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

   1 #include <assert.h>
   2 #include <errno.h>
   3 #include <netdb.h>
   4 #include <netinet/in.h>
   5 #include <poll.h>
   6 #include <stdint.h>
   7 #include <stdio.h>
   8 #include <stdlib.h>
   9 #include <string.h>
  10 #include <sys/ioctl.h>
  11 #include <sys/socket.h>
  12 #include <unistd.h>
  13 #include <map>
  14 #include <string>
  15 #include <utility>
  16 #include <vector>
  17
  18 #include "httpinput.h"
  19 #include "log.h"
  20 #include "metacube.h"
  21 #include "parse.h"
  22 #include "serverpool.h"
  23 #include "state.pb.h"
  24 #include "version.h"
  25
  26 using namespace std;
  27
  28 extern ServerPool *servers;
  29
  30 HTTPInput::HTTPInput(const string &url)
  31         : state(NOT_CONNECTED),
  32           url(url),
  33           has_metacube_header(false),
  34           sock(-1)
  35 {
  36 }
  37
  38 HTTPInput::HTTPInput(const InputProto &serialized)
  39         : state(State(serialized.state())),
  40           url(serialized.url()),
  41           request(serialized.request()),
  42           request_bytes_sent(serialized.request_bytes_sent()),
  43           response(serialized.response()),
  44           http_header(serialized.http_header()),
  45           has_metacube_header(serialized.has_metacube_header()),
  46           sock(serialized.sock())
  47 {
  48         pending_data.resize(serialized.pending_data().size());
  49         memcpy(&pending_data[0], serialized.pending_data().data(), serialized.pending_data().size());
  50
  51         string protocol;
  52         parse_url(url, &protocol, &host, &port, &path);  // Don't care if it fails.
  53
  54         // Older versions stored the extra \r\n in the HTTP header.
  55         // Strip it if we find it.
  56         if (http_header.size() >= 4 &&
  57             memcmp(http_header.data() + http_header.size() - 4, "\r\n\r\n", 4) == 0) {
  58                 http_header.resize(http_header.size() - 2);
  59         }
  60 }
  61
  62 void HTTPInput::close_socket()
  63 {
  64         int ret;
  65         do {
  66                 ret = close(sock);
  67         } while (ret == -1 && errno == EINTR);
  68
  69         if (ret == -1) {
  70                 log_perror("close()");
  71         }
  72 }
  73
  74 InputProto HTTPInput::serialize() const
  75 {
  76         InputProto serialized;
  77         serialized.set_state(state);
  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                 log(WARNING, "[%s] Lookup of '%s' failed (%s).",
  95                         url.c_str(), host.c_str(), gai_strerror(err));
  96                 freeaddrinfo(ai);
  97                 return -1;
  98         }
  99
 100         addrinfo *base_ai = ai;
 101
 102         // Connect to everything in turn until we have a socket.
 103         while (ai && !should_stop) {
 104                 int sock = socket(ai->ai_family, SOCK_STREAM, IPPROTO_TCP);
 105                 if (sock == -1) {
 106                         // Could be e.g. EPROTONOSUPPORT. The show must go on.
 107                         continue;
 108                 }
 109
 110                 do {
 111                         err = connect(sock, ai->ai_addr, ai->ai_addrlen);
 112                 } while (err == -1 && errno == EINTR);
 113
 114                 if (err != -1) {
 115                         freeaddrinfo(base_ai);
 116                         return sock;
 117                 }
 118
 119                 do {
 120                         err = close(sock);
 121                 } while (err == -1 && errno == EINTR);
 122
 123                 if (err == -1) {
 124                         log_perror("close");
 125                         // Can still continue.
 126                 }
 127
 128                 ai = ai->ai_next;
 129         }
 130
 131         // Give the last one as error.
