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

   1 #include <stdio.h>
   2 #include <string.h>
   3 #include <stdint.h>
   4 #include <unistd.h>
   5 #include <assert.h>
   6 #include <arpa/inet.h>
   7 #include <sys/socket.h>
   8 #include <pthread.h>
   9 #include <sys/types.h>
  10 #include <sys/ioctl.h>
  11 #include <sys/types.h>
  12 #include <sys/socket.h>
  13 #include <netdb.h>
  14 #include <poll.h>
  15 #include <signal.h>
  16 #include <errno.h>
  17 #include <vector>
  18 #include <string>
  19 #include <map>
  20
  21 #include "metacube.h"
  22 #include "mutexlock.h"
  23 #include "httpinput.h"
  24 #include "server.h"
  25 #include "serverpool.h"
  26 #include "parse.h"
  27 #include "version.h"
  28 #include "state.pb.h"
  29
  30 using namespace std;
  31
  32 extern ServerPool *servers;
  33
  34 HTTPInput::HTTPInput(const string &stream_id, const string &url)
  35         : state(NOT_CONNECTED),
  36           stream_id(stream_id),
  37           url(url),
  38           has_metacube_header(false),
  39           sock(-1)
  40 {
  41 }
  42
  43 HTTPInput::HTTPInput(const InputProto &serialized)
  44         : state(State(serialized.state())),
  45           stream_id(serialized.stream_id()),
  46           url(serialized.url()),
  47           request(serialized.request()),
  48           request_bytes_sent(serialized.request_bytes_sent()),
  49           response(serialized.response()),
  50           http_header(serialized.http_header()),
  51           has_metacube_header(serialized.has_metacube_header()),
  52           sock(serialized.sock())
  53 {
  54         pending_data.resize(serialized.pending_data().size());
  55         memcpy(&pending_data[0], serialized.pending_data().data(), serialized.pending_data().size());
  56
  57         string protocol;
  58         parse_url(url, &protocol, &host, &port, &path);  // Don't care if it fails.
  59 }
  60
  61 void HTTPInput::close_socket()
  62 {
  63         int ret;
  64         do {
  65                 ret = close(sock);
  66         } while (ret == -1 && errno == EINTR);
  67
  68         if (ret == -1) {
  69                 perror("close()");
  70         }
  71 }
  72
  73 InputProto HTTPInput::serialize() const
  74 {
  75         InputProto serialized;
  76         serialized.set_state(state);
  77         serialized.set_stream_id(stream_id);
  78         serialized.set_url(url);
  79         serialized.set_request(request);
  80         serialized.set_request_bytes_sent(request_bytes_sent);
  81         serialized.set_response(response);
  82         serialized.set_http_header(http_header);
  83         serialized.set_pending_data(string(pending_data.begin(), pending_data.end()));
  84         serialized.set_has_metacube_header(has_metacube_header);
  85         serialized.set_sock(sock);
  86         return serialized;
  87 }
  88
  89 int HTTPInput::lookup_and_connect(const string &host, const string &port)
  90 {
  91         addrinfo *ai;
  92         int err = getaddrinfo(host.c_str(), port.c_str(), NULL, &ai);
  93         if (err == -1) {
  94                 fprintf(stderr, "WARNING: Lookup of '%s' failed (%s).\n",
  95                         host.c_str(), gai_strerror(err));
  96                 freeaddrinfo(ai);
  97                 return -1;
  98         }
  99
 100         // Connect to everything in turn until we have a socket.
 101         while (ai && !should_stop) {
 102                 int sock = socket(ai->ai_family, SOCK_STREAM, IPPROTO_TCP);
 103                 if (sock == -1) {
 104                         // Could be e.g. EPROTONOSUPPORT. The show must go on.
 105                         continue;
 106                 }
 107
 108                 do {
 109                         err = connect(sock, ai->ai_addr, ai->ai_addrlen);
 110                 } while (err == -1 && errno == EINTR);
 111
 112                 if (err != -1) {
 113                         freeaddrinfo(ai);
 114                         return sock;
 115                 }
 116
 117                 do {
 118                         err = close(sock);
 119                 } while (err == -1 && errno == EINTR);
 120
 121                 if (err == -1) {
 122                         perror("close");
 123                         // Can still continue.
