git.sesse.net Git - cubemap/blob - httpinput.cpp

   1 #include <stdio.h>
   2 #include <string.h>
   3 #include <stdint.h>
   4 #include <assert.h>
   5 #include <arpa/inet.h>
   6 #include <sys/socket.h>
   7 #include <pthread.h>
   8 #include <sys/types.h>
   9 #include <sys/ioctl.h>
  10 #include <sys/types.h>
  11 #include <sys/socket.h>
  12 #include <netdb.h>
  13 #include <poll.h>
  14 #include <signal.h>
  15 #include <errno.h>
  16 #include <vector>
  17 #include <string>
  18 #include <map>
  19
  20 #include "metacube.h"
  21 #include "mutexlock.h"
  22 #include "httpinput.h"
  23 #include "server.h"
  24 #include "serverpool.h"
  25 #include "parse.h"
  26 #include "version.h"
  27 #include "state.pb.h"
  28
  29 using namespace std;
  30
  31 extern ServerPool *servers;
  32
  33 HTTPInput::HTTPInput(const string &stream_id, const string &url)
  34         : state(NOT_CONNECTED),
  35           stream_id(stream_id),
  36           url(url),
  37           has_metacube_header(false),
  38           sock(-1)
  39 {
  40 }
  41
  42 HTTPInput::HTTPInput(const InputProto &serialized)
  43         : state(State(serialized.state())),
  44           stream_id(serialized.stream_id()),
  45           url(serialized.url()),
  46           request(serialized.request()),
  47           request_bytes_sent(serialized.request_bytes_sent()),
  48           response(serialized.response()),
  49           http_header(serialized.http_header()),
  50           has_metacube_header(serialized.has_metacube_header()),
  51           sock(serialized.sock())
  52 {
  53         pending_data.resize(serialized.pending_data().size());
  54         memcpy(&pending_data[0], serialized.pending_data().data(), serialized.pending_data().size());
  55
  56         string protocol;
  57         parse_url(url, &protocol, &host, &port, &path);  // Don't care if it fails.
  58 }
  59
  60 void HTTPInput::close_socket()
  61 {
  62         int ret;
  63         do {
  64                 ret = close(sock);
  65         } while (ret == -1 && errno == EINTR);
  66
  67         if (ret == -1) {
  68                 perror("close()");
  69         }
  70 }
  71
  72 InputProto HTTPInput::serialize() const
  73 {
  74         InputProto serialized;
  75         serialized.set_state(state);
  76         serialized.set_stream_id(stream_id);
  77         serialized.set_url(url);
  78         serialized.set_request(request);
  79         serialized.set_request_bytes_sent(request_bytes_sent);
  80         serialized.set_response(response);
  81         serialized.set_http_header(http_header);
  82         serialized.set_pending_data(string(pending_data.begin(), pending_data.end()));
  83         serialized.set_has_metacube_header(has_metacube_header);
  84         serialized.set_sock(sock);
  85         return serialized;
  86 }
  87
  88 int HTTPInput::lookup_and_connect(const string &host, const string &port)
  89 {
  90         addrinfo *ai;
  91         int err = getaddrinfo(host.c_str(), port.c_str(), NULL, &ai);
  92         if (err == -1) {
  93                 fprintf(stderr, "WARNING: Lookup of '%s' failed (%s).\n",
  94                         host.c_str(), gai_strerror(err));
  95                 freeaddrinfo(ai);
  96                 return -1;
  97         }
  98
  99         // Connect to everything in turn until we have a socket.
 100         while (ai && !should_stop) {
 101                 int sock = socket(ai->ai_family, SOCK_STREAM, IPPROTO_TCP);
 102                 if (sock == -1) {
 103                         // Could be e.g. EPROTONOSUPPORT. The show must go on.
 104                         continue;
 105                 }
 106
 107                 do {
 108                         err = connect(sock, ai->ai_addr, ai->ai_addrlen);
 109                 } while (err == -1 && errno == EINTR);
 110
 111                 if (err != -1) {
 112                         freeaddrinfo(ai);
 113                         return sock;
 114                 }
 115
 116                 ai = ai->ai_next;
 117         }
 118
 119         // Give the last one as error.
