src/server/Server.cxx

   1 /***************************************************************************
   2  *   Copyright (C) 2007 by www.databasecache.com                           *
   3  *   Contact: praba_tuty@databasecache.com                                 *
   4  *                                                                         *
   5  *   This program is free software; you can redistribute it and/or modify  *
   6  *   it under the terms of the GNU General Public License as published by  *
   7  *   the Free Software Foundation; either version 2 of the License, or     *
   8  *   (at your option) any later version.                                   *
   9  *                                                                         *
  10  *   This program is distributed in the hope that it will be useful,       *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
  15   ***************************************************************************/
  16 #include<CSql.h>
  17 #include<SessionImpl.h>
  18 #include<Debug.h>
  19 #include<Process.h>
  20 #include<Database.h>
  21 #include<Transaction.h>
  22 #include<Lock.h>
  23 #include<CacheTableLoader.h>
  24
  25 int srvStop =0;
  26 static void sigTermHandler(int sig)
  27 {
  28     printf("Received signal %d\nStopping the server\n", sig);
  29     srvStop = 1;
  30 }
  31
  32 bool checkDead(pid_t  pid)
  33 {
  34     int ret = os::kill(pid, 0);
  35     if (ret == -1) return true; else return false;
  36 }
  37
  38 DbRetVal releaseAllResources(Database *sysdb, ThreadInfo *info )
  39 {
  40     printf("Releasing all the resources for process %d %lu\n", info->pid_, info->thrid_);
  41     //recover for all the mutexes in has_
  42     for (int i =0;  i < MAX_MUTEX_PER_THREAD; i++)
  43     {
  44         if (info->has_[i] != NULL)
  45         {
  46             printf("Dead Procs: %d %lu holding mutex %x %s) \n", info->pid_, info->thrid_, info->has_[i], info->has_[i]->name);
  47             logFine(logger, "Dead Procs: %d %lu holding mutex %x %s) \n", info->pid_, info->thrid_, info->has_[i], info->has_[i]->name);
  48             //TODO::recovery of mutexes
  49             //info->has_[i]->recoverMutex();
  50             srvStop = 1;
  51         }
  52     }
  53     TransactionManager *tm = new TransactionManager();
  54     LockManager *lm = new LockManager(sysdb);
  55     for (int i = 0 ;i < MAX_THREADS_PER_PROCESS; i++)
  56     {
  57         if (info->thrTrans_[i].trans_ != NULL && info->thrTrans_[i].trans_->status_ == TransRunning)
  58         {
  59             printf("Rollback Transaction %x\n", info->thrTrans_[i].trans_);
  60             tm->rollback(lm, info->thrTrans_[i].trans_);
  61         }
  62     }
  63     info->init();
  64     delete tm;
  65     delete lm;
  66     return OK;
  67 }
  68
  69 DbRetVal cleanupDeadProcs(Database *sysdb)
  70 {
  71     DbRetVal rv = sysdb->getProcessTableMutex(false);
  72     if (OK != rv)
  73     {
  74         printError(rv,"Unable to get process table mutex");
  75         return rv;
  76     }
  77     pid_t pid;
  78     pid = os::getpid();
  79     pthread_t thrid = os::getthrid();
  80
  81
  82     ThreadInfo* pInfo = sysdb->getThreadInfo(0);
  83     int i=0;
  84     ThreadInfo* freeSlot = NULL;
  85     for (; i < Conf::config.getMaxProcs(); i++)
  86     {
  87         //check whether it is alive
  88         if (pInfo->pid_ !=0 && checkDead(pInfo->pid_)) releaseAllResources(sysdb, pInfo);
  89         pInfo++;
  90     }
  91     sysdb->releaseProcessTableMutex(false);
  92     return OK;
  93 }
  94
  95
  96 DbRetVal logActiveProcs(Database *sysdb)
  97 {
  98     DbRetVal rv = sysdb->getProcessTableMutex(false);
  99     if (OK != rv)
 100     {
 101         printError(rv,"Unable to get process table mutex");
 102         return rv;
 103     }
 104     ThreadInfo* pInfo = sysdb->getThreadInfo(0);
 105     int i=0;
 106     ThreadInfo* freeSlot = NULL;
 107     for (; i < Conf::config.getMaxProcs(); i++)
 108     {
 109         if (pInfo->pid_ !=0 )  logFine(logger, "Registered Procs: %d %lu\n", pInfo->pid_, pInfo->thrid_);
 110         pInfo++;
 111     }
 112     sysdb->releaseProcessTableMutex(false);
 113     return OK;
 114 }
 115
 116
 117
 118 int main()
 119 {
 120     SessionImpl session;
 121     DbRetVal rv = session.readConfigFile();
 122     if (rv != OK)
 123     {
 124         printf("Unable to read the configuration file \n");
 125         return 1;
 126     }
 127     os::signal(SIGINT, sigTermHandler);
 128     os::signal(SIGTERM, sigTermHandler);
 129     rv = logger.startLogger(Conf::config.getLogFile(), true);
 130     if (rv != OK)
 131     {
 132         printf("Unable to start the logger\n");
 133         return 2;
 134     }
 135
 136     logFine(logger, "Server Started");
 137     int ret  = session.initSystemDatabase();
 138     if (0  != ret)
 139     {
 140         printf(" System Database Initialization failed\n");
 141         return 3;
 142     }
 143     printf("System Database initialized\n");
 144
 145
 146     bool end = false;
 147
 148     struct timeval timeout, tval;
 149     timeout.tv_sec = 5;
 150     timeout.tv_usec = 0;
 151     Database* sysdb = session.getSystemDatabase();
 152     printf("Database server recovering cached tables...\n");
 153
 154     system("cachetable -u root -p manager -r");
 155
 156     printf("Cached Tables recovered\n");
 157
 158     printf("Database server started\n");
 159
 160     while(!srvStop)
 161     {
 162         tval.tv_sec = timeout.tv_sec;
 163         tval.tv_usec = timeout.tv_usec;
 164         os::select(0, 0, 0, 0, &tval);
 165
 166         //send signal to all the registered process..check they are alive
 167         cleanupDeadProcs(sysdb);
 168
 169     }
 170
 171     logFine(logger, "Server Exiting");
 172     logActiveProcs(sysdb);
 173     printf("Server Exiting\n");
 174     logFine(logger, "Server Ended");
 175     logger.stopLogger();
 176     session.destroySystemDatabase();
 177     return 0;
 178 }