src/iop.c

   1 /**************************************************************************/
   2 /* ---------------------------------------------------------------------- */
   3 /* Copyright (C) 2006 - 2008 FRESCOR consortium partners:                 */
   4 /*                                                                        */
   5 /*   Universidad de Cantabria,              SPAIN                         */
   6 /*   University of York,                    UK                            */
   7 /*   Scuola Superiore Sant'Anna,            ITALY                         */
   8 /*   Kaiserslautern University,             GERMANY                       */
   9 /*   Univ. Politécnica  Valencia,           SPAIN                        */
  10 /*   Czech Technical University in Prague,  CZECH REPUBLIC                */
  11 /*   ENEA                                   SWEDEN                        */
  12 /*   Thales Communication S.A.              FRANCE                        */
  13 /*   Visual Tools S.A.                      SPAIN                         */
  14 /*   Rapita Systems Ltd                     UK                            */
  15 /*   Evidence                               ITALY                         */
  16 /*                                                                        */
  17 /*   See http://www.frescor.org for a link to partners' websites          */
  18 /*                                                                        */
  19 /*          FRESCOR project (FP6/2005/IST/5-034026) is funded             */
  20 /*       in part by the European Union Sixth Framework Programme          */
  21 /*       The European Union is not liable of any use that may be          */
  22 /*       made of this code.                                               */
  23 /*                                                                        */
  24 /*                                                                        */
  25 /*  This file is part of FORB (Frescor Object Request Broker)             */
  26 /*                                                                        */
  27 /* FORB is free software; you can redistribute it and/or modify it        */
  28 /* under terms of the GNU General Public License as published by the      */
  29 /* Free Software Foundation; either version 2, or (at your option) any    */
  30 /* later version.  FORB is distributed in the hope that it will be        */
  31 /* useful, but WITHOUT ANY WARRANTY; without even the implied warranty    */
  32 /* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU    */
  33 /* General Public License for more details. You should have received a    */
  34 /* copy of the GNU General Public License along with FORB; see file       */
  35 /* COPYING. If not, write to the Free Software Foundation, 675 Mass Ave,  */
  36 /* Cambridge, MA 02139, USA.                                              */
  37 /*                                                                        */
  38 /* As a special exception, including FORB header files in a file,         */
  39 /* instantiating FORB generics or templates, or linking other files       */
  40 /* with FORB objects to produce an executable application, does not       */
  41 /* by itself cause the resulting executable application to be covered     */
  42 /* by the GNU General Public License. This exception does not             */
  43 /* however invalidate any other reasons why the executable file might be  */
  44 /* covered by the GNU Public License.                                     */
  45 /**************************************************************************/
  46
  47 /**
  48  * @file   iop.c
  49  * @author Michal Sojka <sojkam1@fel.cvut.cz>
  50  * @date   Mon Sep  1 21:51:58 2008
  51  *
  52  * @brief  Implementation of Inter-ORB protocol.
