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         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                 do {
 107                         err = connect(sock, ai->ai_addr, ai->ai_addrlen);
 108                 } while (err == -1 && errno == EINTR);
 109
 110                 if (err != -1) {
 111                         freeaddrinfo(base_ai);
 112                         return sock;
 113                 }
 114
 115                 do {
 116                         err = close(sock);
 117                 } while (err == -1 && errno == EINTR);
 118
 119                 if (err == -1) {
 120                         log_perror("close");
 121                         // Can still continue.
 122                 }
 123
 124                 ai = ai->ai_next;
 125         }
 126
 127         // Give the last one as error.
 128         log(WARNING, "[%s] Connect to '%s' failed (%s)",
 129                 stream_id.c_str(), host.c_str(), strerror(errno));
 130         freeaddrinfo(base_ai);
 131         return -1;
 132 }
 133
 134 bool HTTPInput::parse_response(const std::string &request)
 135 {
 136         vector<string> lines = split_lines(response);
 137         if (lines.empty()) {
 138                 log(WARNING, "[%s] Empty HTTP response from input.", stream_id.c_str());
 139                 return false;
 140         }
 141
 142         vector<string> first_line_tokens = split_tokens(lines[0]);
 143         if (first_line_tokens.size() < 2) {
 144                 log(WARNING, "[%s] Malformed response line '%s' from input.",
 145                         stream_id.c_str(), lines[0].c_str());
 146                 return false;
 147         }
 148
 149         int response = atoi(first_line_tokens[1].c_str());
 150         if (response != 200) {
 151                 log(WARNING, "[%s] Non-200 response '%s' from input.",
 152                         stream_id.c_str(), lines[0].c_str());
 153                 return false;
 154         }
 155
 156         multimap<string, string> parameters;
 157         for (size_t i = 1; i < lines.size(); ++i) {
 158                 size_t split = lines[i].find(":");
 159                 if (split == string::npos) {
 160                         log(WARNING, "[%s] Ignoring malformed HTTP response line '%s'",
 161                                 stream_id.c_str(), lines[i].c_str());
 162                         continue;
 163                 }
 164
 165                 string key(lines[i].begin(), lines[i].begin() + split);
 166
 167                 // Skip any spaces after the colon.
 168                 do {
 169                         ++split;
 170                 } while (split < lines[i].size() && lines[i][split] == ' ');
 171
 172                 string value(lines[i].begin() + split, lines[i].end());
 173
 174                 // Remove “Content-encoding: metacube”.
 175                 // TODO: Make case-insensitive.
 176                 if (key == "Content-encoding" && value == "metacube") {
 177                         continue;
 178                 }
 179
 180                 parameters.insert(make_pair(key, value));
 181         }
 182
 183         // Change “Server: foo” to “Server: metacube/0.1 (reflecting: foo)”
 184         // TODO: Make case-insensitive.
 185         // XXX: Use a Via: instead?
 186         if (parameters.count("Server") == 0) {
 187                 parameters.insert(make_pair("Server", SERVER_IDENTIFICATION));
 188         } else {
 189                 for (multimap<string, string>::iterator it = parameters.begin();
 190                      it != parameters.end();
 191                      ++it) {
 192                         if (it->first != "Server") {
 193                                 continue;
 194                         }
 195                         it->second = SERVER_IDENTIFICATION " (reflecting: " + it->second + ")";
 196                 }
 197         }
 198
 199         // Construct the new HTTP header.
 200         http_header = "HTTP/1.0 200 OK\r\n";
 201         for (multimap<string, string>::iterator it = parameters.begin();
 202              it != parameters.end();
 203              ++it) {
 204                 http_header.append(it->first + ": " + it->second + "\r\n");
 205         }
 206         http_header.append("\r\n");
 207         servers->set_header(stream_id, http_header);
 208
 209         return true;
 210 }
 211
 212 void HTTPInput::do_work()
 213 {
 214         while (!should_stop) {
 215                 if (state == SENDING_REQUEST || state == RECEIVING_HEADER || state == RECEIVING_DATA) {
 216                         // Since we are non-blocking, we need to wait for the right state first.
 217                         // Wait up to 50 ms, then check should_stop.
