git.m6w6.name Git - awesomized/libmemcached/blob - libmemcached/connect.c

   1 #include "common.h"
   2 #include <netdb.h>
   3 #include <poll.h>
   4 #include <sys/time.h>
   5 #include <time.h>
   6
   7 static memcached_return_t set_hostinfo(memcached_server_st *server)
   8 {
   9   struct addrinfo *ai;
  10   struct addrinfo hints;
  11   char str_port[NI_MAXSERV];
  12   uint32_t counter= 5;
  13
  14   snprintf(str_port, NI_MAXSERV, "%u", (uint32_t)server->port);
  15
  16   memset(&hints, 0, sizeof(hints));
  17
  18  // hints.ai_family= AF_INET;
  19   if (server->type == MEMCACHED_CONNECTION_UDP)
  20   {
  21     hints.ai_protocol= IPPROTO_UDP;
  22     hints.ai_socktype= SOCK_DGRAM;
  23   }
  24   else
  25   {
  26     hints.ai_socktype= SOCK_STREAM;
  27     hints.ai_protocol= IPPROTO_TCP;
  28   }
  29
  30   while (--counter)
  31   {
  32     int e= getaddrinfo(server->hostname, str_port, &hints, &ai);
  33
  34     if (e == 0)
  35     {
  36       break;
  37     }
  38     else if (e == EAI_AGAIN)
  39     {
  40       struct timespec dream, rem;
  41
  42       dream.tv_nsec= 1000;
  43       dream.tv_sec= 0;
  44
  45       nanosleep(&dream, &rem);
  46
  47       continue;
  48     }
  49     else
  50     {
  51       WATCHPOINT_STRING(server->hostname);
  52       WATCHPOINT_STRING(gai_strerror(e));
  53       return MEMCACHED_HOST_LOOKUP_FAILURE;
  54     }
  55   }
  56
  57   if (server->address_info)
  58   {
  59     freeaddrinfo(server->address_info);
  60     server->address_info= NULL;
  61   }
  62   server->address_info= ai;
  63
  64   return MEMCACHED_SUCCESS;
  65 }
  66
  67 static memcached_return_t set_socket_options(memcached_server_st *ptr)
  68 {
  69   WATCHPOINT_ASSERT(ptr->fd != -1);
  70
  71   if (ptr->type == MEMCACHED_CONNECTION_UDP)
  72     return MEMCACHED_SUCCESS;
  73
  74 #ifdef HAVE_SNDTIMEO
  75   if (ptr->root->snd_timeout)
  76   {
  77     int error;
  78     struct timeval waittime;
  79
  80     waittime.tv_sec= 0;
  81     waittime.tv_usec= ptr->root->snd_timeout;
  82
  83     error= setsockopt(ptr->fd, SOL_SOCKET, SO_SNDTIMEO,
  84                       &waittime, (socklen_t)sizeof(struct timeval));
  85     WATCHPOINT_ASSERT(error == 0);
  86     if (error)
  87       return MEMCACHED_FAILURE;
  88   }
  89 #endif
  90
  91 #ifdef HAVE_RCVTIMEO
  92   if (ptr->root->rcv_timeout)
  93   {
  94     int error;
  95     struct timeval waittime;
  96
  97     waittime.tv_sec= 0;
  98     waittime.tv_usec= ptr->root->rcv_timeout;
  99
 100     error= setsockopt(ptr->fd, SOL_SOCKET, SO_RCVTIMEO,
 101                       &waittime, (socklen_t)sizeof(struct timeval));
 102     WATCHPOINT_ASSERT(error == 0);
 103     if (error)
 104       return MEMCACHED_FAILURE;
 105   }
 106 #endif
 107
 108
 109 #if defined(__MACH__) && defined(__APPLE__) || defined(__FreeBSD__)
 110   {
 111     int set = 1;
 112     int error= setsockopt(ptr->fd, SOL_SOCKET, SO_NOSIGPIPE, (void *)&set, sizeof(int));
 113
 114     // This is not considered a fatal error
 115     if (error == -1)
 116     {
 117       WATCHPOINT_ERRNO(errno);
 118       perror("setsockopt(SO_NOSIGPIPE)");
 119     }
 120   }
 121 #endif
 122
 123   if (ptr->root->flags.no_block)
 124   {
 125     int error;
 126     struct linger linger;
 127
 128     linger.l_onoff= 1;
 129     linger.l_linger= 0; /* By default on close() just drop the socket */
 130     error= setsockopt(ptr->fd, SOL_SOCKET, SO_LINGER,
 131                       &linger, (socklen_t)sizeof(struct linger));
 132     WATCHPOINT_ASSERT(error == 0);
 133     if (error)
