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 <stdlib.h>
   8 #include <string.h>
   9 #include <sys/ioctl.h>
  10 #include <sys/socket.h>
  11 #include <time.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 "util.h"
  25 #include "version.h"
  26
  27 using namespace std;
  28
  29 extern ServerPool *servers;
  30
  31 HTTPInput::HTTPInput(const string &url)
  32         : state(NOT_CONNECTED),
  33           url(url),
  34           has_metacube_header(false),
  35           sock(-1)
  36 {
  37 }
  38
  39 HTTPInput::HTTPInput(const InputProto &serialized)
  40         : state(State(serialized.state())),
  41           url(serialized.url()),
  42           request(serialized.request()),
  43           request_bytes_sent(serialized.request_bytes_sent()),
  44           response(serialized.response()),
  45           http_header(serialized.http_header()),
  46           has_metacube_header(serialized.has_metacube_header()),
  47           sock(serialized.sock())
  48 {
  49         pending_data.resize(serialized.pending_data().size());
  50         memcpy(&pending_data[0], serialized.pending_data().data(), serialized.pending_data().size());
  51
  52         string protocol;
  53         parse_url(url, &protocol, &host, &port, &path);  // Don't care if it fails.
  54
  55         // Older versions stored the extra \r\n in the HTTP header.
  56         // Strip it if we find it.
  57         if (http_header.size() >= 4 &&
  58             memcmp(http_header.data() + http_header.size() - 4, "\r\n\r\n", 4) == 0) {
  59                 http_header.resize(http_header.size() - 2);
  60         }
  61 }
  62
  63 void HTTPInput::close_socket()
  64 {
  65         if (sock != -1) {
  66                 safe_close(sock);
  67         }
  68 }
  69
  70 InputProto HTTPInput::serialize() const
  71 {
  72         InputProto serialized;
  73         serialized.set_state(state);
  74         serialized.set_url(url);
  75         serialized.set_request(request);
  76         serialized.set_request_bytes_sent(request_bytes_sent);
  77         serialized.set_response(response);
  78         serialized.set_http_header(http_header);
  79         serialized.set_pending_data(string(pending_data.begin(), pending_data.end()));
  80         serialized.set_has_metacube_header(has_metacube_header);
  81         serialized.set_sock(sock);
  82         return serialized;
  83 }
  84
  85 int HTTPInput::lookup_and_connect(const string &host, const string &port)
  86 {
  87         addrinfo *ai;
  88         int err = getaddrinfo(host.c_str(), port.c_str(), NULL, &ai);
  89         if (err != 0) {
  90                 log(WARNING, "[%s] Lookup of '%s' failed (%s).",
  91                         url.c_str(), host.c_str(), gai_strerror(err));
  92                 return -1;
  93         }
  94
  95         addrinfo *base_ai = ai;
  96
  97         // Connect to everything in turn until we have a socket.
  98         for ( ; ai && !should_stop(); ai = ai->ai_next) {
  99                 int sock = socket(ai->ai_family, SOCK_STREAM, IPPROTO_TCP);
 100                 if (sock == -1) {
 101                         // Could be e.g. EPROTONOSUPPORT. The show must go on.
 102                         continue;
 103                 }
 104
 105                 // Now do a non-blocking connect. This is important because we want to be able to be
 106                 // woken up, even though it's rather cumbersome.
 107
 108                 // Set the socket as nonblocking.
 109                 int one = 1;
 110                 if (ioctl(sock, FIONBIO, &one) == -1) {
 111                         log_perror("ioctl(FIONBIO)");
 112                         safe_close(sock);
 113                         return -1;
 114                 }
 115
 116                 // Do a non-blocking connect.
 117                 do {
 118                         err = connect(sock, ai->ai_addr, ai->ai_addrlen);
 119                 } while (err == -1 && errno == EINTR);
 120
 121                 if (err == -1 && errno != EINPROGRESS) {
 122                         log_perror("connect");
 123                         safe_close(sock);
 124                         continue;
 125                 }
 126
 127                 // Wait for the connect to complete, or an error to happen.
 128                 for ( ;; ) {
 129                         bool complete = wait_for_activity(sock, POLLIN | POLLOUT, NULL);
 130                         if (should_stop()) {
 131                                 safe_close(sock);
 132                                 return -1;
 133                         }
 134                         if (complete) {
 135                                 break;
 136                         }
 137                 }
 138
 139                 // Check whether it ended in an error or not.
 140                 socklen_t err_size = sizeof(err);
 141                 if (getsockopt(sock, SOL_SOCKET, SO_ERROR, &err, &err_size) == -1) {
 142                         log_perror("getsockopt");
 143                         safe_close(sock);
 144                         continue;
 145                 }
 146
 147                 errno = err;
 148
 149                 if (err == 0) {
 150                         // Successful connect.