 120         fprintf(stderr, "WARNING: Connect to '%s' failed (%s)\n",
 121                 host.c_str(), strerror(errno));
 122         freeaddrinfo(ai);
 123         return -1;
 124 }
 125
 126 bool HTTPInput::parse_response(const std::string &request)
 127 {
 128         vector<string> lines = split_lines(response);
 129         if (lines.empty()) {
 130                 fprintf(stderr, "WARNING: Empty HTTP response from input.\n");
 131                 return false;
 132         }
 133
 134         vector<string> first_line_tokens = split_tokens(lines[0]);
 135         if (first_line_tokens.size() < 2) {
 136                 fprintf(stderr, "WARNING: Malformed response line '%s' from input.\n",
 137                         lines[0].c_str());
 138                 return false;
 139         }
 140
 141         int response = atoi(first_line_tokens[1].c_str());
 142         if (response != 200) {
 143                 fprintf(stderr, "WARNING: Non-200 response '%s' from input.\n",
 144                         lines[0].c_str());
 145                 return false;
 146         }
 147
 148         multimap<string, string> parameters;
 149         for (size_t i = 1; i < lines.size(); ++i) {
 150                 size_t split = lines[i].find(":");
 151                 if (split == string::npos) {
 152                         fprintf(stderr, "WARNING: Ignoring malformed HTTP response line '%s'\n",
 153                                 lines[i].c_str());
 154                         continue;
 155                 }
 156
 157                 string key(lines[i].begin(), lines[i].begin() + split);
 158
 159                 // Skip any spaces after the colon.
 160                 do {
 161                         ++split;
 162                 } while (split < lines[i].size() && lines[i][split] == ' ');
 163
 164                 string value(lines[i].begin() + split, lines[i].end());
 165
 166                 // Remove “Content-encoding: metacube”.
 167                 // TODO: Make case-insensitive.
 168                 if (key == "Content-encoding" && value == "metacube") {
 169                         continue;
 170                 }
 171
 172                 parameters.insert(make_pair(key, value));
 173         }
 174
 175         // Change “Server: foo” to “Server: metacube/0.1 (reflecting: foo)”
 176         // TODO: Make case-insensitive.
 177         // XXX: Use a Via: instead?
 178         if (parameters.count("Server") == 0) {
 179                 parameters.insert(make_pair("Server", SERVER_IDENTIFICATION));
 180         } else {
 181                 for (multimap<string, string>::iterator it = parameters.begin();
 182                      it != parameters.end();
 183                      ++it) {
 184                         if (it->first != "Server") {
 185                                 continue;
 186                         }
 187                         it->second = SERVER_IDENTIFICATION " (reflecting: " + it->second + ")";
 188                 }
 189         }
 190
 191         // Construct the new HTTP header.
 192         http_header = "HTTP/1.0 200 OK\r\n";
 193         for (multimap<string, string>::iterator it = parameters.begin();
 194              it != parameters.end();
 195              ++it) {
 196                 http_header.append(it->first + ": " + it->second + "\r\n");
 197         }
 198         http_header.append("\r\n");
 199         servers->set_header(stream_id, http_header);
 200
 201         return true;
 202 }
 203
 204 void HTTPInput::do_work()
 205 {
 206         while (!should_stop) {
 207                 if (state == SENDING_REQUEST || state == RECEIVING_HEADER || state == RECEIVING_DATA) {
 208                         // Since we are non-blocking, we need to wait for the right state first.
 209                         // Wait up to 50 ms, then check should_stop.
 210                         pollfd pfd;
 211                         pfd.fd = sock;
 212                         pfd.events = (state == SENDING_REQUEST) ? POLLOUT : POLLIN;
 213                         pfd.events |= POLLRDHUP;
 214
 215                         int nfds = poll(&pfd, 1, 50);
 216                         if (nfds == 0 || (nfds == -1 && errno == EINTR)) {
 217                                 continue;
 218                         }
 219                         if (nfds == -1) {
 220                                 perror("poll");
 221                                 state = CLOSING_SOCKET;
 222                         }
 223                 }
 224
 225                 switch (state) {
 226                 case NOT_CONNECTED:
 227                         request.clear();
 228                         request_bytes_sent = 0;
 229                         response.clear();
 230                         pending_data.clear();
 231
 232                         {
 233                                 string protocol;  // Thrown away.
