git.m6w6.name Git - m6w6/libmemcached/blob - libmemcached/memcached_connect.c

   1 #include "common.h"
   2 #include <netdb.h>
   3 #include <poll.h>
   4 #include <sys/time.h>
   5
   6 static memcached_return set_hostinfo(memcached_server_st *server)
   7 {
   8   struct addrinfo *ai;
   9   struct addrinfo hints;
  10   int e;
  11   char str_port[NI_MAXSERV];
  12
  13   sprintf(str_port, "%u", server->port);
  14
  15   memset(&hints, 0, sizeof(hints));
  16
  17  // hints.ai_family= AF_INET;
  18   if (server->type == MEMCACHED_CONNECTION_UDP)
  19   {
  20     hints.ai_protocol= IPPROTO_UDP;
  21     hints.ai_socktype= SOCK_DGRAM;
  22   }
  23   else
  24   {
  25     hints.ai_socktype= SOCK_STREAM;
  26     hints.ai_protocol= IPPROTO_TCP;
  27   }
  28
  29   e= getaddrinfo(server->hostname, str_port, &hints, &ai);
  30   if (e != 0)
  31   {
  32     WATCHPOINT_STRING(server->hostname);
  33     WATCHPOINT_STRING(gai_strerror(e));
  34     return MEMCACHED_HOST_LOOKUP_FAILURE;
  35   }
  36
  37   if (server->address_info)
  38   {
  39     freeaddrinfo(server->address_info);
  40     server->address_info= NULL;
  41   }
  42   server->address_info= ai;
  43
  44   return MEMCACHED_SUCCESS;
  45 }
  46
  47 static memcached_return set_socket_options(memcached_server_st *ptr)
  48 {
  49   WATCHPOINT_ASSERT(ptr->fd != -1);
  50
  51   if (ptr->type == MEMCACHED_CONNECTION_UDP)
  52     return MEMCACHED_SUCCESS;
  53
  54 #ifdef HAVE_SNDTIMEO
  55   if (ptr->root->snd_timeout)
  56   {
  57     int error;
  58     struct timeval waittime;
  59
  60     waittime.tv_sec= 0;
  61     waittime.tv_usec= ptr->root->snd_timeout;
  62
  63     error= setsockopt(ptr->fd, SOL_SOCKET, SO_SNDTIMEO,
  64                       &waittime, (socklen_t)sizeof(struct timeval));
  65     WATCHPOINT_ASSERT(error == 0);
  66   }
  67 #endif
  68
  69 #ifdef HAVE_RCVTIMEO
  70   if (ptr->root->rcv_timeout)
  71   {
  72     int error;
  73     struct timeval waittime;
  74
  75     waittime.tv_sec= 0;
  76     waittime.tv_usec= ptr->root->rcv_timeout;
  77
  78     error= setsockopt(ptr->fd, SOL_SOCKET, SO_RCVTIMEO,
  79                       &waittime, (socklen_t)sizeof(struct timeval));
  80     WATCHPOINT_ASSERT(error == 0);
  81   }
  82 #endif
  83
  84   if (ptr->root->flags & MEM_NO_BLOCK)
  85   {
  86     int error;
  87     struct linger linger;
  88
  89     linger.l_onoff= 1;
  90     linger.l_linger= 0; /* By default on close() just drop the socket */
  91     error= setsockopt(ptr->fd, SOL_SOCKET, SO_LINGER,
  92                       &linger, (socklen_t)sizeof(struct linger));
  93     WATCHPOINT_ASSERT(error == 0);
  94   }
  95
  96   if (ptr->root->flags & MEM_TCP_NODELAY)
  97   {
  98     int flag= 1;
  99     int error;
 100
 101     error= setsockopt(ptr->fd, IPPROTO_TCP, TCP_NODELAY,
 102                       &flag, (socklen_t)sizeof(int));
 103     WATCHPOINT_ASSERT(error == 0);
 104   }
 105
 106   if (ptr->root->send_size)
 107   {
 108     int error;
 109
 110     error= setsockopt(ptr->fd, SOL_SOCKET, SO_SNDBUF,
 111                       &ptr->root->send_size, (socklen_t)sizeof(int));
 112     WATCHPOINT_ASSERT(error == 0);
 113   }
 114
 115   if (ptr->root->recv_size)
 116   {
 117     int error;
 118
 119     error= setsockopt(ptr->fd, SOL_SOCKET, SO_RCVBUF,
 120                       &ptr->root->recv_size, (socklen_t)sizeof(int));
 121     WATCHPOINT_ASSERT(error == 0);
 122   }
 123
 124   /* For the moment, not getting a nonblocking mode will not be fatal */