 132         log(WARNING, "[%s] Connect to '%s' failed (%s)",
 133                 url.c_str(), host.c_str(), strerror(errno));
 134         freeaddrinfo(base_ai);
 135         return -1;
 136 }
 137
 138 bool HTTPInput::parse_response(const std::string &request)
 139 {
 140         vector<string> lines = split_lines(response);
 141         if (lines.empty()) {
 142                 log(WARNING, "[%s] Empty HTTP response from input.", url.c_str());
 143                 return false;
 144         }
 145
 146         vector<string> first_line_tokens = split_tokens(lines[0]);
 147         if (first_line_tokens.size() < 2) {
 148                 log(WARNING, "[%s] Malformed response line '%s' from input.",
 149                         url.c_str(), lines[0].c_str());
 150                 return false;
 151         }
 152
 153         int response = atoi(first_line_tokens[1].c_str());
 154         if (response != 200) {
 155                 log(WARNING, "[%s] Non-200 response '%s' from input.",
 156                         url.c_str(), lines[0].c_str());
 157                 return false;
 158         }
 159
 160         multimap<string, string> parameters;
 161         for (size_t i = 1; i < lines.size(); ++i) {
 162                 size_t split = lines[i].find(":");
 163                 if (split == string::npos) {
 164                         log(WARNING, "[%s] Ignoring malformed HTTP response line '%s'",
 165                                 url.c_str(), lines[i].c_str());
 166                         continue;
 167                 }
 168
 169                 string key(lines[i].begin(), lines[i].begin() + split);
 170
 171                 // Skip any spaces after the colon.
 172                 do {
 173                         ++split;
 174                 } while (split < lines[i].size() && lines[i][split] == ' ');
 175
 176                 string value(lines[i].begin() + split, lines[i].end());
 177
 178                 // Remove “Content-encoding: metacube”.
 179                 // TODO: Make case-insensitive.
 180                 if (key == "Content-encoding" && value == "metacube") {
 181                         continue;
 182                 }
 183
 184                 parameters.insert(make_pair(key, value));
 185         }
 186
 187         // Change “Server: foo” to “Server: metacube/0.1 (reflecting: foo)”
 188         // TODO: Make case-insensitive.
 189         // XXX: Use a Via: instead?
 190         if (parameters.count("Server") == 0) {
 191                 parameters.insert(make_pair("Server", SERVER_IDENTIFICATION));
 192         } else {
 193                 for (multimap<string, string>::iterator it = parameters.begin();
 194                      it != parameters.end();
 195                      ++it) {
 196                         if (it->first != "Server") {
 197                                 continue;
 198                         }
 199                         it->second = SERVER_IDENTIFICATION " (reflecting: " + it->second + ")";
 200                 }
 201         }
 202
 203         // Set “Connection: close”.
 204         // TODO: Make case-insensitive.
 205         parameters.erase("Connection");
 206         parameters.insert(make_pair("Connection", "close"));
 207
 208         // Construct the new HTTP header.
 209         http_header = "HTTP/1.0 200 OK\r\n";
 210         for (multimap<string, string>::iterator it = parameters.begin();
 211              it != parameters.end();
 212              ++it) {
 213                 http_header.append(it->first + ": " + it->second + "\r\n");
 214         }
 215
 216         for (size_t i = 0; i < stream_ids.size(); ++i) {
 217                 servers->set_header(stream_ids[i], http_header, "");
 218         }
 219
 220         return true;
 221 }
 222
 223 void HTTPInput::do_work()
 224 {
 225         while (!should_stop) {
 226                 if (state == SENDING_REQUEST || state == RECEIVING_HEADER || state == RECEIVING_DATA) {
 227                         // Since we are non-blocking, we need to wait for the right state first.
 228                         // Wait up to 50 ms, then check should_stop.
 229                         pollfd pfd;
 230                         pfd.fd = sock;
 231                         pfd.events = (state == SENDING_REQUEST) ? POLLOUT : POLLIN;
 232                         pfd.events |= POLLRDHUP;
 233
 234                         int nfds = poll(&pfd, 1, 50);
 235                         if (nfds == 0 || (nfds == -1 && errno == EINTR)) {
 236                                 continue;
 237                         }
 238                         if (nfds == -1) {
 239                                 log_perror("poll");
 240                                 state = CLOSING_SOCKET;
 241                         }
 242                 }
 243
 244                 switch (state) {
 245                 case NOT_CONNECTED:
 246                         request.clear();
 247                         request_bytes_sent = 0;
 248                         response.clear();
 249                         pending_data.clear();
 250                         for (size_t i = 0; i < stream_ids.size(); ++i) {
 251                                 servers->set_header(stream_ids[i], "", "");
 252                         }
 253
 254                         {
 255                                 string protocol;  // Thrown away.
