Robust/src/Runtime/DSTM/interface/dstmserver.c

   1 /* Coordinator => Machine that initiates the transaction request call for commiting a transaction
   2  * Participant => Machines that host the objects involved in a transaction commit */
   3
   4 #include <stdio.h>
   5 #include <stdlib.h>
   6 #include <string.h>
   7 #include <pthread.h>
   8 #include <netdb.h>
   9 #include <fcntl.h>
  10 #include <errno.h>
  11 #include <string.h>
  12 #include "dstm.h"
  13 #include "mlookup.h"
  14 #include "llookup.h"
  15 #include "threadnotify.h"
  16 #ifdef COMPILER
  17 #include "thread.h"
  18 #endif
  19
  20
  21 #define LISTEN_PORT 2156
  22 #define BACKLOG 10 //max pending connections
  23 #define RECEIVE_BUFFER_SIZE 2048
  24
  25 extern int classsize[];
  26
  27 objstr_t *mainobjstore;
  28 pthread_mutex_t mainobjstore_mutex;
  29 pthread_mutexattr_t mainobjstore_mutex_attr; /* Attribute for lock to make it a recursive lock */
  30
  31 /* This function initializes the main objects store and creates the
  32  * global machine and location lookup table */
  33
  34 int dstmInit(void)
  35 {
  36         mainobjstore = objstrCreate(DEFAULT_OBJ_STORE_SIZE);
  37         /* Initialize attribute for mutex */
  38         pthread_mutexattr_init(&mainobjstore_mutex_attr);
  39         pthread_mutexattr_settype(&mainobjstore_mutex_attr, PTHREAD_MUTEX_RECURSIVE_NP);
  40         pthread_mutex_init(&mainobjstore_mutex, &mainobjstore_mutex_attr);
  41         if (mhashCreate(HASH_SIZE, LOADFACTOR))
  42                 return 1; //failure
  43
  44         if (lhashCreate(HASH_SIZE, LOADFACTOR))
  45                 return 1; //failure
  46
  47         if (notifyhashCreate(N_HASH_SIZE, N_LOADFACTOR))
  48                 return 1; //failure
  49
  50         return 0;
  51 }
  52
  53 /* This function starts the thread to listen on a socket
  54  * for tranaction calls */
  55 void *dstmListen()
  56 {
  57         int listenfd, acceptfd;
  58         struct sockaddr_in my_addr;
  59         struct sockaddr_in client_addr;
  60         socklen_t addrlength = sizeof(struct sockaddr);
  61         pthread_t thread_dstm_accept;
  62         int i;
  63         int setsockflag=1;
  64
  65         listenfd = socket(AF_INET, SOCK_STREAM, 0);
  66         if (listenfd == -1)
  67         {
  68                 perror("socket");
  69                 exit(1);
  70         }
  71
  72         if (setsockopt(listenfd, SOL_SOCKET, SO_REUSEADDR, &setsockflag, sizeof (setsockflag)) < 0) {
  73           perror("socket");
  74           exit(1);
  75         }
  76 #ifdef MAC
  77         if (setsockopt(listenfd, SOL_SOCKET, SO_NOSIGPIPE, &setsockflag, sizeof (setsockflag)) < 0) {
  78           perror("socket");
  79           exit(1);
  80         }
  81 #endif
  82
  83         my_addr.sin_family = AF_INET;
  84         my_addr.sin_port = htons(LISTEN_PORT);
  85         my_addr.sin_addr.s_addr = INADDR_ANY;
  86         memset(&(my_addr.sin_zero), '\0', 8);
  87
  88         if (bind(listenfd, (struct sockaddr *)&my_addr, addrlength) == -1)
  89         {
  90                 perror("bind");
  91                 exit(1);
  92         }
  93
  94         if (listen(listenfd, BACKLOG) == -1)
  95         {
  96                 perror("listen");
  97                 exit(1);
  98         }
  99
 100         printf("Listening on port %d, fd = %d\n", LISTEN_PORT, listenfd);
 101         while(1)
 102         {
 103           int retval;
 104           acceptfd = accept(listenfd, (struct sockaddr *)&client_addr, &addrlength);
 105           do {
 106             retval=pthread_create(&thread_dstm_accept, NULL, dstmAccept, (void *)acceptfd);
 107           } while(retval!=0);
 108           pthread_detach(thread_dstm_accept);
 109         }
 110 }
 111 /* This function accepts a new connection request, decodes the control message in the connection
 112  * and accordingly calls other functions to process new requests */
 113 void *dstmAccept(void *acceptfd)
 114 {
 115         int val, retval, size, sum;
 116         unsigned int oid;
 117         char *buffer;
 118         char control,ctrl;
 119         char *ptr;
 120         void *srcObj;
 121         objheader_t *h;
 122         trans_commit_data_t transinfo;
 123         unsigned short objType, *versionarry, version;
 124         unsigned int *oidarry, numoid, mid, threadid;
 125
 126         transinfo.objlocked = NULL;
 127         transinfo.objnotfound = NULL;
 128         transinfo.modptr = NULL;
 129         transinfo.numlocked = 0;
 130         transinfo.numnotfound = 0;
 131
 132         /* Receive control messages from other machines */
 133         if((retval = recv((int)acceptfd, &control, sizeof(char), 0)) <= 0) {
 134                 printf("%s() Error: Receiving control = %d at %s, %d\n", __func__, control, __FILE__, __LINE__);
 135                 pthread_exit(NULL);
 136         }
 137
 138         switch(control) {
 139                 case READ_REQUEST:
 140                         /* Read oid requested and search if available */
 141                         if((retval = recv((int)acceptfd, &oid, sizeof(unsigned int), 0)) <= 0) {
 142                                 perror("Error: receiving 0x0 object from cooridnator\n");
 143                                 pthread_exit(NULL);
 144                         }
 145                         if((srcObj = mhashSearch(oid)) == NULL) {
 146                                 printf("Error: Object 0x%x is not found in Main Object Store %s, %d\n", oid, __FILE__, __LINE__);
 147                                 pthread_exit(NULL);
 148                         }