 125   if ((ptr->root->flags & MEM_NO_BLOCK) || ptr->root->connect_timeout)
 126   {
 127     int flags;
 128
 129     flags= fcntl(ptr->fd, F_GETFL, 0);
 130     unlikely (flags != -1)
 131     {
 132       (void)fcntl(ptr->fd, F_SETFL, flags | O_NONBLOCK);
 133     }
 134   }
 135
 136   return MEMCACHED_SUCCESS;
 137 }
 138
 139 static memcached_return unix_socket_connect(memcached_server_st *ptr)
 140 {
 141   struct sockaddr_un servAddr;
 142   socklen_t addrlen;
 143
 144   if (ptr->fd == -1)
 145   {
 146     if ((ptr->fd= socket(AF_UNIX, SOCK_STREAM, 0)) < 0)
 147     {
 148       ptr->cached_errno= errno;
 149       return MEMCACHED_CONNECTION_SOCKET_CREATE_FAILURE;
 150     }
 151
 152     memset(&servAddr, 0, sizeof (struct sockaddr_un));
 153     servAddr.sun_family= AF_UNIX;
 154     strcpy(servAddr.sun_path, ptr->hostname); /* Copy filename */
 155
 156     addrlen= (socklen_t) (strlen(servAddr.sun_path) + sizeof(servAddr.sun_family));
 157
 158 test_connect:
 159     if (connect(ptr->fd,
 160                 (struct sockaddr *)&servAddr,
 161                 sizeof(servAddr)) < 0)
 162     {
 163       switch (errno)
 164       {
 165       case EINPROGRESS:
 166       case EALREADY:
 167       case EINTR:
 168         goto test_connect;
 169       case EISCONN: /* We were spinning waiting on connect */
 170         break;
 171       default:
 172         WATCHPOINT_ERRNO(errno);
 173         ptr->cached_errno= errno;
 174         return MEMCACHED_ERRNO;
 175       }
 176     }
 177   }
 178
 179   WATCHPOINT_ASSERT(ptr->fd != -1);
 180   return MEMCACHED_SUCCESS;
 181 }
 182
 183 static memcached_return network_connect(memcached_server_st *ptr)
 184 {
 185   if (ptr->fd == -1)
 186   {
 187     struct addrinfo *use;
 188
 189     if (!ptr->sockaddr_inited ||
 190         (!(ptr->root->flags & MEM_USE_CACHE_LOOKUPS)))
 191     {
 192       memcached_return rc;
 193
 194       rc= set_hostinfo(ptr);
 195       if (rc != MEMCACHED_SUCCESS)
 196         return rc;
 197       ptr->sockaddr_inited= true;
 198     }
 199
 200     use= ptr->address_info;
 201     /* Create the socket */
 202     while (use != NULL)
 203     {
 204       /* Memcache server does not support IPV6 in udp mode, so skip if not ipv4 */
 205       if (ptr->type == MEMCACHED_CONNECTION_UDP && use->ai_family != AF_INET)
 206       {
 207         use= use->ai_next;
 208         continue;
 209       }
 210
 211       if ((ptr->fd= socket(use->ai_family,
 212                            use->ai_socktype,
 213                            use->ai_protocol)) < 0)
 214       {
 215         ptr->cached_errno= errno;
 216         WATCHPOINT_ERRNO(errno);
 217         return MEMCACHED_CONNECTION_SOCKET_CREATE_FAILURE;
 218       }
 219
 220       (void)set_socket_options(ptr);
 221
 222       int flags= 0;
 223       if (ptr->root->connect_timeout)
 224       {
 225         flags= fcntl(ptr->fd, F_GETFL, 0);
 226         if (flags != -1 && !(flags & O_NONBLOCK))
 227           (void)fcntl(ptr->fd, F_SETFL, flags | O_NONBLOCK);
 228       }
 229
 230       /* connect to server */
 231       while (ptr->fd != -1 &&
 232              connect(ptr->fd, use->ai_addr, use->ai_addrlen) < 0)
 233       {
 234         ptr->cached_errno= errno;
 235         if (errno == EINPROGRESS || /* nonblocking mode - first return, */
 236             errno == EALREADY) /* nonblocking mode - subsequent returns */
 237         {
 238           struct pollfd fds[1];
 239           fds[0].fd = ptr->fd;
 240           fds[0].events = POLLOUT;
 241           int error= poll(fds, 1, ptr->root->connect_timeout);