 256                                 if (!parse_url(url, &protocol, &host, &port, &path)) {
 257                                         log(WARNING, "[%s] Failed to parse URL '%s'", url.c_str(), url.c_str());
 258                                         break;
 259                                 }
 260                         }
 261
 262                         sock = lookup_and_connect(host, port);
 263                         if (sock != -1) {
 264                                 // Yay, successful connect. Try to set it as nonblocking.
 265                                 int one = 1;
 266                                 if (ioctl(sock, FIONBIO, &one) == -1) {
 267                                         log_perror("ioctl(FIONBIO)");
 268                                         state = CLOSING_SOCKET;
 269                                 } else {
 270                                         state = SENDING_REQUEST;
 271                                         request = "GET " + path + " HTTP/1.0\r\nUser-Agent: cubemap\r\n\r\n";
 272                                         request_bytes_sent = 0;
 273                                 }
 274                         }
 275                         break;
 276                 case SENDING_REQUEST: {
 277                         size_t to_send = request.size() - request_bytes_sent;
 278                         int ret;
 279
 280                         do {
 281                                 ret = write(sock, request.data() + request_bytes_sent, to_send);
 282                         } while (ret == -1 && errno == EINTR);
 283
 284                         if (ret == -1) {
 285                                 log_perror("write");
 286                                 state = CLOSING_SOCKET;
 287                                 continue;
 288                         }
 289
 290                         assert(ret >= 0);
 291                         request_bytes_sent += ret;
 292
 293                         if (request_bytes_sent == request.size()) {
 294                                 state = RECEIVING_HEADER;
 295                         }
 296                         break;
 297                 }
 298                 case RECEIVING_HEADER: {
 299                         char buf[4096];
 300                         int ret;
 301
 302                         do {
 303                                 ret = read(sock, buf, sizeof(buf));
 304                         } while (ret == -1 && errno == EINTR);
 305
 306                         if (ret == -1) {
 307                                 log_perror("read");
 308                                 state = CLOSING_SOCKET;
 309                                 continue;
 310                         }
 311
 312                         if (ret == 0) {
 313                                 // This really shouldn't happen...
 314                                 log(ERROR, "[%s] Socket unexpectedly closed while reading header",
 315                                            url.c_str());
 316                                 state = CLOSING_SOCKET;
 317                                 continue;
 318                         }
 319
 320                         RequestParseStatus status = wait_for_double_newline(&response, buf, ret);
 321
 322                         if (status == RP_OUT_OF_SPACE) {
 323                                 log(WARNING, "[%s] Sever sent overlong HTTP response!", url.c_str());
 324                                 state = CLOSING_SOCKET;
 325                                 continue;
 326                         } else if (status == RP_NOT_FINISHED_YET) {
 327                                 continue;
 328                         }
 329
 330                         // OK, so we're fine, but there might be some of the actual data after the response.
 331                         // We'll need to deal with that separately.
 332                         string extra_data;
 333                         if (status == RP_EXTRA_DATA) {
 334                                 char *ptr = static_cast<char *>(
 335                                         memmem(response.data(), response.size(), "\r\n\r\n", 4));
 336                                 assert(ptr != NULL);
 337                                 extra_data = string(ptr, &response[0] + response.size());
 338                                 response.resize(ptr - response.data());
 339                         }
 340
 341                         if (!parse_response(response)) {
 342                                 state = CLOSING_SOCKET;
 343                                 continue;
 344                         }
 345
 346                         if (!extra_data.empty()) {
 347                                 process_data(&extra_data[0], extra_data.size());
 348                         }
 349
 350                         log(INFO, "[%s] Connected to '%s', receiving data.",
 351                                    url.c_str(), url.c_str());
 352                         state = RECEIVING_DATA;
 353                         break;
 354                 }
 355                 case RECEIVING_DATA: {
 356                         char buf[4096];
 357                         int ret;
 358
 359                         do {
 360                                 ret = read(sock, buf, sizeof(buf));
 361                         } while (ret == -1 && errno == EINTR);
 362
 363                         if (ret == -1) {
 364                                 log_perror("read");
 365                                 state = CLOSING_SOCKET;
 366                                 continue;
 367                         }
 368
 369                         if (ret == 0) {
 370                                 // This really shouldn't happen...
