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

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <string.h>
   4 #include <pthread.h>
   5 #include <netdb.h>
   6 #include <fcntl.h>
   7 #include "dstm.h"
   8 #include "mlookup.h"
   9 #include "llookup.h"
  10
  11 #define LISTEN_PORT 2156
  12 #define BACKLOG 10 //max pending connections
  13 #define RECEIVE_BUFFER_SIZE 2048
  14
  15 extern int classsize[];
  16
  17 objstr_t *mainobjstore;
  18
  19 int dstmInit(void)
  20 {
  21         //Initialize main object store
  22         mainobjstore = objstrCreate(DEFAULT_OBJ_STORE_SIZE);
  23         if (mhashCreate(HASH_SIZE, LOADFACTOR))
  24                 return 1; //failure
  25
  26         if (lhashCreate(HASH_SIZE, LOADFACTOR))
  27                 return 1; //failure
  28
  29         //pthread_t threadListen;
  30         //pthread_create(&threadListen, NULL, dstmListen, NULL);
  31
  32         return 0;
  33 }
  34
  35 void *dstmListen()
  36 {
  37         int listenfd, acceptfd;
  38         struct sockaddr_in my_addr;
  39         struct sockaddr_in client_addr;
  40         socklen_t addrlength = sizeof(struct sockaddr);
  41         pthread_t thread_dstm_accept;
  42         int i;
  43
  44         listenfd = socket(AF_INET, SOCK_STREAM, 0);
  45         if (listenfd == -1)
  46         {
  47                 perror("socket");
  48                 exit(1);
  49         }
  50
  51         my_addr.sin_family = AF_INET;
  52         my_addr.sin_port = htons(LISTEN_PORT);
  53         my_addr.sin_addr.s_addr = INADDR_ANY;
  54         memset(&(my_addr.sin_zero), '\0', 8);
  55
  56         if (bind(listenfd, (struct sockaddr *)&my_addr, addrlength) == -1)
  57         {
  58                 perror("bind");
  59                 exit(1);
  60         }
  61
  62         if (listen(listenfd, BACKLOG) == -1)
  63         {
  64                 perror("listen");
  65                 exit(1);
  66         }
  67
  68         printf("Listening on port %d, fd = %d\n", LISTEN_PORT, listenfd);
  69         while(1)
  70         {
  71                 acceptfd = accept(listenfd, (struct sockaddr *)&client_addr, &addrlength);
  72                 pthread_create(&thread_dstm_accept, NULL, dstmAccept, (void *)acceptfd);
  73         }
  74         pthread_exit(NULL);
  75 }
  76
  77 void *dstmAccept(void *acceptfd)
  78 {
  79         int numbytes,i, val;
  80         unsigned int oid;
  81         char buffer[RECEIVE_BUFFER_SIZE], control,ctrl;
  82         char *ptr;
  83         void *srcObj;
  84         objheader_t *h;
  85         trans_commit_data_t transinfo;
  86
  87         int fd_flags = fcntl((int)acceptfd, F_GETFD), size;
  88
  89         printf("Recieved connection: fd = %d\n", (int)acceptfd);
  90         recv((int)acceptfd, &control, sizeof(char), 0);
  91         switch(control) {
  92                 case READ_REQUEST:
  93                         printf("DEBUG -> Recv READ_REQUEST from Coordinator\n");
  94                         recv((int)acceptfd, &oid, sizeof(unsigned int), 0);
  95                         srcObj = mhashSearch(oid);
  96                         h = (objheader_t *) srcObj;
  97                         size = sizeof(objheader_t) + sizeof(classsize[h->type]);
  98                         if (h == NULL) {
  99                                 ctrl = OBJECT_NOT_FOUND;
 100                                 if(send((int)acceptfd, &ctrl, sizeof(char), 0) < 0) {
 101                                         perror("Error sending control msg to coordinator\n");
 102                                 }
 103                         } else {
 104                                 //char responsemessage[sizeof(char)+sizeof(int)];
 105                                 /* Type */
 106                                 ctrl = OBJECT_FOUND;
 107                                 if(send((int)acceptfd, &ctrl, sizeof(char), 0) < 0) {
 108                                         perror("Error sending control msg to coordinator\n");
 109                                 }
 110
 111                                 //responsemessage[0]=OBJECT_FOUND;
 112                                 /* Size of object */
 113                                 //*((int *)(&responsemessage[1])) = sizeof(objheader_t) + classsize[h->type];
 114                                 //if(send((int)acceptfd, &responsemessage, sizeof(responsemessage), 0) < 0) {
 115                                 //      perror("Error sending control msg to coordinator\n");
 116                                 //}
 117
 118                                 /* Size of object */
 119                                 if(send((int)acceptfd, &size, sizeof(int), 0) < 0) {
 120                                         perror("Error sending size of object to coordinator\n");
 121                                 }
 122                                 if(send((int)acceptfd, h, size, 0) < 0) {
