11 #define LISTEN_PORT 2156
12 #define BACKLOG 10 //max pending connections
13 #define RECEIVE_BUFFER_SIZE 2048
15 extern int classsize[];
17 objstr_t *mainobjstore;
21 //Initialize main object store
22 mainobjstore = objstrCreate(DEFAULT_OBJ_STORE_SIZE);
23 if (mhashCreate(HASH_SIZE, LOADFACTOR))
26 if (lhashCreate(HASH_SIZE, LOADFACTOR))
29 //pthread_t threadListen;
30 //pthread_create(&threadListen, NULL, dstmListen, NULL);
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;
44 listenfd = socket(AF_INET, SOCK_STREAM, 0);
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);
56 if (bind(listenfd, (struct sockaddr *)&my_addr, addrlength) == -1)
62 if (listen(listenfd, BACKLOG) == -1)
68 printf("Listening on port %d, fd = %d\n", LISTEN_PORT, listenfd);
71 acceptfd = accept(listenfd, (struct sockaddr *)&client_addr, &addrlength);
72 pthread_create(&thread_dstm_accept, NULL, dstmAccept, (void *)acceptfd);
77 void *dstmAccept(void *acceptfd)
79 int numbytes,i, val, retval;
81 char buffer[RECEIVE_BUFFER_SIZE], control,ctrl;
85 trans_commit_data_t transinfo;
87 int fd_flags = fcntl((int)acceptfd, F_GETFD), size;
89 printf("Recieved connection: fd = %d\n", (int)acceptfd);
90 if((retval = recv((int)acceptfd, &control, sizeof(char), 0)) <= 0) {
91 perror("Error in receiving control from coordinator\n");
96 printf("DEBUG -> Recv READ_REQUEST from Coordinator\n");
97 if((retval = recv((int)acceptfd, &oid, sizeof(unsigned int), 0)) <= 0) {
98 perror("Error receiving object from cooridnator\n");
101 srcObj = mhashSearch(oid);
102 h = (objheader_t *) srcObj;
103 size = sizeof(objheader_t) + sizeof(classsize[h->type]);
105 ctrl = OBJECT_NOT_FOUND;
106 if(send((int)acceptfd, &ctrl, sizeof(char), 0) < 0) {
107 perror("Error sending control msg to coordinator\n");
110 //char responsemessage[sizeof(char)+sizeof(int)];
113 if(send((int)acceptfd, &ctrl, sizeof(char), 0) < 0) {
114 perror("Error sending control msg to coordinator\n");
117 //responsemessage[0]=OBJECT_FOUND;
119 //*((int *)(&responsemessage[1])) = sizeof(objheader_t) + classsize[h->type];
120 //if(send((int)acceptfd, &responsemessage, sizeof(responsemessage), 0) < 0) {
121 // perror("Error sending control msg to coordinator\n");
125 if(send((int)acceptfd, &size, sizeof(int), 0) < 0) {
126 perror("Error sending size of object to coordinator\n");
128 if(send((int)acceptfd, h, size, 0) < 0) {
129 perror("Error in sending object\n");
134 case READ_MULT_REQUEST:
135 printf("DEBUG-> READ_MULT_REQUEST\n");
139 printf("DEBUG -> MOVE_REQUEST\n");
142 case MOVE_MULT_REQUEST:
143 printf("DEBUG -> MOVE_MULT_REQUEST\n");
147 printf("DEBUG -> Recv TRANS_REQUEST from Coordinator\n");
148 if((val = readClientReq((int)acceptfd, &transinfo)) != 0) {
149 printf("Error in readClientReq\n");
154 printf("DEBUG -> dstmAccept: Error Unknown opcode %d\n", control);
156 if (close((int)acceptfd) == -1)
161 printf("Closed connection: fd = %d\n", (int)acceptfd);
164 free(transinfo.objmod);
165 free(transinfo.objlocked);
166 free(transinfo.objnotfound);
170 int readClientReq(int acceptfd, trans_commit_data_t *transinfo) {
171 char *ptr, control, prevctrl, sendctrl, newctrl;
172 void *modptr, *header;
173 objheader_t *tmp_header;
175 int sum = 0, i, N, n, val, retval;
177 //Reads to process the TRANS_REQUEST protocol further
179 N = sizeof(fixed) - 1;
180 ptr = (char *)&fixed;;
181 fixed.control = TRANS_REQUEST;
183 n = recv((int)acceptfd, (void *) ptr+1+sum, N-sum, 0);
184 // printf("DEBUG -> 1. Reading %d bytes \n", n);
186 } while(sum < N && n != 0);
188 //printf("Machine count = %d\tnumread = %d\tnummod = %d\tsum_bytes = %d\n", fixed.mcount, fixed.numread, fixed.nummod, fixed.sum_bytes);
