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

   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 #ifndef __LIBT2N_SOCKET_WRAPPER
  21 #define __LIBT2N_SOCKET_WRAPPER
  22
  23 #include <functional>
  24 #include <string>
  25
  26 #include <client.hxx>
  27 #include <command_client.hxx>
  28 #include <types.hxx>
  29 #include <client_wrapper.hxx>
  30 #include <socket_client.hxx>
  31
  32 namespace libt2n
  33 {
  34
  35 /** @brief a basic implementation of ConnectionWrapper
  36
  37     This is a basic version of a ConnectionWrapper which does not do any fancy
  38     error handling or anything, it justs executes the regular calls. Use this
  39     wrapper if you only want to use the singleton-feature of T2nSingletonWrapper.
  40 */
  41 class BasicSocketWrapper : public ConnectionWrapper
  42 {
  43     protected:
  44         socket_type_value socket_type;
  45
  46         std::string path;
  47         std::string server;
  48         int port;
  49
  50         long long connect_timeout_usec;
  51         int max_retries;
  52
  53         std::auto_ptr<socket_client_connection> c;
  54
  55         // TODO: Mark object as non-copyable as it contains an auto_ptr.
  56         //       This will make sure nobody every tries to put this in a STL container
  57
  58     public:
  59         BasicSocketWrapper(int _port, const std::string& _server="127.0.0.1",
  60             long long _connect_timeout_usec=socket_client_connection::connect_timeout_usec_default,
  61             int _max_retries=socket_client_connection::max_retries_default)
  62             : port(_port), server(_server), connect_timeout_usec(_connect_timeout_usec),
  63               max_retries(_max_retries), socket_type(tcp_s), ConnectionWrapper()
  64             { }
  65
  66         BasicSocketWrapper(const std::string& _path,
  67             long long _connect_timeout_usec=socket_client_connection::connect_timeout_usec_default,
  68             int _max_retries=socket_client_connection::max_retries_default)
  69             : path(_path), connect_timeout_usec(_connect_timeout_usec),
  70               max_retries(_max_retries), socket_type(unix_s), ConnectionWrapper()
  71             { }
  72
  73         client_connection* get_connection(void);
  74
  75         bool connection_established(void)
  76             { return (c.get() != NULL); }
  77
  78         void set_logging(std::ostream *_logstream, log_level_values _log_level);
  79 };
  80
  81 /** @brief a wrapper implementing reconnect-then-throw
  82
  83     This ConnectionWrapper tries to reconnect to the server if something with the connection
  84     goes wrong. If even reconnecting max_retries times does not help, an exception is thrown.
  85 */
  86 class ReconnectSocketWrapper : public BasicSocketWrapper
  87 {
  88     public:
  89         ReconnectSocketWrapper(int _port, const std::string& _server="127.0.0.1",
  90             long long _connect_timeout_usec=socket_client_connection::connect_timeout_usec_default,
  91             int _max_retries=socket_client_connection::max_retries_default)
  92             : BasicSocketWrapper(_port,_server,_connect_timeout_usec,_max_retries)
  93             { }
  94
  95         ReconnectSocketWrapper(const std::string& _path,
  96             long long _connect_timeout_usec=socket_client_connection::connect_timeout_usec_default,
  97             int _max_retries=socket_client_connection::max_retries_default)
  98             : BasicSocketWrapper(_path,_connect_timeout_usec,_max_retries)
  99             { }
 100
 101         bool handle(command_client* stubBase, boost::function< void() > f);
 102 };
 103
 104 /// a placeholder-client_connection which is closed all the time
 105 class dummy_client_connection : public client_connection
 106 {
 107     private:
 108         void real_write(const std::string& data)
 109             { }
 110
 111     public:
 112         dummy_client_connection()
 113             : client_connection()
 114             { close(); }
 115
 116         bool fill_buffer(long long usec_timeout=-1, long long *usec_timeout_remaining=NULL)
 117             { return false; }
 118 };
 119
 120 /** @brief a wrapper implementing reconnect-then-ignore
 121
 122     This ConnectionWrapper tries to reconnect to the server if something with the connection
 123     goes wrong. If even reconnecting max_retries times does not help, the complete t2n-call is
 124     ignored. The return value of the call will be created with the default constructor.
 125 */
 126 class ReconnectIgnoreFailureSocketWrapper : public ReconnectSocketWrapper
 127 {
 128     private:
 129         dummy_client_connection dc;
 130
 131     public:
 132         ReconnectIgnoreFailureSocketWrapper(int _port, const std::string& _server="127.0.0.1",
 133             long long _connect_timeout_usec=socket_client_connection::connect_timeout_usec_default,
 134             int _max_retries=socket_client_connection::max_retries_default)
 135             : ReconnectSocketWrapper(_port,_server,_connect_timeout_usec,_max_retries)
 136             { }
 137
 138         ReconnectIgnoreFailureSocketWrapper(const std::string& _path,
 139             long long _connect_timeout_usec=socket_client_connection::connect_timeout_usec_default,
 140             int _max_retries=socket_client_connection::max_retries_default)
 141             : ReconnectSocketWrapper(_path,_connect_timeout_usec,_max_retries)
 142             { }
 143
 144         client_connection* get_connection(void);
 145         bool handle(command_client* stubBase, boost::function< void() > f);
 146 };
 147
 148 }
 149
 150 #endif