 151                         freeaddrinfo(base_ai);
 152                         return sock;
 153                 }
 154
 155                 safe_close(sock);
 156         }
 157
 158         // Give the last one as error.
 159         log(WARNING, "[%s] Connect to '%s' failed (%s)",
 160                 url.c_str(), host.c_str(), strerror(errno));
 161         freeaddrinfo(base_ai);
 162         return -1;
 163 }
 164
 165 bool HTTPInput::parse_response(const std::string &request)
 166 {
 167         vector<string> lines = split_lines(response);
 168         if (lines.empty()) {
 169                 log(WARNING, "[%s] Empty HTTP response from input.", url.c_str());
 170                 return false;
 171         }
 172
 173         vector<string> first_line_tokens = split_tokens(lines[0]);
 174         if (first_line_tokens.size() < 2) {
 175                 log(WARNING, "[%s] Malformed response line '%s' from input.",
 176                         url.c_str(), lines[0].c_str());
 177                 return false;
 178         }
 179
 180         int response = atoi(first_line_tokens[1].c_str());
 181         if (response != 200) {
 182                 log(WARNING, "[%s] Non-200 response '%s' from input.",
 183                         url.c_str(), lines[0].c_str());
 184                 return false;
 185         }
 186
 187         multimap<string, string> parameters;
 188         for (size_t i = 1; i < lines.size(); ++i) {
 189                 size_t split = lines[i].find(":");
 190                 if (split == string::npos) {
 191                         log(WARNING, "[%s] Ignoring malformed HTTP response line '%s'",
 192                                 url.c_str(), lines[i].c_str());
 193                         continue;
 194                 }
 195
 196                 string key(lines[i].begin(), lines[i].begin() + split);
 197
 198                 // Skip any spaces after the colon.
 199                 do {
 200                         ++split;
 201                 } while (split < lines[i].size() && lines[i][split] == ' ');
 202
 203                 string value(lines[i].begin() + split, lines[i].end());
 204
 205                 // Remove “Content-encoding: metacube”.
 206                 // TODO: Make case-insensitive.
 207                 if (key == "Content-encoding" && value == "metacube") {
 208                         continue;
 209                 }
 210
 211                 parameters.insert(make_pair(key, value));
 212         }
 213
 214         // Change “Server: foo” to “Server: metacube/0.1 (reflecting: foo)”
 215         // TODO: Make case-insensitive.
 216         // XXX: Use a Via: instead?
 217         if (parameters.count("Server") == 0) {
 218                 parameters.insert(make_pair("Server", SERVER_IDENTIFICATION));
 219         } else {
 220                 for (multimap<string, string>::iterator it = parameters.begin();
 221                      it != parameters.end();
 222                      ++it) {
 223                         if (it->first != "Server") {
 224                                 continue;
 225                         }
 226                         it->second = SERVER_IDENTIFICATION " (reflecting: " + it->second + ")";
 227                 }
 228         }
 229
 230         // Set “Connection: close”.
 231         // TODO: Make case-insensitive.
 232         parameters.erase("Connection");
 233         parameters.insert(make_pair("Connection", "close"));
 234
 235         // Construct the new HTTP header.
 236         http_header = "HTTP/1.0 200 OK\r\n";
 237         for (multimap<string, string>::iterator it = parameters.begin();
 238              it != parameters.end();
 239              ++it) {
 240                 http_header.append(it->first + ": " + it->second + "\r\n");
 241         }
 242
 243         for (size_t i = 0; i < stream_indices.size(); ++i) {
 244                 servers->set_header(stream_indices[i], http_header, "");
 245         }
 246
 247         return true;
 248 }
 249
 250 void HTTPInput::do_work()
 251 {
 252         while (!should_stop()) {
 253                 if (state == SENDING_REQUEST || state == RECEIVING_HEADER || state == RECEIVING_DATA) {
 254                         bool activity = wait_for_activity(sock, (state == SENDING_REQUEST) ? POLLOUT : POLLIN, NULL);
 255                         if (!activity) {
 256                                 // Most likely, should_stop was set.
 257                                 continue;
 258                         }
 259                 }
 260
 261                 switch (state) {
 262                 case NOT_CONNECTED:
 263                         request.clear();
 264                         request_bytes_sent = 0;
 265                         response.clear();
 266                         pending_data.clear();
 267                         has_metacube_header = false;
 268                         for (size_t i = 0; i < stream_indices.size(); ++i) {
 269                                 servers->set_header(stream_indices[i], "", "");
 270                         }
 271
 272                         {
 273                                 string protocol;  // Thrown away.
