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

   1 /* LibMemcached
   2  * Copyright (C) 2006-2010 Brian Aker
   3  * All rights reserved.
   4  *
   5  * Use and distribution licensed under the BSD license.  See
   6  * the COPYING file in the parent directory for full text.
   7  *
   8  * Summary:
   9  *
  10  */
  11
  12 #include <libmemcached/common.h>
  13
  14 memcached_return_t memcached_vdo(memcached_server_write_instance_st instance,
  15                                  libmemcached_io_vector_st vector[],
  16                                  const size_t count,
  17                                  const bool with_flush)
  18 {
  19   memcached_return_t rc;
  20
  21   assert_msg(vector, "Invalid vector passed");
  22
  23   if (memcached_failed(rc= memcached_connect(instance)))
  24   {
  25     WATCHPOINT_ERROR(rc);
  26     assert_msg(instance->error_messages, "memcached_connect() returned an error but the memcached_server_write_instance_st showed none.");
  27     return rc;
  28   }
  29
  30   /*
  31   ** Since non buffering ops in UDP mode dont check to make sure they will fit
  32   ** before they start writing, if there is any data in buffer, clear it out,
  33   ** otherwise we might get a partial write.
  34   **/
  35   if (memcached_is_udp(instance->root))
  36   {
  37     if (vector[0].buffer or vector[0].length)
  38     {
  39       return memcached_set_error(*instance->root, MEMCACHED_NOT_SUPPORTED, MEMCACHED_AT,
  40                                  memcached_literal_param("UDP messages was attempted, but vector was not setup for it"));
  41     }
  42
  43     struct msghdr msg;
  44     memset(&msg, 0, sizeof(msg));
  45
  46     increment_udp_message_id(instance);
  47     vector[0].buffer= instance->write_buffer;
  48     vector[0].length= UDP_DATAGRAM_HEADER_LENGTH;
  49
  50     msg.msg_iov= (struct iovec*)vector;
  51     msg.msg_iovlen= count;
  52
  53     uint32_t retry= 5;
  54     while (--retry)
  55     {
  56       ssize_t sendmsg_length= ::sendmsg(instance->fd, &msg, 0);
  57       if (sendmsg_length > 0)
  58       {
  59         break;
  60       }
  61       else if (sendmsg_length < 0)
  62       {
  63         if (errno == EMSGSIZE)
  64         {
  65           return memcached_set_error(*instance, MEMCACHED_WRITE_FAILURE, MEMCACHED_AT);
  66         }
  67
  68         perror(__func__);
  69         return memcached_set_errno(*instance, errno, MEMCACHED_AT);
  70       }
  71     }
  72
  73     return MEMCACHED_SUCCESS;
  74   }
  75
  76   ssize_t sent_length= memcached_io_writev(instance, vector, count, with_flush);
  77   size_t command_length= 0;
  78   for (uint32_t x= 0; x < count; ++x, vector++)
  79   {
  80     command_length+= vector->length;
  81   }
  82
  83   if (sent_length == -1 or size_t(sent_length) != command_length)
  84   {
  85     rc= MEMCACHED_WRITE_FAILURE;
  86     WATCHPOINT_ERROR(rc);
  87     WATCHPOINT_ERRNO(errno);
  88   }
  89   else if (memcached_is_replying(instance->root))
  90   {
  91     memcached_server_response_increment(instance);
  92   }
  93
  94   return rc;
  95 }