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

   1 #include <memcached.h>
   2 #include "common.h"
   3
   4 /* Protoypes (static) */
   5 static memcached_return server_add(memcached_st *ptr, char *hostname,
   6                                    unsigned int port,
   7                                    memcached_connection type);
   8
   9 #define MEMCACHED_WHEEL_SIZE 1024
  10 #define MEMCACHED_STRIDE 4
  11 static void rebalance_wheel(memcached_st *ptr)
  12 {
  13   unsigned int x;
  14   unsigned int y;
  15   unsigned int latch;
  16
  17   /* Seed the Wheel */
  18   memset(ptr->wheel, 0, sizeof(unsigned int) * MEMCACHED_WHEEL_SIZE);
  19
  20   for (latch= y= x= 0; x < MEMCACHED_WHEEL_SIZE; x++, latch++)
  21   {
  22     if (latch == MEMCACHED_STRIDE)
  23     {
  24       y++;
  25       if (y == ptr->number_of_hosts)
  26         y= 0;
  27       latch= 0;
  28     }
  29
  30     ptr->wheel[x]= y;
  31   }
  32 }
  33
  34 static int compare_servers(const void *p1, const void *p2)
  35 {
  36   int return_value;
  37   memcached_server_st *a= (memcached_server_st *)p1;
  38   memcached_server_st *b= (memcached_server_st *)p2;
  39
  40   return_value= strcmp(a->hostname, b->hostname);
  41
  42   if (return_value == 0)
  43   {
  44     if (a->port > b->port)
  45       return_value++;
  46     else
  47       return_value--;
  48   }
  49
  50   return return_value;
  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       freeaddrinfo(servers[x].address_info);
  79
  80   if (ptr && ptr->call_free)
  81     ptr->call_free(ptr, servers);
  82   else
  83     free(servers);
  84 }
  85
  86 memcached_return memcached_server_push(memcached_st *ptr, memcached_server_st *list)
  87 {
  88   unsigned int x;
  89   uint16_t count;
  90   memcached_server_st *new_host_list;
  91
  92   if (!list)
  93     return MEMCACHED_SUCCESS;
  94
  95   count= list[0].count;
  96
  97   if (ptr->call_realloc)
  98     new_host_list=
  99       (memcached_server_st *)ptr->call_realloc(ptr, ptr->hosts,
 100                                                sizeof(memcached_server_st) * (count + ptr->number_of_hosts));
 101   else
 102     new_host_list=
 103       (memcached_server_st *)realloc(ptr->hosts,
 104                                      sizeof(memcached_server_st) * (count + ptr->number_of_hosts));
 105
 106   if (!new_host_list)
 107     return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
 108
 109   ptr->hosts= new_host_list;
 110
 111   for (x= 0; x < count; x++)
 112   {
 113     WATCHPOINT_ASSERT(list[x].hostname[0] != 0);
 114     host_reset(ptr, &ptr->hosts[ptr->number_of_hosts], list[x].hostname,
 115                list[x].port, list[x].type);
 116     ptr->number_of_hosts++;
 117   }
 118   ptr->hosts[0].count= ptr->number_of_hosts;
 119
 120   if (ptr->number_of_hosts > 1)
 121     qsort(ptr->hosts, ptr->number_of_hosts, sizeof(memcached_server_st), compare_servers);
 122
 123   rebalance_wheel(ptr);
 124
 125   return MEMCACHED_SUCCESS;
 126 }
 127
 128 memcached_return memcached_server_add_unix_socket(memcached_st *ptr, char *filename)
 129 {
 130   if (!filename)
 131     return MEMCACHED_FAILURE;
 132
 133   return server_add(ptr, filename, 0, MEMCACHED_CONNECTION_UNIX_SOCKET);
 134 }
 135
 136 memcached_return memcached_server_add_udp(memcached_st *ptr,
 137                                           char *hostname,
 138                                           unsigned int port)