 274                                 if (!parse_url(url, &protocol, &host, &port, &path)) {
 275                                         log(WARNING, "[%s] Failed to parse URL '%s'", url.c_str(), url.c_str());
 276                                         break;
 277                                 }
 278                         }
 279
 280                         sock = lookup_and_connect(host, port);
 281                         if (sock != -1) {
 282                                 // Yay, successful connect. Try to set it as nonblocking.
 283                                 int one = 1;
 284                                 if (ioctl(sock, FIONBIO, &one) == -1) {
 285                                         log_perror("ioctl(FIONBIO)");
 286                                         state = CLOSING_SOCKET;
 287                                 } else {
 288                                         state = SENDING_REQUEST;
 289                                         request = "GET " + path + " HTTP/1.0\r\nUser-Agent: cubemap\r\n\r\n";
 290                                         request_bytes_sent = 0;
 291                                 }
 292                         }
 293                         break;
 294                 case SENDING_REQUEST: {
 295                         size_t to_send = request.size() - request_bytes_sent;
 296                         int ret;
 297
 298                         do {
 299                                 ret = write(sock, request.data() + request_bytes_sent, to_send);
 300                         } while (ret == -1 && errno == EINTR);
 301
 302                         if (ret == -1) {
 303                                 log_perror("write");
 304                                 state = CLOSING_SOCKET;
 305                                 continue;
 306                         }
 307
 308                         assert(ret >= 0);
 309                         request_bytes_sent += ret;
 310
 311                         if (request_bytes_sent == request.size()) {
 312                                 state = RECEIVING_HEADER;
 313                         }
 314                         break;
 315                 }
 316                 case RECEIVING_HEADER: {
 317                         char buf[4096];
 318                         int ret;
 319
 320                         do {
 321                                 ret = read(sock, buf, sizeof(buf));
 322                         } while (ret == -1 && errno == EINTR);
 323
 324                         if (ret == -1) {
 325                                 log_perror("read");
 326                                 state = CLOSING_SOCKET;
 327                                 continue;
 328                         }
 329
 330                         if (ret == 0) {
 331                                 // This really shouldn't happen...
 332                                 log(ERROR, "[%s] Socket unexpectedly closed while reading header",
 333                                            url.c_str());
 334                                 state = CLOSING_SOCKET;
 335                                 continue;
 336                         }
 337
 338                         RequestParseStatus status = wait_for_double_newline(&response, buf, ret);
 339
 340                         if (status == RP_OUT_OF_SPACE) {
 341                                 log(WARNING, "[%s] Sever sent overlong HTTP response!", url.c_str());
 342                                 state = CLOSING_SOCKET;
 343                                 continue;
 344                         } else if (status == RP_NOT_FINISHED_YET) {
 345                                 continue;
 346                         }
 347
 348                         // OK, so we're fine, but there might be some of the actual data after the response.
 349                         // We'll need to deal with that separately.
 350                         string extra_data;
 351                         if (status == RP_EXTRA_DATA) {
 352                                 char *ptr = static_cast<char *>(
 353                                         memmem(response.data(), response.size(), "\r\n\r\n", 4));
 354                                 assert(ptr != NULL);
 355                                 extra_data = string(ptr + 4, &response[0] + response.size());
 356                                 response.resize(ptr - response.data());
 357                         }
 358
 359                         if (!parse_response(response)) {
 360                                 state = CLOSING_SOCKET;
 361                                 continue;
 362                         }
 363
 364                         if (!extra_data.empty()) {
 365                                 process_data(&extra_data[0], extra_data.size());
 366                         }
 367
 368                         log(INFO, "[%s] Connected to '%s', receiving data.",
 369                                    url.c_str(), url.c_str());
 370                         state = RECEIVING_DATA;
 371                         break;
 372                 }
 373                 case RECEIVING_DATA: {
 374                         char buf[4096];
 375                         int ret;
 376
 377                         do {
 378                                 ret = read(sock, buf, sizeof(buf));
 379                         } while (ret == -1 && errno == EINTR);
 380
 381                         if (ret == -1) {
 382                                 log_perror("read");
 383                                 state = CLOSING_SOCKET;
 384                                 continue;
 385                         }
 386
 387                         if (ret == 0) {
 388                                 // This really shouldn't happen...
 389                                 log(ERROR, "[%s] Socket unexpectedly closed while reading data",
 390                                            url.c_str());
 391                                 state = CLOSING_SOCKET;
 392                                 continue;
 393                         }
 394
 395                         process_data(buf, ret);
 396                         break;
 397                 }
 398                 case CLOSING_SOCKET: {
 399                         close_socket();
 400                         state = NOT_CONNECTED;
 401                         break;
 402                 }
 403                 default:
 404                         assert(false);
 405                 }
 406
 407                 // If we are still in NOT_CONNECTED, either something went wrong,
 408                 // or the connection just got closed.
