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   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.
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  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,
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  32  *  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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  34  *  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  35  *
  36  */
  37
  38 #include <libmemcached/common.h>
  39
  40 char *memcached_fetch(memcached_st *ptr, char *key, size_t *key_length,
  41                       size_t *value_length,
  42                       uint32_t *flags,
  43                       memcached_return_t *error)
  44 {
  45   memcached_result_st *result_buffer= &ptr->result;
  46   memcached_return_t unused;
  47   if (not error)
  48     error= &unused;
  49
  50
  51   unlikely (ptr->flags.use_udp)
  52   {
  53     *error= MEMCACHED_NOT_SUPPORTED;
  54     return NULL;
  55   }
  56
  57   result_buffer= memcached_fetch_result(ptr, result_buffer, error);
  58
  59   if (result_buffer == NULL or *error != MEMCACHED_SUCCESS)
  60   {
  61     WATCHPOINT_ASSERT(result_buffer == NULL);
  62     *value_length= 0;
  63     return NULL;
  64   }
  65
  66   *value_length= memcached_string_length(&result_buffer->value);
  67
  68   if (key)
  69   {
  70     if (result_buffer->key_length > MEMCACHED_MAX_KEY)
  71     {
  72       *error= MEMCACHED_KEY_TOO_BIG;
  73       *value_length= 0;
  74
  75       return NULL;
  76     }
  77     strncpy(key, result_buffer->item_key, result_buffer->key_length); // For the binary protocol we will cut off the key :(
  78     *key_length= result_buffer->key_length;
  79   }
  80
  81   if (flags)
  82     *flags= result_buffer->item_flags;
  83
  84   return memcached_string_c_copy(&result_buffer->value);
  85 }
  86
  87 memcached_result_st *memcached_fetch_result(memcached_st *ptr,
  88                                             memcached_result_st *result,
  89                                             memcached_return_t *error)
  90 {
  91   memcached_server_st *server;
  92
  93   memcached_return_t unused;
  94   if (not error)
  95     error= &unused;
  96
  97   if (ptr->flags.use_udp)
  98   {
  99     *error= MEMCACHED_NOT_SUPPORTED;
 100     return NULL;
 101   }
 102
 103   if (not result)
 104   {
 105     if (not (result= memcached_result_create(ptr, NULL)))
 106     {
 107       *error= MEMCACHED_MEMORY_ALLOCATION_FAILURE;
 108       return NULL;
 109     }
 110   }
 111
 112   while ((server= memcached_io_get_readable_server(ptr)))
 113   {
 114     char buffer[MEMCACHED_DEFAULT_COMMAND_SIZE];
 115     *error= memcached_response(server, buffer, sizeof(buffer), result);
 116
 117     if (*error == MEMCACHED_SUCCESS)
 118     {
 119       return result;
 120     }
 121     else if (*error == MEMCACHED_END)
 122     {
 123       memcached_server_response_reset(server);
 124     }
 125     else if (*error != MEMCACHED_NOTFOUND)
 126     {
 127       break;
 128     }
 129   }
 130
 131   /* We have completed reading data */
 132   if (memcached_is_allocated(result))
 133   {
 134     memcached_result_free(result);
 135   }
 136   else
 137   {
 138     memcached_string_reset(&result->value);
 139   }
 140
 141   if (*error == MEMCACHED_NOTFOUND)
 142     *error= MEMCACHED_END;
 143
 144   if (*error == MEMCACHED_SUCCESS)
 145     *error= MEMCACHED_END;
 146
 147   return NULL;
 148 }
 149
 150 memcached_return_t memcached_fetch_execute(memcached_st *ptr,
 151                                            memcached_execute_fn *callback,
 152                                            void *context,
 153                                            uint32_t number_of_callbacks)
 154 {
 155   memcached_result_st *result= &ptr->result;
 156   memcached_return_t rc= MEMCACHED_FAILURE;
 157
 158   while ((result= memcached_fetch_result(ptr, result, &rc)))
 159   {
 160     if (memcached_success(rc))
 161     {
 162       for (uint32_t x= 0; x < number_of_callbacks; x++)
 163       {
 164         rc= (*callback[x])(ptr, result, context);
 165         if (memcached_failed(rc))
 166           break;
 167       }
 168     }
 169   }
 170   return rc;
 171 }