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 &stream_id, const string &url)
  31         : state(NOT_CONNECTED),
  32           stream_id(stream_id),
  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           stream_id(serialized.stream_id()),
  42           url(serialized.url()),
  43           request(serialized.request()),
  44           request_bytes_sent(serialized.request_bytes_sent()),
  45           response(serialized.response()),
  46           http_header(serialized.http_header()),
  47           has_metacube_header(serialized.has_metacube_header()),
  48           sock(serialized.sock())
  49 {
  50         pending_data.resize(serialized.pending_data().size());
  51         memcpy(&pending_data[0], serialized.pending_data().data(), serialized.pending_data().size());
  52
  53         string protocol;
  54         parse_url(url, &protocol, &host, &port, &path);  // Don't care if it fails.
  55 }
  56
  57 void HTTPInput::close_socket()
  58 {
  59         int ret;
  60         do {
  61                 ret = close(sock);
  62         } while (ret == -1 && errno == EINTR);
  63
  64         if (ret == -1) {
  65                 log_perror("close()");
  66         }
  67 }
  68
  69 InputProto HTTPInput::serialize() const
  70 {
  71         InputProto serialized;
  72         serialized.set_state(state);
  73         serialized.set_stream_id(stream_id);
  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                         stream_id.c_str(), host.c_str(), gai_strerror(err));
  92                 freeaddrinfo(ai);
  93                 return -1;
  94         }
  95
  96         // Connect to everything in turn until we have a socket.
  97         while (ai && !should_stop) {
  98                 int sock = socket(ai->ai_family, SOCK_STREAM, IPPROTO_TCP);
  99                 if (sock == -1) {
 100                         // Could be e.g. EPROTONOSUPPORT. The show must go on.
 101                         continue;
 102                 }
 103
 104                 do {
 105                         err = connect(sock, ai->ai_addr, ai->ai_addrlen);
 106                 } while (err == -1 && errno == EINTR);
 107
 108                 if (err != -1) {
 109                         freeaddrinfo(ai);
 110                         return sock;
 111                 }
 112
 113                 do {
 114                         err = close(sock);
 115                 } while (err == -1 && errno == EINTR);
 116
 117                 if (err == -1) {
 118                         log_perror("close");
 119                         // Can still continue.
 120                 }
 121
 122                 ai = ai->ai_next;
 123         }
 124
 125         // Give the last one as error.
 126         log(WARNING, "[%s] Connect to '%s' failed (%s)",
 127                 stream_id.c_str(), host.c_str(), strerror(errno));
 128         freeaddrinfo(ai);
 129         return -1;
 130 }
 131
 132 bool HTTPInput::parse_response(const std::string &request)
 133 {
 134         vector<string> lines = split_lines(response);
 135         if (lines.empty()) {
 136                 log(WARNING, "[%s] Empty HTTP response from input.", stream_id.c_str());
 137                 return false;
 138         }
 139
 140         vector<string> first_line_tokens = split_tokens(lines[0]);
 141         if (first_line_tokens.size() < 2) {
 142                 log(WARNING, "[%s] Malformed response line '%s' from input.",
 143                         stream_id.c_str(), lines[0].c_str());
 144                 return false;
 145         }
 146
 147         int response = atoi(first_line_tokens[1].c_str());
 148         if (response != 200) {
 149                 log(WARNING, "[%s] Non-200 response '%s' from input.",
 150                         stream_id.c_str(), lines[0].c_str());
 151                 return false;
 152         }
 153
 154         multimap<string, string> parameters;
 155         for (size_t i = 1; i < lines.size(); ++i) {
 156                 size_t split = lines[i].find(":");
 157                 if (split == string::npos) {
 158                         log(WARNING, "[%s] Ignoring malformed HTTP response line '%s'",
 159                                 stream_id.c_str(), lines[i].c_str());
 160                         continue;
 161                 }
 162
 163                 string key(lines[i].begin(), lines[i].begin() + split);
 164
 165                 // Skip any spaces after the colon.
 166                 do {
 167                         ++split;
 168                 } while (split < lines[i].size() && lines[i][split] == ' ');
 169
 170                 string value(lines[i].begin() + split, lines[i].end());
 171
 172                 // Remove “Content-encoding: metacube”.
 173                 // TODO: Make case-insensitive.
 174                 if (key == "Content-encoding" && value == "metacube") {
 175                         continue;
 176                 }
 177
 178                 parameters.insert(make_pair(key, value));
 179         }
 180
 181         // Change “Server: foo” to “Server: metacube/0.1 (reflecting: foo)”
 182         // TODO: Make case-insensitive.
 183         // XXX: Use a Via: instead?
 184         if (parameters.count("Server") == 0) {
 185                 parameters.insert(make_pair("Server", SERVER_IDENTIFICATION));
 186         } else {
 187                 for (multimap<string, string>::iterator it = parameters.begin();
 188                      it != parameters.end();
 189                      ++it) {
 190                         if (it->first != "Server") {
 191                                 continue;
 192                         }
 193                         it->second = SERVER_IDENTIFICATION " (reflecting: " + it->second + ")";
 194                 }
 195         }
 196
 197         // Construct the new HTTP header.
