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