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
  55 void HTTPInput::close_socket()
  56 {
  57         int ret;
  58         do {
  59                 ret = close(sock);
  60         } while (ret == -1 && errno == EINTR);
  61
  62         if (ret == -1) {
  63                 log_perror("close()");
  64         }
  65 }
  66
  67 InputProto HTTPInput::serialize() const
  68 {
  69         InputProto serialized;
  70         serialized.set_state(state);
  71         serialized.set_url(url);
  72         serialized.set_request(request);
  73         serialized.set_request_bytes_sent(request_bytes_sent);
  74         serialized.set_response(response);
  75         serialized.set_http_header(http_header);
  76         serialized.set_pending_data(string(pending_data.begin(), pending_data.end()));
  77         serialized.set_has_metacube_header(has_metacube_header);
  78         serialized.set_sock(sock);
  79         return serialized;
  80 }
  81
  82 int HTTPInput::lookup_and_connect(const string &host, const string &port)
  83 {
  84         addrinfo *ai;
  85         int err = getaddrinfo(host.c_str(), port.c_str(), NULL, &ai);
  86         if (err == -1) {
  87                 log(WARNING, "[%s] Lookup of '%s' failed (%s).",
  88                         url.c_str(), host.c_str(), gai_strerror(err));
  89                 freeaddrinfo(ai);
  90                 return -1;
  91         }
  92
  93         addrinfo *base_ai = ai;
  94
  95         // Connect to everything in turn until we have a socket.
  96         while (ai && !should_stop) {
  97                 int sock = socket(ai->ai_family, SOCK_STREAM, IPPROTO_TCP);
  98                 if (sock == -1) {
  99                         // Could be e.g. EPROTONOSUPPORT. The show must go on.
 100                         continue;
 101                 }
 102
 103                 do {
 104                         err = connect(sock, ai->ai_addr, ai->ai_addrlen);
 105                 } while (err == -1 && errno == EINTR);
 106
 107                 if (err != -1) {
 108                         freeaddrinfo(base_ai);
 109                         return sock;
 110                 }
 111
 112                 do {
 113                         err = close(sock);
 114                 } while (err == -1 && errno == EINTR);
 115
 116                 if (err == -1) {
 117                         log_perror("close");
 118                         // Can still continue.
 119                 }
 120
 121                 ai = ai->ai_next;
 122         }
 123
 124         // Give the last one as error.
 125         log(WARNING, "[%s] Connect to '%s' failed (%s)",
 126                 url.c_str(), host.c_str(), strerror(errno));
 127         freeaddrinfo(base_ai);
 128         return -1;
 129 }
 130
 131 bool HTTPInput::parse_response(const std::string &request)
 132 {
 133         vector<string> lines = split_lines(response);
 134         if (lines.empty()) {
 135                 log(WARNING, "[%s] Empty HTTP response from input.", url.c_str());
 136                 return false;
 137         }
 138
 139         vector<string> first_line_tokens = split_tokens(lines[0]);
 140         if (first_line_tokens.size() < 2) {
 141                 log(WARNING, "[%s] Malformed response line '%s' from input.",
 142                         url.c_str(), lines[0].c_str());
 143                 return false;
 144         }
 145
 146         int response = atoi(first_line_tokens[1].c_str());
 147         if (response != 200) {
 148                 log(WARNING, "[%s] Non-200 response '%s' from input.",
 149                         url.c_str(), lines[0].c_str());
 150                 return false;
 151         }
 152
 153         multimap<string, string> parameters;
 154         for (size_t i = 1; i < lines.size(); ++i) {
 155                 size_t split = lines[i].find(":");
 156                 if (split == string::npos) {
 157                         log(WARNING, "[%s] Ignoring malformed HTTP response line '%s'",
 158                                 url.c_str(), lines[i].c_str());
 159                         continue;
 160                 }
 161
 162                 string key(lines[i].begin(), lines[i].begin() + split);
 163
 164                 // Skip any spaces after the colon.
 165                 do {
 166                         ++split;
 167                 } while (split < lines[i].size() && lines[i][split] == ' ');
 168
 169                 string value(lines[i].begin() + split, lines[i].end());
 170
 171                 // Remove “Content-encoding: metacube”.
 172                 // TODO: Make case-insensitive.
 173                 if (key == "Content-encoding" && value == "metacube") {
 174                         continue;
 175                 }
 176
 177                 parameters.insert(make_pair(key, value));
 178         }
 179
 180         // Change “Server: foo” to “Server: metacube/0.1 (reflecting: foo)”
 181         // TODO: Make case-insensitive.
 182         // XXX: Use a Via: instead?
 183         if (parameters.count("Server") == 0) {
 184                 parameters.insert(make_pair("Server", SERVER_IDENTIFICATION));
 185         } else {
 186                 for (multimap<string, string>::iterator it = parameters.begin();
 187                      it != parameters.end();
 188                      ++it) {
 189                         if (it->first != "Server") {
 190                                 continue;
 191                         }
 192                         it->second = SERVER_IDENTIFICATION " (reflecting: " + it->second + ")";
 193                 }
 194         }
 195
 196         // Construct the new HTTP header.