 149                         h = (objheader_t *) srcObj;
 150                         GETSIZE(size, h);
 151                         size += sizeof(objheader_t);
 152
 153                         if (h == NULL) {
 154                                 ctrl = OBJECT_NOT_FOUND;
 155                                 if(send((int)acceptfd, &ctrl, sizeof(char), MSG_NOSIGNAL) < sizeof(char)) {
 156                                         perror("Error sending control msg to coordinator\n");
 157                                         pthread_exit(NULL);
 158                                 }
 159                         } else {
 160                                 /* Type */
 161                                 char msg[]={OBJECT_FOUND, 0, 0, 0, 0};
 162                                 *((int *)&msg[1])=size;
 163                                 if(send((int)acceptfd, &msg, sizeof(msg), MSG_NOSIGNAL) < sizeof(msg)) {
 164                                         perror("Error sending size of object to coordinator\n");
 165                                         pthread_exit(NULL);
 166                                 }
 167                                 if(send((int)acceptfd, h, size, MSG_NOSIGNAL) < size) {
 168                                         perror("Error in sending object\n");
 169                                         pthread_exit(NULL);
 170                                 }
 171                         }
 172                         break;
 173
 174                 case READ_MULT_REQUEST:
 175                         break;
 176
 177                 case MOVE_REQUEST:
 178                         break;
 179
 180                 case MOVE_MULT_REQUEST:
 181                         break;
 182
 183                 case TRANS_REQUEST:
 184                         /* Read transaction request */
 185                         if((val = readClientReq(&transinfo, (int)acceptfd)) != 0) {
 186                                 printf("Error: In readClientReq() %s, %d\n", __FILE__, __LINE__);
 187                                 pthread_exit(NULL);
 188                         }
 189                         break;
 190                 case TRANS_PREFETCH:
 191                         do {
 192                                 if((val = prefetchReq((int)acceptfd)) != 0) {
 193                                         printf("Error: In prefetchReq() %s, %d\n", __FILE__, __LINE__);
 194                                         pthread_exit(NULL);
 195                                 }
 196
 197                                 if((retval = recv((int)acceptfd, &control, sizeof(char), 0)) < 0) {
 198                                         printf("%s() Error: Receiving control = %d at %s, %d\n", __func__, control, __FILE__, __LINE__);
 199                                         pthread_exit(NULL);
 200                                 } else if(retval == 0) {
 201                                         printf("%s() Error: socket closed at the requesting side\n");
 202                                         pthread_exit(NULL);
 203                                 }
 204
 205                         } while (control == TRANS_PREFETCH);
 206
 207                         break;
 208                 case TRANS_PREFETCH_RESPONSE:
 209                         if((val = getPrefetchResponse((int) acceptfd)) != 0) {
 210                                 printf("Error: In getPrefetchResponse() %s, %d\n", __FILE__, __LINE__);
 211                                 pthread_exit(NULL);
 212                         }
 213                         break;
 214                 case START_REMOTE_THREAD:
 215                         retval = recv((int)acceptfd, &oid, sizeof(unsigned int), 0);
 216                         if (retval <= 0)
 217                                 perror("dstmAccept(): error receiving START_REMOTE_THREAD msg");
 218                         else if (retval != sizeof(unsigned int))
 219                                 printf("dstmAccept(): incorrect msg size %d for START_REMOTE_THREAD %s, %d\n",
 220                                         retval, __FILE__, __LINE__);
 221                         else
 222                         {
 223                                 objType = getObjType(oid);
 224                                 startDSMthread(oid, objType);
 225                         }
 226                         break;
 227
 228                 case THREAD_NOTIFY_REQUEST:
 229                         retval = recv((int)acceptfd, &numoid, sizeof(unsigned int), 0);
 230                         size = (sizeof(unsigned int) + sizeof(unsigned short)) * numoid + 2 * sizeof(unsigned int);
 231                         if((buffer = calloc(1,size)) == NULL) {
 232                                 printf("%s() Calloc error at %s, %d\n", __func__, __FILE__, __LINE__);
 233                                 pthread_exit(NULL);
 234                         }
 235                         sum = 0;
 236                         do {
 237                                 sum += recv((int)acceptfd, buffer+sum, size-sum, 0);
 238                         } while(sum < size);
 239
 240                         oidarry = calloc(numoid, sizeof(unsigned int));
 241                         memcpy(oidarry, buffer, sizeof(unsigned int) * numoid);
 242                         size = sizeof(unsigned int) * numoid;
 243                         versionarry = calloc(numoid, sizeof(unsigned short));
 244                         memcpy(versionarry, buffer+size, sizeof(unsigned short) * numoid);
 245                         size += sizeof(unsigned short) * numoid;
 246                         mid = *((unsigned int *)(buffer+size));
