git.sesse.net Git - cubemap/blob - input.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 <errno.h>
  15 #include <vector>
  16 #include <string>
  17 #include <map>
  18
  19 #include "metacube.h"
  20 #include "mutexlock.h"
  21 #include "input.h"
  22 #include "server.h"
  23 #include "serverpool.h"
  24 #include "parse.h"
  25 #include "state.pb.h"
  26
  27 using namespace std;
  28
  29 extern ServerPool *servers;
  30
  31 // Extremely rudimentary URL parsing.
  32 bool parse_url(const string &url, string *host, string *port, string *path)
  33 {
  34         if (url.find("http://") != 0) {
  35                 return false;
  36         }
  37
  38         string rest = url.substr(strlen("http://"));
  39         size_t split = rest.find_first_of(":/");
  40         if (split == string::npos) {
  41                 // http://foo
  42                 *host = rest;
  43                 *port = "http";
  44                 *path = "/";
  45                 return true;
  46         }
  47
  48         *host = string(rest.begin(), rest.begin() + split);
  49         char ch = rest[split];  // Colon or slash.
  50         rest = string(rest.begin() + split + 1, rest.end());
  51
  52         if (ch == ':') {
  53                 // Parse the port.
  54                 split = rest.find_first_of('/');
  55                 if (split == string::npos) {
  56                         // http://foo:1234
  57                         *port = rest;
  58                         *path = "/";
  59                         return true;
  60                 } else {
  61                         // http://foo:1234/bar
  62                         *port = string(rest.begin(), rest.begin() + split);
  63                         *path = string(rest.begin() + split, rest.end());
  64                         return true;
  65                 }
  66         }
  67
  68         // http://foo/bar
  69         *port = "http";
  70         *path = rest;
  71         return true;
  72 }
  73
  74 Input::Input(const string &stream_id, const string &url)
  75         : state(NOT_CONNECTED),
  76           stream_id(stream_id),
  77           url(url),
  78           has_metacube_header(false),
  79           sock(-1)
  80 {
  81 }
  82
  83 Input::Input(const InputProto &serialized)
  84         : state(State(serialized.state())),
  85           stream_id(serialized.stream_id()),
  86           url(serialized.url()),
  87           request(serialized.request()),
  88           request_bytes_sent(serialized.request_bytes_sent()),
  89           response(serialized.response()),
  90           has_metacube_header(serialized.has_metacube_header()),
  91           sock(serialized.sock())
  92 {
  93         pending_data.resize(serialized.pending_data().size());
  94         memcpy(&pending_data[0], serialized.pending_data().data(), serialized.pending_data().size());
  95
  96         parse_url(url, &host, &port, &path);  // Don't care if it fails.
  97 }
  98
  99 InputProto Input::serialize() const
 100 {
 101         InputProto serialized;
 102         serialized.set_state(state);
 103         serialized.set_stream_id(stream_id);
 104         serialized.set_url(url);
 105         serialized.set_request(request);
 106         serialized.set_request_bytes_sent(request_bytes_sent);
 107         serialized.set_response(response);
 108         serialized.set_pending_data(string(pending_data.begin(), pending_data.end()));
 109         serialized.set_has_metacube_header(has_metacube_header);
 110         serialized.set_sock(sock);
 111         return serialized;
 112 }
 113
 114 void Input::run()
 115 {
 116         should_stop = false;
 117
 118         // Joinable is already the default, but it's good to be certain.
 119         pthread_attr_t attr;
 120         pthread_attr_init(&attr);
 121         pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE);
 122         pthread_create(&worker_thread, &attr, Input::do_work_thunk, this);
 123 }
 124
 125 void Input::stop()
 126 {
 127         should_stop = true;
 128
 129         if (pthread_join(worker_thread, NULL) == -1) {
 130                 perror("pthread_join");
 131                 exit(1);
 132         }
 133 }
 134
 135 void *Input::do_work_thunk(void *arg)
 136 {
 137         Input *input = static_cast<Input *>(arg);
 138         input->do_work();
 139         return NULL;
 140 }
 141
 142 int Input::lookup_and_connect(const string &host, const string &port)
 143 {
 144         addrinfo *ai;
 145         int err = getaddrinfo(host.c_str(), port.c_str(), NULL, &ai);
 146         if (err == -1) {
 147                 fprintf(stderr, "WARNING: Lookup of '%s' failed (%s).\n",
 148                         host.c_str(), gai_strerror(err));
 149                 freeaddrinfo(ai);
 150                 return -1;
 151         }
 152
 153         // Connect to everything in turn until we have a socket.
 154         while (ai && !should_stop) {
 155                 int sock = socket(ai->ai_family, SOCK_STREAM, IPPROTO_TCP);
 156                 if (sock == -1) {
 157                         // Could be e.g. EPROTONOSUPPORT. The show must go on.