 123                                         perror("Error in sending object\n");
 124                                 }
 125                         }
 126                         break;
 127
 128                 case READ_MULT_REQUEST:
 129                         printf("DEBUG-> READ_MULT_REQUEST\n");
 130                         break;
 131
 132                 case MOVE_REQUEST:
 133                         printf("DEBUG -> MOVE_REQUEST\n");
 134                         break;
 135
 136                 case MOVE_MULT_REQUEST:
 137                         printf("DEBUG -> MOVE_MULT_REQUEST\n");
 138                         break;
 139
 140                 case TRANS_REQUEST:
 141                         printf("DEBUG -> Recv TRANS_REQUEST from Coordinator\n");
 142                         if((val = readClientReq((int)acceptfd, &transinfo)) != 0) {
 143                                 printf("Error in readClientReq\n");
 144                         }
 145                         break;
 146
 147                 default:
 148                         printf("Error receiving\n");
 149         }
 150         if (close((int)acceptfd) == -1)
 151         {
 152                 perror("close");
 153         }
 154         else
 155                 printf("Closed connection: fd = %d\n", (int)acceptfd);
 156
 157         //Free memory
 158         free(transinfo.objmod);
 159         free(transinfo.objlocked);
 160         free(transinfo.objnotfound);
 161         pthread_exit(NULL);
 162 }
 163
 164 int readClientReq(int acceptfd, trans_commit_data_t *transinfo) {
 165         char *ptr, control, prevctrl, sendctrl, newctrl;
 166         void *modptr, *header;
 167         objheader_t *tmp_header;
 168         fixed_data_t fixed;
 169         int sum = 0, i, N, n, val;
 170
 171         //Reads to process the TRANS_REQUEST protocol further
 172         // Read fixed_data
 173         N = sizeof(fixed) - 1;
 174         ptr = (char *)&fixed;;
 175         fixed.control = TRANS_REQUEST;
 176         do {
 177                 n = recv((int)acceptfd, (void *) ptr+1+sum, N-sum, 0);
 178         //      printf("DEBUG -> 1. Reading %d bytes \n", n);
 179                 sum += n;
 180         } while(sum < N && n != 0);
 181
 182         //printf("Machine count = %d\tnumread = %d\tnummod = %d\tsum_bytes = %d\n", fixed.mcount, fixed.numread, fixed.nummod, fixed.sum_bytes);
 183         // Read list of mids
 184         int mcount = fixed.mcount;
 185         N = mcount * sizeof(unsigned int);
 186         unsigned int listmid[mcount];
 187         ptr = (char *) listmid;
 188         sum = 0;
 189         do {
 190                 n = recv((int)acceptfd, (void *) ptr+sum, N-sum, 0);
 191         //      printf("DEBUG -> 2. Reading %d bytes cap = %d\n", n, N);
 192                 sum += n;
 193         } while(sum < N && n != 0);
 194
 195         // Read oid and version tuples
 196         int numread = fixed.numread;
 197         N = numread * (sizeof(unsigned int) + sizeof(short));
 198         char objread[N];
 199         sum = 0;
 200         do {
 201                 n = recv((int)acceptfd, (void *) objread, N, 0);
 202         //      printf("DEBUG -> 3. Reading %d bytes cap = %d\n", n, N);
 203                 sum += n;
 204         } while(sum < N && n != 0);
 205         //printf("DEBUG -> %d %d %d %d\n", *objread, *(objread + 6), *(objread + 12), *(objread + 18));
 206
 207         // Read modified objects
 208         if ((modptr = objstrAlloc(mainobjstore, fixed.sum_bytes)) == NULL) {
 209                 printf("objstrAlloc error for modified objects %s, %d", __FILE__, __LINE__);
 210                 return 1;
 211         }
 212         sum = 0;
 213         do {
 214                 n = recv((int)acceptfd, modptr+sum, fixed.sum_bytes-sum, 0);
 215                 //printf("DEBUG -> 4. Reading %d bytes cap = %d, oid = %d\n", n, fixed.sum_bytes, *((int *)modptr));
 216                 sum += n;
 217         } while (sum < fixed.sum_bytes && n != 0);
 218
 219         //Send control message as per all votes from all oids in the machine
 220         if((prevctrl = handleTransReq(acceptfd, &fixed, transinfo, listmid, objread, modptr)) == 0 ) {
 221                 printf("Handle req error\n");
 222         }
 223
 224         //Read for new control message from Coordiator
 225         recv((int)acceptfd, &control, sizeof(char), 0);
 226         switch(control) {
 227                 case TRANS_ABORT:
 228                         printf("DEBUG -> Recv TRANS_ABORT from Coordinator\n");
 229                         //send ack to coordinator
 230                         sendctrl = TRANS_SUCESSFUL;
 231                         if(send((int)acceptfd, &sendctrl, sizeof(char), 0) < 0) {
 232                                 perror("Error sending ACK to coordinator\n");
 233                         }
 234                         //Mark all ref counts as 1 and do garbage collection