 247                         size += sizeof(unsigned int);
 248                         threadid = *((unsigned int *)(buffer+size));
 249                         processReqNotify(numoid, oidarry, versionarry, mid, threadid);
 250                         free(buffer);
 251
 252                         break;
 253
 254                 case THREAD_NOTIFY_RESPONSE:
 255                         size = sizeof(unsigned short) + 2 * sizeof(unsigned int);
 256                         if((buffer = calloc(1,size)) == NULL) {
 257                                 printf("%s() Calloc error at %s, %d\n", __func__, __FILE__, __LINE__);
 258                                 pthread_exit(NULL);
 259                         }
 260
 261                         sum = 0;
 262                         do {
 263                                 sum += recv((int)acceptfd, buffer+sum, size-sum, 0);
 264                         } while(sum < size);
 265
 266                         oid = *((unsigned int *)buffer);
 267                         size = sizeof(unsigned int);
 268                         version = *((unsigned short *)(buffer+size));
 269                         size += sizeof(unsigned short);
 270                         threadid = *((unsigned int *)(buffer+size));
 271                         threadNotify(oid,version,threadid);
 272                         free(buffer);
 273
 274                         break;
 275                 default:
 276                         printf("Error: dstmAccept() Unknown opcode %d at %s, %d\n", control, __FILE__, __LINE__);
 277         }
 278
 279         /* Close connection */
 280         if (close((int)acceptfd) == -1)
 281                 perror("close");
 282         pthread_exit(NULL);
 283 }
 284
 285 /* This function reads the information available in a transaction request
 286  * and makes a function call to process the request */
 287 int readClientReq(trans_commit_data_t *transinfo, int acceptfd) {
 288         char *ptr;
 289         void *modptr;
 290         unsigned int *oidmod, oid;
 291         fixed_data_t fixed;
 292         objheader_t *headaddr;
 293         int sum = 0, i, N, n, val;
 294
 295         oidmod = NULL;
 296
 297         /* Read fixed_data_t data structure */
 298         N = sizeof(fixed) - 1;
 299         ptr = (char *)&fixed;;
 300         fixed.control = TRANS_REQUEST;
 301         do {
 302                 n = recv((int)acceptfd, (void *) ptr+1+sum, N-sum, 0);
 303                 sum += n;
 304         } while(sum < N && n != 0);
 305
 306         /* Read list of mids */
 307         int mcount = fixed.mcount;
 308         N = mcount * sizeof(unsigned int);
 309         unsigned int listmid[mcount];
 310         ptr = (char *) listmid;
 311         sum = 0;
 312         do {
 313                 n = recv((int)acceptfd, (void *) ptr+sum, N-sum, 0);
 314                 sum += n;
 315         } while(sum < N && n != 0);
 316
 317         /* Read oid and version tuples for those objects that are not modified in the transaction */
 318         int numread = fixed.numread;
 319         N = numread * (sizeof(unsigned int) + sizeof(unsigned short));
 320         char objread[N];
 321         if(numread != 0) { //If pile contains more than one object to be read,
 322                           // keep reading all objects
 323                 sum = 0;
 324                 do {
 325                         n = recv((int)acceptfd, (void *) objread+sum, N-sum, 0);
 326                         sum += n;
 327                 } while(sum < N && n != 0);
 328         }
 329
 330         /* Read modified objects */
 331         if(fixed.nummod != 0) {
 332                 if ((modptr = calloc(1, fixed.sum_bytes)) == NULL) {
 333                         printf("calloc error for modified objects %s, %d\n", __FILE__, __LINE__);
 334                         return 1;
 335                 }
 336                 sum = 0;
 337                 do { // Recv the objs that are modified by the Coordinator
 338                         n = recv((int)acceptfd, (char *) modptr+sum, fixed.sum_bytes-sum, 0);
 339                         sum += n;
 340                 } while (sum < fixed.sum_bytes && n != 0);
 341         }
 342
 343         /* Create an array of oids for modified objects */
 344         oidmod = (unsigned int *) calloc(fixed.nummod, sizeof(unsigned int));
 345         if (oidmod == NULL)
 346         {
 347                 printf("calloc error %s, %d\n", __FILE__, __LINE__);
 348                 return 1;
 349         }
 350         ptr = (char *) modptr;
 351         for(i = 0 ; i < fixed.nummod; i++) {
 352           int tmpsize;
 353           headaddr = (objheader_t *) ptr;
 354           oid = OID(headaddr);
 355           oidmod[i] = oid;
 356           GETSIZE(tmpsize, headaddr);
 357           ptr += sizeof(objheader_t) + tmpsize;
 358         }
 359
 360         /*Process the information read */
 361         if((val = processClientReq(&fixed, transinfo, listmid, objread, modptr, oidmod, acceptfd)) != 0) {
 362                 printf("Error: In processClientReq() %s, %d\n", __FILE__, __LINE__);
 363                 /* Free resources */
 364                 if(oidmod != NULL) {
 365                         free(oidmod);
 366                 }
 367                 return 1;
 368         }
 369
 370         /* Free resources */
 371         if(oidmod != NULL) {
 372                 free(oidmod);
 373         }
 374
 375         return 0;
 376 }
 377
 378 /* This function processes the Coordinator's transaction request using "handleTransReq"
 379  * function and sends a reply to the co-ordinator.
