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

   1 #include <stdio.h>
   2 #include <string.h>
   3 #include <stdint.h>
   4 #include <assert.h>
   5 #include <arpa/inet.h>
   6 #include <sys/socket.h>
   7 #include <pthread.h>
   8 #include <sys/types.h>
   9 #include <sys/ioctl.h>
  10 #include <sys/epoll.h>
  11 #include <time.h>
  12 #include <signal.h>
  13 #include <errno.h>
  14 #include <vector>
  15 #include <string>
  16 #include <map>
  17 #include <algorithm>
  18
  19 #include "markpool.h"
  20 #include "metacube.h"
  21 #include "server.h"
  22 #include "mutexlock.h"
  23 #include "parse.h"
  24 #include "state.pb.h"
  25
  26 using namespace std;
  27
  28 Client::Client(int sock)
  29         : sock(sock),
  30           fwmark(0),
  31           connect_time(time(NULL)),
  32           state(Client::READING_REQUEST),
  33           stream(NULL),
  34           header_or_error_bytes_sent(0),
  35           bytes_sent(0)
  36 {
  37         request.reserve(1024);
  38
  39         // Find the remote address, and convert it to ASCII.
  40         sockaddr_in6 addr;
  41         socklen_t addr_len = sizeof(addr);
  42
  43         if (getpeername(sock, reinterpret_cast<sockaddr *>(&addr), &addr_len) == -1) {
  44                 perror("getpeername");
  45                 remote_addr = "";
  46         } else {
  47                 char buf[INET6_ADDRSTRLEN];
  48                 if (inet_ntop(addr.sin6_family, &addr.sin6_addr, buf, sizeof(buf)) == NULL) {
  49                         perror("inet_ntop");
  50                         remote_addr = "";
  51                 } else {
  52                         remote_addr = buf;
  53                 }
  54         }
  55 }
  56
  57 Client::Client(const ClientProto &serialized, Stream *stream)
  58         : sock(serialized.sock()),
  59           remote_addr(serialized.remote_addr()),
  60           connect_time(serialized.connect_time()),
  61           state(State(serialized.state())),
  62           request(serialized.request()),
  63           stream_id(serialized.stream_id()),
  64           stream(stream),
  65           header_or_error(serialized.header_or_error()),
  66           header_or_error_bytes_sent(serialized.header_or_error_bytes_sent()),
  67           bytes_sent(serialized.bytes_sent())
  68 {
  69         if (stream->mark_pool != NULL) {
  70                 fwmark = stream->mark_pool->get_mark();
  71         } else {
  72                 fwmark = 0;  // No mark.
  73         }
  74         if (setsockopt(sock, SOL_SOCKET, SO_MARK, &fwmark, sizeof(fwmark)) == -1) {
  75                 if (fwmark != 0) {
  76                         perror("setsockopt(SO_MARK)");
  77                 }
  78         }
  79 }
  80
  81 ClientProto Client::serialize() const
  82 {
  83         ClientProto serialized;
  84         serialized.set_sock(sock);
  85         serialized.set_remote_addr(remote_addr);
  86         serialized.set_connect_time(connect_time);
  87         serialized.set_state(state);
  88         serialized.set_request(request);
  89         serialized.set_stream_id(stream_id);
  90         serialized.set_header_or_error(header_or_error);
  91         serialized.set_header_or_error_bytes_sent(serialized.header_or_error_bytes_sent());
  92         serialized.set_bytes_sent(bytes_sent);
  93         return serialized;
  94 }
  95
  96 ClientStats Client::get_stats() const
  97 {
  98         ClientStats stats;
  99         stats.stream_id = stream_id;
 100         stats.remote_addr = remote_addr;
 101         stats.connect_time = connect_time;
 102         stats.bytes_sent = bytes_sent;
 103         return stats;
 104 }
 105
 106 Stream::Stream(const string &stream_id)
 107         : stream_id(stream_id),
 108           data(new char[BACKLOG_SIZE]),
 109           data_size(0),
 110           mark_pool(NULL)
 111 {
 112         memset(data, 0, BACKLOG_SIZE);
 113 }
 114
 115 Stream::~Stream()
 116 {
 117         delete[] data;
 118 }
 119
 120 Stream::Stream(const StreamProto &serialized)
 121         : stream_id(serialized.stream_id()),
 122           header(serialized.header()),
 123           data(new char[BACKLOG_SIZE]),
 124           data_size(serialized.data_size()),
 125           mark_pool(NULL)
 126 {
 127         assert(serialized.data().size() == BACKLOG_SIZE);
 128         memcpy(data, serialized.data().data(), BACKLOG_SIZE);
 129 }
 130
 131 StreamProto Stream::serialize() const
 132 {
 133         StreamProto serialized;
 134         serialized.set_header(header);
 135         serialized.set_data(string(data, data + BACKLOG_SIZE));