 134       return MEMCACHED_FAILURE;
 135   }
 136
 137   if (ptr->root->flags.tcp_nodelay)
 138   {
 139     int flag= 1;
 140     int error;
 141
 142     error= setsockopt(ptr->fd, IPPROTO_TCP, TCP_NODELAY,
 143                       &flag, (socklen_t)sizeof(int));
 144     WATCHPOINT_ASSERT(error == 0);
 145     if (error)
 146       return MEMCACHED_FAILURE;
 147   }
 148
 149   if (ptr->root->flags.tcp_keepalive)
 150   {
 151     int flag= 1;
 152     int error;
 153
 154     error= setsockopt(ptr->fd, SOL_SOCKET, SO_KEEPALIVE,
 155                       &flag, (socklen_t)sizeof(int));
 156     WATCHPOINT_ASSERT(error == 0);
 157     if (error)
 158       return MEMCACHED_FAILURE;
 159   }
 160
 161 #ifdef TCP_KEEPIDLE
 162   if (ptr->root->tcp_keepidle > 0)
 163   {
 164     int error;
 165
 166     error= setsockopt(ptr->fd, IPPROTO_TCP, TCP_KEEPIDLE,
 167                       &ptr->root->tcp_keepidle, (socklen_t)sizeof(int));
 168     WATCHPOINT_ASSERT(error == 0);
 169     if (error)
 170       return MEMCACHED_FAILURE;
 171   }
 172 #endif
 173
 174   if (ptr->root->send_size > 0)
 175   {
 176     int error;
 177
 178     error= setsockopt(ptr->fd, SOL_SOCKET, SO_SNDBUF,
 179                       &ptr->root->send_size, (socklen_t)sizeof(int));
 180     WATCHPOINT_ASSERT(error == 0);
 181     if (error)
 182       return MEMCACHED_FAILURE;
 183   }
 184
 185   if (ptr->root->recv_size > 0)
 186   {
 187     int error;
 188
 189     error= setsockopt(ptr->fd, SOL_SOCKET, SO_RCVBUF,
 190                       &ptr->root->recv_size, (socklen_t)sizeof(int));
 191     WATCHPOINT_ASSERT(error == 0);
 192     if (error)
 193       return MEMCACHED_FAILURE;
 194   }
 195
 196   /* libmemcached will always use nonblocking IO to avoid write deadlocks */
 197   int flags;
 198
 199   do
 200     flags= fcntl(ptr->fd, F_GETFL, 0);
 201   while (flags == -1 && (errno == EINTR || errno == EAGAIN));
 202
 203   unlikely (flags == -1)
 204   {
 205     return MEMCACHED_CONNECTION_FAILURE;
 206   }
 207   else if ((flags & O_NONBLOCK) == 0)
 208   {
 209     int rval;
 210
 211     do
 212       rval= fcntl(ptr->fd, F_SETFL, flags | O_NONBLOCK);
 213     while (rval == -1 && (errno == EINTR || errno == EAGAIN));
 214
 215     unlikely (rval == -1)
 216     {
 217       return MEMCACHED_CONNECTION_FAILURE;
 218     }
 219   }
 220
 221   return MEMCACHED_SUCCESS;
 222 }
 223
 224 static memcached_return_t unix_socket_connect(memcached_server_st *ptr)
 225 {
 226   struct sockaddr_un servAddr;
 227
 228   if (ptr->fd == -1)
 229   {
 230     if ((ptr->fd= socket(AF_UNIX, SOCK_STREAM, 0)) < 0)
 231     {
 232       ptr->cached_errno= errno;
 233       return MEMCACHED_CONNECTION_SOCKET_CREATE_FAILURE;
 234     }
 235
 236     memset(&servAddr, 0, sizeof (struct sockaddr_un));
 237     servAddr.sun_family= AF_UNIX;
 238     strcpy(servAddr.sun_path, ptr->hostname); /* Copy filename */
 239
 240 test_connect:
 241     if (connect(ptr->fd,
 242                 (struct sockaddr *)&servAddr,
 243                 sizeof(servAddr)) < 0)
 244     {
 245       switch (errno)
 246       {
 247       case EINPROGRESS:
 248       case EALREADY:
 249       case EINTR:
 250         goto test_connect;
 251       case EISCONN: /* We were spinning waiting on connect */
 252         break;
 253       default:
 254         WATCHPOINT_ERRNO(errno);
 255         ptr->cached_errno= errno;
 256         return MEMCACHED_ERRNO;
 257       }
 258     }
 259   }
 260
 261   WATCHPOINT_ASSERT(ptr->fd != -1);
 262
 263   return MEMCACHED_SUCCESS;
 264 }
 265
 266 static memcached_return_t network_connect(memcached_server_st *ptr)