 124                 }
 125
 126                 ai = ai->ai_next;
 127         }
 128
 129         // Give the last one as error.
 130         fprintf(stderr, "WARNING: Connect to '%s' failed (%s)\n",
 131                 host.c_str(), strerror(errno));
 132         freeaddrinfo(ai);
 133         return -1;
 134 }
 135
 136 bool HTTPInput::parse_response(const std::string &request)
 137 {
 138         vector<string> lines = split_lines(response);
 139         if (lines.empty()) {
 140                 fprintf(stderr, "WARNING: Empty HTTP response from input.\n");
 141                 return false;
 142         }
 143
 144         vector<string> first_line_tokens = split_tokens(lines[0]);
 145         if (first_line_tokens.size() < 2) {
 146                 fprintf(stderr, "WARNING: Malformed response line '%s' from input.\n",
 147                         lines[0].c_str());
 148                 return false;
 149         }
 150
 151         int response = atoi(first_line_tokens[1].c_str());
 152         if (response != 200) {
 153                 fprintf(stderr, "WARNING: Non-200 response '%s' from input.\n",
 154                         lines[0].c_str());
 155                 return false;
 156         }
 157
 158         multimap<string, string> parameters;
 159         for (size_t i = 1; i < lines.size(); ++i) {
 160                 size_t split = lines[i].find(":");
 161                 if (split == string::npos) {
 162                         fprintf(stderr, "WARNING: Ignoring malformed HTTP response line '%s'\n",
 163                                 lines[i].c_str());
 164                         continue;
 165                 }
 166
 167                 string key(lines[i].begin(), lines[i].begin() + split);
 168
 169                 // Skip any spaces after the colon.
 170                 do {
 171                         ++split;
 172                 } while (split < lines[i].size() && lines[i][split] == ' ');
 173
 174                 string value(lines[i].begin() + split, lines[i].end());
 175
 176                 // Remove “Content-encoding: metacube”.
 177                 // TODO: Make case-insensitive.
 178                 if (key == "Content-encoding" && value == "metacube") {
 179                         continue;
 180                 }
 181
 182                 parameters.insert(make_pair(key, value));
 183         }
 184
 185         // Change “Server: foo” to “Server: metacube/0.1 (reflecting: foo)”
 186         // TODO: Make case-insensitive.
 187         // XXX: Use a Via: instead?
 188         if (parameters.count("Server") == 0) {
 189                 parameters.insert(make_pair("Server", SERVER_IDENTIFICATION));
 190         } else {
 191                 for (multimap<string, string>::iterator it = parameters.begin();
 192                      it != parameters.end();
 193                      ++it) {
 194                         if (it->first != "Server") {
 195                                 continue;
 196                         }
 197                         it->second = SERVER_IDENTIFICATION " (reflecting: " + it->second + ")";
 198                 }
 199         }
 200
 201         // Construct the new HTTP header.
 202         http_header = "HTTP/1.0 200 OK\r\n";
 203         for (multimap<string, string>::iterator it = parameters.begin();
 204              it != parameters.end();
 205              ++it) {
 206                 http_header.append(it->first + ": " + it->second + "\r\n");
 207         }
 208         http_header.append("\r\n");
 209         servers->set_header(stream_id, http_header);
 210
 211         return true;
 212 }
 213
 214 void HTTPInput::do_work()
 215 {
 216         while (!should_stop) {
 217                 if (state == SENDING_REQUEST || state == RECEIVING_HEADER || state == RECEIVING_DATA) {
 218                         // Since we are non-blocking, we need to wait for the right state first.
 219                         // Wait up to 50 ms, then check should_stop.
 220                         pollfd pfd;
 221                         pfd.fd = sock;
 222                         pfd.events = (state == SENDING_REQUEST) ? POLLOUT : POLLIN;
 223                         pfd.events |= POLLRDHUP;
 224
 225                         int nfds = poll(&pfd, 1, 50);
 226                         if (nfds == 0 || (nfds == -1 && errno == EINTR)) {
 227                                 continue;
 228                         }
 229                         if (nfds == -1) {
 230                                 perror("poll");
 231                                 state = CLOSING_SOCKET;
 232                         }
 233                 }
 234
 235                 switch (state) {
 236                 case NOT_CONNECTED:
 237                         request.clear();
 238                         request_bytes_sent = 0;
 239                         response.clear();
 240                         pending_data.clear();
 241
 242                         {
 243                                 string protocol;  // Thrown away.
