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

   1 #include "common.h"
   2
   3 /* Protoypes (static) */
   4 static memcached_return server_add(memcached_st *ptr, char *hostname,
   5                                    unsigned int port,
   6                                    memcached_connection type);
   7 memcached_return update_continuum(memcached_st *ptr);
   8
   9 static int compare_servers(const void *p1, const void *p2)
  10 {
  11   int return_value;
  12   memcached_server_st *a= (memcached_server_st *)p1;
  13   memcached_server_st *b= (memcached_server_st *)p2;
  14
  15   return_value= strcmp(a->hostname, b->hostname);
  16
  17   if (return_value == 0)
  18   {
  19     return_value= (int) (a->port - b->port);
  20   }
  21
  22   return return_value;
  23 }
  24
  25 void sort_hosts(memcached_st *ptr)
  26 {
  27   if (ptr->number_of_hosts)
  28   {
  29     qsort(ptr->hosts, ptr->number_of_hosts, sizeof(memcached_server_st), compare_servers);
  30     ptr->hosts[0].count= ptr->number_of_hosts;
  31   }
  32 }
  33
  34
  35 memcached_return run_distribution(memcached_st *ptr)
  36 {
  37   switch (ptr->distribution)
  38   {
  39   case MEMCACHED_DISTRIBUTION_CONSISTENT:
  40   case MEMCACHED_DISTRIBUTION_CONSISTENT_KETAMA:
  41     return update_continuum(ptr);
  42   case MEMCACHED_DISTRIBUTION_MODULA:
  43     if (ptr->flags & MEM_USE_SORT_HOSTS)
  44       sort_hosts(ptr);
  45     break;
  46   default:
  47     WATCHPOINT_ASSERT(0); /* We have added a distribution without extending the logic */
  48   }
  49
  50   return MEMCACHED_SUCCESS;
  51 }
  52
  53 static void host_reset(memcached_st *ptr, memcached_server_st *host,
  54                        char *hostname, unsigned int port,
  55                        memcached_connection type)
  56 {
  57   memset(host,  0, sizeof(memcached_server_st));
  58   strncpy(host->hostname, hostname, MEMCACHED_MAX_HOST_LENGTH - 1);
  59   host->root= ptr ? ptr : NULL;
  60   host->port= port;
  61   host->fd= -1;
  62   host->type= type;
  63   host->read_ptr= host->read_buffer;
  64   if (ptr)
  65     host->next_retry= ptr->retry_timeout;
  66   host->sockaddr_inited= MEMCACHED_NOT_ALLOCATED;
  67 }
  68
  69 void server_list_free(memcached_st *ptr, memcached_server_st *servers)
  70 {
  71   unsigned int x;
  72
  73   if (servers == NULL)
  74     return;
  75
  76   for (x= 0; x < servers->count; x++)
  77     if (servers[x].address_info)
  78     {
  79       freeaddrinfo(servers[x].address_info);
  80       servers[x].address_info= NULL;
  81     }
  82
  83   if (ptr && ptr->call_free)
  84     ptr->call_free(ptr, servers);
  85   else
  86     free(servers);
  87 }
  88
  89 static int continuum_item_cmp(const void *t1, const void *t2)
  90 {
  91   memcached_continuum_item_st *ct1 = (memcached_continuum_item_st *)t1;
  92   memcached_continuum_item_st *ct2 = (memcached_continuum_item_st *)t2;
  93
  94   WATCHPOINT_ASSERT(ct1->value != 153);
  95   if (ct1->value == ct2->value)
  96     return 0;
  97   else if (ct1->value > ct2->value)
  98     return 1;
  99   else
 100     return -1;
 101 }
 102
 103 memcached_return update_continuum(memcached_st *ptr)
 104 {
 105   uint32_t index;
 106   uint32_t host_index;
 107   uint32_t continuum_index= 0;
 108   uint32_t value;
 109   memcached_server_st *list;
 110
 111   if (ptr->number_of_hosts > ptr->continuum_count)