 136         serialized.set_data_size(data_size);
 137         serialized.set_stream_id(stream_id);
 138         return serialized;
 139 }
 140
 141 void Stream::put_client_to_sleep(Client *client)
 142 {
 143         sleeping_clients.push_back(client);
 144 }
 145
 146 void Stream::wake_up_all_clients()
 147 {
 148         if (to_process.empty()) {
 149                 swap(sleeping_clients, to_process);
 150         } else {
 151                 to_process.insert(to_process.end(), sleeping_clients.begin(), sleeping_clients.end());
 152                 sleeping_clients.clear();
 153         }
 154 }
 155
 156 Server::Server()
 157 {
 158         pthread_mutex_init(&mutex, NULL);
 159         pthread_mutex_init(&queued_data_mutex, NULL);
 160
 161         epoll_fd = epoll_create(1024);  // Size argument is ignored.
 162         if (epoll_fd == -1) {
 163                 perror("epoll_fd");
 164                 exit(1);
 165         }
 166 }
 167
 168 Server::~Server()
 169 {
 170         int ret;
 171         do {
 172                 ret = close(epoll_fd);
 173         } while (ret == -1 && errno == EINTR);
 174
 175         if (ret == -1) {
 176                 perror("close(epoll_fd)");
 177         }
 178 }
 179
 180 void Server::run()
 181 {
 182         should_stop = false;
 183
 184         // Joinable is already the default, but it's good to be certain.
 185         pthread_attr_t attr;
 186         pthread_attr_init(&attr);
 187         pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE);
 188         pthread_create(&worker_thread, &attr, Server::do_work_thunk, this);
 189 }
 190
 191 void Server::stop()
 192 {
 193         {
 194                 MutexLock lock(&mutex);
 195                 should_stop = true;
 196         }
 197
 198         pthread_kill(worker_thread, SIGHUP);
 199         if (pthread_join(worker_thread, NULL) == -1) {
 200                 perror("pthread_join");
 201                 exit(1);
 202         }
 203 }
 204
 205 vector<ClientStats> Server::get_client_stats() const
 206 {
 207         vector<ClientStats> ret;
 208
 209         MutexLock lock(&mutex);
 210         for (map<int, Client>::const_iterator client_it = clients.begin();
 211              client_it != clients.end();
 212              ++client_it) {
 213                 ret.push_back(client_it->second.get_stats());
 214         }
 215         return ret;
 216 }
 217
 218 void *Server::do_work_thunk(void *arg)
 219 {
 220         Server *server = static_cast<Server *>(arg);
 221         server->do_work();
 222         return NULL;
 223 }
 224
 225 void Server::do_work()
 226 {
 227         for ( ;; ) {
 228                 int nfds = epoll_wait(epoll_fd, events, EPOLL_MAX_EVENTS, EPOLL_TIMEOUT_MS);
 229                 if (nfds == -1 && errno == EINTR) {
 230                         if (should_stop) {
 231                                 return;
 232                         }
 233                         continue;
 234                 }
 235                 if (nfds == -1) {
 236                         perror("epoll_wait");
 237                         exit(1);
 238                 }
 239
 240                 MutexLock lock(&mutex);  // We release the mutex between iterations.
 241
 242                 process_queued_data();
 243
 244                 for (int i = 0; i < nfds; ++i) {
 245                         int fd = events[i].data.fd;
 246                         assert(clients.count(fd) != 0);
 247                         Client *client = &clients[fd];
 248
 249                         if (events[i].events & (EPOLLERR | EPOLLRDHUP | EPOLLHUP)) {
 250                                 close_client(client);
 251                                 continue;
 252                         }
 253
 254                         process_client(client);
 255                 }
 256
 257                 for (map<string, Stream *>::iterator stream_it = streams.begin();
 258                      stream_it != streams.end();
 259                      ++stream_it) {
 260                         vector<Client *> to_process;
 261                         swap(stream_it->second->to_process, to_process);
 262                         for (size_t i = 0; i < to_process.size(); ++i) {
 263                                 process_client(to_process[i]);
 264                         }
 265                 }
 266
 267                 if (should_stop) {
 268                         return;
 269                 }
 270         }
 271 }
 272
 273 CubemapStateProto Server::serialize()
 274 {
 275         // We don't serialize anything queued, so empty the queues.
