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,
  45                                  key, key_length, expiration);
  46 }
  47
  48 static inline memcached_return_t binary_delete(memcached_st *ptr,
  49                                                uint32_t server_key,
  50                                                const char *key,
  51                                                size_t key_length,
  52                                                bool flush);
  53
  54 memcached_return_t memcached_delete_by_key(memcached_st *ptr,
  55                                            const char *group_key, size_t group_key_length,
  56                                            const char *key, size_t key_length,
  57                                            time_t expiration)
  58 {
  59   char buffer[MEMCACHED_DEFAULT_COMMAND_SIZE];
  60   memcached_server_write_instance_st instance;
  61
  62   LIBMEMCACHED_MEMCACHED_DELETE_START();
  63
  64   memcached_return_t rc;
  65   if (memcached_failed(rc= initialize_query(ptr)))
  66   {
  67     return rc;
  68   }
  69
  70   rc= memcached_validate_key_length(key_length,
  71                                     ptr->flags.binary_protocol);
  72
  73   unlikely (memcached_failed(rc))
  74     return rc;
  75
  76   unlikely (memcached_server_count(ptr) == 0)
  77     return MEMCACHED_NO_SERVERS;
  78
  79   uint32_t server_key= memcached_generate_hash_with_redistribution(ptr, group_key, group_key_length);
  80   instance= memcached_server_instance_fetch(ptr, server_key);
  81
  82   bool to_write= (ptr->flags.buffer_requests) ? false : true;
  83
  84   bool no_reply= (ptr->flags.no_reply);
  85
  86   if (ptr->flags.binary_protocol)
  87   {
  88     likely (! expiration)
  89     {
  90       rc= binary_delete(ptr, server_key, key, key_length, to_write);
  91     }
  92     else
  93     {
  94       rc= MEMCACHED_INVALID_ARGUMENTS;
  95     }
  96   }
  97   else
  98   {
  99     int send_length;
 100
 101     unlikely (expiration)
 102     {
 103        if ((instance->major_version == 1 &&
 104             instance->minor_version > 2) ||
 105            instance->major_version > 1)
 106        {
 107          rc= MEMCACHED_INVALID_ARGUMENTS;
 108          goto error;
 109        }
 110        else
 111        {
 112           /* ensure that we are connected, otherwise we might bump the
 113            * command counter before connection */
 114           if ((rc= memcached_connect(instance)) != MEMCACHED_SUCCESS)
 115           {
 116             WATCHPOINT_ERROR(rc);
 117             return rc;
 118           }
 119
 120           if (instance->minor_version == 0)
 121           {
 122              if (no_reply or to_write == false)
 123              {
 124                 /* We might get out of sync with the server if we
 125                  * send this command to a server newer than 1.2.x..
 126                  * disable no_reply and buffered mode.
 127                  */
 128                 to_write= true;
 129                 if (no_reply)
 130                    memcached_server_response_increment(instance);
 131                 no_reply= false;
 132              }
 133           }
 134           send_length= snprintf(buffer, MEMCACHED_DEFAULT_COMMAND_SIZE,
 135                                 "delete %.*s%.*s %u%s\r\n",
 136                                 memcached_print_array(ptr->_namespace),
 137                                 (int) key_length, key,
 138                                 (uint32_t)expiration,
 139                                 no_reply ? " noreply" :"" );
 140        }
 141     }
 142     else
 143     {
 144       send_length= snprintf(buffer, MEMCACHED_DEFAULT_COMMAND_SIZE,
 145                             "delete %.*s%.*s%s\r\n",
 146                             memcached_print_array(ptr->_namespace),
 147                             (int)key_length, key, no_reply ? " noreply" :"");
 148     }
 149
 150     if (send_length >= MEMCACHED_DEFAULT_COMMAND_SIZE || send_length < 0)
 151     {
