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 "metacube.h"
  20 #include "parse.h"
  21 #include "serverpool.h"
  22 #include "state.pb.h"
  23 #include "version.h"
  24
  25 using namespace std;
  26
  27 extern ServerPool *servers;
  28
  29 HTTPInput::HTTPInput(const string &stream_id, const string &url)
  30         : state(NOT_CONNECTED),
  31           stream_id(stream_id),
  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           stream_id(serialized.stream_id()),
  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
  56 void HTTPInput::close_socket()
  57 {
  58         int ret;
  59         do {
  60                 ret = close(sock);
  61         } while (ret == -1 && errno == EINTR);
  62
  63         if (ret == -1) {
  64                 perror("close()");
  65         }
  66 }
  67
  68 InputProto HTTPInput::serialize() const
  69 {
  70         InputProto serialized;
  71         serialized.set_state(state);
  72         serialized.set_stream_id(stream_id);
  73         serialized.set_url(url);
  74         serialized.set_request(request);
  75         serialized.set_request_bytes_sent(request_bytes_sent);
  76         serialized.set_response(response);
  77         serialized.set_http_header(http_header);
  78         serialized.set_pending_data(string(pending_data.begin(), pending_data.end()));
  79         serialized.set_has_metacube_header(has_metacube_header);
  80         serialized.set_sock(sock);
  81         return serialized;
  82 }
  83
  84 int HTTPInput::lookup_and_connect(const string &host, const string &port)
  85 {
  86         addrinfo *ai;
  87         int err = getaddrinfo(host.c_str(), port.c_str(), NULL, &ai);
  88         if (err == -1) {
  89                 fprintf(stderr, "WARNING: Lookup of '%s' failed (%s).\n",
  90                         host.c_str(), gai_strerror(err));
  91                 freeaddrinfo(ai);
  92                 return -1;
  93         }
  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(ai);
 109                         return sock;
 110                 }
 111
 112                 do {
 113                         err = close(sock);
 114                 } while (err == -1 && errno == EINTR);
 115
 116                 if (err == -1) {
 117                         perror("close");
 118                         // Can still continue.
 119                 }
 120
 121                 ai = ai->ai_next;
 122         }
 123
 124         // Give the last one as error.
 125         fprintf(stderr, "WARNING: Connect to '%s' failed (%s)\n",
 126                 host.c_str(), strerror(errno));
 127         freeaddrinfo(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                 fprintf(stderr, "WARNING: Empty HTTP response from input.\n");
 136                 return false;
 137         }
 138
 139         vector<string> first_line_tokens = split_tokens(lines[0]);
 140         if (first_line_tokens.size() < 2) {
 141                 fprintf(stderr, "WARNING: Malformed response line '%s' from input.\n",
 142                         lines[0].c_str());
 143                 return false;
 144         }
 145
 146         int response = atoi(first_line_tokens[1].c_str());
 147         if (response != 200) {
 148                 fprintf(stderr, "WARNING: Non-200 response '%s' from input.\n",
 149                         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                         fprintf(stderr, "WARNING: Ignoring malformed HTTP response line '%s'\n",
 158                                 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         servers->set_header(stream_id, http_header);
 205
 206         return true;
 207 }
 208
 209 void HTTPInput::do_work()
 210 {
 211         while (!should_stop) {
 212                 if (state == SENDING_REQUEST || state == RECEIVING_HEADER || state == RECEIVING_DATA) {
 213                         // Since we are non-blocking, we need to wait for the right state first.
 214                         // Wait up to 50 ms, then check should_stop.
 215                         pollfd pfd;
 216                         pfd.fd = sock;
 217                         pfd.events = (state == SENDING_REQUEST) ? POLLOUT : POLLIN;
 218                         pfd.events |= POLLRDHUP;
 219
 220                         int nfds = poll(&pfd, 1, 50);
 221                         if (nfds == 0 || (nfds == -1 && errno == EINTR)) {
 222                                 continue;
 223                         }
 224                         if (nfds == -1) {
 225                                 perror("poll");
 226                                 state = CLOSING_SOCKET;
 227                         }
 228                 }
 229
 230                 switch (state) {
 231                 case NOT_CONNECTED:
 232                         request.clear();
 233                         request_bytes_sent = 0;
 234                         response.clear();
 235                         pending_data.clear();
 236
 237                         {
 238                                 string protocol;  // Thrown away.