 218                         pollfd pfd;
 219                         pfd.fd = sock;
 220                         pfd.events = (state == SENDING_REQUEST) ? POLLOUT : POLLIN;
 221                         pfd.events |= POLLRDHUP;
 222
 223                         int nfds = poll(&pfd, 1, 50);
 224                         if (nfds == 0 || (nfds == -1 && errno == EINTR)) {
 225                                 continue;
 226                         }
 227                         if (nfds == -1) {
 228                                 log_perror("poll");
 229                                 state = CLOSING_SOCKET;
 230                         }
 231                 }
 232
 233                 switch (state) {
 234                 case NOT_CONNECTED:
 235                         request.clear();
 236                         request_bytes_sent = 0;
 237                         response.clear();
 238                         pending_data.clear();
 239                         servers->set_header(stream_id, "");
 240
 241                         {
 242                                 string protocol;  // Thrown away.
 243                                 if (!parse_url(url, &protocol, &host, &port, &path)) {
 244                                         log(WARNING, "[%s] Failed to parse URL '%s'", stream_id.c_str(), url.c_str());
 245                                         break;
 246                                 }
 247                         }
 248
 249                         sock = lookup_and_connect(host, port);
 250                         if (sock != -1) {
 251                                 // Yay, successful connect. Try to set it as nonblocking.
 252                                 int one = 1;
 253                                 if (ioctl(sock, FIONBIO, &one) == -1) {
 254                                         log_perror("ioctl(FIONBIO)");
 255                                         state = CLOSING_SOCKET;
 256                                 } else {
 257                                         state = SENDING_REQUEST;
 258                                         request = "GET " + path + " HTTP/1.0\r\nUser-Agent: cubemap\r\n\r\n";
 259                                         request_bytes_sent = 0;
 260                                 }
 261                         }
 262                         break;
 263                 case SENDING_REQUEST: {
 264                         size_t to_send = request.size() - request_bytes_sent;
 265                         int ret;
 266
 267                         do {
 268                                 ret = write(sock, request.data() + request_bytes_sent, to_send);
 269                         } while (ret == -1 && errno == EINTR);
 270
 271                         if (ret == -1) {
 272                                 log_perror("write");
 273                                 state = CLOSING_SOCKET;
 274                                 continue;
 275                         }
 276
 277                         assert(ret >= 0);
 278                         request_bytes_sent += ret;
 279
 280                         if (request_bytes_sent == request.size()) {
 281                                 state = RECEIVING_HEADER;
 282                         }
 283                         break;
 284                 }
 285                 case RECEIVING_HEADER: {
 286                         char buf[4096];
 287                         int ret;
 288
 289                         do {
 290                                 ret = read(sock, buf, sizeof(buf));
 291                         } while (ret == -1 && errno == EINTR);
 292
 293                         if (ret == -1) {
 294                                 log_perror("read");
 295                                 state = CLOSING_SOCKET;
 296                                 continue;
 297                         }
 298
 299                         if (ret == 0) {
 300                                 // This really shouldn't happen...
 301                                 log(ERROR, "[%s] Socket unexpectedly closed while reading header",
 302                                            stream_id.c_str());
 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                                 log(WARNING, "[%s] Sever sent overlong HTTP response!", stream_id.c_str());
 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                         log(INFO, "[%s] Connected to '%s', receiving data.",
 338                                    stream_id.c_str(), url.c_str());
 339                         state = RECEIVING_DATA;
 340                         break;
 341                 }
 342                 case RECEIVING_DATA: {
 343                         char buf[4096];
 344                         int ret;
 345
 346                         do {
 347                                 ret = read(sock, buf, sizeof(buf));
 348                         } while (ret == -1 && errno == EINTR);
 349
 350                         if (ret == -1) {
 351                                 log_perror("read");
 352                                 state = CLOSING_SOCKET;
 353                                 continue;
 354                         }
 355
 356                         if (ret == 0) {
 357                                 // This really shouldn't happen...
