| 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 <stdio.h> |
| 21 | #include <errno.h> |
| 22 | #include <stdlib.h> |
| 23 | #include <unistd.h> |
| 24 | #include <sys/types.h> |
| 25 | #include <sys/socket.h> |
| 26 | #include <sys/un.h> |
| 27 | #include <sys/time.h> |
| 28 | #include <arpa/inet.h> |
| 29 | #include <netinet/in.h> |
| 30 | #include <netdb.h> |
| 31 | #include <fcntl.h> |
| 32 | #include <time.h> |
| 33 | #include <pwd.h> |
| 34 | #include <grp.h> |
| 35 | |
| 36 | #include <sstream> |
| 37 | |
| 38 | #include "socket_server.hxx" |
| 39 | #include "t2n_exception.hxx" |
| 40 | |
| 41 | using namespace std; |
| 42 | |
| 43 | namespace libt2n |
| 44 | { |
| 45 | |
| 46 | socket_server::socket_server(int port, const char* ip) |
| 47 | : server() |
| 48 | { |
| 49 | socket_type=tcp_s; |
| 50 | |
| 51 | } |
| 52 | |
| 53 | socket_server::socket_server(const char* path, mode_t filemode, const char* user, const char* group) |
| 54 | : server() |
| 55 | { |
| 56 | socket_type=unix_s; |
| 57 | unix_path=path; |
| 58 | |
| 59 | /* Create the socket. */ |
| 60 | sock = socket (PF_UNIX, SOCK_STREAM, 0); |
| 61 | if (sock < 0) |
| 62 | { |
| 63 | string err="error opening socket: "; |
| 64 | err+=strerror(errno); |
| 65 | log(error, err); |
| 66 | throw t2n_server_error(err); |
| 67 | } |
| 68 | |
| 69 | set_socket_options(sock); |
| 70 | |
| 71 | /* Give the socket a name. */ |
| 72 | struct sockaddr_un unix_name; |
| 73 | unix_name.sun_family = AF_UNIX; |
| 74 | strncpy (unix_name.sun_path, unix_path.c_str(),sizeof(unix_name.sun_path)); |
| 75 | |
| 76 | /* just to make sure there is no other socket file */ |
| 77 | unlink (unix_name.sun_path); |
| 78 | |
| 79 | if (bind (sock, (struct sockaddr *) &unix_name, sizeof (unix_name)) < 0) |
| 80 | { |
| 81 | string err="error binding socket: "; |
| 82 | err+=strerror(errno); |
| 83 | log(error, err); |
| 84 | throw t2n_server_error(err); |
| 85 | } |
| 86 | |
| 87 | /* change permissions */ |
| 88 | if (chmod (unix_name.sun_path, filemode) != 0) |
| 89 | { |
| 90 | string err="error changing permission: "; |
| 91 | err+=strerror(errno); |
| 92 | log(error, err); |
| 93 | throw t2n_server_error(err); |
| 94 | } |
| 95 | |
| 96 | struct passwd *socket_user = getpwnam (user); |
| 97 | if (socket_user == NULL) |
| 98 | { |
| 99 | string err="error getting socket user: "; |
| 100 | err+=strerror(errno); |
| 101 | log(error, err); |
| 102 | throw t2n_server_error(err); |
| 103 | } |
| 104 | |
| 105 | struct group *socket_group = getgrnam (group); |
| 106 | if (socket_group == NULL) |
| 107 | { |
| 108 | string err="error getting socket group: "; |
| 109 | err+=strerror(errno); |
| 110 | log(error, err); |
| 111 | throw t2n_server_error(err); |
| 112 | } |
| 113 | |
| 114 | if (chown (unix_name.sun_path, socket_user->pw_uid, socket_group->gr_gid) != 0) |
| 115 | { |
| 116 | string err="error changing socket ownership: "; |
| 117 | err+=strerror(errno); |
| 118 | log(error, err); |
| 119 | throw t2n_server_error(err); |
| 120 | } |
| 121 | |
| 122 | if (listen (sock, 5) < 0) |
| 123 | { |
| 124 | string err="error listening to socket: "; |
| 125 | err+=strerror(errno); |
| 126 | log(error, err); |
| 127 | throw t2n_server_error(err); |
| 128 | } |
| 129 | |
| 130 | /* clear & insert server sock into the fd_tab to prepare select */ |