 197         http_header = "HTTP/1.0 200 OK\r\n";
 198         for (multimap<string, string>::iterator it = parameters.begin();
 199              it != parameters.end();
 200              ++it) {
 201                 http_header.append(it->first + ": " + it->second + "\r\n");
 202         }
 203         http_header.append("\r\n");
 204
 205         for (size_t i = 0; i < stream_ids.size(); ++i) {
 206                 servers->set_header(stream_ids[i], http_header);
 207         }
 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                         for (size_t i = 0; i < stream_ids.size(); ++i) {
 240                                 servers->set_header(stream_ids[i], "");
 241                         }
 242
 243                         {
 244                                 string protocol;  // Thrown away.
 245                                 if (!parse_url(url, &protocol, &host, &port, &path)) {
 246                                         log(WARNING, "[%s] Failed to parse URL '%s'", url.c_str(), url.c_str());
 247                                         break;
 248                                 }
 249                         }
 250
 251                         sock = lookup_and_connect(host, port);
 252                         if (sock != -1) {
 253                                 // Yay, successful connect. Try to set it as nonblocking.
 254                                 int one = 1;
 255                                 if (ioctl(sock, FIONBIO, &one) == -1) {
 256                                         log_perror("ioctl(FIONBIO)");
 257                                         state = CLOSING_SOCKET;
 258                                 } else {
 259                                         state = SENDING_REQUEST;
 260                                         request = "GET " + path + " HTTP/1.0\r\nUser-Agent: cubemap\r\n\r\n";
 261                                         request_bytes_sent = 0;
 262                                 }
 263                         }
 264                         break;
 265                 case SENDING_REQUEST: {
 266                         size_t to_send = request.size() - request_bytes_sent;
 267                         int ret;
 268
 269                         do {
 270                                 ret = write(sock, request.data() + request_bytes_sent, to_send);
 271                         } while (ret == -1 && errno == EINTR);
 272
 273                         if (ret == -1) {
 274                                 log_perror("write");
 275                                 state = CLOSING_SOCKET;
 276                                 continue;
 277                         }
 278
 279                         assert(ret >= 0);
 280                         request_bytes_sent += ret;
 281
 282                         if (request_bytes_sent == request.size()) {
 283                                 state = RECEIVING_HEADER;
 284                         }
 285                         break;
 286                 }
 287                 case RECEIVING_HEADER: {
 288                         char buf[4096];
 289                         int ret;
 290
 291                         do {
 292                                 ret = read(sock, buf, sizeof(buf));
 293                         } while (ret == -1 && errno == EINTR);
 294
 295                         if (ret == -1) {
 296                                 log_perror("read");
 297                                 state = CLOSING_SOCKET;
 298                                 continue;
 299                         }
 300
 301                         if (ret == 0) {
 302                                 // This really shouldn't happen...
 303                                 log(ERROR, "[%s] Socket unexpectedly closed while reading header",
 304                                            url.c_str());
 305                                 state = CLOSING_SOCKET;
 306                                 continue;
 307                         }
 308
 309                         RequestParseStatus status = wait_for_double_newline(&response, buf, ret);
 310
 311                         if (status == RP_OUT_OF_SPACE) {
 312                                 log(WARNING, "[%s] Sever sent overlong HTTP response!", url.c_str());
 313                                 state = CLOSING_SOCKET;
 314                                 continue;
 315                         } else if (status == RP_NOT_FINISHED_YET) {
 316                                 continue;
 317                         }
 318
 319                         // OK, so we're fine, but there might be some of the actual data after the response.
 320                         // We'll need to deal with that separately.
 321                         string extra_data;
 322                         if (status == RP_EXTRA_DATA) {
 323                                 char *ptr = static_cast<char *>(
 324                                         memmem(response.data(), response.size(), "\r\n\r\n", 4));
 325                                 assert(ptr != NULL);
 326                                 extra_data = string(ptr, &response[0] + response.size());
 327                                 response.resize(ptr - response.data());
 328                         }
 329
 330                         if (!parse_response(response)) {
 331                                 state = CLOSING_SOCKET;
 332                                 continue;
 333                         }
 334
 335                         if (!extra_data.empty()) {
 336                                 process_data(&extra_data[0], extra_data.size());
 337                         }
 338
 339                         log(INFO, "[%s] Connected to '%s', receiving data.",
 340                                    url.c_str(), url.c_str());
 341                         state = RECEIVING_DATA;
 342                         break;
 343                 }
 344                 case RECEIVING_DATA: {
 345                         char buf[4096];
 346                         int ret;
 347
 348                         do {
 349                                 ret = read(sock, buf, sizeof(buf));
 350                         } while (ret == -1 && errno == EINTR);
 351
 352                         if (ret == -1) {
 353                                 log_perror("read");
 354                                 state = CLOSING_SOCKET;
 355                                 continue;
 356                         }
 357
 358                         if (ret == 0) {
 359                                 // This really shouldn't happen...
