Function net_write_command

sql/net_serv.cc:483–542

*/

my_bool
net_write_command(NET *net,uchar command,
		  const uchar *header, size_t head_len,
		  const uchar *packet, size_t len)
{
  size_t length=len+1+head_len;			/* 1 extra byte for command */
  uchar buff[NET_HEADER_SIZE+1];
  uint header_size=NET_HEADER_SIZE+1;
  my_bool rc;
  DBUG_ENTER("net_write_command");
  DBUG_PRINT("enter",("length: %lu", (ulong) len));

#ifdef ENABLED_DEBUG_SYNC
  DBUG_EXECUTE_IF("simulate_error_on_packet_write",
                  {
                    if (command == COM_BINLOG_DUMP)
                    {
                      net->last_errno = ER_NET_ERROR_ON_WRITE;
                      DBUG_ASSERT(!debug_sync_set_action(
                      (THD *)net->thd,
                      STRING_WITH_LEN("now SIGNAL parked WAIT_FOR continue")));
                      DBUG_RETURN(true);
                    }
                  };);
#endif
  MYSQL_NET_WRITE_START(length);

  buff[4]=command;				/* For first packet */

  if (length >= MAX_PACKET_LENGTH)
  {
    /* Take into account that we have the command in the first header */
    len= MAX_PACKET_LENGTH - 1 - head_len;
    do
    {
      int3store(buff, MAX_PACKET_LENGTH);
      buff[3]= (uchar) net->pkt_nr++;
      if (net_write_buff(net, buff, header_size) ||
	  net_write_buff(net, header, head_len) ||
	  net_write_buff(net, packet, len))
      {
        MYSQL_NET_WRITE_DONE(1);
	DBUG_RETURN(1);
      }
      packet+= len;
      length-= MAX_PACKET_LENGTH;
      len= MAX_PACKET_LENGTH;
      head_len= 0;
      header_size= NET_HEADER_SIZE;
    } while (length >= MAX_PACKET_LENGTH);
    len=length;					/* Data left to be written */
  }
  int3store(buff,length);
  buff[3]= (uchar) net->pkt_nr++;
  rc= MY_TEST(net_write_buff(net, buff, header_size) ||
              (head_len && net_write_buff(net, header, head_len)) ||
              net_write_buff(net, packet, len) || net_flush(net));
  MYSQL_NET_WRITE_DONE(rc);