 409                 // The earlier steps have already given the error message, if any.
 410                 if (state == NOT_CONNECTED && !should_stop()) {
 411                         log(INFO, "[%s] Waiting 0.2 second and restarting...", url.c_str());
 412                         timespec timeout_ts;
 413                         timeout_ts.tv_sec = 0;
 414                         timeout_ts.tv_nsec = 200000000;
 415                         wait_for_wakeup(&timeout_ts);
 416                 }
 417         }
 418 }
 419
 420 void HTTPInput::process_data(char *ptr, size_t bytes)
 421 {
 422         pending_data.insert(pending_data.end(), ptr, ptr + bytes);
 423
 424         for ( ;; ) {
 425                 // If we don't have enough data (yet) for even the Metacube header, just return.
 426                 if (pending_data.size() < sizeof(metacube_block_header)) {
 427                         return;
 428                 }
 429
 430                 // Make sure we have the Metacube sync header at the start.
 431                 // We may need to skip over junk data (it _should_ not happen, though).
 432                 if (!has_metacube_header) {
 433                         char *ptr = static_cast<char *>(
 434                                 memmem(pending_data.data(), pending_data.size(),
 435                                        METACUBE_SYNC, strlen(METACUBE_SYNC)));
 436                         if (ptr == NULL) {
 437                                 // OK, so we didn't find the sync marker. We know then that
 438                                 // we do not have the _full_ marker in the buffer, but we
 439                                 // could have N-1 bytes. Drop everything before that,
 440                                 // and then give up.
 441                                 drop_pending_data(pending_data.size() - (strlen(METACUBE_SYNC) - 1));
 442                                 return;
 443                         } else {
 444                                 // Yay, we found the header. Drop everything (if anything) before it.
 445                                 drop_pending_data(ptr - pending_data.data());
 446                                 has_metacube_header = true;
 447
 448                                 // Re-check that we have the entire header; we could have dropped data.
 449                                 if (pending_data.size() < sizeof(metacube_block_header)) {
 450                                         return;
 451                                 }
 452                         }
 453                 }
 454
 455                 // Now it's safe to read the header.
 456                 metacube_block_header *hdr = reinterpret_cast<metacube_block_header *>(pending_data.data());
 457                 assert(memcmp(hdr->sync, METACUBE_SYNC, sizeof(hdr->sync)) == 0);
 458                 uint32_t size = ntohl(hdr->size);
 459                 uint32_t flags = ntohl(hdr->flags);
 460
 461                 if (size > 262144) {
 462                         log(WARNING, "[%s] Metacube block of %d bytes (flags=%x); corrupted header?",
 463                                 url.c_str(), size, flags);
 464                 }
 465
 466                 // See if we have the entire block. If not, wait for more data.
 467                 if (pending_data.size() < sizeof(metacube_block_header) + size) {
 468                         return;
 469                 }
 470
 471                 // Send this block on to the data.
 472                 char *inner_data = pending_data.data() + sizeof(metacube_block_header);
 473                 if (flags & METACUBE_FLAGS_HEADER) {
 474                         string header(inner_data, inner_data + size);
 475                         for (size_t i = 0; i < stream_indices.size(); ++i) {
 476                                 servers->set_header(stream_indices[i], http_header, header);
 477                         }
 478                 } else {
 479                         StreamStartSuitability suitable_for_stream_start;
 480                         if (flags & METACUBE_FLAGS_NOT_SUITABLE_FOR_STREAM_START) {
 481                                 suitable_for_stream_start = NOT_SUITABLE_FOR_STREAM_START;
 482                         } else {
 483                                 suitable_for_stream_start = SUITABLE_FOR_STREAM_START;
 484                         }
 485                         for (size_t i = 0; i < stream_indices.size(); ++i) {
 486                                 servers->add_data(stream_indices[i], inner_data, size, suitable_for_stream_start);
 487                         }
 488                 }
 489
 490                 // Consume the block. This isn't the most efficient way of dealing with things
 491                 // should we have many blocks, but these routines don't need to be too efficient
 492                 // anyway.
 493                 pending_data.erase(pending_data.begin(), pending_data.begin() + sizeof(metacube_block_header) + size);
 494                 has_metacube_header = false;
 495         }
 496 }
 497
 498 void HTTPInput::drop_pending_data(size_t num_bytes)
 499 {
 500         if (num_bytes == 0) {
 501                 return;
 502         }
 503         log(WARNING, "[%s] Dropping %lld junk bytes from stream, maybe it is not a Metacube stream?",
 504                 url.c_str(), (long long)num_bytes);
 505         assert(pending_data.size() >= num_bytes);
 506         pending_data.erase(pending_data.begin(), pending_data.begin() + num_bytes);
 507 }
 508