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

   1 #include "common.h"
   2
   3 static memcached_return memcached_auto(memcached_st *ptr,
   4                                        char *verb,
   5                                        char *key, size_t key_length,
   6                                        unsigned int offset,
   7                                        uint64_t *value)
   8 {
   9   size_t send_length;
  10   char buffer[MEMCACHED_DEFAULT_COMMAND_SIZE];
  11   unsigned int server_key;
  12   uint8_t replicas= 0;
  13   memcached_return rc[MEMCACHED_MAX_REPLICAS];
  14
  15   unlikely (key_length == 0)
  16     return MEMCACHED_NO_KEY_PROVIDED;
  17
  18   unlikely (ptr->hosts == NULL || ptr->number_of_hosts == 0)
  19     return MEMCACHED_NO_SERVERS;
  20
  21   if ((ptr->flags & MEM_VERIFY_KEY) && (memcachd_key_test(&key, &key_length, 1) == MEMCACHED_BAD_KEY_PROVIDED))
  22     return MEMCACHED_BAD_KEY_PROVIDED;
  23
  24   server_key= memcached_generate_hash(ptr, key, key_length);
  25
  26   send_length= snprintf(buffer, MEMCACHED_DEFAULT_COMMAND_SIZE,
  27                         "%s %.*s %u\r\n", verb,
  28                         (int)key_length, key,
  29                         offset);
  30   unlikely (send_length >= MEMCACHED_DEFAULT_COMMAND_SIZE)
  31     return MEMCACHED_WRITE_FAILURE;
  32
  33   do
  34   {
  35     rc[replicas]= memcached_do(&ptr->hosts[server_key], buffer, send_length, 1);
  36     if (rc[replicas] != MEMCACHED_SUCCESS)
  37       goto error;
  38
  39     rc[replicas]= memcached_response(&ptr->hosts[server_key], buffer, MEMCACHED_DEFAULT_COMMAND_SIZE, NULL);
  40
  41     /*
  42       So why recheck responce? Because the protocol is brain dead :)
  43       The number returned might end up equaling one of the string
  44       values. Less chance of a mistake with strncmp() so we will
  45       use it. We still called memcached_response() though since it
  46       worked its magic for non-blocking IO.
  47     */
  48     if (!strncmp(buffer, "ERROR\r\n", 7))
  49     {
  50       *value= 0;
  51       rc[replicas]= MEMCACHED_PROTOCOL_ERROR;
  52     }
  53     else if (!strncmp(buffer, "NOT_FOUND\r\n", 11))
  54     {
  55       *value= 0;
  56       rc[replicas]= MEMCACHED_NOTFOUND;
  57     }
  58     else
  59     {
  60       *value= (uint64_t)strtoll(buffer, (char **)NULL, 10);
  61       rc[replicas]= MEMCACHED_SUCCESS;
  62     }
  63     /* On error we just jump to the next potential server */
  64 error:
  65     if (ptr->number_of_replicas > 1)
  66     {
  67       if (server_key == (ptr->number_of_hosts - 1))
  68         server_key= 0;
  69       else
  70         server_key++;
  71     }
  72   } while ((++replicas) < ptr->number_of_replicas);
  73
  74   /* As long as one object gets stored, we count this as a success */
  75   while (replicas--)
  76   {
  77     if (rc[replicas] == MEMCACHED_STORED)
  78       return MEMCACHED_SUCCESS;
  79   }
  80
  81   return rc[0];
  82 }
  83
  84 memcached_return memcached_increment(memcached_st *ptr,
  85                                      char *key, size_t key_length,
  86                                      uint32_t offset,
  87                                      uint64_t *value)
  88 {
  89   memcached_return rc;
  90
  91   LIBMEMCACHED_MEMCACHED_INCREMENT_START();
  92   rc= memcached_auto(ptr, "incr", key, key_length, offset, value);
  93   LIBMEMCACHED_MEMCACHED_INCREMENT_END();
  94
  95   return rc;
  96 }
  97
  98 memcached_return memcached_decrement(memcached_st *ptr,
  99                                      char *key, size_t key_length,
 100                                      uint32_t offset,
 101                                      uint64_t *value)
 102 {
 103   memcached_return rc;
 104
 105   LIBMEMCACHED_MEMCACHED_DECREMENT_START();
 106   rc= memcached_auto(ptr, "decr", key, key_length, offset, value);
 107   LIBMEMCACHED_MEMCACHED_DECREMENT_END();
 108
 109   return rc;
 110 }