  53  *
  54  *
  55  */
  56 #include "iop.h"
  57 #include <forb/cdr.h>
  58 #include <forb/object.h>
  59 #include "proto.h"
  60 #include <ul_log.h>
  61 #include "exec_req.h"
  62 #include <errno.h>
  63 #include "peer.h"
  64
  65 /** Version of the protocol */
  66 #define VER_MAJOR 0
  67 #define VER_MINOR 0
  68
  69 #define VER(major, minor) ((major)<<8 || (minor))
  70
  71 extern UL_LOG_CUST(ulogd_forb_iop);
  72
  73
  74 CORBA_boolean
  75 forb_iop_prepend_message_header(CDR_Codec *codec, forb_iop_message_type mt)
  76 {
  77         CORBA_boolean ret;
  78         forb_iop_message_header mh;
  79         mh.proto_version.major = VER_MAJOR;
  80         mh.proto_version.minor = VER_MINOR;
  81         mh.message_type = mt;
  82         mh.flags = (codec->data_endian == LittleEndian) ? forb_iop_LITTLE_ENDIAN : 0;
  83         mh.message_size = CDR_data_size(codec);
  84         ret = CDR_buffer_prepend(codec, forb_iop_MESSAGE_HEADER_SIZE);
  85         if (ret) {
  86                 ret = forb_iop_message_header_serialize(codec, &mh);
  87         }
  88         return ret;
  89 }
  90
  91 CORBA_boolean
  92 forb_iop_prepare_request(forb_request_t *req,
  93                          char *iface,
  94                          unsigned method_ind,
  95                          CORBA_Environment *env)
  96 {
  97         CORBA_boolean ret;
  98         forb_iop_request_header rh;
  99
 100         rh.request_id = req->request_id;
 101         rh.iface = iface;
 102         rh.objkey = forb_object_to_key(req->obj);
 103         rh.method_index = method_ind;
 104         rh.source = forb_object_to_forb(req->obj)->server_id;
 105         ret = forb_iop_request_header_serialize(&req->cdr_request, &rh);
 106         if (ret) {
 107                 /* Request body is 8 byte aligned */
 108                 ret = CDR_put_align(&req->cdr_request, 8);
 109         }
 110         return ret;
 111 }
 112
 113 CORBA_boolean
 114 forb_iop_prepare_hello(CDR_Codec *codec,
 115                        const forb_server_id *server_id,
 116                        const void *src_addr,
 117                        CORBA_boolean (*serialize_addr)(CDR_Codec *codec, const void *addr))
 118 {
 119         if (!forb_server_id_serialize(codec, server_id)) return CORBA_FALSE;
 120         if (serialize_addr) {
 121                 if (!serialize_addr(codec, src_addr)) return CORBA_FALSE;
 122         }
 123         if (!forb_iop_prepend_message_header(codec, forb_iop_HELLO)) return CORBA_FALSE;
 124         return CORBA_TRUE;
 125 }
 126
 127 bool
 128 forb_iop_process_message_header(forb_iop_message_header *mh, CDR_Codec *codec)
 129 {
 130         /* FIXME: If we have multiple protocol versions, use different
 131          * type (independent from version) for return value instead of
 132          * mh */
 133         forb_iop_version_deserialize(codec, &mh->proto_version);
 134         switch (VER(mh->proto_version.major, mh->proto_version.minor)) {
 135                 case VER(VER_MAJOR, VER_MINOR):
 136                         forb_iop_message_type_deserialize(codec, &mh->message_type);
 137                         forb_iop_message_flags_deserialize(codec, &mh->flags);
 138                         /* Check whwther the type is meaningfull */
 139                         switch (mh->message_type) {
 140                                 case forb_iop_REQUEST:
 141                                 case forb_iop_REPLY:
 142                                 case forb_iop_HELLO:
 143                                         break;
 144                                 default:
 145                                         return false;
 146                         }
 147                         codec->data_endian = (mh->flags && forb_iop_LITTLE_ENDIAN) ?