 244                                 if (!parse_url(url, &protocol, &host, &port, &path)) {
 245                                         fprintf(stderr, "Failed to parse URL '%s'\n", url.c_str());
 246                                         break;
 247                                 }
 248                         }
 249
 250                         sock = lookup_and_connect(host, port);
 251                         if (sock != -1) {
 252                                 // Yay, successful connect. Try to set it as nonblocking.
 253                                 int one = 1;
 254                                 if (ioctl(sock, FIONBIO, &one) == -1) {
 255                                         perror("ioctl(FIONBIO)");
 256                                         state = CLOSING_SOCKET;
 257                                 } else {
 258                                         state = SENDING_REQUEST;
 259                                         request = "GET " + path + " HTTP/1.0\r\nUser-Agent: cubemap\r\n\r\n";
 260                                         request_bytes_sent = 0;
 261                                 }
 262                         }
 263                         break;
 264                 case SENDING_REQUEST: {
 265                         size_t to_send = request.size() - request_bytes_sent;
 266                         int ret;
 267
 268                         do {
 269                                 ret = write(sock, request.data() + request_bytes_sent, to_send);
 270                         } while (ret == -1 && errno == EINTR);
 271
 272                         if (ret == -1) {
 273                                 perror("write");
 274                                 state = CLOSING_SOCKET;
 275                                 continue;
 276                         }
 277
 278                         assert(ret >= 0);
 279                         request_bytes_sent += ret;
 280
 281                         if (request_bytes_sent == request.size()) {
 282                                 state = RECEIVING_HEADER;
 283                         }
 284                         break;
 285                 }
 286                 case RECEIVING_HEADER: {
 287                         char buf[4096];
 288                         int ret;
 289
 290                         do {
 291                                 ret = read(sock, buf, sizeof(buf));
 292                         } while (ret == -1 && errno == EINTR);
 293
 294                         if (ret == -1) {
 295                                 perror("read");
 296                                 state = CLOSING_SOCKET;
 297                                 continue;
 298                         }
 299
 300                         if (ret == 0) {
 301                                 // This really shouldn't happen...
 302                                 fprintf(stderr, "Socket unexpectedly closed while reading header\n");
 303                                 state = CLOSING_SOCKET;
 304                                 continue;
 305                         }
 306
 307                         RequestParseStatus status = wait_for_double_newline(&response, buf, ret);
 308
 309                         if (status == RP_OUT_OF_SPACE) {
 310                                 fprintf(stderr, "WARNING: fd %d sent overlong response!\n", sock);
 311                                 state = CLOSING_SOCKET;
 312                                 continue;
 313                         } else if (status == RP_NOT_FINISHED_YET) {
 314                                 continue;
 315                         }
 316
 317                         // OK, so we're fine, but there might be some of the actual data after the response.
 318                         // We'll need to deal with that separately.
 319                         string extra_data;
 320                         if (status == RP_EXTRA_DATA) {
 321                                 char *ptr = static_cast<char *>(
 322                                         memmem(response.data(), response.size(), "\r\n\r\n", 4));
 323                                 assert(ptr != NULL);
 324                                 extra_data = string(ptr, &response[0] + response.size());
 325                                 response.resize(ptr - response.data());
 326                         }
 327
 328                         if (!parse_response(response)) {
 329                                 state = CLOSING_SOCKET;
 330                                 continue;
 331                         }
 332
 333                         if (!extra_data.empty()) {
 334                                 process_data(&extra_data[0], extra_data.size());
 335                         }
 336
 337                         state = RECEIVING_DATA;
 338                         break;
 339                 }
 340                 case RECEIVING_DATA: {
 341                         char buf[4096];
 342                         int ret;
 343
 344                         do {
 345                                 ret = read(sock, buf, sizeof(buf));
 346                         } while (ret == -1 && errno == EINTR);
 347
 348                         if (ret == -1) {
 349                                 perror("read");
 350                                 state = CLOSING_SOCKET;
 351                                 continue;
 352                         }
 353
 354                         if (ret == 0) {
 355                                 // This really shouldn't happen...