 152       rc=  memcached_set_error(*ptr, MEMCACHED_MEMORY_ALLOCATION_FAILURE, MEMCACHED_AT,
 153                                memcached_literal_param("snprintf(MEMCACHED_DEFAULT_COMMAND_SIZE)"));
 154       goto error;
 155     }
 156
 157     if (ptr->flags.use_udp and to_write == false)
 158     {
 159       if (send_length > MAX_UDP_DATAGRAM_LENGTH - UDP_DATAGRAM_HEADER_LENGTH)
 160         return MEMCACHED_WRITE_FAILURE;
 161
 162       if (send_length + instance->write_buffer_offset > MAX_UDP_DATAGRAM_LENGTH)
 163       {
 164         memcached_io_write(instance, NULL, 0, true);
 165       }
 166     }
 167
 168     rc= memcached_do(instance, buffer, (size_t)send_length, to_write);
 169   }
 170
 171   if (rc != MEMCACHED_SUCCESS)
 172   {
 173     goto error;
 174   }
 175
 176   if (to_write == false)
 177   {
 178     rc= MEMCACHED_BUFFERED;
 179   }
 180   else if (no_reply == false)
 181   {
 182     rc= memcached_response(instance, buffer, MEMCACHED_DEFAULT_COMMAND_SIZE, NULL);
 183     if (rc == MEMCACHED_DELETED)
 184     {
 185       rc= MEMCACHED_SUCCESS;
 186     }
 187   }
 188
 189   if (rc == MEMCACHED_SUCCESS and ptr->delete_trigger)
 190   {
 191     ptr->delete_trigger(ptr, key, key_length);
 192   }
 193
 194 error:
 195   LIBMEMCACHED_MEMCACHED_DELETE_END();
 196   return rc;
 197 }
 198
 199 static inline memcached_return_t binary_delete(memcached_st *ptr,
 200                                                uint32_t server_key,
 201                                                const char *key,
 202                                                size_t key_length,
 203                                                bool flush)
 204 {
 205   memcached_server_write_instance_st instance;
 206   protocol_binary_request_delete request= {};
 207
 208   instance= memcached_server_instance_fetch(ptr, server_key);
 209
 210   request.message.header.request.magic= PROTOCOL_BINARY_REQ;
 211   if (ptr->flags.no_reply)
 212   {
 213     request.message.header.request.opcode= PROTOCOL_BINARY_CMD_DELETEQ;
 214   }
 215   else
 216   {
 217     request.message.header.request.opcode= PROTOCOL_BINARY_CMD_DELETE;
 218   }
 219   request.message.header.request.keylen= htons((uint16_t)(key_length + memcached_array_size(ptr->_namespace)));
 220   request.message.header.request.datatype= PROTOCOL_BINARY_RAW_BYTES;
 221   request.message.header.request.bodylen= htonl((uint32_t)(key_length + memcached_array_size(ptr->_namespace)));
 222
 223   if (ptr->flags.use_udp && ! flush)
 224   {
 225     size_t cmd_size= sizeof(request.bytes) + key_length;
 226     if (cmd_size > MAX_UDP_DATAGRAM_LENGTH - UDP_DATAGRAM_HEADER_LENGTH)
 227       return MEMCACHED_WRITE_FAILURE;
 228
 229     if (cmd_size + instance->write_buffer_offset > MAX_UDP_DATAGRAM_LENGTH)
 230       memcached_io_write(instance, NULL, 0, true);
 231   }
 232
 233   struct libmemcached_io_vector_st vector[]=
 234   {
 235     { sizeof(request.bytes), request.bytes},
 236     { memcached_array_size(ptr->_namespace), memcached_array_string(ptr->_namespace) },
 237     { key_length, key },
 238   };
 239
 240   memcached_return_t rc= MEMCACHED_SUCCESS;
 241
 242   if ((rc= memcached_vdo(instance, vector,  3, flush)) != MEMCACHED_SUCCESS)
 243   {
 244     memcached_io_reset(instance);
 245     rc= (rc == MEMCACHED_SUCCESS) ? MEMCACHED_WRITE_FAILURE : rc;
 246   }
 247
 248   unlikely (ptr->number_of_replicas > 0)
 249   {
 250     request.message.header.request.opcode= PROTOCOL_BINARY_CMD_DELETEQ;
 251
 252     for (uint32_t x= 0; x < ptr->number_of_replicas; ++x)
 253     {
 254       memcached_server_write_instance_st replica;
 255
 256       ++server_key;
 257       if (server_key == memcached_server_count(ptr))
 258         server_key= 0;
 259
 260       replica= memcached_server_instance_fetch(ptr, server_key);
 261
 262       if (memcached_vdo(replica, vector, 3, flush) != MEMCACHED_SUCCESS)
 263       {
 264         memcached_io_reset(replica);
 265       }
 266       else
 267       {
 268         memcached_server_response_decrement(replica);
 269       }
 270     }
 271   }
 272
 273   return rc;
 274 }