 148                                 LittleEndian : BigEndian;
 149                         CORBA_unsigned_long_deserialize(codec, &mh->message_size);
 150                         return true;
 151                         break;
 152                 default:
 153                         return false;
 154         }
 155 }
 156
 157 static inline CORBA_boolean
 158 forb_exception_serialize(CDR_Codec *codec, struct forb_env *env)
 159 {
 160         return CORBA_long_serialize(codec, &env->major);
 161 }
 162
 163 static inline CORBA_boolean
 164 forb_exception_deserialize(CDR_Codec *codec, struct forb_env *env)
 165 {
 166         /* TODO: Declare exceptions in IDL and don't typecast here. */
 167         return CORBA_long_deserialize(codec, (CORBA_long*)&env->major);
 168 }
 169
 170 void
 171 forb_iop_send_reply(forb_t *forb,
 172            forb_server_id *dest,
 173            CDR_Codec *codec,
 174            CORBA_long request_id,
 175            struct forb_env *env)
 176 {
 177         forb_iop_reply_header reply_header;
 178         CORBA_boolean ret;
 179         forb_peer_t *peer;
 180         fosa_abs_time_t timeout;
 181
 182         reply_header.request_id = request_id;
 183         reply_header.flags = 0;
 184         if (forb_exception_occurred(env)) {
 185                 reply_header.flags |= forb_iop_FLAG_EXCEPTION;
 186                 CDR_buffer_reset(codec, forb_iop_MESSAGE_HEADER_SIZE +
 187                                         forb_iop_REPLY_HEADER_SIZE);
 188                 forb_exception_serialize(codec, env);
 189         }
 190         /* forb_iop_REPLY_HEADER_SIZE equals to 8 even if the real
 191          * header is shorter. We want reply data to be 8 byte
 192          * aligned */
 193         ret = CDR_buffer_prepend(codec, forb_iop_REPLY_HEADER_SIZE);
 194         if (!ret) {
 195                 goto err;
 196         }
 197         ret = forb_iop_reply_header_serialize(codec, &reply_header);
 198         if (!ret) {
 199                 goto err;
 200         }
 201         forb_iop_prepend_message_header(codec, forb_iop_REPLY);
 202
 203         fosa_clock_get_time(FOSA_CLOCK_ABSOLUTE, &timeout);
 204         timeout = fosa_abs_time_incr(timeout,
 205                                      fosa_msec_to_rel_time(1000));
 206
 207         peer = forb_get_next_hop(forb, dest, &timeout);
 208         if (!peer) {
 209                 ul_logerr("Reply destination not found\n");
 210                 goto err;
 211         }
 212         forb_proto_send(peer, codec);
 213         forb_peer_put(peer);
 214 err:
 215         ;
 216 }
 217
 218
 219 static void
 220 process_request(forb_port_t *port, CDR_Codec *codec, uint32_t message_size)
 221 {
 222         forb_iop_request_header request_header;
 223         CORBA_boolean ret;
 224         forb_object obj;
 225         size_t n;
 226         forb_t *forb = port->forb;
 227         struct forb_env env;
 228         CDR_Codec reply_codec;
 229         forb_exec_req_t *exec_req;
 230         uint32_t req_size, data_size, header_size;
 231         char str[32];
 232
 233         data_size = CDR_data_size(codec);
 234         ret = forb_iop_request_header_deserialize(codec, &request_header);
 235         if (!ret) {
 236                 ul_logerr("Malformed request recevied\n");
 237                 env.major = FORB_EX_COMM_FAILURE;
 238                 goto out;
 239         }
 240         ret = CDR_get_align(codec, 8);
 241         if (!ret) {
 242                 ul_logerr("Malformed request recevied\n");
 243                 env.major = FORB_EX_COMM_FAILURE;
 244                 goto out;
 245         }
 246
 247         header_size = data_size - CDR_data_size(codec);
 248         req_size = message_size - header_size;
 249
 250         ul_logdeb("rcvd request: src=%s, id=%u, iface=%s, method=%hd\n",
 251                   forb_server_id_to_string(str, &request_header.source, sizeof(str)),
 252                   request_header.request_id,
 253                   request_header.iface,
 254                   request_header.method_index);
 255
 256         obj = forb_key_to_object(forb, request_header.objkey);
 257         if (!obj) {
 258                 ul_logerr("Nonexistent object key\n");
 259                 env.major = FORB_EX_OBJECT_NOT_EXIST;
 260                 goto send_execption;
 261         }
 262
 263         n = strlen(request_header.iface);
 264         if (strncmp(request_header.iface, obj->interface->name, n) != 0) {
 265                 env.major = FORB_EX_INV_OBJREF;
