git.m6w6.name Git - awesomized/libmemcached/blob - libmemcached/dump.cc

   1 /*  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
   2  *
   3  *  Libmemcached library
   4  *
   5  *  Copyright (C) 2011 Data Differential, http://datadifferential.com/
   6  *
   7  *  Redistribution and use in source and binary forms, with or without
   8  *  modification, are permitted provided that the following conditions are
   9  *  met:
  10  *
  11  *      * Redistributions of source code must retain the above copyright
  12  *  notice, this list of conditions and the following disclaimer.
  13  *
  14  *      * Redistributions in binary form must reproduce the above
  15  *  copyright notice, this list of conditions and the following disclaimer
  16  *  in the documentation and/or other materials provided with the
  17  *  distribution.
  18  *
  19  *      * The names of its contributors may not be used to endorse or
  20  *  promote products derived from this software without specific prior
  21  *  written permission.
  22  *
  23  *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  24  *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  25  *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  26  *  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  27  *  OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  28  *  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  29  *  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  30  *  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  31  *  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  32  *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  33  *  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  34  *
  35  */
  36
  37 /*
  38   We use this to dump all keys.
  39
  40   At this point we only support a callback method. This could be optimized by first
  41   calling items and finding active slabs. For the moment though we just loop through
  42   all slabs on servers and "grab" the keys.
  43 */
  44
  45 #include <libmemcached/common.h>
  46
  47 static memcached_return_t ascii_dump(memcached_st *memc, memcached_dump_fn *callback, void *context, uint32_t number_of_callbacks)
  48 {
  49   for (uint32_t server_key= 0; server_key < memcached_server_count(memc); server_key++)
  50   {
  51     memcached_server_write_instance_st instance= memcached_server_instance_fetch(memc, server_key);
  52
  53     bool exit_slab_loop= false;
  54     /* MAX_NUMBER_OF_SLAB_CLASSESdefined to 200 in Memcached 1.4.10 */
  55     for (uint32_t x= 0; x < 200 and (exit_slab_loop == false); x++)
  56     {
  57       char buffer[MEMCACHED_DEFAULT_COMMAND_SIZE];
  58       int buffer_length= snprintf(buffer, sizeof(buffer), "%u", x);
  59       if (size_t(buffer_length) >= sizeof(buffer) or buffer_length < 0)
  60       {
  61         return memcached_set_error(*memc, MEMCACHED_MEMORY_ALLOCATION_FAILURE, MEMCACHED_AT,
  62                                    memcached_literal_param("snprintf(MEMCACHED_DEFAULT_COMMAND_SIZE)"));
  63       }
  64
  65       libmemcached_io_vector_st vector[]=
  66       {
  67         { memcached_literal_param("stats cachedump ") },
  68         { buffer, buffer_length },
  69         { memcached_literal_param(" 0 0\r\n") }
  70       };
  71
  72       memcached_return_t vdo_rc;
  73       if (memcached_success((vdo_rc= memcached_vdo(instance, vector, 3, true))))
  74       {
  75         while (1)
  76         {
  77           memcached_return_t response_rc= memcached_response(instance, buffer, MEMCACHED_DEFAULT_COMMAND_SIZE, NULL);
  78           fprintf(stderr, "%s:%d %s\n", __FILE__, __LINE__, memcached_strerror(NULL, response_rc));
  79           if (response_rc == MEMCACHED_ITEM)
  80           {
  81             char *string_ptr, *end_ptr;
  82
  83             string_ptr= buffer;
  84             string_ptr+= 5; /* Move past ITEM */
  85
  86             for (end_ptr= string_ptr; isgraph(*end_ptr); end_ptr++) {} ;
  87
  88             char *key= string_ptr;
  89             key[(size_t)(end_ptr-string_ptr)]= 0;
  90
  91             for (uint32_t callback_counter= 0; callback_counter < number_of_callbacks; callback_counter++)
  92             {
  93               memcached_return_t callback_rc= (*callback[callback_counter])(memc, key, (size_t)(end_ptr-string_ptr), context);
  94               if (callback_rc != MEMCACHED_SUCCESS)
  95               {
  96                 // @todo build up a message for the error from the value
  97                 memcached_set_error(*instance, callback_rc, MEMCACHED_AT);
  98                 break;
  99               }
 100             }
 101           }
 102           else if (response_rc == MEMCACHED_END)
 103           {
 104             // No additional items were found
 105             exit_slab_loop= true;
 106             break;
 107           }
 108           else if (response_rc == MEMCACHED_SERVER_ERROR or response_rc == MEMCACHED_CLIENT_ERROR)
 109           {
 110             /* If we try to request stats cachedump for a slab class that is too big
 111              * the server will return an incorrect error message:
 112              * "MEMCACHED_SERVER_ERROR failed to allocate memory"
 113              * This isn't really a fatal error, so let's just skip it. I want to
 114              * fix the return value from the memcached server to a CLIENT_ERROR,
 115              * so let's add support for that as well right now.
 116            */
 117             exit_slab_loop= true;
 118             break;
 119           }
 120           else
 121           {
 122             memcached_set_error(*instance, response_rc, MEMCACHED_AT);
 123             exit_slab_loop= true;
 124             break;
 125           }
 126         }
 127       }
 128       else
 129       {
 130         exit_slab_loop= true;
 131         memcached_set_error(*instance, vdo_rc, MEMCACHED_AT);
 132       }
 133       fprintf(stderr, "Was able to request %u slab\n", x);
 134     }
 135   }
 136
 137   return memcached_has_current_error(*memc) ? MEMCACHED_SOME_ERRORS : MEMCACHED_SUCCESS;
 138 }
 139
 140 memcached_return_t memcached_dump(memcached_st *ptr, memcached_dump_fn *callback, void *context, uint32_t number_of_callbacks)
 141 {
 142   memcached_return_t rc;
 143   if (memcached_failed(rc= initialize_query(ptr, true)))
 144   {
 145     return rc;
 146   }
 147
 148   /*
 149     No support for Binary protocol yet
 150     @todo Fix this so that we just flush, switch to ascii, and then go back to binary.
 151   */
 152   if (memcached_is_binary(ptr))
 153   {
 154     return memcached_set_error(*ptr, MEMCACHED_NOT_SUPPORTED, MEMCACHED_AT, memcached_literal_param("Binary protocol is not supported for memcached_dump()"));
 155   }
 156
 157   return ascii_dump(ptr, callback, context, number_of_callbacks);
 158 }