git.m6w6.name Git - m6w6/libmemcached/blob - libmemcached/delete.cc

   1 /*  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
   2  *
   3  *  Libmemcached library
   4  *
   5  *  Copyright (C) 2011 Data Differential, http://datadifferential.com/
   6  *  Copyright (C) 2006-2009 Brian Aker All rights reserved.
   7  *
   8  *  Redistribution and use in source and binary forms, with or without
   9  *  modification, are permitted provided that the following conditions are
  10  *  met:
  11  *
  12  *      * Redistributions of source code must retain the above copyright
  13  *  notice, this list of conditions and the following disclaimer.
  14  *
  15  *      * Redistributions in binary form must reproduce the above
  16  *  copyright notice, this list of conditions and the following disclaimer
  17  *  in the documentation and/or other materials provided with the
  18  *  distribution.
  19  *
  20  *      * The names of its contributors may not be used to endorse or
  21  *  promote products derived from this software without specific prior
  22  *  written permission.
  23  *
  24  *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  25  *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  26  *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  27  *  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  28  *  OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  29  *  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  30  *  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  31  *  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  32  *  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  33  *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  34  *  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  35  *
  36  */
  37
  38 #include <libmemcached/common.h>
  39 #include <libmemcached/memcached/protocol_binary.h>
  40
  41 memcached_return_t memcached_delete(memcached_st *ptr, const char *key, size_t key_length,
  42                                     time_t expiration)
  43 {
  44   return memcached_delete_by_key(ptr, key, key_length, key, key_length, expiration);
  45 }
  46
  47 static inline memcached_return_t ascii_delete(memcached_server_write_instance_st instance,
  48                                               uint32_t ,
  49                                               const char *key,
  50                                               const size_t key_length,
  51                                               const bool reply,
  52                                               const bool flush)
  53 {
  54   libmemcached_io_vector_st vector[]=
  55   {
  56     { NULL, 0 },
  57     { memcached_literal_param("delete ") },
  58     { memcached_array_string(instance->root->_namespace), memcached_array_size(instance->root->_namespace) },
  59     { key, key_length },
  60     { " noreply", reply ? 0 : memcached_literal_param_size(" noreply") },
  61     { memcached_literal_param("\r\n") }
  62   };
  63
  64   if (memcached_is_udp(instance->root))
  65   {
  66     size_t send_length= io_vector_total_size(vector, 6);
  67
  68     if (send_length > MAX_UDP_DATAGRAM_LENGTH - UDP_DATAGRAM_HEADER_LENGTH)
  69     {
  70       return MEMCACHED_WRITE_FAILURE;
  71     }
  72
  73     if (send_length +instance->write_buffer_offset > MAX_UDP_DATAGRAM_LENGTH)
  74     {
  75       memcached_io_write(instance);
  76     }
  77   }
  78
  79   /* Send command header */
  80   return memcached_vdo(instance, vector, 6, flush);
  81 }
  82
  83 static inline memcached_return_t binary_delete(memcached_server_write_instance_st instance,
  84                                                uint32_t server_key,
  85                                                const char *key,
  86                                                const size_t key_length,
  87                                                const bool reply,
  88                                                const bool flush)
  89 {
  90   protocol_binary_request_delete request= {};
  91
  92   request.message.header.request.magic= PROTOCOL_BINARY_REQ;
  93   if (reply)
  94   {
  95     request.message.header.request.opcode= PROTOCOL_BINARY_CMD_DELETE;
  96   }
  97   else
  98   {
  99     request.message.header.request.opcode= PROTOCOL_BINARY_CMD_DELETEQ;
 100   }
 101   request.message.header.request.keylen= htons((uint16_t)(key_length + memcached_array_size(instance->root->_namespace)));
 102   request.message.header.request.datatype= PROTOCOL_BINARY_RAW_BYTES;
 103   request.message.header.request.bodylen= htonl((uint32_t)(key_length + memcached_array_size(instance->root->_namespace)));
 104