 380  * Following this it also receives a new control message from the co-ordinator and processes this message*/
 381 int processClientReq(fixed_data_t *fixed, trans_commit_data_t *transinfo,
 382                 unsigned int *listmid, char *objread, void *modptr, unsigned int *oidmod, int acceptfd) {
 383         char control, sendctrl, retval;
 384         objheader_t *tmp_header;
 385         void *header;
 386         int  i = 0, val;
 387
 388         /* Send reply to the Coordinator */
 389         if((retval = handleTransReq(fixed, transinfo, listmid, objread, modptr,acceptfd)) == 0 ) {
 390                 printf("Error: In handleTransReq() %s, %d\n", __FILE__, __LINE__);
 391                 return 1;
 392         }
 393
 394         do {
 395                 retval = recv((int)acceptfd, &control, sizeof(char), 0);
 396         } while(retval < sizeof(char));
 397
 398         /* Process the new control message */
 399         switch(control) {
 400                 case TRANS_ABORT:
 401                         if (fixed->nummod > 0)
 402                                 free(modptr);
 403                         /* Unlock objects that was locked due to this transaction */
 404                         for(i = 0; i< transinfo->numlocked; i++) {
 405                                 if((header = mhashSearch(transinfo->objlocked[i])) == NULL) {
 406                                         printf("mhashSearch returns NULL at %s, %d\n", __FILE__, __LINE__);// find the header address
 407                                         return 1;
 408                                 }
 409                                 STATUS(((objheader_t *)header)) &= ~(LOCK);
 410                         }
 411
 412                         /* Send ack to Coordinator */
 413                         sendctrl = TRANS_UNSUCESSFUL;
 414                         if(send((int)acceptfd, &sendctrl, sizeof(char), MSG_NOSIGNAL) < sizeof(char)) {
 415                                 perror("Error: In sending ACK to coordinator\n");
 416                                 if (transinfo->objlocked != NULL) {
 417                                         free(transinfo->objlocked);
 418                                 }
 419                                 if (transinfo->objnotfound != NULL) {
 420                                         free(transinfo->objnotfound);
 421                                 }
 422
 423                                 return 1;
 424                         }
 425                         break;
 426
 427                 case TRANS_COMMIT:
 428                         /* Invoke the transCommit process() */
 429                         if((val = transCommitProcess(modptr, oidmod, transinfo->objlocked, fixed->nummod, transinfo->numlocked, (int)acceptfd)) != 0) {
 430                                 printf("Error: In transCommitProcess() %s, %d\n", __FILE__, __LINE__);
 431                                 /* Free memory */
 432                                 if (transinfo->objlocked != NULL) {
 433                                         free(transinfo->objlocked);
 434                                 }
 435                                 if (transinfo->objnotfound != NULL) {
 436                                         free(transinfo->objnotfound);
 437                                 }
 438                                 return 1;
 439                         }
 440                         break;
 441
 442                 case TRANS_ABORT_BUT_RETRY_COMMIT_WITH_RELOCATING:
 443                         break;
 444                 default:
 445                         printf("Error: No response to TRANS_AGREE OR DISAGREE protocol %s, %d\n", __FILE__, __LINE__);
 446                         //TODO Use fixed.trans_id  TID since Client may have died
 447                         break;
 448         }
 449
 450         /* Free memory */
 451         if (transinfo->objlocked != NULL) {
 452                 free(transinfo->objlocked);
 453         }
 454         if (transinfo->objnotfound != NULL) {
 455                 free(transinfo->objnotfound);
 456         }
 457
 458         return 0;
 459 }
 460
 461 /* This function increments counters while running a voting decision on all objects involved
 462  * in TRANS_REQUEST and If a TRANS_DISAGREE sends the response immediately back to the coordinator */
 463 char handleTransReq(fixed_data_t *fixed, trans_commit_data_t *transinfo, unsigned int *listmid, char *objread, void *modptr, int acceptfd) {
 464         int val, i = 0, j;
 465         unsigned short version;
 466         char control = 0, *ptr;
 467         unsigned int oid;
 468         unsigned int *oidnotfound, *oidlocked;
 469         void *mobj;
 470         objheader_t *headptr;
 471
 472         /* Counters and arrays to formulate decision on control message to be sent */
 473         oidnotfound = (unsigned int *) calloc(fixed->numread + fixed->nummod, sizeof(unsigned int));
 474         oidlocked = (unsigned int *) calloc(fixed->numread + fixed->nummod, sizeof(unsigned int));
 475         int objnotfound = 0, objlocked = 0;
 476         int v_nomatch = 0, v_matchlock = 0, v_matchnolock = 0;
 477
 478         /* modptr points to the beginning of the object store
 479          * created at the Pariticipant.