 158                         continue;
 159                 }
 160
 161                 do {
 162                         err = connect(sock, ai->ai_addr, ai->ai_addrlen);
 163                 } while (err == -1 && errno == EINTR);
 164
 165                 if (err != -1) {
 166                         freeaddrinfo(ai);
 167                         return sock;
 168                 }
 169
 170                 ai = ai->ai_next;
 171         }
 172
 173         // Give the last one as error.
 174         fprintf(stderr, "WARNING: Connect to '%s' failed (%s)\n",
 175                 host.c_str(), strerror(errno));
 176         freeaddrinfo(ai);
 177         return -1;
 178 }
 179
 180 void Input::do_work()
 181 {
 182         while (!should_stop) {
 183                 if (state == SENDING_REQUEST || state == RECEIVING_HEADER || state == RECEIVING_DATA) {
 184                         // Since we are non-blocking, we need to wait for the right state first.
 185                         // Wait up to 50 ms, then check should_stop.
 186                         pollfd pfd;
 187                         pfd.fd = sock;
 188                         pfd.events = (state == SENDING_REQUEST) ? POLLOUT : POLLIN;
 189                         pfd.events |= POLLRDHUP;
 190
 191                         int nfds = poll(&pfd, 1, 50);
 192                         if (nfds == 0 || (nfds == -1 && errno == EAGAIN)) {
 193                                 continue;
 194                         }
 195                         if (nfds == -1) {
 196                                 perror("poll");
 197                                 state = CLOSING_SOCKET;
 198                         }
 199                 }
 200
 201                 switch (state) {
 202                 case NOT_CONNECTED:
 203                         request.clear();
 204                         request_bytes_sent = 0;
 205                         response.clear();
 206
 207                         if (!parse_url(url, &host, &port, &path)) {
 208                                 fprintf(stderr, "Failed to parse URL '%s'\n", url.c_str());
 209                                 break;
 210                         }
 211
 212                         sock = lookup_and_connect(host, port);
 213                         if (sock != -1) {
 214                                 // Yay, successful connect. Try to set it as nonblocking.
 215                                 int one = 1;
 216                                 if (ioctl(sock, FIONBIO, &one) == -1) {
 217                                         perror("ioctl(FIONBIO)");
 218                                         state = CLOSING_SOCKET;
 219                                 } else {
 220                                         state = SENDING_REQUEST;
 221                                         request = "GET " + path + " HTTP/1.0\r\nUser-Agent: cubemap\r\n\r\n";
 222                                         request_bytes_sent = 0;
 223                                 }
 224                         }
 225                         break;
 226                 case SENDING_REQUEST: {
 227                         size_t to_send = request.size() - request_bytes_sent;
 228                         int ret;
 229
 230                         do {
 231                                 ret = write(sock, request.data() + request_bytes_sent, to_send);
 232                         } while (ret == -1 && errno == EINTR);
 233
 234                         if (ret == -1) {
 235                                 perror("write");
 236                                 state = CLOSING_SOCKET;
 237                                 continue;
 238                         }
 239
 240                         assert(ret >= 0);
 241                         request_bytes_sent += ret;
 242
 243                         if (request_bytes_sent == request.size()) {
 244                                 state = RECEIVING_HEADER;
 245                         }
 246                         break;
 247                 }
 248                 case RECEIVING_HEADER: {
 249                         char buf[4096];
 250                         int ret;
 251
 252                         do {
 253                                 ret = read(sock, buf, sizeof(buf));
 254                         } while (ret == -1 && errno == EINTR);
 255
 256                         if (ret == -1) {
 257                                 perror("read");
 258                                 state = CLOSING_SOCKET;
 259                                 continue;
 260                         }
 261
 262                         if (ret == 0) {
 263                                 // This really shouldn't happen...
 264                                 fprintf(stderr, "Socket unexpectedly closed while reading header\n");
 265                                 state = CLOSING_SOCKET;
 266                                 continue;
 267                         }
 268
 269                         RequestParseStatus status = wait_for_double_newline(&response, buf, ret);
 270
 271                         if (status == RP_OUT_OF_SPACE) {
 272                                 fprintf(stderr, "WARNING: fd %d sent overlong response!\n", sock);
 273                                 state = CLOSING_SOCKET;
 274                                 continue;
 275                         } else if (status == RP_NOT_FINISHED_YET) {
 276                                 continue;
 277                         }
 278
 279                         // OK, so we're fine, but there might be some of the actual data after the response.
 280                         // We'll need to deal with that separately.
 281                         string extra_data;
 282                         if (status == RP_EXTRA_DATA) {
 283                                 char *ptr = static_cast<char *>(
 284                                         memmem(response.data(), response.size(), "\r\n\r\n", 4));
 285                                 assert(ptr != NULL);
 286                                 extra_data = string(ptr, &response[0] + response.size());
 287                                 response.resize(ptr - response.data());
 288                         }
 289
 290                         // TODO: Check that the response is 200, save the headers, etc.
