| 1 | /*************************************************************************** |
| 2 | * Copyright (C) 2008 by Gerd v. Egidy and Reinhard Pfau * |
| 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 | #ifndef __LIBT2N_CLIENT_WRAPPER |
| 20 | #define __LIBT2N_CLIENT_WRAPPER |
| 21 | |
| 22 | #include <functional> |
| 23 | |
| 24 | #include <boost/config.hpp> |
| 25 | #include <boost/any.hpp> |
| 26 | #include <boost/bind.hpp> |
| 27 | #include <boost/function.hpp> |
| 28 | #include <boost/preprocessor.hpp> |
| 29 | |
| 30 | #include <client.hxx> |
| 31 | #include <command_client.hxx> |
| 32 | |
| 33 | #ifndef T2NWRAPPER_MAX_ARGS |
| 34 | #define T2NWRAPPER_MAX_ARGS 9 |
| 35 | #endif |
| 36 | |
| 37 | namespace libt2n |
| 38 | { |
| 39 | |
| 40 | class ConnectionInitData |
| 41 | { |
| 42 | public: |
| 43 | |
| 44 | virtual std::auto_ptr<client_connection> createConnection()=0; |
| 45 | |
| 46 | virtual ~ConnectionInitData() |
| 47 | { } |
| 48 | }; |
| 49 | |
| 50 | class TrivialHandler |
| 51 | { |
| 52 | public: |
| 53 | static void handle( boost::function< void() > f) |
| 54 | { |
| 55 | f(); |
| 56 | } |
| 57 | }; |
| 58 | |
| 59 | // contains the internal stuff needed for T2nWrapper |
| 60 | namespace detail |
| 61 | { |
| 62 | |
| 63 | template< typename T > |
| 64 | struct TypeWrap |
| 65 | { |
| 66 | typedef T type; |
| 67 | }; |
| 68 | |
| 69 | template< > |
| 70 | struct TypeWrap< void > |
| 71 | { |
| 72 | typedef int type; |
| 73 | }; |
| 74 | |
| 75 | template< typename R > |
| 76 | struct Call |
| 77 | { |
| 78 | typedef boost::function< R() > FuncType; |
| 79 | |
| 80 | FuncType function; |
| 81 | R& result; |
| 82 | |
| 83 | Call( FuncType f, R& res ) : function(f), result( res ) {} |
| 84 | |
| 85 | void operator()() |
| 86 | { |
| 87 | result= function(); |
| 88 | } |
| 89 | }; |
| 90 | |
| 91 | template< > |
| 92 | struct Call<void> |
| 93 | { |
| 94 | typedef boost::function< void() > FuncType; |
| 95 | typedef TypeWrap< void >::type ResultType; |
| 96 | |
| 97 | FuncType function; |
| 98 | ResultType& result; |
| 99 | |
| 100 | Call( FuncType f, ResultType& res ) : function(f), result( res ) {} |
| 101 | |
| 102 | void operator()() |
| 103 | { |
| 104 | function(); |
| 105 | result= ResultType(); |
| 106 | } |
| 107 | }; |
| 108 | } // eo namespace detail |
| 109 | |
| 110 | template< |
| 111 | class Client, |
| 112 | class Handler = TrivialHandler |
| 113 | > |
| 114 | class T2nWrapper |
| 115 | { |
| 116 | private: |
| 117 | |
| 118 | std::auto_ptr<client_connection> conndConn; |
| 119 | std::auto_ptr<Client> client; |
| 120 | |
| 121 | static std::auto_ptr<T2nWrapper> singletonObject; |
| 122 | static std::auto_ptr<ConnectionInitData> initData; |
| 123 | |
| 124 | // create a prep-method for each possible number of parameters |
| 125 | #define _GEN_ARG(z,n,d) Arg ## n arg ##n |
| 126 | #define _GEN_PREP(z,n,d) \ |
| 127 | template< typename R BOOST_PP_COMMA_IF(n) BOOST_PP_ENUM_PARAMS(n,typename Arg) > \ |