 235                         ptr = modptr;
 236                         for(i = 0; i< fixed.nummod; i++) {
 237                                 tmp_header = (objheader_t *)ptr;
 238                                 tmp_header->rcount = 1;
 239                                 ptr += sizeof(objheader_t) + classsize[tmp_header->type];
 240                         }
 241                         //Unlock objects that was locked in this machine due to this transaction
 242                         for(i = 0; i< transinfo->numlocked; i++) {
 243                                 header = mhashSearch(transinfo->objlocked[i]);// find the header address
 244                                 ((objheader_t *)header)->status &= ~(LOCK);
 245                         }
 246                         ptr = NULL;
 247                         return 0;
 248
 249                 case TRANS_COMMIT:
 250                         printf("DEBUG -> Recv TRANS_COMMIT from Coordinator\n");
 251                         if((val = transCommitProcess(transinfo, (int)acceptfd)) != 0) {
 252                                 printf("Error in transCommitProcess %s, %d\n", __FILE__, __LINE__);
 253                         }
 254                         break;
 255                 case TRANS_ABORT_BUT_RETRY_COMMIT:
 256                         printf("DEBUG -> Recv TRANS_ABORT_BUT_RETRY_COMMIT from Coordinator\n");
 257                         //Process again after waiting for sometime and on prev control message sent
 258                         switch(prevctrl) {
 259                                 case TRANS_AGREE:
 260                                         sendctrl = TRANS_AGREE;
 261                                         if(send((int)acceptfd, &sendctrl, sizeof(char), 0) < 0) {
 262                                                 perror("Error sending ACK to coordinator\n");
 263                                         }
 264                                         sleep(5);
 265                                         break;
 266                                 case TRANS_SOFT_ABORT:
 267                                         if((newctrl = handleTransReq(acceptfd, &fixed, transinfo, listmid, objread, modptr)) == 0 ) {
 268                                                 printf("Handle req error\n");
 269                                         }
 270                                         if(newctrl == prevctrl){
 271                                                 //Send ABORT
 272                                                 newctrl = TRANS_DISAGREE;
 273                                                 if(send((int)acceptfd, &newctrl, sizeof(char), 0) < 0) {
 274                                                         perror("Error sending ACK to coordinator\n");
 275                                                 }
 276                                                 //Set the reference count of the object to 1 in mainstore for garbage collection
 277                                                 ptr = modptr;
 278                                                 for(i = 0; i< fixed.nummod; i++) {
 279                                                         tmp_header = (objheader_t *) ptr;
 280                                                         tmp_header->rcount = 1;
 281                                                         ptr += sizeof(objheader_t) + classsize[tmp_header->type];
 282                                                 }
 283                                                 //Unlock objects that was locked in this machine due to this transaction
 284                                                 for(i = 0; i< transinfo->numlocked; i++) {
 285                                                         ptr = mhashSearch(transinfo->objlocked[i]);// find the header address
 286                                                         ((objheader_t *)ptr)->status &= ~(LOCK);
 287                                                 }
 288                                                 return 0;
 289                                         } else {
 290                                                 //Send new control message
 291                                                 if(send((int)acceptfd, &newctrl, sizeof(char), 0) < 0) {
 292                                                         perror("Error sending ACK to coordinator\n");
 293                                                 }
 294                                         }
 295
 296                                         break;
 297                         }
 298
 299                         break;
 300                 case TRANS_ABORT_BUT_RETRY_COMMIT_WITH_RELOCATING:
 301                         //TODO expect another transrequest from client
 302                         printf("DEBUG -> Recv TRANS_ABORT_BUT_RETRY_COMMIT_WITH_RELOCATING from Coordinator\n");