190 int mcount = fixed.mcount;
191 N = mcount * sizeof(unsigned int);
192 unsigned int listmid[mcount];
193 ptr = (char *) listmid;
196 n = recv((int)acceptfd, (void *) ptr+sum, N-sum, 0);
197 // printf("DEBUG -> 2. Reading %d bytes cap = %d\n", n, N);
199 } while(sum < N && n != 0);
201 // Read oid and version tuples
202 int numread = fixed.numread;
203 N = numread * (sizeof(unsigned int) + sizeof(short));
205 if(numread != 0) { // If pile contains objects to be read
206 // N = numread * (sizeof(unsigned int) + sizeof(short));
210 n = recv((int)acceptfd, (void *) objread, N, 0);
211 // printf("DEBUG -> 3. Reading %d bytes cap = %d\n", n, N);
213 } while(sum < N && n != 0);
214 // printf("DEBUG -> Recv objs from Coordinator %d %d %d %d\n", *objread, *(objread + 6), *(objread + 12), *(objread + 18));
217 // Read modified objects
218 if(fixed.nummod != 0) { // If pile contains modified objects
219 if ((modptr = objstrAlloc(mainobjstore, fixed.sum_bytes)) == NULL) {
220 printf("objstrAlloc error for modified objects %s, %d", __FILE__, __LINE__);
224 do { // Recv the objs that are modified at Coordinator
225 n = recv((int)acceptfd, modptr+sum, fixed.sum_bytes-sum, 0);
226 // printf("DEBUG -> 4. Reading %d bytes cap = %d, oid = %d\n", n, fixed.sum_bytes, *((int *)modptr));
228 } while (sum < fixed.sum_bytes && n != 0);
231 //Send control message as per all votes from all oids in the machine
232 if((prevctrl = handleTransReq(acceptfd, &fixed, transinfo, listmid, objread, modptr)) == 0 ) {
233 printf("Handle req error\n");
236 //Read for new control message from Coordiator
237 if((retval = recv((int)acceptfd, &control, sizeof(char), 0)) <= 0 ) {
238 perror("Error in receiving control message");
244 printf("DEBUG -> Recv TRANS_ABORT from Coordinator\n");
245 //send ack to coordinator
246 sendctrl = TRANS_SUCESSFUL;
247 if(send((int)acceptfd, &sendctrl, sizeof(char), 0) < 0) {
248 perror("Error sending ACK to coordinator\n");
251 //Mark all ref counts as 1 and do garbage collection
253 for(i = 0; i< fixed.nummod; i++) {
254 tmp_header = (objheader_t *)ptr;
255 tmp_header->rcount = 1;
256 ptr += sizeof(objheader_t) + classsize[tmp_header->type];
258 //Unlock objects that was locked in this machine due to this transaction
259 for(i = 0; i< transinfo->numlocked; i++) {
260 header = mhashSearch(transinfo->objlocked[i]);// find the header address
261 ((objheader_t *)header)->status &= ~(LOCK);
267 printf("DEBUG -> Recv TRANS_COMMIT from Coordinator\n");
268 if((val = transCommitProcess(transinfo, (int)acceptfd)) != 0) {
269 printf("Error in transCommitProcess %s, %d\n", __FILE__, __LINE__);
272 case TRANS_ABORT_BUT_RETRY_COMMIT:
273 printf("DEBUG -> Recv TRANS_ABORT_BUT_RETRY_COMMIT from Coordinator\n");
274 //Process again after waiting for sometime and on prev control message sent
277 sendctrl = TRANS_AGREE;
278 if(send((int)acceptfd, &sendctrl, sizeof(char), 0) < 0) {
279 perror("Error sending ACK to coordinator\n");
283 case TRANS_SOFT_ABORT:
284 if((newctrl = handleTransReq(acceptfd, &fixed, transinfo, listmid, objread, modptr)) == 0 ) {
285 printf("Handle req error\n");
287 if(newctrl == prevctrl){
289 newctrl = TRANS_DISAGREE;
290 if(send((int)acceptfd, &newctrl, sizeof(char), 0) < 0) {
291 perror("Error sending ACK to coordinator\n");
293 //Set the reference count of the object to 1 in mainstore for garbage collection
295 for(i = 0; i< fixed.nummod; i++) {
296 tmp_header = (objheader_t *) ptr;
297 tmp_header->rcount = 1;
298 ptr += sizeof(objheader_t) + classsize[tmp_header->type];
