int main () {
int semaphore_id;
int segment_id;
char* shared_memory;
struct shmid_ds shmbuffer;
int segment_size, i, j;
pid_t child_pid;
segment_id = shmget (IPC_PRIVATE, getpagesize(),
IPC_CREAT | IPC_EXCL | S_IRUSR | S_IWUSR);
semaphore_id = binary_semaphore_allocation(IPC_PRIVATE, IPC_CREAT | IPC_EXCL | S_IRUSR | S_IWUSR);
binary_semaphore_initialize(semaphore_id);
shared_memory = (char*) shmat (segment_id, 0, 0);
sprintf (shared_memory, "%d", 100);
printf("%s\n", shared_memory);
child_pid = fork ();
if (child_pid != 0) {
for (i = 0; i < 1000000; ++i) {
binary_semaphore_wait(semaphore_id);
sprintf (shared_memory, "%d", atoi(shared_memory) + 1);
sprintf (shared_memory, "%d", atoi(shared_memory) - 1);
printf("%s\n", shared_memory);
binary_semaphore_post(semaphore_id);
}
}
else {
for (i = 0; i < 1000000; ++i) {
binary_semaphore_wait(semaphore_id);
sprintf (shared_memory, "%d", atoi(shared_memory) + 1);
sprintf (shared_memory, "%d", atoi(shared_memory) - 1);
printf("%s\n", shared_memory);
binary_semaphore_post(semaphore_id);
}
return 0;
}
printf("\nValor final: %s\n", shared_memory);
shmdt (shared_memory);
shmctl (segment_id, IPC_RMID, 0);
binary_semaphore_deallocate(semaphore_id);
return 0;
}
void sigint_handler(int signal_number)
{
int status=0;
system(CLEAR_SC);
printf(" -->Waiting for last clients to be attended\n");
while(wait(&status)!=-1); /*Waits until there is no more childs*/
/* Save changes in the database to the disk */
printf(" -->Terminating the server correctly\n");
printf(" -->Closing the database\n");
data_person * users = (data_person *) shmat(users_shared_memory,0,0);
int * newid = (int *) shmat(newid_shared_memory,0,0);
write_database(users,newid);
shmdt(users);
shmdt(newid);
/* Deallocate Shared Memory Segment */
shmctl(users_shared_memory, IPC_RMID, 0);
shmctl(newid_shared_memory, IPC_RMID, 0);
/* Deallocate Semaphore */
binary_semaphore_deallocate(semaphore);
/* Release the lock. */
lock.l_type = F_UNLCK;
fcntl (database, F_SETLKW, &lock);
close(database);
printf(" -->Have a nice day\n");
exit(status);
}
int main() {
char buf[BUF_SIZE];
int nread;
int flag = 0;
int nwrite;
int fdin,fdout;
int shmid;
const int shared_segment_size = BUF_SIZE + 1;
char* shared_memory;
key_t key = ftok("prog1.c", 1);
key_t keySem = ftok("tdf", 1);
key_t keySem1 = ftok("file", 1);
key_t keySem2 = ftok("rgv", 1);
int semid = binary_semaphore_allocation(keySem, 0666|IPC_CREAT);
printf("semid: %d\n ",semid);
int semid1 = binary_semaphore_allocation(keySem1, 0666|IPC_CREAT);
printf("semid1: %d\n ",semid1);
int semid2 = binary_semaphore_allocation(keySem2, 0666|IPC_CREAT);
printf("semid2: %d\n ",semid2);
binary_semaphore_initialize(semid);
binary_semaphore_initialize(semid1);
binary_semaphore_initialize_0(semid2);
shmid = shmget(key, shared_segment_size, 0666| IPC_CREAT);
if (shmid < 0)
printf("Shared memory get fail\n");
shared_memory = shmat(shmid, 0, 0);
shared_memory = "4555";
shared_memory[4] = '\0';
binary_semaphore_free(semid2);
sleep(10);
binary_semaphore_deallocate(semid);
binary_semaphore_deallocate(semid1);
binary_semaphore_deallocate(semid2);
return 0;
shared_memory[BUF_SIZE+1] = '0';
fdin = open("100mb_file", O_RDONLY);
//fdout = open("file.out", O_RDWR|O_CREAT,
//S_IRUSR|S_IWUSR);
int i = 0;
while ((nread = read(fdin, buf, BUF_SIZE)) > 0) {
printf("nread after while: %d\n", nread);
binary_semaphore_take(semid1);
printf("Take sem1\n");
binary_semaphore_take(semid);
printf("Take sem\n");
printf("iter: %d\n", i++);
if (nread < BUF_SIZE) {
buf[nread] = '\0';
//printf("buf last sem = %s \n", buf);
//shared_memory[BUF_SIZE+1] = '1';
}
//write(fdout, buf, BUF_SIZE);
printf("BUF_SIZE+1 = %c\n", shared_memory[BUF_SIZE +1]);
printf("read: %d\n", nread);
strcpy(shared_memory, buf);
//sleep(5);
binary_semaphore_free(semid);
printf("Free sem\n");
binary_semaphore_free(semid2);
printf("Free sem2\n");
//if (flag)
//shared_memory[0] = '\0';
}
sleep(2);
if (shmdt(shared_memory) == -1)
printf("shmdt fail\n");
else
printf("shmdt success\n");
if (shmctl(shmid, IPC_RMID, 0) == -1)
printf("shmctl fail\n");
else
printf("shmctl success\n");
binary_semaphore_deallocate(semid);
binary_semaphore_deallocate(semid1);
binary_semaphore_deallocate(semid2);
close(fdin);
//close(fdout);
return 0;
}