 356                                 fprintf(stderr, "Socket unexpectedly closed while reading header\n");
 357                                 state = CLOSING_SOCKET;
 358                                 continue;
 359                         }
 360
 361                         process_data(buf, ret);
 362                         break;
 363                 }
 364                 case CLOSING_SOCKET: {
 365                         int err;
 366                         do {
 367                                 err = close(sock);
 368                         } while (err == -1 && errno == EINTR);
 369
 370                         if (err == -1) {
 371                                 perror("close");
 372                         }
 373
 374                         state = NOT_CONNECTED;
 375                         break;
 376                 }
 377                 default:
 378                         assert(false);
 379                 }
 380
 381                 // If we are still in NOT_CONNECTED, either something went wrong,
 382                 // or the connection just got closed.
 383                 // The earlier steps have already given the error message, if any.
 384                 if (state == NOT_CONNECTED && !should_stop) {
 385                         fprintf(stderr, "Waiting 0.2 second and restarting...\n");
 386                         usleep(200000);
 387                 }
 388         }
 389 }
 390
 391 void HTTPInput::process_data(char *ptr, size_t bytes)
 392 {
 393         pending_data.insert(pending_data.end(), ptr, ptr + bytes);
 394
 395         for ( ;; ) {
 396                 // If we don't have enough data (yet) for even the Metacube header, just return.
 397                 if (pending_data.size() < sizeof(metacube_block_header)) {
 398                         return;
 399                 }
 400
 401                 // Make sure we have the Metacube sync header at the start.
 402                 // We may need to skip over junk data (it _should_ not happen, though).
 403                 if (!has_metacube_header) {
 404                         char *ptr = static_cast<char *>(
 405                                 memmem(pending_data.data(), pending_data.size(),
 406                                        METACUBE_SYNC, strlen(METACUBE_SYNC)));
 407                         if (ptr == NULL) {
 408                                 // OK, so we didn't find the sync marker. We know then that
 409                                 // we do not have the _full_ marker in the buffer, but we
 410                                 // could have N-1 bytes. Drop everything before that,
 411                                 // and then give up.
 412                                 drop_pending_data(pending_data.size() - (strlen(METACUBE_SYNC) - 1));
 413                                 return;
 414                         } else {
 415                                 // Yay, we found the header. Drop everything (if anything) before it.
 416                                 drop_pending_data(ptr - pending_data.data());
 417                                 has_metacube_header = true;
 418
 419                                 // Re-check that we have the entire header; we could have dropped data.
 420                                 if (pending_data.size() < sizeof(metacube_block_header)) {
 421                                         return;
 422                                 }
 423                         }
 424                 }
 425
 426                 // Now it's safe to read the header.
 427                 metacube_block_header *hdr = reinterpret_cast<metacube_block_header *>(pending_data.data());
 428                 assert(memcmp(hdr->sync, METACUBE_SYNC, sizeof(hdr->sync)) == 0);
 429                 uint32_t size = ntohl(hdr->size);
 430                 uint32_t flags = ntohl(hdr->flags);
 431
 432                 // See if we have the entire block. If not, wait for more data.
 433                 if (pending_data.size() < sizeof(metacube_block_header) + size) {
 434                         return;
 435                 }
 436
 437                 // Send this block on to the data.
 438                 char *inner_data = pending_data.data() + sizeof(metacube_block_header);
 439                 if (flags & METACUBE_FLAGS_HEADER) {
 440                         string header(inner_data, inner_data + size);
 441                         servers->set_header(stream_id, http_header + header);
 442                 } else {
 443                         servers->add_data(stream_id, inner_data, size);
 444                 }
 445
 446                 // Consume the block. This isn't the most efficient way of dealing with things
 447                 // should we have many blocks, but these routines don't need to be too efficient
 448                 // anyway.
 449                 pending_data.erase(pending_data.begin(), pending_data.begin() + sizeof(metacube_block_header) + size);
 450                 has_metacube_header = false;
 451         }
 452 }
 453
 454 void HTTPInput::drop_pending_data(size_t num_bytes)
 455 {
 456         if (num_bytes == 0) {
 457                 return;
 458         }
 459         fprintf(stderr, "Warning: Dropping %lld junk bytes from stream, maybe it is not a Metacube stream?\n",
 460                 (long long)num_bytes);
 461         pending_data.erase(pending_data.begin(), pending_data.begin() + num_bytes);
 462 }
 463