300 //Unlock objects that was locked in this machine due to this transaction
301 for(i = 0; i< transinfo->numlocked; i++) {
302 ptr = mhashSearch(transinfo->objlocked[i]);// find the header address
303 ((objheader_t *)ptr)->status &= ~(LOCK);
307 //Send new control message
308 if(send((int)acceptfd, &newctrl, sizeof(char), 0) < 0) {
309 perror("Error sending ACK to coordinator\n");
317 case TRANS_ABORT_BUT_RETRY_COMMIT_WITH_RELOCATING:
318 //TODO expect another transrequest from client
319 printf("DEBUG -> Recv TRANS_ABORT_BUT_RETRY_COMMIT_WITH_RELOCATING from Coordinator\n");
322 printf("No response to TRANS_AGREE OR DISAGREE protocol\n");
323 //TODO Use fixed.trans_id TID since Client may have died
330 //This function runs a decision after all objects are weighed under one of the 4 possibilities
331 //and returns the appropriate control message to the Ccordinator
332 char handleTransReq(int acceptfd, fixed_data_t *fixed, trans_commit_data_t *transinfo, unsigned int *listmid, char *objread, void *modptr) {
335 char control = 0, ctrlmissoid, *ptr;
338 unsigned int *oidnotfound, *oidlocked, *oidmod;
340 oidnotfound = (unsigned int *) calloc(fixed->numread + fixed->nummod, sizeof(unsigned int));
341 oidlocked = (unsigned int *) calloc(fixed->numread + fixed->nummod, sizeof(unsigned int));
342 oidmod = (unsigned int *) calloc(fixed->nummod, sizeof(unsigned int));
344 // Counters and arrays to formulate decision on control message to be sent
345 int objnotfound = 0, objlocked = 0, objmod =0, v_nomatch = 0, v_matchlock = 0, v_matchnolock = 0;
346 int objmodnotfound = 0, nummodfound = 0;
348 objheader_t *headptr;
350 //Process each object present in the pile
352 //printf("DEBUG -> Total objs involved in trans is %d\n",fixed->nummod + fixed->numread);
354 //Process each oid in the machine pile/ group
355 for (i = 0; i < fixed->numread + fixed->nummod; i++) {
356 if (i < fixed->numread) {//Object is read
357 int incr = sizeof(unsigned int) + sizeof(short);// Offset that points to next position in the objread array
359 oid = *((unsigned int *)(objread + incr));
360 incr += sizeof(unsigned int);
361 version = *((short *)(objread + incr));
362 } else {//Obj is modified
363 headptr = (objheader_t *) ptr;
365 oidmod[objmod] = oid;//Array containing modified oids
367 version = headptr->version;
368 ptr += sizeof(objheader_t) + classsize[headptr->type];
370 //Check if object is still present in the machine since the beginning of TRANS_REQUEST
371 if ((mobj = mhashSearch(oid)) == NULL) {// Obj not found
372 //Save the oids not found for later use
373 oidnotfound[objnotfound] = ((objheader_t *)mobj)->oid;
375 } else { // If obj found in machine (i.e. has not moved)
376 //Check if obj is locked
377 if ((((objheader_t *)mobj)->status & LOCK) == LOCK) {
378 if (version == ((objheader_t *)mobj)->version) { // If version match
380 } else {//If versions don't match ..HARD ABORT
382 //send TRANS_DISAGREE to Coordinator
383 control = TRANS_DISAGREE;
384 if((val = write(acceptfd, &control, sizeof(char))) <= 0) {
385 perror("Error in sending control to the Coordinator\n");
388 printf("DEBUG -> Sending TRANS_DISAGREE\n");
391 } else {//Obj is not locked , so lock object
392 ((objheader_t *)mobj)->status |= LOCK;
393 //Save all object oids that are locked on this machine during this transaction request call
394 oidlocked[objlocked] = ((objheader_t *)mobj)->oid;
396 if (version == ((objheader_t *)mobj)->version) { //If versions match
398 } else { //If versions don't match
400 //send TRANS_DISAGREE to Coordinator
401 control = TRANS_DISAGREE;
402 if((val = write(acceptfd, &control, sizeof(char))) <= 0) {
