| 1 | /*************************************************************************** |
| 2 | * Copyright (C) 2006 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 <string> |
| 21 | #include <sstream> |
| 22 | |
| 23 | #include <boost/archive/binary_oarchive.hpp> |
| 24 | #include <boost/archive/binary_iarchive.hpp> |
| 25 | #include <boost/archive/xml_oarchive.hpp> |
| 26 | #include <boost/archive/xml_iarchive.hpp> |
| 27 | #include <boost/serialization/serialization.hpp> |
| 28 | |
| 29 | #include <boost/bind.hpp> |
| 30 | |
| 31 | #include "command_client.hxx" |
| 32 | |
| 33 | #ifdef HAVE_CONFIG_H |
| 34 | #include <config.h> |
| 35 | #endif |
| 36 | |
| 37 | using namespace std; |
| 38 | |
| 39 | namespace libt2n |
| 40 | { |
| 41 | |
| 42 | command_client::command_client(client_connection* _c, long long _command_timeout_usec, long long _hello_timeout_usec) |
| 43 | : c(_c) |
| 44 | { |
| 45 | command_timeout_usec=_command_timeout_usec; |
| 46 | hello_timeout_usec=_hello_timeout_usec; |
| 47 | |
| 48 | // for reconnects |
| 49 | c->add_callback(new_connection,bind(&command_client::read_hello, boost::ref(*this))); |
| 50 | |
| 51 | // don't expect hello from an always closed connection (like dummy_client_connection) |
| 52 | if (!is_connection_closed()) |
| 53 | { |
| 54 | try |
| 55 | { |
| 56 | read_hello(); |
| 57 | } |
| 58 | catch (t2n_communication_error &e) |
| 59 | { |
| 60 | c->close(); |
| 61 | |
| 62 | // store a copy of the exception that you can find out details about the error later |
| 63 | std::auto_ptr<t2n_exception> tmp(e.clone()); |
| 64 | constructorException=tmp; |
| 65 | } |
| 66 | catch (...) |
| 67 | { |
| 68 | throw; |
| 69 | } |
| 70 | } |
| 71 | } |
| 72 | |
| 73 | /** @brief replace the connection currently in use with a new one |
| 74 | @param _c pointer to the new connection |
| 75 | |
| 76 | @note the old connection must still be valid when this method is called, |
| 77 | it can safely be deleted after this method returned |
| 78 | |
| 79 | @note all callbacks registered on the old connection will be copied over |
| 80 | to the new one |
| 81 | */ |
| 82 | void command_client::replace_connection(client_connection* _c) |
| 83 | { |
| 84 | // copy all callbacks registered on the old connection |
| 85 | for(callback_event_type e=static_cast<callback_event_type>(0); |
| 86 | e < __events_end; |
| 87 | e=static_cast<callback_event_type>(static_cast<int>(e)+1)) |
| 88 | { |
| 89 | list<boost::function<void ()> > evcb=c->get_callback_list(e); |
| 90 | |
| 91 | for (list<boost::function<void ()> >::iterator i=evcb.begin(); i != evcb.end(); i++) |
| 92 | _c->add_callback(e,*i); |
| 93 | } |
| 94 | |
| 95 | // replace the connection |
| 96 | c=_c; |
| 97 | |
| 98 | read_hello(); |
| 99 | } |
| 100 | |
| 101 | /** @brief return a complete packet |
| 102 | @param usec_timeout maximum microseconds to wait until the packet is complete |
| 103 | @retval packet data as std::string |
| 104 | |
| 105 | @note throws a t2n_transfer_error if the timeout is exceeded |
| 106 | */ |
| 107 | std::string command_client::read_packet(const long long &usec_timeout) |
| 108 | { |
| 109 | string resultpacket; |
| 110 | bool got_packet=false; |
| 111 | long long my_timeout=usec_timeout; |
| 112 | while(!(got_packet=c->get_packet(resultpacket)) && my_timeout > 0 && !c->is_closed()) |
| 113 | c->fill_buffer(my_timeout,&my_timeout); |
| 114 | |
| 115 | if (!got_packet) |
| 116 | throw t2n_transfer_error("timeout exceeded"); |
| 117 | |
| 118 | return resultpacket; |
| 119 | } |
| 120 | |
| 121 | /** @brief read and check the hello message at the beginning of a connection |
| 122 | |
| 123 | @note throws exceptions if something went wrong |
| 124 | */ |
| 125 | void command_client::read_hello() |
| 126 | { |
| 127 | string resultpacket; |
| 128 | bool got_packet=false; |
| 129 | long long my_timeout=hello_timeout_usec; |
| 130 | while(!(got_packet=c->get_packet(resultpacket)) && my_timeout > 0 && !c->is_closed()) |
| 131 | { |
| 132 | c->fill_buffer(my_timeout,&my_timeout); |
| 133 | |
| 134 | c->peek_packet(resultpacket); |
| 135 | check_hello(resultpacket); // will throw before timeout if wrong data received |
| 136 | } |
| 137 | |
| 138 | if (!got_packet) |
| 139 | throw t2n_transfer_error("timeout exceeded"); |
| 140 | |
| 141 | if (!check_hello(resultpacket)) |
| 142 | throw t2n_version_mismatch("illegal hello received (incomplete): "+resultpacket); |
| 143 | } |
| 144 | |