 276         process_queued_data();
 277
 278         CubemapStateProto serialized;
 279         for (map<int, Client>::const_iterator client_it = clients.begin();
 280              client_it != clients.end();
 281              ++client_it) {
 282                 serialized.add_clients()->MergeFrom(client_it->second.serialize());
 283         }
 284         for (map<string, Stream *>::const_iterator stream_it = streams.begin();
 285              stream_it != streams.end();
 286              ++stream_it) {
 287                 serialized.add_streams()->MergeFrom(stream_it->second->serialize());
 288         }
 289         return serialized;
 290 }
 291
 292 void Server::add_client_deferred(int sock)
 293 {
 294         MutexLock lock(&queued_data_mutex);
 295         queued_add_clients.push_back(sock);
 296 }
 297
 298 void Server::add_client(int sock)
 299 {
 300         clients.insert(make_pair(sock, Client(sock)));
 301
 302         // Start listening on data from this socket.
 303         epoll_event ev;
 304         ev.events = EPOLLIN | EPOLLET | EPOLLRDHUP;
 305         ev.data.u64 = 0;  // Keep Valgrind happy.
 306         ev.data.fd = sock;
 307         if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, sock, &ev) == -1) {
 308                 perror("epoll_ctl(EPOLL_CTL_ADD)");
 309                 exit(1);
 310         }
 311
 312         process_client(&clients[sock]);
 313 }
 314
 315 void Server::add_client_from_serialized(const ClientProto &client)
 316 {
 317         MutexLock lock(&mutex);
 318         Stream *stream = find_stream(client.stream_id());
 319         clients.insert(make_pair(client.sock(), Client(client, stream)));
 320         Client *client_ptr = &clients[client.sock()];
 321
 322         // Start listening on data from this socket.
 323         epoll_event ev;
 324         if (client.state() == Client::READING_REQUEST) {
 325                 ev.events = EPOLLIN | EPOLLET | EPOLLRDHUP;
 326         } else {
 327                 // If we don't have more data for this client, we'll be putting it into
 328                 // the sleeping array again soon.
 329                 ev.events = EPOLLOUT | EPOLLET | EPOLLRDHUP;
 330         }
 331         ev.data.u64 = 0;  // Keep Valgrind happy.
 332         ev.data.fd = client.sock();
 333         if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, client.sock(), &ev) == -1) {
 334                 perror("epoll_ctl(EPOLL_CTL_ADD)");
 335                 exit(1);
 336         }
 337
 338         if (client_ptr->state == Client::SENDING_DATA &&
 339             client_ptr->bytes_sent == client_ptr->stream->data_size) {
 340                 client_ptr->stream->put_client_to_sleep(client_ptr);
 341         } else {
 342                 process_client(client_ptr);
 343         }
 344 }
 345
 346 void Server::add_stream(const string &stream_id)
 347 {
 348         MutexLock lock(&mutex);
 349         streams.insert(make_pair(stream_id, new Stream(stream_id)));
 350 }
 351
 352 void Server::add_stream_from_serialized(const StreamProto &stream)
 353 {
 354         MutexLock lock(&mutex);
 355         streams.insert(make_pair(stream.stream_id(), new Stream(stream)));
 356 }
 357
 358 void Server::set_header(const string &stream_id, const string &header)
 359 {
 360         MutexLock lock(&mutex);
 361         find_stream(stream_id)->header = header;
 362
 363         // If there are clients we haven't sent anything to yet, we should give
 364         // them the header, so push back into the SENDING_HEADER state.
