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