 266                 ul_logerr("Object reference has incorrect type\n");
 267                 goto send_execption;
 268         }
 269         if (request_header.method_index >= obj->interface->num_methods) {
 270                 env.major = FORB_EX_INV_IDENT;
 271                 ul_logerr("To high method number\n");
 272                 goto send_execption;
 273         }
 274
 275         if (!obj->executor) {
 276                 env.major = FORB_EX_NO_IMPLEMENT;
 277                 ul_logerr("No executor for object\n");
 278                 goto send_execption;
 279
 280         }
 281
 282         /* Enqueue execution request */
 283         exec_req = forb_malloc(sizeof(*exec_req));
 284         if (exec_req) {
 285                 exec_req->request_id = request_header.request_id;
 286                 exec_req->source = request_header.source;
 287                 exec_req->obj = obj;
 288                 exec_req->method_index = request_header.method_index;
 289                 /* Copy the request to exec_req */
 290                 CDR_codec_init_static(&exec_req->codec, codec->orb);
 291                 ret = CDR_buffer_init(&exec_req->codec,
 292                                       req_size,
 293                                       0);
 294                 if (!ret) {
 295                         env.major = FORB_EX_NO_MEMORY;
 296                         ul_logerr("No memory for executor request bufer of size %d (header_size=%d)\n",
 297                                   req_size, header_size);
 298                         goto send_execption;
 299                 }
 300                 exec_req->codec.data_endian = codec->data_endian;
 301                 CDR_buffer_gets(codec, exec_req->codec.buffer, req_size);
 302                 /* TODO: Use better data structure for incomming
 303                    buffer to achieve zero-copy behaviour. */
 304                 forb_exec_req_ins_tail(obj->executor, exec_req);
 305         } else {
 306                 env.major = FORB_EX_NO_MEMORY;
 307                 ul_logerr("No memory for executor request\n");
 308                 goto send_execption;
 309         }
 310
 311 out:
 312         return;
 313
 314 send_execption:
 315         CDR_codec_init_static(&reply_codec, codec->orb);
 316         ret = CDR_buffer_init(&reply_codec, 4096,
 317                               forb_iop_MESSAGE_HEADER_SIZE +
 318                               forb_iop_REPLY_HEADER_SIZE);
 319         if (!ret) {
 320                 ul_logerr("No memory for exception reply buffer\n");
 321                 return;
 322         }
 323
 324         forb_iop_send_reply(port->forb, &request_header.source,
 325                             &reply_codec, request_header.request_id, &env);
 326         CDR_codec_release_buffer(&reply_codec);
 327 }
 328
 329 static void
 330 process_reply(forb_port_t *port, CDR_Codec *codec)
 331 {
 332         forb_iop_reply_header rh;
 333         forb_t *forb = port->forb;
 334         forb_request_t *req;
 335
 336         forb_iop_reply_header_deserialize(codec, &rh);
 337         /* Reply data are 8 byte aligned */
 338         CDR_get_align(codec, 8);
 339         ul_logdeb("rcvd reply: id=%u\n", rh.request_id);
 340         req = forb_request_find(forb, &rh.request_id);
 341         if (!req) {
 342                 ul_logerr("Received reply to unknown request_id %u\n", rh.request_id);
 343                 return;
 344         }
 345         forb_request_delete(forb, req); /* Deregister request from forb */
 346
 347         if (rh.flags & forb_iop_FLAG_EXCEPTION) {
 348                 forb_exception_deserialize(codec, req->env);
 349         } else {
 350                 req->cdr_reply = codec;
 351         }
 352
 353         /* Tell the stub where to signal that reply processing is
 354          * finished */
 355         req->reply_processed = &port->reply_processed;
 356
 357         /* Resume the stub waiting in forb_wait_for_reply() */
 358         forb_syncobj_signal(&req->reply_ready);
 359
 360         /* Wait for stub to process the results from the codec's buffer */
 361         forb_syncobj_wait(&port->reply_processed);
 362 }
 363
 364 /**
 365  * Process incomming HELLO messages.
 366  *
 367  * For every incomming HELLO message the peer table is searched
 368  * whether it already contains a record for that peer or not. If not,
 369  * the new peer is added to the table and another hello message is
 370  * sent so that the new peer discovers us quickly.