 112   {
 113     memcached_continuum_item_st *new_ptr;
 114
 115     if (ptr->call_realloc)
 116       new_ptr= (memcached_continuum_item_st *)ptr->call_realloc(ptr, ptr->continuum, sizeof(memcached_continuum_item_st) * (ptr->number_of_hosts + MEMCACHED_CONTINUUM_ADDITION) * MEMCACHED_POINTS_PER_SERVER);
 117     else
 118       new_ptr= (memcached_continuum_item_st *)realloc(ptr->continuum, sizeof(memcached_continuum_item_st) * (ptr->number_of_hosts + MEMCACHED_CONTINUUM_ADDITION) * MEMCACHED_POINTS_PER_SERVER);
 119
 120     if (new_ptr == 0)
 121       return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
 122
 123     ptr->continuum= new_ptr;
 124     ptr->continuum_count= ptr->number_of_hosts + MEMCACHED_CONTINUUM_ADDITION;
 125   }
 126
 127   list = ptr->hosts;
 128   for (host_index = 0; host_index < ptr->number_of_hosts; ++host_index)
 129   {
 130     for(index= 1; index <= MEMCACHED_POINTS_PER_SERVER; ++index)
 131     {
 132       char sort_host[MEMCACHED_MAX_HOST_SORT_LENGTH]= "";
 133       size_t sort_host_length;
 134
 135       sort_host_length= snprintf(sort_host, MEMCACHED_MAX_HOST_SORT_LENGTH, "%s:%d-%d",
 136                                  list[host_index].hostname, list[host_index].port, index);
 137       WATCHPOINT_ASSERT(sort_host_length);
 138       value= generate_hash(ptr, sort_host, sort_host_length);
 139       ptr->continuum[continuum_index].index= host_index;
 140       ptr->continuum[continuum_index++].value= value;
 141     }
 142   }
 143
 144   WATCHPOINT_ASSERT(ptr->number_of_hosts * MEMCACHED_POINTS_PER_SERVER <= MEMCACHED_CONTINUUM_SIZE);
 145   qsort(ptr->continuum, ptr->number_of_hosts * MEMCACHED_POINTS_PER_SERVER, sizeof(memcached_continuum_item_st), continuum_item_cmp);
 146 #ifdef HAVE_DEBUG
 147   for (index= 0; index < ((ptr->number_of_hosts * MEMCACHED_POINTS_PER_SERVER) - 1); index++)
 148   {
 149     WATCHPOINT_ASSERT(ptr->continuum[index].value <= ptr->continuum[index + 1].value);
 150   }
 151 #endif
 152
 153   return MEMCACHED_SUCCESS;
 154 }
 155
 156
 157 memcached_return memcached_server_push(memcached_st *ptr, memcached_server_st *list)
 158 {
 159   unsigned int x;
 160   uint16_t count;
 161   memcached_server_st *new_host_list;
 162
 163   if (!list)
 164     return MEMCACHED_SUCCESS;
 165
 166   count= list[0].count;
 167
 168   if (ptr->call_realloc)
 169     new_host_list=
 170       (memcached_server_st *)ptr->call_realloc(ptr, ptr->hosts,
 171                                                sizeof(memcached_server_st) * (count + ptr->number_of_hosts));
 172   else
 173     new_host_list=
 174       (memcached_server_st *)realloc(ptr->hosts,
 175                                      sizeof(memcached_server_st) * (count + ptr->number_of_hosts));
 176
 177   if (!new_host_list)
 178     return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
 179
 180   ptr->hosts= new_host_list;
 181
 182   for (x= 0; x < count; x++)
 183   {
 184     WATCHPOINT_ASSERT(list[x].hostname[0] != 0);
 185     host_reset(ptr, &ptr->hosts[ptr->number_of_hosts], list[x].hostname,
 186                list[x].port, list[x].type);
 187     ptr->number_of_hosts++;
 188   }
 189   ptr->hosts[0].count= ptr->number_of_hosts;
 190
 191   return run_distribution(ptr);
 192 }
 193
 194 memcached_return memcached_server_add_unix_socket(memcached_st *ptr, char *filename)