 139 {
 140   if (!port)
 141     port= MEMCACHED_DEFAULT_PORT;
 142
 143   if (!hostname)
 144     hostname= "localhost";
 145
 146   return server_add(ptr, hostname, port, MEMCACHED_CONNECTION_UDP);
 147 }
 148
 149 memcached_return memcached_server_add(memcached_st *ptr,
 150                                       char *hostname,
 151                                       unsigned int port)
 152 {
 153   if (!port)
 154     port= MEMCACHED_DEFAULT_PORT;
 155
 156   if (!hostname)
 157     hostname= "localhost";
 158
 159   return server_add(ptr, hostname, port, MEMCACHED_CONNECTION_TCP);
 160 }
 161
 162 static memcached_return server_add(memcached_st *ptr, char *hostname,
 163                                    unsigned int port,
 164                                    memcached_connection type)
 165 {
 166   memcached_server_st *new_host_list;
 167   LIBMEMCACHED_MEMCACHED_SERVER_ADD_START();
 168
 169
 170   if (ptr->call_realloc)
 171     new_host_list= (memcached_server_st *)ptr->call_realloc(ptr, ptr->hosts,
 172                                                             sizeof(memcached_server_st) * (ptr->number_of_hosts+1));
 173   else
 174     new_host_list= (memcached_server_st *)realloc(ptr->hosts,
 175                                                   sizeof(memcached_server_st) * (ptr->number_of_hosts+1));
 176   if (new_host_list == NULL)
 177     return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
 178
 179   ptr->hosts= new_host_list;
 180
 181   host_reset(ptr, &ptr->hosts[ptr->number_of_hosts], hostname, port, type);
 182   ptr->number_of_hosts++;
 183   ptr->hosts[0].count++;
 184
 185   if (ptr->number_of_hosts > 1)
 186     qsort(ptr->hosts, ptr->number_of_hosts, sizeof(memcached_server_st), compare_servers);
 187
 188   rebalance_wheel(ptr);
 189
 190   LIBMEMCACHED_MEMCACHED_SERVER_ADD_END();
 191
 192   return MEMCACHED_SUCCESS;
 193 }
 194
 195 memcached_server_st *memcached_server_list_append(memcached_server_st *ptr,
 196                                                   char *hostname, unsigned int port,
 197                                                   memcached_return *error)
 198 {
 199   unsigned int count;
 200   memcached_server_st *new_host_list;
 201
 202   if (hostname == NULL || error == NULL)
 203     return NULL;
 204
 205   if (!port)
 206     port= MEMCACHED_DEFAULT_PORT;
 207
 208   /* Increment count for hosts */
 209   count= 1;
 210   if (ptr != NULL)
 211   {
 212     count+= ptr[0].count;
 213   }
 214
 215   new_host_list= (memcached_server_st *)realloc(ptr, sizeof(memcached_server_st) * count);
 216   if (!new_host_list)
 217   {
 218     *error= MEMCACHED_MEMORY_ALLOCATION_FAILURE;
 219     return NULL;
 220   }
 221
 222   host_reset(NULL, &new_host_list[count-1], hostname, port, MEMCACHED_CONNECTION_TCP);
 223
 224   /* Backwards compatibility hack */
 225   new_host_list[0].count++;
 226
 227   count= new_host_list[0].count;
 228
 229   if (new_host_list[0].count > 1)
 230     qsort(new_host_list, count, sizeof(memcached_server_st), compare_servers);
 231
 232   new_host_list[0].count= count;
 233
 234
 235   *error= MEMCACHED_SUCCESS;
 236   return new_host_list;
 237 }
 238
 239 unsigned int memcached_server_list_count(memcached_server_st *ptr)
 240 {
 241   if (ptr == NULL)
 242     return 0;
 243
 244   return ptr[0].count;
 245 }
 246
 247 void memcached_server_list_free(memcached_server_st *ptr)
 248 {
 249   server_list_free(NULL, ptr);
 250 }