| 145 | /** @brief check if a hello message is valid |
| 146 | @param hellostr std::string with the message to check |
| 147 | @retval true if the hello is good and complete |
| 148 | |
| 149 | @note you can check incomplete hellos. you will get a false return value |
| 150 | but no exception. throws exceptions as soon as something is wrong. |
| 151 | */ |
| 152 | bool command_client::check_hello(const std::string& hellostr) |
| 153 | { |
| 154 | istringstream hello(hellostr); |
| 155 | |
| 156 | char chk; |
| 157 | |
| 158 | if (hello.read(&chk,1)) |
| 159 | { |
| 160 | if (chk != 'T') |
| 161 | throw t2n_version_mismatch("illegal hello received (T2N)"); |
| 162 | } |
| 163 | else |
| 164 | return false; |
| 165 | |
| 166 | if (hello.read(&chk,1)) |
| 167 | { |
| 168 | if (chk != '2') |
| 169 | throw t2n_version_mismatch("illegal hello received (T2N)"); |
| 170 | } |
| 171 | else |
| 172 | return false; |
| 173 | |
| 174 | if (hello.read(&chk,1)) |
| 175 | { |
| 176 | if (chk != 'N') |
| 177 | throw t2n_version_mismatch("illegal hello received (T2N)"); |
| 178 | } |
| 179 | else |
| 180 | return false; |
| 181 | |
| 182 | if (hello.read(&chk,1)) |
| 183 | { |
| 184 | if (chk != 'v') |
| 185 | throw t2n_version_mismatch("illegal hello received (T2N)"); |
| 186 | } |
| 187 | else |
| 188 | return false; |
| 189 | |
| 190 | int prot_version; |
| 191 | if (hello >> prot_version) |
| 192 | { |
| 193 | if (prot_version != PROTOCOL_VERSION) |
| 194 | throw t2n_version_mismatch("not compatible with the server protocol version"); |
| 195 | } |
| 196 | else |
| 197 | return false; |
| 198 | |
| 199 | if (hello.read(&chk,1)) |
| 200 | { |
| 201 | if (chk != ';') |
| 202 | throw t2n_version_mismatch("illegal hello received (1. ;)"); |
| 203 | } |
| 204 | else |
| 205 | return false; |
| 206 | |
| 207 | unsigned int hbo; |
| 208 | if (hello.read((char*)&hbo,sizeof(hbo))) |
| 209 | { |
| 210 | if (hbo != 1) |
| 211 | throw t2n_version_mismatch("host byte order not matching"); |
| 212 | } |
| 213 | else |
| 214 | return false; |
| 215 | |
| 216 | if (hello.read(&chk,1)) |
| 217 | { |
| 218 | if (chk != ';') |
| 219 | throw t2n_version_mismatch("illegal hello received (2. ;)"); |
| 220 | } |
| 221 | else |
| 222 | return false; |
| 223 | |
| 224 | return true; |
| 225 | } |
| 226 | |
| 227 | /** @brief send a command to the server and store the result |
| 228 | @param cmd pointer to a command-object |
| 229 | @param[out] res result container to store the result in |
| 230 | |
| 231 | @note you can check incomplete hellos. you will get a false return value |
| 232 | but no exception. throws exceptions as soon as something is wrong. |
| 233 | */ |
| 234 | void command_client::send_command(command* cmd, result_container &res) |
| 235 | { |
| 236 | ostringstream ofs; |
| 237 | command_container cc(cmd); |
| 238 | boost::archive::binary_oarchive oa(ofs); |
| 239 | |
| 240 | if (is_connection_closed()) |
| 241 | throw t2n_transfer_error("connection to server is closed"); |
| 242 | |
| 243 | try |
| 244 | { |
| 245 | oa << cc; |
| 246 | } |
| 247 | catch(boost::archive::archive_exception &e) |
| 248 | { |
| 249 | ostringstream msg; |
| 250 | msg << "archive_exception while serializing on client-side, code " << e.code << " (" << e.what() << ")"; |
| 251 | throw t2n_serialization_error(msg.str()); |
| 252 | } |
| 253 | catch(...) |
| 254 | { throw; } |
| 255 | |
| 256 | std::ostream* ostr; |
| 257 | if ((ostr=c->get_logstream(fulldebug))!=NULL) |
| 258 | { |
| 259 | (*ostr) << "sending command, decoded data: " << std::endl; |
| 260 | boost::archive::xml_oarchive xo(*ostr); |
| 261 | xo << BOOST_SERIALIZATION_NVP(cc); |
| 262 | } |
| 263 | |
| 264 | c->write(ofs.str()); |
| 265 | |
| 266 | istringstream ifs(read_packet(command_timeout_usec)); |
| 267 | boost::archive::binary_iarchive ia(ifs); |
| 268 | |
| 269 | try |
| 270 | { |
| 271 | ia >> res; |
| 272 | } |
| 273 | catch(boost::archive::archive_exception &e) |
| 274 | { |
| 275 | ostringstream msg; |
| 276 | msg << "archive_exception while deserializing on client-side, code " << e.code << " (" << e.what() << ")"; |
| 277 | throw t2n_serialization_error(msg.str()); |
| 278 | } |
| 279 | catch(...) |
| 280 | { throw; } |
| 281 | |
| 282 | if ((ostr=c->get_logstream(fulldebug))!=NULL) |
| 283 | { |
| 284 | (*ostr) << "received result, decoded data: " << std::endl; |
| 285 | boost::archive::xml_oarchive xo(*ostr); |
| 286 | xo << BOOST_SERIALIZATION_NVP(res); |
| 287 | } |
| 288 | } |
| 289 | |
| 290 | } |