 267 {
 268   if (ptr->fd == -1)
 269   {
 270     struct addrinfo *use;
 271
 272     WATCHPOINT_ASSERT(ptr->cursor_active == 0);
 273
 274     if (! ptr->options.sockaddr_inited ||
 275         (!(ptr->root->flags.use_cache_lookups)))
 276     {
 277       memcached_return_t rc;
 278
 279       rc= set_hostinfo(ptr);
 280       if (rc != MEMCACHED_SUCCESS)
 281         return rc;
 282       ptr->options.sockaddr_inited= true;
 283     }
 284
 285     use= ptr->address_info;
 286     /* Create the socket */
 287     while (use != NULL)
 288     {
 289       /* Memcache server does not support IPV6 in udp mode, so skip if not ipv4 */
 290       if (ptr->type == MEMCACHED_CONNECTION_UDP && use->ai_family != AF_INET)
 291       {
 292         use= use->ai_next;
 293         continue;
 294       }
 295
 296       if ((ptr->fd= socket(use->ai_family,
 297                            use->ai_socktype,
 298                            use->ai_protocol)) < 0)
 299       {
 300         ptr->cached_errno= errno;
 301         WATCHPOINT_ERRNO(errno);
 302         return MEMCACHED_CONNECTION_SOCKET_CREATE_FAILURE;
 303       }
 304
 305       (void)set_socket_options(ptr);
 306
 307       /* connect to server */
 308       if ((connect(ptr->fd, use->ai_addr, use->ai_addrlen) == -1))
 309       {
 310         ptr->cached_errno= errno;
 311         if (errno == EINPROGRESS || /* nonblocking mode - first return, */
 312             errno == EALREADY) /* nonblocking mode - subsequent returns */
 313         {
 314           struct pollfd fds[1];
 315           fds[0].fd = ptr->fd;
 316           fds[0].events = POLLOUT;
 317
 318           int timeout= ptr->root->connect_timeout;
 319           if (ptr->root->flags.no_block == false)
 320             timeout= -1;
 321
 322           size_t loop_max= 5;
 323           while (--loop_max)
 324           {
 325             int error= poll(fds, 1, timeout);
 326
 327             switch (error)
 328             {
 329             case 1:
 330               loop_max= 1;
 331               break;
 332             case 0:
 333               continue;
 334               // A real error occurred and we need to completely bail
 335             default:
 336               WATCHPOINT_ERRNO(errno);
 337               switch (errno)
 338               {
 339 #ifdef TARGET_OS_LINUX
 340               case ERESTART:
 341 #endif
 342               case EINTR:
 343                 continue;
 344               default:
 345                 if (fds[0].revents & POLLERR)
 346                 {
 347                   int err;
 348                   socklen_t len= sizeof (err);
 349                   (void)getsockopt(ptr->fd, SOL_SOCKET, SO_ERROR, &err, &len);
 350                   ptr->cached_errno= (err == 0) ? errno : err;
 351                 }
 352
 353                 (void)close(ptr->fd);
 354                 ptr->fd= -1;
 355
 356                 break;
 357               }
 358             }
 359           }
 360         }
 361         else if (errno == EISCONN) /* we are connected :-) */
 362         {
 363           break;
 364         }
 365         else if (errno != EINTR)
 366         {
 367           (void)close(ptr->fd);
 368           ptr->fd= -1;
 369           break;
 370         }
 371       }
 372
 373 #ifdef LIBMEMCACHED_WITH_SASL_SUPPORT
 374       if (ptr->fd != -1 && ptr->root->sasl.callbacks != NULL)
 375       {
 376         memcached_return rc= memcached_sasl_authenticate_connection(ptr);
 377         if (rc != MEMCACHED_SUCCESS)
 378         {
 379           (void)close(ptr->fd);
 380           ptr->fd= -1;