 371  *
 372  * @param port Port, where hello was received
 373  * @param codec Buffer with the hello message
 374  */
 375 static void
 376 process_hello(forb_port_t *port, CDR_Codec *codec)
 377 {
 378         forb_server_id server_id;
 379         void *addr = NULL;
 380         forb_peer_t *peer;
 381         forb_t *forb = port->forb;
 382
 383 /*      printf("Hello received at port %p\n", port); */
 384
 385         forb_server_id_deserialize(codec, &server_id);
 386         {
 387                 char str[60];
 388                 ul_logdeb("rcvd hello from %s\n", forb_server_id_to_string(str, &server_id, sizeof(str)));
 389         }
 390         if (port->proto->deserialize_addr) {
 391                 port->proto->deserialize_addr(codec, &addr);
 392         }
 393         if (forb_server_id_cmp(&server_id, &forb->server_id) != 0) {
 394                 peer = forb_peer_find(forb, &server_id);
 395                 if (peer && peer->state == FORB_PEER_DISCOVERED) {
 396                         /* TODO: Update last hello receive time */
 397                         forb_peer_put(peer);
 398                 } else {
 399                         /* New peer discovered */
 400                         bool notify_waiters = false;
 401                         if (peer /* && peer->state == FORB_PEER_WANTED */) {
 402                                 notify_waiters = true;
 403                         } else {
 404                                 peer = forb_peer_new();
 405                         }
 406                         if (peer) {
 407                                 fosa_mutex_lock(&forb->peer_mutex);
 408                                 peer->server_id = server_id;
 409                                 peer->port = port;
 410                                 peer->addr = addr;
 411                                 peer->state = FORB_PEER_DISCOVERED;
 412                                 if (notify_waiters) {
 413                                         fosa_cond_broadcast(&peer->cond);
 414                                 } else {
 415                                         forb_peer_get(peer);
 416                                         forb_peer_nolock_insert(forb, peer);
 417                                 }
 418                                 forb_peer_get(peer);
 419                                 forb_port_peer_ins_tail(port, peer);
 420                                 fosa_mutex_unlock(&forb->peer_mutex);
 421                                 forb_peer_put(peer);
 422                         }
 423                         /* Broadcast our hello packet now */
 424                         forb_syncobj_signal(&port->hello);
 425                 }
 426         }
 427 }
 428
 429 static void
 430 process_message(forb_port_t *port, const forb_iop_message_header *mh,
 431                 CDR_Codec *codec)
 432 {
 433         CORBA_long data_size = CDR_data_size(codec);
 434         /* TODO: Check destination address, whether the message is for
 435          * us or should be routed. */
 436
 437         /* TODO: If there is some processing error, skip the rest of
 438          * the message according mh.message_size. */
 439         switch (mh->message_type) {
 440                 case forb_iop_REQUEST:
 441                         process_request(port, codec, mh->message_size);
 442                         break;
 443                 case forb_iop_REPLY:
 444                         process_reply(port, codec);
 445                         break;
 446                 case forb_iop_HELLO:
 447                         process_hello(port, codec);
 448                         break;
 449                 default:
 450                         ul_logmsg("rcvd unknown message type\n");
 451                         break;
 452         }
 453         if (CDR_data_size(codec) != data_size - mh->message_size) {
 454                 size_t processed = data_size - CDR_data_size(codec);
 455                 ul_logmsg("Message of type %d handled incorrectly (size=%d, processed=%d); fixing\n",
 456                           mh->message_type, mh->message_size, processed);
 457                           ;
 458                 codec->rptr += mh->message_size - processed;
 459         }
 460 }
 461
 462 /**
 463  * Thread run for every port to receive FORB messages from that port.
 464  *
 465  * @param arg Pointer to ::forb_port_t typecasted to void *.
