Esempio n. 1
0
void* ReceiveStateFromParticipant(void* _rcv_thread_arg) {
    ReceiveStateThreadArgument *rcv_thread_arg = (ReceiveStateThreadArgument *)_rcv_thread_arg;
    int pid = rcv_thread_arg->pid;
    int tid = rcv_thread_arg->transaction_id;
    Process *p = rcv_thread_arg->p;
    char buf[kMaxDataSize];
    int num_bytes;
    //TODO: write code to extract multiple messages

    fd_set temp_set;
    FD_ZERO(&temp_set);
    FD_SET(p->get_fd(pid), &temp_set);
    int fd_max = p->get_fd(pid);
    int rv;
    rv = select(fd_max + 1, &temp_set, NULL, NULL, (timeval*)&kTimeout);
    if (rv == -1) { //error in select
        // cout << "P" << p->get_pid() << ": ERROR in select() for P" << pid << strerror(errno)<< endl;
        rcv_thread_arg->st = PROCESSTIMEOUT;
        p->RemoveFromUpSet(pid);
    } else if (rv == 0) {   //timeout
        rcv_thread_arg->st = PROCESSTIMEOUT;
        p->RemoveFromUpSet(pid);
    } else {    // activity happened on the socket
        if ((num_bytes = recv(p->get_fd(pid), buf, kMaxDataSize - 1, 0)) == -1) {
            // cout << "P" << p->get_pid() << ": ERROR in receiving for P" << pid << endl;
            rcv_thread_arg->st = PROCESSTIMEOUT;
            p->RemoveFromUpSet(pid);
        } else if (num_bytes == 0) {     //connection closed
            // cout << "P" << p->get_pid() << ": Connection closed by P" << pid << endl;
            // if participant closes connection, it is equivalent to it crashing
            // can treat it as TIMEOUT
            // TODO: verify argument
            rcv_thread_arg->st = PROCESSTIMEOUT;
            p->RemoveFromUpSet(pid);
            //TODO: handle connection close based on different cases
        } else {
            buf[num_bytes] = '\0';
            cout << "P" << p->get_pid() << ": STATE received from P" << pid << ": " << buf <<  endl;

            string extracted_msg;
            int received_tid;
            // in this case, we don't care about the received_tid,
            // because it will surely be for the transaction under consideration
            p->ExtractMsg(string(buf), extracted_msg, received_tid);

            ProcessState msg = static_cast<ProcessState>(atoi(extracted_msg.c_str()));
            rcv_thread_arg->st = msg;
            //assumes that correct message type is sent by participant

            // if (msg==)  {    // it's a YES
            //     received_msg_type = YES;
            // } else if (extracted_msg == msg2) { // it's a NO
            //     received_msg_type = NO;
            // } else {
            //     //TODO: take actions appropriately, like check log for previous transaction decision.
            //     cout << "P" << p->get_pid() << ": Unexpected msg received from P" << pid << endl;
            //     received_msg_type = ERROR;
            // }
        }
    }
    // cout << "P" << p->get_pid() << ": Receive thread exiting for P" << pid << endl;
    return NULL;
}
Esempio n. 2
0
// thread for receiving SR/DR messages from one process
void* ReceiveUp(void* _arg) {
    ReceiveSDRUpThreadArgument* arg = (ReceiveSDRUpThreadArgument*)_arg;
    Process* p = arg->p;
    int for_whom = arg->for_whom;

    char buf[kMaxDataSize];
    int num_bytes;
    pthread_t sr_response_thread;

    set<string> many_messages;

    ofstream outf("log/up/" + to_string(p->get_pid()) + "from" + to_string(for_whom));

    if (!outf.is_open())
        cout << "Failed to open log file for up" << endl;
    outf<<"All set to receive"<<endl;
    while (true) {
        // cout<<"in "<<p->get_pid()<<"; "<<for_whom<<" fd is "<<p->get_up_fd(for_whom)<<endl;
        if ((num_bytes = recv(p->get_up_fd(for_whom), buf, kMaxDataSize - 1, 0)) == -1)
        {
            // cout << "P" << p->get_pid() << ": ERROR in receiving UP for P" << for_whom << endl;
            // p->RemoveFromUpSet(for_whom);
        }
        else if (num_bytes == 0)
        {   //connection closed
            // cout << "P" << p->get_pid() << ": UP connection closed by P" << for_whom << endl;
            // p->RemoveFromUpSet(for_whom);
        }
        else
        {
            buf[num_bytes] = '\0';
            string bufstring(buf);
            vector<string> all_msgs = split(bufstring, '$');
            for (auto iter = all_msgs.begin(); iter != all_msgs.end(); iter++)
            {
                many_messages.insert(*iter);
            }
            string extracted_msg;
            int recvd_tid;