 360                                 log(ERROR, "[%s] Socket unexpectedly closed while reading header",
 361                                            url.c_str());
 362                                 state = CLOSING_SOCKET;
 363                                 continue;
 364                         }
 365
 366                         process_data(buf, ret);
 367                         break;
 368                 }
 369                 case CLOSING_SOCKET: {
 370                         int err;
 371                         do {
 372                                 err = close(sock);
 373                         } while (err == -1 && errno == EINTR);
 374
 375                         if (err == -1) {
 376                                 log_perror("close");
 377                         }
 378
 379                         state = NOT_CONNECTED;
 380                         break;
 381                 }
 382                 default:
 383                         assert(false);
 384                 }
 385
 386                 // If we are still in NOT_CONNECTED, either something went wrong,
 387                 // or the connection just got closed.
 388                 // The earlier steps have already given the error message, if any.
 389                 if (state == NOT_CONNECTED && !should_stop) {
 390                         log(INFO, "[%s] Waiting 0.2 second and restarting...", url.c_str());
 391                         usleep(200000);
 392                 }
 393         }
 394 }
 395
 396 void HTTPInput::process_data(char *ptr, size_t bytes)
 397 {
 398         pending_data.insert(pending_data.end(), ptr, ptr + bytes);
 399
 400         for ( ;; ) {
 401                 // If we don't have enough data (yet) for even the Metacube header, just return.
 402                 if (pending_data.size() < sizeof(metacube_block_header)) {
 403                         return;
 404                 }
 405
 406                 // Make sure we have the Metacube sync header at the start.
 407                 // We may need to skip over junk data (it _should_ not happen, though).
 408                 if (!has_metacube_header) {
 409                         char *ptr = static_cast<char *>(
 410                                 memmem(pending_data.data(), pending_data.size(),
 411                                        METACUBE_SYNC, strlen(METACUBE_SYNC)));
 412                         if (ptr == NULL) {
 413                                 // OK, so we didn't find the sync marker. We know then that
 414                                 // we do not have the _full_ marker in the buffer, but we
 415                                 // could have N-1 bytes. Drop everything before that,
 416                                 // and then give up.
 417                                 drop_pending_data(pending_data.size() - (strlen(METACUBE_SYNC) - 1));
 418                                 return;
 419                         } else {
 420                                 // Yay, we found the header. Drop everything (if anything) before it.
 421                                 drop_pending_data(ptr - pending_data.data());
 422                                 has_metacube_header = true;
 423
 424                                 // Re-check that we have the entire header; we could have dropped data.
 425                                 if (pending_data.size() < sizeof(metacube_block_header)) {
 426                                         return;
 427                                 }
 428                         }
 429                 }
 430
 431                 // Now it's safe to read the header.
 432                 metacube_block_header *hdr = reinterpret_cast<metacube_block_header *>(pending_data.data());
 433                 assert(memcmp(hdr->sync, METACUBE_SYNC, sizeof(hdr->sync)) == 0);
 434                 uint32_t size = ntohl(hdr->size);
 435                 uint32_t flags = ntohl(hdr->flags);
 436
 437                 // See if we have the entire block. If not, wait for more data.
 438                 if (pending_data.size() < sizeof(metacube_block_header) + size) {
 439                         return;
 440                 }
 441
 442                 // Send this block on to the data.
 443                 char *inner_data = pending_data.data() + sizeof(metacube_block_header);
 444                 if (flags & METACUBE_FLAGS_HEADER) {
 445                         string header(inner_data, inner_data + size);
 446                         for (size_t i = 0; i < stream_ids.size(); ++i) {
 447                                 servers->set_header(stream_ids[i], http_header + header);
 448                         }
 449                 } else {
 450                         for (size_t i = 0; i < stream_ids.size(); ++i) {
 451                                 servers->add_data(stream_ids[i], inner_data, size);
 452                         }
 453                 }
 454
 455                 // Consume the block. This isn't the most efficient way of dealing with things
 456                 // should we have many blocks, but these routines don't need to be too efficient
 457                 // anyway.
 458                 pending_data.erase(pending_data.begin(), pending_data.begin() + sizeof(metacube_block_header) + size);
 459                 has_metacube_header = false;
 460         }
 461 }
 462
 463 void HTTPInput::drop_pending_data(size_t num_bytes)
 464 {
 465         if (num_bytes == 0) {
 466                 return;
 467         }
 468         log(WARNING, "[%s] Dropping %lld junk bytes from stream, maybe it is not a Metacube stream?",
 469                 url.c_str(), (long long)num_bytes);
 470         pending_data.erase(pending_data.begin(), pending_data.begin() + num_bytes);
 471 }
 472