 242
 243           if (error != 1 || fds[0].revents & POLLERR)
 244           {
 245             if (fds[0].revents & POLLERR)
 246             {
 247               int err;
 248               socklen_t len = sizeof (err);
 249               (void)getsockopt(ptr->fd, SOL_SOCKET, SO_ERROR, &err, &len);
 250               ptr->cached_errno= (err == 0) ? errno : err;
 251             }
 252
 253             (void)close(ptr->fd);
 254             ptr->fd= -1;
 255           }
 256         }
 257         else if (errno == EISCONN) /* we are connected :-) */
 258         {
 259           break;
 260         }
 261         else if (errno != EINTR)
 262         {
 263           (void)close(ptr->fd);
 264           ptr->fd= -1;
 265           break;
 266         }
 267       }
 268
 269       if (ptr->fd != -1)
 270       {
 271         /* restore flags */
 272         if (ptr->root->connect_timeout && (ptr->root->flags & MEM_NO_BLOCK) == 0)
 273           (void)fcntl(ptr->fd, F_SETFL, flags & ~O_NONBLOCK);
 274
 275         WATCHPOINT_ASSERT(ptr->cursor_active == 0);
 276         ptr->server_failure_counter= 0;
 277         return MEMCACHED_SUCCESS;
 278       }
 279       use = use->ai_next;
 280     }
 281   }
 282
 283   if (ptr->fd == -1)
 284   {
 285     /* Failed to connect. schedule next retry */
 286     if (ptr->root->retry_timeout)
 287     {
 288       struct timeval next_time;
 289
 290       if (gettimeofday(&next_time, NULL) == 0)
 291         ptr->next_retry= next_time.tv_sec + ptr->root->retry_timeout;
 292     }
 293     ptr->server_failure_counter+= 1;
 294     if (ptr->cached_errno == 0)
 295       return MEMCACHED_TIMEOUT;
 296     return MEMCACHED_ERRNO; /* The last error should be from connect() */
 297   }
 298
 299   ptr->server_failure_counter= 0;
 300   return MEMCACHED_SUCCESS; /* The last error should be from connect() */
 301 }
 302
 303
 304 memcached_return memcached_connect(memcached_server_st *ptr)
 305 {
 306   memcached_return rc= MEMCACHED_NO_SERVERS;
 307   LIBMEMCACHED_MEMCACHED_CONNECT_START();
 308
 309   /* both retry_timeout and server_failure_limit must be set in order to delay retrying a server on error. */
 310   WATCHPOINT_ASSERT(ptr->root);
 311   if (ptr->root->retry_timeout && ptr->root->server_failure_limit)
 312   {
 313     struct timeval next_time;
 314
 315     gettimeofday(&next_time, NULL);
 316
 317     /* if we've had too many consecutive errors on this server, mark it dead. */
 318     if (ptr->server_failure_counter > ptr->root->server_failure_limit)
 319     {
 320       ptr->next_retry= next_time.tv_sec + ptr->root->retry_timeout;
 321       ptr->server_failure_counter= 0;
 322     }
 323
 324     if (next_time.tv_sec < ptr->next_retry)
 325     {
 326       if (memcached_behavior_get(ptr->root, MEMCACHED_BEHAVIOR_AUTO_EJECT_HOSTS))
 327         run_distribution(ptr->root);
 328
 329       return MEMCACHED_SERVER_MARKED_DEAD;
 330     }
 331   }
 332
 333   /* We need to clean up the multi startup piece */
 334   switch (ptr->type)
 335   {
 336   case MEMCACHED_CONNECTION_UNKNOWN:
 337     WATCHPOINT_ASSERT(0);
 338     rc= MEMCACHED_NOT_SUPPORTED;
 339     break;
 340   case MEMCACHED_CONNECTION_UDP:
 341   case MEMCACHED_CONNECTION_TCP:
 342     rc= network_connect(ptr);
 343     break;
 344   case MEMCACHED_CONNECTION_UNIX_SOCKET:
 345     rc= unix_socket_connect(ptr);
 346     break;
 347   default:
 348     WATCHPOINT_ASSERT(0);
 349   }
 350
 351   LIBMEMCACHED_MEMCACHED_CONNECT_END();
 352
 353   return rc;
 354 }