#include <pthread.h>
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
/* implementa il grafo di esempio1 con i mutex
 */
pthread_mutex_t m=PTHREAD_MUTEX_INITIALIZER;
pthread_mutex_t m1=PTHREAD_MUTEX_INITIALIZER;
pthread_mutex_t m2=PTHREAD_MUTEX_INITIALIZER;
pthread_mutex_t m3=PTHREAD_MUTEX_INITIALIZER;
pthread_mutex_t m4=PTHREAD_MUTEX_INITIALIZER;
pthread_mutex_t m5=PTHREAD_MUTEX_INITIALIZER;
pthread_mutex_t m6=PTHREAD_MUTEX_INITIALIZER;
pthread_mutex_t m7=PTHREAD_MUTEX_INITIALIZER;

void *thread_function1(void *arg) {
  int i;

  for(i=0;i<5;i++){
    printf("Sono il thread1!\n");
    sleep(1);
  }
  pthread_mutex_unlock(&m);
  pthread_mutex_unlock(&m1);
  pthread_mutex_unlock(&m2);
  return NULL;
}

void *thread_function2(void *arg) {
  int i;

  pthread_mutex_lock(&m);
  for(i=0;i<5;i++){
    printf("\t Sono il thread2!\n");
    sleep(1);
  }
  pthread_mutex_unlock(&m3);

  return NULL;
}

void *thread_function3(void *arg) {
  int i;

  pthread_mutex_lock(&m1);
  for(i=0;i<5;i++){
    printf("\t\t Sono il thread3!\n");
    sleep(1);
  }
  pthread_mutex_unlock(&m4);
  return NULL;
}

void *thread_function4(void *arg) {
  int i;

  pthread_mutex_lock(&m2);
  for(i=0;i<10;i++){
    printf("\t\t\t\t Sono il thread4!\n");
    sleep(1);
  }
  pthread_mutex_unlock(&m5);   
  return NULL;
}

void *thread_function5(void *arg) {
  int i;

    pthread_mutex_lock(&m3);
    pthread_mutex_lock(&m4);
    printf("\t\t\t\t\t Sono il thread5!\n");
    sleep(1);
    pthread_mutex_unlock(&m6);   
  return NULL;
}

void *thread_function6(void *arg) {
  int i;

    pthread_mutex_lock(&m5);
    pthread_mutex_lock(&m6);
    printf("Sono il thread6!\n");
    sleep(1);
  return NULL;
}



int main(void) {

  pthread_t mythread1, mythread2, mythread3, mythread4, mythread5, mythread6;

  pthread_mutex_lock(&m);
  pthread_mutex_lock(&m1);
  pthread_mutex_lock(&m2);
  pthread_mutex_lock(&m3);
  pthread_mutex_lock(&m4);
  pthread_mutex_lock(&m5);
  pthread_mutex_lock(&m6);

  if ( pthread_create( &mythread1, NULL, thread_function1, NULL) ) {
    printf("errore di creazione thread.");
    abort();
  }

  if ( pthread_create( &mythread2, NULL, thread_function2, NULL) ) {
    printf("errore di creazione thread.");
    abort();
  }

  if ( pthread_create( &mythread3, NULL, thread_function3, NULL) ) {
    printf("errore di creazione thread.");
    abort();
  }

  if ( pthread_create( &mythread4, NULL, thread_function4, NULL) ) {
    printf("errore di creazione thread.");
    abort();
  }

  if ( pthread_create( &mythread5, NULL, thread_function5, NULL) ) {
    printf("errore di creazione thread.");
    abort();
  }

  if ( pthread_create( &mythread6, NULL, thread_function6, NULL) ) {
    printf("errore di creazione thread.");
    abort();
  }
   pthread_join(mythread1, NULL);
   pthread_join(mythread2, NULL);
   pthread_join(mythread3, NULL);
   pthread_join(mythread4, NULL);
   pthread_join(mythread5, NULL);
   pthread_join(mythread6, NULL);



 
  exit(0);

}