 198         http_header = "HTTP/1.0 200 OK\r\n";
 199         for (multimap<string, string>::iterator it = parameters.begin();
 200              it != parameters.end();
 201              ++it) {
 202                 http_header.append(it->first + ": " + it->second + "\r\n");
 203         }
 204         http_header.append("\r\n");
 205         servers->set_header(stream_id, http_header);
 206
 207         return true;
 208 }
 209
 210 void HTTPInput::do_work()
 211 {
 212         while (!should_stop) {
 213                 if (state == SENDING_REQUEST || state == RECEIVING_HEADER || state == RECEIVING_DATA) {
 214                         // Since we are non-blocking, we need to wait for the right state first.
 215                         // Wait up to 50 ms, then check should_stop.
 216                         pollfd pfd;
 217                         pfd.fd = sock;
 218                         pfd.events = (state == SENDING_REQUEST) ? POLLOUT : POLLIN;
 219                         pfd.events |= POLLRDHUP;
 220
 221                         int nfds = poll(&pfd, 1, 50);
 222                         if (nfds == 0 || (nfds == -1 && errno == EINTR)) {
 223                                 continue;
 224                         }
 225                         if (nfds == -1) {
 226                                 log_perror("poll");
 227                                 state = CLOSING_SOCKET;
 228                         }
 229                 }
 230
 231                 switch (state) {
 232                 case NOT_CONNECTED:
 233                         request.clear();
 234                         request_bytes_sent = 0;
 235                         response.clear();
 236                         pending_data.clear();
 237                         servers->set_header(stream_id, "");
 238
 239                         {
 240                                 string protocol;  // Thrown away.
 241                                 if (!parse_url(url, &protocol, &host, &port, &path)) {
 242                                         log(WARNING, "[%s] Failed to parse URL '%s'", stream_id.c_str(), url.c_str());
 243                                         break;
 244                                 }
 245                         }
 246
 247                         sock = lookup_and_connect(host, port);
 248                         if (sock != -1) {
 249                                 // Yay, successful connect. Try to set it as nonblocking.
 250                                 int one = 1;
 251                                 if (ioctl(sock, FIONBIO, &one) == -1) {
 252                                         log_perror("ioctl(FIONBIO)");
 253                                         state = CLOSING_SOCKET;
 254                                 } else {
 255                                         state = SENDING_REQUEST;
 256                                         request = "GET " + path + " HTTP/1.0\r\nUser-Agent: cubemap\r\n\r\n";
 257                                         request_bytes_sent = 0;
 258                                 }
 259                         }
 260                         break;
 261                 case SENDING_REQUEST: {
 262                         size_t to_send = request.size() - request_bytes_sent;
 263                         int ret;
 264
 265                         do {
 266                                 ret = write(sock, request.data() + request_bytes_sent, to_send);
 267                         } while (ret == -1 && errno == EINTR);
 268
 269                         if (ret == -1) {
 270                                 log_perror("write");
 271                                 state = CLOSING_SOCKET;
 272                                 continue;
 273                         }
 274
 275                         assert(ret >= 0);
 276                         request_bytes_sent += ret;
 277
 278                         if (request_bytes_sent == request.size()) {
 279                                 state = RECEIVING_HEADER;
 280                         }
 281                         break;
 282                 }
 283                 case RECEIVING_HEADER: {
 284                         char buf[4096];
 285                         int ret;
 286
 287                         do {
 288                                 ret = read(sock, buf, sizeof(buf));
 289                         } while (ret == -1 && errno == EINTR);
 290
 291                         if (ret == -1) {
 292                                 log_perror("read");
 293                                 state = CLOSING_SOCKET;
 294                                 continue;
 295                         }
 296
 297                         if (ret == 0) {
 298                                 // This really shouldn't happen...
 299                                 log(ERROR, "[%s] Socket unexpectedly closed while reading header",
 300                                            stream_id.c_str());
 301                                 state = CLOSING_SOCKET;
 302                                 continue;
 303                         }
 304
 305                         RequestParseStatus status = wait_for_double_newline(&response, buf, ret);
 306
 307                         if (status == RP_OUT_OF_SPACE) {
 308                                 log(WARNING, "[%s] Sever sent overlong HTTP response!", stream_id.c_str());
 309                                 state = CLOSING_SOCKET;
 310                                 continue;
 311                         } else if (status == RP_NOT_FINISHED_YET) {
 312                                 continue;
 313                         }
 314
 315                         // OK, so we're fine, but there might be some of the actual data after the response.
 316                         // We'll need to deal with that separately.