 365         for (map<int, Client>::iterator client_it = clients.begin();
 366              client_it != clients.end();
 367              ++client_it) {
 368                 Client *client = &client_it->second;
 369                 if (client->state == Client::SENDING_DATA &&
 370                     client->bytes_sent == 0) {
 371                         construct_header(client);
 372                 }
 373         }
 374 }
 375
 376 void Server::set_mark_pool(const std::string &stream_id, MarkPool *mark_pool)
 377 {
 378         MutexLock lock(&mutex);
 379         assert(clients.empty());
 380         find_stream(stream_id)->mark_pool = mark_pool;
 381 }
 382
 383 void Server::add_data_deferred(const string &stream_id, const char *data, size_t bytes)
 384 {
 385         MutexLock lock(&queued_data_mutex);
 386         queued_data[stream_id].append(string(data, data + bytes));
 387 }
 388
 389 void Server::add_data(const string &stream_id, const char *data, size_t bytes)
 390 {
 391         Stream *stream = find_stream(stream_id);
 392         size_t pos = stream->data_size % BACKLOG_SIZE;
 393         stream->data_size += bytes;
 394
 395         if (pos + bytes > BACKLOG_SIZE) {
 396                 size_t to_copy = BACKLOG_SIZE - pos;
 397                 memcpy(stream->data + pos, data, to_copy);
 398                 data += to_copy;
 399                 bytes -= to_copy;
 400                 pos = 0;
 401         }
 402
 403         memcpy(stream->data + pos, data, bytes);
 404         stream->wake_up_all_clients();
 405 }
 406
 407 // See the .h file for postconditions after this function.
 408 void Server::process_client(Client *client)
 409 {
 410         switch (client->state) {
 411         case Client::READING_REQUEST: {
 412 read_request_again:
 413                 // Try to read more of the request.
 414                 char buf[1024];
 415                 int ret;
 416                 do {
 417                         ret = read(client->sock, buf, sizeof(buf));
 418                 } while (ret == -1 && errno == EINTR);
 419
 420                 if (ret == -1 && errno == EAGAIN) {
 421                         // No more data right now. Nothing to do.
 422                         // This is postcondition #2.
 423                         return;
 424                 }
 425                 if (ret == -1) {
 426                         perror("read");
 427                         close_client(client);
 428                         return;
 429                 }
 430                 if (ret == 0) {
 431                         // OK, the socket is closed.
 432                         close_client(client);
 433                         return;
 434                 }
 435
 436                 RequestParseStatus status = wait_for_double_newline(&client->request, buf, ret);
 437
 438                 switch (status) {
 439                 case RP_OUT_OF_SPACE:
 440                         fprintf(stderr, "WARNING: fd %d sent overlong request!\n", client->sock);
 441                         close_client(client);
 442                         return;
 443                 case RP_NOT_FINISHED_YET:
 444                         // OK, we don't have the entire header yet. Fine; we'll get it later.
 445                         // See if there's more data for us.
 446                         goto read_request_again;
 447                 case RP_EXTRA_DATA:
 448                         fprintf(stderr, "WARNING: fd %d had junk data after request!\n", client->sock);
 449                         close_client(client);
 450                         return;
 451                 case RP_FINISHED:
 452                         break;
 453                 }
 454
 455                 assert(status == RP_FINISHED);
 456
 457                 int error_code = parse_request(client);
 458                 if (error_code == 200) {
 459                         construct_header(client);
 460                 } else {
 461                         construct_error(client, error_code);
 462                 }
 463
 464                 // We've changed states, so fall through.
 465                 assert(client->state == Client::SENDING_ERROR ||
 466                        client->state == Client::SENDING_HEADER);
 467         }
 468         case Client::SENDING_ERROR:
 469         case Client::SENDING_HEADER: {
 470 sending_header_or_error_again:
 471                 int ret;
 472                 do {
 473                         ret = write(client->sock,
 474                                     client->header_or_error.data() + client->header_or_error_bytes_sent,
 475                                     client->header_or_error.size() - client->header_or_error_bytes_sent);
 476                 } while (ret == -1 && errno == EINTR);
 477
 478                 if (ret == -1 && errno == EAGAIN) {
 479                         // We're out of socket space, so now we're at the “low edge” of epoll's
 480                         // edge triggering. epoll will tell us when there is more room, so for now,
 481                         // just return.
 482                         // This is postcondition #4.
 483                         return;
 484                 }
 485
 486                 if (ret == -1) {
 487                         // Error! Postcondition #1.
 488                         perror("write");
 489                         close_client(client);
 490                         return;
 491                 }
 492
 493                 client->header_or_error_bytes_sent += ret;
 494                 assert(client->header_or_error_bytes_sent <= client->header_or_error.size());
 495
 496                 if (client->header_or_error_bytes_sent < client->header_or_error.size()) {
 497                         // We haven't sent all yet. Fine; go another round.