 381
 382           return rc;
 383         }
 384       }
 385 #endif
 386
 387
 388       if (ptr->fd != -1)
 389       {
 390         return MEMCACHED_SUCCESS;
 391       }
 392       use = use->ai_next;
 393     }
 394   }
 395
 396   if (ptr->fd == -1)
 397   {
 398     WATCHPOINT_STRING("Never got a good file descriptor");
 399
 400     /* Failed to connect. schedule next retry */
 401     if (ptr->root->retry_timeout)
 402     {
 403       struct timeval next_time;
 404
 405       if (gettimeofday(&next_time, NULL) == 0)
 406         ptr->next_retry= next_time.tv_sec + ptr->root->retry_timeout;
 407     }
 408
 409     if (ptr->cached_errno == 0)
 410       return MEMCACHED_TIMEOUT;
 411
 412     return MEMCACHED_ERRNO; /* The last error should be from connect() */
 413   }
 414
 415   return MEMCACHED_SUCCESS; /* The last error should be from connect() */
 416 }
 417
 418 void set_last_disconnected_host(memcached_server_write_instance_st ptr)
 419 {
 420   // const_cast
 421   memcached_st *root= (memcached_st *)ptr->root;
 422
 423 #if 0
 424   WATCHPOINT_STRING(ptr->hostname);
 425   WATCHPOINT_NUMBER(ptr->port);
 426   WATCHPOINT_ERRNO(ptr->cached_errno);
 427 #endif
 428   if (root->last_disconnected_server)
 429     memcached_server_free(root->last_disconnected_server);
 430   root->last_disconnected_server= memcached_server_clone(NULL, ptr);
 431 }
 432
 433 memcached_return_t memcached_connect(memcached_server_write_instance_st ptr)
 434 {
 435   memcached_return_t rc= MEMCACHED_NO_SERVERS;
 436   LIBMEMCACHED_MEMCACHED_CONNECT_START();
 437
 438   /* both retry_timeout and server_failure_limit must be set in order to delay retrying a server on error. */
 439   WATCHPOINT_ASSERT(ptr->root);
 440   if (ptr->root->retry_timeout && ptr->next_retry)
 441   {
 442     struct timeval curr_time;
 443
 444     gettimeofday(&curr_time, NULL);
 445
 446     // We should optimize this to remove the allocation if the server was
 447     // the last server to die
 448     if (ptr->next_retry > curr_time.tv_sec)
 449     {
 450       set_last_disconnected_host(ptr);
 451
 452       return MEMCACHED_SERVER_MARKED_DEAD;
 453     }
 454   }
 455
 456   // If we are over the counter failure, we just fail. Reject host only
 457   // works if you have a set number of failures.
 458   if (ptr->root->server_failure_limit && ptr->server_failure_counter >= ptr->root->server_failure_limit)
 459   {
 460     set_last_disconnected_host(ptr);
 461
 462     // @todo fix this by fixing behavior to no longer make use of
 463     // memcached_st
 464     if (_is_auto_eject_host(ptr->root))
 465     {
 466       run_distribution((memcached_st *)ptr->root);
 467     }
 468
 469     return MEMCACHED_SERVER_MARKED_DEAD;
 470   }
 471
 472   /* We need to clean up the multi startup piece */
 473   switch (ptr->type)
 474   {
 475   case MEMCACHED_CONNECTION_UNKNOWN:
 476     WATCHPOINT_ASSERT(0);
 477     rc= MEMCACHED_NOT_SUPPORTED;
 478     break;
 479   case MEMCACHED_CONNECTION_UDP:
 480   case MEMCACHED_CONNECTION_TCP:
 481     rc= network_connect(ptr);
 482     break;
 483   case MEMCACHED_CONNECTION_UNIX_SOCKET:
 484     rc= unix_socket_connect(ptr);
 485     break;
 486   case MEMCACHED_CONNECTION_MAX:
 487   default:
 488     WATCHPOINT_ASSERT(0);
 489   }
 490
 491   if (rc == MEMCACHED_SUCCESS)
 492   {
 493     ptr->server_failure_counter= 0;
 494     ptr->next_retry= 0;
 495   }
 496   else
 497   {
 498     ptr->server_failure_counter++;
 499
 500     set_last_disconnected_host(ptr);
 501   }
 502
 503   LIBMEMCACHED_MEMCACHED_CONNECT_END();
 504
 505   return rc;
 506 }