 195 {
 196   if (!filename)
 197     return MEMCACHED_FAILURE;
 198
 199   return server_add(ptr, filename, 0, MEMCACHED_CONNECTION_UNIX_SOCKET);
 200 }
 201
 202 memcached_return memcached_server_add_udp(memcached_st *ptr,
 203                                           char *hostname,
 204                                           unsigned int port)
 205 {
 206   if (!port)
 207     port= MEMCACHED_DEFAULT_PORT;
 208
 209   if (!hostname)
 210     hostname= "localhost";
 211
 212   return server_add(ptr, hostname, port, MEMCACHED_CONNECTION_UDP);
 213 }
 214
 215 memcached_return memcached_server_add(memcached_st *ptr,
 216                                       char *hostname,
 217                                       unsigned int port)
 218 {
 219   if (!port)
 220     port= MEMCACHED_DEFAULT_PORT;
 221
 222   if (!hostname)
 223     hostname= "localhost";
 224
 225   return server_add(ptr, hostname, port, MEMCACHED_CONNECTION_TCP);
 226 }
 227
 228 static memcached_return server_add(memcached_st *ptr, char *hostname,
 229                                    unsigned int port,
 230                                    memcached_connection type)
 231 {
 232   memcached_server_st *new_host_list;
 233
 234   if (ptr->call_realloc)
 235     new_host_list= (memcached_server_st *)ptr->call_realloc(ptr, ptr->hosts,
 236                                                             sizeof(memcached_server_st) * (ptr->number_of_hosts+1));
 237   else
 238     new_host_list= (memcached_server_st *)realloc(ptr->hosts,
 239                                                   sizeof(memcached_server_st) * (ptr->number_of_hosts+1));
 240   if (new_host_list == NULL)
 241     return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
 242
 243   ptr->hosts= new_host_list;
 244
 245   host_reset(ptr, &ptr->hosts[ptr->number_of_hosts], hostname, port, type);
 246   ptr->number_of_hosts++;
 247   ptr->hosts[0].count= ptr->number_of_hosts;
 248
 249   return run_distribution(ptr);
 250 }
 251
 252 memcached_server_st *memcached_server_list_append(memcached_server_st *ptr,
 253                                                   char *hostname, unsigned int port,
 254                                                   memcached_return *error)
 255 {
 256   unsigned int count;
 257   memcached_server_st *new_host_list;
 258
 259   if (hostname == NULL || error == NULL)
 260     return NULL;
 261
 262   if (!port)
 263     port= MEMCACHED_DEFAULT_PORT;
 264
 265   /* Increment count for hosts */
 266   count= 1;
 267   if (ptr != NULL)
 268   {
 269     count+= ptr[0].count;
 270   }
 271
 272   new_host_list= (memcached_server_st *)realloc(ptr, sizeof(memcached_server_st) * count);
 273   if (!new_host_list)
 274   {
 275     *error= MEMCACHED_MEMORY_ALLOCATION_FAILURE;
 276     return NULL;
 277   }
 278
 279   host_reset(NULL, &new_host_list[count-1], hostname, port, MEMCACHED_CONNECTION_TCP);
 280
 281   /* Backwards compatibility hack */
 282   new_host_list[0].count= count;
 283
 284   *error= MEMCACHED_SUCCESS;
 285   return new_host_list;
 286 }
 287
 288 unsigned int memcached_server_list_count(memcached_server_st *ptr)
 289 {
 290   if (ptr == NULL)
 291     return 0;
 292
 293   return ptr[0].count;
 294 }
 295
 296 void memcached_server_list_free(memcached_server_st *ptr)
 297 {
 298   server_list_free(NULL, ptr);
 299 }