            for(auto iter = many_messages.begin(); iter!=many_messages.end(); iter++)
            {
                p->ExtractMsg(*iter, extracted_msg, recvd_tid);
                outf << "P" << p->get_pid() << ": UP recevd from P" << for_whom << ": " << *iter <<  endl;
                if (extracted_msg == kUpReq && recvd_tid == p->get_transaction_id())
                { 
                    //upreq sent only in total failure. means everyone is in same trans.
                    //if lower upreq got, ignore
                    p->SendMyUp(for_whom);
                }
                else 
                {//up set received
                    // outf<<"Up Set received "<<extracted_msg<<endl;
                    p->all_up_sets_[for_whom] = ConvertStringToSet(extracted_msg);
                    // outf<<"up set assigned "<< ConvertSetToString(p->all_up_sets_[for_whom])<<endl;
                }
            }

        }
        usleep(kGeneralSleep);
    }
}
Esempio n. 3
0
// thread for receiving ACK messages from ONE participant
void* ReceiveAckFromParticipant(void* _rcv_thread_arg) {
    ReceiveThreadArgument *rcv_thread_arg = (ReceiveThreadArgument *)_rcv_thread_arg;
    int pid = rcv_thread_arg->pid;
    int tid = rcv_thread_arg->transaction_id;
    string msg1 = rcv_thread_arg->expected_msg1;    //ACK
    string msg2 = rcv_thread_arg->expected_msg2;    //NULL
    Process *p = rcv_thread_arg->p;

    char buf[kMaxDataSize];
    int num_bytes;
    //TODO: write code to extract multiple messages

    fd_set temp_set;
    FD_ZERO(&temp_set);
    FD_SET(p->get_fd(pid), &temp_set);
    int fd_max = p->get_fd(pid);
    int rv;
    rv = select(fd_max + 1, &temp_set, NULL, NULL, (timeval*)&kTimeout);
    if (rv == -1) { //error in select
        // cout << "P" << p->get_pid() << ": ERROR in select() for P" << pid << strerror(errno)<< endl;
        rcv_thread_arg->received_msg_type = TIMEOUT;
        p->RemoveFromUpSet(pid);
    } else if (rv == 0) {   //timeout
        rcv_thread_arg->received_msg_type = TIMEOUT;
        p->RemoveFromUpSet(pid);
    } else {    // activity happened on the socket
        if ((num_bytes = recv(p->get_fd(pid), buf, kMaxDataSize - 1, 0)) == -1) {
            // cout << "P" << p->get_pid() << ": ERROR in receiving for P" << pid << endl;
            rcv_thread_arg->received_msg_type = TIMEOUT;
            p->RemoveFromUpSet(pid);
        } else if (num_bytes == 0) {     //connection closed
            // cout << "P" << p->get_pid() << ": Connection closed by P" << pid << endl;
            // if participant closes connection, it is equivalent to it crashing
            // can treat it as TIMEOUT
            // TODO: verify argument
            rcv_thread_arg->received_msg_type = TIMEOUT;
            p->RemoveFromUpSet(pid);
            //TODO: handle connection close based on different cases
        } else {
            buf[num_bytes] = '\0';
            cout << "P" << p->get_pid() << ": ACK received from P" << pid <<  endl;

            string extracted_msg;
            int received_tid;
            // in this case, we don't care about the received_tid,
            // because it will surely be for the transaction under consideration
            p->ExtractMsg(string(buf), extracted_msg, received_tid);

            if (extracted_msg == msg1) {    // it's an ACK
                rcv_thread_arg->received_msg_type = ACK;
            } else {
                //TODO: take actions appropriately, like check log for previous transaction decision.
                timeval timeofday;
                gettimeofday(&timeofday, NULL);
                cout << "P" << p->get_pid() << ": Expecting ack. Unexpected msg received from P" << pid << buf<< " at "<<timeofday.tv_sec<<"."<<timeofday.tv_usec<<endl;

                rcv_thread_arg->received_msg_type = ERROR;
            }
        }
    }
    // cout << "P" << p->get_pid() << ": Receive thread exiting for P" << pid << endl;
    return NULL;
}