403 perror("Error in sending control to the Coordinator\n");
406 printf("DEBUG -> Sending TRANS_DISAGREE\n");
413 //printf("No of objs locked = %d\n", objlocked);
414 //printf("No of v_nomatch = %d\n", v_nomatch);
415 //printf("No of objs v_match but are did not have locks before = %d\n", v_matchnolock);
416 //printf("No of objs v_match but had locks before = %d\n", v_matchlock);
417 //printf("No of objs not found = %d\n", objnotfound);
418 //printf("No of objs modified but not found = %d\n", objmodnotfound);
420 //Decide what control message(s) to send
421 if(v_matchnolock == fixed->numread + fixed->nummod) {
422 //send TRANS_AGREE to Coordinator
423 control = TRANS_AGREE;
424 if((val = write(acceptfd, &control, sizeof(char))) <= 0) {
425 perror("Error in sending control to Coordinator\n");
428 printf("DEBUG -> Sending TRANS_AGREE\n");
431 if((v_matchlock > 0 && v_nomatch == 0) || (objnotfound > 0 && v_nomatch == 0)) {
432 //send TRANS_SOFT_ABORT to Coordinator
433 control = TRANS_SOFT_ABORT;
434 if((val = write(acceptfd, &control, sizeof(char))) <=0 ) {
435 perror("Error in sending control back to coordinator\n");
438 printf("DEBUG -> Sending TRANS_SOFT_ABORT\n");
439 //send number of oids not found and the missing oids
440 if((val = write(acceptfd, &objnotfound, sizeof(int))) <= 0) {
441 perror("Error in sending no of objects that are not found\n");
444 if(objnotfound != 0) {
445 if((val = write(acceptfd, oidnotfound, (sizeof(unsigned int) * objnotfound))) <= 0) {
446 perror("Error in sending objects that are not found\n");
452 //Do the following when TRANS_DISAGREE is sent
453 if(control == TRANS_DISAGREE) {
454 //Set the reference count of the object to 1 in mainstore for garbage collection
456 for(i = 0; i< fixed->nummod; i++) {
457 headptr = (objheader_t *) ptr;
459 ptr += sizeof(objheader_t) + classsize[headptr->type];
461 //Unlock objects that was locked in the trans
462 for(i = 0; i< objlocked ; i++) {
463 mobj = mhashSearch(oidlocked[i]);// find the header address
464 ((objheader_t *)mobj)->status &= ~(LOCK);
468 //Fill out the structure required for a trans commit process if pile receives a TRANS_COMMIT
469 transinfo->objmod = oidmod;
470 transinfo->objlocked = oidlocked;
471 transinfo->objnotfound = oidnotfound;
472 transinfo->modptr = modptr;
473 transinfo->nummod = fixed->nummod;
474 transinfo->numlocked = objlocked;
475 transinfo->numnotfound = objnotfound;
480 //Processes oids in the TRANS_COMMIT request at the participant end and sends an ack back
481 int transCommitProcess(trans_commit_data_t *transinfo, int acceptfd) {
483 int i = 0, offset = 0;
485 //Process each modified object saved in the mainobject store
486 for(i=0; i<transinfo->nummod; i++) {
487 if((header = (objheader_t *) mhashSearch(transinfo->objmod[i])) == NULL) {
488 printf("mhashserach returns NULL\n");
490 //change reference count of older address and free space in objstr ??
491 header->rcount = 1; //Not sure what would be th val
492 //change ptr address in mhash table
493 mhashRemove(transinfo->objmod[i]);
494 mhashInsert(transinfo->objmod[i], (transinfo->modptr + offset));
495 offset += sizeof(objheader_t) + classsize[header->type];
496 //update object version
497 header = (objheader_t *) mhashSearch(transinfo->objmod[i]);
498 header->version += 1;
500 for(i=0; i<transinfo->numlocked; i++) {
502 header = (objheader_t *) mhashSearch(transinfo->objlocked[i]);
503 header->status &= ~(LOCK);
506 //TODO Update location lookup table
508 //send ack to coordinator
509 control = TRANS_SUCESSFUL;
510 if(send((int)acceptfd, &control, sizeof(char), 0) < 0) {
511 perror("Error sending ACK to coordinator\n");