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