 303                         break;
 304                 default:
 305                         printf("No response to TRANS_AGREE OR DISAGREE protocol\n");
 306                         //TODO Use fixed.trans_id  TID since Client may have died
 307                         break;
 308         }
 309
 310         return 0;
 311 }
 312
 313 //This function runs a decision after all objects are weighed under one of the 4 possibilities
 314 //and returns the appropriate control message to the Ccordinator
 315 char handleTransReq(int acceptfd, fixed_data_t *fixed, trans_commit_data_t *transinfo, unsigned int *listmid, char *objread, void *modptr) {
 316         short version;
 317         char control = 0, ctrlmissoid, *ptr;
 318         int i, j = 0;
 319         unsigned int oid;
 320         unsigned int *oidnotfound, *oidlocked, *oidmod;
 321
 322         oidnotfound = (unsigned int *) calloc(fixed->numread + fixed->nummod, sizeof(unsigned int));
 323         oidlocked = (unsigned int *) calloc(fixed->numread + fixed->nummod, sizeof(unsigned int));
 324         oidmod = (unsigned int *) calloc(fixed->nummod, sizeof(unsigned int));
 325
 326         // Counters and arrays to formulate decision on control message to be sent
 327         int objnotfound = 0, objlocked = 0, objmod =0, v_nomatch = 0, v_matchlock = 0, v_matchnolock = 0;
 328         int objmodnotfound = 0, nummodfound = 0;
 329         void *mobj;
 330         objheader_t *headptr;
 331
 332         //Process each object present in the pile
 333         ptr = modptr;
 334         printf("DEBUG -> Total objs involved in trans is %d\n",fixed->nummod + fixed->numread);
 335         fflush(stdout);
 336         //Process each oid in the machine pile/ group
 337         for (i = 0; i < fixed->numread + fixed->nummod; i++) {
 338                 if (i < fixed->numread) {//Object is read
 339                         int incr = sizeof(unsigned int) + sizeof(short);// Offset that points to next position in the objread array
 340                         incr *= i;
 341                         oid = *((unsigned int *)(objread + incr));
 342                         incr += sizeof(unsigned int);
 343                         version = *((short *)(objread + incr));
 344                 } else {//Obj is modified
 345                         headptr = (objheader_t *) ptr;
 346                         oid = headptr->oid;
 347                         oidmod[objmod] = oid;//Array containing modified oids
 348                         objmod++;
 349                         version = headptr->version;
 350                         ptr += sizeof(objheader_t) + classsize[headptr->type];
 351                 }
 352                 //Check if object is still present in the machine since the beginning of TRANS_REQUEST
 353                 if ((mobj = mhashSearch(oid)) == NULL) {// Obj not found
 354                         //Save the oids not found for later use
 355                         oidnotfound[objnotfound] = ((objheader_t *)mobj)->oid;
 356                         objnotfound++;
 357                 } else { // If obj found in machine (i.e. has not moved)
 358                         //Check if obj is locked
 359                         if ((((objheader_t *)mobj)->status & LOCK) == LOCK) {
 360                                 if (version == ((objheader_t *)mobj)->version) {      // If version match
 361                                         v_matchlock++;
 362                                 } else {//If versions don't match ..HARD ABORT
 363                                         v_nomatch++;
 364                                         //send TRANS_DISAGREE to Coordinator
 365                                         control = TRANS_DISAGREE;
 366                                         write(acceptfd, &control, sizeof(char));
 367                                         printf("DEBUG -> Sending TRANS_DISAGREE\n");
 368                                         return control;
 369                                 }
 370                         } else {//Obj is not locked , so lock object
 371                                 ((objheader_t *)mobj)->status |= LOCK;
 372                                 //Save all object oids that are locked on this machine during this transaction request call
 373                                 oidlocked[objlocked] = ((objheader_t *)mobj)->oid;
 374                                 printf("DEBUG-> Object to be locked is %d\n", ((objheader_t *)mobj)->oid);
 375                                 objlocked++;
 376                                 if (version == ((objheader_t *)mobj)->version) { //If versions match
 377                                         v_matchnolock++;
 378                                 } else { //If versions don't match
 379                                         v_nomatch++;
 380                                         //send TRANS_DISAGREE to Coordinator
