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

   1 /*
   2   We use this to dump all keys.
   3
   4   At this point we only support a callback method. This could be optimized by first
   5   calling items and finding active slabs. For the moment though we just loop through
   6   all slabs on servers and "grab" the keys.
   7 */
   8
   9 #include "common.h"
  10 static memcached_return_t ascii_dump(memcached_st *ptr, memcached_dump_fn *callback, void *context, uint32_t number_of_callbacks)
  11 {
  12   memcached_return_t rc= MEMCACHED_SUCCESS;
  13   char buffer[MEMCACHED_DEFAULT_COMMAND_SIZE];
  14   size_t send_length;
  15   uint32_t server_key;
  16   uint32_t x;
  17
  18   unlikely (ptr->number_of_hosts == 0)
  19     return MEMCACHED_NO_SERVERS;
  20
  21   for (server_key= 0; server_key < ptr->number_of_hosts; server_key++)
  22   {
  23     /* 256 I BELIEVE is the upper limit of slabs */
  24     for (x= 0; x < 256; x++)
  25     {
  26       send_length= (size_t) snprintf(buffer, MEMCACHED_DEFAULT_COMMAND_SIZE,
  27                                      "stats cachedump %u 0 0\r\n", x);
  28
  29       rc= memcached_do(&ptr->hosts[server_key], buffer, send_length, 1);
  30
  31       unlikely (rc != MEMCACHED_SUCCESS)
  32         goto error;
  33
  34       while (1)
  35       {
  36         uint32_t callback_counter;
  37         rc= memcached_response(&ptr->hosts[server_key], buffer, MEMCACHED_DEFAULT_COMMAND_SIZE, NULL);
  38
  39         if (rc == MEMCACHED_ITEM)
  40         {
  41           char *string_ptr, *end_ptr;
  42           char *key;
  43
  44           string_ptr= buffer;
  45           string_ptr+= 5; /* Move past ITEM */
  46           for (end_ptr= string_ptr; isgraph(*end_ptr); end_ptr++);
  47           key= string_ptr;
  48           key[(size_t)(end_ptr-string_ptr)]= 0;
  49           for (callback_counter= 0; callback_counter < number_of_callbacks; callback_counter++)
  50           {
  51             rc= (*callback[callback_counter])(ptr, key, (size_t)(end_ptr-string_ptr), context);
  52             if (rc != MEMCACHED_SUCCESS)
  53               break;
  54           }
  55         }
  56         else if (rc == MEMCACHED_END)
  57           break;
  58         else if (rc == MEMCACHED_SERVER_ERROR || rc == MEMCACHED_CLIENT_ERROR)
  59         {
  60           /* If we try to request stats cachedump for a slab class that is too big
  61            * the server will return an incorrect error message:
  62            * "MEMCACHED_SERVER_ERROR failed to allocate memory"
  63            * This isn't really a fatal error, so let's just skip it. I want to
  64            * fix the return value from the memcached server to a CLIENT_ERROR,
  65            * so let's add support for that as well right now.
  66            */
  67           rc= MEMCACHED_END;
  68           break;
  69         }
  70         else
  71           goto error;
  72       }
  73     }
  74   }
  75
  76 error:
  77   if (rc == MEMCACHED_END)
  78     return MEMCACHED_SUCCESS;
  79   else
  80     return rc;
  81 }
  82
  83 memcached_return_t memcached_dump(memcached_st *ptr, memcached_dump_fn *callback, void *context, uint32_t number_of_callbacks)
  84 {
  85   /* No support for Binary protocol yet */
  86   if (ptr->flags.binary_protocol)
  87     return MEMCACHED_FAILURE;
  88
  89   return ascii_dump(ptr, callback, context, number_of_callbacks);
  90 }