 358                                 log(ERROR, "[%s] Socket unexpectedly closed while reading header",
 359                                            stream_id.c_str());
 360                                 state = CLOSING_SOCKET;
 361                                 continue;
 362                         }
 363
 364                         process_data(buf, ret);
 365                         break;
 366                 }
 367                 case CLOSING_SOCKET: {
 368                         int err;
 369                         do {
 370                                 err = close(sock);
 371                         } while (err == -1 && errno == EINTR);
 372
 373                         if (err == -1) {
 374                                 log_perror("close");
 375                         }
 376
 377                         state = NOT_CONNECTED;
 378                         break;
 379                 }
 380                 default:
 381                         assert(false);
 382                 }
 383
 384                 // If we are still in NOT_CONNECTED, either something went wrong,
 385                 // or the connection just got closed.
 386                 // The earlier steps have already given the error message, if any.
 387                 if (state == NOT_CONNECTED && !should_stop) {
 388                         log(INFO, "[%s] Waiting 0.2 second and restarting...", stream_id.c_str());
 389                         usleep(200000);
 390                 }
 391         }
 392 }
 393
 394 void HTTPInput::process_data(char *ptr, size_t bytes)
 395 {
 396         pending_data.insert(pending_data.end(), ptr, ptr + bytes);
 397
 398         for ( ;; ) {
 399                 // If we don't have enough data (yet) for even the Metacube header, just return.
 400                 if (pending_data.size() < sizeof(metacube_block_header)) {
 401                         return;
 402                 }
 403
 404                 // Make sure we have the Metacube sync header at the start.
 405                 // We may need to skip over junk data (it _should_ not happen, though).
 406                 if (!has_metacube_header) {
 407                         char *ptr = static_cast<char *>(
 408                                 memmem(pending_data.data(), pending_data.size(),
 409                                        METACUBE_SYNC, strlen(METACUBE_SYNC)));
 410                         if (ptr == NULL) {
 411                                 // OK, so we didn't find the sync marker. We know then that
 412                                 // we do not have the _full_ marker in the buffer, but we
 413                                 // could have N-1 bytes. Drop everything before that,
 414                                 // and then give up.
 415                                 drop_pending_data(pending_data.size() - (strlen(METACUBE_SYNC) - 1));
 416                                 return;
 417                         } else {
 418                                 // Yay, we found the header. Drop everything (if anything) before it.
 419                                 drop_pending_data(ptr - pending_data.data());
 420                                 has_metacube_header = true;
 421
 422                                 // Re-check that we have the entire header; we could have dropped data.
 423                                 if (pending_data.size() < sizeof(metacube_block_header)) {
 424                                         return;
 425                                 }
 426                         }
 427                 }
 428
 429                 // Now it's safe to read the header.
 430                 metacube_block_header *hdr = reinterpret_cast<metacube_block_header *>(pending_data.data());
 431                 assert(memcmp(hdr->sync, METACUBE_SYNC, sizeof(hdr->sync)) == 0);
 432                 uint32_t size = ntohl(hdr->size);
 433                 uint32_t flags = ntohl(hdr->flags);
 434
 435                 // See if we have the entire block. If not, wait for more data.
 436                 if (pending_data.size() < sizeof(metacube_block_header) + size) {
 437                         return;
 438                 }
 439
 440                 // Send this block on to the data.
 441                 char *inner_data = pending_data.data() + sizeof(metacube_block_header);
 442                 if (flags & METACUBE_FLAGS_HEADER) {
 443                         string header(inner_data, inner_data + size);
 444                         servers->set_header(stream_id, http_header + header);
 445                 } else {
 446                         servers->add_data(stream_id, inner_data, size);
 447                 }
 448
 449                 // Consume the block. This isn't the most efficient way of dealing with things
 450                 // should we have many blocks, but these routines don't need to be too efficient
 451                 // anyway.
 452                 pending_data.erase(pending_data.begin(), pending_data.begin() + sizeof(metacube_block_header) + size);
 453                 has_metacube_header = false;
 454         }
 455 }
 456
 457 void HTTPInput::drop_pending_data(size_t num_bytes)
 458 {
 459         if (num_bytes == 0) {
 460                 return;
 461         }
 462         log(WARNING, "[%s] Dropping %lld junk bytes from stream, maybe it is not a Metacube stream?",
 463                 stream_id.c_str(), (long long)num_bytes);
 464         pending_data.erase(pending_data.begin(), pending_data.begin() + num_bytes);
 465 }
 466