 480          * Object store holds the modified objects involved in the transaction request */
 481         ptr = (char *) modptr;
 482
 483         /* Process each oid in the machine pile/ group per thread */
 484         for (i = 0; i < fixed->numread + fixed->nummod; i++) {
 485                 if (i < fixed->numread) {//Objs only read and not modified
 486                         int incr = sizeof(unsigned int) + sizeof(unsigned short);// Offset that points to next position in the objread array
 487                         incr *= i;
 488                         oid = *((unsigned int *)(objread + incr));
 489                         incr += sizeof(unsigned int);
 490                         version = *((unsigned short *)(objread + incr));
 491                 } else {//Objs modified
 492                   int tmpsize;
 493                   headptr = (objheader_t *) ptr;
 494                   oid = OID(headptr);
 495                   version = headptr->version;
 496                   GETSIZE(tmpsize, headptr);
 497                   ptr += sizeof(objheader_t) + tmpsize;
 498                 }
 499
 500                 /* Check if object is still present in the machine since the beginning of TRANS_REQUEST */
 501
 502                 if ((mobj = mhashSearch(oid)) == NULL) {/* Obj not found */
 503                         /* Save the oids not found and number of oids not found for later use */
 504                         oidnotfound[objnotfound] = oid;
 505                         objnotfound++;
 506                 } else { /* If Obj found in machine (i.e. has not moved) */
 507                         /* Check if Obj is locked by any previous transaction */
 508                         if ((STATUS(((objheader_t *)mobj)) & LOCK) == LOCK) {
 509                                 if (version == ((objheader_t *)mobj)->version) {      /* If locked then match versions */
 510                                         v_matchlock++;
 511                                 } else {/* If versions don't match ...HARD ABORT */
 512                                         v_nomatch++;
 513                                         /* Send TRANS_DISAGREE to Coordinator */
 514                                         control = TRANS_DISAGREE;
 515                                         if (objlocked > 0) {
 516                                           for(j = 0; j < objlocked; j++) {
 517                                                         if((headptr = mhashSearch(oidlocked[j])) == NULL) {
 518                                                                 printf("mhashSearch returns NULL at %s, %d\n", __FILE__, __LINE__);
 519                                                                 return 0;
 520                                                         }
 521                                                         STATUS(headptr) &= ~(LOCK);
 522                                                 }
 523                                                 free(oidlocked);
 524                                         }
 525                                         if((val = send(acceptfd, &control, sizeof(char), MSG_NOSIGNAL)) < sizeof(char)) {
 526                                                 perror("Error in sending control to the Coordinator\n");
 527                                                 return 0;
 528                                         }
 529                                         return control;
 530                                 }
 531                         } else {/* If Obj is not locked then lock object */
 532                                 STATUS(((objheader_t *)mobj)) |= LOCK;
 533                                 /* Save all object oids that are locked on this machine during this transaction request call */
 534                                 oidlocked[objlocked] = OID(((objheader_t *)mobj));
 535                                 objlocked++;
 536                                 if (version == ((objheader_t *)mobj)->version) { /* Check if versions match */
 537                                         v_matchnolock++;
 538                                 } else { /* If versions don't match ...HARD ABORT */
 539                                         v_nomatch++;
 540                                         control = TRANS_DISAGREE;
 541                                         if (objlocked > 0) {
 542                                                 for(j = 0; j < objlocked; j++) {
 543                                                         if((headptr = mhashSearch(oidlocked[j])) == NULL) {
 544                                                                 printf("mhashSearch returns NULL at %s, %d\n", __FILE__, __LINE__);
 545                                                                 return 0;
 546                                                         }
 547                                                         STATUS(headptr) &= ~(LOCK);
 548                                                 }
 549                                                 free(oidlocked);
 550                                         }
 551
 552                                         /* Send TRANS_DISAGREE to Coordinator */
 553                                         if((val = send(acceptfd, &control, sizeof(char), MSG_NOSIGNAL)) < sizeof(char)) {
 554                                                 perror("Error in sending control to the Coordinator\n");
 555                                                 return 0;
 556                                         }
 557
 558                                         return control;
 559                                 }
 560                         }
 561                 }
 562         }
 563
 564         /* Decide what control message to send to Coordinator */
 565         if ((control = decideCtrlMessage(fixed, transinfo, &v_matchnolock, &v_matchlock, &v_nomatch, &objnotfound, &objlocked,
 566                                         modptr, oidnotfound, oidlocked, acceptfd)) == 0) {
 567                 printf("Error: In decideCtrlMessage() %s, %d\n", __FILE__, __LINE__);
 568                 return 0;
 569         }
 570
 571         return control;
 572
 573 }
 574 /* This function decides what control message such as TRANS_AGREE, TRANS_DISAGREE or TRANS_SOFT_ABORT
 575  * to send to Coordinator based on the votes of oids involved in the transaction */
 576 char decideCtrlMessage(fixed_data_t *fixed, trans_commit_data_t *transinfo, int *v_matchnolock, int *v_matchlock,
 577                 int *v_nomatch, int *objnotfound, int *objlocked, void *modptr,
 578                 unsigned int *oidnotfound, unsigned int *oidlocked, int acceptfd) {
 579         int val;
 580         char control = 0;
 581
 582         /* Condition to send TRANS_AGREE */
 583         if(*(v_matchnolock) == fixed->numread + fixed->nummod) {
 584                 control = TRANS_AGREE;
 585                 /* Send control message */
 586                 if((val = send(acceptfd, &control, sizeof(char), MSG_NOSIGNAL)) < sizeof(char)) {
 587                         perror("Error in sending control to Coordinator\n");
 588                         return 0;
 589                 }
 590         }
 591         /* Condition to send TRANS_SOFT_ABORT */
 592         if((*(v_matchlock) > 0 && *(v_nomatch) == 0) || (*(objnotfound) > 0 && *(v_nomatch) == 0)) {
 593                 control = TRANS_SOFT_ABORT;
 594
 595                 /* Send control message */
 596                 if((val = send(acceptfd, &control, sizeof(char),MSG_NOSIGNAL)) < sizeof(char)) {
