 't' },
 243                 };
 244                 int option_index = 0;
 245                 int c = getopt_long (argc, argv, "s:t", long_options, &option_index);
 246
 247                 if (c == -1) {
 248                         break;
 249                 }
 250                 switch (c) {
 251                 case 's':
 252                         state_fd = atoi(optarg);
 253                         break;
 254                 case 't':
 255                         test_config = true;
 256                         break;
 257                 default:
 258                         assert(false);
 259                 }
 260         }
 261
 262         string config_filename = "cubemap.config";
 263         if (optind < argc) {
 264                 config_filename = argv[optind++];
 265         }
 266
 267         Config config;
 268         if (!parse_config(config_filename, &config)) {
 269                 exit(1);
 270         }
 271         if (test_config) {
 272                 exit(0);
 273         }
 274
 275 start:
 276         // Open logs as soon as possible.
 277         open_logs(config.log_destinations);
 278
 279         log(INFO, "Cubemap " SERVER_VERSION " starting.");
 280         servers = new ServerPool(config.num_servers);
 281
 282         CubemapStateProto loaded_state;
 283         struct timeval serialize_start;
 284         set<string> deserialized_stream_ids;
 285         map<string, Input *> deserialized_inputs;
 286         map<int, Acceptor *> deserialized_acceptors;
 287         if (state_fd != -1) {
 288                 log(INFO, "Deserializing state from previous process...");
 289                 string serialized;
 290                 if (!read_tempfile(state_fd, &serialized)) {
 291                         exit(1);
 292                 }
 293                 if (!loaded_state.ParseFromString(serialized)) {
 294                         log(ERROR, "Failed deserialization of state.");
 295                         exit(1);
 296                 }
 297
 298                 serialize_start.tv_sec = loaded_state.serialize_start_sec();
 299                 serialize_start.tv_usec = loaded_state.serialize_start_usec();
 300
 301                 // Deserialize the streams.
 302                 for (int i = 0; i < loaded_state.streams_size(); ++i) {
 303                         servers->add_stream_from_serialized(loaded_state.streams(i));
 304                         deserialized_stream_ids.insert(loaded_state.streams(i).stream_id());
 305                 }
 306
 307                 // Deserialize the inputs. Note that we don't actually add them to any state yet.
 308                 for (int i = 0; i < loaded_state.inputs_size(); ++i) {
 309                         deserialized_inputs.insert(make_pair(
 310                                 loaded_state.inputs(i).stream_id(),
 311                                 create_input(loaded_state.inputs(i))));
 312                 }
 313
 314                 // Deserialize the acceptors.
 315                 for (int i = 0; i < loaded_state.acceptors_size(); ++i) {
 316                         deserialized_acceptors.insert(make_pair(
 317                                 loaded_state.acceptors(i).port(),
 318                                 new Acceptor(loaded_state.acceptors(i))));
 319                 }
 320
 321                 log(INFO, "Deserialization done.");
 322         }
 323
 324         // Find all streams in the configuration file, and create them.
 325         create_streams(config, deserialized_stream_ids, &deserialized_inputs);
 326
 327         vector<Acceptor *> acceptors = create_acceptors(config, &deserialized_acceptors);
 328         vector<Input *> inputs = create_inputs(config, &deserialized_inputs);
 329
 330         // All deserialized inputs should now have been taken care of, one way or the other.
 331         assert(deserialized_inputs.empty());
 332
 333         // Put back the existing clients. It doesn't matter which server we
 334         // allocate them to, so just do round-robin. However, we need to add
 335         // them after the mark pools have been set up.
 336         for (int i = 0; i < loaded_state.clients_size(); ++i) {
 337                 servers->add_client_from_serialized(loaded_state.clients(i));
 338         }
 339
 340         servers->run();
 341
 342         // Start writing statistics.
 343         StatsThread *stats_thread = NULL;
 344         if (!config.stats_file.empty()) {
 345                 stats_thread = new StatsThread(config.stats_file, config.stats_interval);
 346                 stats_thread->run();
 347         }
 348
 349         struct timeval server_start;
 350         gettimeofday(&server_start, NULL);
 351         if (state_fd != -1) {
 352                 // Measure time from we started deserializing (below) to now, when basically everything
 353                 // is up and running. This is, in other words, a conservative estimate of how long our
 354                 // “glitch” period was, not counting of course reconnects if the configuration changed.
 355                 double glitch_time = server_start.tv_sec - serialize_start.tv_sec +
 356                         1e-6 * (server_start.tv_usec - serialize_start.tv_usec);
 357                 log(INFO, "Re-exec happened in approx. %.0f ms.", glitch_time * 1000.0);
 358         }
 359
 360         while (!hupped) {
 361                 usleep(100000);
 362         }
 363
 364         // OK, we've been HUPed. Time to shut down everything, serialize, and re-exec.
 365         gettimeofday(&serialize_start, NULL);
 366
 367         if (stats_thread != NULL) {
 368                 stats_thread->stop();
 369         }
 370         for (size_t i = 0; i < acceptors.size(); ++i) {
 371                 acceptors[i]->stop();
 372         }
 373         for (size_t i = 0; i < inputs.size(); ++i) {
 374                 inputs[i]->stop();
 375         }
 376         servers->stop();
 377
 378         log(INFO, "Serializing state and re-execing...");
 379         CubemapStateProto state = collect_state(
 380                 serialize_start, acceptors, inputs, servers);
 381         string serialized;
 382         state.SerializeToString(&serialized);
 383         state_fd = make_tempfile(serialized);
 384         if (state_fd == -1) {
 385                 exit(1);
 386         }
 387         delete servers;
 388         shut_down_logging();
 389
 390         if (!dry_run_config(argv[0], config_filename)) {
 391                 open_logs(config.log_destinations);
 392                 log(ERROR, "%s --test-config failed. Restarting old version instead of new.", argv[0]);
 393                 hupped = false;
 394                 shut_down_logging();
 395                 goto start;
 396         }
 397
 398
 399         char buf[16];
 400         sprintf(buf, "%d", state_fd);
 401
 402         for ( ;; ) {
 403                 execlp(argv[0], argv[0], config_filename.c_str(), "--state", buf, NULL);
 404                 open_logs(config.log_destinations);
 405                 log_perror("execlp");
 406                 log(ERROR, "re-exec of %s failed. Waiting 0.2 seconds and trying again...", argv[0]);
 407                 shut_down_logging();
 408                 usleep(200000);
 409         }
 410 }