git.m6w6.name Git - m6w6/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   host->sockaddr_inited= MEMCACHED_NOT_ALLOCATED;
  65 }
  66
  67 void server_list_free(memcached_st *ptr, memcached_server_st *servers)
  68 {
  69   unsigned int x;
  70
  71   if (servers == NULL)
  72     return;
  73
  74   for (x= 0; x < servers->count; x++)
  75     if (servers[x].address_info)
  76       freeaddrinfo(servers[x].address_info);
  77
  78   if (ptr && ptr->call_free)
  79     ptr->call_free(ptr, servers);
  80   else
  81     free(servers);
  82 }
  83
  84 memcached_return memcached_server_push(memcached_st *ptr, memcached_server_st *list)
  85 {
  86   unsigned int x;
  87   uint16_t count;
  88   memcached_server_st *new_host_list;
  89
  90   if (!list)
  91     return MEMCACHED_SUCCESS;
  92
  93   count= list[0].count;
  94
  95   if (ptr->call_realloc)
  96     new_host_list=
  97       (memcached_server_st *)ptr->call_realloc(ptr, ptr->hosts,
  98                                                sizeof(memcached_server_st) * (count + ptr->number_of_hosts));
  99   else
 100     new_host_list=
 101       (memcached_server_st *)realloc(ptr->hosts,
 102                                      sizeof(memcached_server_st) * (count + ptr->number_of_hosts));
 103
 104   if (!new_host_list)
 105     return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
 106
 107   ptr->hosts= new_host_list;
 108
 109   for (x= 0; x < count; x++)
 110   {
 111     WATCHPOINT_ASSERT(list[x].hostname[0] != 0);
 112     host_reset(ptr, &ptr->hosts[ptr->number_of_hosts], list[x].hostname,
 113                list[x].port, list[x].type);
 114     ptr->number_of_hosts++;
 115   }
 116   ptr->hosts[0].count= ptr->number_of_hosts;
 117
 118   if (ptr->number_of_hosts > 1)
 119     qsort(ptr->hosts, ptr->number_of_hosts, sizeof(memcached_server_st), compare_servers);
 120
 121   rebalance_wheel(ptr);
 122
 123   return MEMCACHED_SUCCESS;
 124 }
 125
 126 memcached_return memcached_server_add_unix_socket(memcached_st *ptr, char *filename)
 127 {
 128   if (!filename)
 129     return MEMCACHED_FAILURE;
 130
 131   return server_add(ptr, filename, 0, MEMCACHED_CONNECTION_UNIX_SOCKET);
 132 }
 133
 134 memcached_return memcached_server_add_udp(memcached_st *ptr,
 135                                           char *hostname,
 136                                           unsigned int port)
 137 {
 138   if (!port)
 139     port= MEMCACHED_DEFAULT_PORT;
 140
 141   if (!hostname)
 142     hostname= "localhost";
 143
 144   return server_add(ptr, hostname, port, MEMCACHED_CONNECTION_UDP);
 145 }
 146
 147 memcached_return memcached_server_add(memcached_st *ptr,
 148                                       char *hostname,
 149                                       unsigned int port)
 150 {
 151   if (!port)
 152     port= MEMCACHED_DEFAULT_PORT;
 153
 154   if (!hostname)
 155     hostname= "localhost";
 156
 157   return server_add(ptr, hostname, port, MEMCACHED_CONNECTION_TCP);
 158 }
 159
 160 static memcached_return server_add(memcached_st *ptr, char *hostname,
 161                                    unsigned int port,
 162                                    memcached_connection type)
 163 {
 164   memcached_server_st *new_host_list;
 165   LIBMEMCACHED_MEMCACHED_SERVER_ADD_START();
 166
 167
 168   if (ptr->call_realloc)
 169     new_host_list= (memcached_server_st *)ptr->call_realloc(ptr, ptr->hosts,
 170                                                             sizeof(memcached_server_st) * (ptr->number_of_hosts+1));
 171   else
 172     new_host_list= (memcached_server_st *)realloc(ptr->hosts,
 173                                                   sizeof(memcached_server_st) * (ptr->number_of_hosts+1));
 174   if (new_host_list == NULL)
 175     return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
 176
 177   ptr->hosts= new_host_list;
 178
 179   host_reset(ptr, &ptr->hosts[ptr->number_of_hosts], hostname, port, type);
 180   ptr->number_of_hosts++;
 181   ptr->hosts[0].count++;
 182
 183   if (ptr->number_of_hosts > 1)
 184     qsort(ptr->hosts, ptr->number_of_hosts, sizeof(memcached_server_st), compare_servers);
 185
 186   rebalance_wheel(ptr);
 187
 188   LIBMEMCACHED_MEMCACHED_SERVER_ADD_END();
 189
 190   return MEMCACHED_SUCCESS;
 191 }
 192
 193 memcached_server_st *memcached_server_list_append(memcached_server_st *ptr,
 194                                                   char *hostname, unsigned int port,
 195                                                   memcached_return *error)
 196 {
 197   unsigned int count;
 198   memcached_server_st *new_host_list;
 199
 200   if (hostname == NULL || error == NULL)
 201     return NULL;
 202
 203   if (!port)
 204     port= MEMCACHED_DEFAULT_PORT;
 205
 206   /* Increment count for hosts */
 207   count= 1;
 208   if (ptr != NULL)
 209   {
 210     count+= ptr[0].count;
 211   }
 212
 213   new_host_list= (memcached_server_st *)realloc(ptr, sizeof(memcached_server_st) * count);
 214   if (!new_host_list)
 215   {
 216     *error= MEMCACHED_MEMORY_ALLOCATION_FAILURE;
 217     return NULL;
 218   }
 219
 220   host_reset(NULL, &new_host_list[count-1], hostname, port, MEMCACHED_CONNECTION_TCP);
 221
 222   /* Backwards compatibility hack */
 223   new_host_list[0].count++;
 224
 225   count= new_host_list[0].count;
 226
 227   if (new_host_list[0].count > 1)
 228     qsort(new_host_list, count, sizeof(memcached_server_st), compare_servers);
 229
 230   new_host_list[0].count= count;
 231
 232
 233   *error= MEMCACHED_SUCCESS;
 234   return new_host_list;
 235 }
 236
 237 unsigned int memcached_server_list_count(memcached_server_st *ptr)
 238 {
 239   if (ptr == NULL)
 240     return 0;
 241
 242   return ptr[0].count;
 243 }
 244
 245 void memcached_server_list_free(memcached_server_st *ptr)
 246 {
 247   server_list_free(NULL, ptr);
 248 }