 105   if (memcached_is_udp(instance->root))
 106   {
 107     size_t cmd_size= sizeof(request.bytes) + key_length;
 108     if (cmd_size > MAX_UDP_DATAGRAM_LENGTH - UDP_DATAGRAM_HEADER_LENGTH)
 109     {
 110       return MEMCACHED_WRITE_FAILURE;
 111     }
 112
 113     if (cmd_size +instance->write_buffer_offset > MAX_UDP_DATAGRAM_LENGTH)
 114     {
 115       memcached_io_write(instance);
 116     }
 117   }
 118
 119   libmemcached_io_vector_st vector[]=
 120   {
 121     { NULL, 0 },
 122     { request.bytes, sizeof(request.bytes) },
 123     { memcached_array_string(instance->root->_namespace), memcached_array_size(instance->root->_namespace) },
 124     { key, key_length }
 125   };
 126
 127   memcached_return_t rc= MEMCACHED_SUCCESS;
 128
 129   if ((rc= memcached_vdo(instance, vector,  4, flush)) != MEMCACHED_SUCCESS)
 130   {
 131     memcached_io_reset(instance);
 132   }
 133
 134   if (instance->root->number_of_replicas > 0)
 135   {
 136     request.message.header.request.opcode= PROTOCOL_BINARY_CMD_DELETEQ;
 137
 138     for (uint32_t x= 0; x < instance->root->number_of_replicas; ++x)
 139     {
 140
 141       ++server_key;
 142       if (server_key == memcached_server_count(instance->root))
 143       {
 144         server_key= 0;
 145       }
 146
 147       memcached_server_write_instance_st replica= memcached_server_instance_fetch(instance->root, server_key);
 148
 149       if (memcached_vdo(replica, vector, 4, flush) != MEMCACHED_SUCCESS)
 150       {
 151         memcached_io_reset(replica);
 152       }
 153       else
 154       {
 155         memcached_server_response_decrement(replica);
 156       }
 157     }
 158   }
 159
 160   return rc;
 161 }
 162
 163 memcached_return_t memcached_delete_by_key(memcached_st *ptr,
 164                                            const char *group_key, size_t group_key_length,
 165                                            const char *key, size_t key_length,
 166                                            time_t expiration)
 167 {
 168   LIBMEMCACHED_MEMCACHED_DELETE_START();
 169
 170   memcached_return_t rc;
 171   if (memcached_failed(rc= initialize_query(ptr, true)))
 172   {
 173     return rc;
 174   }
 175
 176   rc= memcached_validate_key_length(key_length, ptr->flags.binary_protocol);
 177   if (memcached_failed(rc))
 178   {
 179     return rc;
 180   }
 181
 182   if (expiration)
 183   {
 184     return memcached_set_error(*ptr, MEMCACHED_INVALID_ARGUMENTS, MEMCACHED_AT,
 185                                memcached_literal_param("Memcached server version does not allow expiration of deleted items"));
 186   }
 187
 188   uint32_t server_key= memcached_generate_hash_with_redistribution(ptr, group_key, group_key_length);
 189   memcached_server_write_instance_st instance= memcached_server_instance_fetch(ptr, server_key);
 190
 191   bool buffering= memcached_is_buffering(instance->root);
 192   bool reply= memcached_is_replying(instance->root);
 193
 194   // If a delete trigger exists, we need a response, so no buffering/noreply
 195   if (ptr->delete_trigger)
 196   {
 197     if (buffering)
 198     {
 199       return memcached_set_error(*ptr, MEMCACHED_INVALID_ARGUMENTS, MEMCACHED_AT,
 200                                  memcached_literal_param("Delete triggers cannot be used if buffering is enabled"));
 201     }
 202
 203     if (reply == false)
 204     {
 205       return memcached_set_error(*ptr, MEMCACHED_INVALID_ARGUMENTS, MEMCACHED_AT,
 206                                  memcached_literal_param("Delete triggers cannot be used if MEMCACHED_BEHAVIOR_NOREPLY is set"));
 207     }
 208   }
 209
 210   if (memcached_is_binary(ptr))
 211   {
 212     rc= binary_delete(instance, server_key, key, key_length, reply, buffering ? false : true);
 213   }
 214   else
 215   {
 216     rc= ascii_delete(instance, server_key, key, key_length, reply, buffering ? false : true);
 217   }
 218
 219   if (rc == MEMCACHED_SUCCESS)
 220   {
 221     if (buffering == true)
 222     {
 223       rc= MEMCACHED_BUFFERED;
 224     }
 225     else if (reply == false)
 226     {
 227       rc= MEMCACHED_SUCCESS;
 228     }
 229     else
 230     {
 231       char buffer[MEMCACHED_DEFAULT_COMMAND_SIZE];
 232       rc= memcached_response(instance, buffer, MEMCACHED_DEFAULT_COMMAND_SIZE, NULL);
 233       if (rc == MEMCACHED_DELETED)
 234       {
 235         rc= MEMCACHED_SUCCESS;
 236         if (ptr->delete_trigger)
 237         {
 238           ptr->delete_trigger(ptr, key, key_length);
 239         }
 240       }
 241     }
 242   }
 243
 244   LIBMEMCACHED_MEMCACHED_DELETE_END();
 245   return memcached_set_error(*ptr, rc, MEMCACHED_AT );
 246 }