locktable.h

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#ifndef LOCKTABLE_H
#define LOCKTABLE_H

#include <string>
#include "coartypes.h"

#define POSIX_SEM
#undef  SYSV_SEM 

#define NUM_ENTITIES 1000
#define LOCK_WAIT_TIME_UNRESTRICTED 0
#define LOCK_WAIT_TIME_NOWAIT 2
#define LOCK_WAIT_TIME_60S 1

typedef struct
{
    entity_id_t id;
    pid_t pid;  
} lockEntry;


// Riziko pri locktable je v tom ze aj po uvolneni zostavaju semafory a shared memory v systeme co moze sposobit ze casom bude ich 
// nedostatok. Mozno bude treba riesit synchronizaciu inak napr. pomocou mutexov z pthread


#ifdef DEBUG
class DLL_PUBLIC locktable
#else
class locktable
#endif
{

public:
  

    locktable(coar* _coarInstance,std::string fName,const char key,int numEntities=NUM_ENTITIES);
    
    ~locktable();
     

    int lockEntity(entity_id_t id);
    

    int unlockEntity(entity_id_t id,bool wait=false);
    
    

    void setLockWaitTime(int value);
    

    int getLockWaitTime();
    
    
    bool haveLock(entity_id_t id);
    
    
    void dumpLocktable();
    
private: 
    
    int openSHM();
    int openSemaphore();
    



    int writeEntityLockToSHM(entity_id_t id,bool clear=false);

    

    int lockSHM();
    int unlockSHM();
    int _lockEntity(entity_id_t id);
    int _unlockEntity(entity_id_t id);
    bool isEntityLocked(entity_id_t id);
    int clearEntityLockIfNotOwned(entity_id_t id);
    
    
#ifdef SYSV_SEM     
    int key;
    int semSetHandle;
#endif
#ifdef POSIX_SEM
    sem_t* mutex;
#endif    

    std::string name;
    std::string semName;
    int numEntities;
    key_t k;
    int shmHandle;
    void* shmPtr;
    int waitTime;
    int haveSHMLock;
    entity_id_t lockedEntityID;
    coar* coarInstance;
    
    
    char filler[100];
    
    
};

#endif // LOCKTABLE_H