 234                                 if (!parse_url(url, &protocol, &host, &port, &path)) {
 235                                         fprintf(stderr, "Failed to parse URL '%s'\n", url.c_str());
 236                                         break;
 237                                 }
 238                         }
 239
 240                         sock = lookup_and_connect(host, port);
 241                         if (sock != -1) {
 242                                 // Yay, successful connect. Try to set it as nonblocking.
 243                                 int one = 1;
 244                                 if (ioctl(sock, FIONBIO, &one) == -1) {
 245                                         perror("ioctl(FIONBIO)");
 246                                         state = CLOSING_SOCKET;
 247                                 } else {
 248                                         state = SENDING_REQUEST;
 249                                         request = "GET " + path + " HTTP/1.0\r\nUser-Agent: cubemap\r\n\r\n";
 250                                         request_bytes_sent = 0;
 251                                 }
 252                         }
 253                         break;
 254                 case SENDING_REQUEST: {
 255                         size_t to_send = request.size() - request_bytes_sent;
 256                         int ret;
 257
 258                         do {
 259                                 ret = write(sock, request.data() + request_bytes_sent, to_send);
 260                         } while (ret == -1 && errno == EINTR);
 261
 262                         if (ret == -1) {
 263                                 perror("write");
 264                                 state = CLOSING_SOCKET;
 265                                 continue;
 266                         }
 267
 268                         assert(ret >= 0);
 269                         request_bytes_sent += ret;
 270
 271                         if (request_bytes_sent == request.size()) {
 272                                 state = RECEIVING_HEADER;
 273                         }
 274                         break;
 275                 }
 276                 case RECEIVING_HEADER: {
 277                         char buf[4096];
 278                         int ret;
 279
 280                         do {
 281                                 ret = read(sock, buf, sizeof(buf));
 282                         } while (ret == -1 && errno == EINTR);
 283
 284                         if (ret == -1) {
 285                                 perror("read");
 286                                 state = CLOSING_SOCKET;
 287                                 continue;
 288                         }
 289
 290                         if (ret == 0) {
 291                                 // This really shouldn't happen...
 292                                 fprintf(stderr, "Socket unexpectedly closed while reading header\n");
 293                                 state = CLOSING_SOCKET;
 294                                 continue;
 295                         }
 296
 297                         RequestParseStatus status = wait_for_double_newline(&response, buf, ret);
 298
 299                         if (status == RP_OUT_OF_SPACE) {
 300                                 fprintf(stderr, "WARNING: fd %d sent overlong response!\n", sock);
 301                                 state = CLOSING_SOCKET;
 302                                 continue;
 303                         } else if (status == RP_NOT_FINISHED_YET) {
 304                                 continue;
 305                         }
 306
 307                         // OK, so we're fine, but there might be some of the actual data after the response.
 308                         // We'll need to deal with that separately.
 309                         string extra_data;
 310                         if (status == RP_EXTRA_DATA) {
 311                                 char *ptr = static_cast<char *>(
 312                                         memmem(response.data(), response.size(), "\r\n\r\n", 4));
 313                                 assert(ptr != NULL);
 314                                 extra_data = string(ptr, &response[0] + response.size());
 315                                 response.resize(ptr - response.data());
 316                         }
 317
 318                         if (!parse_response(response)) {
 319                                 state = CLOSING_SOCKET;
 320                                 continue;
 321                         }
 322
 323                         if (!extra_data.empty()) {
 324                                 process_data(&extra_data[0], extra_data.size());
 325                         }
 326
 327                         state = RECEIVING_DATA;
 328                         break;
 329                 }
 330                 case RECEIVING_DATA: {
 331                         char buf[4096];
 332                         int ret;
 333
 334                         do {
 335                                 ret = read(sock, buf, sizeof(buf));
 336                         } while (ret == -1 && errno == EINTR);
 337
 338                         if (ret == -1) {
 339                                 perror("read");
 340                                 state = CLOSING_SOCKET;
 341                                 continue;
 342                         }
 343
 344                         if (ret == 0) {
 345                                 // This really shouldn't happen...