 239                                 if (!parse_url(url, &protocol, &host, &port, &path)) {
 240                                         fprintf(stderr, "Failed to parse URL '%s'\n", url.c_str());
 241                                         break;
 242                                 }
 243                         }
 244
 245                         sock = lookup_and_connect(host, port);
 246                         if (sock != -1) {
 247                                 // Yay, successful connect. Try to set it as nonblocking.
 248                                 int one = 1;
 249                                 if (ioctl(sock, FIONBIO, &one) == -1) {
 250                                         perror("ioctl(FIONBIO)");
 251                                         state = CLOSING_SOCKET;
 252                                 } else {
 253                                         state = SENDING_REQUEST;
 254                                         request = "GET " + path + " HTTP/1.0\r\nUser-Agent: cubemap\r\n\r\n";
 255                                         request_bytes_sent = 0;
 256                                 }
 257                         }
 258                         break;
 259                 case SENDING_REQUEST: {
 260                         size_t to_send = request.size() - request_bytes_sent;
 261                         int ret;
 262
 263                         do {
 264                                 ret = write(sock, request.data() + request_bytes_sent, to_send);
 265                         } while (ret == -1 && errno == EINTR);
 266
 267                         if (ret == -1) {
 268                                 perror("write");
 269                                 state = CLOSING_SOCKET;
 270                                 continue;
 271                         }
 272
 273                         assert(ret >= 0);
 274                         request_bytes_sent += ret;
 275
 276                         if (request_bytes_sent == request.size()) {
 277                                 state = RECEIVING_HEADER;
 278                         }
 279                         break;
 280                 }
 281                 case RECEIVING_HEADER: {
 282                         char buf[4096];
 283                         int ret;
 284
 285                         do {
 286                                 ret = read(sock, buf, sizeof(buf));
 287                         } while (ret == -1 && errno == EINTR);
 288
 289                         if (ret == -1) {
 290                                 perror("read");
 291                                 state = CLOSING_SOCKET;
 292                                 continue;
 293                         }
 294
 295                         if (ret == 0) {
 296                                 // This really shouldn't happen...
 297                                 fprintf(stderr, "Socket unexpectedly closed while reading header\n");
 298                                 state = CLOSING_SOCKET;
 299                                 continue;
 300                         }
 301
 302                         RequestParseStatus status = wait_for_double_newline(&response, buf, ret);
 303
 304                         if (status == RP_OUT_OF_SPACE) {
 305                                 fprintf(stderr, "WARNING: fd %d sent overlong response!\n", sock);
 306                                 state = CLOSING_SOCKET;
 307                                 continue;
 308                         } else if (status == RP_NOT_FINISHED_YET) {
 309                                 continue;
 310                         }
 311
 312                         // OK, so we're fine, but there might be some of the actual data after the response.
 313                         // We'll need to deal with that separately.
 314                         string extra_data;
 315                         if (status == RP_EXTRA_DATA) {
 316                                 char *ptr = static_cast<char *>(
 317                                         memmem(response.data(), response.size(), "\r\n\r\n", 4));
 318                                 assert(ptr != NULL);
 319                                 extra_data = string(ptr, &response[0] + response.size());
 320                                 response.resize(ptr - response.data());
 321                         }
 322
 323                         if (!parse_response(response)) {
 324                                 state = CLOSING_SOCKET;
 325                                 continue;
 326                         }
 327
 328                         if (!extra_data.empty()) {
 329                                 process_data(&extra_data[0], extra_data.size());
 330                         }
 331
 332                         state = RECEIVING_DATA;
 333                         break;
 334                 }
 335                 case RECEIVING_DATA: {
 336                         char buf[4096];
 337                         int ret;
 338
 339                         do {
 340                                 ret = read(sock, buf, sizeof(buf));
 341                         } while (ret == -1 && errno == EINTR);
 342
 343                         if (ret == -1) {
 344                                 perror("read");
 345                                 state = CLOSING_SOCKET;
 346                                 continue;
 347                         }
 348
 349                         if (ret == 0) {
 350                                 // This really shouldn't happen...