 317                         string extra_data;
 318                         if (status == RP_EXTRA_DATA) {
 319                                 char *ptr = static_cast<char *>(
 320                                         memmem(response.data(), response.size(), "\r\n\r\n", 4));
 321                                 assert(ptr != NULL);
 322                                 extra_data = string(ptr, &response[0] + response.size());
 323                                 response.resize(ptr - response.data());
 324                         }
 325
 326                         if (!parse_response(response)) {
 327                                 state = CLOSING_SOCKET;
 328                                 continue;
 329                         }
 330
 331                         if (!extra_data.empty()) {
 332                                 process_data(&extra_data[0], extra_data.size());
 333                         }
 334
 335                         log(INFO, "[%s] Connected to '%s', receiving data.",
 336                                    stream_id.c_str(), url.c_str());
 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                                 log_perror("read");
 350                                 state = CLOSING_SOCKET;
 351                                 continue;
 352                         }
 353
 354                         if (ret == 0) {
 355                                 // This really shouldn't happen...
 356                                 log(ERROR, "[%s] Socket unexpectedly closed while reading header",
 357                                            stream_id.c_str());
 358                                 state = CLOSING_SOCKET;
 359                                 continue;
 360                         }
 361
 362                         process_data(buf, ret);
 363                         break;
 364                 }
 365                 case CLOSING_SOCKET: {
 366                         int err;
 367                         do {
 368                                 err = close(sock);
 369                         } while (err == -1 && errno == EINTR);
 370
 371                         if (err == -1) {
 372                                 log_perror("close");
 373                         }
 374
 375                         state = NOT_CONNECTED;
 376                         break;
 377                 }
 378                 default:
 379                         assert(false);
 380                 }
 381
 382                 // If we are still in NOT_CONNECTED, either something went wrong,
 383                 // or the connection just got closed.
 384                 // The earlier steps have already given the error message, if any.
 385                 if (state == NOT_CONNECTED && !should_stop) {
 386                         log(INFO, "[%s] Waiting 0.2 second and restarting...", stream_id.c_str());
 387                         usleep(200000);
 388                 }
 389         }
 390 }
 391
 392 void HTTPInput::process_data(char *ptr, size_t bytes)
 393 {
 394         pending_data.insert(pending_data.end(), ptr, ptr + bytes);
 395
 396         for ( ;; ) {
 397                 // If we don't have enough data (yet) for even the Metacube header, just return.
 398                 if (pending_data.size() < sizeof(metacube_block_header)) {
 399                         return;
 400                 }
 401
 402                 // Make sure we have the Metacube sync header at the start.
 403                 // We may need to skip over junk data (it _should_ not happen, though).
 404                 if (!has_metacube_header) {
 405                         char *ptr = static_cast<char *>(
 406                                 memmem(pending_data.data(), pending_data.size(),
 407                                        METACUBE_SYNC, strlen(METACUBE_SYNC)));
 408                         if (ptr == NULL) {
 409                                 // OK, so we didn't find the sync marker. We know then that
 410                                 // we do not have the _full_ marker in the buffer, but we
 411                                 // could have N-1 bytes. Drop everything before that,
 412                                 // and then give up.
 413                                 drop_pending_data(pending_data.size() - (strlen(METACUBE_SYNC) - 1));
 414                                 return;
 415                         } else {
 416                                 // Yay, we found the header. Drop everything (if anything) before it.
 417                                 drop_pending_data(ptr - pending_data.data());
 418                                 has_metacube_header = true;
 419
 420                                 // Re-check that we have the entire header; we could have dropped data.
 421                                 if (pending_data.size() < sizeof(metacube_block_header)) {
 422                                         return;
 423                                 }
 424                         }
 425                 }
 426
 427                 // Now it's safe to read the header.
 428                 metacube_block_header *hdr = reinterpret_cast<metacube_block_header *>(pending_data.data());
 429                 assert(memcmp(hdr->sync, METACUBE_SYNC, sizeof(hdr->sync)) == 0);
 430                 uint32_t size = ntohl(hdr->size);
 431                 uint32_t flags = ntohl(hdr->flags);
 432
 433                 // See if we have the entire block. If not, wait for more data.
 434                 if (pending_data.size() < sizeof(metacube_block_header) + size) {
 435                         return;
 436                 }
 437
 438                 // Send this block on to the data.
 439                 char *inner_data = pending_data.data() + sizeof(metacube_block_header);
 440                 if (flags & METACUBE_FLAGS_HEADER) {
 441                         string header(inner_data, inner_data + size);
 442                         servers->set_header(stream_id, http_header + header);
 443                 } else {
 444                         servers->add_data(stream_id, inner_data, size);
 445                 }
 446
 447                 // Consume the block. This isn't the most efficient way of dealing with things
 448                 // should we have many blocks, but these routines don't need to be too efficient
 449                 // anyway.
 450                 pending_data.erase(pending_data.begin(), pending_data.begin() + sizeof(metacube_block_header) + size);
 451                 has_metacube_header = false;
 452         }
 453 }
 454
 455 void HTTPInput::drop_pending_data(size_t num_bytes)
 456 {
 457         if (num_bytes == 0) {
 458                 return;
 459         }
 460         log(WARNING, "[%s] Dropping %lld junk bytes from stream, maybe it is not a Metacube stream?",
 461                 stream_id.c_str(), (long long)num_bytes);
 462         pending_data.erase(pending_data.begin(), pending_data.begin() + num_bytes);
 463 }
 464