 466  *
 467  * @return Always NULL
 468  */
 469 void *forb_iop_receiver_thread(void *arg)
 470 {
 471         forb_port_t *port = arg;
 472         const forb_proto_t *proto = port->proto;
 473         CDR_Codec *c = &port->codec;
 474         size_t rcvd, len;
 475         forb_iop_message_header mh;
 476         bool header_received = false;
 477
 478         while (!port->finish) {
 479                 if (c->rptr == c->wptr) {
 480                         /* The buffer is empty now - start writing from begining*/
 481                         CDR_buffer_reset(c, 0);
 482                 }
 483                 /* TODO: If there is not enough space for reception,
 484                  * we should shift the already received data to the
 485                  * beginning of the buffer. */
 486                 rcvd = proto->recv(port,
 487                                    &c->buffer[c->wptr],
 488                                    c->wptr_max - c->wptr);
 489                 c->wptr += rcvd;
 490                 c->wptr_last = c->wptr;
 491
 492                 /* While there are some data in the buffer, process them. */
 493                 while (CDR_data_size(c) > 0) {
 494                         len = CDR_data_size(c);
 495                         /* Wait for and then process message header */
 496                         if (!header_received) {
 497                                 if (len >= forb_iop_MESSAGE_HEADER_SIZE) {
 498                                         if (c->rptr % 8 != 0) {
 499                                                 ul_logerr("Header doesn't start at 8 byte bounday\n");
 500                                         }
 501                                         header_received = forb_iop_process_message_header(&mh, c);
 502                                         len = CDR_data_size(c);
 503                                 } else {
 504                                         break; /* Wait for more data to arrive*/
 505                                 }
 506                         }
 507
 508                         /* Wait for and then process the message body */
 509                         if (header_received) {
 510                                 if (len >= mh.message_size) {
 511                                         process_message(port, &mh, c);
 512                                         /* Wait for the next message */
 513                                         header_received = false;
 514                                 } else {
 515                                         break; /* Wait for more data to arrive*/
 516                                 }
 517                         }
 518                 }
 519         }
 520         return NULL;
 521 }
 522
 523 static void
 524 discovery_cleanup(void *codec)
 525 {
 526         CDR_codec_release_buffer((CDR_Codec*)codec);
 527         /* TODO: Broadcast some kind of bye bye message */
 528 }
 529
 530
 531 /**
 532  * Thread run for every port to broadcast HELLO messages. These
 533  * messages are used for a FORB to discover all peers (and in future
 534  * also to detect their disconnection).
 535  *
 536  * @param arg Pointer to ::forb_port_t typecasted to void *.
 537  *
 538  * @return Always NULL
 539  */
 540 void *forb_iop_discovery_thread(void *arg)
 541 {
 542         forb_port_t *port = arg;
 543         const forb_proto_t *proto = port->proto;
 544         CDR_Codec codec;
 545         fosa_abs_time_t hello_time;
 546         fosa_rel_time_t hello_interval = fosa_msec_to_rel_time(1000*proto->hello_interval);
 547         int ret;
 548
 549         CDR_codec_init_static(&codec, port->forb->orb);
 550         CDR_buffer_init(&codec, 1024, 0);
 551
 552         pthread_cleanup_push(discovery_cleanup, &codec);
 553
 554         /* Next hello interval is now */
 555         fosa_clock_get_time(FOSA_CLOCK_ABSOLUTE, &hello_time);
 556
 557         while (!port->finish) {
 558                 /* Wait for next hello interval or until somebody
 559                  * signals us. */
 560                 ret = forb_syncobj_timedwait(&port->hello, &hello_time);
 561                 /* sem_timedwait would be more appropriate */
 562                 if (ret == FOSA_ETIMEDOUT) {
 563                         hello_time = fosa_abs_time_incr(hello_time, hello_interval);
 564                 } else if (ret != 0) {
 565                         ul_logerr("hello syncobj error: %s\n", strerror(ret));
 566                 }
 567
 568                 if (port->finish) break;
 569
 570                 CDR_buffer_reset(&codec, forb_iop_MESSAGE_HEADER_SIZE);
 571                 forb_iop_prepare_hello(&codec, &port->forb->server_id, port->addr,
 572                                        proto->serialize_addr);
 573 /*              printf("Broadcasting hello from port %p\n", port);  */
 574                 proto->broadcast(port, &codec.buffer[codec.rptr],
 575                                  CDR_data_size(&codec));
 576         }
 577
 578         pthread_cleanup_pop(1);
 579         return NULL;
 580 }
 581
 582