 498                         goto sending_header_or_error_again;
 499                 }
 500
 501                 // We're done sending the header or error! Clear it to release some memory.
 502                 client->header_or_error.clear();
 503
 504                 if (client->state == Client::SENDING_ERROR) {
 505                         // We're done sending the error, so now close.
 506                         // This is postcondition #1.
 507                         close_client(client);
 508                         return;
 509                 }
 510
 511                 // Start sending from the end. In other words, we won't send any of the backlog,
 512                 // but we'll start sending immediately as we get data.
 513                 // This is postcondition #3.
 514                 client->state = Client::SENDING_DATA;
 515                 client->bytes_sent = client->stream->data_size;
 516                 client->stream->put_client_to_sleep(client);
 517                 return;
 518         }
 519         case Client::SENDING_DATA: {
 520                 // See if there's some data we've lost. Ideally, we should drop to a block boundary,
 521                 // but resync will be the mux's problem.
 522                 Stream *stream = client->stream;
 523                 size_t bytes_to_send = stream->data_size - client->bytes_sent;
 524                 if (bytes_to_send == 0) {
 525                         return;
 526                 }
 527                 if (bytes_to_send > BACKLOG_SIZE) {
 528                         fprintf(stderr, "WARNING: fd %d lost %lld bytes, maybe too slow connection\n",
 529                                 client->sock,
 530                                 (long long int)(bytes_to_send - BACKLOG_SIZE));
 531                         client->bytes_sent = stream->data_size - BACKLOG_SIZE;
 532                         bytes_to_send = BACKLOG_SIZE;
 533                 }
 534
 535                 // See if we need to split across the circular buffer.
 536                 ssize_t ret;
 537                 if ((client->bytes_sent % BACKLOG_SIZE) + bytes_to_send > BACKLOG_SIZE) {
 538                         size_t bytes_first_part = BACKLOG_SIZE - (client->bytes_sent % BACKLOG_SIZE);
 539
 540                         iovec iov[2];
 541                         iov[0].iov_base = const_cast<char *>(stream->data + (client->bytes_sent % BACKLOG_SIZE));
 542                         iov[0].iov_len = bytes_first_part;
 543
 544                         iov[1].iov_base = const_cast<char *>(stream->data);
 545                         iov[1].iov_len = bytes_to_send - bytes_first_part;
 546
 547                         do {
 548                                 ret = writev(client->sock, iov, 2);
 549                         } while (ret == -1 && errno == EINTR);
 550                 } else {
 551                         do {
 552                                 ret = write(client->sock,
 553                                             stream->data + (client->bytes_sent % BACKLOG_SIZE),
 554                                             bytes_to_send);
 555                         } while (ret == -1 && errno == EINTR);
 556                 }
 557                 if (ret == -1 && errno == EAGAIN) {
 558                         // We're out of socket space, so return; epoll will wake us up
 559                         // when there is more room.
 560                         // This is postcondition #4.
 561                         return;
 562                 }
 563                 if (ret == -1) {
 564                         // Error, close; postcondition #1.
 565                         perror("write/writev");
 566                         close_client(client);
 567                         return;
 568                 }
 569                 client->bytes_sent += ret;
 570
 571                 if (client->bytes_sent == stream->data_size) {
 572                         // We don't have any more data for this client, so put it to sleep.
 573                         // This is postcondition #3.
 574                         stream->put_client_to_sleep(client);
 575                 } else {
 576                         // XXX: Do we need to go another round here to explicitly
 577                         // get the EAGAIN?
 578                 }
 579                 break;
 580         }
 581         default:
 582                 assert(false);
 583         }
 584 }
 585
 586 int Server::parse_request(Client *client)
 587 {
 588         vector<string> lines = split_lines(client->request);
 589         if (lines.empty()) {
 590                 return 400;  // Bad request (empty).
 591         }
 592
 593         vector<string> request_tokens = split_tokens(lines[0]);
 594         if (request_tokens.size() < 2) {
 595                 return 400;  // Bad request (empty).
 596         }
 597         if (request_tokens[0] != "GET") {
 598                 return 400;  // Should maybe be 405 instead?
 599         }
 600         if (streams.count(request_tokens[1]) == 0) {
 601                 return 404;  // Not found.