| 131 | FD_ZERO(&connection_set); |
| 132 | FD_SET (sock, &connection_set); |
| 133 | } |
| 134 | |
| 135 | void socket_server::set_socket_options(int sock) |
| 136 | { |
| 137 | int i=1; |
| 138 | |
| 139 | /* fast reuse enable */ |
| 140 | if (setsockopt(sock,SOL_SOCKET, SO_REUSEADDR, &i, sizeof(i)) < 0) |
| 141 | { |
| 142 | string err="error setting socket option: "; |
| 143 | err+=strerror(errno); |
| 144 | log(error, err); |
| 145 | throw t2n_server_error(err); |
| 146 | } |
| 147 | |
| 148 | /* keepalive enable */ |
| 149 | if (setsockopt(sock,SOL_SOCKET, SO_KEEPALIVE, &i, sizeof(i)) < 0) |
| 150 | { |
| 151 | string err="error setting socket option: "; |
| 152 | err+=strerror(errno); |
| 153 | log(error, err); |
| 154 | throw t2n_server_error(err); |
| 155 | } |
| 156 | |
| 157 | /* close on exec */ |
| 158 | int fdflags; |
| 159 | fdflags=fcntl(sock,F_GETFD, 0); |
| 160 | if (fdflags < 0) |
| 161 | { |
| 162 | string err="fcntl error on socket: "; |
| 163 | err+=strerror(errno); |
| 164 | log(error, err); |
| 165 | throw t2n_server_error(err); |
| 166 | } |
| 167 | fdflags |= FD_CLOEXEC; |
| 168 | if (fcntl(sock,F_SETFD,fdflags) < 0) |
| 169 | { |
| 170 | string err="fcntl error on socket: "; |
| 171 | err+=strerror(errno); |
| 172 | log(error, err); |
| 173 | throw t2n_server_error(err); |
| 174 | } |
| 175 | |
| 176 | /* non-blocking mode */ |
| 177 | int flflags; |
| 178 | flflags=fcntl(sock,F_GETFL,0); |
| 179 | if (flflags < 0) |
| 180 | { |
| 181 | string err="fcntl error on socket: "; |
| 182 | err+=strerror(errno); |
| 183 | log(error, err); |
| 184 | throw t2n_server_error(err); |
| 185 | } |
| 186 | flflags |= O_NONBLOCK; |
| 187 | if (fcntl(sock,F_SETFL,flflags) < 0) |
| 188 | { |
| 189 | string err="fcntl error on socket: "; |
| 190 | err+=strerror(errno); |
| 191 | log(error, err); |
| 192 | throw t2n_server_error(err); |
| 193 | } |
| 194 | } |
| 195 | |
| 196 | socket_server::~socket_server() |
| 197 | { |
| 198 | close(sock); |
| 199 | |
| 200 | if (socket_type==unix_s) |
| 201 | unlink(unix_path.c_str()); |
| 202 | } |
| 203 | |
| 204 | void socket_server::new_connection() |
| 205 | { |
| 206 | struct sockaddr_un clientname; |
| 207 | |
| 208 | unsigned int size = sizeof (clientname); |
| 209 | int newsock = accept (sock,(struct sockaddr *) &clientname,&size); |
| 210 | if (newsock < 0) |
| 211 | { |
| 212 | if (errno == EAGAIN) |
| 213 | { |
| 214 | log(error, "accept error (EAGAIN): no connection waiting"); |
| 215 | return; |
| 216 | } |
| 217 | |
| 218 | /* default: break */ |
| 219 | string err="error accepting connection: "; |
| 220 | err+=strerror(errno); |
| 221 | log(error, err); |
| 222 | throw t2n_server_error(err); |
| 223 | } |
| 224 | |
| 225 | FD_SET (newsock, &connection_set); |
| 226 | |
| 227 | int i=1; |
| 228 | |
| 229 | /* keepalive enable */ |
| 230 | if (setsockopt(newsock,SOL_SOCKET, SO_KEEPALIVE, &i, sizeof(i)) < 0) |
| 231 | { |
| 232 | string err="error setting socket option: "; |
| 233 | err+=strerror(errno); |
| 234 | log(error, err); |
| 235 | throw t2n_server_error(err); |
| 236 | } |
| 237 | |
| 238 | /* close on exec */ |
| 239 | int fdflags; |
| 240 | fdflags=fcntl(newsock,F_GETFD, 0); |
| 241 | if (fdflags < 0) |
| 242 | { |
| 243 | string err="fcntl error on socket: "; |
| 244 | err+=strerror(errno); |