 371                                 log(ERROR, "[%s] Socket unexpectedly closed while reading header",
 372                                            url.c_str());
 373                                 state = CLOSING_SOCKET;
 374                                 continue;
 375                         }
 376
 377                         process_data(buf, ret);
 378                         break;
 379                 }
 380                 case CLOSING_SOCKET: {
 381                         int err;
 382                         do {
 383                                 err = close(sock);
 384                         } while (err == -1 && errno == EINTR);
 385
 386                         if (err == -1) {
 387                                 log_perror("close");
 388                         }
 389
 390                         state = NOT_CONNECTED;
 391                         break;
 392                 }
 393                 default:
 394                         assert(false);
 395                 }
 396
 397                 // If we are still in NOT_CONNECTED, either something went wrong,
 398                 // or the connection just got closed.
 399                 // The earlier steps have already given the error message, if any.
 400                 if (state == NOT_CONNECTED && !should_stop) {
 401                         log(INFO, "[%s] Waiting 0.2 second and restarting...", url.c_str());
 402                         usleep(200000);
 403                 }
 404         }
 405 }
 406
 407 void HTTPInput::process_data(char *ptr, size_t bytes)
 408 {
 409         pending_data.insert(pending_data.end(), ptr, ptr + bytes);
 410
 411         for ( ;; ) {
 412                 // If we don't have enough data (yet) for even the Metacube header, just return.
 413                 if (pending_data.size() < sizeof(metacube_block_header)) {
 414                         return;
 415                 }
 416
 417                 // Make sure we have the Metacube sync header at the start.
 418                 // We may need to skip over junk data (it _should_ not happen, though).
 419                 if (!has_metacube_header) {
 420                         char *ptr = static_cast<char *>(
 421                                 memmem(pending_data.data(), pending_data.size(),
 422                                        METACUBE_SYNC, strlen(METACUBE_SYNC)));
 423                         if (ptr == NULL) {
 424                                 // OK, so we didn't find the sync marker. We know then that
 425                                 // we do not have the _full_ marker in the buffer, but we
 426                                 // could have N-1 bytes. Drop everything before that,
 427                                 // and then give up.
 428                                 drop_pending_data(pending_data.size() - (strlen(METACUBE_SYNC) - 1));
 429                                 return;
 430                         } else {
 431                                 // Yay, we found the header. Drop everything (if anything) before it.
 432                                 drop_pending_data(ptr - pending_data.data());
 433                                 has_metacube_header = true;
 434
 435                                 // Re-check that we have the entire header; we could have dropped data.
 436                                 if (pending_data.size() < sizeof(metacube_block_header)) {
 437                                         return;
 438                                 }
 439                         }
 440                 }
 441
 442                 // Now it's safe to read the header.
 443                 metacube_block_header *hdr = reinterpret_cast<metacube_block_header *>(pending_data.data());
 444                 assert(memcmp(hdr->sync, METACUBE_SYNC, sizeof(hdr->sync)) == 0);
 445                 uint32_t size = ntohl(hdr->size);
 446                 uint32_t flags = ntohl(hdr->flags);
 447
 448                 // See if we have the entire block. If not, wait for more data.
 449                 if (pending_data.size() < sizeof(metacube_block_header) + size) {
 450                         return;
 451                 }
 452
 453                 // Send this block on to the data.
 454                 char *inner_data = pending_data.data() + sizeof(metacube_block_header);
 455                 if (flags & METACUBE_FLAGS_HEADER) {
 456                         string header(inner_data, inner_data + size);
 457                         for (size_t i = 0; i < stream_ids.size(); ++i) {
 458                                 servers->set_header(stream_ids[i], http_header, header);
 459                         }
 460                 } else {
 461                         for (size_t i = 0; i < stream_ids.size(); ++i) {
 462                                 servers->add_data(stream_ids[i], inner_data, size);
 463                         }
 464                 }
 465
 466                 // Consume the block. This isn't the most efficient way of dealing with things
 467                 // should we have many blocks, but these routines don't need to be too efficient
 468                 // anyway.
 469                 pending_data.erase(pending_data.begin(), pending_data.begin() + sizeof(metacube_block_header) + size);
 470                 has_metacube_header = false;
 471         }
 472 }
 473
 474 void HTTPInput::drop_pending_data(size_t num_bytes)
 475 {
 476         if (num_bytes == 0) {
 477                 return;
 478         }
 479         log(WARNING, "[%s] Dropping %lld junk bytes from stream, maybe it is not a Metacube stream?",
 480                 url.c_str(), (long long)num_bytes);
 481         pending_data.erase(pending_data.begin(), pending_data.begin() + num_bytes);
 482 }
 483