 602         }
 603
 604         client->stream_id = request_tokens[1];
 605         client->stream = find_stream(client->stream_id);
 606         if (client->stream->mark_pool != NULL) {
 607                 client->fwmark = client->stream->mark_pool->get_mark();
 608         } else {
 609                 client->fwmark = 0;  // No mark.
 610         }
 611         if (setsockopt(client->sock, SOL_SOCKET, SO_MARK, &client->fwmark, sizeof(client->fwmark)) == -1) {
 612                 if (client->fwmark != 0) {
 613                         perror("setsockopt(SO_MARK)");
 614                 }
 615         }
 616         client->request.clear();
 617
 618         return 200;  // OK!
 619 }
 620
 621 void Server::construct_header(Client *client)
 622 {
 623         client->header_or_error = find_stream(client->stream_id)->header;
 624
 625         // Switch states.
 626         client->state = Client::SENDING_HEADER;
 627
 628         epoll_event ev;
 629         ev.events = EPOLLOUT | EPOLLET | EPOLLRDHUP;
 630         ev.data.u64 = 0;  // Keep Valgrind happy.
 631         ev.data.fd = client->sock;
 632
 633         if (epoll_ctl(epoll_fd, EPOLL_CTL_MOD, client->sock, &ev) == -1) {
 634                 perror("epoll_ctl(EPOLL_CTL_MOD)");
 635                 exit(1);
 636         }
 637 }
 638
 639 void Server::construct_error(Client *client, int error_code)
 640 {
 641         char error[256];
 642         snprintf(error, 256, "HTTP/1.0 %d Error\r\nContent-type: text/plain\r\n\r\nSomething went wrong. Sorry.\r\n",
 643                 error_code);
 644         client->header_or_error = error;
 645
 646         // Switch states.
 647         client->state = Client::SENDING_ERROR;
 648
 649         epoll_event ev;
 650         ev.events = EPOLLOUT | EPOLLET | EPOLLRDHUP;
 651         ev.data.u64 = 0;  // Keep Valgrind happy.
 652         ev.data.fd = client->sock;
 653
 654         if (epoll_ctl(epoll_fd, EPOLL_CTL_MOD, client->sock, &ev) == -1) {
 655                 perror("epoll_ctl(EPOLL_CTL_MOD)");
 656                 exit(1);
 657         }
 658 }
 659
 660 template<class T>
 661 void delete_from(vector<T> *v, T elem)
 662 {
 663         typename vector<T>::iterator new_end = remove(v->begin(), v->end(), elem);
 664         v->erase(new_end, v->end());
 665 }
 666
 667 void Server::close_client(Client *client)
 668 {
 669         if (epoll_ctl(epoll_fd, EPOLL_CTL_DEL, client->sock, NULL) == -1) {
 670                 perror("epoll_ctl(EPOLL_CTL_DEL)");
 671                 exit(1);
 672         }
 673
 674         // This client could be sleeping, so we'll need to fix that. (Argh, O(n).)
 675         if (client->stream != NULL) {
 676                 delete_from(&client->stream->sleeping_clients, client);
 677                 delete_from(&client->stream->to_process, client);
 678                 if (client->stream->mark_pool != NULL) {
 679                         int fwmark = client->fwmark;
 680                         client->stream->mark_pool->release_mark(fwmark);
 681                 }
 682         }
 683
 684         // Bye-bye!
 685         int ret;
 686         do {
 687                 ret = close(client->sock);
 688         } while (ret == -1 && errno == EINTR);
 689
 690         if (ret == -1) {
 691                 perror("close");
 692         }
 693
 694         clients.erase(client->sock);
 695 }
 696
 697 Stream *Server::find_stream(const string &stream_id)
 698 {
 699         map<string, Stream *>::iterator it = streams.find(stream_id);
 700         assert(it != streams.end());
 701         return it->second;
 702 }
 703
 704 void Server::process_queued_data()
 705 {
 706         MutexLock lock(&queued_data_mutex);
 707
 708         for (size_t i = 0; i < queued_add_clients.size(); ++i) {
 709                 add_client(queued_add_clients[i]);
 710         }
 711         queued_add_clients.clear();
 712
 713         for (map<string, string>::iterator queued_it = queued_data.begin();
 714              queued_it != queued_data.end();
 715              ++queued_it) {
 716                 add_data(queued_it->first, queued_it->second.data(), queued_it->second.size());
 717         }
 718         queued_data.clear();
 719 }