| 245 | log(error, err); |
| 246 | throw t2n_server_error(err); |
| 247 | } |
| 248 | fdflags |= FD_CLOEXEC; |
| 249 | if (fcntl(newsock,F_SETFD,fdflags) < 0) |
| 250 | { |
| 251 | string err="fcntl error on socket: "; |
| 252 | err+=strerror(errno); |
| 253 | log(error, err); |
| 254 | throw t2n_server_error(err); |
| 255 | } |
| 256 | |
| 257 | /* non-blocking mode */ |
| 258 | int flflags; |
| 259 | flflags=fcntl(newsock,F_GETFL,0); |
| 260 | if (flflags < 0) |
| 261 | { |
| 262 | string err="fcntl error on socket: "; |
| 263 | err+=strerror(errno); |
| 264 | log(error, err); |
| 265 | throw t2n_server_error(err); |
| 266 | } |
| 267 | flflags |= O_NONBLOCK; |
| 268 | if (fcntl(newsock,F_SETFL,flflags) < 0) |
| 269 | { |
| 270 | string err="fcntl error on socket: "; |
| 271 | err+=strerror(errno); |
| 272 | log(error, err); |
| 273 | throw t2n_server_error(err); |
| 274 | } |
| 275 | |
| 276 | add_connection(new socket_connection(newsock, get_default_timeout())); |
| 277 | |
| 278 | return; |
| 279 | } |
| 280 | |
| 281 | void socket_server::fill_buffer(long long usec_timeout) |
| 282 | { |
| 283 | fd_set used_fdset=connection_set; |
| 284 | |
| 285 | /* set timeout */ |
| 286 | struct timeval tval; |
| 287 | struct timeval *timeout_ptr; |
| 288 | |
| 289 | if (usec_timeout == -1) |
| 290 | timeout_ptr = NULL; |
| 291 | else |
| 292 | { |
| 293 | timeout_ptr = &tval; |
| 294 | |
| 295 | // timeout von long long usec in int sec + int usec umrechnen |
| 296 | tval.tv_sec = usec_timeout / 1000000; |
| 297 | tval.tv_usec = usec_timeout % 1000000; |
| 298 | } |
| 299 | |
| 300 | int ret=select (FD_SETSIZE, &used_fdset, NULL, NULL, timeout_ptr); |
| 301 | |
| 302 | if (ret < 0) |
| 303 | { |
| 304 | if (errno == EINTR) |
| 305 | { |
| 306 | // select interrupted by signal |
| 307 | ret=0; |
| 308 | } |
| 309 | else |
| 310 | { |
| 311 | string err="select error: "; |
| 312 | err+=strerror(errno); |
| 313 | log(error, err); |
| 314 | throw t2n_server_error(err); |
| 315 | } |
| 316 | } |
| 317 | |
| 318 | if (ret > 0) |
| 319 | { |
| 320 | // we have data pending |
| 321 | |
| 322 | // check for new connection |
| 323 | if (FD_ISSET (sock, &used_fdset)) |
| 324 | { |
| 325 | new_connection(); |
| 326 | } |
| 327 | |
| 328 | // check all connections for pending data |
| 329 | fill_connection_buffers(); |
| 330 | } |
| 331 | |
| 332 | return; |
| 333 | } |
| 334 | |
| 335 | void socket_server::fill_connection_buffers() |
| 336 | { |
| 337 | std::map<unsigned int, connection*>::iterator ie=connections.end(); |
| 338 | for(std::map<unsigned int, connection*>::iterator i=connections.begin(); i != ie; i++) |
| 339 | if (!i->second->is_closed()) |
| 340 | { |
| 341 | socket_connection* cp=dynamic_cast<socket_connection*>(i->second); |
| 342 | cp->fill_buffer(connection_set); |
| 343 | } |
| 344 | } |
| 345 | |
| 346 | socket_connection::socket_connection(int _sock, int _timeout) |
| 347 | : connection(_timeout) |
| 348 | { |
| 349 | sock=_sock; |
| 350 | } |
| 351 | |
| 352 | void socket_connection::close() |
| 353 | { |
| 354 | |
| 355 | } |
| 356 | |
| 357 | void socket_connection::fill_buffer(fd_set &cur_fdset) |
| 358 | { |
| 359 | bool try_again=false; |
| 360 | |
| 361 | if (is_closed() || !FD_ISSET (sock, &cur_fdset)) |
| 362 | return; // no data pending or connection closed |