 351                                 fprintf(stderr, "Socket unexpectedly closed while reading header\n");
 352                                 state = CLOSING_SOCKET;
 353                                 continue;
 354                         }
 355
 356                         process_data(buf, ret);
 357                         break;
 358                 }
 359                 case CLOSING_SOCKET: {
 360                         int err;
 361                         do {
 362                                 err = close(sock);
 363                         } while (err == -1 && errno == EINTR);
 364
 365                         if (err == -1) {
 366                                 perror("close");
 367                         }
 368
 369                         state = NOT_CONNECTED;
 370                         break;
 371                 }
 372                 default:
 373                         assert(false);
 374                 }
 375
 376                 // If we are still in NOT_CONNECTED, either something went wrong,
 377                 // or the connection just got closed.
 378                 // The earlier steps have already given the error message, if any.
 379                 if (state == NOT_CONNECTED && !should_stop) {
 380                         fprintf(stderr, "Waiting 0.2 second and restarting...\n");
 381                         usleep(200000);
 382                 }
 383         }
 384 }
 385
 386 void HTTPInput::process_data(char *ptr, size_t bytes)
 387 {
 388         pending_data.insert(pending_data.end(), ptr, ptr + bytes);
 389
 390         for ( ;; ) {
 391                 // If we don't have enough data (yet) for even the Metacube header, just return.
 392                 if (pending_data.size() < sizeof(metacube_block_header)) {
 393                         return;
 394                 }
 395
 396                 // Make sure we have the Metacube sync header at the start.
 397                 // We may need to skip over junk data (it _should_ not happen, though).
 398                 if (!has_metacube_header) {
 399                         char *ptr = static_cast<char *>(
 400                                 memmem(pending_data.data(), pending_data.size(),
 401                                        METACUBE_SYNC, strlen(METACUBE_SYNC)));
 402                         if (ptr == NULL) {
 403                                 // OK, so we didn't find the sync marker. We know then that
 404                                 // we do not have the _full_ marker in the buffer, but we
 405                                 // could have N-1 bytes. Drop everything before that,
 406                                 // and then give up.
 407                                 drop_pending_data(pending_data.size() - (strlen(METACUBE_SYNC) - 1));
 408                                 return;
 409                         } else {
 410                                 // Yay, we found the header. Drop everything (if anything) before it.
 411                                 drop_pending_data(ptr - pending_data.data());
 412                                 has_metacube_header = true;
 413
 414                                 // Re-check that we have the entire header; we could have dropped data.
 415                                 if (pending_data.size() < sizeof(metacube_block_header)) {
 416                                         return;
 417                                 }
 418                         }
 419                 }
 420
 421                 // Now it's safe to read the header.
 422                 metacube_block_header *hdr = reinterpret_cast<metacube_block_header *>(pending_data.data());
 423                 assert(memcmp(hdr->sync, METACUBE_SYNC, sizeof(hdr->sync)) == 0);
 424                 uint32_t size = ntohl(hdr->size);
 425                 uint32_t flags = ntohl(hdr->flags);
 426
 427                 // See if we have the entire block. If not, wait for more data.
 428                 if (pending_data.size() < sizeof(metacube_block_header) + size) {
 429                         return;
 430                 }
 431
 432                 // Send this block on to the data.
 433                 char *inner_data = pending_data.data() + sizeof(metacube_block_header);
 434                 if (flags & METACUBE_FLAGS_HEADER) {
 435                         string header(inner_data, inner_data + size);
 436                         servers->set_header(stream_id, http_header + header);
 437                 } else {
 438                         servers->add_data(stream_id, inner_data, size);
 439                 }
 440
 441                 // Consume the block. This isn't the most efficient way of dealing with things
 442                 // should we have many blocks, but these routines don't need to be too efficient
 443                 // anyway.
 444                 pending_data.erase(pending_data.begin(), pending_data.begin() + sizeof(metacube_block_header) + size);
 445                 has_metacube_header = false;
 446         }
 447 }
 448
 449 void HTTPInput::drop_pending_data(size_t num_bytes)
 450 {
 451         if (num_bytes == 0) {
 452                 return;
 453         }
 454         fprintf(stderr, "Warning: Dropping %lld junk bytes from stream, maybe it is not a Metacube stream?\n",
 455                 (long long)num_bytes);
 456         pending_data.erase(pending_data.begin(), pending_data.begin() + num_bytes);
 457 }
 458