 597                         perror("Error in sending TRANS_SOFT_ABORT control\n");
 598                         return 0;
 599                 }
 600
 601                 /* Send number of oids not found and the missing oids if objects are missing in the machine */
 602                 if(*(objnotfound) != 0) {
 603                         int msg[1];
 604                         msg[0] = *(objnotfound);
 605                         if((val = send(acceptfd, msg, sizeof(int) ,MSG_NOSIGNAL)) < sizeof(int)) {
 606                                 perror("Error in sending objects that are not found\n");
 607                                 return 0;
 608                         }
 609                         int size = sizeof(unsigned int)* *(objnotfound);
 610                         if((val = send(acceptfd, oidnotfound, size ,MSG_NOSIGNAL)) < size) {
 611                                 perror("Error in sending objects that are not found\n");
 612                                 return 0;
 613                         }
 614                 }
 615         }
 616
 617         /* Fill out the trans_commit_data_t data structure. This is required for a trans commit process
 618          * if Participant receives a TRANS_COMMIT */
 619         transinfo->objlocked = oidlocked;
 620         transinfo->objnotfound = oidnotfound;
 621         transinfo->modptr = modptr;
 622         transinfo->numlocked = *(objlocked);
 623         transinfo->numnotfound = *(objnotfound);
 624
 625         return control;
 626 }
 627
 628 /* This function processes all modified objects involved in a TRANS_COMMIT and updates pointer
 629  * addresses in lookup table and also changes version number
 630  * Sends an ACK back to Coordinator */
 631 int transCommitProcess(void *modptr, unsigned int *oidmod, unsigned int *oidlocked, int nummod, int numlocked, int acceptfd) {
 632         objheader_t *header;
 633         objheader_t *newheader;
 634         int i = 0, offset = 0;
 635         char control;
 636         int tmpsize;
 637
 638         /* Process each modified object saved in the mainobject store */
 639         for(i = 0; i < nummod; i++) {
 640                 if((header = (objheader_t *) mhashSearch(oidmod[i])) == NULL) {
 641                         printf("Error: mhashsearch returns NULL at %s, %d\n", __FILE__, __LINE__);
 642                         return 1;
 643                 }
 644                 GETSIZE(tmpsize,header);
 645                 pthread_mutex_lock(&mainobjstore_mutex);
 646                 memcpy((char*)header + sizeof(objheader_t), ((char *)modptr + sizeof(objheader_t) + offset), tmpsize);
 647                 header->version += 1;
 648                 /* If threads are waiting on this object to be updated, notify them */
 649                 if(header->notifylist != NULL) {
 650                         notifyAll(&header->notifylist, OID(header), header->version);
 651                 }
 652                 pthread_mutex_unlock(&mainobjstore_mutex);
 653                 offset += sizeof(objheader_t) + tmpsize;
 654         }
 655
 656         if (nummod > 0)
 657                 free(modptr);
 658
 659         /* Unlock locked objects */
 660         for(i = 0; i < numlocked; i++) {
 661                 if((header = (objheader_t *) mhashSearch(oidlocked[i])) == NULL) {
 662                         printf("Error: mhashsearch returns NULL at %s, %d\n", __FILE__, __LINE__);
 663                         return 1;
 664                 }
 665                 STATUS(header) &= ~(LOCK);
 666         }
 667         //TODO Update location lookup table
 668
 669         /* Send ack to coordinator */
 670         control = TRANS_SUCESSFUL;
 671         if(send((int)acceptfd, &control, sizeof(char), MSG_NOSIGNAL) < sizeof(char)) {
 672                 perror("Error sending ACK to coordinator\n");
 673                 return 1;
 674         }
 675
 676         return 0;
 677 }
 678
 679 /* This function recevies the oid and offset tuples from the Coordinator's prefetch call.
 680  * Looks for the objects to be prefetched in the main object store.
 681  * If objects are not found then record those and if objects are found
 682  * then use offset values to prefetch references to other objects */
 683
 684 int prefetchReq(int acceptfd) {
 685         int i, size, objsize, numbytes = 0, isArray = 0, numoffset = 0;
 686         int length, sd;
 687         char *recvbuffer, *sendbuffer, control;
 688         unsigned int oid, mid;
 689         short *offsetarry;
 690         objheader_t *header;
 691         struct sockaddr_in remoteAddr;
 692
 693         while((numbytes = recv((int)acceptfd, &length, sizeof(int), 0)) != 0) {
 694                 if(length == -1) { //-1 is special character to represent end of sending oids and offsets
 695                         break;
 696                 } else {
 697                         numbytes = 0;
 698                         size = length - sizeof(int);
 699                         if((recvbuffer = calloc(1, size)) == NULL) {
 700                                 printf("Calloc error at %s,%d\n", __FILE__, __LINE__);
 701                                 return -1;
 702                         }
 703                         while(numbytes < size) {
 704                                 numbytes += recv((int)acceptfd, recvbuffer+numbytes, size-numbytes, 0);
 705                         }
 706
 707                         oid = *((unsigned int *) recvbuffer);
 708                         mid = *((unsigned int *) (recvbuffer + sizeof(unsigned int)));
 709                         size = size - (2 * sizeof(unsigned int));
 710                         numoffset = size / sizeof(short);
 711                         if((offsetarry = calloc(numoffset, sizeof(short))) == NULL) {
 712                                 printf("Calloc error at %s,%d\n", __FILE__, __LINE__);
 713                                 free(recvbuffer);
 714                                 return -1;
 715                         }
 716                         memcpy(offsetarry, recvbuffer + (2 * sizeof(unsigned int)), size);
 717                         free(recvbuffer);
 718
 719                         /* Create socket to send information */
 720                         if ((sd = socket(AF_INET, SOCK_STREAM, 0)) < 0){
 721                                 perror("prefetchReq():socket()");
 722                                 return -1;
 723                         }
 724                         bzero(&remoteAddr, sizeof(remoteAddr));
 725                         remoteAddr.sin_family = AF_INET;
 726                         remoteAddr.sin_port = htons(LISTEN_PORT);
 727                         remoteAddr.sin_addr.s_addr = htonl(mid);
 728
 729                         if (connect(sd, (struct sockaddr *)&remoteAddr, sizeof(remoteAddr)) < 0){
 730                                 printf("Error: prefetchReq():error %d connecting to %s:%d\n", errno,
 731                                                 inet_ntoa(remoteAddr.sin_addr), LISTEN_PORT);
 732                                 close(sd);
 733                                 return -1;
 734                         }
 735
 736                         /*Process each oid */
 737                         if ((header = mhashSearch(oid)) == NULL) {/* Obj not found */
 738                                 /* Save the oids not found in buffer for later use */
 739                                 size = sizeof(int) + sizeof(char) + sizeof(unsigned int) ;
