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

   1 /*  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
   2  *
   3  *  LibMemcached
   4  *
   5  *  Copyright (C) 2011 Data Differential, http://datadifferential.com/
   6  *  Copyright (C) 2006-2009 Brian Aker
   7  *  All rights reserved.
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   9  *  Redistribution and use in source and binary forms, with or without
  10  *  modification, are permitted provided that the following conditions are
  11  *  met:
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  13  *      * Redistributions of source code must retain the above copyright
  14  *  notice, this list of conditions and the following disclaimer.
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  21  *      * The names of its contributors may not be used to endorse or
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  25  *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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  35  *  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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  38
  39
  40 #include <libmemcached/common.h>
  41
  42
  43 memcached_return_t memcached_purge(memcached_server_write_instance_st ptr)
  44 {
  45   memcached_return_t ret= MEMCACHED_SUCCESS;
  46   memcached_st *root= (memcached_st *)ptr->root;
  47
  48   if (memcached_is_purging(ptr->root) || /* already purging */
  49       (memcached_server_response_count(ptr) < ptr->root->io_msg_watermark &&
  50        ptr->io_bytes_sent < ptr->root->io_bytes_watermark) ||
  51       (ptr->io_bytes_sent >= ptr->root->io_bytes_watermark &&
  52        memcached_server_response_count(ptr) < 2))
  53   {
  54     return MEMCACHED_SUCCESS;
  55   }
  56
  57   /*
  58     memcached_io_write and memcached_response may call memcached_purge
  59     so we need to be able stop any recursion..
  60   */
  61   memcached_set_purging(root, true);
  62
  63   WATCHPOINT_ASSERT(ptr->fd != INVALID_SOCKET);
  64   /*
  65     Force a flush of the buffer to ensure that we don't have the n-1 pending
  66     requests buffered up..
  67   */
  68   if (memcached_io_write(ptr) == false)
  69   {
  70     memcached_set_purging(root, true);
  71
  72     return memcached_set_error(*ptr, MEMCACHED_WRITE_FAILURE, MEMCACHED_AT);
  73   }
  74   WATCHPOINT_ASSERT(ptr->fd != INVALID_SOCKET);
  75
  76   uint32_t no_msg= memcached_server_response_count(ptr) - 1;
  77   if (no_msg > 0)
  78   {
  79     memcached_result_st result;
  80     memcached_result_st *result_ptr;
  81
  82     /*
  83      * We need to increase the timeout, because we might be waiting for
  84      * data to be sent from the server (the commands was in the output buffer
  85      * and just flushed
  86    */
  87     const int32_t timeo= ptr->root->poll_timeout;
  88     root->poll_timeout= 2000;
  89
  90     result_ptr= memcached_result_create(root, &result);
  91     WATCHPOINT_ASSERT(result_ptr);
  92
  93     for (uint32_t x= 0; x < no_msg; x++)
  94     {
  95       memcached_result_reset(result_ptr);
  96       memcached_return_t rc= memcached_read_one_response(ptr, result_ptr);
  97       /*
  98        * Purge doesn't care for what kind of command results that is received.
  99        * The only kind of errors I care about if is I'm out of sync with the
 100        * protocol or have problems reading data from the network..
 101      */
 102       if (rc== MEMCACHED_PROTOCOL_ERROR or rc == MEMCACHED_UNKNOWN_READ_FAILURE or rc == MEMCACHED_READ_FAILURE)
 103       {
 104         WATCHPOINT_ERROR(rc);
 105         memcached_io_reset(ptr);
 106         ret= rc;
 107 #if 0
 108         ret= memcached_set_error(*ptr, rc, MEMCACHED_AT);
 109 #endif
 110       }
 111
 112       if (ptr->root->callbacks != NULL)
 113       {
 114         memcached_callback_st cb = *ptr->root->callbacks;
 115         if (memcached_success(rc))
 116         {
 117           for (uint32_t y= 0; y < cb.number_of_callback; y++)
 118           {
 119             rc = (*cb.callback[y])(ptr->root, result_ptr, cb.context);
 120             if (rc != MEMCACHED_SUCCESS)
 121             {
 122               break;
 123             }
 124           }
 125         }
 126       }
 127     }
 128
 129     memcached_result_free(result_ptr);
 130     root->poll_timeout= timeo;
 131   }
 132   memcached_set_purging(root, false);
 133
 134   return ret;
 135 }