BUT2/SCR/controle/devoir39/cntr_r3.05/Ex3/pizza.c

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2023-10-23 13:23:36 +02:00
#include <sys/types.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
/*
//ce bloc de code vient d'un exercice de tp que j'ai recuperer
int set_signal_handler(int signo, void (*handler)(int)) {
struct sigaction sa;
sa.sa_handler = handler; // call `handler` on signal
sigemptyset(&sa.sa_mask); // don't block other signals in handler
sa.sa_flags = SA_RESTART; // restart system calls
return sigaction(signo, &sa, NULL);
}
void sig_hand(int sig) {
}*/
void commander_une_pizza(int* p){
int i;
printf("pizza ordered!\n");
for (i=1; i<=8; i++){
write(p[1],&i,sizeof(int));
}
printf("pizza delivered!\n");
//kill(getppid(), SIGUSR1);
}
void prendre_une_part_de_pizza(int numEtudiant, int* p){
int numPartPizza;
read(p[0],&numPartPizza,sizeof(int));
printf("student %d takes piece %d\n",numEtudiant, numPartPizza);
//rendre atomique cette partie (mais je n'y arrive pas)
if (numPartPizza == 8){
commander_une_pizza(p);
}
else{
//kill(getppid(), SIGUSR1);
}
}
void reviser_et_manger_la_part_de_pizza(void){
sleep(3);
}
int main(int argc, char ** argv){
int Nbetudiant;
int i;
int pid;
int p[2];
if (argc != 2) {
printf("Usage: %s <NbEtudiants>\n",argv[0]);
exit(1);
}
Nbetudiant = strtol(argv[1],NULL,0);
//set_signal_handler(SIGUSR1,sig_hand);
pipe(p);
commander_une_pizza(p);
for (i=0; i<Nbetudiant; i++){
pid = fork();
if (pid == 0){
while (1){
prendre_une_part_de_pizza(i, p);
reviser_et_manger_la_part_de_pizza();
}
}
}
while (1){
// le professeur dort pendant que les eleves revises
sleep(1);
}
}