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Ahoj potřeboval bych od Vás opět poradit, problém se týká synchronizace. Svůj program jsem aplikoval na problematiku 5 filozofů, ale mám pocit, že dochází k deathlock a starvation. Předem Vám děkuji, za odpovědi.

#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <unistd.h>
#include <time.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/shm.h>
#include <sys/sem.h>
#include <sys/ipc.h>

#include "semun.h"

#define N 5
#define LEFT ((philosopherNumb - 1 + N) % N)
#define RIGHT ((philosopherNumb + 1) % N)
#define LOCK (N+1)

int setSemValue(void);
int delSemaphore(void);
int waitTime(void);
int think(void);
int eat(void);
int zpracujParametr(char *arg, int pocetArg);
int downSemaphore(int philosopherNumb);
int upSemaphore(int philosopherNumb);
int philosopher(int philosopherNumb);
void takeForks(int philosopherNumb);
void putForks(int philosopherNumb);
void testPhilosopher(int philosopherNumb);


enum STATE {thinking, hungry, eating};
char *state;

int semId;
int shmId;

//struct semData
//{
// int semId;
//} SEM_DATA;

struct shmData
{
 int count;
} SHM_DATA;

int main(int argc, char *argv[])
{
 struct shmData *sharedData;

 pid_t pid;
 pid_t children[N];
 
 
 int i = 0;
 int retCode = 0;
 //int shmId = 0;
 int stepsNumber = 0;
 void *sharedMemory = (void *) 0;
 // Overovani parametru
 if ((stepsNumber = zpracujParametr(argv[1], argc)) == -1)
 {
 fprintf(stderr, "Failed...\n");
 exit(EXIT_FAILURE);
 }
 // Inicializace sdilene pameti
 if ((shmId = shmget(IPC_PRIVATE, N + 1, 0666 | IPC_CREAT)) == -1)
 {
 fprintf(stderr, "Failed...\n");
 exit(EXIT_FAILURE);
 }
 // Zpristupneni sdilene pameti programu
 if ((sharedMemory = shmat(shmId, (void *) 0, 0)) == (void*) -1)
 {
 fprintf(stderr, "Failed...\n");
 exit(EXIT_FAILURE);
 }
 // Inicializace citace akci
 sharedData = (struct shmData *) sharedMemory;
 sharedData->count=0;
 // Odpojeni sdilene pameti
 if (shmdt(sharedMemory) == -1)
 {
 fprintf(stderr, "Failed...\n");
 exit(EXIT_FAILURE);
 }
 // Inicializace semaforu
 if ((semId = semget(IPC_PRIVATE, N + 1, 0666 | IPC_CREAT)) == -1)
 {
 fprintf(stderr, "Failed...\n");
 exit(EXIT_FAILURE);
 }
 // Zpristupneni semaforu
 setSemValue();
 // Zpristupneni sdilene pameti programu
 if ((state = shmat(shmId, (void *) 0, 0)) == (void*) -1)
 {
 fprintf(stderr, "Failed...\n");
 exit(EXIT_FAILURE);
 }
 // Vytvoreni podprocesu
 for (; i < N; i++)
 {
 pid = fork();
 switch (pid)
 {
 case -1:
 fprintf(stderr, "Failed...\n");
 exit(EXIT_FAILURE);
 break;
 case 0:
 while (stepsNumber != 0)
 {
 setbuf(stdout,NULL);
 philosopher(i);
 stepsNumber--;
 }
 exit(EXIT_SUCCESS);
 break;
 default:
 children[i] = pid;
 break;
 }
 }
 // Ukonceni potomknu;
 for (i = 0; i < N; i++)
 {
 retCode = waitpid(children[i], NULL, 0);
 if (retCode < 0)
 {
 retCode = kill(children[i], SIGTERM);
 if (retCode == -1)
 {
 fprintf(stderr, "Failed...\n");
 exit(EXIT_FAILURE);
 }
 }
 }
 // Odpojeni sdilene pameti
 if (shmdt(state) == -1)
 {
 fprintf(stderr, "Failed...\n");
 exit(EXIT_FAILURE);
 }
 // Uvolneni sdilene pameti
 if (shmctl(shmId, IPC_RMID, 0) == -1)
 {
 fprintf(stderr, "Failed...\n");
 exit(EXIT_FAILURE);
 }
 // Uvolneni semaforu
 if (delSemaphore() == -1)
 {
 fprintf(stderr, "Failed...\n");
 exit(EXIT_FAILURE);
 }
 exit(EXIT_SUCCESS);
}