 740                                 if((sendbuffer = calloc(1, size)) == NULL) {
 741                                         printf("Calloc error at %s,%d\n", __FILE__, __LINE__);
 742                                         free(offsetarry);
 743                                         close(sd);
 744                                         return -1;
 745                                 }
 746                                 *((int *) sendbuffer) = size;
 747                                 *((char *)(sendbuffer + sizeof(int))) = OBJECT_NOT_FOUND;
 748                                 *((unsigned int *)(sendbuffer + sizeof(int) + sizeof(char))) = oid;
 749
 750                                 control = TRANS_PREFETCH_RESPONSE;
 751                                 if(sendPrefetchResponse(sd, &control, sendbuffer, &size) != 0) {
 752                                         free(offsetarry);
 753                                         printf("Error: %s() in sending prefetch response at %s, %d\n",
 754                                                         __func__, __FILE__, __LINE__);
 755                                         close(sd);
 756                                         return -1;
 757                                 }
 758                         } else { /* Object Found */
 759                                 int incr = 0;
 760                                 GETSIZE(objsize, header);
 761                                 size = sizeof(int) + sizeof(char) + sizeof(unsigned int) + sizeof(objheader_t) + objsize;
 762                                 if((sendbuffer = calloc(1, size)) == NULL) {
 763                                         printf("Calloc error at %s,%d\n", __FILE__, __LINE__);
 764                                         free(offsetarry);
 765                                         close(sd);
 766                                         return -1;
 767                                 }
 768                                 *((int *) (sendbuffer + incr)) = size;
 769                                 incr += sizeof(int);
 770                                 *((char *)(sendbuffer + incr)) = OBJECT_FOUND;
 771                                 incr += sizeof(char);
 772                                 *((unsigned int *)(sendbuffer+incr)) = oid;
 773                                 incr += sizeof(unsigned int);
 774                                 memcpy(sendbuffer + incr, header, objsize + sizeof(objheader_t));
 775
 776                                 control = TRANS_PREFETCH_RESPONSE;
 777                                 if(sendPrefetchResponse(sd, &control, sendbuffer, &size) != 0) {
 778                                         free(offsetarry);
 779                                         printf("Error: %s() in sending prefetch response at %s, %d\n",
 780                                                         __func__, __FILE__, __LINE__);
 781                                         close(sd);
 782                                         return -1;
 783                                 }
 784                                 /* Calculate the oid corresponding to the offset value */
 785                                 for(i = 0 ; i< numoffset ; i++) {
 786                                         /* Check for arrays  */
 787                                         if(TYPE(header) > NUMCLASSES) {
 788                                                 isArray = 1;
 789                                         }
 790                                         if(isArray == 1) {
 791                                                 int elementsize = classsize[TYPE(header)];
 792                                                 struct ArrayObject *ao = (struct ArrayObject *) (((char *)header) + sizeof(objheader_t));
 793                                                 unsigned short length = ao->___length___;
 794                                                 /* Check if array out of bounds */
 795                                                 if(offsetarry[i]< 0 || offsetarry[i] >= length) {
 796                                                         break;
 797                                                 }
 798                                                 oid = *((unsigned int *)(((char *)header) + sizeof(objheader_t) + sizeof(struct ArrayObject) + (elementsize*offsetarry[i])));
 799                                         } else {
 800                                                 oid = *((unsigned int *)(((char *)header) + sizeof(objheader_t) + offsetarry[i]));
 801                                         }
 802
 803                                         if((header = mhashSearch(oid)) == NULL) {
 804                                                 size = sizeof(int) + sizeof(char) + sizeof(unsigned int) ;
 805                                                 if((sendbuffer = calloc(1, size)) == NULL) {
 806                                                         printf("Calloc error at %s,%d\n", __FILE__, __LINE__);
 807                                                         free(offsetarry);
 808                                                         close(sd);
 809                                                         return -1;
 810                                                 }
 811                                                 *((int *) sendbuffer) = size;
 812                                                 *((char *)(sendbuffer + sizeof(int))) = OBJECT_NOT_FOUND;
 813                                                 *((unsigned int *)(sendbuffer + sizeof(int) + sizeof(char))) = oid;
 814
 815                                                 control = TRANS_PREFETCH_RESPONSE;
 816                                                 if(sendPrefetchResponse(sd, &control, sendbuffer, &size) != 0) {
 817                                                         free(offsetarry);
 818                                                         printf("Error: %s() in sending prefetch response at %s, %d\n",
 819                                                                         __FILE__, __LINE__);
 820                                                         close(sd);
 821                                                         return -1;
 822                                                 }
 823                                                 break;
 824                                         } else {/* Obj Found */
 825                                                 int incr = 0;
 826                                                 GETSIZE(objsize, header);
 827                                                 size = sizeof(int) + sizeof(char) + sizeof(unsigned int) + sizeof(objheader_t) + objsize;
 828                                                 if((sendbuffer = calloc(1, size)) == NULL) {
 829                                                         printf("Calloc error at %s,%d\n", __func__, __FILE__, __LINE__);
 830                                                         free(offsetarry);
 831                                                         close(sd);
 832                                                         return -1;
 833                                                 }
 834                                                 *((int *) (sendbuffer + incr)) = size;
 835                                                 incr += sizeof(int);
 836                                                 *((char *)(sendbuffer + incr)) = OBJECT_FOUND;
 837                                                 incr += sizeof(char);