| 363 | |
| 364 | // data pending -> go and get it |
| 365 | char socket_buffer[recv_buffer_size]; |
| 366 | |
| 367 | int nbytes = read (sock, socket_buffer, recv_buffer_size); |
| 368 | if (nbytes < 0) |
| 369 | { |
| 370 | if (errno == EAGAIN) |
| 371 | { |
| 372 | if (my_server) |
| 373 | my_server->log(server::error,"read error: no data (EAGAIN) for connection "+get_id_string()); |
| 374 | return; |
| 375 | } |
| 376 | else if (errno == EINTR) |
| 377 | { |
| 378 | // interrupted, try again |
| 379 | try_again=true; |
| 380 | } |
| 381 | else |
| 382 | { |
| 383 | if (my_server) |
| 384 | my_server->log(server::error,"error reading from socket of connection "+get_id_string()+": "+strerror(errno)); |
| 385 | return; |
| 386 | } |
| 387 | } |
| 388 | |
| 389 | // End-of-file |
| 390 | if (nbytes == 0 && !try_again) |
| 391 | { |
| 392 | close(); |
| 393 | return; |
| 394 | } |
| 395 | |
| 396 | // Data read -> store it |
| 397 | if (nbytes > 0) |
| 398 | buffer.assign(socket_buffer,nbytes); |
| 399 | |
| 400 | // more data waiting? |
| 401 | fd_set active_fd_set; |
| 402 | struct timeval tval; |
| 403 | |
| 404 | FD_ZERO (&active_fd_set); |
| 405 | FD_SET (sock, &active_fd_set); |
| 406 | |
| 407 | /* no waiting */ |
| 408 | tval.tv_sec=0; |
| 409 | tval.tv_usec=0; |
| 410 | |
| 411 | if (select (FD_SETSIZE, &active_fd_set, NULL, NULL, &tval) >0) |
| 412 | { |
| 413 | /* more data waiting -> recurse */ |
| 414 | fill_buffer(active_fd_set); |
| 415 | } |
| 416 | |
| 417 | reset_timeout(); |
| 418 | |
| 419 | return; |
| 420 | } |
| 421 | |
| 422 | void socket_connection::write(const std::string& data) |
| 423 | { |
| 424 | static const unsigned int write_block_size=4096; |
| 425 | |
| 426 | if (is_closed()) |
| 427 | return; |
| 428 | |
| 429 | // prepend packet size to data |
| 430 | packet_size_indicator psize=data.size(); |
| 431 | string send_data(data); |
| 432 | send_data.insert(0,(char*)psize,sizeof(packet_size_indicator)); |
| 433 | |
| 434 | int offset = 0; |
| 435 | while (offset < send_data.size()) |
| 436 | { |
| 437 | unsigned int write_size=write_block_size; |
| 438 | |
| 439 | if (offset+write_size > send_data.size()) |
| 440 | write_size = send_data.size()-offset; |
| 441 | |
| 442 | int rtn; |
| 443 | while ((rtn=::write(sock, send_data.data()+offset, write_size)) && |
| 444 | rtn == -1 && (errno == EAGAIN || errno == EINTR)) |
| 445 | { |
| 446 | usleep (80000); |
| 447 | if (my_server) |
| 448 | my_server->log(server::debug,"resuming write() call after EAGAIN or EINTR for connection "+get_id_string()); |
| 449 | } |
| 450 | |
| 451 | if (rtn == -1) |
| 452 | { |
| 453 | if (my_server) |
| 454 | my_server->log(server::error,"write() error on connection "+get_id_string()+": "+strerror(errno)); |
| 455 | } |
| 456 | else if (rtn != write_size) |
| 457 | { |
| 458 | if (my_server) |
| 459 | { |
| 460 | ostringstream msg; |
| 461 | msg << "write() error on connection " << get_id() |
| 462 | << ": wrote " << rtn << " bytes, should have been " |
| 463 | << write_size << " (complete: " << send_data.size() << ")"; |
| 464 | |
| 465 | my_server->log(server::error,msg.str()); |
| 466 | } |
| 467 | } |
| 468 | |
| 469 | offset += write_size; |
| 470 | } |
| 471 | |
| 472 | reset_timeout(); |
| 473 | |
| 474 | return; |
| 475 | } |
| 476 | |
| 477 | } |