 381                                         control = TRANS_DISAGREE;
 382                                         write(acceptfd, &control, sizeof(char));
 383                                         printf("DEBUG -> Sending TRANS_DISAGREE\n");
 384                                         return control;
 385                                 }
 386                         }
 387                 }
 388         }
 389
 390         printf("No of objs locked = %d\n", objlocked);
 391         printf("No of v_nomatch = %d\n", v_nomatch);
 392         printf("No of objs v_match but are did not have locks before = %d\n", v_matchnolock);
 393         printf("No of objs v_match but had locks before = %d\n", v_matchlock);
 394         printf("No of objs not found = %d\n", objnotfound);
 395         printf("No of objs modified but not found = %d\n", objmodnotfound);
 396
 397         //Decide what control message(s) to send
 398         if(v_matchnolock == fixed->numread + fixed->nummod) {
 399                 //send TRANS_AGREE to Coordinator
 400                 control = TRANS_AGREE;
 401                 write(acceptfd, &control, sizeof(char));
 402                 printf("DEBUG -> Sending TRANS_AGREE\n");
 403         }
 404
 405         if((v_matchlock > 0 && v_nomatch == 0) || (objnotfound > 0 && v_nomatch == 0)) {
 406                 //send TRANS_SOFT_ABORT to Coordinator
 407                 control = TRANS_SOFT_ABORT;
 408                 write(acceptfd, &control, sizeof(char));
 409                 printf("DEBUG -> Sending TRANS_SOFT_ABORT\n");
 410                 //send number of oids not found and the missing oids
 411                 write(acceptfd, &objnotfound, sizeof(int));
 412                 if(objnotfound != 0)
 413                         write(acceptfd, oidnotfound, (sizeof(unsigned int) * objnotfound));
 414         }
 415
 416         //Do the following when TRANS_DISAGREE is sent
 417         if(control == TRANS_DISAGREE) {
 418                 //Set the reference count of the object to 1 in mainstore for garbage collection
 419                 ptr = modptr;
 420                 for(i = 0; i< fixed->nummod; i++) {
 421                         headptr = (objheader_t *) ptr;
 422                         headptr->rcount = 1;
 423                         ptr += sizeof(objheader_t) + classsize[headptr->type];
 424                 }
 425                 //Unlock objects that was locked in the trans
 426                 for(i = 0; i< objlocked ; i++) {
 427                         mobj = mhashSearch(oidlocked[i]);// find the header address
 428                         ((objheader_t *)mobj)->status &= ~(LOCK);
 429                 }
 430         }
 431
 432         //Fill out the structure required for a trans commit process if pile receives a TRANS_COMMIT
 433         transinfo->objmod = oidmod;
 434         transinfo->objlocked = oidlocked;
 435         transinfo->objnotfound = oidnotfound;
 436         transinfo->modptr = modptr;
 437         transinfo->nummod = fixed->nummod;
 438         transinfo->numlocked = objlocked;
 439         transinfo->numnotfound = objnotfound;
 440
 441         return control;
 442 }
 443
 444 //Processes oids in the TRANS_COMMIT request at the participant end and sends an ack back
 445 int transCommitProcess(trans_commit_data_t *transinfo, int acceptfd) {
 446         objheader_t *header;
 447         int i = 0, offset = 0;
 448         char control;
 449         //Process each modified object saved in the mainobject store
 450         for(i=0; i<transinfo->nummod; i++) {
 451                 if((header = (objheader_t *) mhashSearch(transinfo->objmod[i])) == NULL) {
 452                         printf("mhashserach returns NULL\n");
 453                 }
 454                 //change reference count of older address and free space in objstr ??
 455                 header->rcount = 1; //Not sure what would be th val
 456                 //change ptr address in mhash table
 457                 mhashRemove(transinfo->objmod[i]);
 458                 mhashInsert(transinfo->objmod[i], (transinfo->modptr + offset));
 459                 offset += sizeof(objheader_t) + classsize[header->type];
 460                 //update object version
 461                 header = (objheader_t *) mhashSearch(transinfo->objmod[i]);
 462                 header->version += 1;
 463         }
 464         for(i=0; i<transinfo->numlocked; i++) {
 465                 //unlock objects
 466                 header = (objheader_t *) mhashSearch(transinfo->objlocked[i]);
 467                 header->status &= ~(LOCK);
 468         }
 469
 470         //TODO Update location lookup table
 471
 472         //send ack to coordinator
 473         control = TRANS_SUCESSFUL;
 474         if(send((int)acceptfd, &control, sizeof(char), 0) < 0) {
 475                 perror("Error sending ACK to coordinator\n");
 476         }
 477
 478         return 0;
 479 }
 480