Line data    Source code

       1             : // Copyright (c) 2012-2019  Made to Order Software Corp.  All Rights Reserved
       2             : //
       3             : // https://snapwebsites.org/project/eventdispatcher
       4             : // contact@m2osw.com
       5             : //
       6             : // This program is free software; you can redistribute it and/or modify
       7             : // it under the terms of the GNU General Public License as published by
       8             : // the Free Software Foundation; either version 2 of the License, or
       9             : // (at your option) any later version.
      10             : //
      11             : // This program is distributed in the hope that it will be useful,
      12             : // but WITHOUT ANY WARRANTY; without even the implied warranty of
      13             : // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      14             : // GNU General Public License for more details.
      15             : //
      16             : // You should have received a copy of the GNU General Public License
      17             : // along with this program; if not, write to the Free Software
      18             : // Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
      19             : 
      20             : /** \file
      21             :  * \brief Event dispatch class.
      22             :  *
      23             :  * Class used to handle events.
      24             :  */
      25             : 
      26             : 
      27             : // self
      28             : //
      29             : #include    "eventdispatcher/udp_client.h"
      30             : 
      31             : 
      32             : // last include
      33             : //
      34             : #include    <snapdev/poison.h>
      35             : 
      36             : 
      37             : 
      38             : namespace ed
      39             : {
      40             : 
      41             : 
      42             : 
      43             : /** \brief Initialize a UDP client object.
      44             :  *
      45             :  * This function initializes the UDP client object using the address and the
      46             :  * port as specified.
      47             :  *
      48             :  * The port is expected to be a host side port number (i.e. 59200).
      49             :  *
      50             :  * The \p addr parameter is a textual address. It may be an IPv4 or IPv6
      51             :  * address and it can represent a host name or an address defined with
      52             :  * just numbers. If the address cannot be resolved then an error occurs
      53             :  * and constructor throws.
      54             :  *
      55             :  * \note
      56             :  * The socket is open in this process. If you fork() or exec() then the
      57             :  * socket will be closed by the operating system.
      58             :  *
      59             :  * \warning
      60             :  * We only make use of the first address found by getaddrinfo(). All
      61             :  * the other addresses are ignored.
      62             :  *
      63             :  * \exception udp_client_server_runtime_error
      64             :  * The server could not be initialized properly. Either the address cannot be
      65             :  * resolved, the port is incompatible or not available, or the socket could
      66             :  * not be created.
      67             :  *
      68             :  * \param[in] addr  The address to convert to a numeric IP.
      69             :  * \param[in] port  The port number.
      70             :  * \param[in] family  The family used to search for 'addr'.
      71             :  */
      72           0 : udp_client::udp_client(std::string const & addr, int port, int family)
      73           0 :     : udp_base(addr, port, family)
      74             : {
      75           0 : }
      76             : 
      77             : 
      78             : /** \brief Clean up the UDP client object.
      79             :  *
      80             :  * This function frees the address information structure and close the socket
      81             :  * before returning.
      82             :  */
      83           0 : udp_client::~udp_client()
      84             : {
      85           0 : }
      86             : 
      87             : 
      88             : /** \brief Send a message through this UDP client.
      89             :  *
      90             :  * This function sends \p msg through the UDP client socket. The function
      91             :  * cannot be used to change the destination as it was defined when creating
      92             :  * the udp_client object.
      93             :  *
      94             :  * The size must be small enough for the message to fit. In most cases we
      95             :  * use these in Snap! to send very small signals (i.e. 4 bytes commands.)
      96             :  * Any data we would want to share remains in the Cassandra database so
      97             :  * that way we can avoid losing it because of a UDP message.
      98             :  *
      99             :  * \param[in] msg  The message to send.
     100             :  * \param[in] size  The number of bytes representing this message.
     101             :  *
     102             :  * \return -1 if an error occurs, otherwise the number of bytes sent. errno
     103             :  * is set accordingly on error.
     104             :  */
     105           0 : int udp_client::send(char const * msg, size_t size)
     106             : {
     107           0 :     return static_cast<int>(sendto(f_socket.get(), msg, size, 0, f_addrinfo->ai_addr, f_addrinfo->ai_addrlen));
     108             : }
     109             : 
     110             : 
     111             : 
     112           6 : } // namespace ed
     113             : // vim: ts=4 sw=4 et