 291
 292                         if (!extra_data.empty()) {
 293                                 process_data(&extra_data[0], extra_data.size());
 294                         }
 295
 296                         state = RECEIVING_DATA;
 297                         break;
 298                 }
 299                 case RECEIVING_DATA: {
 300                         char buf[4096];
 301                         int ret;
 302
 303                         do {
 304                                 ret = read(sock, buf, sizeof(buf));
 305                         } while (ret == -1 && errno == EINTR);
 306
 307                         if (ret == -1) {
 308                                 perror("read");
 309                                 state = CLOSING_SOCKET;
 310                                 continue;
 311                         }
 312
 313                         if (ret == 0) {
 314                                 // This really shouldn't happen...
 315                                 fprintf(stderr, "Socket unexpectedly closed while reading header\n");
 316                                 state = CLOSING_SOCKET;
 317                                 continue;
 318                         }
 319
 320                         process_data(buf, ret);
 321                         break;
 322                 }
 323                 case CLOSING_SOCKET: {
 324                         int err;
 325                         do {
 326                                 err = close(sock);
 327                         } while (err == -1 && errno == EINTR);
 328
 329                         if (err == -1) {
 330                                 perror("close");
 331                         }
 332
 333                         state = NOT_CONNECTED;
 334                         break;
 335                 }
 336                 default:
 337                         assert(false);
 338                 }
 339
 340                 // If we are still in NOT_CONNECTED, either something went wrong,
 341                 // or the connection just got closed.
 342                 // The earlier steps have already given the error message, if any.
 343                 if (state == NOT_CONNECTED && !should_stop) {
 344                         fprintf(stderr, "Waiting 0.2 second and restarting...\n");
 345                         usleep(200000);
 346                 }
 347         }
 348 }
 349
 350 void Input::process_data(char *ptr, size_t bytes)
 351 {
 352         pending_data.insert(pending_data.end(), ptr, ptr + bytes);
 353
 354         for ( ;; ) {
 355                 // If we don't have enough data (yet) for even the Metacube header, just return.
 356                 if (pending_data.size() < sizeof(metacube_block_header)) {
 357                         return;
 358                 }
 359
 360                 // Make sure we have the Metacube sync header at the start.
 361                 // We may need to skip over junk data (it _should_ not happen, though).
 362                 if (!has_metacube_header) {
 363                         char *ptr = static_cast<char *>(
 364                                 memmem(pending_data.data(), pending_data.size(),
 365                                        METACUBE_SYNC, strlen(METACUBE_SYNC)));
 366                         if (ptr == NULL) {
 367                                 // OK, so we didn't find the sync marker. We know then that
 368                                 // we do not have the _full_ marker in the buffer, but we
 369                                 // could have N-1 bytes. Drop everything before that,
 370                                 // and then give up.
 371                                 drop_pending_data(pending_data.size() - (strlen(METACUBE_SYNC) - 1));
 372                                 return;
 373                         } else {
 374                                 // Yay, we found the header. Drop everything (if anything) before it.
 375                                 drop_pending_data(ptr - pending_data.data());
 376                                 has_metacube_header = true;
 377
 378                                 // Re-check that we have the entire header; we could have dropped data.
 379                                 if (pending_data.size() < sizeof(metacube_block_header)) {
 380                                         return;
 381                                 }
 382                         }
 383                 }
 384
 385                 // Now it's safe to read the header.
 386                 metacube_block_header *hdr = reinterpret_cast<metacube_block_header *>(pending_data.data());
 387                 assert(memcmp(hdr->sync, METACUBE_SYNC, sizeof(hdr->sync)) == 0);
 388                 uint32_t size = ntohl(hdr->size);
 389                 uint32_t flags = ntohl(hdr->flags);
 390
 391                 // See if we have the entire block. If not, wait for more data.
 392                 if (pending_data.size() < sizeof(metacube_block_header) + size) {
 393                         return;
 394                 }
 395
 396                 // Send this block on to the data.
 397                 char *inner_data = pending_data.data() + sizeof(metacube_block_header);
 398                 if (flags & METACUBE_FLAGS_HEADER) {
 399                         string header(inner_data, inner_data + size);
 400                         servers->set_header(stream_id, header);
 401                 } else {
 402                         servers->add_data(stream_id, inner_data, size);
 403                 }
 404
 405                 // Consume the block. This isn't the most efficient way of dealing with things
 406                 // should we have many blocks, but these routines don't need to be too efficient
 407                 // anyway.
 408                 pending_data.erase(pending_data.begin(), pending_data.begin() + sizeof(metacube_block_header) + size);
 409                 has_metacube_header = false;
 410         }
 411 }
 412
 413 void Input::drop_pending_data(size_t num_bytes)
 414 {
 415         if (num_bytes == 0) {
 416                 return;
 417         }
 418         fprintf(stderr, "Warning: Dropping %lld junk bytes from stream, maybe it is not a Metacube stream?\n",
 419                 (long long)num_bytes);
 420         pending_data.erase(pending_data.begin(), pending_data.begin() + num_bytes);
 421 }
 422