 838                                                 *((unsigned int *)(sendbuffer+incr)) = oid;
 839                                                 incr += sizeof(unsigned int);
 840                                                 memcpy(sendbuffer + incr, header, objsize + sizeof(objheader_t));
 841
 842                                                 control = TRANS_PREFETCH_RESPONSE;
 843                                                 if(sendPrefetchResponse(sd, &control, sendbuffer, &size) != 0) {
 844                                                         free(offsetarry);
 845                                                         printf("Error: %s() in sending prefetch response at %s, %d\n",
 846                                                                         __func__, __FILE__, __LINE__);
 847                                                         close(sd);
 848                                                         return -1;
 849                                                 }
 850                                         }
 851                                         isArray = 0;
 852                                 }
 853                                 free(offsetarry);
 854                         }
 855                 }
 856         }
 857         close(sd);
 858         return 0;
 859 }
 860
 861 int sendPrefetchResponse(int sd, char *control, char *sendbuffer, int *size) {
 862         int numbytes = 0;
 863
 864         if((numbytes = send(sd, control, sizeof(char), MSG_NOSIGNAL)) < sizeof(char)) {
 865                 printf("%s() Error: in sending PREFETCH RESPONSE to Coordinator at %s, %d\n", __func__, __FILE__, __LINE__);
 866                 free(sendbuffer);
 867                 return -1;
 868         }
 869
 870         /* Send the buffer with its size */
 871         if((numbytes = send(sd, sendbuffer, *(size), MSG_NOSIGNAL)) < *(size)) {
 872                 printf("%s() Error: in sending oid found at %s, %d size sent = %d, actual size = %d\n",
 873                                 __func__, __FILE__, __LINE__, numbytes, *(size));
 874                 free(sendbuffer);
 875                 return -1;
 876         }
 877
 878         free(sendbuffer);
 879         return 0;
 880 }
 881
 882 void processReqNotify(unsigned int numoid, unsigned int *oidarry, unsigned short *versionarry, unsigned int mid, unsigned int threadid) {
 883         objheader_t *header;
 884         unsigned int oid;
 885         unsigned short newversion;
 886         char msg[1+  2 * sizeof(unsigned int) + sizeof(unsigned short)];
 887         int sd;
 888         struct sockaddr_in remoteAddr;
 889         int bytesSent;
 890         int size;
 891
 892         int i = 0;
 893         while(i < numoid) {
 894                 oid = *(oidarry + i);
 895                 if((header = (objheader_t *) mhashSearch(oid)) == NULL) {
 896                         printf("Error: mhashsearch returns NULL at %s, %d\n", __FILE__, __LINE__);
 897                         return;
 898                 } else {
 899                         /* Check to see if versions are same */
 900 checkversion:
 901                         if ((STATUS(header) & LOCK) != LOCK) {
 902                                 //FIXME make locking atomic
 903                                 STATUS(header) |= LOCK;
 904                                 newversion = header->version;
 905                                 if(newversion == *(versionarry + i)) {
 906                                         //Add to the notify list
 907                                         if((header->notifylist = insNode(header->notifylist, threadid, mid)) == NULL) {
 908                                                 printf("Error: Obj notify list points to NULL %s, %d\n", __FILE__, __LINE__);
 909                                                 return;
 910                                         }
 911                                         STATUS(header) &= ~(LOCK);
 912                                 } else {
 913                                         STATUS(header) &= ~(LOCK);
 914                                         if ((sd = socket(AF_INET, SOCK_STREAM, 0)) < 0){
 915                                                 perror("processReqNotify():socket()");
 916                                                 return;
 917                                         }
 918                                         bzero(&remoteAddr, sizeof(remoteAddr));
 919                                         remoteAddr.sin_family = AF_INET;
 920                                         remoteAddr.sin_port = htons(LISTEN_PORT);
 921                                         remoteAddr.sin_addr.s_addr = htonl(mid);
 922
 923                                         if (connect(sd, (struct sockaddr *)&remoteAddr, sizeof(remoteAddr)) < 0){
 924                                                 printf("Error: processReqNotify():error %d connecting to %s:%d\n", errno,
 925                                                                 inet_ntoa(remoteAddr.sin_addr), LISTEN_PORT);
 926                                                 close(sd);
 927                                                 return;
 928                                         } else {
 929                                                 //Send Update notification
 930                                                 msg[0] = THREAD_NOTIFY_RESPONSE;
 931                                                 *((unsigned int *)&msg[1]) = oid;
 932                                                 size = sizeof(unsigned int);
 933                                                 *((unsigned short *)(&msg[1]+size)) = newversion;
 934                                                 size += sizeof(unsigned short);
 935                                                 *((unsigned int *)(&msg[1]+size)) = threadid;
 936                                                 bytesSent = send(sd, msg, 1+ 2*sizeof(unsigned int) + sizeof(unsigned short), 0);
 937                                                 if (bytesSent < 0){
 938                                                         perror("processReqNotify():send()");
 939                                                         close(sd);
 940                                                         return;
 941                                                 } else if (bytesSent != 1 + sizeof(unsigned short) + 2*sizeof(unsigned int)){
 942                                                         printf("Error: processReqNotify(): error, sent %d bytes %s, %d\n",
 943                                                                         bytesSent, __FILE__, __LINE__);
 944                                                         close(sd);
 945                                                         return;
 946                                                 } else {
 947                                                         close(sd);
 948                                                         return;
 949                                                 }
 950
 951                                         }
 952                                         close(sd);
 953                                 }
 954                         } else {
 955                                 randomdelay();
 956                                 goto checkversion;
 957                         }
 958                 }
 959                 i++;
 960         }
 961         free(oidarry);
 962         free(versionarry);
 963 }
 964