int zpracujParametr(char *arg, int pocetArg)
{
 char *chyba;
 int errCode = 0;
 int cislo = 0;
 errno = 0;
 // V parametru je obsazen nepripustny pocet parametru nebo neni obsazen zadny parametr.
 if ((pocetArg > 2) || (pocetArg == 1))
 {
 return -1;
 }
 cislo = strtol(arg, &chyba, 10);
 errCode = errno;
 // Parametr obsahuje nepripustne hodnoty.
 if (errCode != 0)
 {
 return -1;
 }
 // Parametr obsahuje neciselne znaky.
 if (*chyba != '\0')
 {
 return -1;
 }
 // Parametr obsahuje zapornou hodnotu.
 if (cislo < 0)
 {
 return -1;
 }
 return cislo;
}

int waitTime(void)
{
 int pauseTime = 0;
 int retCode = 0;
 int errCode = 0;
 // Generovani nahodneho cisla v rozmezi O-100.
 srand((unsigned int) time(NULL) + (unsigned int) getpid());
 pauseTime = rand() % 101;
 retCode = usleep(pauseTime);
 errCode = errno;
 // Chybne skonceni funkce.
 if (retCode != 0)
 {
 return -1;
 }
 // Chybne skonceni funkce.
 if (errCode != 0)
 {
 return -1;
 }
 return 0;
}

int think(void)
{
 waitTime();
 return 0;
}

int eat(void)
{
 waitTime();
 return 2;
}

int setSemValue(void)
{
 union semun semUnion;

 semUnion.val = 0;
 int i = 0;
 for (; i < N + 1; i++)
 {
 if (semctl(semId, i, SETVAL, semUnion) == -1)
 {
 return -1;
 }
 }
 return 0;
}

int delSemaphore(void)
{
 union semun semUnion;

 if (semctl(semId, 0, IPC_RMID, semUnion) == -1)
 {
 return -1;
 }
 return 0;
}

int downSemaphore(int philosopherNumb)
{
 struct sembuf sem;

 sem.sem_num = philosopherNumb;
 sem.sem_op = -1;
 sem.sem_flg = 0;
 if (semop(semId, &sem, 1) == -1)
 {
 return -1;
 }
 return 0;
}

int upSemaphore(int philosopherNumb)
{
 struct sembuf sem;

 sem.sem_num = philosopherNumb;
 sem.sem_op = 1;
 sem.sem_flg = 0;
 if (semop(semId, &sem, 1) == -1)
 {
 return -1;
 }
 return 0;
}

void takeForks(int philosopherNumb)
{
 downSemaphore(LOCK);
 state[philosopherNumb] = hungry;
 testPhilosopher(philosopherNumb);
 upSemaphore(LOCK);
 downSemaphore(philosopherNumb);
}

void putForks(int philosopherNumb)
{
 downSemaphore(LOCK);
 state[philosopherNumb] = thinking;
 testPhilosopher(LEFT);
 testPhilosopher(RIGHT);
 upSemaphore(LOCK);
}

void testPhilosopher(int philosopherNumb)
{
 if (state[philosopherNumb] == hungry && state[LEFT] != eating && state[RIGHT] != eating)
 {
 state[philosopherNumb] = eating;
 upSemaphore(philosopherNumb);
 }
}

int philosopher(int philosopherNumb)
{
 state[philosopherNumb] = thinking;
 printf("F(%d) Mysli\n", philosopherNumb);
 think();
 printf("F(%d) Bere vidlicky\n", philosopherNumb);
 takeForks(philosopherNumb);
 printf("F(%d) Ji\n", philosopherNumb);
 eat();
 printf("F(%d) Poklada vidlicky\n", philosopherNumb);
 putForks(philosopherNumb);
 return 0;
}
-------------------------semun.h------------------------------------------------------------
#if defined(__GNU_LIBRARY__) && !defined(_SEM_SEMUN_UNDEFINED)
#else
 union semun 
 {
 int val;                    
 struct semid_ds *buf;       
 unsigned short int *array; 
 struct seminfo *__buf;      
 };
#endif