| 128 | static boost::function< R(Client*) > prep \ |
| 129 | ( \ |
| 130 | R(Client::*f)( BOOST_PP_ENUM_PARAMS(n,Arg) ) \ |
| 131 | BOOST_PP_COMMA_IF(n) \ |
| 132 | BOOST_PP_ENUM( n, _GEN_ARG, ~ ) \ |
| 133 | ) \ |
| 134 | { \ |
| 135 | return boost::bind< R > \ |
| 136 | ( \ |
| 137 | f, _1 BOOST_PP_COMMA_IF(n) BOOST_PP_ENUM_PARAMS(n,arg) \ |
| 138 | ); \ |
| 139 | } // eo prep |
| 140 | |
| 141 | BOOST_PP_REPEAT( BOOST_PP_ADD(T2NWRAPPER_MAX_ARGS,1) , _GEN_PREP, ~ ) |
| 142 | |
| 143 | #undef _GEN_PREP |
| 144 | #undef _GEN_ARG |
| 145 | |
| 146 | static void ensureSingletonThere(void) |
| 147 | { |
| 148 | if (singletonObject.get() == NULL) |
| 149 | { |
| 150 | // we need to initialize |
| 151 | |
| 152 | if (initData.get() == NULL) |
| 153 | throw std::logic_error("T2nWrapper singleton used before setting initData"); |
| 154 | |
| 155 | std::auto_ptr<client_connection> myConndConn=initData->createConnection(); |
| 156 | |
| 157 | } |
| 158 | } |
| 159 | |
| 160 | template< typename R > |
| 161 | static |
| 162 | typename detail::TypeWrap<R>::type real_exec( boost::function< R(Client*) > f) |
| 163 | { |
| 164 | ensureSingletonThere(); |
| 165 | |
| 166 | typename detail::TypeWrap<R>::type result; |
| 167 | detail::Call<R> call( boost::bind( f, &(*(singletonObject->client))), result ); |
| 168 | Handler::handle( call ); |
| 169 | return result; |
| 170 | } |
| 171 | |
| 172 | public: |
| 173 | |
| 174 | static void setInitData(std::auto_ptr<ConnectionInitData> newInitData) |
| 175 | { initData=newInitData; } |
| 176 | static ConnectionInitData* getInitData(void) |
| 177 | { return initData.get(); } |
| 178 | |
| 179 | T2nWrapper() |
| 180 | { |
| 181 | client=std::auto_ptr<Client>(new Client(*conndConn)); |
| 182 | } |
| 183 | |
| 184 | // create an exec-method for each possible number of parameters |
| 185 | #define _GEN_PLACEHOLDER(z,n,d) BOOST_PP_CAT(_,BOOST_PP_ADD(n,1)) |
| 186 | #define _GEN_EXEC(z,n,d) \ |
| 187 | template< typename R BOOST_PP_COMMA_IF(n) BOOST_PP_ENUM_PARAMS(n,typename Arg) > \ |
| 188 | static boost::function< R( BOOST_PP_ENUM_PARAMS(n,Arg) ) > exec \ |
| 189 | ( \ |
| 190 | R(Client::*f)( BOOST_PP_ENUM_PARAMS(n,Arg) ) \ |
| 191 | ) \ |
| 192 | { \ |
| 193 | boost::function<R(Client*)>(*p)(R(Client::*)( BOOST_PP_ENUM_PARAMS(n,Arg) ) \ |
| 194 | BOOST_PP_COMMA_IF(n) BOOST_PP_ENUM_PARAMS(n,Arg)) \ |
| 195 | = &T2nWrapper::template prep<R BOOST_PP_COMMA_IF(n) BOOST_PP_ENUM_PARAMS(n,Arg) >; \ |
| 196 | return boost::bind \ |
| 197 | ( \ |
| 198 | T2nWrapper::template real_exec<R>, \ |
| 199 | boost::bind( p, f BOOST_PP_COMMA_IF(n) \ |
| 200 | BOOST_PP_ENUM(n, _GEN_PLACEHOLDER, ~ ) ) \ |
| 201 | ); \ |
| 202 | } // eo exec |
| 203 | |
| 204 | BOOST_PP_REPEAT( BOOST_PP_ADD(T2NWRAPPER_MAX_ARGS,1), _GEN_EXEC, ~ ) |
| 205 | |
| 206 | #undef _GEN_EXEC |
| 207 | #undef _GEN_PLACEHOLDER |
| 208 | |
| 209 | }; |
| 210 | |
| 211 | } |
| 212 | #endif |