 346                                 fprintf(stderr, "Socket unexpectedly closed while reading header\n");
 347                                 state = CLOSING_SOCKET;
 348                                 continue;
 349                         }
 350
 351                         process_data(buf, ret);
 352                         break;
 353                 }
 354                 case CLOSING_SOCKET: {
 355                         int err;
 356                         do {
 357                                 err = close(sock);
 358                         } while (err == -1 && errno == EINTR);
 359
 360                         if (err == -1) {
 361                                 perror("close");
 362                         }
 363
 364                         state = NOT_CONNECTED;
 365                         break;
 366                 }
 367                 default:
 368                         assert(false);
 369                 }
 370
 371                 // If we are still in NOT_CONNECTED, either something went wrong,
 372                 // or the connection just got closed.
 373                 // The earlier steps have already given the error message, if any.
 374                 if (state == NOT_CONNECTED && !should_stop) {
 375                         fprintf(stderr, "Waiting 0.2 second and restarting...\n");
 376                         usleep(200000);
 377                 }
 378         }
 379 }
 380
 381 void HTTPInput::process_data(char *ptr, size_t bytes)
 382 {
 383         pending_data.insert(pending_data.end(), ptr, ptr + bytes);
 384
 385         for ( ;; ) {
 386                 // If we don't have enough data (yet) for even the Metacube header, just return.
 387                 if (pending_data.size() < sizeof(metacube_block_header)) {
 388                         return;
 389                 }
 390
 391                 // Make sure we have the Metacube sync header at the start.
 392                 // We may need to skip over junk data (it _should_ not happen, though).
 393                 if (!has_metacube_header) {
 394                         char *ptr = static_cast<char *>(
 395                                 memmem(pending_data.data(), pending_data.size(),
 396                                        METACUBE_SYNC, strlen(METACUBE_SYNC)));
 397                         if (ptr == NULL) {
 398                                 // OK, so we didn't find the sync marker. We know then that
 399                                 // we do not have the _full_ marker in the buffer, but we
 400                                 // could have N-1 bytes. Drop everything before that,
 401                                 // and then give up.
 402                                 drop_pending_data(pending_data.size() - (strlen(METACUBE_SYNC) - 1));
 403                                 return;
 404                         } else {
 405                                 // Yay, we found the header. Drop everything (if anything) before it.
 406                                 drop_pending_data(ptr - pending_data.data());
 407                                 has_metacube_header = true;
 408
 409                                 // Re-check that we have the entire header; we could have dropped data.
 410                                 if (pending_data.size() < sizeof(metacube_block_header)) {
 411                                         return;
 412                                 }
 413                         }
 414                 }
 415
 416                 // Now it's safe to read the header.
 417                 metacube_block_header *hdr = reinterpret_cast<metacube_block_header *>(pending_data.data());
 418                 assert(memcmp(hdr->sync, METACUBE_SYNC, sizeof(hdr->sync)) == 0);
 419                 uint32_t size = ntohl(hdr->size);
 420                 uint32_t flags = ntohl(hdr->flags);
 421
 422                 // See if we have the entire block. If not, wait for more data.
 423                 if (pending_data.size() < sizeof(metacube_block_header) + size) {
 424                         return;
 425                 }
 426
 427                 // Send this block on to the data.
 428                 char *inner_data = pending_data.data() + sizeof(metacube_block_header);
 429                 if (flags & METACUBE_FLAGS_HEADER) {
 430                         string header(inner_data, inner_data + size);
 431                         servers->set_header(stream_id, http_header + header);
 432                 } else {
 433                         servers->add_data(stream_id, inner_data, size);
 434                 }
 435
 436                 // Consume the block. This isn't the most efficient way of dealing with things
 437                 // should we have many blocks, but these routines don't need to be too efficient
 438                 // anyway.
 439                 pending_data.erase(pending_data.begin(), pending_data.begin() + sizeof(metacube_block_header) + size);
 440                 has_metacube_header = false;
 441         }
 442 }
 443
 444 void HTTPInput::drop_pending_data(size_t num_bytes)
 445 {
 446         if (num_bytes == 0) {
 447                 return;
 448         }
 449         fprintf(stderr, "Warning: Dropping %lld junk bytes from stream, maybe it is not a Metacube stream?\n",
 450                 (long long)num_bytes);
 451         pending_data.erase(pending_data.begin(), pending_data.begin() + num_bytes);
 452 }
 453