developer.intra2net.com Git - libt2n/blob - src/socket_wrapper.cpp

   1 /***************************************************************************
   2  *   Copyright (C) 2008 by Gerd v. Egidy                                   *
   3  *   gve@intra2net.com                                                     *
   4  *                                                                         *
   5  *   This library is free software; you can redistribute it and/or modify  *
   6  *   it under the terms of the GNU Lesser General Public License version   *
   7  *   2.1 as published by the Free Software Foundation.                     *
   8  *                                                                         *
   9  *   This library is distributed in the hope that it will be useful,       *
  10  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  11  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  12  *   GNU Lesser General Public License for more details.                   *
  13  *                                                                         *
  14  *   You should have received a copy of the GNU Lesser General Public      *
  15  *   License along with this program; if not, write to the                 *
  16  *   Free Software Foundation, Inc.,                                       *
  17  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
  18  ***************************************************************************/
  19
  20 #include <functional>
  21 #include <string>
  22
  23 #include <socket_wrapper.hxx>
  24
  25 namespace libt2n
  26 {
  27
  28 /// set logging for coming and current connections
  29 void BasicSocketWrapper::set_logging(std::ostream *_logstream, log_level_values _log_level)
  30 {
  31     ConnectionWrapper::set_logging(_logstream,_log_level);
  32
  33     if (connection_established())
  34         get_connection()->set_logging(_logstream,_log_level);
  35 }
  36
  37
  38 /// return active connection, create new tcp or unix connection if not existing
  39 client_connection* BasicSocketWrapper::get_connection(void)
  40 {
  41     if (c.get() == NULL)
  42     {
  43         if (socket_type == tcp_s)
  44             c=std::auto_ptr<socket_client_connection>
  45                 (new socket_client_connection(port,server,connect_timeout_usec,max_retries,logstream,log_level));
  46         else if (socket_type == unix_s)
  47             c=std::auto_ptr<socket_client_connection>
  48                 (new socket_client_connection(path,connect_timeout_usec,max_retries,logstream,log_level));
  49     }
  50
  51     return c.get();
  52 }
  53
  54 /// try to reconnect max_retries time if we encounter a t2n_communication_error
  55 /// during execution of the command
  56 bool ReconnectSocketWrapper::handle(command_client* stubBase, boost::function< void() > f)
  57 {
  58     int tries=0;
  59
  60     while(true)
  61     {
  62         try
  63         {
  64             // we always reconnect if something went wrong before:
  65             // makes sure the buffers are clean of half-sent packets etc.
  66             if (tries > 0)
  67                 c->reconnect();
  68
  69             f();
  70             // we were successful
  71             return true;
  72         }
  73         catch(t2n_connect_error &e)
  74         {
  75             // reconnect already tries max_tries times to reconnect: we are done if that failed
  76             throw(e);
  77         }
  78         catch(t2n_communication_error &e)
  79         {
  80             // aborts the loop with an exception after max_retries iterations
  81             // retries means that the first try doesn't count: use >
  82             if (tries > max_retries)
  83                 throw(e);
  84
  85             // otherwise ignore the exception and reconnect in the next iteration
  86         }
  87         catch(...)
  88         {
  89             throw;
  90         }
  91
  92         tries++;
  93     }
  94
  95     return false;
  96 }
  97
  98 /// return active connection, return a dummy-connection if we can't establish one
  99 client_connection* ReconnectIgnoreFailureSocketWrapper::get_connection(void)
 100 {
 101     client_connection* tmp=BasicSocketWrapper::get_connection();
 102
 103     if (tmp->is_closed())
 104     {
 105         // throw away the closed connection...
 106         c.reset();
 107         // ...return the dummy one instead
 108         tmp=&dc;
 109     }
 110
 111     return tmp;
 112 }
 113
 114 /// try to execute the command, may ignore the command if server not available
 115 bool ReconnectIgnoreFailureSocketWrapper::handle(command_client* stubBase, boost::function< void() > f)
 116 {
 117     if (!connection_established())
 118     {
 119         // dummy connection is in place: try to establish a real one
 120         client_connection* tmp=get_connection();
 121
 122         if (tmp != &dc)
 123         {
 124             // success! we've got a real connection
 125             stubBase->replace_connection(tmp);
 126         }
 127     }
 128
 129     // only try to handle the call if we've got a real connection
 130     if (connection_established())
 131     {
 132         try
 133         {
 134             ReconnectSocketWrapper::handle(stubBase,f);
 135             return true;
 136         }
 137         catch(t2n_communication_error &e)
 138         {
 139             // ignore
 140         }
 141         catch(...)
 142         {
 143             throw;
 144         }
 145     }
 146
 147     return false;
 148 }
 149
 150 }